Gamma Knife surgery anterior capsulotomy for severe and refractory obsessive-compulsive disorder

Gamma knife capsulotomy for intractable OCD: Neuroimage analysis of lesion size, location, and clinical response

Obsessive-compulsive disorder (OCD) affects 2-3% of the population. One-third of patients are poorly responsive to conventional therapies, and for a subgroup, gamma knife capsulotomy (GKC) is an option. We examined lesion characteristics in patients previously treated with GKC through well-established programs in Providence, RI (Butler Hospital/Rhode Island Hospital/Alpert Medical School of Brown University) and São Paulo, Brazil (University of São Paolo). Lesions were traced on T1 images from 26 patients who had received GKC targeting the ventral half of the anterior limb of the internal capsule (ALIC), and the masks were transformed into MNI space. Voxel-wise lesion-symptom mapping was performed to assess the influence of lesion location on Y-BOCS ratings. General linear models were built to compare the relationship between lesion size/location along different axes of the ALIC and above or below-average change in Y-BOCS ratings. Sixty-nine percent of this sample were full responders (≥35% improvement in OCD). Lesion occurrence anywhere within the targeted region was associated with clinical improvement, but modeling results demonstrated that lesions occurring posteriorly (closer to the anterior commissure) and dorsally (closer to the mid-ALIC) were associated with the greatest Y-BOCS reduction. No association was found between Y-BOCS reduction and overall lesion volume. GKC remains an effective treatment for refractory OCD. Our data suggest that continuing to target the bottom half of the ALIC in the coronal plane is likely to provide the dorsal-ventral height required to achieve optimal outcomes, as it will cover the white matter pathways relevant to change. Further analysis of individual variability will be essential for improving targeting and clinical outcomes, and potentially further reducing the lesion size necessary for beneficial outcomes.

Cost-effectiveness analysis of radiosurgical capsulotomy versus treatment as usual for treatment-resistant obsessive-compulsive disorder

OBJECTIVE

Stereotactic radiosurgical capsulotomy (SRS-C) is an effective neurosurgical option for patients with treatment-resistant obsessive-compulsive disorder (TROCD). Unlike other procedures such as deep brain stimulation and radiofrequency ablation, the cost-effectiveness of SRS-C for TROCD has not been investigated. The authors herein report the first cost-effectiveness analysis of SRS-C for TROCD.

METHODS

Using a decision analytic model, the authors compared the cost-effectiveness of SRS-C to treatment as usual (TAU) for TROCD. Treatment response and complication rates were derived from a review of relevant clinical trials. Published algorithms were used to convert Yale-Brown Obsessive Compulsive Scale scores into utility scores reflecting improvements in quality of life. Costs were approached from the healthcare sector perspective and were drawn from Medicare reimbursement rates and available healthcare economics data. A Monte Carlo simulation and probabilistic sensitivity analysis were performed to estimate the incremental cost-effectiveness ratio.

RESULTS

One hundred fifty-eight TROCD patients across 9 studies who had undergone SRS-C and had at least 36 months of follow-up were included in the model. Compared to TAU, SRS-C was more cost-effective, with an estimated incremental cost-effectiveness ratio of $28,960 per quality-adjusted life year (QALY) gained. Within the 3-year time horizon, net QALYs gained were greater in the SRS-C group than the TAU group by 0.27 (95% CI 0.2698-0.2702, p < 0.0001). At willingness-to-pay thresholds of $50,000 and $100,000 per QALY, the Monte Carlo simulation revealed that SRS-C was more cost-effective than TAU in 83% and 100% of iterations, respectively.

CONCLUSIONS

Compared to TAU, SRS-C for TROCD is more cost-effective under a range of possible cost and effectiveness values.

Gamma Knife radiosurgery for obsessive compulsive disorder

Gamma Knife radiosurgical capsulotomy has been performed for over 40 years as a rarely used surgical intervention for the treatment of obsessive-compulsive disorder. Over time, the procedure has evolved in many ways with most significant modifications being made in target location, number of isocenters and prescribed dose, subsequently producing changes in lesion size and geometry. Long-term clinical response data and adverse outcomes to the earlier empiric treatment parameters have resulted in shifting the target from its initial location within the midpoint of the anterior limb of internal capsule to a currently used point that includes its most ventral portion as well as the ventral striatum. This led to the contemporary Gamma Knife ventral capsulotomy procedure that focuses on ventral capsule/ventral striatum. Many of the early studies, despite demonstrating efficacy in some patients, were complicated by clinically relevant radiation-induced adverse effects. More recent studies have demonstrated strong efficacy with diminished adverse effects with well-placed lesions created at lower radiation doses. Advances in neuroimaging technology such as diffusion tensor imaging (DTI) based fiber tracking may provide further insight into precisely targeting of the ventral capsule/striatum based on patient-specific variations in white matter connectivity.

The future perspectives of psychiatric neurosurgery

The future of psychiatric neurosurgery can be viewed from two separate perspectives: the immediate future and the distant future. Both show promise, but the treatment strategy for mental diseases and the technology utilized during these separate periods will likely differ dramatically. It can be expected that the initial advancements will be built upon progress of neuroimaging and stereotactic targeting while surgical technology becomes adapted to patient-specific symptomatology and structural/functional imaging parameters. This individualized approach has already begun to show significant promise when applied to deep brain stimulation for treatment-resistant depression and obsessive-compulsive disorder. If effectiveness of these strategies is confirmed by well designed, double-blind, placebo-controlled clinical studies, further technological advances will continue into the distant future, and will likely involve precise neuromodulation at the cellular level, perhaps using wireless technology with or without closed-loop design. This approach, being theoretically less invasive and carrying less risk, may ultimately propel psychiatric neurosurgery to the forefront in the treatment algorithm of mental illness. Despite prominent development of non-invasive therapeutic options, such as stereotactic radiosurgery or transcranial magnetic resonance-guided focused ultrasound, chances are there will still be a need in surgical management of patients with most intractable psychiatric conditions.

