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ObjectivesObjectives
• Goals of the 11-14 week scanGoals of the 11-14 week scan
• Fetal nuchal translucency in the detection of aneuploidyFetal nuchal translucency in the detection of aneuploidy
• The value of first trimester maternal serum markers in the detection of The value of first trimester maternal serum markers in the detection of aneuploidyaneuploidy
• Criteria for measurement of fetal nuchal translucencyCriteria for measurement of fetal nuchal translucency
• Pitfalls in the measurement of fetal nuchal translucencyPitfalls in the measurement of fetal nuchal translucency
• The significance of an increased nuchal translucency with a normal The significance of an increased nuchal translucency with a normal karyotypekaryotype
• Management of an increased nuchal translucency Management of an increased nuchal translucency
• Quality control of a nuchal translucency screening programQuality control of a nuchal translucency screening program
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Edchen99Edchen99提供提供
www.myfetus.netwww.myfetus.net
The goals of the 11-14 weeks scanThe goals of the 11-14 weeks scan
• Screening for trisomy 21 and other major chromosomal defectsScreening for trisomy 21 and other major chromosomal defects
• Early diagnosis of major abnormalities, e.g. anencephaly, exomphalosEarly diagnosis of major abnormalities, e.g. anencephaly, exomphalos
• Diagnosis of twins in about 2% of pregnancies & determination of chorionicityDiagnosis of twins in about 2% of pregnancies & determination of chorionicity
• Diagnosis of missed miscarriage in about 3% of pregnanciesDiagnosis of missed miscarriage in about 3% of pregnancies
• Early and accurate dating of pregnancy Early and accurate dating of pregnancy
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
3535 4545 5555 6565 7575 8585
Crown-rump length (mm)Crown-rump length (mm)
0.00.0
1.01.0
2.02.0
3.03.0
4.04.0
5.05.0
6.06.0
7.07.0
8.08.0
Nuchal translucency (mm)Nuchal translucency (mm)
• In normal pregnancies, fetal NT thickness increases with gestationIn normal pregnancies, fetal NT thickness increases with gestation• In trisomy 21 pregnancies fetal NT is increased (above the 95In trisomy 21 pregnancies fetal NT is increased (above the 95thth centile in about 75% of cases) centile in about 75% of cases)
Nuchal translucency as a function of crown-rump length Nuchal translucency as a function of crown-rump length (gestational age)(gestational age)
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Trisomy 21Trisomy 21
•The risk for trisomy 21 is derived by multiplying the The risk for trisomy 21 is derived by multiplying the a priori a priori maternal age and gestation-related risk by a likelihood ratio (LR)maternal age and gestation-related risk by a likelihood ratio (LR)• The LR depends on the degree of deviation in fetal NT from the expected normal median for that crown–rump length.The LR depends on the degree of deviation in fetal NT from the expected normal median for that crown–rump length.
Screening for trisomy 21Screening for trisomy 21
Assessment of risk by maternal age and fetal nuchal translucencyAssessment of risk by maternal age and fetal nuchal translucency
Risk (%)
Maternal age30 35 40 45
100
10
1
0.1
20 250.01
A priori riskA priori risk
NT
NT NT
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
20
0
2
4
6
8
10
12
14
16
18
-3.5 -2.5 -1.5 -0.5 0.5 1.5 2.5
PAPP-A (SD)
% Normal
PAPP-APAPP-A
0
2
4
6
8
10
12
14
16
18
20
-3.5 -2.5 -1.5 -0.5 0.5 1.5 2.5 3.5
Free ßhCG (SD)
% Normal
Free Free hCGhCG
Trisomy 21
Risk assessment with maternal serum free ß-hCG Risk assessment with maternal serum free ß-hCG && PAPP-A PAPP-A
Trisomy 21
• Alterations in maternal serum biochemistry are independent of fetal NT thickness Alterations in maternal serum biochemistry are independent of fetal NT thickness • Screening for trisomy 21 by a combination of fetal NT and maternal serum free ß-hCG and Screening for trisomy 21 by a combination of fetal NT and maternal serum free ß-hCG and
PAPP-A can identify about 90% of affected fetuses for a false positive rate of 5%.PAPP-A can identify about 90% of affected fetuses for a false positive rate of 5%.
