Assessment of intraocular foreign bodies by helical-CT multiplanar imaging.

The aim of this study was to examine the effectiveness of helical CT in the assessment of intraocular foreign bodies, evaluating two protocols with different collimation. We performed helical-CT studies in 30 patients. Fifteen patients were examined with 1.5-mm collimation and the other 15 patients with 3.0-mm collimation. All other imaging parameters were identical in both protocols. Multiplanar images were reconstructed. The examinations were reviewed for presence, localization and size of intraocular foreign bodies. We compare our results with the surgical data. We estimate the required examination time. In the first group (collimation 1.5 mm) an intraorbital foreign body was detected in 8 of 15 patients. In 3 of 8 patients an intraocular foreign body (all were metallic) was detected. In the second group (collimation 3.0 mm) an intraorbital foreign body was detected in 9 of 15 patients. In 8 of 9 patients an intraocular foreign body (all were metallic) was detected. Our results were confirmed by surgery in all cases. Examination time was 36 s in the first group and 18 s in the second group. Computed tomography should be considered the imaging modality of choice in the assessment of metallic intraocular foreign bodies and 3.0-mm collimation is optional, because of reduced examination time and radiation exposure.

Perforation of the alimentary tract: evaluation with computed tomography.

BACKGROUND: To assess the value of computed tomography (CT) in the diagnosis of perforation of the alimentary tract (AT). METHODS: During a 4-year period 76 patients with proven AT perforation underwent CT within 1 week before surgery or endoscopy. We retrospectively reviewed these CT scans to determine the signs of AT perforation. There were 41 men and 35 women (28-90 years old). Our goal was to establish the diagnosis of AT perforation and, if this was possible, to identify the site and cause of the AT wall rupture. The CT diagnosis of perforation was based on (a) direct findings of extraluminar air or gastrografin and (b) indirect findings of an abscess or an inflammatory mass surrounding an enterolith in the region of appendix or a bowel wall-related phlegmon or abscess with fluid in the mesentery or surrounding radiopaque foreign body. RESULTS: There were 65 true-positive and 11 false-negative cases. Levels of perforation were the esophagus (two), stomach (five), duodenum (12), small bowel (15), appendix (six), and colon (36). Causes were peptic ulcer (11), foreign body (five), trauma (seven), iatrogenic (nine), appendicitis (six), diverticulitis (21), Crohn disease (five), AT carcinoma (eight), and ischemia (four). Level and cause were correctly predicted in 55 and 51 instances, respectively. The sensitivity was estimated to 85.5%. CONCLUSION: CT is a valuable method in the diagnosis of AT perforation. The diagnosis can be established rapidly, without patient preparation and with a high sensitivity.