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Lungemboli och CTLungemboli och CT

Var stVar ståår vi r vi idag?idag?Ulf Nyman, docentUlf Nyman, docent

Institutionen fInstitutionen föör r translationelltranslationell medicinmedicin

Divisionen fDivisionen föör medicinsk radiologir medicinsk radiologi

SkSkåånes universitetssjukhus, Malmnes universitetssjukhus, Malmöö

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•• Stefan RosforsStefan Rosfors•• klinisk fysiolog, Sklinisk fysiolog, Söödersjukhuset, Stockholmdersjukhuset, Stockholm

•• Klas Klas MMåårere•• radiolog, Universitetssjukhuset, Linkradiolog, Universitetssjukhuset, Linkööpingping

•• Ulf NymanUlf Nyman•• radiolog, Lasarettet i Trelleborgradiolog, Lasarettet i Trelleborg

•• Margareta Margareta HellgrenHellgren--WWåångdahlngdahl•• gynekolog, SU/gynekolog, SU/ÖÖstra Sjukhuset, Gstra Sjukhuset, Gööteborg.teborg.

SBU-report 158/2002Blodpropp Blodpropp –– fföörebyggande, diagnostik och rebyggande, diagnostik och behandling av venbehandling av venöös s tromboembolismtromboembolism

DiagnostikDiagnostik

• Stefan Rosfors• klinisk fysiolog, Södersjukhuset, Stockholm

• Klas Måre• radiolog, Universitetssjukhuset, Linköping

• Ulf Nyman• radiolog, Lasarettet Trelleborg

• Margareta Hellgren-Wångdahl• gynekolog, SU/Östra Sjukhuset, Göteborg.

SoS:s arbetsgrupp SoS:s arbetsgrupp –– VVåård av blodpropprd av blodpropp

•• David BergqvistDavid Bergqvist kkäärlkirurgirlkirurgi

•• Mats EliassonMats Eliasson internmedicininternmedicin

•• Bengt ErikssonBengt Eriksson ortopediortopedi

•• Henry ErikssonHenry Eriksson internmedicininternmedicin

•• Margareta HellgrenMargareta Hellgren--WWåångdahl ngdahl gyn/obstetrikgyn/obstetrik

•• KarlKarl--GGöösta Ljungstrsta Ljungströömm kirurgikirurgi

•• Ulf NymanUlf Nyman radiologiradiologi

•• Sam SchulmanSam Schulman hematologihematologi

www.socialstyrelsen.se/riktlinjer

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Googla Koagulationscentrum Region Skåne

US = UltrasonographyScintigraphy

CT = computed tomography

DD--dimerdimer

Clinical probability

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KliniskKlinisk osannolikosannolik PE & PE & negativnegativ DD--dimerdimer

3 3 mmåånadersnaders uppfuppfööljningljning fföörr VTEVTE

•• AntalAntal ((metaanalysmetaanalys)) 10 94110 941

•• PE PE frekvensfrekvens 21%21%

•• KliniskKlinisk osannolikosannolik & & negneg DD--dimerdimer 27% (2227% (22--34)34)

•• FalsktFalskt negativanegativa (95% KI)(95% KI) 0.4% (0.20.4% (0.2--0.7) 0.7)

LucassenLucassen MetaMeta--analysis Ann Intern Med 2011;155:448analysis Ann Intern Med 2011;155:448--60.60.

BayesBayes’’ theoremtheorem

•• Thomas Bayes (1702Thomas Bayes (1702--1761)1761)

•• English clergyman/mathematicianEnglish clergyman/mathematician•• Fellow of Royal SocietyFellow of Royal Society

•• ””Essays towards solving a probaEssays towards solving a proba--

bility in the doctrine of chancesbility in the doctrine of chances””•• Found after his death and published 1763Found after his death and published 1763

Taube & Malmquist. Räkna med vad du tror. Bayes’ sats i diagnostiken. Läkartidningen 2001;98(24):2910-2913.Barnard Biometrika 1958;45(parts 3&4):293-315

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BayesBayes’’ theoremtheorem

PIOPED II PIOPED II (NEJM 2006;345:2317(NEJM 2006;345:2317--27)27)

Prospective Prospective multicentermulticenter investigation in USAinvestigation in USA

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CT for CT for acuteacute pulmonarypulmonary embolismembolism

SensSens SpecSpec

••PIOPEDPIOPED--IIII 83%83% 96%96%

•• 84% 484% 4--row row detectordetector

•• 16% 816% 8--1616--row row detectordetector

Stein et al. New Eng J Med 2006;354;2317-27.

