Predictive Value of CT Biomarkers in Lung Transplantation Survival: Preliminary Investigation in a Diverse, Underserved, Urban Population.

INTRODUCTION: Survival following lung transplant is low. With limited donor lung availability, predicting post-transplant survival is key. We investigated the predictive value of pre-transplant CT biomarkers on survival. METHODS: In this single-center retrospective cohort study of adults in a diverse, underserved, urban lung transplant program (11/8/2017-5/20/2022), chest CTs were analyzed using TeraRecon to assess musculature, fat, and bone. Erector spinae and pectoralis muscle area and attenuation were analyzed. Sarcopenia thresholds were 34.3 (women) and 38.5 (men) Hounsfield Units (HU). Visceral and subcutaneous fat area and HU, and vertebral body HU were measured. Demographics and pre-transplant metrics were recorded. Survival analyses included Kaplan-Meier and Cox proportional hazard. RESULTS: The study cohort comprised 131 patients, 50 women, mean age 60.82 (SD 10.15) years, and mean follow-up 1.78 (SD 1.23) years. Twenty-nine percent were White. Mortality was 32.1%. Kaplan-Meier curves did not follow the proportional hazard assumption for sex, so analysis was stratified. Pre-transplant EMR metrics did not predict survival. Women without sarcopenia at erector spinae or pectoralis had 100% survival (p = 0.007). Sarcopenia did not predict survival in men and muscle area did not predict survival in either sex. Men with higher visceral fat area and HU had decreased survival (p = 0.02). Higher vertebral body density predicted improved survival in men (p = 0.026) and women (p = 0.045). CONCLUSION: Pre-transplantation CT biomarkers had predictive value in lung transplant survival and varied by sex. The absence of sarcopenia in women, lower visceral fat attenuation and area in men, and higher vertebral body density in both sexes predicted survival in our diverse, urban population.

Using Routine Chest Computed Tomography to Diagnose Pulmonary Embolism.

OBJECTIVE: This study investigated the use of routine contrast-enhanced chest computed tomography (CT) to diagnose unsuspected pulmonary embolism (PE). METHODS: All adult routine contrast-enhanced chest CTs performed at Montefiore in 2018 were included. Pulmonary artery enhancement was measured by placing regions of interest in the pulmonary vasculature. Adequate enhancement was defined as 200 Hounsfield units (HU) or greater. Presence or absence of PE was noted. Descriptive statistics and logistic regression analysis were performed. RESULTS: A total of 3164 CTs were evaluated (55.8% women; mean age, 63.2 years). Main pulmonary enhancement was highly correlated with peripheral enhancement. Of all cases, 28.7% (907 of 3164) reached the 200 HU threshold. Greater enhancement was associated with female sex, older age, outpatients, and contrast amount administered. Pulmonary embolism-positive cases comprised 1.8% (58 of 3164) of total cases. Furthermore, 39.7% (23 of 58) of PE-positive cases reached the 200 HU threshold. CONCLUSIONS: Over one quarter of routine contrast-enhanced chest CT scans met the 200 HU threshold indicative of adequate pulmonary artery enhancement, including nearly half of the 2% of examinations positive for PE.

Non-traumatic hemoperitoneum in the ED setting: causes, characteristics, prevalence and sex differences.

