Anterior capsulotomy for treatment-refractory obsessive-compulsive disorder: a systematic review of clinical outcomes in 407 patients

Background

Obsessive-Compulsive Disorder is a chronic and disabling neuropsychiatric condition characterised both by intrusive thoughts and repetitive behaviours, associated with dysfunction in cortico-striato-thalamo-cortical circuits. Although first-line treatments, including selective serotonin reuptake inhibitors and cognitive-behavioural therapy, are effective for many patients, up to 40–60% remain treatment-refractory, posing a significant clinical challenge. For these severe cases, Anterior Capsulotomy has been employed as a neurosurgical intervention targeting the anterior limb of the internal capsule to modulate dysfunctional neural connectivity. However, evidence regarding its efficacy and safety remains heterogeneous and has not been comprehensively synthesised.

Aims

This study aimed to systematically synthesise the available evidence regarding the clinical efficacy and safety of anterior capsulotomy in patients with treatment-refractory OCD, with a focus on treatment response rates and adverse outcomes.

Methods

A systematic review was conducted using PubMed, LILACS, and the Cochrane Library in accordance with PRISMA guidelines. The search strategy combined the terms “anterior capsulotomy,” “obsessive compulsive disorder,” and “neurosurgery.” Two independent reviewers screened records using Rayyan software, with disagreements resolved by consensus. Duplicate records and review articles were excluded. Eligible studies included original research reporting clinical outcomes in patients undergoing anterior capsulotomy for refractory OCD. Extracted data included sample size, demographic characteristics, duration of follow-up, clinical response rates, and reported adverse events. Clinical response was defined as a reduction of at least 35% in Yale-Brown Obsessive Compulsive Scale (Y-BOCS) scores. A descriptive statistical approach was adopted, with pooled proportions calculated for treatment response. Due to significant methodological heterogeneity across studies, a formal meta-analysis could not be performed.

Results

A total of 114 records were identified, of which 22 studies met inclusion criteria, encompassing 407 patients. Across studies, anterior capsulotomy was consistently associated with clinically meaningful reductions in OCD symptom severity. Overall, 71.7% (n = 292) of patients achieved a clinically significant response according to Y-BOCS criteria. Although study designs, surgical techniques, and follow-up durations varied, the overall direction of effect was largely consistent. Reported adverse events included neuropsychiatric symptoms such as apathy, reduced motivation, and impaired decision-making, generally affecting a minority of patients. However, the reporting of adverse events and long-term outcomes was inconsistent and often limited, restricting the ability y to draw firm conclusions about safety.

Conclusions

Anterior capsulotomy appears to be associated with substantial rates of clinical improvement in patients with severe, treatment-refractory OCD and may represent a valuable therapeutic option in carefully selected cases. Nevertheless, the current evidence base is limited by heterogeneity, a predominance of observational study designs, and insufficient standardisation in outcome reporting. These limitations necessitate cautious interpretation of the findings. Future research should prioritise well-designed prospective and controlled studies to better characterise long-term efficacy and safety, optimise patient selection criteria, and clarify the role of anterior capsulotomy within modern, multimodal treatment strategies for OCD.

References

No references.