The effects of major depression disorder on neurogenic thoracic outlet syndrome surgery outcomes.

OBJECTIVES: Thoracic outlet syndrome (TOS) is a group of disorders caused by impingement of the neurovascular structures at the thoracic outlet. Neurogenic TOS (nTOS), which is thought to be caused by a compression of the brachial plexus, accounts for more than 90% of the cases. Although treatment for nTOS is successful through physiotherapy and/or surgical decompression, little is known about the impact of psychosocial factors, namely, major depressive disorder (MDD), on postoperative outcomes such as non-routine discharge (NRD). Here, we assess whether MDD predicts the type of discharge following nTOS surgical intervention. METHODS: A retrospective analysis of the National Inpatient Sample database from the years 2005-2018 was performed. Using the International Classification of Diseases Clinical Modification, Ninth and Tenth revisions, patients who underwent a surgical intervention for nTOS were identified. Our primary outcome was to investigate the effects of MDD on nTOS patient disposition status after surgical management; secondary outcomes included analysis of total hospital charges and length of stay. NRD was defined as anything beyond discharge home without healthcare services. Univariate and multivariable logistic regression analyses were conducted to assess MDD and other potential independent predictors of NRD and prolonged hospital stay (> 2 days) following surgical intervention. RESULTS: A total of 6099 patients were identified: 596 (9.77%) patients with MDD and 5503 (90.23%) without MDD. On average, patients with MDD were older (39.6 ± 12.0 years vs. 36.0 ± 13.0 years; p < 0.001), female (80.7% vs. 63.5%; p < 0.001), white (89.6% vs. 85.6%; p = 0.030), and on Medicare (9.6% vs 5.2%; p < 0.001). Univariate and multivariable logistic regression models identified MDD as an independent risk factor associated with a higher risk of NRD (adjusted odds ratio [aOR], 1.50; 95% confidence interval [CI], 1.0-2.2). Additionally, chronic kidney disease (aOR, 2.60; 95% CI, 1.2-5.4), postoperative complications (aOR, 1.87; 95% CI, 1.2-2.9), and Medicare (aOR, 2.95; 95% CI, 1.9-4.7) were statistically significant predictors for higher risk of NRD. However, MDD was not associated with prolonged hospital stay (aOR, 1.00; 95% CI, 0.8-1.2) or higher median of total charges (MDD group: $27,867 vs. non-MDD group: $28,123; p = 0.799). CONCLUSION: Comorbid MDD was strongly associated with higher NRD rates following nTOS surgical intervention. MDD had no significant impact on length of hospital stay or total hospital charges. Additional prospective research is necessary in order to better evaluate the impact of MDD in patients with nTOS.

Pre-existing Mental Health Diagnoses Are Associated With Higher Rates of Postoperative Complications, Readmissions, and Reoperations Following Arthroscopic Rotator Cuff Repair.

PURPOSE: To investigate the association between preoperative mental health disorders and postoperative complications, readmissions, and ipsilateral revision procedures among patients undergoing arthroscopic rotator cuff repair (RCR). METHODS: A retrospective cohort study from 2010 to 2020 was performed using the PearlDiver database. Current Procedural Terminology and International Classification of Diseases codes were used to compare patients with and without mental health disorders who underwent arthroscopic RCR. Mental health disorders evaluated in this study include depressive disorder, major depressive disorder, major depressive affective disorder, bipolar disorder, dysthymic disorder, adjustment disorder, separation anxiety disorder, and posttraumatic stress disorder. Patients were matched at a 1:1 ratio based on age, sex, Charlson Comorbidity Index, body mass index, and tobacco use. Rates of complications and subsequent surgeries were compared between patients with and without a preoperative diagnosis of a mental health disorder. RESULTS: The 1-year preoperative prevalence of a mental health disorder from 2010 to 2020 was 14.6%. After 1:1 matching, patients with a mental health disorder who underwent arthroscopic RCR were nearly twice as likely to undergo a revision procedure (odds ratio 1.94, 95% confidence interval 1.76-2.14, P < .001) and more than twice as likely to experience conversion to shoulder arthroplasty (odds ratio 2.29, 95% confidence interval 1.88-2.80, P < .001) within 2 years of initial arthroscopy when compared with patients without a mental disorder. Patients with a mental disorder also experienced increased risk for 90-day readmission (1.9% vs 0%, P < .001) as well as multiple postoperative medical complications. CONCLUSIONS: Patients with pre-existing mental health diagnoses experience increased rates of 90-day postoperative complications and readmissions following arthroscopic RCR. In addition, patients with mental health diagnoses are more likely to undergo revision repair and conversion to shoulder arthroplasty within 2 years of the index procedure. LEVEL OF EVIDENCE: Level III.