PURPOSE: Prevalence and sex differences of non-traumatic hemoperitoneum in the Emergency Department has not been studied in the literature. METHODS: Following IRB approval, multiple keyword searches were used to identify all cases of hemoperitoneum over a 55-month period. Cases were reviewed to confirm and quantify the hemoperitoneum. Maximum attenuation was used to grade blood density. Medical records were reviewed to determine cause, interventions and outcomes in each patient. RESULTS: Of the 171 verified cases of non-traumatic hemoperitoneum, 76% of cases were in women. CT exams in women were positive for hemoperitoneum 0.25% of the time, while 0.13% were positive in men. Regarding size, 25.7% were large, 24.5% were moderate and 49.7% were small. Contrast-enhanced studies had HU values of 103 ± 19 (range 47-146) which were significantly higher than for non-enhanced studies with values of 82 ± 19 (range 43-121, p < 0.001). The most common cause of non-traumatic hemoperitoneum was ruptured ovarian cyst which was found in 58% of women (76 cases). Of these, 69 patients received observation, 6 patients underwent surgery and 1 patient received Vitamin K. For the 95 non-ovarian cyst cases, 65% patients were admitted and then discharged, 22% were discharged from the ED, 12% expired and 1% were transferred to a different hospital. Post-procedure hemorrhage was the second to most common cause in women (24/130 = 18%) and the most common etiology in men (14/41 = 34%). CONCLUSIONS: In women, ovarian cyst rupture was the most common etiology of hemoperitoneum. Post-procedure hemorrhage was second in women and the most common etiology in men. Although unusual causes of hemoperitoneum will be encountered, understanding the most common causes of hemoperitoneum can provide a reasonable starting point when attempting to determine the most likely etiology of hemoperitoneum in any individual patient.

Ventricular Myocardial Fat: An Unexpected Biomarker for Long-term Survival?

PURPOSE: To examine the association between myocardial fat, a poorly understood finding frequently observed on non-contrast CT, and all-cause mortality in patients with and without a history of prior MI. MATERIALS AND METHODS: A retrospective cohort from a diverse urban academic center was derived from chronic myocardial infarction (MI) patients (n = 265) and three age-matched patients without MI (n = 690) who underwent non-contrast chest CT between 1 January 2005-31 December 2008. CT images were reviewed for left and right ventricular fat. Electronic records identified clinical variables. Kaplan-Meier and Cox proportional hazard analyses assessed the association between myocardial fat and all-cause mortality. The net reclassification improvement assessed the utility of adding myocardial fat to traditional risk prediction models. RESULTS: Mortality was 40.1% for the no MI and 71.7% for the MI groups (median follow-up, 6.8 years; mean age, 73.7 ± 10.6 years). In the no MI group, 25.7% had LV and 49.9% RV fat. In the MI group, 32.8% had LV and 42.3% RV fat. LV and RV fat was highly associated (OR 5.3, p < 0.001). Ventricular fat was not associated with cardiovascular risk factors. Myocardial fat was associated with a reduction in the adjusted hazard of death for both the no MI (25%, p = 0.04) and the MI group (31%, p = 0.018). Myocardial fat resulted in the correct reclassification of 22% for the no MI group versus the Charlson score or calcium score (p = 0.004) and 47% for the MI group versus the Charlson score (p = 0.0006). CONCLUSIONS: Patients with myocardial fat have better survival, regardless of MI status, suggesting that myocardial fat is a beneficial biomarker and may improve risk stratification. KEY POINTS: • Myocardial fat is commonly found on chest CT, yet is poorly understood • Myocardial fat is associated with better survival in patients with and without prior MI and is not associated with traditional cardiovascular risk factors • This finding may provide clinically meaningful prognostic value in the risk stratification of patients.

Patent foramen ovale in patients with pulmonary embolism: A prognostic factor on CT pulmonary angiography?