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
100100,,000 pregnancies000 pregnancies
Maternal age Maternal age 606030%30%
Serum biochemistry at 16 wksSerum biochemistry at 16 wks 13013065%65%
Nuchal translucency (NT) at 12 wksNuchal translucency (NT) at 12 wks 75%75% 150150
Fetal NT & ß-hCGFetal NT & ß-hCG & PAPP- A at 12 wks & PAPP- A at 12 wks 18018090%90%
Screening for trisomy 21Screening for trisomy 21
Effectiveness of different methods of screeningEffectiveness of different methods of screening
Method of screeningMethod of screening Number detectedNumber detectedDetection rateDetection rate
Screen positive 5%Screen positive 5%N=5,000N=5,000
Trisomy 21Trisomy 21N=200N=200
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Maternal serum biochemistry and ultrasound parameters in the Maternal serum biochemistry and ultrasound parameters in the detection of chromosomal abnormalities other than trisomy 21detection of chromosomal abnormalities other than trisomy 21
Fetal heart Fetal heart raterate
Crown-rump Crown-rump lengthlength
Increased Increased NTNT Ultrasound markersUltrasound markersFree ß-hCGFree ß-hCG PAPP-APAPP-A
Trisomy 18Trisomy 18 75%75% ExomphalosExomphalosSingle umbilical arterySingle umbilical artery
X0 (Turner)X0 (Turner) 87%87%
Trisomy 13Trisomy 13 72%72% MegacystisMegacystisHoloprosencephalyHoloprosencephaly
TriploidyTriploidy 59%59% Small / molar placentaSmall / molar placenta / / / /
• Screening for trisomy 21 by a combination of fetal nuchal translucency and maternal serum free ß-hCG and Screening for trisomy 21 by a combination of fetal nuchal translucency and maternal serum free ß-hCG and PAPP-A can also identify about 90% of fetuses with other major chromosomal defectsPAPP-A can also identify about 90% of fetuses with other major chromosomal defects
• Each of these chromosomal defects is associated with its own syndromal pattern of sonographic and Each of these chromosomal defects is associated with its own syndromal pattern of sonographic and biochemical markersbiochemical markers
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Frequency of death and/or major anomaly in fetuses with Frequency of death and/or major anomaly in fetuses with an increased nuchal translucency and a normal karyotypean increased nuchal translucency and a normal karyotype
Death or major anomalyDeath or major anomaly
69%69%
> 6.5 mm
14%14%
3.5-4.42.5-3.4NTNT
3%3%
5.5-6.4
33%33%
4.5-5.4
23%23%
Souka et al. Ultrasound Obstet Gynecol 2001;18:9-17; n=1,320Souka et al. Ultrasound Obstet Gynecol 2001;18:9-17; n=1,320
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Achondrogenesis Achondrogenesis AchondroplasiaAchondroplasia
Asphyxiating thoracic dystrophyAsphyxiating thoracic dystrophyBlomstrand osteochondrodysplasiaBlomstrand osteochondrodysplasia
Campomelic dysplasiaCampomelic dysplasiaHypophosphatasiaHypophosphatasia
Jarcho-Levin syndromeJarcho-Levin syndromeNance-Sweeney syndromeNance-Sweeney syndromeOsteogenesis imperfectaOsteogenesis imperfecta
Roberts syndromeRoberts syndromeShort-rib-polydactily syndromeShort-rib-polydactily syndrome
SirenomeliaSirenomeliaThanatophoric dysplasiaThanatophoric dysplasia
CraniosynostosisCraniosynostosisIniencephalyIniencephaly
Agnathia/micrognathiaAgnathia/micrognathiaCardiac defectsCardiac defects
Diaphragmatic herniaDiaphragmatic herniaExomphalosExomphalosMegacystisMegacystis
Renal agenesisRenal agenesisPolycystic kidneysPolycystic kidneysMulticystic kidneysMulticystic kidneys
Nephrotic syndromeNephrotic syndromeBody stalk anomalyBody stalk anomaly
Congenital lymphedemaCongenital lymphedema
Akinesia deformation sequenceMyotonic dystrophy
