Consider These Best Practices When Performing PRK
Parag A. Majmudar, MD, offered a number of suggestions for surgeons wishing to perform photorefractive keratectomy (PRK) during OSN New York 2018. For starters, said the associate professor of ophthalmology at Rush University Medical Center in Chicago, know your refractive limits. Specifically:
- Be aware of possible ectasia, which is seen more often in LASIK but can still occur in when performing PRK.
- Carefully select forme fruste keratoconus and keratoconus cases.
- The approximate cut off with modern lasers is -10D. “After that I start thinking about phakic IOLs,” said Dr. Majmudar. “My general rule of thumb is to limit stromal ablation to ~100 microns. You may need to adjust optical zone and match it to the pupil size.”
With regards to epithelial removal, he noted that the most important issue is time-related. “Longer removal times may result in dessication and variable outcomes.”
Manage postop pain with cold, BSS rinse and bandage contact lens. Use NSAIDs and oral narcotics judiciously.
Corneal infection is rare, occurring in 1 of every 5,000 cases. If you encounter one, said Dr. Majmudar, work it up and treat it like contact lens-related microbial keratitis. Specifically:
- If <2 mm, mid-periphery to limbus, consider empiric therapy with fluoroquinolone.
- If >2 mm and/or central/paracentral, consider scraping for culture and sensitivity and aggressive topical fortified antibiotics (cefazolin and tobramycin).
Corneal haze can also result. Treatment depends on severity and limitation of function, he explained. Specifically:
- No treatment required if not visually significant (some haze will clear spontaneously).
- If K’s are steepening and refraction shifting toward myopia, consider trial of steroids.
- Late-onset haze is more stubborn and may not clear with time or steroids.
- Consider mitomycin C 0.02% for 2 minutes.
Majmudar P. Surface ablation: Pearls and pitfalls. Talk presented at: OSN New York 2018; September 28-30, 2018; New York.