Risk factors and visual results in cases of LASIK flap repositioning due to folds or dislocation: case series and literature review

Abstract

The presence of a corneal flap is a hallmark of laser in situ keratomileusis (LASIK), which offers advantages in terms of speed of visual recovery; however, it also carries the risk of postoperative flap displacement. We conducted a retrospective review of all consecutive eyes on which LASIK was performed by one single surgeon at an ophthalmological institute in Colombia between May 2005 and January 2011, looking for eyes that required flap repositioning. Demographic data, preoperative refraction, hinge position, and visual outcomes following flap repositioning were evaluated. A literature review on the subject was also conducted. We found 37 eyes on which flap repositioning was performed-12 eyes (32.4 %) with subluxation and 25 eyes (67.6 %) with folds; 21 eyes (56.8 %) had a temporal hinge and 16 eyes (43.2 %) had a superior hinge. With regard to the total number of eyes on which LASIK was performed (2,595), the overall incidence was 1.4 %. Sixteen out of 2,093 eyes (0.8 %) with a superior hinge and 21 out of 502 eyes (4.2 %) with a temporal hinge had flap-related postoperative complications (p < 0.00). A final best-corrected visual acuity (BCVA) between 20/20 and 20/25 was found in 75.7 % and a final BCVA between 20/30 and 20/40 was found in 21.6 %. Only one eye had less than 20/40 (previous amblyopia). From the eight eyes with a BCVA between 20/30 and 20/40, three had residual microstriae and one had corneal haze. Six eyes (16.2 %) lost two or more lines of BCVA. Flap subluxation or folds requiring flap repositioning were significantly more frequent when a temporal hinge was used.

<p>Survey of Postoperative Pain in Photorefractive Keratectomy Using Topical versus Oral Nonsteroidal Anti-Inflammatory Drugs</p>

“…PRK yields visual outcomes similar to laser-assisted in situ keratomileusis (LASIK) while eliminating flap-related complications associated with LASIK. 1,2 PRK is also less likely to structurally destabilize the cornea, with a lower ectasia risk as compared to LASIK. 3 This may allow for safer laser vision correction in a broader range of patients including some with thinner corneas or mild topographic abnormalities.…”

LASIK Flap

“…Early dislocation and folds not related to major trauma usually occur before the corneal wound has reepithelialized, typically within the first 24 hours after the operation. 13 They likely occur secondary to mechanical forces from eyelid movement, particularly in dry-eye states. 14 In a review of a surgeon's initial 1000 cases, 1.8% of eyes had malpositioned or striated flaps that required repositioning.…”

“…14 In a review of a surgeon's initial 1000 cases, 1.8% of eyes had malpositioned or striated flaps that required repositioning. 9 Other studies estimate the incidence of flap striae or displacement requiring repositioning at 0.1% to 2.5% 13,15,16 with flap striae about twice as common as flap dislocation.…”

“…Risk factors for flap slippage or dislocation include temporal or nasal hinge location (as opposed to superior hinge location) 13 and poor expression of interface fluid intraoperatively. 17 Preoperative brimonidine 0.2% has been associated with rates of flap striae or dislocation as high as 12.8% 18,19 ; in other studies, neither brimonidine 0.2%, dilute brimonidine, nor apraclonidine have been associated with flap adherence issues.…”

Experience in Gilan Comfort eye drops use of in patients after excimer laser surgery

“…Известно, что синд ром «сухого глаза» (ССГ) может быть вызван различными ятрогенными вмешательствами [5,6,8,9]. К такого рода вме-шательствам относится и лазерная коррекция зрения.…”