Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
1
SENSITIVITY OF ULTRASONOGRAPHY IN THE DETECTION OF CAUSES OF
OBSTRUCTIVE JAUNDICE IN ADULT PATIENTS IN OBAFEMI AWOLOWO
UNIVERSITY TEACHING HOSPITALS COMPLEX,
ILE-IFE.
BY
DR. Olufunke O. FADAHUNSI
(MBChB)
DEPARTMENT OF RADIOLOGY,
OBAFEMI AWOLOWO UNIVERSITY TEACHING HOSPITAL COMPLEX
(OAUTHC), ILE IFE
BEING
A DISSERTATION SUBMITTED TO THE NATIONAL POSTGRADUATE MEDICAL
COLLEGE OF NIGERIA IN PARTIAL FULFILMENT OF THE REQUIREMENTS
FOR THE AWARD OF FELLOWSHIP IN RADIOLOGY
(FMCR)
MAY 2013
2
ATTESTATION
I hereby testify that this work was undertaken by me at Obafemi Awolowo University
Teaching Hospitals Complex, Ile-Ife and is an original work that has not been previously
reported elsewhere.
………………………………………………………
DR. FADAHUNSI, OLUFUNKE OMONIKE
3
CERTIFICATION
We certify that this work was carried out under our supervision by Dr. Fadahunsi
Olufunke Omonike of the Department of Radiology of Obafemi Awolowo University Teaching
Hospital Complex, Ile – Ife.
…………………………………
PROF. V. A. ADETILOYE FMCR, FWACS
Department of Radiology
ObafemiAwolowo University Teaching Hospital Complex,
Ile Ife,
Osun State.
……………………………………………………………
DR. B.O IBITOYE
Department of Radiology
Obafemi Awolowo University Teaching Hospital Complex,
Ile Ife,
Osun State.
SUMMARY
4
Background: Ultrasound is the safest, least invasive and cheapest initial imaging modality for
evaluation of the jaundiced patient. There is therefore a need to assess its sensitivity and
specificity in identifying the underlying etiology in cases of obstructive jaundice.
Materials and Methods: The study population included 80 adult patients aged 16 years and
above presenting with clinical and biochemical features of obstructive jaundice referred for
ultrasonography in the Radiology Department of Obafemi Awolowo University Teaching
Hospitals Complex, Ile-Ife. The degree and level of ductal dilatation was assessed and the cause
of obstruction was sought for sonographically via the trans-abdominal route using a MINDRAY
DC- 6Real time Ultrasound machine. Other sonographic hepatobiliary changes were noted. The
ultrasonographic diagnosis was subsequently compared with the surgical and/or histological
diagnosis, using them as the gold-standard.
Results: The overall sensitivity of ultrasound in detecting the cause of obstructive jaundice is
76.6% while the specificity is 98%. A strong agreement was also observed between the definitive
diagnosis and the level of obstruction reported on ultrasound. Pancreatic carcinoma (28.0%) is
the commonest cause of obstructive jaundice in this environment while choledocholithiasis
(21.3%) is the commonest benign cause. The least common cause is hepatocellular carcinoma
(1.3%).
Conclusion: Ultrasonography is a reliable imaging modality in diagnosing obstructive jaundice.
The level of sensitivity obtained in this preliminary study is adequate to aid the early resolution
of the cause of obstructive jaundice and could enhance the institution of early surgical
intervention in these patients thereby preventing the morbidities and mortalities that may attend
late interventions in them.
INTRODUCTION
5
Jaundice is the yellowish staining of the skin and sclera caused by high levels of bilirubin
in the blood.1It poses diagnostic and therapeutic challenges to the attending physician and
contributes significantly to high morbidity and mortality.2 Jaundice can be classified in two
ways: either as surgical and medical or obstructive and non obstructive.3,4 Medical or non
obstructive jaundice is caused by parenchymal disease of the liver or hemolytic anemia while
surgical or obstructive jaundice is jaundice resulting from obstruction to the flow of bile from the
liver to the duodenum. Surgical jaundice in particular is defined as ductal pathology potentially
correctible by surgery regardless of whether the biliary system is dilated or not. Obstructive
jaundice may also be due to disease of the pancreas.4, 5
Patients with non obstructive jaundice may not require further imaging studies as
percutaneous needle liver biopsy is often performed for further evaluation.6 This is not the case
with obstructive jaundice where early investigation to elucidate the precise etiology is of great
importance so as to minimize progression of the disease and accompanying complications if
obstruction is not relieved. Even though the cause can often be diagnosed clinically in some
cases, radiological investigations are required for confirmation of diagnosis in some of the
cases.7
Vast arrays of invasive and non invasive tests are available to diagnose and establish the
etiology of surgical jaundice. These range from trans-abdominal ultrasound, to computerized
tomography, percutaneous trans-hepatic cholangiography, endoscopic retrograde
cholangiopancreatography, magnetic resonance cholangiopancreatography and radionuclide
imaging. These examinations are effective to varying degrees in assessing both the cause and the
site of obstruction. However, ultrasonography remains the least invasive initial imaging modality
for the evaluation of jaundiced patients.6
6
Sonography has many other advantages including safety, non invasiveness, broad
availability, no use of radiation and low cost. This advantage becomes very important in
developing countries like Nigeria where most of the other investigations are rarely available and
when available, it is unaffordable by majority of the patients who live below the poverty line. On
ultrasound, the demonstration of biliary ductal dilatation, gallstones, hepatic mass lesions, or an
enlarged or abnormally shaped pancreas can be used to make appropriate diagnoses. Ultrasound
may also be employed in therapeutic interventions such as guided biopsy or drainage of cysts or
abscesses in the liver or pancreas.
However, sonography may be technically unsatisfactory in up to 40% of cases, primarily
due to obesity or accumulation of bowel gas, which prevents transmission of sound waves.8 It is
frequently more successful in identifying ductal dilatation rather than the cause. It may also miss
early cases of obstruction in which the biliary tree has not had sufficient opportunity to dilate. In
addition, the procedure may be difficult to perform in the postoperative patient with surgical
wounds, dressings, and drains that prevent close apposition of the sonographic probe to the
abdominal wall. Above all, it is highly operator dependent.8
Despite these, ultrasonography of the abdomen in the jaundiced patient is one of the
commonly ordered investigations by clinicians to differentiate medical from surgical jaundice
and to assess the level and cause of obstruction. In addition, other abdominal organs can be
assessed for complications.
The purpose of this study is to evaluate the efficacy of ultrasound in detecting the
causes of obstructive jaundice in our environment in order to have a local reference value of its
sensitivity and specificity. The study also attempts to determine the degree of success obtainable
in locating the level of obstruction using ultrasound. This will go a long way in helping clinicians
7
make a prompt diagnosis and instituting effective management. It will also minimize the number
of patients who will undergo invasive procedures and unnecessary ionizing radiation.
AIMS AND OBJECTIVES
BROAD:
8
To determine the sensitivity and specificity of abdominal ultrasonography, as a single
diagnostic tool in the detection of the causes of obstructive jaundice
SPECIFIC:
(1) To assess the degree of dilatation of the biliary tree and the level of the obstruction.
(2) To describe the hepatobiliary changes on ultrasound in obstructive jaundice.
(3) To compare the ultrasound diagnosis with a gold standard i.e. histology or surgical
findings as appropriate.
HYPOTHESIS:
Ultrasound is sensitive in detecting the cause and the levels of biliary obstruction in
patients with surgical jaundice.
9
JUSTIFICATION FOR THE STUDY
Obstructive jaundice is a common problem in surgical gastroenterological practice. It is
among the most challenging conditions managed by general surgeons and contributes
significantly to high morbidity and mortality.2 Studies have shown that early diagnosis and
treatment play an important role in the prognosis of patients with obstructive jaundice9, 10 and
early radiological diagnosis is usually made by ultrasound, computerized tomography, magnetic
resonance imaging, percutaneous trans-hepatic cholangiography and endoscopic retrograde
cholangiopancreatography.
However, other imaging modalities are not readily available in developing countries like
Nigeria where ultrasonography has remained the single most common diagnostic imaging
modality available.10-13 Where these imaging modalities are available, they are expensive and un
affordable for most of the patients, thus limiting their use as a first line modality of investigation
and management. . Therefore, the use of ultrasound for diagnosis of obstructive jaundice is of
great importance in our setting to determine the cause as well as the level of obstruction in these
patients. Determination of the sensitivity and specificity of ultrasound in detecting the cause of
obstructive jaundice will aid decision making by clinicians in adopting ultrasound for
investigation of these patients.
More importantly, in developed countries where all the advanced diagnostic facilities are
available and affordable, ultrasound is still recommended as the most appropriate initial imaging
modality in most of the cases by regulatory bodies.6 This recommendation is based on different
international studies which have shown that ultrasonography has achieved an accuracy rate of
80-97% in distinguishing obstructive from non obstructive jaundice with a reported accuracy of
50-60% in detecting the cause 12,14 although none of these studies was conducted in Africa.
10
With paucity of literature in this environment on the subject of the sensitivity of
ultrasound in investigating obstructive jaundice, there is no local reference value set yet for this
investigative modality in this environment. This study will therefore fill this void by providing a
local reference value for the sensitivity of ultrasound in detecting the cause of obstructive
jaundice. This may stimulate further research on this subject to validate findings and
recommendations of this study in other centers in our environment.
