To observe the dynamic characteristics of visual acuity after vitrectomy in different sizes of idiopathic macular hole, and analyze the influencing factors.

A retrospective study. From August 2016 to June 2018, 302 patients (302 eyes) with monocular idiopathic macular hole who underwent 25G vitrectomy combined with the internal limiting membrane peeling in Tianjin Eye Hospital were included in the study. There were 130 males and 172 females, with the mean age of 63.36±6.91 years. There were 158 left eyes and 144 right eyes. The logMAR BCVA was 1.13±0.45. The minimum diameter (422.92±211.73 μm) and basal diameter (835.47±366.42 μm) of macular hole and choroid thickness under fovea (244.84±60.68 μm) were measured by OCT. According to the minimum diameter, the holes were divided into small hole group (≤ 250 μm), middle hole group (>250 μm and ≤400 μm) and large hole group (>400 μm). The logMAR BCVA at 1, 3 and 6 months after surgery in 3 groups were observed. Two-factor repeated measure ANOVA was used to compare the visual acuity of the 3 groups. The generalized estimation equation (GEE) was used to analyze the influencing factors of postoperative visual recovery.

One month after surgery, all the holes were closed. One, 3 and 6 months after surgery, the logMAR BCVA were 0.33±0.25, 0.23±0.18, 0.16±0.17 in the small hole group; the logMAR BCVA were 0.46±0.25, 0.35±0.26, 0.27±0.28 in the middle hole group; the logMAR BCVA were 0.81±0.51, 0.61±0.48, 0.53±0.37 in the large hole group. Through repeated measurement variance analysis of two factors, it was found that there was an interaction between different groups and different time nodes (F=23.133, P <0.01). All data were segmented and one-way repeated measure ANOVA was performed. The results showed that there was a statistically significant difference in visual acuity between the small hole group and the middle hole group among preoperative and 1 month after surgery (P<0.05), while there was no statistically significant difference in visual acuity between 1, 3 and 6 months after surgery (P>0.05). In the large hole group, among preoperative, 1 months after surgery, 3 months after surgery, the visual acuity difference was statistically significant (P<0.05), while the visual acuity difference between 3 months after surgery and 6 months after surgery was not statistically significant (P>0.05). The results of GEE analysis showed that hole size (χ²=4.17, P=0.04), basal diameter (χ²=7.25, P=0.01), disease course (χ²=19.26, P=0.00), and choroid thickness (χ²=4.19, P=0.04) were the influencing factors of postoperative visual acuity.

After vitrectomy of macular holes of different sizes, the visual recovery trend is different. The visual recovery of small holes and middle holes is faster and basically restored at 1 month. The large holes requires a slow recovery process and stabilizes vision at 3 months. Hole size, basal diameter, course of disease and choroid thickness are the influencing factors of visual acuity recovery.

Retinal perforations/surgery; Vitrectomy; Root cause analysis; Longitudinal study