Variations in the Anterolateral Thigh Flap's Vascular Anatomy in African Americans.

BACKGROUND: Variations in anterolateral thigh (ALT) arterial anatomy are well documented. Ethnicity is a known risk factor for vascular variation in several organ systems, but its impact on ALT anatomy has not been studied. Anecdotally, we observed frequent ALT arterial variation in African American (AA) patients. We thus hypothesized that AA patients have higher rates of anomalous branching. MATERIALS AND METHODS: A total of 277 computed tomography angiograms (513 lower extremities) captured between May 1, 2013 and May 31, 2015 at a tertiary academic medical center were retrospectively analyzed to determine ALT arterial branching. Patient records were examined to ascertain demographics. Data were analyzed using descriptive statistics and multinomial logistic regression. RESULTS: Males comprised 84.5%. Ethnic distribution was 55.2% AA and 36.5% Caucasian. The descending branch of the lateral circumflex femoral artery (dLCFA) originated from non-LCFA arteries (deep femoral, common femoral, or superficial femoral arteries) in 18.9% of Caucasian versus 9.1% of AA (odds ratio [OR]: 2.28; 95% confidence interval [CI]: 1.33-3.93, p < 0.01). An oblique branch was identified in 41.1% of Caucasian versus 51.9% of AA (OR: 1.56; 95% CI: 1.08-2.24, p = 0.02). Ethnicity was the only driving factor of dLCFA and oblique branch of the LCFA (oLCFA) anatomy (Wald chi-square: 14 and 11, p = 0.03 and 0.02, respectively). CONCLUSIONS: Ethnicity significantly affects ALT arterial anatomy. AA are more likely to have classical dLCFA branching with a fourth oLCFA branch. A flap with an unrecognized oLCFA-dominant supply places patients at a higher risk for flap failure and loss. We recommend preoperative imaging before undertaking an ALT flap reconstruction.

Follow-up Recommendation Rates Associated With Spectral Detector Dual-Energy CT of the Abdomen and Pelvis: A Retrospective Comparison to Single-Energy CT.

BACKGROUND: Dual-energy CT image sets have many applications in abdominopelvic imaging but no demonstrated clinical effect. PURPOSE: To determine the effect of dual-energy CT iodine maps on abdominopelvic imaging follow-up recommendation rates. MATERIALS AND METHODS: Retrospective study of abdominopelvic CTs acquired from April 2017 through June 2018. CT reports were analyzed for radiologic follow-up recommendation and follow-up recommendation reason. Follow-up MRI reports were analyzed for benign or nonbenign diagnosis. CT scans with iodine maps (CTIMs) and conventional CT scans (CCTs) subgroups were compared using χ2 testing. RESULTS: In all, 3,221 abdominopelvic CT scans of 2,401 patients (1,326 men, 1,075 women, mean age 54.1 years) were analyzed; 1,423 were CTIMs and 1,798 were CCTs. Follow-up recommendation rates were not significantly different for CTIMs and CCTs (19.5% and 21.4%, respectively, P = .19). Follow-up recommendations because of incomplete diagnosis were significantly lower in CTIMs (9.1%) than in CCTs (11.9%, P = .01). Follow-up recommendations for MRI and PET/CT were significantly lower in CTIMs (9.6%) than CCTs (13.0%, P = .003). Follow-up MRI outcomes (n = 111) were not different between CTIMs (61.2% benign) and CCTs (59.6%, P = .87). CONCLUSION: Dual-energy CT iodine maps are associated with decreased follow-up examinations because of incomplete diagnosis and decreased recommendations for follow-up MRI, suggesting that abdominopelvic iodine maps may benefit patient care and decrease institutional cost.

Dual-energy CT in the obese: a preliminary retrospective review to evaluate quality and feasibility of the single-source dual-detector implementation.

PURPOSE: To determine the feasibility of performing dual-energy CT with a single-source spectral detector system in obese patients. MATERIALS AND METHODS: Retrospective, IRB-approved review of 28 patients weighing ≥ 270 lbs (122 kg) who underwent CT of the abdomen on a single-source spectral detector system was performed. Two blinded, independent radiologists rated relative preference between conventional CT images taken at 120 kVp (CCT120) and monoenergetic 70 keV equivalent (MonoE70) as well as iodine map image quality in the spleen, pancreas, kidneys, and liver. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared between conventional CT and MonoE70 images and correlated with body habitus markers of weight, height, and abdominal diameter. RESULTS: MonoE70 images were preferred by radiologists 100% of the time (1-sample t test, p < 0.0001) over conventional CCT120 images. Noise was significantly lower; SNR and CNR were significantly higher in MonoE70 images than in CCT120 images (paired t tests, p < 0.0001). Mean iodine map rating (scale 1-5) was 4.54 ± 0.58, denoting near homogenous and complete iodine mapping through the spleen, pancreas, kidneys, and liver for the majority of patients. Body habitus markers were not significantly correlated with image preference score; noise; MonoE70 SNR; MonoE70 CNR; change in noise, SNR, or CNR from CCT120 to MonoE70, or iodine map quality; ordinal and linear regression, p = 0.2547, p = 0.6837, p = 0.1888, p = 0.5489, p = 0.9830, p = 0.8849, p = 0.8741, p = 0.1522, respectively. CONCLUSION: The single-source spectral detector implementation of dual-energy CT provides viable, high-quality imaging for obese patients.