Effect of internal limiting membrane peeling on normal retinal function evaluated by microperimetry-3

Abstract

Background: To evaluate the effect of internal limiting membrane (ILM) peeling surrounding macular holes (MH) for the function of retina by microperimetry-3(MP-3).

Methods: This is a prospective, cohort study which included patients with MHs who were treated by 23-gauge 3-port pars plana vitrectomy and ILM peeling with air tamponade. Color fundus photography, retinal optical coherence tomography and MP-3 were performed 1 week before, 1 and 4 months after the operation. In MP-3 examination, a customized follow-up pattern with 45 spots in the central 8° visual field was used. The spots corresponding to the retina surrounding macular holes were selected for comparison of pre- and post-operative function.

Results: We incuded 44 eyes of 44 patients with best corrected visual acuity (BCVA) of 1.06 ± 0.40 (logMAR). All eyes achieved an anatomical success at 4 months. BCVA significantly improved at 1 month (0.53 ± 0.30, P < 0.01) and 4 months (0.31 ± 0.24, P < 0.01), respectively. Mean retinal sensitivity (MRS, dB) of the retina surrounding macular hole was 23.46 ± 3.01 dB at baseline, and significantly increased at 1 month (26.25 ± 2.31 dB, u = - 4.88, P < 0.01) and 4 months (27.14 ± 2.45 dB, t = - 6.29, P < 0.01). Patients with increased MRS are significantly younger than those with deceased MRS (59.72 ± 3.22 years vs. 65.60 ± 8.19 years, P < 0.01). After ILM peeling, the increasing extent of MRS was significantly higher in inferior and nasal retina than in superior and temporal retina at 1 and 4 months (P < 0.05).

Conclusion: ILM peeling in normal retina will not decrease the retinal function in a short-term after surgery.

Keywords: Internal limiting membrane peeling; Macular hole; Microperimetry-3; Retinal sensitivity; Vitrectomy.

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1

A customized pattern was used in 8° of the visual field, with 45 spots

Fig. 2

The area was divided into four regions, superior nasal (point A1–8), inferior nasal (point B1–8), inferior temporal (point C1–8), and superior temporal (point D1–8). When calculating, the points located on X-axis or Y-axis were excluded. For example, when comparing the retinal sensitivity between superior and inferior retina, the points located on X-axis (point B1,2,3 and D1,2,3) were excluded. In the same way, when comparing the retinal sensitivity between nasal and temporal retina, the points located on Y-axis (point A1,2,3 and C1,2,3) were excluded

Fig. 3

Left eye of a Chinese patient (60–70 years old) with a macular hole (MH) treated by pars plana vitrectomy with ILM peeling. (left) Preoperative; (right) Postoperative; The examiner was asked to fix the fixation target to the central of MHs as much as possible. Follow-up pattern was used to ensure the selected dots located on the same position whether in preoperative or in postoperative examination. When calculating, we only choose 28 points in the outer ring zone (between the two black circles) instead of all 45 points, which located in the normal retina, and the area covered by MH was excluded

Fig. 4

Left eye of a Chinese patient (60–70 years old) with a huge macular hole (MH). Points a, b, c, d was excluded for the distance from these points to the margin of MH was less than 0.5°. When calculated for this patient, we only chose 24 points in the outer ring zone