FUNCTIONALVASCULARIMAGINGOFATHLETES

RichardL.Hallett,MDChief,CardiovascularImagingNorthwestRadiologyNetworkIndianapolis,INClinicalAssistantProfessor–RadiologyStanfordUniversityStanford,CA

RC412C 1December2015 S504AB 16:30

xraydoc97@yahoo.com

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LearningObjectives

§  Identifyanatomicandfunctionallesionsthatpredisposetovascularentrapmentandfibroticsyndromesinathletes.

§  Describemethodstoassessvascularentrapmentandfibroticsyndromesusingdynamic,functionallychallengedCTAandMRA.

§  Describetheimagingfindingsfordiagnosis.

Whatisyourexperiencewithfunctional(dynamic)cardiovascularimaging?

A.  None B.  A little- once or twice C.  We perform these exams occasionally D.  Extensive experience E.  I do not know what functional imaging means

VascularDiseasesinAthletes

•  UpperExtremity– ThoracicOutletSyndrome(TOS)

•  Pelvis–  IliacEndofibrosis

•  LowerExtremity– PoplitealEntrapmentSyndrome(PAES)

Background…….

§  Vasculardiseasesareeasilyoverlookedinathletes

§  ThoroughvascularH&Pneeded§ DecidingWHEN(orIF)toimagevascularentrapmentsyndromesrequiresclinicaljudgmentandmulti-specialtycoordination!!

DYNAMICEVALUATIONISIMPORTANT!!

DynamicCross-SectionalImaging

•  Principle:simulatethepredisposingmoCon/posiConandassessvascularresponse•  �Stress�and�Relaxed�Imaging•  VaryCmingtoassessarteries/veins

•  ThoracicOutletSyndrome(TOS)

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Themostcommonanatomiclocationforvascularthoracicoutletsyndromeis

A.  Costo-clavicular space B.  Retro-pectoralis minor space C.  Interscalene Triangle D.  Coraco-clavicular space

Linda D D et al. Radiographics 2010;30:1373-1400

ThoracicOutletSyndrome(TOS)

•  SymptomaCccompression/entrapmentofneurovascularstructuresbyboneand/orsoHCssueastheypassthroughthecervicoaxillarycanal

•  90%Neurogenic(PT,posturalTx,NSAIDs)•  10%Vascular

•  Venous>Arterial

Linda D D et al. Radiographics 2010;30:1373-1400

ComponentsofCervico-AxillaryCanal

§  InterscaleneTriangle:#1siteofcompression

§  CostoclavicularSpace:#1siteforvascularTOS

§  Retro-pectoralisminorspace:#1siteformasses

Themostcommonanatomiclocationforvascularthoracicoutletsyndromeis

A.  Costo-clavicular space B.  Retro-pectoralis minor space C.  Interscalene Triangle D.  Coraco-clavicular space

CORRECT ANSWER

Linda D D et al. Radiographics 2010;30:1373-1400

CTAforTOS:ComboDirect/IndirectCTA

§  IpsilateralIV,armoverheadw/palmtapedup§  Bolus:120mLfull-strength@4ml/s§  Chase:100mLdilute(10%)contrast@2.5ml/s

•  Caninjectcontralateralarmatsametime(dilute)

§  65secempiricdelay,scancaudo-cranial§  Armdown,immediatere-scancranio-caudal§  VolumetricReview

BilateralDirect/IndirectCTA

VenousTOS:�EffortThrombosis�

§  Paget-Schroettersyndrome(PSS)§ AKAaxillo-subclavianvenousthrombosis

§  �Overhead�athletes§  PEinupto1/3!!*§  Post-thromboticsyndrome(later)

*PerlowskiAA.VascMed(2010)vol.15(6)pp.469-79

EffortThrombosis:36YOweightlifter

Post-Op1stribresection

ArterialTOS§  �Overheadathletes�§  SX:Coolness,weakness,diffusearm

pain(ischemicneuritis)§  Cause:Repetitivecompressioninjury

ú  Anatomicpredisposition(tightCCS)ú  Post-traumatic,bonycallusú  Scalenehypertrophy

