A unified connectomic target for deep brain stimulation in obsessive-compulsive disorder

Multiple surgical targets for treating obsessive-compulsive disorder with deep brain stimulation (DBS) have been proposed. However, different targets may modulate the same neural network responsible for clinical improvement. We analyzed data from four cohorts of patients (N = 50) that underwent DBS to the anterior limb of the internal capsule (ALIC), the nucleus accumbens or the subthalamic nucleus (STN). The same fiber bundle was associated with optimal clinical response in cohorts targeting either structure. This bundle connected frontal regions to the STN. When informing the tract target based on the first cohort, clinical improvements in the second could be significantly predicted, and vice versa. To further confirm results, clinical improvements in eight patients from a third center and six patients from a fourth center were significantly predicted based on their stimulation overlap with this tract. Our results show that connectivity-derived models may inform clinical improvements across DBS targets, surgeons and centers. The identified tract target is openly available in atlas form.


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All studies must disclose on these points even when the disclosure is negative. Note that full information on the approval of the study protocol must also be provided in the manuscript. Based on these, a power analysis estimated an N of~25-30 to be necessary to perform a split-half prediction analysis. We were able to retrospectively collect a larger sample of N = 50 patients.

No data was excluded
Training and cross-validation of the model was performed on two large sub-cohorts (N = 22, N = 14) and tested / replicated on two smaller cohorts (N = 6, N = 8 patients). All attempts of replication were successful.
Participants were associated to training / test groups based on i) the center they were operated in and ii) the surgical target to which the electrodes had been implanted. Validations were performed on datasets that we obtained after the training period, by further collaborators (London, Madrid).
This was not a cohort study comparing groups, so Blinding does not apply. Rather, we estimated relationships between electrode placements and clinical improvements following OCD-DBS surgery at various surgical targets and DBS centers. Patients were retrospectively enrolled based on priorly published data.