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Reduced application time for prophylactic mitomycin C in photorefractive keratectomy
Vanee V Virasch1, Parag A Majmudar, Randy J Epstein
1Rush University Medical Center, Chicago, Illinois, USA.
Objective:
To determine whether the duration of mitomycin C (MMC) 0.02% application affects visual outcome or the incidence of subepithelial haze in patients undergoing photorefractive keratectomy (PRK) with prophylactic administration of MMC.
Design:
Retrospective, comparative case series.
Participants:
Two hundred sixty-nine eyes undergoing PRK.
Methods:
This was a retrospective comparative case series that included 269 eyes that underwent PRK with prophylactic MMC application for 120 seconds (group 1, n = 74), 60 seconds (group 2, n = 36), or 12 seconds (group 3, n = 159). The mean preoperative spherical equivalent was -6.49 diopters (D) in group 1, -6.77 D in group 2, and -7.10 D in group 3. Photorefractive keratectomy was performed using a modified nomogram. All eyes received a single intraoperative application of MMC (0.02%) after laser ablation for the above specified durations.
Main Outcome Measures:
Best-corrected visual acuity and corneal haze score.
Results:
Best-corrected visual acuity was 20/23 in group 1, 20/20 in group 2, and 20/21 in group 3. The mean haze score+/-standard deviation (scale, 0.00-4.00) was 0.11+/-0.31 in group 1, 0.14+/-0.28 in group 2, and 0.07+/-0.20 in group 3 throughout a mean follow-up of 31 months in group 1, 16 months in group 2, and 10 months in group 3. No eyes had a haze score of more than 1.00.
Conclusions:
There was no statistically significant difference in postoperative best-corrected visual acuity or haze scores among the 3 groups. Administration of prophylactic MMC 0.02% for 12 seconds after PRK seems to be equally efficacious for haze prophylaxis when compared with longer application times of 60 and 120 seconds.
Insights
Shorter application times of mitomycin C (MMC) during photorefractive keratectomy (PRK) are as effective as longer durations for preventing subepithelial haze. This study found no significant difference in visual outcomes or haze incidence with 12-second versus 60- or 120-second MMC application.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Ophthalmic Pharmacology
Background:
- Photorefractive keratectomy (PRK) is a common refractive surgery.
- Mitomycin C (MMC) is used to prevent corneal haze after PRK.
- The optimal duration for MMC application is not well-established.
Purpose of the Study:
- To investigate the effect of varying durations of prophylactic mitomycin C (MMC) 0.02% application on visual outcomes and subepithelial haze after photorefractive keratectomy (PRK).
Main Methods:
- A retrospective comparative case series involving 269 eyes undergoing PRK.
- Eyes were divided into three groups based on MMC application duration: 120 seconds (n=74), 60 seconds (n=36), and 12 seconds (n=159).
- Outcomes assessed included best-corrected visual acuity (BCVA) and corneal haze scores over a mean follow-up of 10-31 months.
Main Results:
- No statistically significant differences in BCVA were observed among the groups (20/23, 20/20, 20/21 respectively).
- Mean corneal haze scores were low across all groups (0.11, 0.14, 0.07 respectively) with no scores exceeding 1.00.
- Follow-up durations varied: 31 months for 120s, 16 months for 60s, and 10 months for 12s.
Conclusions:
- The duration of prophylactic MMC 0.02% application after PRK does not significantly impact postoperative visual acuity or the incidence of subepithelial haze.
- A 12-second application of MMC appears to be as effective as longer durations (60 and 120 seconds) for haze prophylaxis.
