Background and Objective: The therapeutic outcomes of amblyopia after the age range of 8-10 years are poor, and amblyopia in older individuals is resistant to treatment. Repetitive Transcranial Magnetic Stimulation (rTMS), among the efforts intended to modulate cortical excitability in the treatment of psychiatric disorders, has been believed to be associated with a specific disease. This study aimed to determine the effect of rTMS on the treatment of treatment-resistant amblyopia in adult patients.
Methods: This clinical trial was conducted on 16 patients (12 males and 4 females) with unilateral amblyopia, with a mean age of 30±5 years referring to the clinics of Khatam al-Anbia Eye Hospital, Mashhad, Iran, during 2016-17. Patients were randomly selected from those with unilateral amblyopia (refractive, strabismic, or mixed) who had not responded to conventional treatments (patching or penalization). The healthy eye was considered a control. The therapeutic intervention consisted of four rTMS sessions at two-week intervals. Visual acuity and contrast sensitivity were measured and compared three times: Before the intervention, at the first session of intervention, and at the fourth session of intervention.
Results: The mean visual acuity at baseline (0.36±0.19) was not significantly different compared to the first treatment session (0.41±0.1); however, a significant increase was observed compared to the fourth session (0.45±0.23) (P<0.05). The mean contrast sensitivity at baseline (2.02±0.74) was not significantly different compared to the first (1.97±0.63) and the fourth (2.16±0.94) treatment sessions.
Conclusion: In most follow-ups, improvement in contrast was not observed in patients with treatment-resistant amblyopia at older ages using rTMS. Only an improvement in visual acuity was observed in the last follow-up compared to the baseline in the patient group.