Modern Gamma Knife radiosurgery for management of psychiatric disorders

Psychiatric disorders result in great suffering of affected patients, who often have rather limited treatment options. In cases refractory to standard medical and behavioral therapy, interventional procedures may be the only feasible solution. The authors experience with Gamma Knife bilateral cingulotomy for treatment-resistant major depression disorder (5 cases) and anorexia nervosa (6 cases), and bilateral anterior capsulotomy for severe obsessive-compulsive disorder (10 cases) shows that such radiosurgical techniques may be applied both effectively and safely. During post-treatment follow-up, the vast majority of patients demonstrated gradual reduction of psychiatric symptoms and improvement of the quality of life, which was confirmed by results of regular neuropsychological testing and imaging examinations. No major side effect was observed in any case. More active application of radiosurgery (using standardized technique) for management of mental illnesses in various Gamma Knife centers worldwide should be encouraged.

The Patient Lived-Experience of Ventral Capsulotomy for Obsessive-Compulsive Disorder: An Interpretive Phenomenological Analysis of Neuroablative Psychiatric Neurosurgery

Ventral Capsulotomy (VC) is a surgical intervention for treatment-resistant Obsessive-Compulsive Disorder (OCD). Despite clinical studies, little is known about patient perception and lived experience after neurosurgery for severe OCD. To examine the lived experiences of patients who have undergone VC for severe, treatment-resistant OCD through qualitative analysis. We conducted semi-structured interviews with six participants treated with VC for OCD. Interviews were analyzed using Interpretive Phenomenological Analysis. The following themes emerged: (1) After years of conventional treatments, patients felt neurosurgery was their “last hope” and described themselves as “desperate,” (2) While some described the surgery as a “supernatural experience,” patients also demonstrated understanding of the scientific procedure, its risks and potential benefits, (3) The surgical experience itself was positive or neutral, which was linked to trust in the clinical team, (4) Post-surgery, participants described months of heightened fear as they awaited lesion formation and functional improvement. (5) Patients consistently contextualized outcome in the context of their own life goals. Patients undergoing VC have positive views of this neurosurgical intervention, but psychiatric neurosurgical teams should anticipate patient discomfort with the time needed to achieve behavioral improvement following surgery and emphasize the importance of post-operative psychiatric care.

Behavioral disorders

Making lesions in the brain to relieve the distress of mental illness has had a checkered career due to a mixture of misuse and also caution about making permanent lesions in the brain where there was no physical abnormality. However, over the last 10 years a more flexible approach has developed. The method is still in its infancy and very little used. However, GKNS has been shown to be useful for OCD and also some cases of sever anxiety. It has been attempted for depression and anorexia nervosa but at present its role for these conditions remains to be determined.

Efficacy of Gamma Knife Radiosurgery in Refractory Obsessive-Compulsive Disorder: An Indian Experience

Background Obsessive-compulsive disorder (OCD) is a chronic debilitating psychiatric condition with adverse impact on patient's sociooccupational health. Refractoriness to pharmacotherapy and psychotherapy is not uncommon. Gamma Knife radiosurgery (GKRS) is the comprehensively used and reviewed treatment modality in refractory OCD worldwide. In India, the past two decades of increasing GKRS availability has failed to create the necessary local awareness of its usefulness in refractory OCD. Limited native literature deepens the problem.

Objective To analyze our experience with GKRS in refractory OCD, and report the safety and efficacy/long-term outcome in patients using the Yale–Brown Obsessive-Compulsive Scale (Y-BOCS).

Materials and Methods A retrospective review of patients receiving GKRS for refractory OCD between 2000 and 2020 was carried out. Case files of the eligible (n = 9) patients were reviewed for clinical, radiotherapeutic, and outcome data. Additionally, patients were contacted via telephone to enquire about their experiences, and to obtain retroactive consent for GKRS in June 2021. Information obtained was collated, computed, and analyzed.

Results Male-to-female sex ratio was 8:1. Mean age at the time of GKRS and mean duration of OCD prior to GKRS was 30.1 ± 9.4 and 10.2 ± 5.8 years, respectively. Mean baseline Y-BOCS score was 29.6 ± 4.7. Our first patient received cingulotomy, while the rest underwent anterior capsulotomy. Median margin dose (50% isodose) was 70 Gy. Also, 23.8 ± 7.7 was the mean Y-BOCS score at the last follow-up (median = 30 months). Overall, 44.4% patients showed full/partial response (≥25% reduction in Y-BOCS score) at the last follow-up. In anterior capsulotomy (eight patients), patients with moderate/severe OCD showed better response (4/5 responders) than those with extreme OCD (0/3 responders). Single case of cingulotomy resulted in no response (<25% reduction in Y-BOCS score). No adverse radiation effects were noted. Also, 55.6% patients gave retroactive consent telephonically.

Conclusion GKRS is a safe and effective noninvasive treatment modality for refractory OCD. Ventral anterior capsule is the preferred target. Maximum radiation doses of 120 to 160 Gy are well tolerated. Extremely severe OCD cases fared poorer. Proper awareness about the availability and efficacy of GKRS in refractory OCD is required in India.

Radiofrequency Lesioning for Movement and Psychiatric Disorders-Experience of 107 Cases

Background

Radiofrequency lesioning (RFL) though used since the 1950s, had been replaced by DBS in the 1990s. The availability of magnetic resonance-guided focused ultrasound for lesioning has renewed the interest in RFL.

Objective

This paper analysis RFL in contemporary Functional Neurosurgery for various indications and its outcome. Complication rates of RFL are compared with the same author’s experience of DBS.

Methods

One hundred and seven patients underwent RFL between 1998 and 2019. Indications included Parkinson’s Disease (PD), tremors, dystonia, and obsessive-compulsive disorders (OCD). The surgeries performed include thalamotomy (29), pallidotomy (49), subthalamotomy (23), and anterior capsulotomy/nucleus accumbens lesioning (6). Appropriate rating scales were used for preoperative and postoperative evaluations.