Negative Negative computedcomputed tomographytomography

””LowLow”” sensitivitysensitivity

•• Bilateral ultrasound on all negative CT (80%)Bilateral ultrasound on all negative CT (80%)

•• FedulloFedullo & & TapsonTapson NEJM 2003;349:1247NEJM 2003;349:1247--5656

•• RoutineRoutine CT CT venographyvenography (100%)(100%)

•• Cham et al. Radiology 2005;234:591Cham et al. Radiology 2005;234:591--594594

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5

19

66

6

23

54

0

20

40

60

80

Låg Måttlig Hög

DVTLE

Percentage 48 35 17

DVT (20%) LE (17%)11 studies 4 studiesn: 3034 n: 2840

J Thromb Haemost 2003;1:1888

Wells Wells clinicalclinical criteriacriteria of DVT and PEof DVT and PE

VTE%

LowLow ModerateModerate HighHigh

BayesBayes’’ teoremteorem

Prevalens (%): 30

Test Ja Nej Pos PPV (%)

Neg NPV (%)

Sens (%) Spec (%)

Sjukdom

1000900100

88186417

1193683

9683

70

98

10

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BayesBayes’’ teoremteorem

PIOPED II PIOPED II (NEJM 2006;345:2317(NEJM 2006;345:2317--27)27)

Clinicians (and radiologists) should Clinicians (and radiologists) should

probably think twice before accepting a probably think twice before accepting a

PE diagnosis in a patient in whom the PE diagnosis in a patient in whom the

disease is thought to be clinically unlikely disease is thought to be clinically unlikely

””unless CTA is undisputedly positiveunless CTA is undisputedly positive””

Perrier & Bounameaux. Letter to the Editor JAMA 2006;345:2383-4

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BayesBayes’’ teoremteorem

Prevalens (%): 30

Test Ja Nej Pos PPV (%)

Neg NPV (%)

Sens (%) Spec (%)

Sjukdom

1000500500

56548085

43520415

9683

95

85

50

BayesBayes’’ teoremteorem

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Management studyManagement study

•• Patients w. negative CT are not Patients w. negative CT are not anticoagulatedanticoagulated

•• apart from other indications than VTEapart from other indications than VTE

•• Clinical followClinical follow--up for 3 monthsup for 3 months

•• Objective testing in case of DVT/PE symptomsObjective testing in case of DVT/PE symptoms

•• VTE VTE ≤≤1.5% (upper 95% CI <3%) acceptable 1.5% (upper 95% CI <3%) acceptable

Negative CT Negative CT -- Outcome studiesOutcome studiesPos DPos D--dimerdimer or high or high clinclin prob/clinprob/clin likely PElikely PE

AuthorAuthor YearYear NN VTE VTE (3mo (3mo f/uf/u))

FrequencyFrequency Upper 95% CIUpper 95% CI

•• van van StrijenStrijen 20032003 510510 0.8%0.8% 1.6% 1.6%

•• PerrierPerrier 20052005 524524 1.7%1.7% 2.8%2.8%

•• GhanimaGhanima 20052005 329329 0.9%0.9% 1.9%1.9%

•• van Bellevan Belle 20062006 22492249 1.3%1.3% 1.8%1.8%

•• AndersenAndersen 20072007 694694 0.4%0.4% 0.9%0.9%

•• RighiniRighini 20082008 558558 0.9%0.9% 1.7%1.7%

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Konklusion

•• CT missar smCT missar småå LE som inte tycks LE som inte tycks

krkrääva behandlingva behandling

•• Ingen indikation fIngen indikation föör rutinmr rutinmäässig ssig

venundersvenundersöökningkning vid negativ CT vid negativ CT

•• Huvudsakliga problemet med CT Huvudsakliga problemet med CT

äär r ööverdiagnostik verdiagnostik

Isolated Isolated subsegmentalsubsegmental (ISS) PE(ISS) PE

•• MultiMulti--slice CT allows better visualization of slice CT allows better visualization of

subsegmentalsubsegmental arteries, hence the rate of arteries, hence the rate of

isolated isolated subsegmentalsubsegmental PE may increasePE may increase

•• It is unclear whether the riskIt is unclear whether the risk--benefit ratio of benefit ratio of

anticoagulant therapy is favorableanticoagulant therapy is favorable

Carrier et al. J of Thrombosis & Haemostasis 2010;8:1716-22

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Rate of isolated subsegm PERate of isolated subsegm PESystematic review & metaSystematic review & meta--analysesanalyses

SingleSingle--slice (n=15)slice (n=15) MultiMulti--slice (n=11)slice (n=11)

Carrier et al. J of Thrombosis & Haemostasis 2010;8:1716-22

Rate of isolated Rate of isolated subsegmsubsegm PEPE

Systematic review & metaSystematic review & meta--analysesanalyses

SingleSingle--slice (n=15)slice (n=15) MultiMulti--slice (n=11)slice (n=11)

33--5 mm slices5 mm slices 11--2 mm slices2 mm slices

4.7%4.7% 9.4%9.4%

44--det: 7.1%det: 7.1%

1616--det: 6.9%det: 6.9%

64 64 detdet: 15%: 15%

Carrier et al. J of Thrombosis & Haemostasis 2010;8:1716-22

Higher rate of VTEHigher rate of VTE

during during f/uf/u of of negneg CTCT

due to FN diagnosis?due to FN diagnosis?

