Transcranial magnetic stimulation-based neuroplasticity in the treatment of amblyopia

In recent years, repetitive transcranial magnetic stimulation (rTMS) has shown positive clinical effects in improving neuroplasticity by modulating cortical neural activity, particularly the functional connectivity of visual-related brain regions. This research was aimed to investigate the effects of rTMS on visual function in adult amblyopia and to assess changes in brain neuronal activity before and following remedy using resting-state functional magnetic resonance imaging (rs-fMRI).

A total of 148 patients with anisometropic amblyopia were enrolled and randomly divided into: intraocular lens (ICL) group and ICL+rTMS group, with 74 cases in each group. All patients received detailed perioperative care. Best-corrected visual acuity (BCVA) and random dot stereopsis were assessed using the Vision Perception Test System before treatment and 3 months following remedy, and brain functional status was evaluated using rs-fMRI.

As against pre-treatment levels, both ICL group and ICL+rTMS group suggested visible improvements in BCVA and random dot stereopsis 3 months following remedy, with ICL+rTMS group exhibiting better outcomes than ICL group (P < 0.05). The rs-fMRI revealed distinct patterns of neural plasticity: ICL group exhibited an increase in the ALFF of the ipsilateral frontal lobe, while ICL+rTMS group showed a decrease in the ALFF of the same-side cerebellum (P < 0.05). Compared to ICL alone, the combination of rTMS and ICL significantly reduced the ReHo in the ipsilateral frontal lobe and superior frontal gyrus, decreased the fALFF in the contralateral temporal lobe, and increased the fALFF in the contralateral occipital lobe (P < 0.05).

The application of rTMS to directly regulate neural plasticity provides a non-invasive and precise treatment method. Compared with traditional therapies, rTMS can more effectively promote the reorganization of visual cortex function in amblyopia patients, improve treatment efficacy, and have fewer side effects, thus having high clinical application potential.

rTMS can effectively improve visual function in adult amblyopia patients by modulating neuronal activity and enhancing visual cortical neuroplasticity to correct the interocular excitation differences and exert therapeutic effects.