BACKGROUND: Patent foramen ovale (PFO) in patients with acute pulmonary embolism (PE) represents a risk factor for mortality, but this has not been evaluated for CT pulmonary angiography (CTPA). The purpose of the present study was to assess the relationship between PFO and mortality in patients with acute PE diagnosed on CTPA. MATERIALS AND METHODS: This retrospective study included 268 adults [173 women, mean age 61 (range 22-98) years] diagnosed with acute PE on non-ECG-gated 64-slice CTPA in 2012 at our medical center. The images were reviewed for PFO by a panel of cardiothoracic radiologists with an average of 11 years of experience (range 1-25 years). CT signs of right heart strain and PE level were noted. Transthoracic echocardiograms (TTE), when available (n = 207), were reviewed for PFO by a cardiologist with subspecialty training in advanced imaging and with 3 years of experience. The main outcome was 30-day mortality. Fischer's exact test was utilized to compare mortality. RESULTS: PFO prevalence on CTPA was 22% (58/268) and 4% (9/207) on TTE. Overall 30-day mortality was 6% (16/268), 9% (5/58) for patients with PFO and 5% (11/210) for those without (p = 0.35). CT signs of right heart strain trended with higher mortality, but statistically significant only for hepatic vein contrast reflux [14% (6/44) vs 4% (10/224), p = 0.03]; right ventricular (RV) to left ventricular (LV) diameter ratio >1 [8% (13/156) vs RV:LV ≤ 1 3% (3/112), p = 0.07], septal bowing [10% (4/42) vs without 5% (12/226), p = 0.30]. CONCLUSION: PFO was demonstrated on CTPA in a proportion similar to the known population prevalence, while routine TTE was less sensitive. Mortality was non-significantly higher in patients with acute PE and PFO in this moderate-sized study. A larger study to answer this clinically important question is worthwhile.

High attenuation pericardial fluid on CT following cardiac catheterization.

High-density pericardial fluid may be seen on noncontrast CT performed following cardiac catheterization (CC), raising the possibility of hemopericardium. Our goal was to determine the clinical course and associations of incidentally discovered high-attenuation pericardial fluid on noncontrast CT performed soon after CC. Hospital database search over a 7.5-year period identified 211 patients who underwent CT of the chest and/or abdomen within 60 h before or after CC, 150 having CC first. Pericardial fluid volume and attenuation as well as relevant laboratory and clinical parameters were recorded. Bivariate associations with average pericardial fluid attenuation (HUavg) were assessed. Using the 61 patients with CT before CC as controls, 44 of the patients with CC first had attenuation values greater than the mean + 2SD of 22.6 Hounsfield unit (HU) and 19 had attenuation values greater than the maximum control patient value of 39.8 HU. All patients with incidental finding of high-density pericardial fluid followed a benign course. Bivariate correlations showed time gap between CC and CT (rho = -0.50, p < 0.001), estimated glomerular filtration rate (eGFR) (rho = -0.24, p = 0.004), and female gender (median (IQR) 17.4 (13.6, 29.6) vs. 15.8 (9.9, 23.7), p = 0.02) to be associated with HUavg. In multiple linear regression analysis, only time gap and female gender were independently significantly associated with average attenuation (both p < 0.001). The finding that patients with incidentally discovered high-density pericardial fluid followed an uneventful course suggests a benign etiology such as vicarious excretion, and in patients who are otherwise stable, observation rather than immediate intervention should be considered.

Evaluation of the cardiac chambers on axial CT: comparison with echocardiography.

OBJECTIVE: To evaluate qualitative and simple quantitative measures of all 4 cardiac chamber sizes on computed tomography (CT) in comparison with transthoracic echocardiography (TTE). METHODS: We retrospectively identified 104 adults with electrocardiographically gated cardiac CT and TTE within 3 months. Axial early diastolic (75% R-R) CT images were reviewed for qualitative chamber enlargement, and each chamber was measured linearly. Transthoracic echocardiography was reviewed for linear, area, and volume measurements. Interrater agreement was calculated using Cohen κ and Pearson correlation. RESULTS: There were significant correlations between linear left atrium and left ventricle sizes by CT and TTE (r = 0.686 and r = 0.709, respectively). Correlations for right atrium and right ventricle measurements were lower (r = 0.447 and r = 0.492, respectively). Agreement between CT and TTE for qualitative chamber enlargement was poor (highest κ = 0.35). Computed tomography sensitivity was ≤ 62% for enlargement of all chambers. CONCLUSIONS: Linear CT measurements of left-sided chamber sizes correlate well with TTE. Right heart measurements and qualitative assessments agreed poorly with TTE.

