Department of Ophthalmology, University of California San Francisco, San Francisco, CA, United States of America.
ForSight VISION6 Inc, Brisbane, CA, United States of America.
PLoS One. 2024 Nov 5;19(11):e0310564. doi: 10.1371/journal.pone.0310564. eCollection 2024.
Patients with intraocular silicone oil (SO) display higher odds of surgical failure after Ahmed glaucoma valve (AGV) implantation compared to patients without SO. However, the structural impact of SO exposure on silicone-made AGV tubes and the resulting changes in flow rate remain unexplored. This in-vitro study evaluated changes in tube dimensions and flow rates of AGV FP7 tubes after SO exposure to inform clinicians how such changes may impact AGV functionality.
AGV FP7 tube segments underwent accelerated aging to approximate 90 days of exposure to the following media: Balanced Salt Solution (BSS), 1000 centistokes (cs) SO, and 5000cs SO. Tube dimensions were measured before and after aging. A constant gravity flow test setup was created to measure flow rates through tubes before and after aging. The students' T-test was used to compare the mean change between groups post-aging.
Post-exposure, 1000cs and 5000cs SO tube segments increased in length by 5.94% and 5.55%, respectively, compared to 0.38% of BSS tubes (P < 0.05 for both). The inner lumen area expanded for tube segments in 1000cs and 5000cs SO by 11.75% and 2.70%, respectively, but contracted for tubes in BSS by -2.70% (P < 0.01 and P = 0.068 for 1000cs and 5000cs SO, respectively). Post aging, the flow rates increased on average by 61.0% and 98.6% for 1000cs and 5000cs SO, respectively, whereas flow rates for BSS tube segments slightly decreased by -4.92%. The difference was statistically significant for BSS vs. SO groups (P < 0.01 for both).
Prolonged exposure to SO structurally altered the AGV FP7 tube segments by expanding their cross-sectional area, potentially leading to increased flow rates. These results may inform clinicians about potential in-vivo interactions in patients with the simultaneous presence of glaucoma drainage devices and intraocular SO.
与无硅油患者相比，眼内硅油（SO）患者在接受 Ahmed 青光眼阀（AGV）植入术后手术失败的可能性更高。然而，SO 暴露对硅酮制造的 AGV 管的结构影响以及由此导致的流量变化仍未得到探索。本体外研究评估了 SO 暴露后 AGV FP7 管的管尺寸和流量变化，以告知临床医生这些变化如何影响 AGV 的功能。
AGV FP7 管段经过加速老化，以模拟以下介质暴露 90 天：平衡盐溶液（BSS）、1000 厘泊（cs）SO 和 5000cs SO。老化前后测量管尺寸。创建了一个恒重力流量测试装置，以测量老化前后管的流量。使用学生 t 检验比较老化后各组的平均变化。
暴露后，1000cs 和 5000cs SO 管段的长度分别增加了 5.94%和 5.55%，而 BSS 管段仅增加了 0.38%（两者均 P < 0.05）。管段在 1000cs 和 5000cs SO 中的内腔面积分别扩大了 11.75%和 2.70%，而在 BSS 中的管段则收缩了-2.70%（分别为 P < 0.01 和 P = 0.068）。老化后，1000cs 和 5000cs SO 的平均流量分别增加了 61.0%和 98.6%，而 BSS 管段的流量略有下降-4.92%。BSS 与 SO 组之间的差异具有统计学意义（两者均 P < 0.01）。
SO 的长期暴露通过扩大 AGV FP7 管段的横截面积来改变其结构，从而可能导致流量增加。这些结果可能会使临床医生了解同时存在青光眼引流装置和眼内 SO 的患者体内潜在的相互作用。
