Closure procedure success higher in eyes with small macular holes

A smaller macular hole size prior to closure surgery leads to better visual acuity (VA) outcomes, reports a new study. The diameter threshold for what constitutes a large hole seems to be around 500 µm, beyond which closure success declines.

Researchers conducted a database study of 1,483 hole-closure operations. Only primary macular hole procedures treated with a gas or air tamponade were eligible. The study outcomes were the probability of a postoperative VA ≤0.30 logMAR, and hole closure. Multivariable logistic regression was used to calculate for the estimates.

Patients undergoing operation were predominantly female (71.1 percent) who were, on average, younger their male counterparts (p<0.001). Macular holes were also slightly, but significantly, larger in the female patients (414.8 vs 366.3 µm; p<0.001). Symptom duration prior to surgery did not differ between sexes.

The average hole size was 400 µm, and sizes were approximately distributed around this mean, with a standard deviation of 156 µm. Nearly half (49.5 percent) of the eyes had a hole size falling above the mean, while only 16.3 percent had sizes <250 µm.

Procedure outcomes were known in 1,253 of the operations, in which 95.7 percent (n=1,199) closure was successfully achieved. Visual outcome analysis was possible for 1,056 eyes, 46.2 percent of which achieved VA ≥0.30 logMAR.

Success probability was affected by the size of the macular hole. Those <400 µm in diameter had a failure rate of just 1.1 percent, while those ≥600 µm failed 13.5 percent of the time. A hole diameter of 500 µm appeared to be a good threshold for determining success: smaller holes had a 1.5- to 2.5-percent failure rate, while closure of wider holes failed 10.2- to 17.6-percent of the time.