To evaluate the effect of Transvitreal optic Neurotomy (TON) and vitreopapillary traction release (VTR) of ONH in patients with NAION

In this randomized clinical trial, patients with the diagnosis of NAION in the acute phase and best corrected visual acuity of less than 20/200 were included. Patients were randomized in two groups and underwent TON in one group and vitreopapillary traction release after standard 3 port vitrectomy. The primary outcome measure was best-corrected visual acuity (BCVA) and secondary outcome measures were mean deviation (MD) of the visual field and retinal nerve fiber layer thickness (RNFLT) measured by optical coherence tomography (OCT).

10 patients and 9 patients were included in VTR and TON group respectively by randomization. 18 patients matched for baseline BCVA and MD were included as the control group. Mean BCVA at VTR group improved significantly from 1.84 ± 0.5 at baseline to 1.29 ± 0.67, 0.93 ± 0.53 and 0.77 ± 0.47 at 1, 3 and 6 months respectively. the corresponding values for TON were 1.73 ± 0.53 at the baseline which reached 1.04 ± 0.65, 0.64 ± 0.28 and 0.61 ± 0.26 at the same follow-up visit times. In the control group, the Mean BCVA improved from 1.6 ± 0.58 at the baseline to 1.03 ± 0.29, 1.00 ± 0.32 and 0.83 ± 0.33 at 1, 3 and 6 months postoperatively. There was no significant statistical difference between the three study groups. In VTR, mean MD was -22.61 ± 6.61 at baseline which improved to – 20.7 ± 6.36, -17.3 ± 5.77, -15.06 ± 3.2 at 1,3 and 6 months, respectively. In TON, the Corresponding values were -20.66 ± 6.2 at baseline which reached to -19.41 ± 6.3, -17.7 ± 4.68, -16.94 ± 6.82 at 1,3 and 6 months, respectively. Both interventions resulted in more MD improvement in patients compared with the control group at the end of month 6.Ps= 0.006 and 0.043. Considering RNFLT, optic disc edema showed faster resolution in both intervention groups

VTR and TON show promising results in the treatment of NAION in the acute phase.