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Textbook of

COLOR DOPPLER IMAGING

Jayp

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Textbook of

COLOR DOPPLER IMAGING

JAYPEE BROTHERS MEDICAL PUBLISHERS (P) LTDNew Delhi • St Louis (USA) • Panama City (Panama) • London (UK) • AhmedabadBengaluru • Chennai • Hyderabad • Kochi • Kolkata • Lucknow • Mumbai • Nagpur

®

Satish K BhargavaMD(Radiodiagnosis) MD(Radiotherapy)DMRD FICRI FIAMS FCCP FUSI FAMS

Professor and HeadDepartment of Radiology and ImagingUniversity College of Medical Sciences(University of Delhi) and GTB Hospital

Dilshad Garden, Delhi, India

Second Edition

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Published by

Jitendar P VijJaypee Brothers Medical Publishers (P) Ltd

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Textbook of Color Doppler Imaging

© 2010, Satish K Bhargava

All rights reserved. No part of this publication should be reproduced, stored in a retrieval system, or transmitted in any form or by any means:electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the editor and the publisher.

This book has been published in good faith that the material provided by the contributors is original. Every effort is made to ensure accuracy ofmaterial, but the publisher, printer and editor will not be held responsible for any inadvertent error (s). In case of any dispute, all legal mattersare to be settled under Delhi jurisdiction only.

First Edition: 2003

Reprint: 2007

Second Edition: 2010

ISBN 978-81-8448-996-5

Typeset at JPBMP typesetting unit

Printed at

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My loving late wife

Kalpana

and my son

Sumeet

Whose inspiration and sacrifice

have made possible to bring out this book

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Contributors

AK Srivastava MSc Phd

PhysicistDepartment of Radiology andImaging, University College ofMedical Sciences (University ofDelhi) and GTB HospitalDilshad Garden, Delhi, India

Bharat ParekhMD (Radiodiagnosis) FICRI

ChairmanIndian College of Radiology andImaging and Consultant RadiologistECLAT Poly Clinic, Mumbai, India

Deep N Srivastava MD (Radiodiagnosis)

ProfessorDepartment of RadiodiagnosisAll India Institute of Medical SciencesAnsari Nagar, Delhi, India

Gopesh Mehrotra MD (Radiodiagnosis)

Professor, Department of Radiologyand Imaging, University College ofMedical Sciences (University of Delhi)and GTB Hospital, Dilshad GardenDelhi, India

GP Vashisht MD (Radiodiagnosis) FICRI

DirectorDepartment Radiology and ImagingBatra Hospital and Medical ResearchCentre, Delhi, India

Gurpreet Gulati MD (Radiodiagnosis)

Associate ProfessorDepartment of Cardiac-RadiologyAll India Institute of Medical SciencesAnsari Nagar, Delhi, India

Jaideep MalhotraMD FICOG FIAJAGO FICMCH FICMU

Malhotra Nursing and MaternityHome (P) Ltd, Agra, Uttar PradeshIndia

Lalendra UpretiMD (Radiodiagnosis) DNB

ProfessorDepartment of RadiodiagnosisMaulana Azad Medical College andAssociated, GB Pant HospitalDelhi, India

Narendra MalhotraMD FICOG FIAJAGO FICMCH FICMU

Malhotra Nursing and MaternityHome (P) Ltd, Agra, Uttar PradeshIndia

OP SharmaMD (Radiodiagnosis) PhD (Radiology) FICRI

ProfessorDepartment of Radiodiagnosis andImaging, Institute of MedicalSciences, Banaras Hindu UniversityVaranasi, Uttar Pradesh, India

Poonam Narang MD (Radiodiagnosis)

ProfessorDepartment of RadiologyMaulana Azad Medical College andAssociated GB Pant HospitalNew Delhi, India

Rajul Rastogi MD (Radiodiagnosis)

Ex-ResidentDepartment of Radiology andImaging, University College ofMedical Sciences(University of Delhi) andGTB Hospital Dilshad GardenDelhi, IndiaAnd Now As–Head, Department ofRadiology and ImagingYash Diagnostic Center,Civil Lines,Moradabad, Uttar Pradesh, India

