Positron emission tomography in the investigation of pediatric inflammatory bowel disease.

BACKGROUND: Endoscopic and radiologic studies are frequently required in inflammatory bowel disease (IBD) to determine disease activity, extent of disease, and delineating disease type. Positron emission tomography (PET) using fluorine-18-fluoro-deoxyglucose to identify metabolically active tissues may offer a simple noninvasive alternative to conventional studies in identification and localization of active intestinal inflammation in children with IBD. The aim of this study was to assess the value of PET in identifying active intestinal inflammation compared with conventional endoscopic and radiologic studies, including small bowel follow-through and colonoscopy. METHODS: Sixty-five children were enrolled in the study. This included 55 children (mean age, 13.3 yr; range, 7-18 yr; 20 girls) with newly diagnosed IBD (37) or symptoms suggestive of recurrent disease (18) and 10 children with recurrent abdominal pain (mean age, 12.7 yr; range, 8-15 yr; 7 girls) who were studied with PET, and the results were compared with small bowel follow-through with pneumocolon and/or colonoscopy. Thirty-eight patients had Crohn's disease (17 ileal, 12 ileocolic, 5 pancolonic, 3 left-sided disease, 1 right-sided disease), and 17 had ulcerative colitis (15 pan-colitis, 2 left-sided colitis). Mean time interval between PET and other studies was 30 +/- 17.6 days. RESULTS: PET correctly identified active inflammatory disease in 80% of children with IBD (81.5% with Crohn's disease; 76.4% with ulcerative colitis) and correctly showed no evidence of inflammation in children with recurrent abdominal pain. Gluorine-18-fluoro-deoxyglucose accumulated at sites that corresponded with active disease at colonoscopy in 83.8% of patients and with small bowel follow-through with pneumocolon 75.0% of the time. CONCLUSION: This study suggests that PET offers a noninvasive tool for identifying and localizing active intestinal inflammation in children with IBD. PET may not be able to replace conventional studies; however, it may be useful when conventional studies cannot be performed or fail to be completed.

Testicular torsion revisited.

Ultrasound is routinely used for the assessment and diagnosis of testicular torsion. It has proven to be a reliable and necessary diagnostic tool for the urologist. Problems, however, can arise in the form of misdiagnosis when the basic pathophysiology and clinical presentation of testicular torsion are not clearly understood. In this pictorial review, we present the spectrum of the appearance of testes with testicular torsion. This includes both complete and incomplete torsion. The critical use of Doppler and the interpretation of the Doppler findings will be presented. Other abnormalities that can be potentially confused with testicular torsion, including epididymitis and orchitis, will be shown. An approach to assessing the testis that stresses the critical role of both Doppler examination and an understanding of the clinical presentation will be presented. In particular, in incomplete torsion, a Doppler examination will still demonstrate flow to the testis, potentially leading to a missed diagnosis if the clinical presentation is not considered. Examples of normal and abnormal anatomy will be presented.

Ultrasound of the carotid arteries: a pictorial review.

Stroke secondary to atherosclerotic disease remains one of the leading causes of death. Ischemia from severe, flow limiting stenosis due to atherosclerotic disease involving the extracranial carotid arteries is implicated in approximately 20-30% of strokes. An estimated 80% of strokes are thromboembolic in origin, often with carotid plaque as the embolic source, usually involving the internal carotid artery within 2 cm of the carotid bifurcation. Carotid endarterectomy has been proven to be more beneficial than medical therapy in symptomatic patients with greater than 70% stenosis. Accurate diagnosis of hemodynamically significant stenosis is therefore critical in identifying those patients who would benefit from the surgery. In this paper we present a pictorial review of the use of ultrasound in the examination of the carotid arteries.

Accuracy of Doppler echocardiography for the diagnosis of thrombosis associated with umbilical venous catheters.

We conducted a prospective cohort study to determine the incidence of asymptomatic thrombosis associated with an indwelling umbilical venous catheter (UVC) and to evaluate the diagnostic accuracy of Doppler echocardiography compared with contrast venography. The mean birth weight (SD) of the 47 eligible infants was 1962 (1101.5) g, and the mean gestational age (SD) was 32.2 (5.4) weeks. Catheters remained in situ for a mean (SD) of 7.0 (2.3) days. Thrombi were detected by venogram in 14 cases (30%). The accuracy of the echocardiographic diagnoses was poor, with sensitivities of 21%, 43%, and 21%, respectively, for the 3 cardiologists. Corresponding specificities were 91%, 76%, and 94%. We conclude that asymptomatic thrombosis is common in sick newborn infants with UVCs. Contrast venography is required to accurately diagnose such thrombi in affected patients.