Noninvasive Capsulotomy for Refractory Depression by Frameless Stereotactic Radiosurgery.

PURPOSE: Effective treatment options for refractory depression are needed. Recent advancements permit both precise ablative radiation and functional neurologic connectome analysis using standard magnetic resonance imaging. We combined these innovations to perform stereotactic radiosurgical capsulotomy for the treatment of medically refractory major depressive disorder and study connectome response using a novel tractography-based approach. METHODS AND MATERIALS: Patients with medically refractory depression were enrolled on a prospective pilot single-arm observational trial from 2020 to 2021 at a single academic tertiary referral center. Bilateral ablation of the anterior limb of the internal capsule was accomplished by mask-based linear accelerator stereotactic radiosurgery. Beck's Depression Inventory measured efficacy. Montreal Cognitive Assessment evaluated cognition. RESULTS: Three patients were enrolled. Depression burden was improved by 88% at 12-month follow-up and by 55% at 18-month follow-up for patient 1 and 2, respectively. Patient 1 discontinued ketamine therapy, and patient 2 discontinued electroconvulsive therapy. Patient 3 reported global improvement in symptoms and function at 3 months. All 3 patients had reduction or resolution of suicidal ideation. No patient experienced cognitive decline or neurologic toxicity, and Montreal Cognitive Assessment score, as well as subjective patient-reported evaluations of concentration and attention, were superior after treatment. Tractography confirmed intended disruption of the cortico-striatal-thalamo-cortical loop with structural reorganization in the connectome. Connectome change was consistent between patients. Observed increases in caudate and putamen connectivity and decreases in thalamic connectivity may explain improved concentration, attention, and depression. The diversity and magnitude of connectome change may correlate with degree of clinical response. CONCLUSIONS: In 3 patients with refractory depression, radiosurgical capsulotomy significantly reduced the burden of depression. Functional connectome reorganization offers neurobiological evidence to support further investigations of the role of radiosurgery in depression.

Tractography-Guided Anterior Capsulotomy for Major Depression and Obsessive-Compulsive Disorder: Targeting the Emotion Network.

BACKGROUND: Bilateral anterior capsulotomy (BAC) is an effective surgical option for patients with treatment-resistant major depression (TRMD) and treatment-resistant obsessive-compulsive disorder (TROCD). The size of the lesion and its precise dorsal-ventral location within the anterior limb of the internal capsule (ALIC) remain undefined. OBJECTIVE: To present a method to identify the trajectories of the associative and limbic white matter pathways within the ALIC for targeting in BAC surgery. METHODS: Using high-definition tractography, we prospectively tested the feasibility of this method in 2 patients with TRMD and TROCD to tailor the capsulotomy lesion to their limbic pathway. RESULTS: The trajectories of the associative and limbic pathways were identified in the ALIC of both patients and we targeted the limbic pathways by defining the dorsal limit of the lesion in a way to minimize the damage to the associative pathways. The final lesions were smaller than those that have been previously published. This individualized procedure was associated with long-term benefit in both patients. CONCLUSION: Tractography-guided capsulotomy is feasible and was associated with long-term benefit in patients with TRMD and TROCD.

Deep brain stimulation telemedicine programming during the COVID-19 pandemic: treatment of patients with psychiatric disorders.

OBJECTIVE: The ongoing coronavirus disease 2019 (COVID-19) pandemic has considerably affected the delivery of postoperative care to patients who have undergone deep brain stimulation (DBS) surgery. DBS teleprogramming technology was developed and deployed in China before the COVID-19 outbreak. In this report, the authors share their experiences with telemedical DBS treatment of patients with psychiatric disorders during the COVID-19 outbreak. METHODS: Four patients (2 with obsessive-compulsive disorder, 1 with major depressive disorder, and 1 with anorexia nervosa) underwent DBS surgery at Ruijin Hospital and received continuous postoperative DBS telemedicine case management from January 2020 to July 2020. DBS teleprogramming, individualized psychological support, and medical consultations were provided via the authors' DBS telemedicine platform, which also incorporated a synchronous real-time video communication system. RESULTS: Forty-five DBS telemedicine sessions were conducted; there was no unexpected loss of network connection during the sessions. Of these, 28 sessions involved DBS teleprogramming. Adjustments were made to the stimulation voltage, frequency, pulse width, and contact site in 21, 12, 9, and 9 sessions, respectively. Psychological support and troubleshooting were provided during the remaining telemedicine sessions. Modest to substantial clinical improvements after DBS surgery were observed in some but not all patients, whereas stimulation-related side effects were reported by 2 patients and included reversible sleep and mood problems, headache, and a sensation of heat. CONCLUSIONS: DBS telemedicine seems to offer a feasible, safe, and efficient strategy for maintaining the delivery of medical care to psychiatric patients during the COVID-19 outbreak. The authors propose that implementation of a comprehensive DBS telemedicine system, which combines DBS teleprogramming with psychological counseling, medical consultations, and medication prescriptions and delivery, could be an efficient and effective approach to manage the mental health and quality of life of patients with psychiatric disorders during future local or global public health crises.

