Hypertrophic olivary degeneration secondary to a Guillain Mollaret triangle cavernoma: Two case report.

Hypertrophic olivary degeneration (HOD) is a rare form of transsynaptic degeneration. It is caused by a damage at the Guillain-Mollaret triangle (GMT), which is defined by three anatomical structures: the dentate nucleus, the red nucleus, and the inferior olivary nucleus (ION). Clinically, it may be revealed by palatal myoclonus. On MRI, it appears as a unilateral or bilateral enlargement of the inferior olivary nucleus which shows a high signal intensity on T2-weighted images, with sometimes a cerebellar atrophy. Here we report 2 cases of healthy patients which present hemorrhagic brainstem cavernomas, complicated later by the development of palatal myoclonus and cerebellar ataxia, with MRI features corresponding to an (HOD) secondary to a (GMT) cavernoma. The purpose is to explain the mechanism of (HOD) subsequent to lesion in (GMT), and to describe magnetic resonance imaging features.

Lemmel syndrome: an unusual cause of biliary obstruction secondary to a duodenal juxta-ampullary diverticulum: a report of two cases.

Lemmel's syndrome is a rare cause of obstructive jaundice caused by a periampullary duodenal diverticulum compressing the intrapancreatic common bile duct with resultant bile duct dilatation, patients with Lemmel's syndrome usually present with abdominal pain or jaundice. Cross-sectional imaging is beneficial in making the diagnosis noninvasively, thus eliminating other pathologies of the peri-ampullary region. Although rare, we recognize the importance of considering this syndrome to be able to make a diagnosis and offer timely treatment. We present 2 cases of Lemmel's syndrome whose diagnosis is retained based on a CT scan and magnetic resonance cholangiopancreatography.