Swept-source OCT（DRI OCT Triton®）とspectral-domain OCT（3D OCT1000®）の比較

Comparison of swept-source and spectral-domain optical coherence tomography

要約　目的：Swept-source光干渉断層計（SS-OCT）とspectral-domain光干渉断層計（SD-OCT）による同一眼での検査結果の比較。

対象と方法：両機種による検査を行った眼科患者255人467眼を対象とした。年齢は14〜92歳，平均66±12歳で，網膜硝子体疾患317眼，前眼部疾患129眼，炎症性疾患19眼などである。Vogt-小柳-原田病の1例2眼では，脈絡膜厚を測定した。

結果：SS-OCTはSD-OCTよりも有意に画質が鮮明で，測定可能率が高く，低画質画像の頻度が低かった（p＜0.01）。固視不良眼での測定可能率と黄斑前膜の検出率には有意差がなかった。SS-OCTはSD-OCTよりも部分後部硝子体剝離の検出率が高かった（p＜0.01）。Vogt-小柳-原田病での網脈絡膜厚はSD-OCTでは測定できず，SS-OCTでは測定でき，加療による脈絡膜厚の減少を計測できた。

結論：網膜硝子体疾患などに対しSS-OCTはSD-OCTよりも，より詳細に測定できた。

Abstract　Purpose: To report and compare the findings by swept-source optical coherence tomography（SS-OCT）and spectral-domain OCT（SD-OCT）.

Cases and Method: This study was made on 467 eyes of 255 patients. The age ranged from 14 to 92 years, average 66±12 years. The series included 317 eyes with vitreous or fundus disorders, 129 eyes with anterior segment disorders, and 19 eyes with inflammatory lesions. All the eyes were examined by SS-OCT and SD-OCT. Thickness of the choroid was measured in both eyes of a case of Vogt-Koyanagi-Harada（VKH）disease.

Results: SS-OCT showed significantly clearer image, higher rate of acquisition, and lower rate of low-quality image than SD-OCT（p＜0.01）. There was no difference in detecting epiretinal membrane or rate of acquisition in eyes with poor fixation between the two methods. SS-OCT showed higher rate of detection of partial posterior vitreous detachment than SD-OCT（p＜0.01）. Thickness of the choroid and its changes during treatment could only be recorded by SS-OCT.

Conclusion: SS-OCT provided more detailed information regarding the vitreous, retina and the choroid than SD-OCT.