白内障術後に発症した浸潤型副鼻腔真菌症による鼻性視神経症の1例

A case of rhinogenic optic neuritis caused by invasive fungal rhinosinusitis after cataract surgery

要約　目的：白内障術後の経過観察中であったため，浸潤型副鼻腔真菌症による鼻性視神経症と比較的早期に診断・加療され，視力予後良好であった1例を経験したため報告する。

症例：当科で右水晶体再建術を施行された89歳の男性。

所見：白内障術後7日より右視力低下を自覚し，術後9日の診察で右最高矯正視力（0.07）と術直後と比べ低下していた。細隙灯検査では明らかな異常所見はなく，動的視野検査で右中心〜上耳側視野障害，限界フリッカ値（CFF）の低下を認めた。画像検査では左副鼻腔炎，右の篩骨洞骨破壊所見を認めたため，耳鼻咽喉科にて副鼻腔手術を施行された。術中右視神経管の中枢側に骨融解様所見を認め，病理検査で左副鼻腔真菌塊様肉芽組織からAspergillus fumigatusが検出された。以上から左副鼻腔真菌症に伴う右浸潤型副鼻腔真菌症による鼻性視神経症と診断され，副鼻腔手術当日からアムホテリシンBで加療された。術後6か月までの経過観察で右視力は（1.2），視野，CFFも改善し，経過良好であった。

結論：浸潤型副鼻腔真菌症による鼻性視神経症により1〜2週間程度で急激な視機能障害をきたしたが，早期治療により良好な視機能改善を得ることができた症例を経験した。

Abstract　Objective：To report a case of nasal optic neuropathy caused by invasive sinus fungal infection that was diagnosed and treated during follow-up after cataract surgery, with a good visual prognosis.

Case：An 89-year-old man who underwent right lens reconstruction at our department.

Findings：The patient began experiencing right visual acuity loss 7 days after cataract surgery, and on examination 9 days after surgery, his right best corrected visual acuity was 0.07, which was a decrease from his post-operative acuity. Slit-lamp examination revealed no obvious abnormalities, and dynamic visual field testing revealed central to upper temporal visual field defects in the right eye and a decrease in mean central flicker value. Imaging studies revealed left sinusitis and bony destruction of the right ethmoid sinus. Intraoperatively, osteolysis-like findings were observed on the central side of the right optic nerve canal, and Aspergillus fumigatus was detected in the left sinus fungal mass-like granulation tissue on pathological examination. Based on the above, a diagnosis of rhinophyma due to right invasive sinus fungal infection associated with left sinus fungal infection was made, and the patient was treated with amphotericin B from the day of sinus surgery. After a 6-month follow-up, the patient's visual acuity was（1.2）, and visual field and CFF had improved.

Conclusions：We have outlined a case of nasal optic neuropathy caused by invasive sinonasal fungal infection, which resulted in rapid visual dysfunction within 1-2 weeks, but early treatment resulted in good improvement of visual function.