Traumatic Thoracic Injury: The Role of Multidetector-row CT

The introduction of Multidetector-row CT (MDCT) has revolutionized the diagnostic strategy of multitrauma patients. The rapid acquisition of a large scanning volume with a thin slice collimation allows for motion-free images of high spatial resolution, and this enables the application of the multiplanar reformat (MPR) and 3D volume-rendering (VR) images. The MPR images more accurately demonstrate aortic rupture or dissection, diaphragmatic injuries and fracture of vertebrae, sternum and costal cartilages. Diagnosing vascular injuries can be aided by using the MIP images. Rib fracture, trachea and bronchial laceration are more easily detected by the 3D images, while airway and vascular injuries can be detected from performing virtual endoscopy. We introduce our current CT imaging protocol and we present our clinical experience with using MDCT in the assessment of patients with blunt thoracic trauma

Volumetric Measurements of Lung Nodules with Multi-Detector Row CT: Effect of Changes in Lung Volume

OBJECTIVE: To evaluate how changes in lung volume affect volumetric measurements of lung nodules using a multi-detector row CT. MATERIALS AND METHODS: Ten subjects with asthma or chronic bronchitis who had one or more lung nodules were included. For each subject, two sets of CT images were obtained at inspiration and at expiration. A total of 33 nodules (23 nodules > or = 3 mm) were identified and their volume measured using a semiautomatic volume measurement program. Differences between nodule volume on inspiration and expiration were compared using the paired t-test. Percent differences, between on inspiration and expiration, in nodule attenuation, total lung volume, whole lung attenuation, and regional lung attenuation, were computed and compared with percent difference in nodule volume determined by linear correlation analysis. RESULTS: The difference in nodule volume observed between inspiration and expiration was significant (p or = 3 mm. The volume of nodules was measured to be larger on expiration CT than on inspiration CT (28 out of 33 nodules; 19 out of 23 nodules > or = 3 mm). A statistically significant correlation was found between the percent difference of lung nodule volume and lung volume or regional lung attenuation (p or = 3 mm. CONCLUSION: Volumetric measurements of pulmonary nodules were significantly affected by changes in lung volume. The variability in this respiration-related measurement should be considered to determine whether growth has occurred in a lung nodule.

Multi-Slice Spiral CT of Living-Related Liver Transplantation in Children: Pictorial Essay

In pediatric living-related liver transplantation, preoperative evaluation of the recipient is important for surgical planning, while the accurate diagnosis of postoperative complications is essential for graft salvage. Multiplanar and three-dimensional imaging using multi-slice spiral CT can be used for preoperative vascular imaging, as well as for evaluating postoperative complications. In this essay, we describe the usefulness of multi-slice CT, combined with a variety of different reconstruction techniques, for the preoperative evaluation of transplant recipients. In addition, we demonstrate the multi-slice CT findings of postoperative complications, including vascular stenosis or thrombosis, bile duct leak or stricture, and extrahepatic fluid collection.

Diagnosis of Annular Pancreas Using Minimum Intensity Projection of Multidetector Row CT: Case Report

Annular pancreas is a rare congenital abnormality characterized by a ring of pancreatic tissue encircling the second portion of the duodenum, and it is definitively diagnosed by endoscopic retrograde cholangiopancreatography. We present here a case of annular pancreas that was diagnosed by the minimum intensity projection technique of multidetector row CT. On the CT scan, the annular pancreas was demonstrated as the pancreatic tissue with an aberrant pancreatic duct encircling the duodenum.

