Comparison of respiratory motion artifact from craniocaudal versus caudocranial scanning with 64-MDCT pulmonary angiography.

OBJECTIVE: The purpose of this article is to compare respiratory motion artifact between craniocaudal versus caudocranial 64-MDCT acquisition for CT pulmonary angiography. MATERIALS AND METHODS: We retrospectively reviewed 100 consecutive emergency radiology CT pulmonary angiography examinations acquired on a 64-MDCT scanner between April 2007 and February 2008 for two groups of patients: caudocranial acquisition (mean age, 50.5 years; range, 16.6-84.2 years; mean [+/- SD] scan duration, 9.1 +/- 1.1 seconds) and craniocaudal acquisition (mean age, 56.5 years; range, 22.4-94.2 years; mean scan duration, 7.1 +/- 0.9 seconds). Two blinded readers reviewed randomized coronal reformatted images in lung windows and scored the severity of respiratory motion artifact in the upper, middle, and lower lung zones on a 4-point scale (0, no artifact; 1, mild; 2, moderate; and 3, severe). Caudocranial versus craniocaudal differences in artifact severity were assessed using the concordance statistic. The Student's t test was used to compare incidence of diagnostically limited examinations containing moderate or severe artifact. RESULTS: There were no statistically significant differences between scans obtained in the caudocranial versus craniocaudal scan direction in any lung zone or on the basis of the most severe artifact score per patient (p > 0.3). There were no significant differences between the groups with regard to the incidence of diagnostically limited scans (p > 0.25) containing either moderate or severe artifact. CONCLUSION: Craniocaudal CT pulmonary angiography multislice acquisition with a slight decrease in scan duration had a similar degree of respiratory motion artifact to caudocranial scanning, performing equivalently in all lung zones and on an overall patient-by-patient basis.

Nonoperative management of patients with a diagnosis of high-grade small bowel obstruction by computed tomography.

OBJECTIVE: To determine the natural history and treatment of high-grade small bowel obstruction (HGSBO). Small bowel obstruction is a frequent complication of abdominal surgery. Complete and strangulating obstructions are managed operatively while partial obstructions receive a trial of nonoperative therapy. The management and outcome of patients with HGSBO diagnosed by computed tomography (CT) has not been examined. DESIGN: Retrospective medical record review. Outcomes for nonoperative vs operative management were analyzed using Fisher exact and log-rank tests. SETTING: Tertiary care referral center. PATIENTS: One thousand five hundred sixty-eight consecutive patients admitted from the emergency department with a diagnosis of small bowel obstruction between 2000 and 2005 by CT criteria. MAIN OUTCOME MEASURES: Recurrence of symptoms and complications. RESULTS: One hundred forty-five patients (9%) with HGSBO were identified, with 88% follow-up (median, 332 days; range, 4-2067 days). Sixty-six (46%) were successfully managed nonoperatively while 79 (54%) required an operation. Length of stay and complications were significantly increased in the operative group (4.7 days vs 10.8 days and 3% vs 23%; P < .001). Nonoperative management was associated with a higher recurrence rate (24% vs 9%; P < .005) and shorter time to recurrence (39 days vs 105 days; P < .005) compared with operative intervention. Computed tomography signs of ischemia, admission laboratory results, and presence of cancer or inflammatory bowel disease were not predictive of an operation. CONCLUSIONS: Patients with HGSBO by CT can be managed safely with nonoperative therapy; however, they have a significantly higher rate of recurrence requiring readmission or operation within 5 years.

Renal venous diversion: an unusual treatment for renal vein thrombosis.

Renal venous thrombosis most commonly occurs in the setting of nephrotic syndrome, hypercoagulability, or dehydration. This can usually be treated with systemic anticoagulation, and the diversion is via natural draining tributaries, eg, adrenal, lumbar, or gonadal veins. Occasionally, renal venous thrombosis results from extension of a thrombotic process, such as a large renal cell carcinoma with tumor thrombus extension into the infrahepatic inferior vena cava resulting in thrombosis of the inferior vena cava and contralateral renal vein. Herein, we report a case of left renal vein thrombosis relieved by diversion through the inferior mesenteric vein.

Atlantoaxial instability associated with an orthotopic os odontoideum: a multimodality imaging assessment.

Radiography, computed tomography (CT), and magnetic resonance imaging exams of the cervical spine were performed in a 29-year-old man who was ultimately diagnosed with an orthotopic os odontoideum during admission for injuries sustained in a motor vehicle collision. Initial radiography suggested either os odontoideum or an acute fracture of the dens. Further imaging with CT and flexion and extension radiographs confirmed os odontoideum and excluded a dens fracture. Although rare, os odontoideum is an important cervical spine anomaly to consider and to distinguish from an acute fracture of the dens.