Results

There was a 25% recurrence rate of tremors for PD after thalamotomy. Writer’s cramp rating scale improved from a mean of 10.54–1.6 in task specific dystonia (TSD) patients, after thalamotomy. In PD patients, after pallidotomy, contralateral motor Unified Parkinson’s Disease Rating Scale (UPDRS) and dyskinesia scores, improved by 41 and 57%, respectively, at 1-year. Burke-Fahn-Marsden Dystonia Rating Scale in hemidystonia patients improved from 18.04 to 6.91, at 1-year. There was 32 and 31% improvement in total and motor UPDRS, respectively, in the subthalamotomy patients, at 2-year. All patients of OCD were in remission. There were three deaths in the pallidotomy group. Postoperative, dysarthria, confusion, hemiparesis, dyskinesia, and paraesthesia occurred in 12 patients, of which, 7 were transient.

Conclusion

RFL is a useful option in a select group of patients with tremors and dystonia. It is our preferred treatment option for TSD and OCD.

Deep brain stimulation versus ablative surgery for treatment-refractory obsessive-compulsive disorder: A meta-analysis

OBJECTIVE

Ablative surgery (ABL) and deep brain stimulation (DBS) are last-resort treatment options for patients suffering from treatment-refractory obsessive-compulsive disorder (OCD). The aim of this study was to conduct an updated meta-analysis comparing the clinical outcomes of the ablative procedures capsulotomy and cingulotomy and deep brain stimulation.

METHODS

We conducted a PubMed search to identify all clinical trials on capsulotomy, cingulotomy, and DBS. Random effects meta-analyses were performed on 38 articles with a primary focus on efficacy in reducing OCD symptoms as measured by a reduction in the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) score and the responder rate (≥35% reduction in Y-BOCS score).

RESULTS

With responder rates of 48% and 53% after 12-16 months and 56% and 57% at last follow-up for ABL and DBS, respectively, and large effect sizes in the reduction in Y-BOCS scores, both surgical modalities show effectiveness in treating refractory OCD. Meta-regression did not show a statistically significant difference between ABL and DBS regarding these outcomes. Regarding adverse events, a statistically significant higher rate of impulsivity is reported in studies on DBS.

CONCLUSION

This meta-analysis shows equal efficacy of ABL and DBS in the treatment of refractory OCD. For now, the choice of intervention should, therefore, rely on factors such as risk of developing impulsivity, patient preferences, and experiences of psychiatrist and neurosurgeon. Future research should provide more insight regarding differences between ABL and DBS and response prediction following direct comparisons between the surgical modalities, to enable personalized and legitimate choices between ABL and DBS.

Effectiveness and safety of neuroablation for severe and treatment-resistant obsessive-compulsive disorder: a systematic review and meta-analysis

Background

Several neuroablative procedures are available for severe and treatment-resistant obsessive-compulsive disorder (OCD), but limited knowledge about their relative clinical advantages and disadvantages poses obstacles for treatment decision-making.

Methods

We searched PubMed, Embase, Scopus, Web of Knowledge and the Cochrane Library for reports up to February 2019. We reviewed the literature on the effectiveness (assessed using the Yale-Brown Obsessive Compulsive Scale [Y-BOCS]) and safety of various neuroablative interventions for severe and treatment-resistant OCD.

Results

We included 23 studies involving 487 patients in the systematic review; 21 studies with 459 patients entered meta-analysis. Overall, neuroablation achieved a response rate (proportion of patients with ≥ 35% reduction in Y-BOCS) of 55%. Most of the adverse events (88.4%) were mild and transient. The top 3 adverse events were headache (14.9%), cognitive deficits (9.1%) and behaviour problems (8.1%). Severe or permanent adverse events included personality changes (2.3%) and brain edema or brain cyst (1.5%). The response rates associated with capsulotomy, limbic leucotomy and cingulotomy were 59% (95% confidence interval [CI] 54-65), 47% (95% CI 23-72) and 36% (95% CI 23-50), respectively. Interventions with different coverages of the dorsal part of the internal capsule were associated with different adverse-event profiles but were unlikely to modify clinical effectiveness.

Limitations

The level of evidence of most included studies was relatively low.

Conclusion

Ablative surgeries are safe and effective for a large proportion of patients with severe and treatment-resistant OCD. Among the available procedures, capsulotomy seemed to be the most effective. Further research is needed to improve clinical effectiveness and minimize risks.

An International Radiosurgery Research Foundation Multicenter Retrospective Study of Gamma Ventral Capsulotomy for Obsessive Compulsive Disorder

BACKGROUND

Obsessive compulsive disorder (OCD) across its full spectrum of severity is a psychiatric illness affecting ∼2% to 3% of the general population and results in significant functional impairment. There are few large patient series regarding Gamma ventral capsulotomy (GVC).

OBJECTIVE

To evaluate clinical outcomes of severe medically refractory OCD treated with GVC.

METHODS

This is an international, multicenter, retrospective cohort study. Forty patients with pre-GVC Yale-Brown Obsessive Compulsive Scale (Y-BOCS) scores ≥ 24 (indicating severe OCD) were included. GVC was performed with 1 or 2 isocenters with a median maximum dose of 135 Gy (range, 120-180 Gy). Patients were deemed "responders" to GVC if there was ≥35% reduction of follow-up Y-BOCS scores, and considered in remission if their Y-BOCS scores were ≤16. The median follow-up was 36 mo (range, 6-96 mo).

RESULTS

The median pre-SRS Y-BOCS score was 35 (range, 24-40). Eighteen patients (45%) were considered "responders," and 16 (40%) of them were in remission at their last follow-up. Nineteen patients (47.5%) remained stable with Y-BOCS of 33 (range, 26-36) following GVC, whereas 3 patients (7.5%) experienced worsening in Y-BOCS scores. Patients treated with 2 isocenters were more likely to have improvement in Y-BOCS score at 3 and 5 yr (P < .0005). Ten patients (25%) experienced post-GVC mood disturbance and neurological complications in 3 patients (7.5%). One patient developed radiation necrosis with edema that improved with steroids.

CONCLUSION

GVC serves as a reasonable treatment strategy for severe medical refractory OCD. Patients treated with 2 isocenters were more likely to have substantial improvement in OCD.

