Background: Opposite clear corneal incisions (OCCIs) have been reported to red uce pre-existing astigmatism (PEA) during cataract surgery. Our goal was to eva luate the effect of OCCIs on correcting PEA in cataract su...Background: Opposite clear corneal incisions (OCCIs) have been reported to red uce pre-existing astigmatism (PEA) during cataract surgery. Our goal was to eva luate the effect of OCCIs on correcting PEA in cataract surgery. Methods: Nonran domized prospective study. Thirty-four patients with PEA of greater than 1.5 di opters (D) underwent clear cornea phacoemulsification cataract extraction with 3 .2-mm OCCIs (OCCI group). The control group consisted of 23 successive patients with PEA < 1.5 D who underwent cataract extraction without OCCI. Best-correcte d visual acuity, keratometry and refraction were recorded for all patients pre- operatively and post-operatively. Results: Using keratometric findings, mean as tigmatism correction was 1.3 D (±0.9 SD; decreased from 2.6 D preoperatively to 1.4 D post-operatively) in the OCCI group but only 0.4 D in the control group (P < 0.005), 8 months postoperatively. Vector analysis of astigmatism correction showed greater change for OCCI patients (1.8 D vs 1.0 D, P=0.002). Using the Ho lladay method for calculating surgically induced refractive change (SIRC), the O CCI group showed a higher value of SIRC (-1.6 D vs-0.97 D), but this was not s tatistically significant. The OCCI patients showed a greater and significant cha nge in refraction spherical equivalent than the controls. No complications relat ed to OCCI or cataract surgery occurred during the follow-up period. Conclusion s: Opposite clear cornea incision seems to be a simple, predictable, safe and ef fective procedure in reducing pre-existing corneal astigmatism in cataract surg ery. It has an enhanced effect in correcting astigmatism compared to a single cl ear cornea incision when using keratometric findings value but not when using re fractive data. Future studies are needed to document the long-term effect of OC CI and to evaluate the correlation between incisions of different size and astig matism correction.展开更多
文摘Background: Opposite clear corneal incisions (OCCIs) have been reported to red uce pre-existing astigmatism (PEA) during cataract surgery. Our goal was to eva luate the effect of OCCIs on correcting PEA in cataract surgery. Methods: Nonran domized prospective study. Thirty-four patients with PEA of greater than 1.5 di opters (D) underwent clear cornea phacoemulsification cataract extraction with 3 .2-mm OCCIs (OCCI group). The control group consisted of 23 successive patients with PEA < 1.5 D who underwent cataract extraction without OCCI. Best-correcte d visual acuity, keratometry and refraction were recorded for all patients pre- operatively and post-operatively. Results: Using keratometric findings, mean as tigmatism correction was 1.3 D (±0.9 SD; decreased from 2.6 D preoperatively to 1.4 D post-operatively) in the OCCI group but only 0.4 D in the control group (P < 0.005), 8 months postoperatively. Vector analysis of astigmatism correction showed greater change for OCCI patients (1.8 D vs 1.0 D, P=0.002). Using the Ho lladay method for calculating surgically induced refractive change (SIRC), the O CCI group showed a higher value of SIRC (-1.6 D vs-0.97 D), but this was not s tatistically significant. The OCCI patients showed a greater and significant cha nge in refraction spherical equivalent than the controls. No complications relat ed to OCCI or cataract surgery occurred during the follow-up period. Conclusion s: Opposite clear cornea incision seems to be a simple, predictable, safe and ef fective procedure in reducing pre-existing corneal astigmatism in cataract surg ery. It has an enhanced effect in correcting astigmatism compared to a single cl ear cornea incision when using keratometric findings value but not when using re fractive data. Future studies are needed to document the long-term effect of OC CI and to evaluate the correlation between incisions of different size and astig matism correction.
