Value of spiral CT in the early diagnosis of renal infarction.

Introduction: Renal infarction is a rare and often difficult diagnosis. The objective of this study was to demonstrate that contrast-enhanced spiral C T in patients presenting features of renal colic, can establish the diagnos is by confirming the presence of infarction of the renal parenchyma. Material and Methods: Over a 10-month period, the authors proposed the foll owing decision flow-chart for all patients admitted with clinical features of renal colic: plain abdominal x-ray and first-line renal ultrasound, whic h, in the absence of a diagnosis (stones or dilation of cavities), were com pleted by unenhanced spiral CT scan. When these examinations were normal, c ontrast-enhanced spiral CT scan was then performed. Results: 300 patients were included in this study, and CT was performed in 40 cases. This management allowed the diagnosis of infarction of the renal parenchyma in three patients, who are described here. When unenhanced CT se ctions do not reveal any abnormality, contrast-enhanced sections are essent ial to visualize the infarct zone, seen as a triangular low density lesion with clearly defined margins and a vascular topography. Conclusion: Contrast-enhanced spiral CT should now be considered to be the reference examination for the assessment of non-documented renal colic. Thi s recent imaging modality should allow the diagnosis of a greater number of infarctions of the renal parenchyma, which formerly remained undiagnosed.