11
GROSS ANATOMY OF THE HEPATOBILIARY SYSTEM
An accurate knowledge of the anatomy of the liver and biliary tract, and their relationship
to associated blood vessels is essential for the performance of hepatobiliary sonography because
wide anatomic variations are common. The classic anatomic description of the biliary tract is
only present in 58% of the population.15
The liver, gallbladder, and biliary tree arise as a ventral bud (hepatic diverticulum) from
the most caudal part of the foregut early in the fourth week. This divides into two parts as it
grows between the layers of the ventral mesentery: the larger cranial part (pars hepatica) which is
the primordium of the liver, and the smaller caudal part (pars cystica) which expands to form the
gallbladder. Its stalk becomes the cystic duct. The initial connection between the hepatic
diverticulum and the foregut narrows, forming the bile duct. As a result of the positional changes
of the duodenum, the entrance of the bile duct is carried around to the dorsal aspect of the
duodenum.16
The biliary system can be broadly divided into two components, the intra-hepatic and the
extra-hepatic tracts. The secretory units of the liver (hepatocytes and biliary epithelial cells,
including the peri biliary glands), the bile canaliculi, bile ductules (canals of Hering), and the
intra hepatic bile ducts make up the intra-hepatic tract while the extra-hepatic bile ducts (right
and left), the common hepatic duct, the cystic duct, the common bile duct and the gallbladder
constitute the extra-hepatic component of the biliary tree.17,18 The cystic and common hepatic
ducts join to form the common bile duct some distance from the porta hepatis.
The common bile duct is approximately 8 to 10 cm in length and 0.4 to 0.8 cm in
diameter. The common bile duct can be divided into three anatomic segments: supra duodenal,
retro duodenal, and intra pancreatic. The common bile duct then enters the medial wall of the
12
duodenum, courses tangentially through the sub mucosal layer for 1 to 2 cm, and terminates in
the major papilla in the second portion of the duodenum. The distal portion of the duct is
encircled by smooth muscle that forms the sphincter of Oddi. The common bile duct may enter
the duodenum directly (25%) or join the pancreatic duct (75%) to form a common channel,
termed the ampulla of Vater.
The biliary tract is supplied by a complex vasculature called the peri biliary vascular
plexus. Afferent vessels of this plexus derive from hepatic arterial branches; they drain into the
portal venous system or directly into hepatic sinusoids. (Figure 1)
13
FIGURE 1: Schematic diagram of the hepatobiliary system19
DUODENUM
AMPULLA OFVATER
CYSTIC DUCT
PANCREAS
COMMON BILE DUCT
GALL
BLADDER
LIVER
INTRAHEPATIC DUCT
14
SONOGRAPHIC ANATOMY OF THE HEPATOBILIARY SYSTEM
The liver parenchyma has a uniform, homogenously medium level echotexture. The
hepatic veins, hepatic arteries, portal veins and the intra hepatic biliary ducts are tubular and
anechoic. The hepatic veins course obliquely towards the inferior vena cava, predominantly in
the upper one third of the liver, and their walls have less echogenicity than the portal vein walls.
The portal veins are found more predominantly in the middle third of the liver and both the
hepatic and portal veins run nearly perpendicular to each other, with the portal vein running
posteriorly. The bile ducts have moderately echogenic walls with no intrinsic flow. The
intrahepatic bile ducts normally measure less than 2mm, or less than 40% caliber of the adjacent
portal venous branch.
The union of the right and left hepatic ducts can be seen in the region of the porta
hepatis. The upper limit of normal for the diameter of the hepatic ducts varies with age. It could
reach 3mm at age 20, up to 8mm in older patients and up to 10mm post cholecystectomy.20
The gall bladder can be visualized as a pear shaped organ between the liver and the right
kidney. It contains sonolucent fluid and has an echogenic wall less than 3mm in thickness. The
size of the gall bladder varies between the fed and the fasting states, but can be up to 10cm long
and 3cm wide. The union of the common hepatic and cystic duct to form the common bile duct is
also seen after a variable distance from the porta hepatis. The common bile duct can sometimes
be visualized throughout its course but part of it is often obscured by gas. (Figures 2 and 3).
15
FIGURE 2: Ultrasound of the hepatobiliary system (longitudinal section) demonstrating the
liver, gall bladder and vascular channels.
16
FIGURE 3: Ultrasound of the hepatobiliary system (oblique view) showing the liver, portal vein
and the common hepatic duct (CHD) at the level of porta hepatis.
17
LITERATURE REVIEW
Jaundice is a symptom complex, characterized by yellowish colouration of tissues and
body fluids due to increase in bile pigments. It can be classified as haemolytic, hepatic or
obstructive.21The haemolytic and hepatic types can also be classified as medical jaundice while
the obstructive type is classified as surgical jaundice.
Obstructive jaundice is jaundice resulting from obstruction to the flow of bile from the
liver to the duodenum. In adults, extrahepatic obstruction accounts for 40% of patients
presenting with jaundice as the primary symptom and the incidence increases with advancing
age.6
The most common causes of obstructive jaundice are choledocholithiasis, neoplasm of
the pancreas, gallbladder, biliary tract or ampulla of Vater and pancreatitis. Other less common
causes include metastatic tumors to the biliary epithelium, hepatic tumor adjacent to the hilum,
perihepatic lymphadenopathy, sclerosing cholangitis and other forms of cholangitis.
Obstructive jaundice is commoner among females and the cause is mostly malignant
which carries a very poor prognosis, with a 2 year mortality rate of 95%.22,23
Choledocholithiasis is the commonest benign cause of obstructive jaundice while carcinoma of
the head of pancreas is the commonest malignant cause.22,24 However, a male preponderance has
been reported in some studies.25,26
Shama et al27 in their study found gallbladder carcinoma to be the commonest cause of
obstructive jaundice among North Indian patients, while studies carried out in Pakistan and
China noticed that cholangiocarcinoma is the commonest cause in that environment.28,29 This
shows environmental variations in the causes of obstructive jaundice, which was reported by
Mehdrad et al.30
18
Benign causes of jaundice were found among the younger age groups while malignant
causes were commoner in older patients.10,31 Siddique et al22 reported that most patients with
benign causes of jaundice were between 31 to 40 years while malignant causes were more
common in older patients and were maximally seen between 51 to 70 years of age.
Abdominal ultrasound is the initial imaging modality of choice in jaundiced patients
because it is non invasive, inexpensive and readily available although it is highly operator
dependent.32 It is used to differentiate obstructive from non-obstructive jaundice by evaluating
the internal transverse diameter of the common bile duct, and measurements above 8mm are
diagnostic of obstructive jaundice. In addition, the intra-hepatic ducts are also visible.32
Dewbury et al3 in their study found that ultrasound is able to accurately distinguish obstructive
from non obstructive causes in up to 97% of cases. The cause of the jaundice was diagnosed in
58% of patients. They reported that the basis of making the diagnosis is the identification of a
dilated biliary tree in the jaundiced patient. This was confirmed by other studies.12, 33, 34
Ultrasound is also observed to be well suited for visualizing the common hepatic ducts and the
proximal common bile duct.35
The sensitivity of ultrasound to correctly diagnose and establish the site of obstruction
was 94%, with a specificity of 96% according to Shama et al.27 Forty-four percent of their
patients were noticed to have a high obstruction while 56% had low obstruction. Obstruction at
the porta hepatis was due to gallbladder carcinoma in 91% of patients while carcinoma of the
pancreas was the cause of lower end block in 76%. Parenchyma liver disease or sclerosing
cholangitis may prevent biliary dilatation despite obstruction, thereby limiting the sensitivity of
ultrasound.32
19
One of the major limitations of ultrasound is the assessment of the distal common bile
duct and the pancreas which are often obscured by overlying bowel gas in about 30 to 50% of the
patients. Obesity is also an important limiting factor. It was noted that in sclerosing cholangitis,
the ducts may appear falsely normal while cholangiographic comparison reveals multiple
strictures and pruning with no dilatation.35
The level of obstruction can be divided into three categories viz hilar, suprapancreatic
and intrapancreatic. Hilar level of obstruction is obstruction at or above the porta hepatis
including the proximal part of the common hepatic duct. Supra-pancreatic level is defined as
obstruction from the lower limit of hilar level to the upper border of the head of pancreas while
intra-pancreatic obstruction is that involving the pancreatic and ampullary region of common bile
duct.36
In pancreatic masses, B mode ultrasound allows the detection of focal lesions, even small
ones about 10mm in diameter.37They are usually hypoechic or cystic. When an isoechoic mass is
identified, attention should be given to the size and nodularity of the contour of the pancreas.21
Contrast enhanced ultrasound can provide dynamic information concerning macro and micro
circulation of focal lesions and of normal parenchyma, thereby characterizing the lesion.38
D’Onofrio39 demonstrated a sensitivity of 88%, specificity of 97%, positive predictive values of
97.1% and accuracy of 96% in delineation of pancreatic masses by contrast enhanced ultrasound
(CEUS). It can also distinguish between adenocarcinomas, islet cell tumor and serous
microcystic adenoma by detecting their vascularization.37
Early diagnosis of gallbladder tumor is scarcely possible on the basis of symptoms. As
far as gallbladder cancer is concerned, it is already advanced by the time its diagnosis is made on
the basis of abdominal pain and presence of jaundice.27Three major patterns of gallbladder
20
masses have been described on sonography. In type 1, the gallbladder is surrounded or replaced
by a hypoechoic or heterogenous mass. In type 2, there is a focal or diffuse, irregular and
asymmetric wall thickening. In type 3, which is less common, a polypoidal and fungating intra-
luminal mass, is seen. Gallstones are seen in majority of the patients.21 Biliary obstruction in the
form of dilated intra-hepatic and common bile ducts may be seen because of direct extension via
the hepatoduodenal ligament or compression by lymphadenopathy. Differential diagnosis on
ultrasound includes complicated cholecystitis and xanthogranulomatous cholecystitis.21
Depending on the tumor type, the sensitivity of ultrasonography in depicting
cholangiocarcinoma is variable. Robeldo et al40 reported that the detectability of bile duct
cancers varies from 21% to 90%, with distal ductal carcinoma having the lowest percentage. This
was also confirmed by other studies.41, 42
Recently, a more definitive role in demonstrating cholangiocarcinoma with ultrasound
has been defined.43 Dilatation of the intra-hepatic bile ducts is the most common abnormality in
patients with ductal cholangiocarcinoma.44 When dilatation of only the intra-hepatic bile ducts is
observed, obstruction of the hilar bile ducts should be suspected, but middle and lower common
bile duct obstruction is probably suspected when both intra-hepatic and extra-hepatic bile ducts
are dilated.45, 46
With intra-hepatic tumors, the mass can be predominantly a homogenous or
heterogeneous lesion. It is usually hyperechoic in 75% of cases and may be isoechoic in about
10%of cases. Fifteen percent are hypoechoic with irregular borders and satellite nodules.43
Wilbupolprasert and Dhiensri47 observed that peripheral tumors are hypoechoic when they are
smaller than 3cm, but hyperechoic when larger.
