Efficacy of simple intravitreal gas injection for treating unclosed idiopathic macular holes after vitrectomy

Abstract Background This study aimed to observe the efficacy of simple intravitreal injection of C3F8 in the treatment of unclosed idiopathic macular holes (IMH) in patients after primary pars plana vitrectomy (PPV). Methods This was a retrospective clinical observational study. Patients diagnosed with unclosed IMH who underwent primary PPV combined with internal limiting membrane peeling (ILMP) and air tamponade were included in the study. Optical coherence tomography (OCT) at 1 week after PPV revealed unclosed IMH with the "cuff" sign and intraretinal cysts. The next day, the patients were treated by simple intravitreal injection of C3F8. All patients underwent best corrected visual acuity (BCVA), indirect ophthalmoscopy, fundus photography, and OCT before PPV and at 1 week, before and after intravitreal gas injection for 1 to 3 months. Results The minimum horizontal hole diameter (MHD) before PPV was 555.4 ± 104.8 µm, and that at 1 week after PPV was 335.1 ± 74.3 um, with statistically significant (t = 11.256, P < 0.001). The percentage of closed holes after air tamponade was 100%. The mean BCVA before PPV was 0.79 ± 0.26 logMAR (20/123), and that after air tamponade was 0.48 ± 0.19 logMAR (20/30) with statistical difference significantly (t = 5.303, P = 0.002). Conclusion For patients with enclosed IMH after primary PPV, if OCT reveals the "cuff" sign, retreatment can be performed through simple intravitreal gas injection. The method is simple, economical, practical, and effective.