AIM: To observe the effect of pars plana vitrectomy(PPV)internal limiting membrane(ILM)insertion and nerve growth factor(NGF)injection in the treatment of large idiopathic macular hole(IMH).

METHODS: This was a retrospective clinical study which included 16 patients(16 eyes)with large IMH diagnosed in the Affiliated Eye Hospital of Nanjing Medical University from May 2018 to May 2020. All patients were treated with PPV combined with ILM insertion and NGF injection and the follow-up period was at least 6mo. Macular hole closure rates, best-corrected visual acuity(BCVA)(LogMAR), and optical coherence tomography(OCT)findings including ellipsoid zone(EZ)and external limiting membrane(ELM)were analyzed, the complications were also observed postoperatively.

RESULTS: The BCVA was 1.15±0.21 before operation, and the follow-up of BCVA was 1.02±0.19 and 0.87±0.24 respectively at 3 and 6mo after operation(F=34.966, P<0.01); The BCVA was improved 3 and 6mo after operation(P<0.01), and the BCVA at 6mo after operation was better than that at 3mo(P<0.01). The closure rate of the MH was 100% and 11 eyes showed U-shaped closure in OCT(69%), 3 eyes were V-shaped closure(19%)and 2 eyes were irregular closure(13%). The BCVA of U-shaped closure group, V-shaped closure group and irregular closure group were 0.75±0.18, 1.1±0.19, and 1.20±0.00 respectively(F=6.937, P<0.01). The recovery of BCVA in U-shaped closure group was significantly better than that in V-shaped closure group and irregular closure group(P=0.027, 0.007). Six months after operation, 10 eyes(91%)of ELM and 7 eyes(64%)of ellipsoid zone resumed continuity in U-shaped closure group, 2 eyes(67%)of ELM and 1 eye(33%)of resumed continuity in V-shaped closure group. ELM and ellipsoidal zone were not recovered continuously in irregular closure group(P<0.05). During the follow-up period, we found no ocular or systemic complications.

CONCLUSION: PPV combined with ILM insertion and NGF injection is safe and effective in treating large IMH. The synergetic effect of NGF and ILM can obviously promote the closure of IMH, which is beneficial to the recovery of photoreceptor layer integrity and the improvement of visual function after operation.