[Functional stereotactic radiosurgery: Indications and perspectives]

Stereotactic radiosurgery (SRS) is a non-invasive technique that enables to create brain focal lesions with a high precision and localization. Thus, functional brain disorders can be treated by SRS in case of pharmacoresistance or inoperability. To date, treatment of trigeminal neuralgia is the most described and known indication. Other indications will be developed in the future like movement disorders, refractory epilepsy, obsessive compulsive disorder and severe depression. We present here a review of actual and future indications of functional brain SRS with their level of evidence. All these SRS treatments have to be strictly conducted by trained teams with an excellent collaboration between radiation physicists, medical physicists, neurosurgeons, neurologists, psychiatrists and probably neuroradiologists.

The anterior limb of the internal capsule: Anatomy, function, and dysfunction

The last two decades have seen a re-emergence of neurosurgery for severe, refractory psychiatric diseases, largely due to the advent of more precise and safe operative techniques. Nevertheless, the optimal targets for these surgeries remain a matter of debate, and are often grandfathered from experiences in the late 20th century. To better explore the rationale for one target in particular - the anterior limb of the internal capsule (ALIC) - we comprehensively reviewed all available literature on its role in the pathophysiology and treatment of mental illness. We first provide an overview of its functional anatomy, followed by a discussion on its role in several prevalent psychiatric diseases. Given its structural integration into the limbic system and involvement in a number of cognitive and emotional processes, the ALIC is a robust target for surgical treatment of refractory psychiatric diseases. The advent of novel neuroimaging techniques, coupled with image-guided therapeutics and neuromodulatory treatments, will continue to enable study on the ALIC in mental illness.

Anterior capsulotomy for obsessive-compulsive disorder: a review of old and new literature

Over the last two decades, deep brain stimulation (DBS) has gained popularity as a treatment of severe and medically refractory obsessive-compulsive disorder (OCD), often using brain targets informed by historical lesional neurosurgical procedures. Paradoxically, the use of DBS in OCD has led some multidisciplinary teams to revisit the use of lesional procedures, especially anterior capsulotomy (AC), although significant aversion still exists toward the use of lesional neurosurgery for psychiatric disorders. This paper aims to review all literature on the use of AC for OCD to examine its effectiveness and safety profile.All publications on AC for OCD were searched. In total 512 patients were identified in 25 publications spanning 1961-2018. In papers where a Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score was available, 73% of patients had a clinical response (i.e., > 35% improvement in Y-BOCS score) and 24% patients went into remission (Y-BOCS score < 8). In the older publications, published when the Y-BOCS was not yet available, 90% of patients were deemed to have had a significant clinical response and 39% of patients were considered symptom free. The rate of serious complications was low.In summary, AC is a safe, well-tolerated, and efficacious therapy. Its underuse is likely a result of historical prejudice rather than lack of clinical effectiveness.

Results of Gamma Knife anterior capsulotomy for refractory obsessive-compulsive disorder: results in a series of 10 consecutive patients

OBJECTIVE

Obsessive-compulsive disorder (OCD) is a severe psychiatric condition. The authors present their experience with Gamma Knife radiosurgery (GKRS) in the treatment of patients with OCD resistant to any medical therapy.

METHODS

Patients with severe OCD resistant to all pharmacological and psychiatric treatments who were treated with anterior GKRS capsulotomy were retrospectively reviewed. These patients were submitted to a physical, neurological, and neuropsychological examination together with structural and functional MRI before and after GKRS treatment. Strict study inclusion criteria were applied. Radiosurgical capsulotomy was performed using two 4-mm isocenters targeted at the midputaminal point of the anterior limb of the capsule. A maximal dose of 120 Gy was prescribed for each side. Clinical global changes were assessed using the Clinical Global Impression (CGI) scale, Global Assessment of Functioning (GAF) scale, EQ-5D, Beck Depression Inventory (BDI), and State-Trait Anxiety Inventory (STAI). OCD symptoms were determined by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS).

RESULTS

Ten patients with medically refractory OCD (5 women and 5 men) treated between 2006 and 2015 were included in this study. Median age at diagnosis was 22 years, median duration of illness at the time of radiosurgery was 14.5 years, and median age at treatment was 38.8 years. Before GKRS, the median Y-BOCS score was 34.5 with a median obsession score of 18 and compulsion score of 17. Seven (70%) of 10 patients achieved a full response at their last follow-up, 2 patients were nonresponders, and 1 patient was a partial responder. Evaluation of the Y-BOCS, BDI, STAI-Trait, STAI-State, GAF, and EQ-5D showed statistically significant improvement at the last follow-up after GKRS. Neurological examinations were normal in all patients at each visit. At last follow-up, none of the patients had experienced any significant adverse neuropsychological effects or personality changes.

CONCLUSIONS

GKRS anterior capsulotomy is effective and well tolerated with a maximal dose of 120 Gy. It reduces both obsessions and compulsions, improves quality of life, and diminishes depression and anxiety.

Understanding gamma ventral capsulotomy: Potential implications of diffusion tensor image tractography on target selectivity

Background:

The role of tractography in gamma ventral capsulotomy (GVC) planning is still unclear. This paper aims to describe the spatial distribution of medial orbitofrontal cortex (OFC) and lateral OFC fibers passing through the anterior limb of the internal capsule (ALIC) and analyze quantitative tractography parameters that differentiate obsessive-compulsive disorder (OCD) individuals from other neurosurgery functional patients (morbid obesity and Parkinson’s disease [PD]).

Methods:

Twenty patients undergoing functional stereotactic procedures, between 2013 and 2016, were included in this study. OCD patients underwent GVC (single shot 150 Gy and 4-mm collimators). PD and morbid obesity patients were submitted to deep brain stimulation implants. Diffusion tensor image tractography was reconstructed using Brainlab Elements software (Brainlab AG, Munich, Germany).

Results:

Nine PD, six morbid obesity, and five OCD patients were included with a mean age of 65.4 ± 9.1, 41.0 ± 8.2, and 31.2 ± 5.5, respectively, which are statistically different from each other (P < 0.001). Fourteen patients (70%) were men. A total of 40 cerebral hemispheres were analyzed. Medial OFC fibers are localized more inferior in the ALIC than the lateral OFC fibers in all hemispheres, but the level of intersection and exact topography of fiber bundles are variable among individuals. Both medial and lateral OFC fiber tracts of PD and morbid obesity patients have lower volume than, respectively, medial and lateral counterparts of OCD patients (P < 0.001).