Spinal muscular atrophy
Beckwith-Wiedemman syndrome Beckwith-Wiedemman syndrome GM1-gangliosidosisGM1-gangliosidosis
Mucopolysaccharidosis type VIIMucopolysaccharidosis type VIISmith-Lemli-Opitz syndromeSmith-Lemli-Opitz syndromeVitamin D resistant ricketsVitamin D resistant rickets
Zellweger syndromeZellweger syndrome
Blackfan Diamond anaemiaBlackfan Diamond anaemiaDyserythropoietic anaemiaDyserythropoietic anaemia
Thalassaemia-Thalassaemia-Parvovirus B19 infectionParvovirus B19 infection
Brachmann-de Lange syndromeBrachmann-de Lange syndromeCharge associationCharge associationdi George syndromedi George syndrome
EEC syndromeEEC syndromeFryn syndromeFryn syndrome
Noonan syndromeNoonan syndromePerlman syndromePerlman syndromeStickler syndromeStickler syndrome
Treacher-Collins syndromeTreacher-Collins syndromeTrigonocephaly C syndrome Trigonocephaly C syndrome
VACTER associationVACTER association
Conditions associated with increased nuchal Conditions associated with increased nuchal translucency and normal karyotypetranslucency and normal karyotype
Souka et al. Ultrasound Obstet Gynecol 2001;18:9-17Souka et al. Ultrasound Obstet Gynecol 2001;18:9-17
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
11-14 weeks11-14 weeksFetal karyotypingFetal karyotyping
Anomaly scanAnomaly scan
Chromosomal defectsChromosomal defectsMajor abnormalitiesMajor abnormalities
Normal karyotypeNormal karyotypeNo abnormalitiesNo abnormalities
14-16 weeks14-16 weeksAnomaly scanAnomaly scan
EchocardiographyEchocardiography
No abnormalitiesNo abnormalitiesResolving nuchalResolving nuchal
Major abnormalitiesMajor abnormalities
No abnormalitiesNo abnormalitiesPersistent nuchalPersistent nuchal
TORCH & Parvovirus screenTORCH & Parvovirus screenGenetic testingGenetic testing
20 weeks20 weeksAnomaly scanAnomaly scan
EchocardiographyEchocardiography
No abnormalitiesNo abnormalities
Major abnormalitiesMajor abnormalities
No abnormalitiesNo abnormalitiesPersistent nuchalPersistent nuchal
TORCH & Parvovirus screenTORCH & Parvovirus screenGenetic testingGenetic testing
Proposed management of increased nuchal translucencyProposed management of increased nuchal translucency
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Dichorionic 80%Dichorionic 80%
Monochorionic 20%Monochorionic 20%
Diagnosis of monochorionic or Diagnosis of monochorionic or dichorionic twinsdichorionic twins
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Frequency of complications as a function of Frequency of complications as a function of chorionicity in twin gestationschorionicity in twin gestations
2%2% 12%12%Miscarriage (11-23 weeks)Miscarriage (11-23 weeks)
1.5%1.5% 3%3%Perinatal death (>23 weeks)Perinatal death (>23 weeks)
10%10% 20%20%Fetal growth restrictionFetal growth restriction
5%5% 10%10%Preterm delivery (<32 weeks)Preterm delivery (<32 weeks)
DichorionicDichorionic MonochorionicMonochorionic
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Twins gestationTwins gestation
• Determine chorionicityDetermine chorionicity
• Measure nuchal translucency (NT) in each fetusMeasure nuchal translucency (NT) in each fetus
• Calculate the combined maternal age and fetal NT risk for each Calculate the combined maternal age and fetal NT risk for each fetusfetus
• The risk can be adjusted by multiplying with the likelihood ratio The risk can be adjusted by multiplying with the likelihood ratio derived from maternal serum free ß-hCG and PAPP-A derived from maternal serum free ß-hCG and PAPP-A
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Twin gestation: counsellingTwin gestation: counselling
Dichorionic twinsDichorionic twins
