Bilateral Anterior Cingulotomy for Refractory Obsessive-Compulsive Disorder: Long-Term Follow-Up Results

Long-term follow-up of deep brain stimulation for refractory obsessive-compulsive disorder

We studied the 2-year outcome of deep-brain stimulation at the ventral anterior limb of the internal capsule and ventral striatum for 4 patients with treatment-resistant OCD. There were prolonged improvement of obsessive-compulsive symptoms and depressive symptoms along with notable functional improvement in all participants with no battery depletion.

Deep brain stimulation for intractable psychiatric disorders

Deep brain stimulation (DBS) has virtually replaced ablative neurosurgery for use in medication-refractory movement disorders. DBS is now being studied in severe psychiatric conditions, such as treatment-resistant depression (TRD) and intractable obsessive-compulsive disorder (OCD). Effects of DBS have been reported in ∼100 cases of OCD and ∼50 cases of TRD for seven (five common) anatomic targets. Although these published reports differ with respect to study design and methodology, the overall response rate appears to exceed 50% in OCD for some DBS targets. In TRD, >50% of patients responded during acute and long-term bilateral electrical stimulation in a different target. DBS was generally well tolerated in both OCD and TRD, but some unique, target- and stimulation-specific adverse effects were observed (e.g., hypomania). Further research is needed to test the efficacy and safety of DBS in psychiatric disorders, compare targets, and identify predictors of response.

Deep brain stimulation: technology at the cutting edge

Deep brain stimulation (DBS) surgery has been performed in over 75,000 people worldwide, and has been shown to be an effective treatment for Parkinson's disease, tremor, dystonia, epilepsy, depression, Tourette's syndrome, and obsessive compulsive disorder. We review current and emerging evidence for the role of DBS in the management of a range of neurological and psychiatric conditions, and discuss the technical and practical aspects of performing DBS surgery. In the future, evolution of DBS technology may depend on several key areas, including better scientific understanding of its underlying mechanism of action, advances in high-spatial resolution imaging and development of novel electrophysiological and neurotransmitter microsensor systems. Such developments could form the basis of an intelligent closed-loop DBS system with feedback-guided neuromodulation to optimize both electrode placement and therapeutic efficacy.

Mental health legislation and psychiatric treatments in NSW: electroconvulsive therapy and deep brain stimulation

OBJECTIVE

The aim of this paper is to discuss the restriction of electroconvulsive therapy (ECT) to the treatment of psychiatric disorders and the prohibition of psychosurgery and deep brain stimulation (DBS) in the NSW Mental Health Act 2007 (MHA), and to examine these restrictions from clinical and human rights perspectives.

METHOD

Sections of the NSW MHA regulating the use of ECT, psychosurgery and DBS were reviewed. These were compared with corresponding regulations in mental health legislation in other Australian states. Reasons for discrepancies were explored.

RESULTS

Restrictions in the MHA on the use of ECT, psychosurgery and DBS are not in line with current clinical evidence of their efficacy and safety. The prohibitions aim to ensure safeguards are in place but the legislation fails to balance these objectives with the potential clinical benefit offered by these treatments.

CONCLUSIONS

By imposing restrictions which are not justifiable in terms of the clinical evidence available, the MHA discriminates against those with neurological disorders responsive to psychiatric treatments, and those with psychiatric disorders who would benefit from the development of DBS as a treatment.

Deep brain stimulation for psychiatric disorders

BACKGROUND

Deep brain stimulation (DBS), an established treatment for some movement disorders, is now being used experimentally to treat psychiatric disorders as well. In a number of recently published case series, DBS yielded an impressive therapeutic benefit in patients with medically intractable psychiatric diseases.

METHODS

This review of the use of DBS to treat psychiatric disorders is based on literature retrieved from a selective Pubmed search for relevant keywords, reference works on the topic, and the authors' own research.

RESULTS

Studies have been performed on the use of DBS to treat medically intractable obsessive-compulsive disorder, depressive disorders, and Tourette syndrome. The case numbers in the cited publications were small, yet at least some of them involved a methodologically sound investigation. Thus, in some studies, the strength of the effect was controlled with a double-blinded interval in which the stimulation was turned off. In general, the primary symptoms were found to improve markedly, by 35% to 70%, although not all patients responded to the treatment. Adverse effects of DBS were very rare in most studies and could usually be reversed by changing the stimulation parameters.

