白內障手術前後角膜生物力學之比較

The Changes of Corneal Biomechanical Properties after Cataract Surgery

徐文錦(Wen-Jin Hsu) ； 曾佳慧(Chia-Hui Tseng) ； 何一滔(Yi-Tau Ho) ； 林思源(Szu-Yuan Lin) ； 林素玲(Shuan-Liang Lin)

《中華民國眼科醫學會雜誌》 48卷4期 (2009/12) Pp. 517-527

https://doi.org/10.30048/ACTASOS.200912.0030

摘要

Purpose: This study evaluates the changes of corneal biomechanical properties after cataract surgery with IOL implantation.
Methods: Twenty-four volunteers were enrolled in this study and they were divided into two groups. Phacoemusification with foldable IOL implantation was arranged for the eighteen volunteers in group 1. Extra-capsule lens extraction (ECCE) combined with PMMA IOL was performed on the 6 subjects in group 2. Corneal hystereis and corneal resistance factors were measured preoperatively and 1 week, 1 month and 3 months postoperatively after the surgery by ORA. Central corneal thickness was measured using the ORA's integrated handheld ultrasonic pachymeter at these times.
Result: In group 1, mean CH decreased from the preoperative 10.52±1.25mmHg to 9.45±0.15 mmHg (p＜0.005) one week after surgery and then gradually returned to the basal level. Mean CRF also decreased from 9.97±0.58 mmHg to 8.50±0.17 mmHg (p＜0.005) one week after the surgery and then gradually returned to the basal level. There was no significant difference of CCT before or even three months after the surgery. In group 2, there was an obvious increase (p＜0.005) in CCT one week and one month after the surgery. CH sharply decreased from 11.54±0.85mmHg to 9.45±0.15 mmHg (one week after the surgery), and then returned back to 9.80±0.52 mmHg (one month after the surgery). CRF sharply decreased from 10.58±0.58 mmHg to 8.78±1.47 mmHg (one week after the operation), and then also slightly returned back to 9.58±0.42 mmHg (one month after the surgery). The CCT increased just one week after the surgery and lasted for one month due to corneal edema. Fortunately, all three corneal biomechanics returned to pre-operative basal levels after 3 months in group 2.
Conclusion: CH and CRF are relatively low and last temporarily with a variable span after cataract surgery. This phenomenon likely results from the procedures during the surgery that affect the corneal endothelial cells as to change viscoelastic properties and lower the damping capacity of the cornea. In addition, phacoemu-sification with small incisions may have better impact on corneal biomechanical properties for a short time as compared to extra-capsular lens extraction which wounds damaged tissues surrounding the cornea and sclera on a large scale.

並列摘要

Purpose: This study evaluates the changes of corneal biomechanical properties after cataract surgery with IOL implantation.
Methods: Twenty-four volunteers were enrolled in this study and they were divided into two groups. Phacoemusification with foldable IOL implantation was arranged for the eighteen volunteers in group 1. Extra-capsule lens extraction (ECCE) combined with PMMA IOL was performed on the 6 subjects in group 2. Corneal hystereis and corneal resistance factors were measured preoperatively and 1 week, 1 month and 3 months postoperatively after the surgery by ORA. Central corneal thickness was measured using the ORA's integrated handheld ultrasonic pachymeter at these times.
Result: In group 1, mean CH decreased from the preoperative 10.52±1.25mmHg to 9.45±0.15 mmHg (p＜0.005) one week after surgery and then gradually returned to the basal level. Mean CRF also decreased from 9.97±0.58 mmHg to 8.50±0.17 mmHg (p＜0.005) one week after the surgery and then gradually returned to the basal level. There was no significant difference of CCT before or even three months after the surgery. In group 2, there was an obvious increase (p＜0.005) in CCT one week and one month after the surgery. CH sharply decreased from 11.54±0.85mmHg to 9.45±0.15 mmHg (one week after the surgery), and then returned back to 9.80±0.52 mmHg (one month after the surgery). CRF sharply decreased from 10.58±0.58 mmHg to 8.78±1.47 mmHg (one week after the operation), and then also slightly returned back to 9.58±0.42 mmHg (one month after the surgery). The CCT increased just one week after the surgery and lasted for one month due to corneal edema. Fortunately, all three corneal biomechanics returned to pre-operative basal levels after 3 months in group 2.
Conclusion: CH and CRF are relatively low and last temporarily with a variable span after cataract surgery. This phenomenon likely results from the procedures during the surgery that affect the corneal endothelial cells as to change viscoelastic properties and lower the damping capacity of the cornea. In addition, phacoemu-sification with small incisions may have better impact on corneal biomechanical properties for a short time as compared to extra-capsular lens extraction which wounds damaged tissues surrounding the cornea and sclera on a large scale.

並列關鍵字

Ocular response analyzer ORA ； Corneal hysteresis CH ； Corneal resistance factor CRF