Uncommon cavernous malformation of the optic chiasm: a case report

Intracranial cavernous malformations (CMs) are not uncommon in the clinic and account for 10 to 20% of intracranial vascular diseases [1]. CMs are usually found in the brain parenchyma, and CMs of the optic chiasm are extremely rare, accounting for <1% of intracranial CMs [2]. The clinical symptoms of chiasmal CMs depend on the lesion size and amount of bleeding. If the CM is large or the volume of bleeding is high, then the chiasmal CM usually elicits stroke symptoms (that is, headache, vision loss and visual field defects) [3,4]. CMs involving the optic chiasm typically cause bilateral temporal visual field defects [5,6]. Here, we describe a case with a CM located on the right side of the optic chiasm, in which the patient presented with bilateral left homonymous hemianopsia in the visual field examination. After definitive diagnosis, the CM was removed surgically with a satisfactory outcome. We further review pertinent literature on the clinical and radiological features and surgical treatment of CMs.A 28-year-old male complained of blurred vision in his right eye, which started 2？months before presentation and had worsened about 10？days before. He was otherwise healthy and had no negative past medical history or history of ocular trauma or surgery. Two months before presentation, the patient visited the Department of Ophthalmology, First Hospital of Jilin University, due to a sudden onset of blurred vision. Eye examination showed no obvious abnormalities, and no exact diagnosis was made. The patient did not return to the clinic until the sudden worsening of blurred vision with forehead pain 10 days before presentation. His best-corrected visual acuity was 0.5 in the right eye and 0.4 in the left eye. Anterior segment slit-lamp examination showed no obvious abnormalities. Fundus examination revealed binocular mild primary optic atrophy. Visual field examination showed left homonymous hemianopsia. No other neurological abnormalities were found. No abnormalities we