With extrahepatic tumors, nearly 100% of cases of cholangiocarcinoma with polypoidal
intraluminal tumors are depicted at ultrasound, whereas ultrasound demonstrates the primary
21
sign of the mass in only 13% of cases involving sclerosing tumors and in only 29% of those with
exophytic masses43. A tumor that arises at the convergence of the right and left ducts are known
as hilar cholangiocarcinoma (Klatskin tumor) and account for approximately 10% to 26% of all
cholangiocarcinoma.48They classically manifest as segmental dilatation and non union of the
right and left ducts at the porta hepatis.49
In capable hands, modern high resolution color Doppler ultrasound is highly sensitive in
depicting, characterizing, and determining the resectability of a cholangiocarcinoma44. In more
than 90% of cases, ultrasound is sufficient for adequate imaging and staging. Diffuse tumors may
be difficult to demonstrate on ultrasound. Benign tumors of the bile duct and cholangitis may
simulate cholangiocarcinomas. Strictures caused by cholangitis may cause false-positive results
while sclerosing lesions may cause false- negative results43.
Choledocholithiasis is the presence of stones in bile ducts. The stones can form in the
gallbladder or in the ducts themselves. These stones cause biliary colic, biliary obstruction,
gallstone pancreatitis or cholangitis (bile duct infection and inflammation). Cholangitis, in turn,
can lead to strictures, stasis and choledocholithiasis.50
Ultrasonography may show echogenic structures casting posterior acoustic shadows in
the gallbladder and occasionally in the common bile ducts (this is less accurate because the
stones in the ducts most often do not cast posterior acoustic shadows).51 The common bile duct is
dilated and if not dilated early in the presentation, stones have probably passed.
Foreign bodies in the biliary tracts are rare causes of biliary obstruction. With recent
advancements in endoscopic and laparoscopic surgery, an increasing number of impacted foreign
bodies like endoclips and impacted surgical gauze in the common bile duct causing obstructive
jaundice have been reported.52, 53
Mirizzi syndrome is also a rare form of benign obstructive jaundice that is caused by a
stone impacted either in the gallbladder neck or in the cystic duct and impinging on the right side
22
of the common hepatic duct. This entity is often difficult to distinguish from cancers. 6% - 28%
of patients with a pre operative diagnosis of Mirizzi syndrome turn out to have a cancerous
stenosis.54
Ascariasis lumbricoides is the largest intestinal roundworm and its commonest extra
intestinal manifestation in the biliary system. Several studies have found trans-abdominal
ultrasound a reliable modality for the diagnosis and post therapeutic surveillance of biliary
ascariasis.55, 56 Common findings have been described by Khurro et al.57 Linear or curvilinear,
thick, echogenic, non shadowing structures, with central anechoic longitudinal tubes are typical
of ascariasis.
The inner tube or the double tube sign implies the visualization of the hypoechoic
alimentary canal of the worm. The worms are often seen as one or more non shadowing, tube-
like echoic structures, which may be straight or coiled (Strip sign). Overlapping coils or
aggregates of worms may have an appearance like spaghetti. Dilatation of the common bile duct
with or without a distended gallbladder is the next most common finding.57
23
MATERIALS AND METHODS
This prospective study was carried out in the Radiology department of Obafemi
Awolowo University Teaching Complex, Ile-Ife over a period of eleven months (August 2011
and June 2012.)
PATIENT SELECTION:
A total of 80 consecutive adult patients aged 16years and above referred to the
department for abdominal ultrasound with clinical and biochemical features of obstructive
jaundice were recruited into this study.
SAMPLE SIZE:
The samples size for this study was determined using the formula
N= Z2 Pq/d2. (Fishers formula)
N= desired minimum sample size
Z = standard normal deviation usually set at 1.96 corresponding to 95%
P = prevalence which is 5% =0.05
q = 1 - p = 1.0 – 0.05 = 0.95
d = degree of accuracy desired set at 0.05.
N= (1.96)2 x0.05 x0.95/ (0.05)2
N= 73
Allowing for attrition, sample size was 80 patients.
24
INCLUSION CRITERIA
All adult patients presenting with obstructive jaundice at OAUTHC Ile Ife with a serum
bilirubin level above 2mg/dl and serum alkaline phosphatase above 105micro mol/l.
EXCLUSION CRITERIA
All patients below the age of 16 years.
All patients with medical jaundice.
All patients who had neither surgical intervention nor pathological investigation.
25
METHODOLOGY
Adult patients aged 16 years and above, referred to the Radiology Department of
OAUTHC, Ile-Ife, on account of clinical and biochemical features of obstructive jaundice were
sonographically evaluated with MINDRAY Real time Ultrasound scanner model DC-6 with
Doppler facilities, curvilinear transducer probe with frequency range of 2.5 to 5.0MHZ after
obtaining informed consent from them (Appendix1). Results of initial biochemical assays
including the serum conjugated and unconjugated bilirubin levels as well as serum alkaline
phosphatase level were documented (Appendix 2).
Patients were examined in an overnight fasting state with the stomach distended with
water and the transducer output and receiver gain settings were optimized for each patient. With
the patient in a supine position, coupling gel was applied to the exposed abdomen in the right
upper quadrant. Scanning was done in both longitudinal and transverse planes, starting from the
midline to the lateral abdomen, and from the right upper quadrant to the pelvis. This
demonstrated the liver, the bowel loops and the retroperitoneal organs respectively (Fig 4 and 5).
With the patient in a left posterior oblique or left lateral decubitus position, the
intrahepatic and extrahepatic ductal systems were examined. This position causes the liver to
rotate anteromedially and be used as an acoustic window. The common bile duct was imaged by
placing the transducer below the right costal margin in the region of the mid-clavicular line with
the patient in an oblique position. The common bile duct was then followed into the
retropancreatic portion of the papilla when visualized.
26
FIGURE 4: Longitudinal sonogram of the hepatobiliary system with the patient in a
supine position demonstrating the liver parenchyma and the vascular channels.
Vascular
channels
Liver
27
FIGURE 5: Transverse sonogram of the hepatobiliary system with the patient in a
supine position showing the pancreas, superior mesenteric vein, portal vein and the
abdominal aorta.
Pancreas
Superior
mesenteric
vein Portal vein
Abdominal
aorta
28
The duct was imaged along its entire length and its diameter was measured at the level of the
porta hepatis, close to the liver and distally near the head of the pancreas when visualized. It was
evaluated for size, thickness of its wall and contents. Color flow and spectral analysis was also
used to differentiate the biliary ducts from vascular channels. (Fig. 6)
A diagnosis of obstructive jaundice was made when peripheral intra-hepatic radicles were
obvious, and these intra-hepatic radicles were distinguished from portal venous structures by
their irregular walls, position anterior to the portal vein, echo enhancement, peripheral location
and absence of color flow and spectral analysis. The common bile duct was considered dilated if
the diameter was 8mm and above in patients without previous biliary surgery and 10mm in
patients with previous biliary surgery.20
The liver hilum and the gall bladder were also scanned with the patient in the left lateral
decubitus position. The transducer was placed in the mid clavicular line and its position adjusted
until the gall bladder was located. The patient was asked to take a suspended full inspiration to
cause the gall bladder to descend below the lower costal margin. The transducer was then rotated
over the gallbladder until its true long axis section was achieved (Fig 7).
Movement of the patient is essential where there was sludge or stone(s) to demonstrate
movement. Color flow differentiated tumefactive sludge from a gallbladder mass. Erect imaging
was done to assess whether gallstones were mobile. The gallbladder wall thickness was regarded
as normal if it was less than 3mm. The anterior wall of the gallbladder was measured. Other
abdominal organs were scanned to exclude any pathology. Ascites is easily recognised when
present.