Rohini Gupta MD (Radiodiagnosis)

Assistant ProfessorDepartment of Radiodiagnosis and

Imaging, Vardhman MahavirMedical College andAssociated Safdarjung HospitalDelhi, India

Sanjay Thulkar MD (Radiodiagnosis)

ProfessorDepartment of RadiodiagnosisAll India Institute of MedicalSciences, Ansari NagarDelhi, India

Sanjiv Sharma MD (Radiodiagnosis)

HeadDepartment of Cardiac-RadiologyAll India Institute of Medical SciencesAnsari Nagar, Delhi, India

Satish K BhargavaMD(Radiodiagnosis) MD (Radiotherapy)DMRD FICRI FIAMS FCCP FUSI FAMS

Professor and HeadDepartment of Radiology andImaging University College ofMedical Sciences (University of Delhi)and GTB HospitalDilshad Garden, Delhi, India

Suchi BhattMD(Radiodiagnosis) FICRI MNAMS

Reader, Department of Radiologyand Imaging, University College ofMedical Sciences (University ofDelhi) and GTB Hospital, DilshadGarden, Delhi, India

Sumeet BhargavaDNB (Radiodiagnosis) MNAMS FCGP

Senior ResidentAll India Institute of Medical Sciences,Ansari Nagar,New Delhi, India

Vipul Gupta MD (Radiodiagnosis)

Head,Department of Neuro-RadiologyMax Hospital,Saket, Delhi, India

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Preface to the Second Edition

The Color Doppler sonography has become an essential and integral armamentarium for the Radiology Departmentin order to give correct and accurate diagnosis in almost every system of the human body particularly in assessingthe cerebral, abdominal and peripheral vasculature. The addition of relevant illustration and text has given a newdimension to this book. I am sure that the sincere effort made by the contributors will be further appreciated andcritically analyzed. The book will definitely be useful to radiologists, obstetricians and gynecologists, physiciansand residents.

Satish K Bhargava

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Preface to the First Edition

Color Doppler sonography has been in use for more than three decades now and has constantly evolved to itspresent status of being the minatory of the vascular laboratory. It has unparalled application in assessing cerebral,abdominal and peripheral vasculature. Color Doppler is now widely applicable in intravascular, and interventionalprocedures. This added a new dimension of its role in therapeutic radiology. Its role in differentiating benign versusmalignant lesions is increasing day-by-day. The extent and severity of the disease process and hemodynamic alterationcaused by it can be confidently estimated. In fact all sonographers, must now be familiar with Doppler imaging, asblood flow assessment is used virtually every time an ultrasound examination is carried out.

Color Doppler sonography is a combination of Doppler ultrasound and gray scale ultrasound to providesimultaneous realtime visualization of soft tissues structures and blood flow over the entire scan field. Interpretationof this information required a sound knowledge of the basic technical principles of color Doppler imaging and thepathophysiology involved in the disease process. This book is a sincere effort to provide a clear scenario of thefascinating world of color Doppler sonography. It deals with the basic fundamentals of color Doppler sonographyand its application in the specific body regions. The extensive text covered in this book itself portrays the burdenborne by this aspect of imaging. An attempt has been made to provide an update knowledge of the subject. Use ofcontrast medium in vascular ultrasonography has been highlighted in this book. A satisfactory number of illustrationshave been included in each chapter to provide an interesting insight into the subject.

This is the first Indian book on color Duplex sonography. I feel that this sincere effort will be critically analyzed,appreciated and appraised.

Satish K Bhargava

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I am grateful to my colleagues and friends who gave timely support and stood solidly behind me in our jointendeavor of bringing out this book which was required keeping in view of wide acceptability of ultrasound.My special heartfelt thanks are due to the sincere and hardworking staff of M/s Jaypee Brothers Medical Publishersparticularly Shri Jitendar P Vij (Chairman and Managing Director), Mr Tarun Duneja (Director-Publishing) andMrs Samina Khan. It is indeed the result of the hard work of the staff of the publisher and the contributors who havealways shown keen desire to work with `smiling faces and with polite voices as a result of which this book has seenthe light of the day.

