Overview
This research explores the potential of retinal ganglion cells (RGCs), particularly intrinsically photosensitive RGCs (ipRGCs), as biomarkers for predicting response to transcranial magnetic stimulation (TMS) in treatment-resistant depression (TRD). We also aim to assess the impact of TMS treatment on RGCs and ipRGCs in TRD patients, investigating associations with clinical improvements and cognitive status. A clinical trial involving 44 patients with treatment-resistant depression (TRD) will be conducted. All participants will receive rTMS targeting the dorsolateral prefrontal cortex (DLPFC). Data will be collected pre- and post-intervention, as well as at a 2-month follow-up, using multiple outcome measures, including the post-illumination pupil response (PIPR). The project seeks to confirm the effectiveness of TMS and the potential of RGCs/ipRGCs as predictors of treatment response, thereby facilitating the development of personalized treatment strategies for TRD patients undergoing rTMS therapy.
Eligibility
Inclusion Criteria:
- Diagnosis of MDD, confirmed via the structured clinical interview;
- TRD type;
- Age between 18-65 years;
- Visual acuity of 20/32 or better.
Exclusion Criteria:
- Prior rTMS treatment;
- Contraindications for TMS;
- Psychiatric disorders other than MDD;
- Systemic diseases affecting the eyes (e.g., diabetes mellitus);
- Ocular conditions;
- Head injuries causing loss of consciousness;
- Current or past alcohol/substance dependence within 6 months;
- Neurodegenerative diseases;
- Major neurological illnesses;
- Use of medications affecting iris mechanics or the autonomic nervous system.


