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TiP-TV® Training in PartnershipProgram Supplement and Testfor Imaging Professionals

XR: Introduction to Interventional Radiology

Publication Date: February 5, 2009

1.0 ASRT-approved Category A CE Credit

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GE Healthcare XR: Introduction to Interventional Radiology

REV 0 Program Supplement and Test

TABLE OF CONTENTS

Program Summary.......................................................................................................................................................................3Continuing Education Credit and Video File Download (**NEW**) ..........................................................................4Introduction.....................................................................................................................................................................................5History of IR .....................................................................................................................................................................................5

Radiology and Interventional Milestones ....................................................................................................................5IR Equipment, Accessories, and Team .................................................................................................................................7

Imaging Equipment ..............................................................................................................................................................7Digital Subtraction ................................................................................................................................................................8Interventional Tools ..............................................................................................................................................................8The Interventional Radiology Team ...............................................................................................................................9

IR Procedures .............................................................................................................................................................................. 10Case Studies................................................................................................................................................................................. 13Appendix A: Presenters ................................................................................................................................................................... 15Appendix B: Resources .................................................................................................................................................................... 15Appendix C: Glossary ........................................................................................................................................................................ 16Appendix D: Post-Test ...................................................................................................................................................................... 18

© 2009 General Electric Company. All rights reserved. 2 of 20



Program Summary

This page provides an overview of the program content and learning objectives. The Table of Contents provides a detailed list of the topics covered. Please keep a copy of this Program Summary and the Table of Contents with your continuing education certificate. It is also recommended that you provide a copy of this information to your manager as a record of your educational achievement.

Program Description and Target Audience

Diagnostic imaging professionals seeking new challenges may find them within the world of interventional radiology (IR). But if you are not quite sure if IR is right for you, this program presents an interventional radiologist who describes what it is like to practice in this imaging specialty. Also discussed are the history of interventional radiology, common practices and procedures, the role of the technologist , and case presentations.

The course objectives specifically target radiologic technologists considering a change to interventional imaging.

Program Objectives

By the end of this program, the viewer should be able to:

1. Discuss the achievements made by key contributors to the field of interventional radiology.

2. Identify the modern IR practice model.

3. Describe the basic equipment and instruments used during interventional radiology procedures.

4. State the role of the radiologic technologist in interventional radiology.

5. Explain several procedures commonly performed in the IR suite.

Continuing Education Credit

1.0 ASRT-approved Category A CE Credit

NOTE: While the technical content is most effective for the target audience, other technologists and medical personnel may also benefit from viewing this course. Regardless of your imaging specialty, you may apply for continuing education credit . Refer to the Continuing Education Credit page for additional information.




Continuing Education Credit and Video File Download (**NEW**)

Online Process for CE Credit (hls.gehealthcare.com)

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1. View the entire program video online or download the video file for later viewing (refer to the process below). This supplement is not intended to replace watching the video.

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5. Florida residents: The process for submitting CE credit to the FL DOH can be found onlinein the Related Documents tab on the bottom of the program’s Item Details page.

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Introduction

Interventional radiology is a relatively young medical specialty, but one that has had a great impact on today’s clinical medical environment. Many interventional techniques use catheters and instruments small enough to be passed through a patient's arteries and veins to access and treat a diseased area within the body. The fact that many conditions previously corrected with open surgery are now treated with minimally invasive interventional procedures, makes IR a major advance in medicine for patients.

This program chronicles a lecture given by Dr. James Walker at an educational session of the Wisconsin Society of Radiologic Technologists. Dr. Walker is an interventional radiologist with Milwaukee Radiologists Ltd., providing IR services at two major hospitals in southeastern Wisconsin. Dr. Walker addresses the following topics:• The history of interventional radiology.• Basic equipment used during interventional procedures.• An explanation of a variety of procedures.• Specific case studies.

NOTE: Dr. Walker displays and discusses a number of interventional accessories and procedures. Due to the image rich nature of the program, it is necessary to view the video to completely comprehend the content.

