Punctal plugs may speed epithelial healing, visual recovery after LASEK

The study authors theorized that rapid wound healing would hinder dry eye, ocular surface inflammation and postoperative haze.

Issue: April 25, 2012

Preoperative punctal plug insertion facilitated corneal epithelial wound healing and improved visual recovery in eyes undergoing LASEK, a study found.

Plug insertion also prevented postoperative haze, the study authors said.

“The ocular surface damage in the plug group was milder than non-plug group concomitant with better [uncorrected distance visual acuity] at 1 week after surgery.” Takashi Kojima, MD, the corresponding author, said in an email interview.

Dr. Kojima and colleagues hypothesized that punctal occlusion would speed epithelial healing and thwart the inflammatory cascade resulting in postoperative haze.

“Generally, corneal epithelial damage induces ocular surface inflammation, which results in keratocyte activation,” Dr. Kojima said. “Keratocyte activation is thought to be a cause of haze formation after surface ablation surgery such as PRK, LASEK and epi-LASIK. We speculated that rapid wound healing in the plug group would suppress ocular surface inflammation, which would lead to decreased keratocyte activation and subsequent decreased haze formation.”

Results were published in the Journal of Refractive Surgery.

Patients and treatments

The retrospective case study included 363 eyes of 183 patients who underwent LASEK. After enrollment, 188 eyes of 95 patients underwent punctal plug insertion before LASEK; 175 eyes of 88 age- and gender-matched controls did not receive plugs preoperatively.

Mean patient age was 30.8 years in the punctal plug group and 30.3 years in the control group.

Schirmer testing was used to gauge tear function before surgery.

SuperFlex or SuperEagle plugs (EagleVision) were placed in the superior and inferior puncta. Loose or dislocated plugs were replaced. The superior punctal plug was removed in cases in which patients complained of epiphora at least 7 days after surgery.

Investigators used the EC-5000 excimer laser (Nidek) programmed with an optimized aspheric transition zone algorithm to perform ablation in all cases. The optical zone was adjusted according to corneal thickness and ablation depth, Dr. Kojima said.

A bandage soft contact lens (Acuvue, Johnson & Johnson Eye Care) was applied in all eyes that had LASEK. Bandage contact lenses were removed 4 days after surgery. Patients with poor epithelialization received bandage contact lenses for another 3 days.

Patients also received topical moxifloxacin and betamethasone sodium 0.01% eye drops five times daily for 7 days.

Wound healing, visual acuity and haze formation were evaluated 1 day, 2 days and 4 days after surgery.

Slit lamp photography with fluorescein staining was used to evaluate corneal wound healing, which was scored on a scale of 1 (complete re-epithelialization without superficial punctate keratopathy) to 4 (epithelial defect with mean diameter of less than 3 mm).

Results and conclusions

Study results showed a mean wound-healing grade of 2.13 in the plug group and 2.26 in the non-plug group 4 days postoperatively; the between-group difference was not significant.

“We found lower fluorescein scores in the plug group than the non-plug group 1 week after LASEK surgery,” Dr. Kojima said. “Moreover, our data showed significant correlation between fluorescein score and UDVA. From these findings, we speculated that lower irregularities of cornea accounted for better visual acuity.”

One week after surgery, mean fluorescein scores were 2.74 in the non-plug group and 1.73 in the plug group (P < .0001).

Also at 1 week, 82% of eyes in the plug group and 53% of eyes in the non-plug group achieved uncorrected distance visual acuity of 20/20 or better (P < .0001).

Mean logMAR corrected distance visual acuity was –0.15 in the plug group and –0.1 in the non-plug group (P < .0001). However, between-group differences in corrected distance visual acuity were not significant at 1 month and 3 months after surgery, Dr. Kojima and colleagues said.

Grade 1 haze formation was identified in three eyes (1.6%) in the plug group and 13 eyes (7.4%) in the non-plug group. The between-group difference was statistically significant (P = .014).

Shortcomings of the analysis included the non-randomized study design and examiners not being masked to treatment assignment.

Further study is needed to refine patient selection protocols and determine criteria for single plug insertion as opposed to dual insertion, Dr. Kojima and colleagues said. – by Matt Hasson

Reference:

Kojima T, Watabe T, Nakamura T, Ichikawa K, Satoh Y. Effects of preoperative punctal plug treatment on visual function and wound healing in laser epithelial keratomileusis. J Refract Surg. 2011;27(12):894-898.

For more information:

Takashi Kojima, MD, can be reached at Nagoya Eye Clinic, Meitetsu Kanayama, Building 3F, 25-1 Namiyose-cho, Atsuta-ku, Nagoya 456-0003, Japan; 81-52-872-0490; fax: 81-52-872-0491; email: tkojkoj@mac.com.
Disclosure: Dr. Kojima has no relevant financial disclosures.