白血病により視神経乳頭腫脹をきたした2例

Optic disc swelling in two cases of leukemia

要約　白血病に視神経乳頭腫脹が併発した2例を経験した。1例は44歳男性で，3年前に急性骨髄性白血病が発症し，二度の化学療法で寛解していた。3週間前に両眼の視力障害を自覚した。受診時の視力は，右手動弁，左眼0.04であった。乳頭腫脹が両眼にあった。化学療法と放射線照射で乳頭腫脹が寛解し，視力は右0.4，左0.6に回復した。他の1例は16歳男性で，1か月前に風邪様の症状があり，右眼の眼瞼腫脹と複視が続発した。当科受診直前に急性リンパ性白血病と診断された。近見視力は右0.3，左0.6で，右眼に乳頭腫脹があり，両眼に網膜出血があった。磁気共鳴画像検査（MRI）で右の副鼻腔と眼窩に腫瘤があり，視神経が鼻側に圧排されていた。抗白血病薬の全身投与と髄腔内注入で，眼窩腫瘍と乳頭腫脹は寛解した。視神経乳頭腫脹の原因は，第1例では浸潤性視神経症，第2例では圧迫性視神経症と推定した。

Abstract.　A 44-year-old man had been diagnosed with acute myeloblastic leukemia 3 years before which was controlled by chemotherapy. He noticed blurring in both eyes 3 weeks before. His visual acuity was hand motion right and 0.04 left. Both eyes showed optic disc swelling. Chemotherapy and radiation induced regression of disc swelling with the visual acuity of 0.4 right and 0.6 left. Another 16-year-old boy had developed signs of common cold one month before followed by diplopia and swelling of right eyelids. He was diagnosed with acute lymphocytic leukemia. His corrected visual acuity was 0.3 right and 0.6 left. The right eye showed optic disc swelling. Both eyes showed retinal hemorrhages. Magnetic resonance imaging（MRI）showed a tumor in the right paranasal sinus and orbit. The right optic nerve was displaced nasally by the tumor. Systemic and intrathecal chemotherapy induced regression of orbital tumor and disc swelling. It appeared that the optic disc swelling was caused by leukemic infiltration in the optic nerve in the first case and by compression optic neuropathy in the second.