硝子体手術により腫瘍摘出を行った網膜血管増殖性腫瘍の1例

A case of retinal vasoproliferative tumor removed by pars plana vitrectomy

要約　目的：網膜血管増殖性腫瘍（RVPT）にはさまざまな治療法があるが，硝子体手術で直接腫瘍を摘出生検した症例は少ない。今回，硝子体手術を行い，腫瘍を摘出し，病態を安定させ，病理診断もできた症例を経験したので報告する。

症例：23歳，女性。左眼の視野狭窄を自覚し，近医受診を経て当院に紹介となった。

所見：初診時，左矯正視力は0.7で，前眼部に異常はなく，眼底は上鼻側に6×4乳頭径大の赤褐色腫瘤と黄斑部以外の広範囲に滲出性変化（網膜剝離，硬性白斑）を認め，網膜血管増殖性腫瘍と診断した。トリアムシノロンアセトニドのテノン囊下注射，ベバシズマブ硝子体内注射を行うも効果は乏しかった。その後，黄斑部まで網膜の滲出性変化が進行したため，受診9か月後に硝子体手術と超音波水晶体乳化吸引術（眼内レンズは毛様溝固定）を施行した。冷凍凝固術，網膜光凝固術を併施し腫瘍の大部分を摘出し，終術時にはシリコーンオイルを注入した。病理所見では，血管内皮に裏打ちされた脈管構造が増生し，一部に肉芽組織様の組織を示した。術後，徐々に滲出性変化は消失し，受診15か月後にシリコーンオイルを抜去した。受診22か月後に続発緑内障を認め，眼内レンズ強膜内固定術，マイクロフックトラベクロトミーを施行した。受診28か月後の現在，左矯正視力0.2，眼圧9mmHgで，病態は安定している。

結論：進行するRVPTの制御には硝子体手術による腫瘍摘出が有効であり，病理診断も可能とした。

Abstract　Purpose：Although there are various treatments for retinal vasoproliferative tumor（VPT）, the cases of resection and biopsies of tumor by vitrectomy are few. We report a case in which a retinal VPT was resected and diagnosed pathologically by vitrectomy.

Case：A 23-year-old female patient aware of the visual field defect of her left eye was examined at the ophthalmology clinic and was referred to our clinic.

Findings and clinical course：The left corrected visual acuity was 0.7. The anterior chamber and lens were clear. A reddish-brown mass that was 6×4 papillary size was located in the upper-nasal side of the fundus. Retinal detachment and hard exudates other than those in the macula were observed. A diagnosis of VPT was made. Sub-Tenon's triamcinolone acetonide injection and intravitreal bevacizumab were ineffective in treating the tumor. Because the exudative change had expanded to the macula, phacoemulsification with aspiration, injection of the intraocular lens（IOL）in sulcus, and vitrectomy were performed 9 months after the diagnosis. Most of the tumor was resected with cryopexy, photocoagulation, and injection of the silicone oil. Pathological findings showed hyperplasia of vessels lined on the vascular endothelium, and some granulation-like tissue. Exudative change gradually diminished after the surgery, and the silicone oil was removed in 15 months. Secondary glaucoma was observed, thus scleral fixation of IOL and interno trabeculotomy was performed in 22 months. Finally, the left corrected visual acuity was 0.2 and intraocular pressure was 9 mmHg. The condition of the patient is now stable.

Conclusions：Vitrectomy with resection of tumor is effective in controlling VPT and can be used for pathological diagnosis.