Retained fibrin sheaths: chest computed tomography findings and clinical associations.

PURPOSE: Fibrin sheaths may develop around long-term indwelling central venous catheters (CVCs) and remain in place after the catheters are removed. We evaluated the prevalence, computed tomographic (CT) appearance, and clinical associations of retained fibrin sheaths after CVC removal. MATERIALS AND METHODS: We retrospectively identified 147 adults (77 men and 70 women; mean age 58 y) who underwent CT after CVC removal. The prevalence of fibrin sheath remnants was calculated. Bivariate and multivariate analyses were performed to assess for associations between sheath remnants and underlying diagnoses leading to CVC placement; patients' age and sex; venous stenosis, occlusion, and collaterals; CVC infection; and pulmonary embolism. RESULTS: Retained fibrin sheaths were present in 13.6% (20/147) of cases, of which 45% (9/20) were calcified. Bivariate analysis revealed sheath remnants to be more common in women than in men [23% (16/70) vs. 5% (4/77), P=0.0018] and to be more commonly associated with venous occlusion and collaterals [30% (6/20) vs. 5% (6/127), P=0.0001 and 30% (6/20) vs. 6% (7/127), P=0.0003, respectively]. Other variables were not associated. Multivariate analysis confirmed the relationship between fibrin sheaths and both female sex (P=0.005) and venous occlusion (P=0.01). CONCLUSIONS: Retained fibrin sheaths were seen on CT in a substantial minority of patients after CVC removal; nearly half of them were calcified. They were more common in women and associated with venous occlusion.

A new, simple method for estimating pleural effusion size on CT scans.

BACKGROUND: There is no standardized system to grade pleural effusion size on CT scans. A validated, systematic grading system would improve communication of findings and may help determine the need for imaging guidance for thoracentesis. METHODS: CT scans of 34 patients demonstrating a wide range of pleural effusion sizes were measured with a volume segmentation tool and reviewed for qualitative and simple quantitative features related to size. A classification rule was developed using the features that best predicted size and distinguished among small, moderate, and large effusions. Inter-reader agreement for effusion size was assessed on the CT scans for three groups of physicians (radiology residents, pulmonologists, and cardiothoracic radiologists) before and after implementation of the classification rule. RESULTS: The CT imaging features found to best classify effusions as small, moderate, or large were anteroposterior (AP) quartile and maximum AP depth measured at the midclavicular line. According to the decision rule, first AP-quartile effusions are small, second AP-quartile effusions are moderate, and third or fourth AP-quartile effusions are large. In borderline cases, AP depth is measured with 3-cm and 10-cm thresholds for the upper limit of small and moderate, respectively. Use of the rule improved interobserver agreement from κ = 0.56 to 0.79 for all physicians, 0.59 to 0.73 for radiology residents, 0.54 to 0.76 for pulmonologists, and 0.74 to 0.85 for cardiothoracic radiologists. CONCLUSIONS: A simple, two-step decision rule for sizing pleural effusions on CT scans improves interobserver agreement from moderate to substantial levels.

Acute aortic syndromes: a second look at dual-phase CT.