Effect of Comorbid Depression on Surgical Outcomes After Craniotomy for Malignant Brain Tumors: A Nationwide Readmission Database Analysis.

OBJECTIVE: Quality of life is paramount in patients with advanced cancer and may be adversely affected by comorbid depression. We hypothesized that comorbid depression is associated with higher rates of postoperative complications, worse functional outcomes, and higher rates of readmission after craniotomy for resection of malignant intracranial tumors. METHODS: The National Readmissions Database was queried from 2010 to 2014 to identify adult patients undergoing craniotomy for malignant brain tumor resection. The primary psychiatric disease assessed was major depressive disorder (MDD). Outcomes evaluated included neurologic or other major complications, incidence of nonroutine discharge, and unplanned readmission at 30 and 90 days. RESULTS: Of the 57,621 craniotomies for malignant neoplasms included in the analysis, 11.32% of patients had clinically diagnosed MDD. The presence of MDD was associated with nonroutine discharge (odds ratio, 1.10-125; P < 0.0001) as well as higher rates of neurologic complications (odds ratio, 1.03-1.18; P = 0.003). No association between MDD and 30-day or 90-day readmissions was noted. Patients with major All Patient Refined Diagnosis Related Groups severity and index length of stay >7 days experienced higher rates of 30-day and 90-day readmissions. CONCLUSIONS: There is a clinically significant rate of comorbid MDD in patients with malignant intracranial tumors, and MDD is associated with worse perioperative outcomes. Given the wealth of behavioral and pharmaceutical therapies available, MDD is a modifiable risk factor in this cohort that clinicians should be vigilant in screening for and initiating appropriate treatment protocols.

An Analysis of Clinical Outcome and Tractography following Bilateral Anterior Capsulotomy for Depression.

INTRODUCTION: Bilateral anterior capsulotomy (BAC) is an effective surgical procedure for patients with treatment-resistant major depression (TRMD). In this work, we analyze the connectivity of the BAC lesions to identify connectivity "fingerprints" associated with clinical outcomes in patients with TRMD. METHODS: We performed a retrospective study of ten patients following BAC surgery. These patients were divided into "responders" and "non-responders" based on the relative change in the Beck depression inventory (BDI) score after surgery. We generated the dorsolateral prefrontal associative (DLPFC) pathways and the ventromedial prefrontal limbic (vmPFC) pathways going through the anterior limb of the internal capsule and analyzed if the overlap of the BAC lesions with these pathways was associated with either outcome. Finally, we used the BAC lesions of our patients to generate group-averaged connectivity "fingerprints" associated with either outcome. RESULTS: Six patients were responders (≥50% improvement in BDI), four patients were non-responders (<50% improvement). No significant impairments were found in most neuropsychological tests after surgery. The overlap analysis showed that in the responder group, there was less involvement of the DLPFC pathways than the vmPFC pathways (p = 0.001). Conversely, in the non-responder group, there was no significant difference between the involvement of both pathways (p = 0.157). The responder and non-responder connectivity fingerprint showed significant connections with the vmPFC limbic areas. However, the non-responder connectivity fingerprint also showed stronger connectivity to associative areas including the DLPFC and lateral orbitofrontal cortices. CONCLUSIONS: The optimum outcome following BAC surgery in this cohort was associated with interruption of vmPFC pathways and the relative preservation of DLPFC pathways.

Tractography-assisted deep brain stimulation of the superolateral branch of the medial forebrain bundle (slMFB DBS) in major depression.

