Unusual Clinical Presentations and Mechanism of Bilateral Thalamic Infarcts: A Case Series (P06.250)

Abstract

Objective: To highlight the breadth of clinical syndromes and mechanisms of artery of Percheron territory strokes. Background Simultaneous bilateral thalamic infarction represents a relatively rare stroke syndrome. The underlying vascular anatomy often suspected in these cases is a variant of the posterior circulation first described by Percheron in 1975, wherein the paramedian thalami as well as rostral midbrain structures are supplied by a single arterial branch of the proximal posterior cerebral artery. The artery of Percheron, though difficult to visualize even with conventional angiography, may be present in as many as one third of patients. Pathophysiologically, these strokes can be attributed to athero- or thromboembolic phenomena, or result from hypoperfusion due to poor cardiac output. The classical clinical presentation is described as a triad of hypersomnolence, amnesia, and vertical gaze paresis. However, in practice, presentations can be far more variable, with a myriad of cognitive and behavioral changes in addition to eye findings, representing a challenge to the clinician in terms of both lesion localization and determination of etiology. Design/Methods: Case series. Data collected from chart review, serial neurologic examinations. Results: We present a series of three cases of bilateral paramedian thalamic infarcts. In one, we report for the first time an association with WEBINO (wall-eyed bilateral internuclear ophthalmoplegia) syndrome, itself a rare phenomenon with fewer than 20 cases reported in the English literature.We describe another patient with unilateral oculomotor nerve palsy, an unusual stroke presentation. Finally, we present a patient with amnesia and behavioral changes whose stroke occurred in the setting of atrial myxoma. Conclusions: Patients with artery of Percheron territory strokes may present with unusual clinical findings that can confound the diagnosis and potentially delay treatment. The protean clinical presentation represents a challenge to the clinician with respect to lesion localization and etiology. Disclosure: Dr. Manchak has nothing to disclose. Dr. Odrzywolski has nothing to disclose. Dr. Kelly has nothing to disclose. Dr. Benesch has nothing to disclose.