Conclusions:

Medial and lateral OFC tract fibers have a general standard distribution in the anterior internal capsule (lateral OFC higher than medial OFC fibers). There are differences between obesity, Parkinson, and OCD patients regarding fiber tract statistics.

Evolution of gamma knife capsulotomy for intractable obsessive-compulsive disorder

For more than half a century, stereotactic neurosurgical procedures have been available to treat patients with severe, debilitating symptoms of obsessive-compulsive disorder (OCD) that have proven refractory to extensive, appropriate pharmacological, and psychological treatment. Although reliable predictors of outcome remain elusive, the establishment of narrower selection criteria for neurosurgical candidacy, together with a better understanding of the functional neuroanatomy implicated in OCD, has resulted in improved clinical efficacy for an array of ablative and non-ablative intervention techniques targeting the cingulum, internal capsule, and other limbic regions. It was against this backdrop that gamma knife capsulotomy (GKC) for OCD was developed. In this paper, we review the history of this stereotactic radiosurgical procedure, from its inception to recent advances. We perform a systematic review of the existing literature and also provide a narrative account of the evolution of the procedure, detailing how the procedure has changed over time, and has been shaped by forces of evidence and innovation. As the procedure has evolved and adverse events have decreased considerably, favorable response rates have remained attainable for approximately one-half to two-thirds of individuals treated at experienced centers. A reduction in obsessive-compulsive symptom severity may result not only from direct modulation of OCD neural pathways but also from enhanced efficacy of pharmacological and psychological therapies working in a synergistic fashion with GKC. Possible complications include frontal lobe edema and even the rare formation of delayed radionecrotic cysts. These adverse events have become much less common with new radiation dose and targeting strategies. Detailed neuropsychological assessments from recent studies suggest that cognitive function is not impaired, and in some domains may even improve following treatment. We conclude this review with discussions covering topics essential for further progress of this therapy, including suggestions for future trial design given the unique features of GKC therapy, considerations for optimizing stereotactic targeting and dose planning using biophysical models, and the use of advanced imaging techniques to understand circuitry and predict response. GKC, and in particular its modern variant, gamma ventral capsulotomy, continues to be a reliable treatment option for selected cases of otherwise highly refractory OCD.

Gamma Ventral Capsulotomy in Intractable Obsessive-Compulsive Disorder

BACKGROUND

Despite the development of effective pharmacologic and cognitive behavioral treatments for obsessive-compulsive disorder (OCD), some patients continue to be treatment-refractory and severely impaired. Fiber tracts connecting orbitofrontal and dorsal anterior cingulate cortex with subcortical nuclei have been the target of neurosurgical lesions as well as deep brain stimulation in these patients. We report on the safety and efficacy of ventral gamma capsulotomy for patients with intractable OCD.

METHODS

Fifty-five patients with severely disabling, treatment-refractory OCD received bilateral lesions in the ventral portion of the anterior limb of the internal capsule over a 20-year period using the Leksell Gamma Knife. The patients were prospectively followed over 3 years with psychiatric, neurologic, and neuropsychological assessments of safety and efficacy, as well as structural neuroimaging.

RESULTS

Thirty-one of 55 patients (56%) had an improvement in the primary efficacy measure, the Yale-Brown Obsessive Compulsive Scale, of ≥35% over the 3-year follow-up period. Patients had significant improvements in depression, anxiety, quality of life, and global functioning. Patients tolerated the procedure well without significant acute adverse events. Five patients (9%) developed transient edema that required short courses of dexamethasone. Three patients (5%) developed cysts at long-term follow-up, 1 of whom developed radionecrosis resulting in an ongoing minimally conscious state.

CONCLUSIONS

Gamma Knife ventral capsulotomy is an effective radiosurgical procedure for many treatment-refractory OCD patients. A minority of patients developed cysts at long-term follow-up, 1 of whom had permanent neurological sequelae.

A study of novel bilateral thermal capsulotomy with focused ultrasound for treatment-refractory obsessive-compulsive disorder: 2-year follow-up

BACKGROUND

Recently, a new thermal lesioning approach using magnetic-resonance-guided focused ultrasound (MRgFUS) was introduced for the treatment of neurologic disorders. However, only 2 studies have used this approach for treatment-refractory obsessive-compulsive disorder (OCD), and follow-up was short-term. We investigated the efficacy and safety of bilateral thermal lesioning of the anterior limb of the internal capsule using MRgFUS in patients with treatment-refractory OCD and followed them for 2 years.

METHODS

Eleven patients with treatment-refractory OCD were included in the study. Clinical outcomes were evaluated using the Yale-Brown Obsessive Compulsive Scale, the Clinical Global Impression scale (including improvement and severity), the Hamilton Rating Scale for Depression (HAM-D) and the Hamilton Rating Scale for Anxiety (HAM-A) at 1 week and 1, 3, 6, 12 and 24 months following MRgFUS. Neuropsychological functioning, Global Assessment of Functioning and adverse events were also assessed.

RESULTS

After MRgFUS, Yale-Brown Obsessive Compulsive Scale scores decreased significantly across the 24-month follow-up period (mean ± standard deviation, 34.4 ± 2.3 at baseline v. 21.3 ± 6.2 at 24 months, p < 0.001). Scores on the Hamilton rating scales for depression and anxiety also significantly decreased from baseline to 24 months (HAM-D, 19.0 ± 5.3 v. 7.6 ± 5.3, p < 0.001; HAM-A, 22.4 ± 5.9 v. 7.9 ± 3.9, p < 0.001). Global Assessment of Functioning scores improved significantly (35.8 ± 4.9 at baseline v. 56.0 ± 10.3 at 24 months, p < 0.001) and Memory Quotient significantly improved, but other neuropsychological functions were unchanged. The side effects of MRgFUS included headache and vestibular symptoms, but these were mild and transient.

