Operative time analysis of miniplate fixation of the mandible

Our purpose in this study was to report and compare operating room times for the various methods of mandible fracture repair. We describe a methodology of treatment in selected patients, using efficient repair techniques; namely, miniplate fixation with four-screw mandibular occlusion. We report our outcomes in successful healing, occlusion, complications, and operating times. A retrospective chart review was performed of 68 patients suffering mandible fractures treated by various surgeons at a single institution. Miniplate fixation technique requires significantly less time in the operating room than other mandible repair techniques, including mandibulomaxillary fixation. Miniplate fixation technique is both an efficacious and an efficient means of repairing certain mandible fractures.     

Rectal cancer masquerading as an amoeboma: case report and review of the literature

Despite the prevalence of amoebiasis in many parts of the world, amoebomas are relatively uncommon. Amoebomas within the colorectum are indistinguishable from carcinomas either macroscopically or by barium enema examination and the presence of both conditions is much rarer still. Herein, we describe such a case and review the possible reasons for their coexistence.     

Is there a learning curve in diagnosing urolithiasis with noncontrast helical computed tomography?

OBJECTIVE: To report one department's experience with helical computed tomographic (HCT) evaluation of patients with suspected renal colic to diagnose ureteral calculi; to determine whether there is a learning curve in performing HCT in this context; and to determine whether HCT for the evaluation of renal colic exposes patients to more radiation than the standard intravenous pyelography (IVP) combined with nephrotomography. METHODS: All patients presenting to the emergency department with flank or abdominal pain were evaluated with nonreformatted noncontrast HCT. To determine changes in diagnostic accuracy, patients were divided into 2 groups: those evaluated between September 1996 and January 1997 (group 1, 67 patients), and those seen from February to June 1997 (group 2, 53 patients). A radiation exposure study was performed using phantoms, and radiation exposure for HCT, IVP and nephrotomography was measured. RESULTS: Review of HCT scans to diagnose ureteral calculi had a sensitivity of 91.7%, specificity of 82.6%, and accuracy of 87.2% in group 1, and a sensitivity of 95.5%, specificity of 86.7%, and accuracy of 91.9% in group 2. Patients undergoing IVP with nephrotomography were exposed to an effective dose equivalent of 343 mrem (dSv) (for men) and 664 mrem (for women). The effective dose equivalent for an HCT scan was 180 mrem. CONCLUSION: HCT offers excellent, rapid diagnostic accuracy without the need for intravenous contrast medium and with a lower radiation exposure level than IVP in evaluating patients with acute flank pain. There is a small but real learning curve in evaluating patients with acute flank pain with HCT.     

Interobserver variation in the interpretation of abdominal radiographs

A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.     

Effect of intersection spacing on MR image contrast and study time

The effects of section separation on image contrast and calculated T1 relaxation times were investigated in healthy volunteers and a phantom using an early commercial version magnetic resonance imaging system. The effects are explained qualitatively on the basis of side lobes of excitation occurring outside the selected section resulting in reduction of the time permitted for T1 relaxation. The options for dealing with imperfect section selection, including separation of the sections (i.e., leaving gaps) and nonsequential excitation, are illustrated and the trade-offs involved in each explained.     

Perforation of the inferior vena cava with aortic and vertebral penetration by a suprarenal Greenfield filter

Various complications have been reported after insertion of the Greenfield filter. This report describes an unusual complication after suprarenal placement of this filter: spreading of the filter struts, with perforation of the inferior vena cava, and penetration of the aorta and a vertebral body, followed by fracture of one of the struts.     

High-resolution MR imaging with local coils

We propose the following rules to govern the choice of local coils by the practicing radiologist: 1. Smaller coils permit smaller FOVs and better resolution. The coil should be as small as possible. 2. Match the ROS of the coil to the FOV, which will be determined by the anatomic region of interest. 3. For the case of a choice between surface coils or between a surface and a whole- or partial-volume coil, the anatomic region should lie on the high side of the crossover point. For the case of a choice among whole-volume coils, the smallest coil that surrounds the region of interest should be chosen. 4. Considerations in regard to the anatomic shape or the need to vary the position of the structure may alter the choice of coil from that obtained by S/N considerations alone.