Eyeworld

86 | EYEWORLD | JUNE 2022 C ORNEA appearing corneas on slit lamp examination. Additionally, in 28 of those 58 eyes, the most common presumed mechanism of injury was clear corneal cataract surgery. "In the pathology of recurrent corneal erosion, the classic teaching is that it's typically caused by accidental trauma. The injury disrupts the epithelium and scrapes it off the basement membrane underneath, then as the eye heals back, it may not heal with good adhesion to the sub-floor," Dr. Kim said. "It has this loose attach- ment, and anything that can pull the epithelium off, like dry eye or nocturnal lagophthalmos, can cause the eyelid and epithelium to stick togeth- er, and upon opening the eyelid, the epithelium can separate abruptly and cause sharp pain." He added that it requires a paradigm shift to think that clear corneal cataract surgery can be one of the causes of these corneal erosions. "We don't understand the disease process fully," Dr. Kim said. "But among those 28 eyes [in the retrospective chart review], 20 of them only de- veloped symptoms after their cataract surgery." Furthermore, when sweeping the cornea, the erosions were right over the cataract incisions. For those questioning "how do you know you're not causing trauma with the corneal sweep test?" Dr. Kim said he further looked at 40 eyes of 20 patients. "We excluded every- thing," he said. There was no prior corneal surgery, no prior corneal injury, no history of contact lens wear, no history of diabetes or ocular surface disease. When looking at this group, 38 of the 40 eyes had completely normal corneas when their corneas were swept. None of the 40 had complications from the sweep maneuver, and none had symptoms after the numbing drops wore off. Dr. Kim said that 2 of the 40 had a small 2–3 mm area of loose epithe- lium along the superior limbus, and he admits it's hard to know what that means. "This could be a form of forme fruste epithelial basement membrane disease. The truth is, we don't know, and further research is needed." As a result of the new technique and in- strument, Dr. Kim has created a completely new classification for these patients, which he refers to as "occult corneal erosion." This term is used because the erosions were missed by standard diagnostic techniques. "I think a lot more research needs to be done, and I think there's a lot more to learn about this disease," he said. He recognized that many might still question this technique and the conclusions drawn, specifically noting that there might be a question of how you know that the loose epithelium that is found with the corneal sweep technique is, in fact, a recurrent corneal erosion. continued on page 88 continued from page 85 The Kim Corneal Sweeper is oriented with the round profile in view. The tip is rotated 90 degrees with the flat profile in view. Note the tapered edges for a smooth design and thin profile, which enables a clear view of the cornea during the sweep maneuver.

• Cover