3D imaging with an isocentric mobile C-arm comparison of image quality with spiral CT.

The purpose of this study was to evaluate the image quality of the new 3D imaging system (ISO-C-3D) for osteosyntheses of tibial condylar fractures in comparison with spiral CT (CT). Sixteen human cadaveric knees were examined with a C-arm 3D imaging system and spiral computed tomography. Various screws and plates of steel and titanium were used for osteosynthesis in these specimens. Image quality and clinical value of multiplanar (MP) reformatting of both methods were analyzed. In addition, five patients with tibial condylar fractures were examined for diagnosis and intra-operative control. The image quality of the C-arm 3D imaging system in the cadaveric study was rated as significantly worse than that of spiral CT with and without prostheses. After implantation of prostheses an increased incidence of artifacts was observed, but the diagnostic accuracy was not affected. Titanium implants caused the smallest number of artifacts. The image quality of ISO-C is inferior to CT, and metal artifacts were more prominent, but the clinical value was equal. ISO-C-3D can be useful in planning operative reconstructions and can verify the reconstruction of articular surfaces and the position of implants with diagnostic image quality.

A case of an upper gastrointestinal bleeding due to a ruptured dissection of a right aortic arch.

We report a case of severe upper gastrointestinal hemorrhage with a rare underlying cause. The patient was unconscious when he was admitted to the hospital. No chest radiogram was performed. Routine diagnostic measures, including endoscopy, failed to reveal the origin of the bleeding, which was believed to originate from the esophagus secondary to a peptic ulcer or varices. Exploratory laparotomy added no further information, but contrast-enhanced multislice computed tomography (MSCT) of the chest showed dextroposition of the widened aortic arch with a ruptured type-B dissection and a consecutive aorto-esophageal fistula (AEF). The patient died on the day of admission. Noninvasive MSCT angiography gives rapid diagnostic information on patients with occult upper gastrointestinal bleeding and should be considered before more invasive conventional angiography or surgery.

Whole-body computed tomography in polytrauma: techniques and management.

An interdisciplinary team should be involved in the diagnosis and management of severely injured patients. The adoption of criteria for starting treatment for multiple trauma avoids underestimation of seriousness of injury. These criteria are established by the circumstances of the accident, the patterns of trauma, and the vital findings. Basic diagnosis comprises a limited number of plain films in the trauma room, including supine chest, lateral cervical spine, and pelvis, and ultrasound of abdomen, pleura, and pericardium. Organ diagnosis using CT is complementary and depends on the clinical findings and findings from the basic investigations. We recommend spiral CT (skull base 2/2/4 mm, cerebrum 8/8/8 mm native) and after intravenous contrast medium thoracic (5/7.5/5 mm) and abdominal CT (8/12/8 mm). Image reconstruction of bony structures can be added. The CT and the trauma center should be in close proximity; time-consuming transfers must be avoided. If this is not possible, a CT can be integrated in the trauma room. Our hospital trauma registry contains over 2200 entries. A quality committee has been established and external quality control is implemented.

Three-dimensional CT with a modified C-arm image intensifier: feasibility.

A portable C arm was modified for cone-beam computed tomography (CT). This three-dimensional (3D) CT imaging system facilitated the acquisition of fluoroscopic images during a 190 degrees rotation and computed a 3D data cube (matrix, 256 x 256 x 256; scanning time, 100 seconds) with multiplanar image reformation. The high-contrast resolution, 0.9 line pairs per millimeter, was comparable; the low-contrast resolution, minimal; and the radiation dose, 60%-80% lower, as compared with these parameters at spiral CT. The normal anatomy of small joints could be depicted, and the osteosynthesis screws in the talus were correctly identified.