29
FIGURE 6: Longitudinal sonogram of the hepatobiliary system delineating the common hepatic
duct from portal vein with color flow in the portal vein.
Common
hepatic duct
Portal vein
Inferior vena
cava
30
FIGURE 7: Ultrasound of the hepatobiliary system in the left posterior oblique view
demonstrating the gallbladder, the common hepatic duct and the portal vein.
Gall bladder
Common
hepatic duct
Portal vein
31
Ultrasonographic liver span of 15.9cm in the right mid clavicular line was used as the cutoff
value58. Ultrasonographic diagnosis of the cause of biliary tree obstruction was made based on
the presence and location of mass lesion(s) or stone(s). No mass lesion or stone was found in 19
patients. In these patients, the cause of obstructive jaundice was inferred from the level of the
obstruction and other sonographic features. All these findings were documented (Appendix 2)
and compared with surgical and pathological findings. All the patients were followed up as
appropriate. Five of the patients died prior to surgery and only had post mortem histological
diagnosis.
DATA ANALYSIS
The biodata of the patients as well as the findings and measurements on sonographic
evaluation were entered into a computer spread sheet. Statistical analysis was performed using
Statistical Package for Social Sciences (SPSS) for windows (SPSS INC USA) version 16.0.
Appropriate descriptive and inferential statistical methods were applied and the results were
displayed by means of tables and figures as appropriate. The degree of agreement not due to
chance between sonographically detected level of obstruction and the definitve diagnosis was
assessed. The sensitivity and specificity of ultrasonography in determining the aetiology of
obstructive jaundice was calculated by comparing the ultrasonographic diagnosis with the
surgical and histopathological diagnosis (which is the gold standard).
32
ETHICAL CONSIDERATION
Approval for the study was obtained from the Research and Ethics Committee of the
Obafemi Awolowo University Teaching Hospital Complex Ile Ife, Osun State (Appendix 3).
33
RESULTS
In this prospective study, 80 cases of obstructive jaundice were investigated. The ages of
the patients ranged from 16 to 82 years, with a mean of 51.06 ± 14.95 years. The peak age group
was sixth decade with 23 (28.8%) patients. There were 28 (35%) males and 52 (65%) females,
giving a male to female ratio of 1:1.9 (Table1).
The mean age and standard deviations of patients with pancreatic cancer and
choledocholithiasis were 53.7±12.6 and 45.5±16.6 years respectively (Table 2).
Pancreatic carcinoma, gallbladder carcinoma and choledocholithiasis are more common in
females than males. All the patients with cholangitis were males while periampullary carcinoma
was seen only in females.
Pancreatic carcinoma was the leading cause of obstructive jaundice, accounting for 23
(28.8%) cases while choledocholithiasis accounted for 17 (21.3%) cases. Other common causes
included gall bladder carcinoma 15(18.8%), periampullary carcinoma 6(7.5%),
cholangiocarcinoma 4(5.0%), metastatic lesions 5(6.3%), liver cirrhosis 4(5.0%), cholangitis
2(2.5%), primary liver cell carcinoma 1(1.3%), advanced gastric carcinoma 2(2.5%) and
lymphoproliferative disease 1(1.3%) (Fig 8). The ultrasound scan diagnoses of the studied
patients were also presented in table 3.
The total serum bilirubin (TSB) levels ranged from 12mg/dL to 694 mg/dL with a mean
of 213.8 ± 165.4 mg/d. All the patients had predominantly conjugated hyperbilirubinaemia, with
serum conjugated bilirubin levels ranging from 8 to 674 mg/dL (mean=182.4 mg/dL ± 149.9
mg/dL). Similarly, the serum alkaline phosphatase of the studied patients ranged from 111 IU/L
to 2,805 IU/L with a mean of 576 IU/L ± 576 IU/L (Table 4).
34
Table 1: Age and gender distribution at presentation
Age (years)
Gender
Frequency (%)
Male Female Total
16-19 2(2.50) 1(1.25) 3(3.75)
20-29 2 (2.50) 5 (6.25) 7 (8.75)
30-39 1 (1.25) 6 (7.50) 7 (8.75)
40-49 4 (5.00) 8 (10.00) 12(15.00)
50-59 8 (10.00) 15 (18.75) 23(28.75)
60-69 11 (13.75) 11 (13.75) 22(27.50)
70-79 0 (0.00) 4 (5.00) 4 (5.00)
80-89 0 (0.00) 2 (2.50) 2 (2.50)
Total 28(35) 52(65) 80(100)
35
TABLE 2: Mean age and sex distribution by definitive diagnosis.
Definitive Diagnosis Age
(Mean±SD)
M: F
Pancreatic carcinoma
53.7±12.6 1:3.6
Choledocholithiasis 45.5±16.6 1:3.3
Liver cirrhosis 43.0±31.2 1:1
Hepatocellular carcinoma 23.0±0.0 All males
Advanced Gastric carcinoma 42.0±11.3 1:1
Gall bladder carcinoma 53.1±8.0 1:2
Cholangitis 52.5±10.6 All males
Cholangiocarcinoma 67.8±8.3 4:1
Periampullary carcinoma 56.2±18.6 All females
Lymphoproliferative disease 43.0±0.0 All males
Metastatic disease 43.6±6.7 1.5:1
M: F=Male/Female Ratio.
36
FIGURE 8: Etiological spectrum of obstructive jaundice based on intra-operative diagnosis.
29%
21%
5%
1% 3% 19% 3%
5%
7%
1%
6%
INTRAOPERATIVE DIAGNOSIS
Pancreatic carcinoma
Choledocolitiasis
Liver Cirrhosis
PLCC
Advanced Gastric Carcinoma
Gall bladder Carcinoma
Cholangitis
Cholangiocarcinoma
Periampullary Carcinoma
Lymphoproliferative disease
MetastaticDisease
37
TABLE 3: Etiological spectrum of obstructive jaundice based on ultrasound diagnosis
Ultrasound Diagnosis Frequency Percent (%)
Pancreatic carcinoma 23.0 28.8
Choledocholithiasis 15.0 18.7
Gallbladder Carcinoma 13.0 16.3
Periampullary Carcinoma 8.0 10.0
Cholangiocarcinoma 4.0 5.0
Metastatic Lesion 4.0 5.0
Choledocholithiasis with Liver
Cirrhosis 3.0 3.7
Cholelithiasis 3.0 3.8
Cholecystitis 2.0 2.5
Lymphoproliferative Disease 2.0 2.5
Gastric Carcinoma 1.0 1.2
Hepatocellular Carcinoma 1.0 1.3
Liver Cirrhosis 1.0 1.2
Total 80 100
38
Table 4: Serum Bilirubin and Alkaline Phosphatase Levels at Onset of Presentation.
Mean ± SD
Median
Range
Total Bilirubin (mg/dL)
213.8±165.4
162.0
12.00-694.0
Conjugated Bilirubin (mg/dL)
182.4±149.9
140.0
8.00-674.0
Alkaline Phosphatase (IU/L)
576.0±576.0
280.0
111.00-2805.0
SD= Standard deviation
39
Hepatobiliary ultrasonography revealed dilatation of the intrahepatic ducts in 75 (93.7%)
of the patients. Forty patients had dilatation of the extrabiliary tree up to the distal common bile
duct, while dilatations up to the proximal common bile ducts were seen in 20 (25%) patients.
Common hepatic ductal dilatation accounted for 18.8% (15 patients). Only five (6.3%) of the
patients had no significant ductal dilatation on ultrasound scan. (Table 5, Fig 9 and 10)
The measured common bile duct diameters ranged between 3.0mm and 32.0mm, with a
mean of 13.7±7.3mm, while the common hepatic duct diameters ranged from 4.5mm to 28.0mm,
with a mean of 12.8±4.8mm. When visualized, the pancreatic duct diameter ranged between
2.9mm and 13.0mm with a mean of 5.1±2.6mm. (Table 6)
A strong agreement was also observed between the definitive diagnosis and the level of
obstruction reported on ultrasound. All the 23 cases of pancreatic head carcinoma had shown
distal common bile duct dilatation on ultrasound scan, while 14 out of the 15 (93%) cases of gall
bladder carcinoma had common hepatic duct and/or proximal common bile duct obstruction.
Periampullary carcinoma also had distal common bile duct dilatation in all the six cases as
shown in Table 7.
40
Table 5: Prevalence of biliary tree dilatation
Biliary Duct
Number of patients
Percent (%)
Distal CBD
40.0
50.0
Proximal CBD
20.0
25.0
CHD
15.0
18.7
None
5.0
6.3
Total
80.0
100.0
CHD: Common Hepatic Duct.
CBD: Common Bile Duct.
41
FIGURE 9: Ultrasound of the hepatobiliary system (oblique section) showing dilated intra-
hepatic ducts and common hepatic ducts. The portal vein is seen in its posterior aspect.
Dilated
common
hepatic duct Portal vein
42
FIGURE 10: Ultrasound of the hepatobiliary system (oblique view) demonstrating dilated
common bile duct measuring 20.4mm.
