A Case of Double Depressor Palsy due to Bilateral Thalamic Infarction

ABSTRACT

PURPOSE: We report a rare case of double depressor palsy after bilateral thalamus infarction. CASE SUMMARY: A 47-year-old male presented with complaints of diplopia upon awakening. He had atrial fibrillation, mitral valve regurgitation, aortic valve regurgitation and a history of spleen infarction 1 year prior. His right eye was hypertrophic and right eye downgaze was limited unilaterally of equal degree in adduction and abduction. Right eye horizontal and upward movements were intact. Left eye movement was intact in all directions. Pupillary light reflex response and convergence test were normal. Nystagmus was not observed. The patient was diagnosed with double depressor palsy of the right eye. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the brain showed an old infarction of the left thalamus and diffusion MRI showed acute infarction of the right thalamus. The patient's daily warfarin dose was 2 mg and was increased to 5 mg with cilostazol 75 mg two times a day. Seven weeks later, the patient's ocular movement revealed near normal muscle action and, subjectively, the patient was diplopia-free. CONCLUSIONS: Double depressor palsy is a extremely rare disease and can be caused by bilateral thalamic infarction.