黄斑部毛細血管拡張症2型（MacTel type 2）の5症例

The clinical course of five Japanese patients with macular telangiectasia type 2（MacTel2）

要約　目的：黄斑部毛細血管拡張症2型（MacTel type 2）は，欧米と比較して日本人の症例報告が少ない。今回，当院で5症例を経験したので報告する。

症例：女性4例，男性1例。全例両眼性で，平均年齢は61.2歳，平均観察期間は1年11か月であった。

所見：［症例1］ 75歳，女性。初診時，光干渉断層計（OCT）で左眼中心窩網膜内層の囊胞様所見（ILC）と外層欠損が，両眼に傍中心窩の網膜神経節複合体（GCC）の菲薄化がみられ，専門医へ紹介し精査により本疾患と診断された。［症例2］ 46歳，女性。初診から両眼ILCとGCCの菲薄化がみられた。3年後，左眼に網膜下新生血管が出現し，蛍光眼底造影から本疾患と診断した。［症例3］ 68歳，男性。右眼に中心窩網膜内色素沈着とGCCの菲薄化，左眼に黄斑円孔がみられ，黄斑円孔術後の眼底自発蛍光（FAF），OCT angiography（OCTA）から本疾患と診断した。［症例4］ 75歳，女性。初診から10か月後に両眼にILCが出現し，OCTAと合わせて本疾患と臨床診断した。［症例5］ 42歳，女性。両眼macular microholeを疑い3年3か月経過観察したが，両眼の緩徐進行性の経過と当時のOCT，FAF，GCC所見を再検討し，本疾患であったと診断した。

結論：診断に苦慮する両眼黄斑変性のなかに，MacTel type 2が少なからず含まれている可能性がある。

Abstract　Purpose：To report the clinical course of five Japanese patients in the same clinic with macular telangiectasia type 2（MacTel2）.

Cases：This retrospective observational case series includes ten eyes of five patients（four women and a man）with MacTel2. The mean age and follow-up duration were 61.2 years and 23.4 months.

Findings：［Patient 1/a 75-year-old woman］At the first visit to our clinic, optical coherence tomography（OCT）demonstrated an inner lamellar cyst（ILC）and macular ellipsoid zone（EZ）loss in the left eye and macular ganglion cell complex（GCC）thickness showed thinning in both eyes. She was referred to another hospital and was diagnosed with MacTel2.［Patient 2/a 46-year-old woman］After three years of follow-up for bilateral macular degeneration, OCT revealed ILC and EZ loss in both eyes with subretinal neovascularization in the left eye. She was diagnosed with MacTel2 together with fluorescein angiography（FA）findings.［Patient 3/a 68-year-old man］At the first visit to our clinic, OCT demonstrated intraretinal macular pigmentation of the right eye and a macular hole with ILC in the left eye. He was diagnosed with MacTel2 by vitrectomy for the macular hole.［Patient 4/a 75-year-old woman］At the first visit to our clinic, macular EZ in both eyes was slightly irregular on OCT. Ten months later, OCT revealed ILC and EZ loss and she was clinically diagnosed with MacTel2.［Patient 5/a 42-year-old woman］She had been followed up for 39 months since 2010 as she had a binocular macular microhole. We confirmed that she had MacTel2 by reexamining the FA and OCT findings at that time.

Conclusion：Based on these findings, we believe that MacTel2 should be suspected in some of the difficult-to-diagnose bilateral macular degeneration cases.