Distal
common
bile duct Portal
vein
43
Table 6: The biliary ducts diameter at presentation
Mean ± SD
Median
Range
Common bile Duct (mm)
13.7±7.3
13.9
3.0-32.0
Common hepatic Duct (mm)
12.8±4.8
12.0
4.5-28.0
Pancreatic Duct (mm)
5.1±2.6
4.5
2.9-13.0
= Standard deviation
44
TABLE 7: Comparison of the level of ductal obstruction on ultrasound with intra operative
diagnosis
Intra operative diagnosis Common
hepatic duct
obstruction
Proximal common
bile duct
obstruction
Distal common
bile duct
obstruction
No ductal
dilatation
Pancreatic carcinoma 0 0 23 0
Choledocholithiasis 3 9 2 3
Gallbladder carcinoma 5 9 1 0
Periampullary carcinoma 0 0 6 0
Metastatic lesion 3 0 2 0
Cholangiocarcinoma 2 1 1 0
Liver cirrhosis 2 0 2 0
Cholangitis 0 0 0 2
Gastric carcinoma 0 0 2 0
Hepatocellular carcinoma 0 1 0 0
Lymphoproliferative
disease
0 0 1 0
45
However, no definite lesion was visualized in 19 (23%) patients and the diagnosis of
the cause of obstruction in these cases was inferred based on the level of obstruction and other
sonographic features. The ultrasound diagnoses in this group of patients include periampullary
carcinoma, pancreatic carcinoma, cholangiocarcinoma and cholecystitis.
Stones were visualized in the CHD or CBD in all the patients (100%) diagnosed as
having Choledocholithiasis (Fig13). A mass lesion was seen within the lumen of the gallbladder
in 7(53.8%) of the patients with gallbladder carcinoma (Fig.14) while heterogenous mass was
demonstrated in the gallbladder fossa in 3(23%) patients (Fig 15). Asymmetric thickening with
irregular gall bladder wall was noted in 1(7.7%) of the patients. The gall bladder structure was
not demonstrable in 2(15.3%) of the patients diagnosed with gall bladder carcinoma; instead,
stones were seen in the region of the gallbladder.
Twenty-three (28.8%) patients had ultrasonic diagnosis of pancreatic carcinoma. The
diagnosis was based on the presence of mass lesions in 20 (87%) of them (Fig 16), while the
pancreatic echotexture in the other 3 (13%) patients was heterogenous, with irregular margins.
Two (50%) of the four patients diagnosed with cholangiocarcinoma had dilatation of the
intrahepatic ducts up to the level of the porta hepatis with abrupt tapering and non visualization
of the extrahepatic ducts. No mass lesion was seen. This was diagnosed as hilar
cholangiocarcinoma (Fig17). The other 2 (50%) patients had hypoechoic masses within the
lumen of the CBD and CHD respectively. Other findings are well represented in Figures18, 19
and 20.
46
FIGURE 13: Longitudinal sonogram of the hepatobiliary system showing a rounded
calcific structure with posterior acoustic shadowing within the lumen of the proximal
common bile duct in choledocholithiasis.
calcific
stone in the
common
bile duct
47
FIGURE 14: Longitudinal sonogram of the hepatobiliary system demonstrating a hypoechoic
mass lesion in the gallbladder fundus with tumefactive sludge in its distal aspect. This is a case
of gallbladder carcinoma.
48
FIGURE 15: Longitudinal sonogram of the heptobilary system showing a gall bladder mass
with calcific structures casting posterior acoustic shadow within it in a case of gallbladder
carcinoma.
Gallbladder mass
with calcific stones
49
FIGURE 16: Transverse sonogram of the retroperitoneal region demonstrating an
enlarged pancreas with a lobulated, hypoechoic mass lesion in the head of the pancreas.
This is a case of pancreatic carcinoma.
Enlarged
pancreatic
tail
Hypoechoic
mass
50
FIGURE 17: Longitudinal sonogram of the hepatobiliary system showing intrahepatic
ductal dilatation up to the hilar region with no obvious mass lesion. A case of hilar
cholangiocarcinoma confirmed at surgery.
Dilated common
hepatic duct
51
FIGURE 18: Transverse sonogram of the hepatobiliary system showing grossly dilated
biliary ducts, gallbladder and pancreatic duct with no obvious mass lesion. This is a case
of periampullary carcinoma.
Pancreatic
ductal
dilatation
Dilated
distal
common
bile duct
Dilated
gallbladder
52
FIGURE 19: Longitudinal sonogram of the hepatobiliary system demonstrating thickened
gallbladder wall with normal biliary duct. A case of cholangitis misdiagnosed as cholecystitis.
53
FIGURE 20: Longitudinal sonogram of the hepatobilary system demonstrating multiple
hypoechoic masses with moderate color flow on Doppler interrogation. This is a case of
hepatocellular carcinoma.
.
Hypoechoic mass
with color flow
Dilated
intrahepatic duct
54
The preoperative ultrasonographic diagnosis was subsequently compared with the
definitive diagnosis and the sensitivity, specificity, positive and negative predictive values of
ultrasonography was based on this comparison (Table 10). The overall sensitivity of ultrasound
in detecting the etiology of obstructive jaundice was 76.6% while the specificity was 98%.
.
55
Table 8: Comparison of ultrasound diagnosis with definitive diagnosis
Ultrasound Diagnosis Accuracy
(%)
PPV
(%)
NPV
(%)
Sensitivity
(%)
Specificity
(%)
Pancreatic carcinoma 90.9 85.0 92.0 81.0 94.6
Choledocholithiasis 88.8 75.0 92.0 70.7 93.7
Liver cirrhosis 94.9 50.0 97.0 50.0 97.0
Hepatocellular carcinoma 100.0 100.0 100.0 100.0 100.0
Gastric carcinoma 98.8 100.0 98.7 50.0 100.0
Gall bladder carcinoma 94.0 92.0 95.0 80.0 98.0
Cholangitis 97.5 0.0 97.5 0.0 100.0
Cholangiocarcinoma 100.0 100.0 100.0 100.0 100.0
Periampullary carcinoma 96.3 62.5 100.0 100.0 96.0
Lymphoproliferative disease 98.8 50.0 100.0 100.0 99.0
Metastatic disease 98.8 100.0 99.0 80.0 100.0
PPV: Positive Predictive Value; NPV: Negative Predictive Value.
56
DISCUSSION
In this study of the ultrasonographic evaluation of 80 patients with obstructive jaundice,
there were more females than males with a male to female ratio of 1:1.9 which is similar to
reports of many previous studies. 22, 23, 59It is however observed that a previous report25 from this
institution about 20 years back found a slightly higher male preponderance. It is unclear if the
change over time is due to a smaller sample size used in their study or a change in trend in the
demographic pattern and spectrum of biliary diseases in our environment.
Majority of patients in this study (71.2%) had malignant obstructive jaundice with
pancreatic carcinoma as the commonest cause. This is similar to the findings by Lawal et al25 and
Rahman et al24 in Nigeria. Bekele et al13 and Huis et al60 however reported benign conditions as
the most common causes of obstructive jaundice among their patients in Ethopia and Croatia
respectively. Choledocholithiasis was found to be the commonest benign cause in these areas.
The reason for the difference in the disease pattern causing obstructive jaundice may be related
to regional dietary and social factors.61 Al Am et al55 and Sur et al56 in their studies in Saudi
Arabia and Yemen respectively, reported Ascaris lumbricoides infestation to be frequently
associated with biliary tract obstruction. However, no such case was encountered in the course of
the present study. These observations reflect differences in the etiological pattern of obstructive
jaundice across different countries.
The commonest level of obstruction in the present study was at the intra pancreatic
common bile duct which was found in 40 (50%) of the patients, followed by the supra pancreatic
common bile duct in 20 (25%) patients. Fifteen (18.8%) patients had obstruction at the level of
the porta hepatis while there was no sonographic evidence of obstruction in 5 (6.3%) patients.
Similar findings were noted in the study carried out by Upadhyaya et al34 in India in which 27%
57
of their patient had obstruction at the level of the porta hepatis, 34% at the supra pancreatic level
and 38% had intra pancreatic duct level obstruction. However, Ghimre et al36 reported that their
patient from Nepal had hilar level obstruction in 38% of cases, supra pancreatic duct obstruction
in 33% of cases while 28% of their patients accounted for intra pancreatic level obstruction. The
difference in the etiology of obstruction may account for this variation in observation.
The non-dilatation of the biliary ducts in five patients in the present study probably
accounted for the ultrasound misdiagnosis of two cases of cholangitis and those of
choledocholithiasis which were wrongly diagnosed as cholecystitis and cholelithiasis
respectively. This was also noted by Samp et al4 who observed that 10% of their patients had
non-dilated biliary tree due to sclerosing cholangitis and were misdiagnosed as non obstructive
jaundice. These cases emphasize the point that in the absence of ductal dilatation on
ultrasonography, the presence of a clinical history of obstructive jaundice with biochemical
findings also pointing to an obstructive etiology should prompt further diagnostic investigation
using other imaging modalities.62
Intraoperative dissections in the hepatopancreatobiliary tree can be challenging for
surgeons and a preoperative diagnosis of the exact site of obstruction is always required to plan
surgical intervention. In this study, a strong agreement was observed between the definitive
diagnosis and the level of obstruction reported on ultrasound which is in agreement with various
other studies reported elsewhere36, 63. This makes preoperative ultrasound a valuable tool for the
surgeons in this environment.