OBJECTIVE: The purpose of this article is to assess the diagnostic performance of the unenhanced and contrast-enhanced phases separately in patients imaged with CT for suspected acute aortic syndromes. MATERIALS AND METHODS: All adults (n = 2868) presenting to our emergency department from January 1, 2006, through August 1, 2010, who underwent unenhanced and contrast-enhanced CT of the chest and abdomen for suspected acute aortic syndrome were retrospectively identified. Forty-five patients with acute aortic syndrome and 45 healthy control subjects comprised the study population (55 women; mean age, 61 ± 16 years). Unenhanced followed by contrast-enhanced CT angiography (CTA) images were reviewed. Contrast-enhanced CTA examinations of case patients and control subjects with isolated intramural hematoma were reviewed. Radiation exposure was estimated by CT dose-length product. RESULTS: Forty-five patients had one or more CT findings of acute aortic syndrome: aortic dissection (n = 32), intramural hematoma (n = 27), aortic rupture (n = 10), impending rupture (n = 4), and penetrating atherosclerotic ulcer (n = 2). Unenhanced CT was 89% (40/45) sensitive and 100% (45/45) specific for acute aortic syndrome. Unenhanced CT was 94% (17/18) and 71% (10/14) sensitive for type A and type B dissection, respectively (p = 0.142). Contrast-enhanced CTA was 100% (8/8) sensitive for isolated intramural hematoma. Mean radiation effective dose was 43 ± 20 mSv. CONCLUSION: Unenhanced CT performed well in detection of acute aortic syndrome treated surgically, although its performance does not support its use in place of contrast-enhanced CTA. Unenhanced CT may be a reasonable first examination for rapid triage when IV contrast is contraindicated. Contrast-enhanced CTA was highly sensitive for intramural hematoma, suggesting that unenhanced imaging may not always be needed. Acute aortic syndrome imaging protocols should be optimized to reduce radiation dose.

Resting cardiac 64-MDCT does not reliably detect myocardial ischemia identified by radionuclide imaging.

OBJECTIVE: CT myocardial perfusion imaging is an emerging diagnostic modality that is under intensive study but not yet widely used in clinical practice. The purpose of this study is to evaluate the performance of resting 64-MDCT in revealing ischemia identified on radionuclide myocardial perfusion imaging (MPI). MATERIALS AND METHODS: We retrospectively identified 35 patients (20 women and 15 men; mean age, 52 years) with myocardial ischemia found on MPI who underwent retrospectively gated CT within 90 days of MPI. Myocardial perfusion on CT was evaluated using both a visual (n = 35) and an automated (n = 34) method. For the visual method, myocardial segments were evaluated qualitatively in systole and diastole. For the automated method, subendocardial perfusion of the standard 17 American Heart Association segments was measured using a commercially available tool in both systole and diastole. Differences between systolic and diastolic perfusion were computed. RESULTS: Five hundred eighty myocardial segments were evaluated, 152 of which were ischemic on MPI. Visual analysis had a sensitivity of 16% (24/152), specificity of 92% (393/428), positive predictive value of 40% (24/60), and negative predictive value of 75% (392/520) in systole, and a sensitivity of 18% (27/152), specificity of 89% (382/428), positive predictive value of 37% (27/73), and negative predictive value of 75% (382/507) in diastole, as compared with MPI. There was no significant difference in subendocardial perfusion between ischemic and nonischemic segments by the automated method. There was no significant difference in CT perfusion between patients with and without obstructive coronary artery disease on CT angiography using the visual or automated methods. CONCLUSION: Resting 64-MDCT is unsuitable for clinical use in revealing ischemia seen on MPI.

Postlobectomy chest radiographic changes: a quantitative analysis.

