Incidental bilateral accessory middle cerebral arteries on MR imaging and MR angiography.

Intracranial vascular variations involving the middle cerebral artery are rarely seen. Herein, we report an 11-year-old girl with incidental bilateral accessory middle cerebral arteries, an extremely rare variation, which is the first case in the related literature demonstrated by cranial magnetic resonance imaging and magnetic resonance angiography.

Unilateral perirenal fibrosis.

A case of multifocal fibrosclerosis with an extremely unusual unilateral perirenal involvement is reported. Computed tomography and magnetic resonance imaging findings of unilateral perirenal fibrosis are discussed.