Department of Ophthalmology, Teine Keijinkai Hospital, Sapporo, Japan.
Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N-15, W-7, Kita-Ku, Sapporo, 060-8638, Japan.
Graefes Arch Clin Exp Ophthalmol. 2023 Jul;261(7):1901-1912. doi: 10.1007/s00417-023-06004-5. Epub 2023 Feb 16.
The aim of this study was to analyze the anatomical choroidal vascular layers and the changes in idiopathic macular hole (IMH) eyes over time after vitrectomy.
This is a retrospective observational case-control study. Fifteen eyes from 15 patients who received vitrectomy for IMH and age-matched 15 eyes from 15 healthy controls were enrolled in this study. Retinal and choroidal structures were quantitatively analyzed before vitrectomy and 1 and 2 months after surgery using spectral domain-optical coherence tomography. Each choroidal vascular layer was divided into the choriocapillaris, Sattler's layer, and Haller's layer, and then, the choroidal area (CA), luminal area (LA), stromal area (SA), and central choroidal thickness (CCT) were calculated using binarization techniques. The ratio of LA to CA was defined as the L/C ratio.
The CA, LA, and L/C ratios were 36.9 ± 6.2, 23.4 ± 5.0, and 63.1 ± 7.2 in the choriocapillaris of IMH and were 47.3 ± 6.6, 38.3 ± 5.6, and 80.9 ± 4.1 in that of control eyes, respectively. Those values were significantly lower in IMH eyes than in control eyes (each P < 0.01), whereas there was no significant difference in total choroid, Sattler's layer, and Haller's layer or CCT. The ellipsoid zone defect length showed a significant negative correlation with the L/C ratio in total choroid and with CA and LA in the choriocapillaris of IMH (R = - 0.61, P < 0.05, R = - 0.77, P < 0.01, and R = - 0.71, P < 0.01, respectively). In the choriocapillaris, the LA were 23.4 ± 5.0, 27.7 ± 3.8, and 30.9 ± 4.4, and the L/C ratios were 63.1 ± 7.2, 74.3 ± 6.4, and 76.6 ± 5.4 at baseline, 1 month, and 2 months after vitrectomy, respectively. Those values showed a significant increase over time after surgery (each P < 0.05), whereas the other choroidal layers did not alter consistently with respect to changes in choroidal structure.
The current OCT-based study demonstrated that the choriocapillaris was exclusively disrupted between choroidal vascular structures in IMH, which may correlate with the ellipsoid zone defect. Furthermore, the L/C ratio of choriocapillaris recovered after IMH repair, suggesting an improved balance between supply and demand of oxygen that has collapsed due to temporary loss of central retinal function by IMH.
本研究旨在分析特发性黄斑裂孔（IMH）患者玻璃体切除术后脉络膜解剖血管层的变化。
这是一项回顾性观察性病例对照研究。本研究纳入了 15 例接受玻璃体切除治疗 IMH 的患者的 15 只眼，以及年龄匹配的 15 例健康对照者的 15 只眼。使用频域光学相干断层扫描术（OCT）分别于玻璃体切除术前和术后 1 个月及 2 个月对视网膜和脉络膜结构进行定量分析。将每个脉络膜血管层分为脉络膜毛细血管层、Sattler 层和 Haller 层，然后使用二值化技术计算脉络膜面积（CA）、管腔面积（LA）、基质面积（SA）和中央脉络膜厚度（CCT）。LA 与 CA 的比值定义为 L/C 比值。
IMH 患者脉络膜毛细血管层的 CA、LA 和 L/C 比值分别为 36.9±6.2、23.4±5.0 和 63.1±7.2，对照组分别为 47.3±6.6、38.3±5.6 和 80.9±4.1。IMH 眼的这些值明显低于对照组（均 P<0.01），而总脉络膜、Sattler 层和 Haller 层或 CCT 无显著差异。椭圆体带缺损长度与总脉络膜的 L/C 比值以及脉络膜毛细血管层的 CA 和 LA 呈显著负相关（R=−0.61，P<0.05；R=−0.77，P<0.01；R=−0.71，P<0.01）。脉络膜毛细血管层的 LA 分别为 23.4±5.0、27.7±3.8 和 30.9±4.4，L/C 比值分别为 63.1±7.2、74.3±6.4 和 76.6±5.4，于玻璃体切除术后 1 个月和 2 个月分别为基线时、1 个月和 2 个月。这些值在手术后随时间推移呈显著增加（均 P<0.05），而其他脉络膜层的结构变化并不一致。
本基于 OCT 的研究表明，在 IMH 中脉络膜血管结构之间，脉络膜毛细血管层是唯一受到破坏的，这可能与椭圆体带缺损有关。此外，IMH 修复后脉络膜毛细血管层的 L/C 比值恢复，表明由于 IMH 暂时丧失中心视网膜功能导致的氧供需平衡得到改善。
