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Aim: Deep brain stimulation (DBS) is a safe and effective treatment option for people with refractory obsessive‐compulsive disorder (OCD). Yet our understanding of predictors of response and prognostic factors remains rudimentary, and long‐term comprehensive follow‐ups are lacking. We aim to investigate the efficacy of DBS therapy for OCD patients, and predictors of clinical response. Methods: Eight OCD participants underwent DBS stimulation of the nucleus accumbens (NAc) in an open‐label longitudinal trial, duration of follow‐up varied between 9 months and 7 years. Post‐operative care involved comprehensive fine tuning of stimulation parameters and adjunct multidisciplinary therapy. Results: Six participants achieved clinical response (35% improvement in obsessions and compulsions on the Yale Brown Obsessive Compulsive Scale (YBOCS)) within 6–9 weeks, response was maintained at last follow up. On average, the YBOCS improved by 45% at last follow up. Mixed linear modeling elucidated directionality of symptom changes: insight into symptoms strongly predicted (P = 0.008) changes in symptom severity during DBS therapy, likely driven by initial changes in depression and anxiety. Precise localization of DBS leads demonstrated that responders most often had their leads (and active contacts) placed dorsal compared to non‐responders, relative to the Nac. Conclusion: The clinical efficacy of DBS for OCD is demonstrated, and mediators of changes in symptoms are proposed. The symptom improvements within this cohort should be seen within the context of the adjunct psychological and biopsychosocial care that implemented a shared decision‐making approach, with flexible iterative DBS programming. Further research should explore the utility of insight as a clinical correlate of response. The trial was prospectively registered with the ANZCTR (ACTRN12612001142820). [ABSTRACT FROM AUTHOR]

Background and Purpose: In deep brain stimulation (DBS), accurate electrode placement is essential for optimizing patient outcomes. Localizing electrodes enables insight into therapeutic outcomes and development of metrics for use in clinical trials. Methods of defining anatomical targets have been described with varying accuracy and objectivity. To assess variability in anatomical targeting, we compare four methods of defining an appropriate target for DBS of the subthalamic nucleus for Parkinson's disease. Methods: The methods compared are direct visualization, red nucleus‐based indirect targeting, mid‐commissural point‐based indirect targeting, and automated template‐based targeting. This study assessed 226 hemispheres in 113 DBS recipients (39 females, 73 males, 62.2 ± 7.7 years). We utilized the electrode placement error (the Euclidean distance between the defined target and closest DBS electrode) as a metric for comparative analysis. Pairwise differences in electrode placement error across the four methods were compared using the Kruskal‐Wallis H‐test and Wilcoxon signed‐rank tests. Results: Interquartile ranges of the differences in electrode placement error spanned 1.18‐1.56 mm. A Kruskal‐Wallis H‐test reported a statistically significant difference in the median of at least two groups (H(5) = 41.052, p <.001). Wilcoxon signed‐rank tests reported statistically significant difference in two comparisons: direct visualization versus red nucleus‐based indirect, and direct visualization versus automated template‐based methods (T < 9215, p <.001). Conclusions: All methods were similarly discordant in their relative accuracy, despite having significant technical differences in their application. The differing protocols and technical aspects of each method, however, have the implication that one may be more practical depending on the clinical or research application at hand. [ABSTRACT FROM AUTHOR]

The article presents the discussion on deep brain stimulation (DBS) being an accepted therapy for treatment refractory-obsessive-compulsive disorder (TR-OCD) including hypomania, anxiety, deterioration of mood, and suicidal thoughts.

Objective: Deep brain stimulation (DBS) surgery is commonly performed with the patient awake to facilitate assessments of electrode positioning. However, awake neurosurgery can be a barrier to patients receiving DBS. Electrode implantation can be performed with the patient under general anesthesia (GA) using intraoperative imaging, although such techniques are not widely available. Electrophysiological features can also aid in the identification of target neural regions and provide functional evidence of electrode placement. Here we assess the presence and positional variation under GA of spontaneous beta and high-frequency oscillation (HFO) activity, and evoked resonant neural activity (ERNA), a novel evoked response localized to the subthalamic nucleus., Methods: ERNA, beta, and HFO were intraoperatively recorded from DBS leads comprising four individual electrodes immediately after bilateral awake implantation into the subthalamic nucleus of 21 patients with Parkinson's disease (42 hemispheres) and after subsequent GA induction deep enough to perform pulse generator implantation. The main anesthetic agent was either propofol (10 patients) or sevoflurane (11 patients)., Results: GA reduced the amplitude of ERNA, beta, and HFO activity (p < 0.001); however, ERNA amplitudes remained large in comparison to spontaneous local field potentials. Notably, a moderately strong correlation between awake ERNA amplitude and electrode distance to an "ideal" therapeutic target within dorsal STN was preserved under GA (awake: ρ = -0.73, adjusted p value [padj] < 0.001; GA: ρ = -0.69, padj < 0.001). In contrast, correlations were diminished under GA for beta (awake: ρ = -0.45, padj < 0.001; GA: ρ = -0.13, padj = 0.12) and HFO (awake: ρ = -0.69, padj < 0.001; GA: ρ = -0.33, padj < 0.001). The largest ERNA occurred at the same electrode (awake vs GA) for 35/42 hemispheres (83.3%) and corresponded closely to the electrode selected by the clinician for chronic therapy at 12 months (awake ERNA 77.5%, GA ERNA 82.5%). The largest beta amplitude occurred at the same electrode (awake vs GA) for only 17/42 (40.5%) hemispheres and 21/42 (50%) for HFO. The electrode measuring the largest awake beta and HFO amplitudes corresponded to the electrode selected by the clinician for chronic therapy at 12 months in 60% and 70% of hemispheres, respectively. However, this correspondence diminished substantially under GA (beta 20%, HFO 35%)., Conclusions: ERNA is a robust electrophysiological signal localized to the dorsal subthalamic nucleus subregion that is largely preserved under GA, indicating it could feasibly guide electrode implantation, either alone or in complementary use with existing methods.