Evaluating diabetic foot infection with magnetic resonance imaging: Kuwait experience.

OBJECTIVE: The aim of this study was to evaluate the capability of magnetic resonance imaging (MRI) to depict and characterize the changes seen in diabetic foot infections. SUBJECTS AND METHODS: MRI studies of 29 diabetic patients with suspected foot infection were evaluated. Sagittal and transverse T1-weighted images before and after intravenous gadolinium, and transverse fat-suppressed T2-weighted images were performed on the affected regions. The MRI findings were compared to subsequent clinical and/or histopathological findings. RESULTS: The MRI findings were: osteomyelitis in 14 patients, abscess in 5, cellulitis in 26, tenosynovitis in 4 and neuropathic joint in 8. Three cases were normal. Pathological confirmations were obtained in 19 patients. MRI and histological diagnosis were in concordance in 79% of osteomyelitis cases, 100% of neuropathy cases and 100% of cellulitis cases. The sensitivity and specificity of MRI in diagnosing osteomyelitis were 100 and 63%, respectively. The positive predictive and negative predictive values, and the accuracy were 79, 100 and 84%, respectively. MRI helped surgical planning for limb salvage procedures in 6 of the osteomyelitis cases and in a cellulitis case. CONCLUSION: The results indicate that MRI is a sensitive and accurate imaging modality for the evaluation of foot infections in diabetic patients and for planning proper treatment.

Contrast media extravasation: manual versus power injector.

OBJECTIVE: To compare the incidence and complications of extravasation of low-osmolar nonionic contrast media, injected manually and by the automatic power injector (API). SUBJECTS AND METHODS: Three thousand five hundred and sixty patients underwent contrast-enhanced abdominal and thoracic computerized tomography scan in the Department of Clinical Radiology, Al-Amiri Hospital, Kuwait, between June 1998 and December 2002. These patients were prospectively analyzed for contrast media extravasation, its relation to injection rate, cannula insertion and gauge and its complications. 920 patients were administered low-osmolar nonionic contrast media (Ultravist 300, Omni Paque 240 or 300) intravenously by manual injection and 2,640 patients by automatic power injector. RESULTS: Of the 3,560 patients contrast media extravasation occurred in 11 (0.3%). The symptoms were observed in 9 patients (0.3%) in the API group and 2 patients (0.2%) in the manual injection group, respectively. None of the patients had any soft tissue injury. CONCLUSION: The incidence of contrast media extravasation is not significantly increased by the use of the API. Low-osmolar nonionic contrast media extravasation resulting from the use of API does not cause any morbidity.

Contrast-enhanced cranial computed tomography in magnetic resonance imaging era.

OBJECTIVE: To evaluate the usefulness of intravenous contrast administration in cranial computed tomography (CT) in a general hospital with a magnetic resonance imaging (MRI) facility, and to establish a protocol to determine which patients would benefit most from using contrast-enhanced cranial CT. SUBJECTS AND METHODS: Five hundred and forty-seven patients who underwent routine nonenhanced CT (NECT) and contrast-enhanced CT (CECT) of the brain between June 1997 and June 2001 were divided into three groups. Group A: 496 patients in whom CECT was done in spite of normal NECT; group B: 16 patients in whom CECT was considered necessary irrespective of NECT findings, and group C: 35 patients in whom NECT was abnormal and CECT was performed. RESULTS: Contrast-enhanced cranial CT changed and/or confirmed the diagnosis in 1 of 496 in group A, 2 of 16 in group B, and 12 of 35 in group C, thereby indicating that CECT was useful in the diagnosis of groups B and C. CONCLUSION: CECT is unlikely to be useful in patients with normal NECT in the appropriate clinical setting. A protocol is presented for the use of contrast media in cranial CT in a general hospital with an MRI facility. Using this protocol only 9.7% of patients for cranial CT would have needed CECT, resulting in considerable cost savings without affecting the quality of the service to the patient in a general hospital.