• Counsel the parents on the risks of having one or two affected fetusesCounsel the parents on the risks of having one or two affected fetuses
• If parents choose invasive testing the preferred option is chorionic villous If parents choose invasive testing the preferred option is chorionic villous sampling, because if one fetus is affected and the parents want selective sampling, because if one fetus is affected and the parents want selective fetocide the risk of miscarriage is considerably lower if fetocide is performed fetocide the risk of miscarriage is considerably lower if fetocide is performed in the first rather than the second trimester in the first rather than the second trimester
Monochorionic twinsMonochorionic twins
• Counsel the parents that Counsel the parents that the risk of both fetuses being affected is the the risk of both fetuses being affected is the average one derived from that calculated for each fetusaverage one derived from that calculated for each fetus
• If parents choose invasive testing the preferred option is chorionic villous If parents choose invasive testing the preferred option is chorionic villous sampling, because if the fetuses are affected the parents can have early sampling, because if the fetuses are affected the parents can have early terminationtermination
• If there is a large discordancy in NT between the two fetuses consider the If there is a large discordancy in NT between the two fetuses consider the diagnosis of twin-to-twin transfusion syndromediagnosis of twin-to-twin transfusion syndrome
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
• Theoretical course & examinationTheoretical course & examination• Practical training Practical training • Logbook of 10 imagesLogbook of 10 images
Install software for risk assessmentInstall software for risk assessment• Yearly auditYearly audit
• Distribution of NTsDistribution of NTs• Quality of 5 imagesQuality of 5 images
Training and quality assurance in the 11-14 Training and quality assurance in the 11-14 weeks scan by the Fetal Medicine Foundationweeks scan by the Fetal Medicine Foundation
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
• Principles of screening, pre-test and post-test counselling.Principles of screening, pre-test and post-test counselling. • Amniocentesis and chorionic villus sampling. Fetal cells and free DNA in maternal blood.Amniocentesis and chorionic villus sampling. Fetal cells and free DNA in maternal blood.
• FMF guidelines on the measurement of NT.FMF guidelines on the measurement of NT.
• Screening for chromosomal defects by fetal NT and maternal serum biochemistry.Screening for chromosomal defects by fetal NT and maternal serum biochemistry.
• Management of pregnancies with increased NT after the diagnosis of normal karyotype. Management of pregnancies with increased NT after the diagnosis of normal karyotype.
• Diagnosis and management of major fetal defects, such as anencephaly & exomphalos Diagnosis and management of major fetal defects, such as anencephaly & exomphalos These are found in about 1% of pregnanciesThese are found in about 1% of pregnancies
• Diagnosis of multiple pregnancies, determination of chorionicity and management.Diagnosis of multiple pregnancies, determination of chorionicity and management.These are found in about 2% of pregnancies.These are found in about 2% of pregnancies.
• Diagnosis and management of missed miscarriage detected at the 11-14 weeks scanDiagnosis and management of missed miscarriage detected at the 11-14 weeks scanThis is found in about 3% of pregnancies.This is found in about 3% of pregnancies.