Acknowledgments

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Contents

1. The Story of Doppler ................................................................................................................ 1

Satish K Bhargava, AK Srivastava

2. Basic Hemodynamics ................................................................................................................ 3

AK Srivastava, Satish K Bhargava

3. Doppler Principle and Instrumentation .................................................................................. 15

Satish K Bhargava, AK Srivastava, Sumeet Bhargava

4. Doppler Spectral Analysis ....................................................................................................... 25

Satish K Bhargava, AK Srivastava, Sumeet Bhargava

5. Color Flow Imaging ................................................................................................................. 34

AK Srivastava, Sumeet Bhargava, Satish K Bhargava

6. Contrast Agents in Ultrasound ................................................................................................ 42

Sumeet Bhargava, Satish K Bhargava, Suchi Bhatt

7. Cerebrovascular Doppler Sonography..................................................................................... 53

Satish K Bhargava, Gopesh Mehrotra, Rajul Rastogi

8. Transcranial Doppler Sonography ........................................................................................... 66

Vipul Gupta

9. Doppler in Liver ...................................................................................................................... 84

Suchi Bhatt, Poonam Narang, Sumeet Bhargava

10. Role of Color Doppler in Splenic Lesions ............................................................................... 105

Sumeet Bhargava, Suchi Bhatt, Poonam Narang, Satish K Bhargava

11. Color Doppler in Pancreas .................................................................................................... 108

Sumeet Bhargava, Suchi Bhatt, Poonam Narang, Satish K Bhargava

12. Role of Color Doppler in Urinary System ............................................................................... 111

Suchi Bhatt, Satish K Bhargava, Rajul Rastogi, Sumeet Bhargava

13. The Retroperitoneum and Great Vessels .............................................................................. 135

Sumeet Bhargava, GP Vashist, Suchi Bhatt, Satish K Bhargava

14. Current Role of High-resolution Ultrasonography and

Color Doppler in the Diagnosis of Scrotal Diseases ............................................................... 153

Bharat Parekh, Rajul Rastogi, Sumeet Bhargava

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15. Duplex Ultrasonography of Erectile Dysfunction .................................................................. 164

Sanjay Thulkar, Deep N Srivastava

16. Color Doppler of Small Parts ................................................................................................. 169

GP Vashisht, Lalendra Upreti, Satish K Bhargava, Rajul Rastogi, Sumeet Bhargava

17. Doppler Imaging of Peripheral Arteries ................................................................................ 184

Satish K Bhargava, Rajul Rastogi

18. Venous System ..................................................................................................................... 196

Satish K Bhargava, Rohini Gupta, Sumeet Bhargava

19. Intravascular Ultrasound—Newer Advances,

Current Applications and Future Directions .......................................................................... 206

Sanjiv Sharma, Gurpreet Gulati

20. Role of Color Flow and Doppler in Obstetrics,

Gynecology and Infertility .................................................................................................... 216

Narendra Malhotra, Jaideep Malhotra, Rajul Rastogi, Sumeet Bhargava

21. Gray Scale Ultrasonography and Color Doppler Study in Fracture Healing ............................ 250

OP Sharma

Index ........................................................................................................................................... 255

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Duplex Ultrasonography of

Erectile Dysfunction

Erectile dysfunction (ED) or impotence is defined as aninability to achieve rigidity of the penis, which is sufficientfor penetration. It is broadly classified into twocategories—organic and psychogenic. Vasculogenicimpotence is the most common cause of organicimpotence. Many patients with erectile dysfunction havecombination of both organic and psychogeniccomponents. Therefore, the term vasculogenic ED doesnot rule out the presence of underlying psychologicalfactors. It merely means that vascular factors arepredominant cause of ED. Vascular ED has two differentpossible mechanisms—obstruction in penile inflow tract,termed as arterial ED and the inability to trap theincoming blood at sufficient pressure in the cavernosa,termed as veno-occlusive ED.

Anatomy and Physiology of Penile Erection

Paired internal pudendal arteries give rise to commonpenile arteries on both sides. These divide into fourarteries, one each to spongiosa, cavernosa, proximalurethra and dorsum of the penis (deep dorsal artery).The cavernosal artery provides blood to cavernosa viamultiple helicine arteries that open directly into thecavernosal sinusoids. Venules located within thesubintimal space between the periphery of erectile tissueand the tunica albuginea provides venous outflowchannel from corpora cavernosa via peripheral lacunae.

