Intracranial electric field dosage and clinical response to electroconvulsive therapy in depressed patients.

BACKGROUND

Electroconvulsive therapy (ECT) provides rapid relief of depressive symptoms. However, the relationship between intracranial electric field (E-field) distribution, dosage, and antidepressant outcomes remains underexplored.

METHODS

Thirty patients with depressive episodes received bifrontal ECT. Clinical symptoms were assessed using the 17-Item Hamilton Rating Scale for Depression at baseline and post-ECT treatment. Magnetic resonance imaging was performed at baseline to calculate E-field strength and intracranial E-field dosage.

RESULTS

No significant associations were found between accumulated or average E-field dosage and overall antidepressant outcomes. However, significant associations were observed between antidepressant outcomes and E-field dosage during the initial ECT session in key brain regions, including the amygdala, anterior cingulate cortex, cerebellum, hippocampus, medial para-hippocampal cortex, postcentral gyrus, thalamus, and superior frontal lobe (P all < 0.05).

CONCLUSIONS

While no significant associations were found between cumulative or average E-field dosage and antidepressant outcomes of ECT, significant associations were observed between E-field dosage in key brain regions and antidepressant outcomes during the initial ECT session. These findings suggest that individualized ECT protocols, tailored to patient-specific neuroanatomy and E-field dosage in specific brain regions, may enhance ECT's therapeutic efficacy. Future research should explore personalized ECT protocols using computer-modeled E-field distribution and ECT parameters.