CONCLUSIONS

The results of DBS for psychiatric disorders that have been published to date are encouraging. They open up a new perspective in the treatment of otherwise intractable disorders. Nonetheless, the efficacy, mechanism of action, and adverse effects of DBS for this indication still need to be further studied in methodologically adequate trials that meet the highest ethical standard.

Deep-brain stimulation of the nucleus accumbens in obsessive compulsive disorder: clinical, surgical and electrophysiological considerations in two consecutive patients

Obsessive compulsive disorder is a highly disabling pathological condition which in the most severe and drug-resistant form can severely impair social, cognitive and interpersonal functioning. Deep-brain stimulation has been demonstrated to be an effective and safe interventional procedure in such refractory forms in selected cases. We here report the first Italian experience in the treatment of this pathology by means of nucleus accumbens stimulation, pointing out to some technical data which could be of help in localization of the target.

Long-term outcome following Intensive Residential Treatment of Obsessive-Compulsive Disorder

BACKGROUND

IRT has been demonstrated as an effective treatment for severe, refractory OCD.

METHODS

Consecutive IRT subjects were ascertained over a 12 month period (female N=26, male N=35). Psychometric measures were completed at admission and discharge from the McLean/MGH OCD Institute IRT, including the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Beck Depression Inventory (BDI) and the Work and Social Adjustment Scale (WSA)(N=61). These measures were repeated at one (N=57), three (N=42) and six months (N=36) following discharge. This study was IRB approved.

RESULTS

OCD mean severity did not significantly worsen from discharge to the one (17.4, SD 6.5), three (16.5, SD 7.4) or six month (16.2, SD 7.3) follow-up (p>0.25). Furthermore, the significant improvement from admission was maintained at each of the one (17.4, SD 6.5), three (16.5, SD 7.4) and six month (16.2, SD SD 7.3) follow-up time points (p<0.001). Relapsers were significantly more likely to be living alone following discharge (p=0.01), and were less likely to have comorbid illnesses (p=0.02). There were no significant differences found between study dropouts and completers with regards to YBOCS scores (P>0.47).

CONCLUSION

In the first OCD IRT long-term follow-up study to date, findings have indicated that mean treatment gains were maintained at one, three, and six months post-discharge. This finding is important as it suggests that improvements of OCD severity were subsequently retained in home and work environments. Improvement of depression severity from admission was also maintained.

Three-dimensional microsurgical and tractographic anatomy of the white matter of the human brain

OBJECTIVE

We sought to investigate the three-dimensional structure of the white matter of the brain by means of the fiber-dissection technique and diffusion-tensor magnetic resonance imaging to assess the usefulness of the combination of both techniques, compare their results, and review the potential functional role of fiber tracts.

METHODS

Fifteen formalin-fixed human hemispheres were dissected according to Klingler's fiber-dissection technique with the aid of 36 to 340 magnification. Three-dimensional anatomic images were created with the use of specific software. Two hundred patients with neurological symptoms and five healthy volunteers were studied with diffusion-tensor magnetic resonance imaging (3 T) and tractographic reconstruction.

RESULTS

The most important association, projection, and commissural fasciculi were identified anatomically and radiologically. Analysis of their localization, configuration, and trajectory was enhanced by the combination of both techniques. Three-dimensional anatomic reconstructions provided a better perception of the spatial relationships among the white matter tracts. Tractographic reconstructions allowed for inspection of the relationships between the tracts as well as between the tracts and the intracerebral lesions. The combination of topographical anatomic studies of human fiber tracts and neuroanatomic research in experimental animals, with data from the clinicoradiological analysis of human white matter lesions and intraoperative subcortical stimulation, aided in establishing the potential functional role of the tracts.

CONCLUSION

The fiber-dissection and diffusion-tensor magnetic resonance imaging techniques are reciprocally enriched not only in their application to the study of the complex intrinsic architecture of the brain, but also in their practical use for diagnosis and surgical planning.

Potential surgical targets for deep brain stimulation in treatment-resistant depression

OBJECT

The goal of this study was to evaluate the definition of treatment-resistant depression (TRD), review the literature regarding deep brain stimulation (DBS) for TRD, and identify potential anatomical and functional targets for future widespread clinical application.

METHODS

A comprehensive literature review was performed to determine the current status of DBS for TRD, with an emphasis on the scientific support for various implantation sites.