LIMITATIONS

The main limitations of this study were the small sample size and the open-label design.

CONCLUSION

Bilateral thermal lesioning of the anterior limb of the internal capsule using MRgFUS may improve obsessive-compulsive, depressive and anxiety symptoms in patients with treatment-refractory OCD, without serious adverse effects.

Functional Segmentation of the Anterior Limb of the Internal Capsule: Linking White Matter Abnormalities to Specific Connections

The anterior limb of the internal capsule (ALIC) carries thalamic and brainstem fibers from prefrontal cortical regions that are associated with different aspects of emotion, motivation, cognition processing, and decision-making. This large fiber bundle is abnormal in several psychiatric illnesses and a major target for deep brain stimulation. Yet, we have very little information about where specific prefrontal fibers travel within the bundle. Using a combination of tracing studies and diffusion MRI in male nonhuman primates, as well as diffusion MRI in male and female human subjects, we segmented the human ALIC into five regions based on the positions of axons from different cortical regions within the capsule. Fractional anisotropy (FA) abnormalities in patients with bipolar disorder were detected when FA was averaged in the ALIC segment that carries ventrolateral prefrontal cortical connections. Together, the results set the stage for linking abnormalities within the ALIC to specific connections and demonstrate the utility of applying connectivity profiles of large white matter bundles based on animal anatomic studies to human connections and associating disease abnormalities in those pathways with specific connections. The ability to functionally segment large white matter bundles into their components begins a new era of refining how we think about white matter organization and use that information in understanding abnormalities.SIGNIFICANCE STATEMENT The anterior limb of the internal capsule (ALIC) connects prefrontal cortex with the thalamus and brainstem and is abnormal in psychiatric illnesses. However, we know little about the location of specific prefrontal fibers within the bundle. Using a combination of animal tracing studies and diffusion MRI in animals and human subjects, we segmented the human ALIC into five regions based on the positions of axons from different cortical regions. We then demonstrated that differences in FA values between bipolar disorder patients and healthy control subjects were specific to a given segment. Together, the results set the stage for linking abnormalities within the ALIC to specific connections and for refining how we think about white matter organization in general.

Connectivity-based parcellation of the anterior limb of the internal capsule

The anterior limb of the internal capsule (ALIC) is an important locus of frontal-subcortical fiber tracts involved in cognitive and limbic feedback loops. However, the structural organization of its component fiber tracts remains unclear. Therefore, although the ALIC is a promising target for various neurosurgical procedures for psychiatric disorders, more precise understanding of its organization is required to optimize target localization. Using diffusion tensor imaging (DTI) collected on healthy subjects by the Human Connectome Project (HCP), we generated parcellations of the ALIC by dividing it according to structural connectivity to various frontal regions. We then compared individuals' parcellations to evaluate the ALIC's structural consistency. All 40 included subjects demonstrated a posterior-superior to anterior-inferior axis of tract organization in the ALIC. Nonetheless, subdivisions of the ALIC were found to vary substantially, as voxels in the average parcellation were accurately assigned for a mean of only 66.2% of subjects. There were, however, some loci of consistency, most notably in the region maximally connected to orbitofrontal cortex. These findings clarify the highly variable organization of the ALIC and may represent a tool for patient-specific targeting of neuromodulation. Hum Brain Mapp 38:6107-6117, 2017. © 2017 Wiley Periodicals, Inc.

Psychosurgery, ethics, and media: a history of Walter Freeman and the lobotomy

At the peak of his career, Walter J. Freeman II was a celebrated physician and scientist. He served as the first chairman of the Department of Neurology at George Washington University and was a tireless advocate of surgical treatment for mental illness. His eccentric appearance, engaging personality during interviews, and theatrical demonstrations of his surgical techniques gained him substantial popularity with local and national media, and he performed more than 3000 prefrontal and transorbital lobotomies between 1930 and 1960. However, poor patient outcomes, unfavorable portrayals of the lobotomy in literature and film, and increased regulatory scrutiny contributed to the lobotomy’s decline in popularity. The development of antipsychotic medications eventually relegated the lobotomy to rare circumstances, and Freeman’s reputation deteriorated. Today, despite significant advancements in technique, oversight, and ethical scrutiny, neurosurgical treatment of mental illness still carries a degree of social stigma.

This review presents a historical account of Walter Freeman’s life and career, and the popularization of the lobotomy in the US. Additionally, the authors pay special attention to the influence of popular literature and film on the public’s perception of psychosurgery. Aided by an understanding of this pivotal period in medical history, neurosurgeons are poised to confront the ethical and sociological questions facing psychosurgery as it continues to evolve.

A register-based 13-year to 43-year follow-up of 70 patients with obsessive-compulsive disorder treated with capsulotomy

OBJECTIVES

Little is known about the long-term medical status of patients with severe obsessive-compulsive disorder (OCD) undergoing capsulotomy, a neurosurgical last-resort treatment. The present study used national registers to identify all operated patients with OCD in Sweden and evaluated their long-term medical status, including mortality, hospital admissions and psychotropic medication after capsulotomy for OCD.

DESIGN

Register-based long-term follow-up cohort study.

PARTICIPANTS

We used the procedural and diagnostic codes in the Swedish National Patient Register to define the study population between 1970 and March 2013. Verification by manual review of medical records of the indication for surgery in those identified by the register yielded the final study cohort of 70 patients, followed 13-43 years after surgery. The sensitivity of the case selection method was 86%.

OUTCOME MEASURES

We studied hospitalisation 5 years before and after surgery. Mortality data were derived from the Causes of Death Register. The Prescribed Drug Register was used to study psychotropic drug utilisation.

RESULTS

By March 2013, 29 of the 70 patients were deceased. Their mean age at the time of death was 68 years (SD=14). Two patients had committed suicide and one had died of suspected suicide. Seventy per cent had been admitted to a psychiatric ward in the 5 years preceding surgery, and 84% in the first five postoperative years. Seventy-five per cent of those alive in 2012 were prescribed at least two psychotropic medications, often at high doses, the most common being antidepressants.