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Rate of isolated subsegm PERate of isolated subsegm PE

Systematic review & metaSystematic review & meta--analysesanalysesSingleSingle--slice (n=15)slice (n=15) MultiMulti--slice (n=11)slice (n=11)

3 months VTE risk after negative CT3 months VTE risk after negative CT

0.9%0.9% 1.1%1.1%

44--det: 1.4%det: 1.4%

1616--det: 0.6%det: 0.6%

64 det: 0.8%64 det: 0.8%

Carrier et al. J of Thrombosis & Haemostasis 2010;8:1716-22

Rate of isolated Rate of isolated subsegmsubsegm PEPE

MultiMulti--slice CT increases the rate of slice CT increases the rate of subsegmsubsegm PE PE

w/o lowering the 3 w/o lowering the 3 mosmos risk of VTE of negative CT risk of VTE of negative CT

suggesting that they are not clinically relevantsuggesting that they are not clinically relevant

Carrier et al. J of Thrombosis & Haemostasis 2010;8:1716-22

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Rate of Rate of subsegmentalsubsegmental PEPE

SubsegmentalSubsegmental PE most prevalent in lowPE most prevalent in low--

probability V/Q scan (PIOPED)probability V/Q scan (PIOPED)

Patients w. low/intermediate V/Q and Patients w. low/intermediate V/Q and

negative serial proximal US can be safely negative serial proximal US can be safely

left without anticoagulation left without anticoagulation

Carrier et al. J of Thrombosis & Haemostasis 2010;8:1716-22

Isolated Isolated subsegmentalsubsegmental PEPE

•• Reported isolated Reported isolated subsegmentalsubsegmental PE should be PE should be

reviewed by an reviewed by an experiencedexperienced radiologistradiologist

•• Poor Poor interobserverinterobserver agreementagreement

•• If isolated If isolated subsegmentalsubsegmental, consider serial , consider serial

proximal US, especially if at risk for ACproximal US, especially if at risk for AC

•• Prospective management study underwayProspective management study underway

•• No AC if normal bilateral serial proximal USNo AC if normal bilateral serial proximal US

•• France, Switzerland and CanadaFrance, Switzerland and Canada

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V/Q mismatchV/Q mismatch

DifferentialdiagnoserDifferentialdiagnoser

SBUSBU--rapport 158rapport 158--II/2002II/2002

Kapitel 3.6 Skintigrafi, sid 130Kapitel 3.6 Skintigrafi, sid 130

Pulmonary embolism?Pulmonary embolism?

•• Man, 44 years, arabic originMan, 44 years, arabic origin

•• Hodgkin lymphomaHodgkin lymphoma

•• HighHigh--quality CT Mayquality CT May--Oct 2009 neg for PEOct 2009 neg for PE

•• 370 HU, no artefacts370 HU, no artefacts

•• peripheral vessels well depictedperipheral vessels well depicted

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Lungembolism?Lungembolism?

VentilationVentilation

PerfusionPerfusion

VentilationVentilation

PerfusionPerfusion

Anterior Posterior

Planar V/QPlanar V/Q

SPECTSPECT

Extensive PEExtensive PE

despite normal despite normal

high quality CT:shigh quality CT:s

??????????

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Anatomisk obstruktionsgradAnatomisk obstruktionsgrad

1. BNP (brain natriuretic peptide), computed tomography or echocardiography.2. Cardiac troponin, T or I-positivea) In case of chock/hypotensionthere is no need to evaluate the right ventricleEuropean Society of Radiology guidelines (www.escardio.org/guidelines)

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Risk stratificationRisk stratification

•• Anatomical obstruction scoreAnatomical obstruction score

•• Right ventricular dysfunctionRight ventricular dysfunction

•• dilatation RV (dilatation RV (load) secondary to load) secondary to pulmonary resistancepulmonary resistance

•• inflow to left heartinflow to left heart, reduced left ventricle, reduced left ventricle

•• coronary insufficiency, right ventricular failure coronary insufficiency, right ventricular failure

•• initially increased pulmonary artery pressure now fallsinitially increased pulmonary artery pressure now falls

RV/LV ratio 2:1<1 normal

>1.5 warning!