PURPOSE: To provide a quantitative analysis of postlobectomy chest radiographic changes and to evaluate whether the scarring from prior sternotomy affects the size of the hemithorax and the duration of air leak in patients with subsequent lobectomy. METHODS: In this retrospective case-controlled series, 10 consecutive patients who had a lobectomy after a prior sternotomy and 30 controls, 3 for each case, matched for lobectomy site were identified. Pre- and postoperative chest radiographs were quantitatively analysed for diaphragmic elevation, size of each hemithorax, mediastinal shift, and the presence of pneumothorax. Charts were reviewed for air-leak duration, surgical complications, and duration of hospitalization. RESULTS: There was no difference between patients with lobectomy and with and without prior sternotomy for the following variables expressed as mean (SD): hemidiaphragm elevation (1.5 ± 2.5 vs 0.5 ± 2.0 cm; P = .2), change of hemithorax size (mean transverse, 0.99 ± 0.05 vs 0.97 ± 0.07; P = .5; craniocaudal, 0.93 ± 0.08 vs 0.91 ± 0.08; P = .4) and mediastinal shift (upper, 1.2 ± 0.4 vs 1.3 ± 0.6; P = .5; lower, 1.2 ± 0.4 vs 1.2 ± 0.3; P = .8), the latter 2 were expressed as the ratio of post- to preoperative measurements. These postlobectomy radiographic findings varied, depending on the resected lobe, and became progressively more pronounced during the first 12 months after surgery. There was no difference in pneumothorax duration (mean [SD]) (9.5 ± 21 days vs 6.4 ± 7.5 days; P = .5), air leak duration (mean [SD]) (0.7 ± 0.8 days vs 1.3 ± 3.9 days; P = .6), complication rate (20% vs 30%; P = .5), or hospital stay (mean [SD]) (6.0 ± 1.7 days vs 6.9 ± 4.7 days; P = .6). CONCLUSION: There are specific patterns of volume loss, mediastinal shift, and hemidiaphragm displacement that can be quantified on postlobectomy chest radiographs. Prior sternotomy did not affect postlobectomy radiographic changes or patient outcome.

Should CT play a greater role in preventing the resection of granulomas in the era of PET?

OBJECTIVE: PET cannot distinguish between bronchogenic carcinoma and granuloma, but positive scans may prompt surgery. We systematically evaluated the CT appearance of resected carcinomas and granulomas to identify features that could be used to reduce granuloma resections. MATERIALS AND METHODS: We retrospectively identified 93 consecutive patients between January 2005 and November 2008 who had resection of a pulmonary nodule pathologically diagnosed as bronchogenic carcinoma or granuloma and preoperative imaging with CT and PET. Each nodule was evaluated on CT for size, doubling time, location, borders, shape, internal characteristics, calcification, clustering, air bronchograms, and cavitation. A diagnostic impression was rendered. Bivariate and logistic regression analyses were performed. Pre-PET data regarding the proportion of resected granulomas and carcinomas between January 1995 and December 1996 were reviewed. RESULTS: Sixty-eight percent (65/96) of nodules were carcinomas and 32% (31/96) were granulomas. The CT impression was benign in 65% (20/31) of granulomas and 5% (3/65) of carcinomas (p < 0.0001; negative predictive value [NPV], 87% [20/23]). Specific CT features significantly associated with granuloma were clustering, cavitation, irregular shape, lack of pleural tags, and solid attenuation. The combination of nonspiculated borders, irregular shape, and solid attenuation had an NPV of 86% (12/14). Granulomas represented 18% (9/50) of resected nodules in 1995 and 1996 (p = 0.066). CONCLUSION: CT findings reduce but cannot eliminate the possibility that a nodule is malignant. Outcomes-based clinical trials are needed to determine whether CT features of benignity can guide less-invasive initial management and reverse a concerning trend in granuloma resection.

Normal myocardial perfusion on 64-detector resting cardiac CT.

BACKGROUND: Computed tomography (CT) of the heart is increasingly used to characterize not only the coronary arteries but also cardiac structure and function. The performance of CT in depicting myocardial perfusion is under active investigation. OBJECTIVE: We describe the pattern of normal myocardial perfusion on resting 64-detector cardiac CT. METHODS: Patients (n = 33; 20 women, 13 men; mean age, 52 years) with normal radionuclide myocardial perfusion imaging and normal coronary arteries on CT angiography (120 kVp) comprised the study population. Segmental myocardial perfusion on CT was measured in Hounsfield units (HU) with manual and semiautomated methods for the 17-segment American Heart Association model in both systole and diastole. Segments were aggregated into coronary artery territories, from apex to base and by myocardial wall. The relationships between myocardial perfusion and various patient factors were evaluated. RESULTS: Overall mean myocardial perfusion was 98 HU in systole and 94 HU in diastole with the manual method (P = .011) and 92 HU in systole and 95 HU in diastole with the automated method (P = .001). The septum showed significantly higher mean attenuation values than the other walls in systole and diastole with both methods. Generally, attenuation values were lower in the left circumflex artery territory and in the apex. Bivariate analysis showed higher mean myocardial attenuation values for women than men, although this difference did not persist on multivariate analysis adjusted for patient size. CONCLUSION: Normal mean resting myocardial perfusion correlates with CT attenuation values of approximately 92-98 HU on CT angiography in the coronary arterial phase. The septum consistently shows greater attenuation values than the other walls.