The Usefulness of Multiplanar Reconstruction Images in Preoperative T-staging of Advanced Gastric Cancer

PURPOSE: The purpose of this study was to evaluate the performance of multidetector-row CT (MDCT) in the preoperative T-staging of patients with advanced gastric cancer. MATERIALS AND METHODS: A total of 65 patients with an established diagnosis of advanced gastric cancer (T2 or more) were evaluated with MDCT. The protocol of MDCT consisted of high-quality (HQ) mode helical scanning with a slice thickness of 2.5 mm. The axial CT images were reconstructed with a slice thickness of 5 mm. MPR images were reconstructed from the raw axial data with a slice thickness of 5 mm. A comparison between the standard axial and axial MPR images was performed by two radiologists with regard to the evaluation of the tumor location and T-stage. These findings were compared with the pathologic and surgical findings. RESULTS: T-staging of the advanced stomach cancer was correct in 89% (58/65) and 69% (45/65) of the MPR images and axial images, respectively. The MPR images improved the detection rate (5 lesions)of the tumors and increased the accuracy of the T-staging (13 lesions) in comparison with the axial images. The MPR images are of greater diagnostic value for the evaluation of omental seeding (5 lesions: axial images, 9 lesions: MPR images), tumor location and extension. CONCLUSION: Multiplanar reconstruction (MPR) images provide increased confidence in the location and T-staging of certain cases of advanced gastric cancer, such as those in locations where CT images are susceptible to be affected by the difficulties associated with partial volume averaging. In this study, the MPR images provided more precise information about the tumor location and T-staging than the standard axial images in the preoperative evaluation of advanced gastric cancer.

Usefulness of Air as Oral Contrast Material at CT Examination in Patient with Post-Operative Gastric Cancer

PURPOSE: To evaluate the usefulness of multidetector-row CT (MDCT) with gastric luminal distention using effervescent granules in patients with previous subtotal gastrectomy for the evaluation of the stomach, anastomotic site and jejunum, and to compare its findings with those of spiral CT using oral contrast media in the same patients. MATERIALS AND METHODS: Thirty-one patients (M:F=25:6, mean age; 58 years) with previous subtotal gastrectomy, who underwent both spiral CT using oral contrast media and MDCT using effervescent granules, were studied. The distensibility of the gastric lumen, anastomotic site and jejunal lumen was graded as either poor, fair or good. The thickening or mass of the gastric and small bowel wall was also evaluated. RESULTS: The distensibility of the gastric lumen, anastomotic site and jejunal lumen were better demonstrated by MDCT using effervescent granules than by spiral CT using an oral contrast agent (p<0.05). The distensibility of the stomach and jejunum was similar in 14 cases (45.2%) on spiral CT and 16 cases (51.6%) on MDCT. The anastomotic site was better demonstrated when effervescent granules were used than when oral contrast media was used in 21 cases (67.7%). No cases of poor distention of the stomach or anastomotic site were detected when using effervescent granules. CONCLUSION: Follow-up MDCT using effervescent granules showed better distensibility of the gastric lumen, anastomotic site and jejunal lumen than spiral CT using oral contrast media in all of the patients having undergone subtotal gastrectomy.

Mediastinal and Hilar Lymphadenopathy: Cross-Referenced Anatomy on Axial and Coronal Images Displayed by Using Multi-detector row CT

The accurate evaluation of mediastinal and pulmonary hilar lymphadenopathy, especially in patients with lung cancer, is important for determining treatment options and evaluating the response to therapy. To indicate nodal location in detail, mediastinal and hilar lymph nodes have been assigned to one of 14 nodal stations. Mediastinal nodes of greater than 10 mm short-axis diameter are regarded as abnormal, irrespective of their nodal station, while hilar nodes are considered abnormal if their diameter is greater than 10 mm in any axis or they are convex compared to surrounding lung. By providing multiplanar images, multi-detector row CT allows detailed evaluation of thoracic anatomic structures more easily than in the past, when axial images only were available. At cross-referenced imaging, a lymph node depicted at axial imaging in one anatomical location can be visualized simultaneously and automatically at coronal imaging at the exactly corresponding anatomical location. Cross-referenced coincidental axial and coronal images help assess both the size and morphology of mediastinal and hilar lymph nodes.