Minimal Aortic Injury Detected on Computed Tomography Angiography during Initial Trauma Imaging: Single Academic Level 1 Trauma Center Experience.

BACKGROUND: Minimal aortic injury (MAI), a subtype of acute traumatic aortic injury, is being increasingly recognized with better imaging techniques. Given conservative management, the role of follow-up imaging albeit important yet has to be defined. METHODS: All trauma chest computed tomography angiographies (CTAs) at our center between January 2012 and January 2019 were retrospectively reviewed for presence of MAI. MAIs were generally reimaged at 24 to 72 hours and then at a 7- and 30-day interval. Follow-up CTAs were reviewed for stability, progression, or resolution of MAI, along with assessment of injury severity scores (ISS) and concomitant injuries, respectively. RESULTS: A total of 17,569 chest CTAs were performed over this period. Incidence of MAI on the initial chest CTA was 113 (0.65%), with 105 patients receiving follow-up CTAs. The first, second, third, and fourth follow-up CTAs were performed at a median of 2, 10, 28, and 261 days, respectively. Forty five (42.9%), 22 (21%), 5 (4.8%), and 1 (1%) of the MAIs were resolved by first, second, third, and fourth follow-up CTAs. Altogether, 21 patients showed stability (mean ISS of 16.6), and 11 demonstrated improvement (mean ISS 25.8) of MAIs. Eight patients had no follow-up CTA (mean ISS 21). No progression to higher-grade injury was observed. Advancing age decreased the odds of MAI resolution on follow-up. A possible trend (p-value 0.22) between increasing ISS and time to resolution of MAIs was noted. CONCLUSION: In our series of acute traumatic MAIs diagnosed on CTA imaging, there was no progression of injuries with conservative management, questioning the necessity of sequential follow-up imaging.

Influence of extracellular volume fraction on peak exercise oxygen pulse following thoracic radiotherapy.

BACKGROUND: Radiation-induced myocardial fibrosis increases heart failure (HF) risk and is associated with a restrictive cardiomyopathy phenotype. The myocardial extracellular volume fraction (ECVF) using contrast-enhanced cardiac magnetic resonance (CMR) quantifies the extent of fibrosis which, in severe cases, results in a noncompliant left ventricle (LV) with an inability to augment exercise stroke volume (SV). The peak exercise oxygen pulse (O2Pulse), a noninvasive surrogate for exercise SV, may provide mechanistic insight into cardiac reserve. The relationship between LV ECVF and O2Pulse following thoracic radiotherapy has not been explored. METHODS: Patients who underwent thoracic radiotherapy for chest malignancies with significant incidental heart dose (≥5 Gray (Gy), ≥10% heart) without a pre-cancer treatment history of HF underwent cardiopulmonary exercise testing to determine O2Pulse, contrast-enhanced CMR, and N-terminal pro-brain natriuretic peptide (NTproBNP) measurement. Multivariable-analyses were performed to identify factors associated with O2Pulse normalized for age/gender/anthropometrics. RESULTS: Thirty patients (median [IQR] age 63 [57-67] years, 18 [60%] female, 2.0 [0.6-3.8] years post-radiotherapy) were included. The peak VO2 was 1376 [1057-1552] mL·min- 1, peak HR = 150 [122-164] bpm, resulting in an O2Pulse of 9.2 [7.5-10.7] mL/beat or 82 (66-96) % of predicted. The ECVF, LV ejection fraction, heart volume receiving ≥10 Gy, and NTproBNP were independently associated with %O2Pulse (P < .001). CONCLUSIONS: In patients with prior radiotherapy heart exposure, %-predicted O2Pulse is inversely associated markers of diffuse fibrosis (ECVF), ventricular wall stress (NTproBNP), radiotherapy heart dose, and positively related to LV function. Increased LV ECVF may reflect a potential etiology of impaired LV SV reserve in patients receiving thoracic radiotherapy for chest malignancies.

Characterization of Chest Wall Toxicity During Long-term Follow Up After Thoracic Stereotactic Body Radiation Therapy.

PURPOSE: Chest wall (CW) pain and rib fractures are frequently diagnosed after stereotactic body radiation therapy (SBRT) for malignant lung tumors. We hypothesize that multiple risk factors, including bone mineral density (BMD), are associated with CW toxicity, and that CW pain and rib fractures often evolve into chronic clinical problems. METHODS AND MATERIALS: A total of 118 lung tumors treated with SBRT in 100 patients with a minimum follow-up period of 2 years were retrospectively analyzed. The incidence, clinical course, and related demographic, clinical, and dosimetric factors of CW pain and rib fractures were analyzed. In addition, BMD was assessed, and the radiographic appearance of radiation-induced rib fractures and their healing process were characterized. RESULTS: The median follow-up was 49 months (range, 24-106 months). CW pain developed in 33 of 118 treatments (28%) after, on average, 12.5 months (range, 0-50 months), and was more common in women (P = .04). The mean duration of CW pain was 25 months (range, 2-63 months), and 36% of patients never had resolution of CW pain. A total of 34 of 118 treatments (29%) resulted in rib fractures at a mean time of 22 months (range, 3-46 months); rib fractures were more common in women, African Americans, upper/middle lobe tumors, and patients with lower BMD (P < .05). The mean duration of rib fractures was 25 months (range, 5-41 months), and only 16 rib fractures (47%) healed. Shorter CW planning target volume distance resulted in a higher risk for both rib fractures and CW pain (P = .01). Sixty-seven percent of fractures developed surrounding soft tissue fibrosis, and 62% (21 of 34 fractures) heterotopic ossification. Diabetes, body mass index, and steroid use were not associated with CW pain or rib fracture. CONCLUSIONS: Several factors were associated with a higher risk of SBRT-related CW toxicity. Optimal CW sparing (eg, volumetric modulated arc therapy, lower dose per fraction) should be considered in this patient group without compromising tumor control. SBRT-induced rib fractures commonly heal abnormally and result in potential chronic CW pain.