ArterialandVenousTOS:16YOVolleyballAthlete

RESTSTRESS

MRAforTOS:BloodPoolMRA

§  Anatomicimaging:ObliquesagandcorT1/T2

§  RelaxedandChallengedimaging:§  Gadofosveset(bloodpoolagent)§  Breath-holdFSPGR,ECG-gated,highresolution(1.8mmST,448x448matrix)CORONALacquisition§ Challenged:ArmAbducted§ Relaxed:ArmDown

Arm UP Arm DOWN

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IliacEndofibrosis

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Iliacendofibrosisisa(n):

A.  Acute inflammatory vasculopathy B.  Early (accelerated) atherosclerotic process C.  Vasculitis related to HLA-B27 antibodies D.  Non-inflammatory, non-atherosclerotic disease

LimCS,etal.EurJVascEndovascSurg2009:38:180-6.

FlowlimitationsintheAthlete’spelvis

§  Dynamic:ú  Elongated/tortuousvesselsú  Kinkingwithorw/ostenosis(elongation/tethering)

ú  compression(psoashypertrophy,ligaments)

§  Static:IliacendofibrosisLimCS,etal.,EurJVascEndovascSurg2009:38:180-6.

§  90%ofptsarecyclists•  >10,000km/yror150,000kmlifetime•  Also:speedskaters,runners,wtlifters,

XCskiers,andrugbyplayers§  90%externaliliacartery§  Smooth,eccentric,non-calcified•  Pathology:intimalfibroplasia,medial

hypertrophy,andadventitialhyperplasia.Involvedsegmentsuniversallyfreefromatherosclerosis.

LimCS,etal.EurJVascEndovascSurg2009:38:180-6.

Iliacendofibrosisisa(n):

A.  Acute inflammatory vasculopathy B.  Early (accelerated) atherosclerotic process C.  Vasculitis related to HLA-B27 antibodies D.  Non-inflammatory, non-atherosclerotic disease ANSWER

LimCS,etal.EurJVascEndovascSurg2009:38:180-6.

EndofibrosisCTA:Imagingtechnique

§  Twophases:relaxationandhipflexion§  Coverage~40cm§  Relaxation–100kVp,flexion–120kVp§  ~80mLofIVcontrastat4-5mL/sforeach

phase(20secinjection)§  Salineflushatsamerate§  Scantime10-12sec§  VolumetricReview

CTA:Positioning§  Simulatecyclingpositionascloselyaspossible

consideringspacewithinCTgantry(almost900)

Case1

§  45yoavidcyclist§  Proximalthighpain,crampingwithexertion

§  ABIdropswithexertion

Supine,legsextended

HipflexionDynamicFlowRestricCon

Case2

§  26yoelitefemalecyclist

§  leftthighandbuttockpainathighperformancelevels.

Case2NEUTRAL FLEXION

Case3

§  49yoavidcyclistx30yrs§  leftthighandbuttockpainathighperformancelevels.

§  Paindescribedasa�deepburn�§  ABIR/L:1.3/1.2§  ExerciseABIR/L:1.5/1.2

CTAatRest

•  Pathology:inCmalthickeningandfibrosis•  Noinflammatorychange

EndofibrosisMRA:Imagingtechnique

§  Anatomicimaging–T1/T2§  ArterialPhaseFSPGRMRA(bolustrack)§  RelaxedandHipFlexionimaging–

§  Respiratorygated,steadystateacquisition§  Near-Isotropic§  BloodPoolcontrastAgent(Gadofosveset)

§  VolumetricReview

Naehle CP. J Am Coll Cardiol Img. 3 2010:504-513

VascularDiseasesinAthletes

• LowerExtremityPoplitealEntrapmentSyndrome(PAES)

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MostcasesofPoplitealentrapmentsyndromearisefrom:

A.  Chronic repetitive trauma to popliteal artery / vein B.  Embryologic conflict between muscles and vessels C.  Premature atherosclerotic disease D.  Chronic exertional compartment syndrome

Macedo TA, et al. Popliteal Artery Entrapment Syndrome: Role of Imaging in the Diagnosis. American Journal of Roentgenology. 2003 Nov;181(5):1259–65.