RESULTS

The definition of TRD is presented, as is its management scheme. The rationale behind using DBS for depression is reviewed. Five potential targets have been identified in the literature: ventral striatum/nucleus accumbens, subgenual cingulate cortex (area 25), inferior thalamic peduncle, rostral cingulate cortex (area 24a), and lateral habenula. Deep brain stimulation electrodes thus far have been implanted and activated in only the first 3 of these structures in humans. These targets have proven to be safe and effective, albeit in a small number of cases.

CONCLUSIONS

Surgical intervention for TRD in the form of DBS is emerging as a viable treatment alternative to existing modalities. Although the studies reported thus far have small sample sizes, the results appear to be promising. Various surgical targets, such as the subgenual cingulate cortex, inferior thalamic peduncle, and nucleus accumbens, have been shown to be safe and to lead to beneficial effects with various stimulation parameters. Further studies with larger patient groups are required to adequately assess the safety and efficacy of these targets, as well as the optimal stimulation parameters and long-term effects.

Deep brain stimulation for treatment-refractory obsessive-compulsive disorder: the search for a valid target

Obsessive-compulsive disorder (OCD) is a common psychiatric disease that is marked by recurring, anxiety-provoking thoughts (obsessions) accompanied by repetitive and time-consuming behaviors (compulsions). Among the controversies in the OCD literature is the issue of the origin of the disease and whether brain changes observed with modern imaging techniques are the causes or results of OCD behaviors and thoughts. These issues remain unresolved; however, significant strides have been made in understanding the illness from both phenomenological and pathophysiological perspectives. The current staple of OCD management remains pharmacological in nature and often occurs in conjunction with cognitive behavioral therapy. Refractory cases, however, are occasionally referred for neurosurgical consultation, and several procedures have been examined. Success in the treatment of Parkinson's disease, the reversibility of the therapy, and a relatively safe side-effect profile have allowed deep brain stimulation (DBS) to be examined as an alternative treatment for some psychiatric conditions. Here we assess the possibility of applying DBS to the treatment of OCD. Morphological, functional metabolic, and volumetric data point to several brain regions that are important to the etiology and maintenance of OCD. Converging evidence from the genetics and neurocircuitry literature suggests that several subcortical structures play prominent roles in the disease. The functional modification of these structures could potentially provide symptom relief. Here, we review the ablative and DBS procedures for refractory OCD, and provide a research-driven hypothesis that highlights the ventromedial head of the caudate nucleus, and structures up- and downstream from it, as potential DBS targets for treatment-resistant disease. We hope that a research-driven approach, premised on converging evidence and previous experience, will lead to a safe and effective DBS procedure that will benefit patients who remain disabled despite presently available therapies.

Studies of caloric vestibular stimulation: implications for the cognitive neurosciences, the clinical neurosciences and neurophilosophy

OBJECTIVE

Caloric vestibular stimulation (CVS) has traditionally been used as a tool for neurological diagnosis. More recently, however, it has been applied to a range of phenomena within the cognitive neurosciences. Here, we provide an overview of such studies and review our work using CVS to investigate the neural mechanisms of a visual phenomenon - binocular rivalry. We outline the interhemispheric switch model of rivalry supported by this work and its extension to a metarivalry model of interocular-grouping phenomena. In addition, studies showing a slow rate of binocular rivalry in bipolar disorder are discussed, and the relationship between this finding and the interhemispheric switch model is described. We also review the effects of CVS in various clinical contexts, explain how the technique is performed and discuss methodological issues in its application.

METHODS

A review of CVS and related literature was conducted.

RESULTS

Despite CVS being employed with surprising effect in a wide variety of cognitive and clinical contexts, it has been a largely underutilized brain stimulation method for both exploratory and therapeutic purposes. This is particularly so given that it is well tolerated, safe, inexpensive and easy to administer.

CONCLUSION

CVS can be used to investigate various cognitive phenomena including perceptual rivalry, attention and mood, as well as somatosensory representation, belief, hemispheric laterality and pain. The technique can also be used to investigate clinical conditions related to these phenomena and may indeed have therapeutic utility, especially with respect to postlesional disorders, mania, depression and chronic pain states. Furthermore, we propose that based on existing reports of the phenomenological effects of CVS and the brain regions it is known to activate, the technique could be used to investigate and potentially treat a range of other clinical disorders. Finally, the effects of CVS (and its potential effects) on several phenomena of interest to philosophy suggest that it is also likely to become a useful tool in experimental neurophilosophy.