History of IR

Interventional radiologists are board certified physicians with advanced training in image-guided, minimally invasive, targeted treatments. Their knowledge of all the imaging modalities, coupled with their experience using catheters and angiographic tools, laid the groundwork for non-surgical intervention. A bit of history helps to understand the transition from diagnostic to interventional radiology.

Radiology and Interventional Milestones

• 1895 – Wilhelm Roentgen discovers x-ray.

• 1896 – the limitations of x-ray were recognized because of the inability to see soft tissue and blood vessels.– Haschek and Lindenthal perform the first angiogram on an amputated hand.

• 1929 – Dr. Werner Forssmann performs the first right heart catheterization, on himself!

• 1930s – Dr. Egas Moniz performs the first neuroangiography on a live patient.




• 1953 – Dr. Sven Seldinger invents a method to safely introduce a catheter into a blood vessel.– A needle is placed in the blood vessel, a wire is put through the needle, the needle is removed, and a

catheter is put over the wire. – With this safe, reproducible technique, angiography, angioplasty, and other procedures flourished.

• 1964 – Dr. Charles Dotter performs the first angioplasty.

• 1970s – American physicians develop a method for embolizing bleeding ulcers, performing coronary angiography, and angioplasty.

After Dr. Dotter, in the late half of the 20th century, the field of interventional radiology flourished. The procedures were very effective with a favorable side effect profile. At this time, the interventional radiologist generally did not see the patient in advance of the procedure or in follow-up, therefore they were considered to be a proceduralist rather than a clinical doctor. Today’s interventional radiologist is more clinical. They see patients in consultation and follow-up, and provide services in hospitals.

Notes:

"The angiographic catheter can be more than a tool for passive means for diagnostic observation. Used with imagination, it can become an important surgical instrument."

Dr. Charles Dotter – 1963The Father of Interventional Radiology




IR Equipment, Accessories, and Team

Imaging Equipment

Today’s cardiovascular imaging systems are technologically sophisticated and completely digital. C-arm systems are extremely flexible and with this type of system, an x-ray tube and a digital detector are mounted on opposite sides of a c-shaped arm. As the c-arm moves, the tube and detector maintain the same relationship to each other.

Fluoroscopy, as well as image acquisition, occurs with this tube and detector. Single plane systems are architected with one c-arm, one tube, and one detector.

With a bi-plane system, there are two c-arms, each equipped with an x-ray tube and digital detector. Bi-plane systems are frequently used when performing neurovascular interventions, when it is necessary to visualize the anatomy in two different planes simultaneously, such as in frontal and lateral projections. With bi-plane units, it is also possible to obtain both the lateral and frontal image acquisitions with one contrast injection.

Another feature unique to many bi-plane systems is the ability to move one of the arms out of the way into a "park" position, so you can operate the system as a single plane device.

Detector

Figure 1 GE InnovaTM Single Plane System

X-ray tube

Figure 2 GE InnovaTM Bi-Plane System




Digital Subtraction

Digital subtraction is an imaging technique designed to reduce anatomical clutter in radiographic images. It is very commonly used in angiographic (angio) imaging to have an unobstructed view of the contrast-filled vessels. When images are acquired digitally, the subtraction process is performed automatically and directly by a computer.

Very simply, a mask image of the area containing all the anatomic detail is obtained, just prior to a contrast injection. The mask image data is then mathematically "subtracted out" from each of the images containing contrast, with the remainder being an image that demonstrates only the contrast-filled vessels.

Subtracted fluoroscopy is a feature that may be available on more current cardiovascular imaging systems. As the name infers, a subtracted fluoroscopic image, without anatomical clutter, is available for the interventional radiologist to view.

There are several other imaging techniques that may be available on current cardiovascular systems, such as three-dimensional (3-D) angiography and angio CT. With these techniques, the c-arm gantry of a single plane system is capable of acquiring images as it moves rapidly in an arc around the patient. This is called spin or rotational imaging. The image data can then be formatted into either a 3-D representation or a CT-like image.