The sensitivity and specificity of ultrasonography in diagnosing pancreatic carcinoma
in the index study was 80.95% and 94.6% respectively. This is quite remarkable when compared
with Admassie et al11 in which sensitivity and specificity of 50% and 90% respectively were
58
achieved. The higher sensitivity noted in the present study may be due to greater dilatation of the
common bile duct and hepatic duct noted in this study, the higher resolution of the modern
equipment and the technique of examining the patients in an anterior oblique position with the
stomach fully distended with water. Further studies with a larger number of subjects are however
suggested to confirm these findings. D’Onofrio39 et al demonstrated a sensitivity of 88%,
specificity of 97%, predictive values of 97.1% and accuracy of 96% as against sensitivity of
80.95%, specificity of 94.6%, predictive values of 85% and accuracy of 90.9% in this study. This
higher value is probably due to the fact that ultrasonographic contrast agent which is not
available in our environment was used by D’Onofrio et al39 in their study.
The ultrasound features of pancreatic carcinoma in patients undergoing diagnostic
ultrasound in this study included biliary duct dilatation up to the level of the distal common bile
duct, pancreatic duct dilatation, and mass lesion in the head of pancreas with irregularity of its
outline. The body of the pancreas was also seen to be bulky in some cases. Small mass lesions
were not visualized in some cases contrary to Recaldini et al37 who stated that the B mode
ultrasound allows detection of focal small lesions as small as 10mm in diameter. This may have
been due to higher resolution of the equipment used by Recaldini et al37 or the fact that most of
the small mass lesions encountered in the present study were isoechoic. The gall bladder in most
of the cases of pancreatic carcinoma was also grossly dilated and sludge filled. These
ultrasonographic features were also reported by Siddique et al22 in patients from Pakistan.
Gallbladder carcinoma was the next most common cause of malignant obstructive
jaundice in the index study. The three major sonographic features of gall bladder carcinoma
reported by Gohil et al21 were seen in this study and these are, a heterogeneous or hypoechoic
mass lesion replacing the gall bladder, a focal or diffusely irregular or asymmetrical wall
59
thickening and a polypoid and fungating intra luminal mass within the gall bladder. Over the
course of this study, another ultrasonographic feature which was not described by Gohil et al was
however observed and confirmed at surgery. This was non visualization of the gall bladder on
ultrasound, along with small rounded echogenic structures casting posterior acoustic shadows
distal to the region of the porta hepatis. This was initially misdiagnosed as chronic cholecystitis
with choledocholithiasis. The surgical finding in this case was that of an advanced infiltrating
gall bladder carcinoma, walled off by bowel loops. This sonographic feature had been
documented before in a report by Alatise et al64 in which patients with gallbladder carcinoma
were similarly misdiagnosed as having cholelithiasis and cholecystitis. Gohil et al21 had earlier
alluded to this possibility while noting cholelithiasis and cholecystitis as close differentials of
gallbladder carcinoma.
The common hepatic and proximal common bile ducts were dilated. Gall stones were
also seen in majority of the patients similar to the findings of Gohil et al.21 The sensitivity,
specificity and accuracy of ultrasound in diagnosing gall bladder carcinoma in this study was
80%, 90% and 94% respectively which is lower than the 100% reported by Upadhyaya et al.35
This may partly be due to the additional unrecognized sonographic feature of advanced gall
bladder carcinoma encountered in the index study. However, further studies are suggested to
confirm this observation.
Choledocholithiasis was the most common benign cause of obstructive jaundice and
accounted for 21.3% of the cases. The sensitivity, specificity accuracy of ultrasound was 70.7%
and 93.7%, 88.8% respectively. The accuracy of ultrasound is higher than that of Uphadyaya35
who recorded 63.1%. Improved resolution of the equipment used in the present study and
diagnostic effort to elicit the cause of jaundice may account for this relative difference. The
60
sonographic features in choledocholithiasis are dilated ducts with echogenic structures casting
posterior acoustic shadows within the lumen of the ducts. In this study, three patients presenting
with choledocholithiasis had normal biliary tree, perhaps because the ductal obstruction was still
early with no corresponding dilatation of the biliary ducts at that stage. These were misdiagnosed
as non-obstructive jaundice. This phenomenon was also reported in some of the patients
investigated by Upadhyaya et al.35
The sensitivity of ultrasound in diagnosing cholangiocarcinoma in the present study was
100% which was seen to be at variance with Robeldo et al40 that reported that the detectability of
bile duct cancer varies from 21-90% with the distal common bile duct having the lowest
percentage. Both the proximal and the distal bile duct cancers were encountered in this study and
the sensitivity and accuracy of ultrasonography was not lowered despite this. The higher
sensitivity encountered in this study may be due to the fact that all extra hepatic bile duct masses
seen in this study were polypoidal intra luminal tumors. This is in agreement with Anand et al43
who reported accuracy of 100% for polypoidal intra luminal tumors and 13% for cases involving
sclerosing tumors and 29% for exophytic tumors.
Sonographically, 50% of those that presented with cholangiocarcinoma in the present
study had no obvious mass lesions but dilated intrahepatic duct up to the hilar region and normal
extrahepatic duct diameter. This is in agreement with Saini et al65 who predicted a probability of
a malignant lesion when there is abrupt tapering of bile duct with no obvious lesion. Ahrendt et
al66 in their study found out that 60% to 70% of cholangiocarcinoma occur at the hilar region.
This percentage is higher than the 50% of hilar cholangiocarcinoma encountered in this present
study. However, Meyer et al48 stated that hilar cholangiocarcinoma accounts for only 10-26% of
61
all cholangiocarcinoma. The relative small number of cases seen in the index study may
however not be able to explain the incidence of hilar cholangiocarcinoma in this environment.
Periampullary carcinoma was a very close differential of pancreatic carcinoma in this
present study. Some of the cases of periampullary carcinoma were misdiagnosed as pancreatic
carcinoma and vice versa. Their anatomical close relationship with the inclusion of carcinoma of
the pancreatic head in the component of periampullary carcinoma67and the double duct
appearance with no obvious mass lesion seen on ultrasonography in both pancreatic carcinoma
and periampullary carcinoma may account for this.
Hepatocellular carcinoma and liver cirrhosis are primarily medical jaundice with
cholestatic complication due to tumor, lymph node or portal vein thrombosis. The sensitivity of
ultrasound in detecting the cause is always low especially if the mass lesion is very small.68 The
sensitivity of 100% seen in hepatocellular carcinoma in this present study may be due to the fact
that only one patient presented with the disease.
The etiology of obstructive jaundice in this study had to be inferred by indirect signs in
19 (23%) patients due to non visualization of a mass lesion or stone as the cause of obstruction.
This was associated with misdiagnosis and consequently lowered the sensitivity of ultrasound in
the study; thus further confirming the fact that ultrasound has limited value in visualizing small
pancreatic, gallbladder and periampullary mass lesions.69
The comparison of ultrasound findings in this study with surgical and histological results
showed positive ultrasound diagnostic markers in detecting the cause of obstructive jaundice
with overall sensitivity of 76.6% and specificity of 98%. This finding is similar to that of Leing
FC70 which although it’s a retrospective study, had shown the correct identification of the level
and cause of biliary obstruction by ultrasound in 91.8% and 70.9% of patients respectively.
Gibson et al,71 in their series had found that ultrasonography correctly identified the level of
62
obstruction in 95% of cases and the cause in 88%. Similarly Kumar et al72 in their own study
concluded that ultrasonography as a single radiological investigation is sufficient in the
evaluation of the majority of patients with obstructive jaundice with a sensitivity of 84% in
detecting its cause. The higher sensitivity encountered in the last two studies compared with the
present study is probably due to the cases in which diagnosis had to be inferred from indirect
signs in this study and the fact that some of these studies were conducted in dedicated
hepatopancreatobiliary referral units with high patient turnover and experience.
It is believed that adoption and persistent deployment of USS for diagnosis of obstructive
jaundice in our setting may improve the sensitivity obtained from this study. Dewbury et al3 in
their study however got a lower sensitivity in ultrasound detection of causes of obstructive
jaundice with a value of 58%. The higher sensitivity demonstrated in the present study might be
attributable to the modern high resolution ultrasound machine used, compared to the machines
available in the 20th century when Dewbury et al3 performed their study.
63
CONCLUSION
Ultrasonography is a safe non invasive, inexpensive, accessible, repeatable imaging
modality which identifies bile duct obstruction and readily demonstrates both benign and
malignant cause of obstructive jaundice in this environment. In this study, the overall sensitivity
and specificity are 76.6% and 98% respectively. This level of sensitivity is comparable to that
reported for more expensive and more invasive imaging modalities such as CT, MRI, PTC and
ERCP in some studies.28,73
We believe that the level of sensitivity obtained in this preliminary study is adequate to
aid the early resolution of the cause of obstructive jaundice and could enhance the institution of
early surgical intervention in these patients thereby preventing the morbidities and mortalities
that may attend late interventions in them. In our setting where other expensive imaging
modalities are usually beyond the reach of a large number of patients, adoption of ultrasound for
evaluation of obstructive jaundice as earlier recommended by the American Society of
Radiologist (ASR)5 would go a long way in enhancing surgical care of the jaundiced patients.
The poor outcome of treatment of obstructive jaundice may not necessarily be due to non
availability of advanced diagnostic imaging modalities but rather to late presentation and
advanced stage of the diseases at presentation.