Penile erection is a neurovascular phenomena inwhich the neurological stimulus via parasympatheticnerves from sacral 2,3,4 leads to smooth muscle relaxationin helicine arteries leading to vasodilatation. There is alsorelaxation of trabecular smooth muscle relaxation incavernosa, which coupled with increased blood flowleads to increase in size and length of the penis causingtumescence. In the next phase, subtunical venules arecompressed against tunica albuginea due to dilatation ofsinusoids and increase in intracavernosal pressure,leading to erectile response. If this veno-occlusivemechanism is competent, the arterial inflow leads toincrease in intracavernosal pressure to the level of meanarterial pressure. Perineal muscles contractions generateto further increase in pressure and erectile response leadsto the rigidity.

Evaluation of Erectile Dysfunction

Various tests available for evaluation of vascular EDincludes papaverine induced penile erection (PIPE) test,pharmacopenile Duplex ultrasonography (PPDU),cavernosometry with cavernosography, penile angio-graphy and radionuclide imaging. PPDU is sufficient formajority of patients, other more invasive tests arereserved for patients actually considered for surgicaltreatment.

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Traditionally, evaluation of ED begins withPIPE test in which the erectile response of thepenis is studied after intracavernosal injection ofpapaverine or some other vasoactive agent.Normal erectile response is suggestive of normalvascular status and hence neurological orpsychological factors are considered as apredominant cause. If only partial or short-livederection is resulted, then the vascular ED ispresumed.

Pharmacopenile Duplex Ultrasonography

(PPDU)

PPDU is fast becoming the first line investigationto define vascular ED and to differentiatebetween arterial insufficiency and incompetentveno-occlusive mechanism.

The different vasoactive agents used forPPDU are papaverine, prostaglandin (PGE1) andcombination of papaverine and phentolamine.Papaverine may lead to false negative erectileresponse in some patients or may lead topersistent painful erection (priapism) in others.Prostaglandin (PGE1) has better erection rate andlesser incidence of priapism.1 Genital self-stimulation, visual erotic stimulation orapplication of light tourniquet at penoscrotaljunction may augment the erectile response tothese agents.

Technique

The examination must be carried out in anatmosphere of privacy. Anxiety and resultantsympathetic stimulation may interfere with theresponse to pharmacological stimulus, henceevery effort should be made to relax the patientduring the procedure. A rubber band ispreferably placed at the root of the penis. Thesonographic evaluation begins with scanning ofthe flaccid penis in transverse plane to measurethe diameter of the cavernosal arteries. Then,under aseptic precautions, intracavernosalinjection of 60 mg of papaverine is made with26/27 G needle in either of the cavernosa.Injection on the contralateral side is not requiredas cross communications exist between both

sides. Care must be taken not to inject insubcutaneous tissue, vessels or urethra. Erectileresponse is graded visually from E0 to E5 asdescribed by Broderick.2 E0 refers to no response,E1 to partial elongation of the shaft only, E2 tomoderate tumescence without any rigidity. E3erection achieves full tumescence but there is norigidity and the penis is easily bendable. E4 andE5 grades show full erection with partial rigidityor full rigidity for at least 20 minutes respectively.After evaluating the erectile response, scanningis started from root of the penis to the distal part;both in transverse and longitudinal plane. Dorsalscanning in longitudinal plane is necessary toidentify penile deformities and cavernosalcollaterals. Post-injection diameters of bothcavernosal arteries are measured in transverseplane. Angle corrected flow velocities aremeasured in cavernosal arteries as proximal aspossible (Fig. 15.1). Initial flow velocities aretaken five minutes after the injection. Themeasurements are repeated after short intervalstill peak rigidity. Most accurate flowmetry valuescoincide with peak rigidity of the penis. If norigidity is achieved initially, the flowmetry maybe obtained at least till 15 minutes beforetermination of the examination, as someindividuals may reach to that stage after sometime.

