Assessment of the anterior spinal artery and the artery of Adamkiewicz using multi-detector CT angiography.

BACKGROUND: Damage to the spinal cord after the treatment of the descending thoracic and thoracoabdominal aortic aneurysms is an uncommon but devastating complication. The artery of Adamkiewicz (AKA) is the principal arterial supply of the anterior spinal artery (ASA) in the lower thoracic and lumbar level. The purpose of this study was to evaluate the visualization of the anterior spinal artery and the artery of Adamkiewicz, the affecting factors for the detection rate using multi-detector row CT (MDCT). METHODS: Ninety-nine consecutive patients (31 women and 68 men; age range, 25 - 90 years; average age 61.3 years), with suspicion for thoracic aortic lesions necessitating surgical intervention (31 aortic aneurysm, 45 dissection, 5 intramural hematoma, and 18 normal), underwent CT angiography from the aortic arch to the aortic bifurcation. Transverse sections, multiplanar reformations and thin maximum intensity projections were used to assess the ASA and AKA. The level of the ASA and AKA origins and CT acquisition parameters were recorded. The contrast-to-noise ratio of the image, an index of the mass of the T11 body (vertebral mass index), the subcutaneous fat thickness, and the CT value within the aortic arch and at the T11 level were measured. The detection of the ASA and AKA were evaluated relative to the acquisition parameters, scan characteristics, and aortic lesion type. Differences were assessed with the Wilcoxon rank-sum and t tests. RESULTS: The ASA was visualized in 51 patients (52%) and the AKA in 18 patients (18%). The ASA was identified in 36/67 patients (54%) with 1.25 mm thickness and in 15/32 patients (47%) with 2.5 - 3.0 mm thickness. This difference did not achieve significance (P = 0.13). The detection rate of the ASA and the AKA was influenced by the vertebral mass index and the contrast-to-noise ratio (P < 0.05). The amount of subcutaneous fat affected the detection rate of the ASA (P < 0.05) but not the AKA. In CT scans of ASA detection, the mean CT values in the aorta at the arch and at T11 were 360 and 358 HU, respectively, whereas in CT scans without ASA detection, the CT values in the aorta at the arch and at T11 were lower (P < 0.05), 297 and 317 HU, respectively. CONCLUSIONS: The ASA and AKA were less frequently detected in our cohort than previous reports. The visualization of the ASA and AKA was significantly affected by aortic enhancement, the "vertebral mass index", and the contrast-to-noise ratio.

Alternative input devices for efficient navigation of large CT angiography data sets.

PURPOSE: To compare devices for the task of navigating through large computed tomographic (CT) data sets at a picture archiving and communication system workstation. MATERIALS AND METHODS: The institutional review board approved this study, and all subjects provided informed consent. Five radiologists were asked to find 25 different vascular targets in three CT angiography data sets (average number of sections, 1025) by using several devices (trackball, tablet, jog-shuttle wheel, and mouse). For each trial, the total time to acquire the targets (T1) was recorded. A secondary study in which 13 nonradiologists performed seven trials with an artificial target inserted at a random location in the same image data was also performed. For each trial, the following items were recorded: time until first target sighting (t2), time to manipulate the device after seeing the target, sections traversed during t2 (d1), time from first sight to target acquisition (t4), sections traversed during t4 (d2), and total trial time. Statistical analysis involved repeated-measures analysis of variance (ANOVA) and pairwise comparisons. RESULTS: Repeated-measures ANOVA revealed that the device used had a significant (P < .05) effect on T1. Pairwise comparisons revealed that the trackball was significantly slower than the tablet (P < .05) and marginally slower than the jog-shuttle wheel (P < .10). Further repeated-measures ANOVA for each secondary outcome measure revealed significant differences between devices for all outcome measures (P < .005). Pairwise comparisons revealed the trackball to be significantly slower than the other devices in all measures (P < .05). The trackball was significantly (P < .05) more accurate than the other devices for d1 and d2. CONCLUSION: The trackball may not be the optimal device for navigation of large CT angiography data sets; the use of other existing devices may improve the efficiency of interpretation of these sets.

Stability of retrospective reports in depression: traumatic events, past depressive episodes, and parental psychopathology.

Research findings based on the retrospective reports of depressed individuals have long been held suspect because of possible negative reporting biases associated with depression. In the present study we assess the stability of retrospective reports of past traumatic events, past depressive episodes, parental depression, and parental substance abuse in a sample of 234 adults whose depression status changed over two assessments conducted one year apart. Depression status was found to affect reporting of number of past depressive episodes and past traumatic events, but not reporting of parental psychopathology. Implications of these findings are discussed for research that relies on the retrospective self-reports of depressed participants.