65% obstruction index

Septum

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RenalRenal impairmentimpairment

•• DosesDoses decreasesdecreases with with increasedincreased detectordetector rowsrows

•• DoseDose per kg per kg bodybody weightweight

•• 120 kVp 120 kVp 80 kVp80 kVp

•• increasedincreased iodineiodine attenuation*1.6attenuation*1.6

•• DecreasedDecreased cardiac outputcardiac output•• high high ageage + + renalrenal impairmentimpairment cardiac cardiac diseasedisease

•• HalvedHalved CM CM dosedose –– 300 300 150 mg I/kg150 mg I/kg

•• IncreasedIncreased tubetube loadingloading (mAs)*4(mAs)*4•• to to keepkeep image image noisenoise constantconstant, , radiationradiation increasedincreased by 50%by 50%

Acta Radiol 2009;50:181Acta Radiol 2009;50:181--193193

Eur Radiol 2010;20:1321Eur Radiol 2010;20:1321--30.30.

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1616--channel MDCT for PEchannel MDCT for PE

Bae et al. Radiology 2005;236:677-684 (120 ml 350 mg I/ml, 3-4 ml/s; 30-40 sec)

200 mg I/kg200 mg I/kg

150 mg I/kg150 mg I/kg

HolmquistKristiansson

80 kVp 1680 kVp 16--MDCT for PEMDCT for PE

87 yrs, 43 kg, 156 cm 113 mol, eGFR 21

150 mg I/kg,12 sec inj time

20 ml, 320 mg I/mL6.4 gram-iodine

1.7 mL/s

g-I/GFR ratio 6/21 = 0.3

376 HU

394 HU

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Acta Radiol 2012;53:1004Acta Radiol 2012;53:1004--13.13.

EffectiveEffective dosesdoses in in ChestChest CTCT

•• BackgroundBackground radiationradiation/yr /yr -- SwedenSweden ~~3 3 mSvmSv

•• V/Q V/Q scintigraphyscintigraphy 2.4 2.4 mSvmSv•• www.ssi.sewww.ssi.se statisticsstatistics in Sweden 2005in Sweden 2005

•• CT CT pulmonarypulmonary angiographyangiography 1313--40 40 mSvmSv•• MettlerMettler et al. Radiology 2008;248:254et al. Radiology 2008;248:254--63.63.

•• CT thorax Sweden 2006CT thorax Sweden 2006 6.6 6.6 mSvmSv•• SSI SSI reportreport 2008:022008:02

•• Trelleborg 80 kVp/100 Trelleborg 80 kVp/100 mAsmAseffeff 1.2 1.2 mSvmSv

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3838--year old, pregnant 20th weekyear old, pregnant 20th weekLäkartidningen 2010;107(15);989-94.

Leung et al.

Radiology

2012;262:635-646

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Cancer risk per 100 000Cancer risk per 100 000

QQ--scintigraphyscintigraphy CTCT(half dose (half dose 50 MBq)50 MBq) (100 kVp/100 mAs)(100 kVp/100 mAs)

•• Breast Breast 0.50.5 15152 per mGy (30 yrs)2 per mGy (30 yrs) (0.25 mGy)(0.25 mGy) (7.5 mGy)(7.5 mGy)

•• Maternal lethal Maternal lethal 55 252510 per mSv (1010 per mSv (10--30yrs)30yrs) (0.5 mSv)(0.5 mSv) (2.5 mSv)(2.5 mSv)

•• Child lethal (<15 yrs)Child lethal (<15 yrs) 22 116 per mGy (<15 yrs)6 per mGy (<15 yrs) (0.37 mGy)(0.37 mGy) (0.13 mGy)(0.13 mGy)

DiagnosingDiagnosing PE in PE in pregnancypregnancy

•• DD--dimerdimer not in not in routineroutine

•• Symptoms of DVT Symptoms of DVT –– venousvenous ultrasoundultrasound

•• CXR (strong CXR (strong recommendationrecommendation of ATS/STR) of ATS/STR)

•• QQ--scintscint ((halfhalf dosedose) ) ifif CXR is normalCXR is normal•• less less radiationradiation to the to the mothermother, high , high raterate of of conclusiveconclusive examinations, examinations,

•• CT CT abnormalabnormal CXRCXR, V/Q , V/Q unavailableunavailable or or nonnon--diagnosticdiagnostic•• optimizeoptimize exposureexposure and and injectioninjection parameters!parameters!

•• InformInform mothermother -- risk of risk of anyany methodmethod for the baby and for the baby and herselfherself is far less is far less thanthan a a misdiagnosismisdiagnosis of PEof PE

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Sammanfattning

•Över- ej underdiagnostik största problemet

•Hö-kammarpåverkan kan identifieras

•Stråldoserna under kontroll

•Risk för kontrastnefropati minimalt problem

•Skint 1:a handsmetod för gravida, CT när skint

kan vara inkonklusivt eller inte är tillgängligt