PoplitealSpace-Embryology

§  Inutero:competitionbetweenpoplitealneurovascularbundleandmigratingmuscles(medialheadgastrocnemius)forspace

§  IfdelayedorabnormalmigrationàMHGtoofarlateral

ú  spaceislimited

CausesofPoplitealEntrapment

§ AnatomicCompression• Abnormalpoplitealarterycourse• Abnormalmuscle(MHG)

•  Both§ �Functional�compression

MostcasesofPoplitealentrapmentsyndromearisefrom:

A.  Chronic repetitive trauma to popliteal artery / vein B.  Embryologic conflict between muscles and vessels C.  Premature atherosclerotic disease D.  Chronic exertional compartment syndrome

ANSWER

Macedo TA, et al. Popliteal Artery Entrapment Syndrome: Role of Imaging in the Diagnosis. American Journal of Roentgenology. 2003 Nov;181(5):1259–65.

ClassificationofPAESType Anatomy

I PA travels aberrantly, medial to normally positioned MHG

II Anomalous lateral and inferior origin of MHG, PA displaced medially

III Normal PA compressed by muscular slip or aberrant band from MHG

IV PA deep in popliteal fossa, entrapment from aberrant band or popliteus muscle

V Any type of entrapment involving popliteal vein

VI �Functional� Entrapment

*WhelanTJ.In:HaimoviciH,Ed.Vascularsurgery:principlesandtechniques.NewYork:McGraw-Hill,1984:557-67

§  Youngerpopulation,highlyconditionedathletes§  Neurovascularcompressionbyhypertrophicgastrocnemius+/-solealsling

§  Longersegmentinvolvement(vs.anatomicPAES)

§  ConservativeTxfirst,debulkingifneeded

FunctionalPoplitealEntrapment(TypeVI)

§  3phases–relaxed,activeplantarflexion,venous•  Activeplantar-flexionwithoutbearingdown(straps)

§  ~80mLofcontrast(4mL/s)for2phasesfollowedbysalineflushatsamerate

§  BolustrackdistalSFA§  Scantime:12-15secon64-MDCT§  Pulseoximeteronsymptomaticlargetoe

PAES:CTAImagingTechnique

Soccer Player - Type I PAES

TypeIIIPAES-ThrombosisofleHpoplitealartery

prov

ocation

Relax

ed–po

steriorv

iew

LEFT RIGHT

FuncConal(TypeVI)PAES

prov

ocation

relaxe

d

PAES:ChallengedMRAtechnique

§  Anatomicimaging(axial/coronalT1/T2)

§  ChallengedandRelaxedAcquisition(likeCTA)

§  bloodpoolagentgadofosveset§  Thin-sliceCoronal(1.4mm)steady-

stateacquisition(576x576matrix)§  3Dassessment

STRESS

PAES:ChallengedMRAtechnique

Conclusions§  Vasculardiseasesinathletescanbeasignificantsourceofdisabilityandperformanceloss

§  Functionalimagingisimportantforaccuratedetectionandcharacterizationofvascularentrapment/stenoticsyndromes

§  CTAandMRAwithfunctionaltechniquesallownon-invasiveassessment

ThanksforYourABenCon!!

www.stanford.edu/~hallett Choose folder “RSNA 2015”

Special Thanks to: Dominik Fleischmann, MD Deirdre Sheahan, MD Kevin Sheridan, MD Joel Feldman, MD

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