Spoke wheel sign (meningioma)
The spoke wheel sign refers to the pattern of vessels coursing through meningiomas, when seen in cross-section. It is the result of the same phenomenon which results in the sunburst pattern (vessels seen from the side rather than in cross section).
Renal oncocytomas are benign, solid tumours of the kidney. An angiographic spoke-wheel pattern is known to be associated with oncocytomas, although it is not pathognomonic. On review of the literature, we found two reports of sonographic spoke-wheel appearance in oncocytomas. These were sufficiently characteristic to enable a confident preoperative diagnosis of oncocytoma. We present a case of a surgically proven oncocytoma with a distinct helical CT appearance, -commensurate with the angiographic and sonographic spoke-wheel appearance from which the diagnosis was suspected preoperatively.