Chest radiographs are valuable in demonstrating clinically significant pacemaker complications that require reoperation.

PURPOSE: To evaluate the utility of chest radiography in demonstrating clinically significant pacemaker complications that required reoperation. METHODS: In this retrospective case-controlled series, we identified 14 consecutive adults who required pacemaker reoperation and who had chest radiographs available for review (6 men, 8 women; mean age, 71 years [range, 43-95 years]). Ten patients had pacemakers implanted at our institution, and 4 were referred for reoperation. Forty-two controls, 3 for each patient, had postoperative chest radiographs and normal device function (25 men, 17 women; mean age 76 years [range, 37-96 years]). All postoperative chest radiographs, including 1-year follow-ups, were blindly reviewed by at least 2 of 4 radiologists for lead perforation and position of right atrial and right ventricular leads. Follow-up radiographs were assessed for lead perforation, lead displacement, and lead fracture. Data were analysed by using the Fisher exact test. RESULTS: Of the patients, 1.7% (10/581) required reoperation for pacemaker dysfunction (noncapture, oversensing, abnormal atrial and ventricular thresholds, failing impedance), extracardiac stimulation, and lead perforation and/or displacement. There were no lead fractures. Chest radiographs demonstrated pacemaker complications in 57% of patients (8/14) at a median of 2 days (<1-32 days) after implantation and in 5% of the controls (2/42) (P < .0001). None of the abnormalities were noted on the official reports. Among subgroups, chest radiographs were abnormal for the following indications: pacemaker dysfunction in 4 of 7 patients versus 0 of 21 controls (P = .0017), extracardiac stimulation in 1 of 3 patients vs 0 of 9 controls (P = .25), and lead perforation and/or displacement in 3 of 4 patients vs 2 of 12 controls (P = .06). CONCLUSIONS: Chest radiographs are useful after pacemaker placement and demonstrate the majority of complications that require reoperation. Familiarity with the expected normal position of the leads, appearances of pacemaker complications, and comparison with prior radiographs is crucial in rendering a correct diagnosis that guides patient management.

A man with a horseshoe adrenal gland associated with a midline posterior diaphragmatic defect.

We present a case of a horseshoe adrenal gland and a posterior midline diaphragmatic defect found incidentally on computed tomography in a 60-year-old man. It is, to our knowledge, the first case in an adult and represents a relatively innocuous developmental abnormality when compared with the previously described fetal and infantile adrenal fusion syndrome. This case demonstrates the importance of cross-sectional imaging and the effectiveness of computed tomography in defining the spectrum of congenital anomalies.

Ejection fractions determined by cardiac computed tomographic angiography and single photon emission computed tomographic myocardial perfusion imaging are not interchangeable: evidence of significant and sex-associated disparities.