64
RECOMMENDATION
Obstructive jaundice is among the challenging conditions managed by general surgeons
and contributes significantly to high morbidity and mortality. There is therefore the need for the
radiologist to be vigilant in sonographic evaluation of the hepatobiliary system in order to make
adequate and prompt diagnosis concerning the etiology of the obstruction. There is the need to
systematically evaluate the hepatobiliary system of all the patients presenting with clinical
features of jaundice in details and also asymptomatic elderly and middle aged patients in order to
recognize early pathological changes and pick the disease in an early stage.
In many dedicated hepatobiliary centers in developed economies, intraoperative
ultrasound is commonly performed by surgeons to aid diagnosis and ascertain level of
obstruction. In our setting where such facilities are not readily available to the surgeons,
perioperative ultrasound is therefore recommended to obtain a highly specific biliary anatomy
for the surgeons as demonstrated in this study.
Because of the low cost and high level of accuracy of ultrasound in detecting the
cause of obstructive jaundice, it would be recommended that it should be used as a screening tool
for patients with vague abdominal pains and suspected jaundice in order to detect the disease
state at a very early, possibly curable stage.
65
Appendix 1
INFORMED CONSENT TO PARTICIPATE IN RESEARCH
Investigator: Fadahunsi Olufunke Telephone No.: 0803-616-7101 or 0816-494-2505
E-mail: [email protected]
Institution: Obafemi Awolowo University, Ile-Ife. Department: Radiology
TITLE OF PROJECT: Sensitivity of Ultrasonography in the Detection of causes of Obstructive
Jaundice in Adult Patients in Obafemi Awolowo University Teaching Hospitals Complex Ile-Ife.
INTRODUCTION: On account of your clinical and biochemical features of obstructive jaundice, you
have been chosen as one of the respondents in this research study.
PURPOSE: This study is aimed at evaluating the efficacy of ultrasound in detecting the causes of
obstructive jaundice in our environment and this will go a long way in helping clinicians in decision
making for a prompt diagnosis and in instituting effective management for this condition.
PROCEDURES: You will be examined in an overnight fasting state using a real time ultrasound scanner
to scan your abdomen. The ultrasound findings will be written out for you to give your doctor who will
also keep us informed on the surgical findings after you have been operated upon.
BENEFITS: If you agree to take part in this study you will not pay for this investigation which you
would have paid for as part of service rendered for the management of your medical condition. You may
also benefit by gaining psychological reward involved in contributing to medical knowledge.
RISKS: There are no physical risks associated with the procedure.
CONFIDENTIALITY: All information gathered in this study will be kept confidential. When findings
of this study are reported in scientific journals or meetings, you will not be identified.
RESPONDENTS’ RIGHTS: You have a right to decline participation in the study. If you decline or
withdraw from the study, you shall suffer no disadvantages whatsoever for such action.
I agree to participate in this study: YES NO
Signature/thumbprint of Respondent____________________ Date_________________
Signature/thumbprint of Witness____________________ Date _________________
CONTACT ADDRESS OF RESPONDENT_________________________________________
CONTACT ADDRESS OF WITNESS_______________________________________________
66
Appendix 2
Patient’s Pro-forma for Data Collection
Patient’s Name: ………………………………………………………………………….
Hospital Number: …………………. Age: ………… Sex: male female
Total Serum Bilirubin Level: …………………………………………………………….
Conjugated Bilirubin Level: ………………………………………………………………
Serum Alkaline Phosphatase Level: ………………………………………………………
ULTRASOUND FINDINGS
Liver Span: ………………………………………………………………………………….
Intrahepatic duct Diameter: …………………………………………………………………
Common hepatic duct Diameter: ……………………………………………………………
Common bile duct Diameter: ……………………………………………………………….
Gall bladder wall Thickness: ………………………………………………………………..
Liver Echotexture: ………………………………………………………………………….
Location of Stone or Mass Lesion: ………………………………………………………….
………………………………………………………………………………………………..
Sonographic Appearance of the Gallbladder: ………………………………………………..
Sonographic Appearance of the Pancreas: ………………................................................
Ascites: ………………………………………………………………………………………..
Abnormal findings in other Abdominal Organs: …………………………………………….
Others: …………………………………………………………………………………………
………………………………………………………………………………………………….
67
68
REFERENCES
(1) Marks JW. Jaundice signs, symptoms and treatment. Medicine Net 1996-2011
Available at http://www.medicinenet.com/jaundice/page5.htm. (Accessed 1/4/2011).
(2) Ahmad I, Jan AU, Ahmad R. Obstructive Jaundice. J Postgrad Med Inst 2001,
15:194-198.
(3) Dewbury KC, Joseph AEA, Hayes S, Murray C. Ultrasound in the Evaluation and
Diagnosis of Jaundice. Brit J of Radiol 1979;52:276-280.
(4) Samp WF, Sarti DA, Goldstein LI, Weiner M, Kadell BM. Gray Scale
Ultrasonography of the jaundiced patient. Radiol 1978;128:719-725.
(5) Menzel J, Poremba C, Dieti K-H, Domschke W. Preoperative Diagnosis of bile duct
stricture, comparison of intraductal Ultrasonography with conventional
Endosonography. Scand J Gastroenterol 2000;35:77-82.
(6) Foley WD, Bree RL, Rosen MP, Gay SB, Grant TH, Heiken JP, et al. Expert Panel
on Gastrointestinal Imaging. ACR Appropriateness Criteria® jaundice. Reston
(VA): American College of Radiology (ACR); 2008.
(7) Chen TH, Davis MA, Seltzer SE, Jones B, Americo AA, Finberg HJ, et al.
Evaluation of Hepatobiliary imaging by Radionuclide Scintigraphy,
Ultrasonography and contrast Cholangiography. Radiol 1979;133:761-767.
(8) Stillman AE. Jaundice. NCBI Bookshelf 2011;87:448-456.
(9) Han XC, Li J-L, Han G. Surgical Mortality in Patients with Malignant Obstructive
Jaundice: a multivariate discriminant analysis. HBPD Int 2003;2:435-440.
(10) Chalya PL, Kanumba ES, Mchembe M. Etiological Spectrum and Treatment
Outcome of Obstructive Jaundice at a University Teaching Hospital in North
69
Western Tanzania: A diagnostic and therapeutic challenges. BMC Research Notes
2011;4:147.
(11) Alatishe OI, Ndububa DA, Ojo OS, Agbakwuru EA, Adekanle O, Arowolo OA.
Pancreatic Cancer in Nigeria. Past, Present and Future. Nigerian Journal of
Gastroenterology and Hepatology 2009;2:61-73.
(12) Admassie D, Yesus H, Denke A. Validity of Ultrasonography in diagnosing
Obstructive Jaundice. East Africa Med J 2005;82:379-381.
(13) Bekele Z, Yifru A. Obstructive Jaundice in Adult Ethopians in a Referral
Hospital. Ethiop Med J 2000;38:267-275.
(14) Arvan DA. Diagnostic Strategies for Common Problems. In: Panzer RJ, Black
FR, Griner PF, eds. Philadephia Pa, American College of Physicians 1991:131-140.
(15) Mortele KJ, Ros PR. Anatomic Variants of the Biliary Tree. MR
Cholangiographic Findings and Clinical Applications. AJR 2001;177(2):389-394.
(16) Indkaghid ML. Anatomical Variations of the Extrahepatic Biliary Tree. Review of
the World Literature Clinical Anatomy 2001;14:167-172.
(17) Gilloteaux J. Introduction to the Biliary tract, The Gallbladder and Gall stones.
Microscopy Research and Technique 1997;38:547-551.
(18) Nakanuma Y, Hoso M, Sanzen T, Sasaki M. Microstructure and Development of
the Normal and Pathologic Biliary tracts in Humans, including blood supply.
Microscopy Research and Technique 1997;38:552-557.
(19) Pancreas or Hepatobiliary Liver Gallbladder Bile duct/ photography. Available at
duoliphotography.com/duou-photo/pancreas-or-hepatobiliary-liver-gall-bladder-
bile-duct.html.
70
(20) Ryan S, McNicholas M, Eustace S. Anatomy for Diagnostic Imaging second
edition. Saunders 2004 Elsevier limited. Chapter 5 pgs 176-182.
(21) Gohil YM, Patel SB, Goswamu KG, Shah S, Soni H. Ultrasonography in
Obstructive Jaundice. Indian J Radiol Imaging 2006;16(4):477-481.
(22) Siddique K, Ali Q, Mirza S, Jamil A, Ehsan A, Latif S, Malik AZ. Evaluation of
the Etiological Spectrum of Obstructive Jaundice. J Ayub Med Coll Abbottabad
2008;20(4):62-66.
(23) Bjornsson E, Gustafsson J, Borkman J, Kilander A. Fate of Patients with
Obstructive Jaundice. Journal of Hospital Medicine 2008;3:117-123.
(24) Rahman GA, Yusuf IF, Faniyi AO, Etonyeaku AC. Management of Patients with
Obstructive Jaundice: Experience in a developing Country. Nig Q J Hospital Med
2011;21(1):75-79.
(25) Lawal D, Oluwole S, Makanjuola D, Adekunle M. Diagnosis, Management and
Prognosis of Obstructive Jaundice in Ile-ife, Nigeria. West Afr J Medicine
1998;17(4):255-260
(26) Verma SR, Sahai SB, Gupta PK, Munshi A, Verma SC, Goyal P. Obstructive
Jaundice- Etiological Spectrum, Clinical, Biochemical and Radiological Evaluation
at a tertiary care Teaching Hospital. The Internet J of Tropical Med 2011; 7(2).
