8th Nordic Trauma Radiology Courseh24-files.s3.amazonaws.com/110213/557134-A3h7Q.pdf ·...
Transcript of 8th Nordic Trauma Radiology Courseh24-files.s3.amazonaws.com/110213/557134-A3h7Q.pdf ·...
MDCT of Traumatic Aortic Injury: New Concepts
Stuart E. Mirvis, MD, FACR
Department of Radiology & Maryland Shock-Trauma Center
University of Maryland School of Medicine
8th Nordic Trauma Radiology Course
Evolution in Diagnosis & Management of TAI
MDCT has improved sensitivity for detecting subtle TAI
As more patients are screened by CT ……increasing visualization of variant anatomy that can mimic TAI
MDCT reveals wider spectrum/nuances of TAI MH not a constant companion to TAI More treatment options requires more accurate
anatomical description of injuries and understanding their natural history
Rare cases still MCDT indeterminate* (IVUS, angio, endoluminal view, sonography)
*Sammer M, et al. Indeterminate CT Angiography in Blunt Thoracic Trauma:Is CT Angiography Enough? AJR 2007;189:603–608
Ductus remnant
Aortic spindle
Typical Aortic Injury Features
Location – 95+ % @ aortic isthmus Surrounding hematoma typical Pseudoaneurysm Intimal flaps Irregular, flattened contour Thrombus on flap Coarctation – 20-30% Small distal aorta – 10% Retrocrural hematoma – 20% Active bleed - rare
Typical Aortic Pseudoaneurysms
Aortic Coarctation / Small Aorta Sign
Thoracic spine fracture-dislocation and aortic wall hematoma
Distractive or translational force
Rare: 8 of 11,465 trauma admissions
From intimal tear to full thickness injury
Traumatic Aortic Dissection
Aortic injury embolism
Ductus and ductus variants
Diverticular Origin of Bronchial Artery
Aortic Injury Classification
Minor TAI: Contour irregularity, intimal flap +/- attached clot, intramural hematoma, pseudoaneurysm < 10% “normal” aortic diameter at same level (very conservative)
Major TAI: active bleeding, pseudoaneurysm > 10% of normal aortic diameter at same level, dissection
MH: Presence or absent
Minor Pseudoaneurysm
Minor Pseudoaneurysm
Contour Abnormality
Minor Aortic Injuries
Day 1 Day 1 Day 1
Day 2 Day 2 Day 8
Minor TAI – Intima and clot – Minimal MH Resolved
Day 8
Minor intimal tear - No MH
2 days later – no treatment
Day 0
Day 8
Day 28
Patients and Methods
IRB and HIPAA compliant Retrospective review of patients through Shock-Trauma Registry
(Jan. 2005 to May 2011) Excluded patients expired or had thoracic surgery before MDCT All CTs (initial and any F/U) reviewed by consensus of 3 radiologists
for TAI and +/- MH Determined management from imaging studies and medical records Injury status at time of last MDCT F/U 40 or 64-slice MDCT with 100 ml of 350mg% IV contrast and 50 ml
saline flush and full body scan technique Fischer’s Exact Test assessed probability of association between
TAI grade and MH (present/absent)
Results 115 patients (0.3%) with TAI among 40,479 admits 6.5
yr 42 classified as minor; 73 as major Minor TAI: 76% intimal flap, 24% shallow
pseudoaneurysm Among 42 minor – 23 treated without intervention;15
stented; 2 surgery (both 2005); 2 died before imaging (non-aortic cause)
33 of 42 (79%) minor injuries with MH and 9 (21%) had no MH; 3 of 73 major (4%) TAI no MH
Correlation of TAI grade and present/absent MH (p=0.0001) by Fischer exact test
Results
33 of 42 (79%) pts. had CT-A follow-up 21/33 (64%) stable;5(15%) improved;7
(21%) resolved Mean F/U = 32d, median 7d, range 1-210d
In press, European Radiology
Gavant ML. Helical CT grading of traumatic aortic injuries: Impact on clinical guidelines for medical and surgical management. Radiol Clinics of N Am. 1999;37:553-574.
Presley Trauma Center Grading System of Aortic Injury I. Normal aorta a. Nl thoracic aorta
b. Nl aorta + MH II. Minimal aortic injury a. Flap, PsAn < 1 cm. No MH b. Flap, PsAn < 1 cm. + MH III. Confined TAI a. > 1 cm well-defined PsAn with flap or thrombus. No great vessels injury + MH b. > 1 cm well-defined PsAn with flap or thrombus; not isthmic aortic site, +MH IV. Total disruption with irregular poorly defined PsAn and MH
Examples of minor TAI from Elvis Presley Trauma Center Criteria (Memphis)
Paul et al. Minimal aortic injury after blunt trauma: Selective nonoperative management is safe. J Trauma. 2011;71:1519-23
Minor Aortic Injury Retrospective, N=47 with BAI 15 (32%) classified MAI (11 intimal flaps, 2
< 1 cm). All treated without intervention and survived with no aortic morbidity
Median 4 day f/u by CT-A (5 resolved, 8 stable) 2 neg. by aortogram
Injury grade by consensus of Presley System Variable management of <1 cm PsAn
Definitions of minor aortic injury in literature Study Definition #Patients with minor TAI Pate et al. [15] Intimal defect causing a 6 (3 developed small aortic diameter luminal compromise of <10% pseudoaneurysms) Malhotra AK, et al. [5] Intima flap <1 cm in size with no 31 (22% of TAI) (G1=23; or minimal MH G2 = 8)) Starnes BW, et al. [12] G1 Absent external contour abnormality:intimal G1=14, G2= 8 (all survived, but flap and/or thrombus <10mm.G2- same as most G2 treated by stent) above >10mm length Paul JS, et al. [13] Intimal flap or pseudoaneurysm <1 cm 15 (32% all TAI) all TAI with or without mediastinal hematoma Mosquera VX, et al. [10] 9 (16% all TAI); no aorta related death 5 yr F/U Azizzadeh, et al. [17] G1 (intimal tear) G2 (intramural hematoma) 10 (14% all TAI) (all G1) G3 (pseudoaneurysm) G4(free rupture) Reisenman PJ, et al. [8] 5 (Grade 1);1 had aortic stent for progression to pseudoaneurysm @ 9 months
Current studies are coalescing towards a definition of minor aortic injury
A minor TAI should permit safe non-interventional management
A prospective study using with a “fixed” anatomical definition of “minor” is required. (Needs multiple institutions)
Study requires a patient group that is consistently managed with predetermined frequency/duration of CT-A follow-up
Conclusions