CONCLUSIONS

Malignant OCD has a poor long-term prognosis. Patients who are candidates for surgery should be informed that, while OCD symptoms may be ameliorated with surgery, they should not expect long-term freedom from medication and psychiatric care.

The Co-evolution of Neuroimaging and Psychiatric Neurosurgery

The role of neuroimaging in psychiatric neurosurgery has evolved significantly throughout the field's history. Psychiatric neurosurgery initially developed without the benefit of information provided by modern imaging modalities, and thus lesion targets were selected based on contemporary theories of frontal lobe dysfunction in psychiatric disease. However, by the end of the 20th century, the availability of structural and functional magnetic resonance imaging (fMRI) allowed for the development of mechanistic theories attempting to explain the anatamofunctional basis of these disorders, as well as the efficacy of stereotactic neuromodulatory treatments. Neuroimaging now plays a central and ever-expanding role in the neurosurgical management of psychiatric disorders, by influencing the determination of surgical candidates, allowing individualized surgical targeting and planning, and identifying network-level changes in the brain following surgery. In this review, we aim to describe the coevolution of psychiatric neurosurgery and neuroimaging, including ways in which neuroimaging has proved useful in elucidating the therapeutic mechanisms of neuromodulatory procedures. We focus on ablative over stimulation-based procedures given their historical precedence and the greater opportunity they afford for post-operative re-imaging, but also discuss important contributions from the deep brain stimulation (DBS) literature. We conclude with a discussion of how neuroimaging will transition the field of psychiatric neurosurgery into the era of precision medicine.

Dorsal anterior cingulotomy and anterior capsulotomy for severe, refractory obsessive-compulsive disorder: a systematic review of observational studies

OBJECT

The object of this study was to perform a systematic review, according to Preferred Reporting Items of Systematic reviews and Meta-Analyses (PRISMA) and Agency for Healthcare Research and Quality (AHRQ) guidelines, of the clinical efficacy and adverse effect profile of dorsal anterior cingulotomy compared with anterior capsulotomy for the treatment of severe, refractory obsessive-compulsive disorder (OCD).

METHODS

The authors included studies comparing objective clinical measures before and after cingulotomy or capsulotomy (surgical and radiosurgical) in patients with OCD. Only papers reporting the most current follow-up data for each group of investigators were included. Studies reporting results on patients undergoing one or more procedures other than cingulotomy or capsulotomy were excluded. Case reports and studies with a mean follow-up shorter than 12 months were excluded. Clinical response was defined in terms of a change in the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score. The authors searched MEDLINE, PubMed, PsycINFO, Scopus, and Web of Knowledge through October 2013. English and non-English articles and abstracts were reviewed.

RESULTS

Ten studies involving 193 participants evaluated the length of follow-up, change in the Y-BOCS score, and postoperative adverse events (AEs) after cingulotomy (n = 2 studies, n = 81 participants) or capsulotomy (n = 8 studies, n = 112 participants). The average time to the last follow-up was 47 months for cingulotomy and 60 months for capsulotomy. The mean reduction in the Y-BOCS score at 12 months’ follow-up was 37% for cingulotomy and 55% for capsulotomy. At the last follow-up, the mean reduction in Y-BOCS score was 37% for cingulotomy and 57% for capsulotomy. The average full response rate to cingulotomy at the last follow-up was 41% (range 38%–47%, n = 2 studies, n = 51 participants), and to capsulotomy was 54% (range 37%–80%, n = 5 studies, n = 50 participants). The rate of transient AEs was 14.3% across cingulotomy studies (n = 116 procedures) and 56.2% across capsulotomy studies (n = 112 procedures). The rate of serious or permanent AEs was 5.2% across cingulotomy studies and 21.4% across capsulotomy studies.

CONCLUSIONS

This systematic review of the literature supports the efficacy of both dorsal anterior cingulotomy and anterior capsulotomy in this highly treatment-refractory population. The observational nature of available data limits the ability to directly compare these procedures. Controlled or head-to-head studies are necessary to identify differences in efficacy or AEs and may lead to the individualization of treatment recommendations.

Bilateral thermal capsulotomy with MR-guided focused ultrasound for patients with treatment-refractory obsessive-compulsive disorder: a proof-of-concept study

Despite optimal pharmacotherapy and cognitive-behavioral treatments, a proportion of patients with obsessive-compulsive disorder (OCD) remain refractory to treatment. Neurosurgical ablative or nondestructive stimulation procedures to treat these refractory patients have been investigated. However, despite the potential benefits of these surgical procedures, patients show significant surgery-related complications. This preliminary study investigated the use of bilateral thermal capsulotomy for patients with treatment-refractory OCD using magnetic resonance-guided focused ultrasound (MRgFUS) as a novel, minimally invasive, non-cranium-opening surgical technique. Between February and May 2013, four patients with medically refractory OCD were treated with MRgFUS to ablate the anterior limb of the internal capsule. Patients underwent comprehensive neuropsychological evaluations and imaging at baseline, 1 week, 1 month and 6 months following treatment. Outcomes were measured with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), the Hamilton Rating Scale for Depression (HAM-D) and the Hamilton Rating Scale for Anxiety (HAM-A), and treatment-related adverse events were evaluated. The results showed gradual improvements in Y-BOCS scores (a mean improvement of 33%) over the 6-month follow-up period, and all patients showed almost immediate and sustained improvements in depression (a mean reduction of 61.1%) and anxiety (a mean reduction of 69.4%). No patients demonstrated any side effects (physical or neuropsychological) in relation to the procedure. In addition, there were no significant differences found in the comprehensive neuropsychological test scores between the baseline and 6-month time points. This study demonstrates that bilateral thermal capsulotomy with MRgFUS can be used without inducing side effects to treat patients with medically refractory OCD. If larger trials validate the safety, effectiveness and long-term durability of this new approach, this procedure could considerably change the clinical management of treatment-refractory OCD.

