PURPOSE This study aimed to analyze the choroidal characteristics in eyes with polypoidal choroidal vasculopathy (PCV, affected eyes) and unaffected fellow eyes, and investigated the longitudinal changes in the choroidal structure of fellow eyes in patients with unilateral PCV. METHODS We retrospectively reviewed the medical records of 55 treatment-naïve patients with unilateral PCV. The choroidal thickness and vascularity between PCV affected eyes, unaffected fellow eyes, and normal control eyes were compared. Structural changes in the choroid of the fellow eyes were reviewed during follow-up. RESULTS PCV eyes had thicker subfoveal choroidal thickness (SFCT) (p < 0.001), greater ratio of Haller layer to SFCT (p < 0.001), and lower choroidal vascularity index (p = 0.023), compared to controls. In unaffected fellow eyes, the ratio of the Haller layer to SFCT was greater (p < 0.001) than in controls. During a 58.91-month mean follow-up, nine (16%) fellow eyes developed new PCV. These eyes showed a greater ratio of Haller layer to SFCT at baseline (p < 0.001) compared to the other fellow eyes. We also observed a numerical change in the choroidal vascularity index during follow-up of fellow eyes that developed new PCV. CONCLUSION The dilation of the Haller layer was prominent in PCV eyes and fellow eyes, compared to normal controls. In the fellow eyes that developed new PCV lesions, there were changes in the choroidal vascularity during follow-up.

中文翻译：

---

单侧息肉状脉络膜血管病患者脉络膜厚度和血管分布分析。

目的 本研究旨在分析息肉状脉络膜血管病变（PCV，受影响的眼睛）和未受影响的对侧眼的脉络膜特征，并调查单侧 PCV 患者对侧眼脉络膜结构的纵向变化。方法 我们回顾性地审查了 55 名未经治疗的单侧 PCV 患者的医疗记录。比较了 PCV 受影响的眼睛、未受影响的对侧眼睛和正常对照眼睛之间的脉络膜厚度和血管分布。在随访期间回顾了对侧眼脉络膜的结构变化。结果与对照组相比，PCV 眼中心凹下脉络膜厚度 (SFCT) 更厚 (p < 0.001)，Haller 层与 SFCT 的比率更大 (p < 0.001)，脉络膜血管指数更低 (p = 0.023)。在不受影响的同胞眼中，Haller 层与 SFCT 的比率大于对照（p < 0.001）。在 58.91 个月的平均随访期间，九 (16%) 只对侧眼出现了新的 PCV。与其他对侧眼睛相比，这些眼睛在基线时显示出更大的哈勒层与 SFCT 的比率（p < 0.001）。我们还观察到在对发展出新 PCV 的对侧眼进行随访期间脉络膜血管指数的数值变化。结论 与正常对照相比，PCV 眼和对侧眼的 Haller 层扩张明显。在出现新 PCV 病变的对侧眼中，随访期间脉络膜血管分布发生了变化。与其他对侧眼睛相比，这些眼睛在基线时显示出更大的哈勒层与 SFCT 的比率（p < 0.001）。我们还观察到在对发展出新 PCV 的对侧眼进行随访期间脉络膜血管指数的数值变化。结论 与正常对照相比，PCV 眼和对侧眼的 Haller 层扩张明显。在出现新 PCV 病变的对侧眼中，随访期间脉络膜血管分布发生了变化。与其他对侧眼睛相比，这些眼睛在基线时显示出更大的哈勒层与 SFCT 的比率（p < 0.001）。我们还观察到在对发展出新 PCV 的对侧眼进行随访期间脉络膜血管指数的数值变化。结论 与正常对照相比，PCV 眼和对侧眼的 Haller 层扩张明显。在出现新 PCV 病变的对侧眼中，随访期间脉络膜血管分布发生了变化。