Findings, Diagnosis & Discussion

Findings: Abnormal moderate hyperintensity in the periaqueductal regions, medial thalami, and third ventricular walls.

Diagnosis: Wernicke encephalopathy

Discussion: Wernicke encephalopathy is a neurologic disorder that results from vitamin B1 (thiamine) deficiency. Most patients have a history of alcohol abuse. Other possible causes include hyperemesis gravidarum, prolonged infectious conditions, carcinoma, anorexia nervosa, and prolonged starvation. The syndrome is associated with the classic clinical triad of ataxia, oculomotor cranial neuropathy, and altered levels of consciousness.

Typical pathologic findings in Wernicke encephalopathy include necrosis, vascular proliferation, and glial proliferation in the medial thalami, mammillary bodies, periaqueduct, floor of the fourth ventricle, and superior vermis. The radiologic manifestations are high signal intensity areas on T2 weighted images in these anatomic locations. These areas may or may not enhance. In some cases, enhancement or abnormal signal in the mammillary bodies may be the sole manifestation of Wernicke encephalopathy.

MRI is sensitive for the detection of lesions of Wernicke encephalopathy. The lesions are potentially reversible with thiamine supplementation if detected early.

References

1. Grossman, RI, Yousem, DM. Neuroradiology: The Requisites, Second Edition. Mosby; St. Louis. 2003.

2. Gallucci M, Bozzao A, Spendiani A, Masciocchi C, Passsariello R. Wernicke encephalopathy: MR findings in five patients. AJNR 1990;11:887-892.

3. Zhong, C et al. MR imaging of nonalcoholic Wernicke encephalopathy: a follow-up study. AJNR 2005; 26:2301-2305.