PURPOSE: Left ventricular ejection fraction (LVEF) determines patient management and is a standard part of cardiac imaging evaluation. Intermodality comparisons are useful in determining whether modalities are interchangeable. Multidetector Computed tomography (CT) and single photon emission CT (SPECT) myocardial perfusion imaging (MPI) have been compared in only a few cohorts. We compared these modalities in a sex-balanced group. MATERIALS AND METHODS: Sixty outpatients (30 women 30 men) referred for MPI underwent CT on the same day. We calculated LVEF, end-diastolic volume (EDV), and end-systolic volume (ESV) from CT and MPI datasets using a commercially available, semi-automated routine and quantitative gated SPECT (QGS) respectively. Correlations, t-tests and Bland-Altman plots were performed for ESV, EDV, and LVEF. Bivariate and multiple regression analyses for LVEF were performed for both modalities. The subgroups for men and women were analyzed. RESULTS: Computed tomography showed moderate to high correlations with SPECT for LVEF (0.62), EDV (0.70), and ESV (0.63). End-diastolic volume and LVEF were significantly higher on CT as compared to SPECT (P < 0.001 each). Multiple regression analysis showed a significant relationship between sex and LVEF (P < 0.0001) on SPECT but not on CT. In men, there were significantly higher EDV (P = 0.014) and LVEF (P < 0.001) on CT compared with SPECT, but there was no difference in ESV. For women, there were significantly higher EDV and ESV on CT (P < 0.001 each), but no difference in LVEF. CONCLUSIONS: Left ventricular volumes and LVEF differed significantly on CT compared with SPECT and varied according to sex. Therefore, left ventricular volumes and LVEF values on CT and SPECT are not interchangeable.

Variants and anomalies of thoracic vasculature on computed tomographic angiography in adults.

OBJECTIVE: To determine the prevalence and clinical significance of normal, variant, and anomalous branching patterns of the aortic arch and the central veins on computed tomographic (CT) angiography in adults. METHODS: We retrospectively reviewed 1000 consecutive CT angiograms of the chest in 658 women and 342 men with a median age of 53 years. RESULTS: A total of 65.9% of patients had both normal aortic arch branching patterns and normal venous anatomy. Variants in the aortic arch branching pattern were present in 32.4% and anomalies in 1.5%. Venous anomalies were present in 0.7%. Review of CT reports showed that cardiothoracic radiologists correctly reported the anomaly more frequently than other radiologists (94% vs 20%, P = 0.003). CONCLUSIONS: Whereas anomalies of the central thoracic vasculature are uncommon, variants in the aortic arch branching pattern are common. An appreciation of the appearance of these entities on CT angiography allows for precise reporting and is useful in preprocedure planning.

Demonstration of left ventricular outflow tract eccentricity by 64-slice multi-detector CT.

BACKGROUND: Newer three-dimensional imaging technologies provide insight into cardiac shape and geometry from views previously unobtainable. Standard formulae like the continuity equation (CE) that rely on inherent assumptions about left ventricular outflow tract (LVOT) shape may need to be revisited. In the CE, small changes in LVOT diameter may significantly change calculated aortic valve area (AVA). Using 64-slice Multi-detector CT (MDCT), we performed LVOT planimetry to obviate the need for any geometric assumptions. METHODS: 64-slice MDCT was performed in 30 consecutive patients. The diameter-derived LVOT area (ALVOTdiam) was calculated from a view analogous to the 2D echo parasternal long axis. Direct planimetry of the LVOT (ALVOTplan) was performed just beneath the aortic valve in a plane perpendicular to the LVOT long axis. Further, assuming an ellipsoid outflow tract shape, LVOT area (ALVOTellip) was calculated using piab from the long and short diameters of the planimetered LVOT view. Eccentricity index (EI) was estimated by subtracting the ratio of shortest and longest LVOT diameters from one. RESULTS: ALVOTdiam always measured smaller than ALVOTplan (mean 3.7 +/- 1.2 cm2 vs. 4.1 +/- 1.3 cm2, respectively). The median EI was 0.18 (95% CI = 0.16-0.2; P = 0.0001). ALVOTellip more closely agreed with ALVOTplan (correlation = 0.96; P < 0.0001) than did ALVOTdiam (correlation = 0.87; P < 0.0001). CONCLUSION: Using MDCT, the LVOT was shown to be elliptical in most patients. Applying the CE which assumes roundness of the LVOT consistently underestimated the LVOT area which may affect estimated AVA. Planimetry of the LVOT utilizing three-dimensional imaging modalities such as 3-D echocardiography, MRI, or MDCT may render a more precise AVA.