Interventional Tools

Needles

The standard needle set is the 21-gauge micropuncture set.

Wires

• The diameter of the wire is measured in hundredths of an inch.

• Standard length is 145 centimeters (cm).

Sheaths

• The purpose of a sheath is to traumatize the vessel only one time. Catheters and wires are then passed through the sheath so the blood vessel will be bothered only once.

• Sheath is measured in French and one French is 0.33 millimeter (mm).

The French Gauge system is commonly used to measure the outer diameter of cylindrical medical instruments. The system was devised by Joseph-Frédéric-Benoît Charrière, a 19th century Parisian maker of surgical instruments. The diameter of a catheter, in millimeters, can be determined by dividing the French size by 3.

Catheters

• A variety of sizes and shapes are available.

• The type used depends on the interventionalist and the vasculature.

• Microcatheter is a generic term for a catheter that is less than 3 French (1 mm).




Balloons

• These are used to dilate tubular structures that have narrowed. This includes, but is not limited to arteries, veins, ureters, and bile ducts.

• A variety of diameters and shapes are available.

Stents

These are small, flexible tubes made of plastic or wire mesh, and generally used to hold open vessels or other tubular structures that are narrowed or blocked.

Embolics

• These are devices or materials used to intentionally clot off blood vessels, typically in the case of unwanted bleeding.

• Coils, gelfoam pledgets, or other particles can be used to embolize vessels.

The Interventional Radiology Team

The IR team generally consists of a physician who performs the procedure, a nurse who monitors blood pressure and administers medications, and the technologist who handles all remaining functions. Depending on the facility, a physician assistant or fellow or resident may also participate in the procedure.

The IR technologist performs multiple roles during an interventional procedure.

• Prepatory– Prepare and set up the interventional suite.– Patient preparation and follow-up care (close and/or dress wound).

• Technical

Assist and run the imaging equipment.

• Intellectual– Problem solve.– Suggest new equipment and/or techniques.

Notes:




IR Procedures

Interventions can be performed in many areas of the body and in most organ systems, with imaging being a critical component during each procedure. The following list identifies common interventional procedures.

Arterial Interventions• Diagnostic angiograms

– Performed less frequently given the availability of computed tomography angiography (CTA) and magnetic resonance angiography (MRA) technology.

• Angioplasty

• Stenting

• Atherectomy

• Cryoplasty

• Laser

Venous Interventions

• Dialysis fistula maintenance

• Venous angioplasty/stenting

• Thrombolysis

• Inferior vena cava (IVC) filter placement and removal

Gastrointestinal (GI) Bleeding

• Emergent procedures

• Embolize a bleeding vessel to the bowel.– Bleeding ulcer, diverticulitis, etc.

• Perform an intrahepatic portosystemic shunt (TIPS) to treat variceal bleeding.– A TIPS is a stent that is placed in veins in the middle of the liver to improve blood flow to and from the

organ.– Patients who typically need a TIPS, are cirrhotic with portal hypertension (increased pressure in the

portal vein).– Portal hypertension causes blood to flow backward from the liver into the veins of the stomach, lower

esophagus, and intestines, causing enlarged vessels (varices), bleeding, and the accumulation of fluid in the chest or abdomen.

– A tunnel is made through the liver to connect the portal vein (the vein that carries blood from the digestive organs to the liver) to one of the hepatic veins (three veins that carry blood away from the liver). A stent is then placed in this tunnel to keep the pathway open.




Venous Access

Central venous access catheters (CVAC) are inserted into the body so patients can receive medication or nutrients directly into the bloodstream or gastrointestinal system, or so blood can be drawn, sparing the patient from repeated needle sticks. Physicians often recommend CVACs for patients who require regular chemotherapy treatments, antibiotic or medication infusions, nutritional supplements, or hemodialysis. Examples of CVACs include:

• Peripherally inserted central catheters (PICCs). Sometimes called long lines.– Long, thin lines designed for placement in one of the larger veins near the heart .