Figure 15.1: PPDU examination shows technique for placement ofsample volume in the cavernosal artery with angle correction

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Post-papaverine injection normal spectralwaveform cavernosal artery normally has fivereproducible phases3 (Fig. 15.2). In phase 1, thereis increase in both systolic and diastolic velocities.In phase 2, there is progressive decrease in enddiastolic velocity and appearance of the dicroticnotch. Patients with severe venous leakage donot progress beyond phase 2. In phase 3 diastolicflow approximates zero and it is reversed inphase 4. Phase 5 is characterized by eventual lossof both systolic and diastolic flow signals.Various parameters and their accepted normalvalues studied on flowmetry are maximumrecorded peak systolic velocity (PSV) of 30 cm/second or more, minimum end diastolic velocity(EDV) of 5 cm/second or less (zero or reverseddiastolic flow included as normal), accelerationtime (AT) of 0.11 second or less, and resistiveindex (RI) of 0.85 or more. Mild variations areseen in cut off values as described in variousreported studies.

The studies that have been publishedregarding the normal Doppler flowmetry valueshave been on small number of healthyvolunteers.3,4 There has been no such study onIndian patients. At our institution, we could notconduct our study on normal healthy volunteersbecause of invasive nature of the procedure andfeasibility and ethical considerations. Therefore,it was decided to study patients with psycho-

genic impotence with a normal erection elicitedon pharmacological stimulus test since thesepatients can be presumed to have a normalvascular status.5,6

In our study comprising 30 men, the meanage was 24.8 years. This is significantly less thanthe mean age of patients in the earlier studies byValji et al and Quam et al who reported the meanage of 51 and 56 years respectively in theirstudies.7,8 This lower mean age of patients in ourpopulation is difficult to explain but probably itis related to observation of our clinicalpsychologist that elderly men are usually hesitantto seek medical advice for their sexual problems(personal communication). They also have atendency to regard it as part of aging rather thana disease problem. All 30 men in our study werediagnosed to have nonvasculogenic ED. Theiryounger mean age emphasize the fact that theyounger men have less incidence of organicimpotence than older men as the later group arelikely to suffer from atherosclerosis and areplacement of elastic collagen with non-distensible collagen leading to vasculogenicerectile dysfunction.9 All the patients had peaksystolic velocity above 35 cm/sec, whichcorrelates well with that reported by Benson etal.10 However, mean PSV was 61.3 cm/secondwhich is significantly higher than all previouslyreported studies.3,8 Analysis of PSV variationwith age has shown that there is a negativecorrelation and thus a higher mean PSV in thepresent study can be attributed to younger ageof the study population. Similar results have beenreported by Chung WS et al.11 The meanacceleration time, which is now considered thebest discriminator of arterial impotence, was 0.06sec and none of the patients had AT of more 0.1sec which is in conformity with existingliterature.

The mean end diastolic velocity was–1.2 cm/seconds (negative sign indicates flow reversal)and it also correlates well with the prevailingconsensus in literature.3 Mean RI was 0.93 inwhom diastolic flow reversal was not achieved.Majority of the patients had either absent orreversed diastolic flow (20 patients) or EDV 5

Figure 15.2: Serial spectral tracings during PPDU shows various phasesof flow pattern (refer text)

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cm/sec or less (six patients). Four patients hadend diastolic velocity more than 5 cm/sec,however, these patients had a very high PSVsand normal resistive indices. They also showednormal rigid erection on pharmacologicalstimulation. Thus, it appears that EDV > 5 cm/sec alone may not be a specific indicator of veno-occlusive insufficiency and it should becorrelated with resistive index for diagnosis ofveno-occlusive insufficiency. Normal mean PSVis dependant upon the age of the individual andit decreases with advancing age.12

In summary, abnormal PSV and AT aresuggestive of arterial cause while abnormal EDVand RI indicate venous leakage. RI is consideredmore accurate than EDV for assessment ofvenous competence as probe vessel angle, themost important variable associated with theprocess of sampling and velocity calculation isfiltered out in calculation of RI. Any increase incavernosal artery diameter by less than three-fourth of the baseline is also suggestive of arterialinsufficiency. If arterial disease is present,intracavernosal pressure remains below systemicpressure and veno-occlusion cannot occur, evenif this mechanism is intact, and diastolic flow willcontinue to persist. Therefore, veno-occlusivemechanism cannot be assessed in presence ofarterial disease.