Dissection of Ascending Aorta: A Complication of Transradial Artery Access of Coronary Procedure.

Iatrogenic acute dissection of ascending aorta following coronary angiography and percutaneous intervention is a rare complication. Most reports involve localized aortic dissections as a complication of cannulation of a coronary artery with propagation into the ascending aorta. It is usually treated by sealing the intima with a stent in the ostium of the coronary artery or conservative management, while extensive dissections may require a surgical intervention. We describe a case of the subclavian dissection extending into the ascending aorta that occurred during diagnostic catheterization using the radial approach. The patient was successfully treated utilizing conservative management.

Combining acute diffusion-weighted imaging and mean transmit time lesion volumes with National Institutes of Health Stroke Scale Score improves the prediction of acute stroke outcome.

BACKGROUND AND PURPOSE: The purpose of this study was to determine whether acute diffusion-weighted imaging (DWI) and mean transit time (MTT) lesion volumes and presenting National Institutes of Health Stroke Scale (NIHSS) can identify patients with acute ischemic stroke who will have a high probability of good and poor outcomes. METHODS: Fifty-four patients with acute ischemic stroke who had MRI within 9 hours of symptom onset and 3-month follow-up with modified Rankin scale were evaluated. Acute DWI and MTT lesion volumes and baseline NIHSS scores were calculated. Clinical outcomes were considered good if the modified Rankin Scale was 0 to 2. RESULTS: The 33 of 54 (61%) patients with good outcomes had significantly smaller DWI lesion volumes (P=0.0001), smaller MTT lesion volumes (P<0.0001), and lower NIHSS scores (P<0.0001) compared with those with poor outcomes. Receiver operating characteristic curves for DWI, MTT, and NIHSS relative to poor outcome had areas under the curve of 0.889, 0.854, and 0.930, respectively, which were not significantly different. DWI and MTT lesion volumes predicted outcome better than mismatch volume or percentage mismatch. All patients with a DWI volume >72 mL (13 of 54) and an NIHSS score >20 (6 of 54) had poor outcomes. All patients with an MTT volume of <47 mL (16 of 54) and an NIHSS score <8 (17 of 54) had good outcomes. Combining clinical and imaging thresholds improved prognostic yield (70%) over clinical (43%) or imaging (54%) thresholds alone (P=0.01). CONCLUSIONS: Combining quantitative DWI and MTT with NIHSS predicts good and poor outcomes with high probability and is superior to NIHSS alone.

Quantitative assessment of core/penumbra mismatch in acute stroke: CT and MR perfusion imaging are strongly correlated when sufficient brain volume is imaged.

BACKGROUND AND PURPOSE: Our purpose was to determine (1) the correlation between quantitative CT and MR measurements of infarct core, penumbra, and mismatch; and (2) whether the difference between these measurements would alter patient selection for stroke clinical trials. METHODS: We studied 45 patients with acute middle cerebral artery stroke imaged a mean of 3.8 hours after onset (range, 0.48 to 8.35 hours) who underwent CT perfusion and MR diffusion (DWI)/perfusion imaging within 3 hours of each other. The DWI and MR-mean transit time (MTT) abnormalities were visually segmented using a semiautomated commercial analysis program. The CT-cerebral blood volume) and CT-MTT lesions were automatically segmented using a relative cerebral blood volume threshold of 0.56 and a relative MTT threshold of 1.50 on commercially available software. Percent mismatch was defined as [(MTT-DWI)/DWI volume]x100. Pearson correlation coefficients were calculated. RESULTS: There were significant correlations for DWI versus CT-cerebral blood volume lesion volumes (r2=0.88, P<0.001), for MR-MTT versus CT-MTT lesion volumes(r2=0.86, P<0.001), and for MR-MTT/DWI versus CT-MTT/CT-cerebral blood volume mismatch lesion volumes(r2=0.81, P<0.001). MR perfusion and CT perfusion agreed for determining: (1) infarct core < versus >or=100 mL in 41 of 45 (91.1%); (2) MTT lesion size < versus >2 cm diameter in 42 of 45 (93.3%); (3) mismatch < versus >20% in 41 of 45 (91.1%); and (4) inclusion versus exclusion from trial enrollment in 38 of 45 (84.4%) patients. Six of 7 disagreements were due to inadequate CT coverage. CONCLUSIONS: Advanced MR and CT perfusion imaging measurements of core/penumbra mismatch for patient selection in stroke trials are highly correlated when CT perfusion coverage is sufficient to include most of the ischemic region. Although MR is currently the preferred imaging method for determining core and penumbra, CT perfusion is comparable and potentially more available.