Used when a person needs intravenous medication, chemotherapy, or fluids for an extended period of time.Typically, these types of medications quickly cause smaller veins to clot off, so they must be delivered into the larger veins closer to the heart . May also be used when someone requires frequent blood sampling.

• Ports (implantable)

• Dialysis catheters

• Total parenteral nutrition (TPN) lines

• Others

Drainages

• Abscess drains

• Chest tubes

• Percutaneous nephrostomies/stents

• Biliary drains/stents

• Gastrostomy tubes

With some medical conditions, it is necessary to place a catheter into an organ or body cavity to remove unwanted fluids such as blood or urine. If it is required that the drainage occurs over an extended period of time, such as days, weeks, or even months, it is necessary to properly secure the catheter in the drainage site. This is accomplished by using a Cope loop or lockable pig-tail catheter. With this type of catheter, the interventional radiologist is capable of forming a curl at its distal end, thereby creating an efficient means to prevent the catheter from being dislodged.

Biopsies

Depending upon the facility, biopsies may be performed by either an interventional radiologist or a body radiologist .

Interventional Oncology

• Many new minimally-invasive techniques.

• Directly target cancer in the lung, liver, and kidneys.




• Local ablation– Less invasive, shorter recovery time.– Imaging is used to confirm treatment zone.– Radio frequency ablation (RFA) = burn it .– Cryoablation = freeze it .

• Arterial treatments– Chemoembolization– Radioembolization– Allows high dose chemotherapy (or radiation) directly into the tumor, without the systemic side effects.

Uterine Fibroid Embolization (UFE)

• Benign tumors of uterus

• Very common in 30- to 50-year-old women.

• Symptoms:– Heavy bleeding– Bulk symptoms (urinary, constipation)– Pain and cramping– Infertility

Pain Management

• Vertebroplasty

• Kyphoplasty

• Epidural steroid injections

• Nerve blocks

• Facet blocks

• Numerous other pain procedures

Varicose Vein Treatments

• Endovenous laser ablation, sometimes called endovenous laser therapy (EVLT).– Modern alternative to “stripping.”– Destroy refluxing veins with heat.

• Ambulatory phlebectomy– Removal of bulging varicose veins.– Microincisions (1 to 2 mm)

• Sclerotherapy– Injecting veins with a detergent to occlude them.




Case Studies

Case One

• Seventy-five-year-old woman.

• Progressive abdominal pain, especially post-prandial.

• Fifteen pound weight loss over six months.

• Pertinent medical history: coronary artery disease, hypertension.

• Long history of smoking. Quit five years ago.

• Colonoscopy: ischemic colitis of cecum.

• One month follow-up:– Resolved abdominal pain.– Gained weight.

• Mesenteric ischemia MRA/CTA– Confirm diagnosis.– Determine measurements (diameter/length stent needed).– Evaluate all three mesenteric vessels.– Evaluate for other causes of pain.

Case Two

• Fifty-five-year-old man.

• CT scan for abdominal pain. Cause not seen.

• Incidental 2.5 cm right upper pole solid renal mass.

• No other significant findings.

• Presumed renal cell carcinoma.– Options:

Partial nephrectomy.Nephrectomy.Local ablation (cryoablation/RFA).Watchful waiting.

• Pertinent medical history: coronary artery disease, coronary artery bypass graft surgery, low ejection fraction (i.e., not a surgical candidate).

• Referred for cryoablation.

• When performing interventional oncology:– Obtain pre- and post-contrast enhanced CT / MRI.

Response based on the degree of enhancement.Size of lesion is secondary (i.e., the treatment zone is intentionally larger than the tumor).Distinguish calcification/blood from tumor.




Case Three

• Eighty-three-year-old woman.

• Chief complaint: progressive low back pain.

• Refractory to narcotics.

• Pertinent medical history: osteoporosis, atherosclerosis.