Treatment of Complications

The most common complications during thediagnostic work-up and especially during thePPDU, is a papaverine induced prolonged,painful erection or priapism. Not all of themrequire specific treatment as penile detume-scence generally occurs within few hours. In casethe duration of erection exceeds six hours, thecorpora cavernosa are drained to decrease thepressure and 10 microgram of adrenaline isinjected intracavernosally to induce cavernosalsmooth muscle contraction, effective venousdrainage and restriction of arterial flow. Theadrenaline of 1 in 1000 strength can be dilutedwith appropriate amount of normal saline toproduce adrenaline injection of the desiredstrength. Compression bandage is also applied

for few minutes. In case the erection has recurred,the procedure can be repeated.

Peyronie’s Disease

This is a benign condition resulting from inelasticscar of tunica albuginea, which producecurvature deformities of penis and ED. Onsonography, the penile plaques are seen asechogenic focal thickening of tunica albugineawhich may displace or encase cavernousvasculature. Dense plaques may containcalcification and produce acoustic shadowing(Fig. 15.3) however, calcification can be seen evenwithout evidence of calcification on the plainradiographs. Most plaques are located on thedorsal surface of middle third of the shaft of thepenis.

Vasculogenic impotence is most common cause of

organic impotence.

PPDU differentiates arterial insufficiency and

incompetent veno-occlusion.

Abnormal peak systolic velocity and acceleration time

suggest arterial cause.

Abnormal end-diastolic volume and resistive index

indicate venous leakage.

Veno-occlusion cannot be assessed in presence of

arterial insufficiency.

KEY POINTS

Figure 15.3: Peyronie’s disease: dense echogenic plaque of tunica withdistal shadowing is seen on the dorsal surface of the penis

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REFERENCES

1. Meuleman, Diemont WL. Investigation of erectiledysfunction. Urol Clin N Am 1995;22:803-19.

2. Broderick GA, Arger P. Duplex Dopplerultrasonography: noninvasive assessment ofpenis anatomy and function. Semin roentgeno-logy 1993;28:43-56.

3. Shwartz AM, Lawe M, Berger RE et al.Assessment of normal and abnormal erectilefunction–colour Doppler sonography versusconventional techniques. Radiology1991;180:105-09.

4. Shabsigh R, Fishman IR, Quesda ET et al.Evaluation of vasculogenic erectile impotenceusing penile duplex sonography. J Urol1990;142:1469-74.

5. Lue TF, Tanagho EZ. Physiology of erection andpharmacological management of impotence. JUrol 1987;137:829-35.

6. Merckx LA, DeBruyne RMG, Goes E et al. Thevalue of dynamic colour Doppler scanning in thediagnosis of venogenic impotence. J Urol1992;148:318-20.

7. Valji K, Bookstein JJ. Diagnosis of arteriogenicimpotence: Efficacy of Duplex sonography as a

screening tool. AJR Am J Roentgenology1993;160:65-69.

8. Quam JP, King BF, James EM et al. Duplex andcolour Doppler sonographic evaluation ofvasculogenic impotence. AJR Am J Roentgeno-logy 1989;153:1141.

9. Padma Nathan H, Boyd SD, Chung D. Thebiochemical effect of ageing, diabetes andischemia on corporal and tunical collagen. J Urol1991;145:342-518.

10. Benson CB, Aruny JE, Vickers MA. Correlationof Duplex sonography with angiography in-patients with erectile dysfunction. AJR Am JRoentgenology 1993;160:71-73.

11. Chung WS, Park YY, Kwon SW. The impact ofaging on penile hemodynamics in normalresponders to pharmacological injection:Doppler sonographic study. J Urol 1989;157:2129-31.

12. Bhargava R, Srivastava DN, Thulkar S et al.Colour Duplex Doppler ultrasonographyevaluation of non-vasculogenic male erectiledysfunction: an Indian perspective. Australian,Radiology 2002 (in press).