Ablative Limbic System Surgery: Review and Future Directions

The limbic system is a network of interconnected brain regions regulating emotion, memory, and behavior. Pathology of the limbic system can manifest as psychiatric disease, including obsessive-compulsive disorder and major depressive disorder. For patients with these disorders who have not responded to standard pharmacological and cognitive behavioral therapy, ablative surgery is a neurosurgical treatment option. The major ablative limbic system procedures currently used are anterior capsulotomy, dorsal anterior cingulotomy, subcaudate tractotomy, and limbic leucotomy. In this review, we include a brief history of ablative limbic system surgery leading up to its current form. Mechanistic justification for these procedures is considered in a discussion of the pathophysiology of psychiatric disease. We then discuss therapeutic efficacy as demonstrated by recent trials. Finally, we consider future directions, including the search for predictors of treatment response, the development of more precise targeting methods, and the use of advances in neuroimaging to track treatment response.

Deep brain stimulation versus anterior capsulotomy for obsessive-compulsive disorder: a review of the literature

Obsessive-compulsive disorder (OCD) is a chronic and debilitating psychiatric condition. Traditionally, anterior capsulotomy (AC) was an established procedure for treatment of patients with refractory OCD. Over recent decades, deep brain stimulation (DBS) has gained popularity. In this paper the authors review the published literature and compare the outcome of AC and DBS targeting of the area of the ventral capsule/ventral striatum (VC/VS) and nucleus accumbens (NAcc).

Patients in published cases were grouped according to whether they received AC or DBS and according to their preoperative scores on the Yale-Brown Obsessive-Compulsive Scale (YBOCS), and then separated according to outcome measures: remission (YBOCS score < 8); response (≥ 35% improvement in YBOCS score); nonresponse (< 35% improvement in YBOCS score); and unfavorable (i.e., worsening of the baseline YBOCS score).

Twenty studies were identified reporting on 170 patients; 62 patients underwent DBS of the VC/VS or the NAcc (mean age 38 years, follow-up 19 months, baseline YBOCS score of 33), and 108 patients underwent AC (mean age 36 years, follow-up 61 months, baseline YBOCS score of 30). In patients treated with DBS there was a 40% decrease in YBOCS score, compared with a 51% decrease for those who underwent AC (p = 0.004). Patients who underwent AC were 9% more likely to go into remission than patients treated with DBS (p = 0.02). No difference in complication rates was noted.

Anterior capsulotomy is an efficient procedure for refractory OCD. Deep brain stimulation in the VC/VS and NAcc area is an emerging and promising therapy. The current popularity of DBS over ablative surgery for OCD is not due to nonefficacy of AC, but possibly because DBS is perceived as more acceptable by clinicians and patients.

Neurological applications of transcranial high intensity focused ultrasound

Advances in transcranial MRI-guided focused ultrasound have renewed interest in lesioning procedures in functional neurosurgery with a potential role in the treatment of neurological conditions such as chronic pain, brain tumours, movement disorders and psychiatric diseases. While the use of transcranial MRI-guided focused ultrasound represents a new innovation in neurosurgery, ultrasound has been used in neurosurgery for almost 60 years. This paper reviews the major historical milestones that have led to modern transcranial focused ultrasound and discusses current and evolving applications of ultrasound in the brain.

The Promise of Neurotechnology in Clinical Translational Science

Neurotechnology is broadly defined as a set of devices used to understand neural processes and applications that can potentially facilitate the brain's ability to repair itself. In the past decade, an increasingly explicit understanding of basic biological mechanisms of brain-related illnesses has produced applications that allow a direct yet noninvasive method to index and manipulate the functioning of the human nervous system. Clinical scientists are poised to apply this technology to assess, treat, and better understand complex socioemotional processes that underlie many forms of psychopathology. In this review, we describe the potential benefits and hurdles, both technical and methodological, of neurotechnology in the context of clinical dysfunction. We also offer a framework for developing and evaluating neurotechnologies that is intended to expedite progress at the nexus of clinical science and neural interface designs by providing a comprehensive vocabulary to describe the necessary features of neurotechnology in the clinic.

Cranial stereotactic radiosurgery: current status of the initial paradigm shifter

The concept of stereotactic radiosurgery (SRS) was first described by Lars Leksell in 1951. It was proposed as a noninvasive alternative to open neurosurgical approaches to manage a variety of conditions. In the following decades, SRS emerged as a unique discipline involving a collegial partnership among neurosurgeons, radiation oncologists, and medical physicists. SRS relies on the precisely guided delivery of high-dose ionizing radiation to an intracranial target. The focused convergence of multiple beams yields a potent therapeutic effect on the target and a steep dose fall-off to surrounding structures, thereby minimizing the risk of collateral damage. SRS is typically administered in a single session but can be given in as many as five sessions or fractions. By providing an ablative effect noninvasively, SRS has altered the treatment paradigms for benign and malignant intracranial tumors, functional disorders, and vascular malformations. Literature on extensive intracranial radiosurgery has unequivocally demonstrated the favorable benefit-to-risk profile that SRS affords for appropriately selected patients. In a departure from conventional radiotherapeutic strategies, radiosurgical principles have recently been extended to extracranial indications such as lung, spine, and liver tumors. The paradigm shift resulting from radiosurgery continues to alter the landscape of related fields.

Neurocircuitry of limbic dysfunction in anorexia nervosa

Anorexia Nervosa (AN) is a serious psychiatric condition marked by firmly entrenched and maladaptive behaviors and beliefs about body, weight and food, as well as high rates of psychiatric comorbidity. The neural roots of AN are now beginning to emerge, and appear to be related to dysfunctional, primarily limbic, circuits driving pathological thoughts and behaviors. As a result, the significant physical symptoms of AN are increasingly being understood at least partially as a result of abnormal or dysregulated emotional processing. This paper reviews the nature of limbic dysfunction in AN, and how structural and functional imaging has implicated distinct emotional and perceptual neural circuits driving AN symptoms. We propose that top-down and bottom-up influences converge on key limbic modulatory structures, such as the subcallosal cingulate and insula, whose normal functioning is critical to affective regulation and emotional homeostasis. Dysfunctional activity in these structures, as is seen in AN, may lead to emotional processing deficits and psychiatric symptoms, which then drive maladaptive behaviors. Modulating limbic dysregulation may therefore be a potential treatment strategy in some AN patients.