• Lumbar spine films obtained, no films available for comparison.

• Requested to perform kyphoplasty at eleventh thoracic (T11) and first lumbar (L1) vertebral segments.

• Physical exam findings:– Diffuse spinal and paraspinal tenderness.– Negative straight leg raise.– No weakness.

• Next step:– Imaging to determine chronicity of fractures.

MRI.Bone scan.

• Follow-up: – Significant improvement in pain.– Off narcotics.

• Before performing vertebral augmentation:– Advanced imaging is essential (especially MRI).– Avoid unnecessary procedures.– Increase success rates.– MRI: Stir/T2 fat saturation; post gadolinium.

Notes:




Appendix A: Presenters

Kit Czarnecki, B.A., R.T. (R)X-ray TiP-TV Program ManagerGE Healthcare

James M. Walker, M.D.Interventional RadiologistMilwaukee Radiologists, Ltd.Milwaukee, Wisconsin

Appendix B: Resources

Resource used by Dr. Walker

Rosch, J., Keller, F., and Kaufman, J., "The Birth, Early Years, and Future of Interventional Radiology," Journal of Vascular and Interventional Radiology, 2003, 14: 841-853.

Electronic Resources

American College of Radiology: http://www.acr.org

AngioDynamics® Incorporated: http://www.angiodynamics.com

Medcyclopaedia: http://www.medcyclopaedia.com

Merriam-Webster OnLine: http://www.merriam-webster.com/dictionary/

Society of Interventional Radiology: http://www.sirweb.org

NOTE: The Internet is an ever-evolving environment and links are subject to change without notice.




Appendix C: Glossary

angioplasty: a technique to mechanically widen a blood vessel that is narrowed or totally obstructed.

anomaly: deviation from the average or norm; anything structurally unusual or irregular or contrary to a general rule.

atherosclerosis: arteriosclerosis characterized by irregularly distributed lipid deposits in the intima of large and medium-sized arteries. Such deposits are associated with fibrosis and calcification.

CABG: coronary artery bypass graft

CAD: coronary artery disease

cannulate: to insert a cannula (catheter) into a cavity, duct, or vessel for the drainage of fluid or the administration of medication (contrast).

cirrhosis: a consequence of chronic liver disease characterized by replacement of liver tissue by fibrous scar tissue as well as regenerative nodules (lumps that occur as a result of a process in which damaged tissue is regenerated) leading to progressive loss of liver function.

claudication (intermittent): cramping pain and weakness in the legs and especially the calves on walking that disappears after rest and is usually associated with inadequate blood supply to the muscles.

cryoplasty: a type of therapy for vascular disease that both cools and dilates a stenosed vessel at the same time.

CT: computed tomography

CTA: computed tomography angiography

embolization: therapeutic introduction of various substances into the circulation to occlude vessels, either to arrest or prevent hemorrhaging or to devitalize a structure or organ by occluding its blood supply.

empyema: the presence of pus in a bodily cavity (as the pleural cavity).ethiodol: brand of ethiodized oil that is a sterile injectable radiopaque diagnostic agent, typically used in

hysterosalpingography and lymphography.

ischemia: deficient supply of blood to a body part (as the heart or brain) that is due to obstruction of the inflow of arterial blood (as by the narrowing of arteries by spasm or disease)

methacrylate: polymethyl methacrylate (PMMA); bone cement.

MRA: magnetic resonance angiography

phlebectomy: excision of a segment of a vein, performed sometimes as a cure for varicose veins.

PMH: pertinent medical history

postprandial: after a meal.

PTFE: polytetrafluorethylene; a synthetic material used in the production of arterial prostheses (grafts).

RFA: radio frequency ablation




sclerotherapy: a technique where a vein is injected with a chemical solution which causes the vessel to stick together. As a result , the treated vessel can no longer hold blood. It shrivels and is eventually reabsorbed by the body. Sclerotherapy is used to treat spider veins and small varicose veins.

splenomegaly: enlarged spleen.

stenosis: a constriction or narrowing of a duct or passage; a stricture.

thrombolysis: destruction of a thrombus or blood clot .

