Standard Multidetector Computed Tomography Research Articles

Detection of coronary calcium during standard chest computed tomography correlates with multi-detector computed tomography coronary artery calcium score

The correlation between formal coronary artery calcium scoring (CACS) determined by multi-detector CT (MDCT) and the presence of coronary calcium on standard non-gated CT chest examinations was evaluated. In 163 consecutive healthy participants, we performed screening same-day standard non-gated, non-enhanced CT chest exams followed by high-resolution, ECG-synchronized MDCT exams for CACS. For the standard CT examinations, a scoring system (Weston score, range 0-12) was developed assigning a score (0-3) for each coronary vessel including the left main trunk. Overall, 30% and 39% of patients had CAC on standard CT and MDCT exams, respectively (P = 0.13). CAC on standard CT was highly correlated to the Agatston CACS on the MDCT (Spearman correlation coefficient 0.83, P < 0.001). Absence of calcium on the standard CT exam was associated with a very low CACS (mean Agatston 0.5, range 0-19). A Weston score >2 identified a CACS > 100 with an area under the curve of 0.976, sensitivity of 100%, and specificity of 85%. A Weston score >7 identified a CACS > 400 with an area under the curve of 0.991, sensitivity of 100%, specificity of 98%. The intra-observer variability was low as was the inter-observer variability between a cardiac specialized radiologist and a non-specialized reader. A visual coronary artery scoring system on standard, non-gated CT correlates well with traditional methods for CACS. Further, a non-expert cardiac radiologist performed equally well to a cardiac expert. This information suggests that a visual scoring system, at least in a descriptive manner can be utilized for a general statement about coronary artery calcification seen on standard CT imaging to guide clinicians in risk stratification.

Significance of sagittal reformations in routine thoracic and abdominal multislice CT studies for detecting osteoporotic fractures and other spine abnormalities

The purpose was to assess osteoporotic vertebral fractures and other spinal lesions in sagittal reformations obtained from routine multidetector computed tomography (MDCT) studies of the thorax and abdomen, to compare sagittal reformations with axial images in detecting these lesions and to investigate how frequently they were missed in the official radiology report. Routine abdominal or thoracoabdominal MDCT using a standard protocol was performed in 112 postmenopausal women. Axial images and sagittal reformations were analyzed separately by two radiologists in consensus and were compared in order to evaluate how often spinal lesions could be detected. In addition the official radiology reports were assessed to determine how many of those abnormalities were identified. Spine abnormalities were visualized in 101/112 postmenopausal women. In 27 patients osteoporotic vertebral deformities were found; 6 of these were shown in the axial images, but none of these were diagnosed in the official radiology report. Additional abnormalities included degenerative disc disease, osteoarthritis of the facet joints, scoliosis, hemangiomas and bone metastases. In only 9/101 patients spine abnormalities were mentioned in the radiology report. Sagittal reformations of standard MDCT images provide important additional information on spinal abnormalities; in particular, osteoporotic vertebral deformities are substantially better detected.

Acute pulmonary embolism: Comparison of standard axial MDCT with paddlewheel technique

Purpose The purpose of this study was to evaluate the ability of rotated paddlewheel reformations for the detection of central and peripheral pulmonary embolism (PE) compared to standard axial multi detector CT (MDCT) images. Material and methods CT scans of 35 patients with PE were reviewed by three independent readers for the detection of pulmonary emboli using standard axial CT scans and reformatted paddlewheel technique. All images were evaluated in random order. MDCT examinations were performed with a collimation of 1.25 mm, a pitch of six and a reconstruction interval of 0.8 mm. For each patient MIP were reformatted by using a paddlewheel arrangement with 5 mm slab thickness and 5° rotation. Standard of reference for PE was a consensus reading of the axial images by all three readers. Results The overall sensitivity for the axial images for the three readers ranged between 91% and 96%; for paddlewheel reformations from 78% to 83%; the specificity for both methods was 98–99%. Inter- and intraobserver agreement was also higher for axial images than for paddlewheel reformations. Conclusion Comparing standard axial MDCT scans and reformatted paddlewheel images no significant difference for the detection of central PE was found, whereas for the detection of peripheral emboli standard axial images showed a significant higher percentage of detecting PE than paddlewheel reformations.