(27) Sharma MP, Ahuja V. Etiological Spectrum of Obstructive Jaundice and the
Diagnostic ability of Ultrasonography: A Clinician Perspective. Trop Gastroenterol
1999;20:167-169.
(28) Nizammuddin S, Ashraf MS, Islam UU, Rehman SU. Etiological Spectrum of
Obstructive Jaundice. Medical Channel 2010;16(2):299- 301.
71
(29) Feng G, Cai Y, Jia Z, Yang D, Chen H, Jin H et al. Interventional Therapy of
Malignant Obstructive Jaundice. Hepatobiliary Pancreatic Disease Int 2003;(2):300-
302.
(30) Mehrdad M, Seyed A, Marashi M, Taghi S, Mehrdad S. Obstructive Jaundice in
Iran: Factors affecting early outcome. Hepatobiliary Pancreat Dis Int 2008;7:515-
519.
(31) Aziz M, Ahmad N, Faizullah. Incidence of Malignant Obstructive Jaundice: A
study of hundred patients at Nishtar Hospital Mutari. AnnKE Med Coll 2004;10:71-
73.
(32) Krige JEJ, Shaw JM. Modern Imaging in Patients with Obstructive Jaundice.
CME 2007;25(7):328-331.
(33) Akhtar S, Mufti TS. Diagnostic Accuracy of Obstructive Jaundice on
Ultrasonography at Ayub hospital complex. J Ayub Med Coll Abbottabad
1999;11:45-46.
(34) Cheema KM, Ahmad F, Gonadal SH. Evaluation of Etiological Incidence and
Diagnostic Modalities in Obstructive Jaundice. Pak Post grad Med J 2001;12:160-
164.
(35) Upadhyaya V, Upadhyaya DN. Ansari MA, Shukia VK. Comparative Assessment
of Imaging Modalities in Biliary Obstruction. Indian J Radiol Imaging
2006;16:577-582.
(36) Ghimre R, Lohani B, Pradhan S. Accuracy of Ultrasonography in Evaluation of
level and cause of Biliary Obstruction; A prospective study. Kathmandu Univ Med
J 2005;3(1):17-21.
72
(37) Recaldini C, Carrafiello G, Bertolotti E, Angeretti MG, Fugazzola C. Contrast
Enhanced Ultrasonographic Findings in Pancreatic Tumors. Int J Med Sci
2008;5(4):203-208.
(38) Lencioni R, Cioni D, Bartolozzi C. Tissue Harmonic and Contrast- Specific
Imaging: back to gray scale in ultrasound. Eur Radiol 2002;12:151-165.
(39) D’ Onofrio M, Zamboni G, Tognolini A. Mass forming Pancreatitis: Value of
Contrast Enhanced Ultrasonography. World J Gastroenterol 2006;12:4181-4184.
(40) Robeldo R, Muro A, Prietom L. Extrahepatic Bile duct Carcinoma. Ultrasound
Characteristics and Accuracy in Demonstration of Tumors. Radiol 1989;172:689-
692.
(41) Yeo CJ, Pitt HA, Cameron JL. Cholangiocarcinoma. Surg Clin N Am 1990;
70:1429-1447.
(42) Sugiyama M, Atonu Y, Kuroda A, Muto T. Bile duct Carcinoma without
Jaundice: clues to early diagnosis. Hepatogastroenterol 1997;44:1477-1483.
(43) Anand MK, Nicholson DA. Cholangiocarcinoma Imaging. Available at
http://emedicine.medscape.com/article/365065-overview. (Accesses 12/4/2012)
(44) Bloom CM, Langer B, Wilson SR. Role of ultrasound in the Detection,
Characterization, and Staging of Cholangiocarcinoma. Radiographics,
1999;19:1199-1218.
(45) Choi BL, Lee JH, Han MC, Kim SH, Yi JG, Kim CW. Hilar
Cholangiocarcinoma: Comparative Study with Sonography and Computerized
Tommography. Radiol 1989;172:689-692.
73
(46) Lillemoe KD. Tumors of the Gallbladder, Bile ducts and Ampulla. Semin
Gastrointest Dis 2003;14:208-221.
(47) Wibulpolprasert B, Dhiensiri T. Peripheral Cholangiocarcinoma: Sonographic
Evaluation. J Clin Ultrasound 1992;20:303-314.
(48) Meyer D, Weinsten BJ. Klatskin tumors of the Bile ducts: Sonographic
appearance. Radiol 1983;148:803-804.
(49) Hann L, Greatrex K, Bach A, Fong Y, Blumgart L. Cholangiocarcinoma at the
Hepatic hilus: Sonographic Findings. AJR 1997;168:985-989.
(50) Shaffer EA. Choledocholithiasis and Cholangitis. Available at
http://www.merckmanual.com/professional/hepatic and biliary. (Accessed
5/4/2012)
(51) Eistein DM, Lapan SA, Ralls PW, Halls JM. The Insensitivity of Sonography in
the Detection of Choledocholithiasis. AJR 1984;142(4): 725-728.
(52) Ahn SI, Lee KY, Kim SJ. Surgical Clips found at the Hepatic duct after
Laparascopic Cholecystectomy: A possible case of clip migration. Surg Laparosc
Endosc percutan Tech 2005;15:279-282.
(53) Bhandari V, Singh M, Vyas HG, Sharma N, Chejara R. Diagnostic Dilemma in an
unusual case of Common Bile duct Obstruction. Gut and Liver 2011;5(2):245-247.
(54) Lai EC, Lau WY. Mirrizi Syndrome: History, Present and Future Development.
ANZ J Surg 2006;76(4):251-257.
(55) Al AM, Qais AM, Al KM, Gafour M, Al-Wadan AH. Biliary Ascariasis: The
value of ultrasound in the diagnosis and management. Ann Saudi Med
2007;27:161-165.
74
(56) Sur A, Bhatia M, Chander BN, Chaturvedi A. Hepatobiliary Ascariasis. Ind J
Radiol Imaging 2002;2(2):221-225.
(57) Khuroo MS, Zargar SA, Mahajan R, Bhat RL, Javid G. Sonographic appearance
in Biliary Ascariasis. Gastroenterol 1987;93(2):267-272.
(58) Baron RL, Stanley RJ, Lee JT. A Prospective Comparison; Evaluation of Biliary
Obstruction using Ultrasonography and Computed Tomography. Radiol.
1982;145:91-98.
(59) Syed N, Mohammed SA, Umair UI, Shafiq UR. Etiological Spectrum of
Obstructive Jaundice. Medical channel 2010;16:299-301.
(60) Huis M, Stulhofer M, Szerda F, Vukic T, Bubnjar J. Obstruction Icterus; Our
experience. Acta Med Croatica 2006;60(1):71-76.
(61) Zarin M, Ahmed M, Gohar A, Wah eed D, Khurram S et al. Incidence of gall
stones in carcinoma Gall Bladder patients. Pak J Surg 2005;21:19–22.
(62) Deitch EA. The Reliability and Clinical limitations of Sonographic Scanning of
the Biliary ducts. Ann Surg 1981;194(2):167-170.
(63) Honickman SP, Mueller PR, Wittenberg J, Simeone JF, Ferrucci JT, Cronan JJ et
al. Ultrasound in obstructive jaundice: prospective evaluation of site and cause.
Radiology. !983;147:511-515.
(64) Luke C, Price T, Karapetis C, Singhai N, Roder D. Pancreatic cancer
epidemiology and survival in an Australian population. Asian Pac J Cancer Prev
2009;10(3):369-374.
(65) Saini S. Imaging of the hepatobiliary tract. N Engl J Med 1997;336:1889-1894.
75
(66) Ahrendt SA, Pitt HA. Biliary tract In: Townsend C, ed. Sabiston Textbook of
Surgery. Philadephia: WB Saunders Company. 2001:1076-1111.
(67) Fernadez- Cruz L. Periampullary Carcinoma In: Holzheimer RG, Mannick JA ed.
Surgical Treatment: Evidence-Based and Problem Oriented. Munich:Zuckschwerdt;
2001. Available at http://www.ncbi.nlm.nih.gov/books/NBK6924/ (Accessed
21/4/2011)
(68) Ise N, Andoh H, Yasui O, Kurokawa T, Kotanagi H. Three cases of small
Hepatocellular carcinoma presenting as obstructive jaundice. HPB 2004;6(1):21-24.
(69) Cancer Facts and Figures. American Cancer Society. Available at http//www
cancer.Org/Research/Cancer Facts Figures/Index. (Accessed 10/7/2012).
(70) Lang FC, Brooke JR, Wing VW, Nyberg DA. Biliary dilatation: defining the level
and cause by real time ultrasound. Radiology 1986;160(1):39-42.
(71) Gibson RN, Yeung E, Thompson JN. Bile duct obstruction: radiologic evaluation
of level, cause and tumor resectability. Radiology 1986;160:43-47.
(72) Kumar M, Prashad R, Kumar A, Sharma R, Acharya SK, Chattopadhyay TK.
Relative merits of ultrasonography, computed tomography and cholangiography in
patients of surgical obstructive jaundice. Hepatogastroenterol 1998;45(24):2027-
2032.