TIPS: transjugular intrahepatic portosystemic shunt

UFE: uterine fibroid embolization

varices: abnormally dilated and lengthened veins, arteries, or lymph vessels; especially varicose veins.




Appendix D: Post-Test

To be eligible for CE credit , you MUST view the video presentation first . Then complete the post-test on the GE Healthcare Learning System (hls.gehealthcare.com) by the due date listed online.

XR: Introduction to Interventional Radiology LMS Course Number: 3374

1. In 1953, Dr. _____ invented a method to safely introduce a catheter into a blood vessel. a. Seldingerb. Dotterc. Forssmannd. Egas-Moniz

2. Dr. _____ is often referred to as the father of interventional radiology. a. Seldingerb. Dotterc. Gruntzigd. Lindenthal

3. The diameter of wires used during interventional radiology procedures is measured in _____. a. Frenchb. millimetersc. hundredths of an inchd. centimeters

4. A _____ is used so that the blood vessel is traumatized only once during an interventional procedure. a. balloonb. catheterc. wired. sheath

5. One French is equal to _____ mm. a. 0.33 b. 0.50c. 1d. 2

6. Microcatheter is a generic term for a catheter that is less than _____ French. a. 1b. 2c. 3d. 4

7. _____ are small, flexible tubes made of plastic or wire mesh, used to hold open vessels or other tubular structures that are narrowed or blocked. a. Balloonsb. Stentsc. Embolicsd. Cryonics




8. _____ are devices or materials used to intentionally clot off blood vessels, typically in the case of unwanted bleeding. a. Stentsb. Cathetersc. Balloonsd. Embolics

9. According to Dr. Walker, the interventional imaging technologist has three roles: prepatory, technical, and intellectual. a. Trueb. False

10. _____ is an interventional procedure that removes hard plaque in the blood vessels by passing it through a catheter and out of the body. a. UFEb. Atherectomyc. Thrombolysisd. Angioplasty

11. During a/an _____ procedure, a shunt is placed between the portal and hepatic veins to decrease the pressure in the portal venous system. a. UFEb. PICCc. TIPSd. IVC filter

12. _____ is/are a common symptom of portal hypertension. a. Claudicationb. Non-healing foot ulcersc. Ureteral fibroidsd. Variceal bleeding

13. All of the following are considered venous access devices, EXCEPT a/an _____. a. chest tubeb. PICC linec. dialysis catheterd. implantable port

14. _____ are long lines placed near the heart and commonly used to deliver antibiotics or chemotherapy, or when frequent blood sampling is required. a. Stentsb. PICC linesc. IVC filtersd. Chest tubes

15. Once a _____ catheter has been positioned, the distal end of the catheter can be curled so that it remains in place. a. Seldingerb. Dotterc. Cope loopd. PICC




16. When performing an arterial chemoembolization, _____ is added to the chemotherapy agent in order to demonstrate radiographically that the tumor has been effectively targeted. a. polyvinyl alcoholb. methacrylatec. detergentd. ethiodol

17. Radio frequency ablation destroys a tumor by freezing it . a. Trueb. False

18. Which of the following statements is NOT representative of the UFE procedure? a. Uterine fibroids are hypovascular.b. Blood vessels that feed uterine fibroids are embolized with PVA particles or microspheres.c. This procedure is an alternative to hysterectomy or myomectomy.d. Magnetic resonance imaging is obtained before and several months after the procedure.

19. _____ is a procedure that uses heat from a laser to destroy the inner lining of a varicose vein so that it is no longer a conduit for blood. a. Sclerotherapyb. Phlebectomyc. EVLTd. Kyphoplasty

20. _____ may occur when the blood supply is acutely returned to previously ischemic tissues. a. Pulmonary embolusb. Hypertensionc. Atherosclerosisd. Reperfusion edema