Theoretical course: contentTheoretical course: content
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
• Gestation 11-14 wksGestation 11-14 wks• Crown-rump length 45-84 mmCrown-rump length 45-84 mm• Mid-sagittal viewMid-sagittal view• Image size: head and thoraxImage size: head and thorax• Neutral positionNeutral position• Away from amnionAway from amnion• Maximum lucencyMaximum lucency• Callipers on-to-onCallipers on-to-on
Criteria for proper measurement of Criteria for proper measurement of nuchal translucencynuchal translucency
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
The image should have the head and thorax onlyThe image should have the head and thorax only
Each movement of the calliper gives a 0.1 mm Each movement of the calliper gives a 0.1 mm change of the measurementchange of the measurement
Measurement of nuchal translucencyMeasurement of nuchal translucencyThe importance of The importance of image magnificationimage magnification
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
HyperextendedHyperextended
Measurement of nuchal translucencyMeasurement of nuchal translucencyHead positionHead position
Hyperextended head may falsely increase NT measurementHyperextended head may falsely increase NT measurement
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Measurement of nuchal translucencyMeasurement of nuchal translucencyMid-sagittal sectionMid-sagittal section
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Measurement of nuchal translucency: Measurement of nuchal translucency: calliper placementcalliper placement
UnderestimateUnderestimate
OverestimateOverestimate
Correct Correct
(inner-to-inner)(inner-to-inner)
Correct placement of the callipers Correct placement of the callipers to assess nuchal translucency to assess nuchal translucency
based upon published nomograms based upon published nomograms by the Fetal Medicine Foundationby the Fetal Medicine Foundation
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
CRL: 54 mmCRL: 54 mm
Risk (%)
Age (years)
30 35 40 45
100
10
1
0.1
20 25
0.01
1: 6001: 600
1: 3,7001: 3,7001.51.5
1: 1001: 100
2.92.9
The correct measurement is 2.9The correct measurement is 2.9
Measurement of nuchal translucencyMeasurement of nuchal translucencyUse the longest measurementUse the longest measurement
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
A nuchal cord is found in 5% of casesA nuchal cord is found in 5% of cases
Measure the NT above and below the umbilical cord and use the average Measure the NT above and below the umbilical cord and use the average measurement for calculation of riskmeasurement for calculation of risk
Measurement of nuchal translucency in Measurement of nuchal translucency in the presence of a nuchal cordthe presence of a nuchal cord
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Criteria to obtain and maintain certificationCriteria to obtain and maintain certification
Submit 10 images for review by quality control centerSubmit 10 images for review by quality control center
• True sagittal sectionTrue sagittal section• Image size: head & thoraxImage size: head & thorax• Neutral positionNeutral position• Callipers on-to-onCallipers on-to-on• Maximum lucency Maximum lucency
Criteria for evaluating the images by the quality control center Criteria for evaluating the images by the quality control center (Fetal Medicine Foundation)(Fetal Medicine Foundation)
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
1. PASS: All 5 criteria fulfilled in at least 8 of the 10 images1. PASS: All 5 criteria fulfilled in at least 8 of the 10 images
2. 3-5 unsatisfactory images: Submit another 5 images2. 3-5 unsatisfactory images: Submit another 5 images
3. 6-10 unsatisfactory images: Submit another 10 images3. 6-10 unsatisfactory images: Submit another 10 images
Evaluation of the images and actionEvaluation of the images and action
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
0.0
1.0
2.0
3.0
4.0
5.0
6.0
45 50 55 60 65 70 75 80 85
Crown- rump length (mm)
Nu
chal
tra
nsl
uce
ncy
(m
m)
40-60% of measurements above the median40-60% of measurements above the median
ACTION: Renew license of the software for 1 yearACTION: Renew license of the software for 1 year
Audit of distribution of nuchal translucency Audit of distribution of nuchal translucency measurements for renewal of certificationmeasurements for renewal of certification
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
Under-estimatingUnder-estimating
0.0
1.0
2.
3.0
4.0
45 50 55 60 65 70 75 80 85
Crown- rump length (mm)
Nu
chal
tra
nsl
uce
ncy
(m
m)
>60% of measurements >60% of measurements belowbelow the median the median
ACTION: Renew license of the software for 3 months only and reassessACTION: Renew license of the software for 3 months only and reassess
0.0
1.0
2.0
3.0
4.0
45 50 55 60 65 70 75 80 85
Crown- rump length (mm)N
uch
al t
ran
slu
cen
cy (
mm
)
Over-estimatingOver-estimating
>60% of measurements >60% of measurements aboveabove the median the median
Audit of distribution of nuchal translucency Audit of distribution of nuchal translucency measurements for renewal of certificationmeasurements for renewal of certification
Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004Nicolaides KH. Fetal nuchal translucency. Am J Obstet Gynecol 2004
For more images and information of the 11-14 For more images and information of the 11-14 weeks scan, the reader is referred toweeks scan, the reader is referred to
The 11-14 Week ScanThe 11-14 Week ScanThe Diagnosis of Fetal AbnormalitiesThe Diagnosis of Fetal Abnormalities
at the following website:at the following website:
http://www.fetalmedicine.com/f-books11-14.htm
The material is freely available for reviewThe material is freely available for review