Background: Deep brain stimulation (DBS) of the superolateral branch of the medial forebrain bundle (slMFB) emerges as a - yet experimental - treatment for major depressive disorder (MDD) and other treatment refractory psychiatric diseases. First experiences have been reported from two open label pilot trials in major depression (MDD) and long-term effectiveness for MDD (50 months) has been reported. Objective: To give a detailed description of the surgical technique for DBS of the superolateral branch of the medial forebrain bundle (slMFB) in MDD. Methods: Surgical experience from bilateral implantation procedures in n = 24 patients with MDD is reported. The detailed procedure of tractography-assisted targeting together with detailed electrophysiology in 144 trajectories in the target region (recording and stimulation) is described. Achieved electrode positions were evaluated based on postoperative helical CT and fused to preoperative high resolution anatomical magnetic resonance imaging (MRI; Philips Medical Systems, Best, Netherlands), including the pre-operative diffusion tensor imaging (DTI) tractographic information (StealthViz DTI, Medtronic, USA; Framelink 5.0, Medtronic, USA). Midcommissural point (MCP) coordinates of effective contact (EC) location, together with angles of entry into the target region were evaluated. To investigate incidental stimulation of surrounding nuclei (subthalamic nucleus, STN; substantia nigra, SNr; and red nucleus, RN) as a possible mechanism, a therapeutic triangle (TT) was defined, located between these structures (based on MRI criteria in T2) and evaluated with respect to EC locations. Results: Bilateral slMFB DBS was performed in all patients. We identified an electrophysiological environment (defined by autonomic reaction, passive microelectrode recording, acute effects and oculomotor effects) that helps to identify the proper target site on the operation table. Postoperative MCP-evaluation of effective contacts (EC) shows a significant variability with respect to localization. Evaluation of the TT shows that responders will typically have their active contacts inside the triangle and that surrounding nuclei (STN, SNr, RN) are not directly hit by EC, indicating a predominant white matter stimulation. The individual EC position within the triangle cannot be predicted and is based on individual slMFB (tractography) geometry. There was one intracranial bleeding (FORESEE I study) during a first implantation attempt in a patient who later received full bilateral implantation. Typical oculomotor side effects are idiosyncratic for the target region and at inferior contacts. Conclusion: The detailed surgical procedure of slMFB DBS implantation has not been described before. The slMFB emerges as an interesting region for the treatment of major depression (and other psychiatric diseases) with DBS. So far it has only been successfully researched in open label clinical case series and in 15 patients published. Stimulation probably achieves its effect through direct white-matter modulation of slMFB fibers. The surgical implantation comprises a standardized protocol combining tractographic imaging based on DTI, targeting and electrophysiological evaluation of the target region. To this end, slMFB DBS surgery is in technical aspects comparable to typical movement disorder surgery. In our view, slMFB DBS should only be performed under tractographic assistance.

The History and Future of Ablative Neurosurgery for Major Depressive Disorder.

BACKGROUND: There is an urgent need to develop safe and effective treatments for patients with treatment-resistant depression (TRD). Several neurosurgical procedures have been developed to treat the dysfunctional brain circuits implicated in major depression. OBJECTIVES: This review describes the most common ablative procedures used to treat major depressive disorder: anterior cingulotomy, subcaudate tractotomy, limbic leucotomy, and anterior capsulotomy. The efficacy and safety of each are discussed and compared with other current and emerging modalities, including deep brain stimulation (DBS) and MR-guided focused ultrasound (MRgFUS). METHODS: The PubMed and MEDLINE electronic databases were used in this study, through July 2016. Keywords, including "treatment resistant depression," and "ablative neurosurgery," etc. were used to generate reference hits. RESULTS: Approximately a third to half of patients who underwent ablative procedures achieved a treatment response and/or remission. The efficacy and safety profiles corresponding to both ablative procedures and DBS were very similar. CONCLUSIONS: The longitudinal experience with ablative procedures shows that there remains an important role for accurate, discrete lesions in disrupting affective circuitry in the treatment of TRD. New modalities, such as MRgFUS, have the potential to further improve the accuracy of ablative procedures, while enhancing safety by obviating the need for open brain surgery.

Surgery for psychiatric disorders.

Surgery in psychiatric disorders has a long history and has regained momentum in the past few decades with deep brain stimulation (DBS). DBS is an adjustable and reversible neurosurgical intervention using implanted electrodes to deliver controlled electrical pulses to targeted areas of the brain. It holds great promise for therapy-refractory obsessive-compulsive disorder. Several double-blind controlled and open trials have been conducted and the response rate is estimated around 54%. Open trials have shown encouraging results with DBS for therapy-refractory depression and case reports have shown potential effects of DBS on addiction. Another promising indication is Tourette syndrome, where potential efficacy of DBS is shown by several case series and a few controlled trials. Further research should focus on optimizing DBS with respect to target location and increasing the number of controlled double-blinded trials. In addition, new indications for DBS and new target options should be explored in preclinical research.

Unilateral right anterior capsulotomy for refractory major depression with comorbid obsessive-compulsive disorder.

BACKGROUND: Treatment-resistant major depression (MDD) and obsessive-compulsive disorder (OCD) remain a major cause of suffering and disability. These disorders may be treated with functional neurosurgery that almost always is bilateral but some patients might benefit from unilateral procedures. METHODS: We performed a unilateral right anterior capsulotomy (AC) in a 45-year-old right-handed woman with MDD and comorbid OCD. This unilateral procedure was based on the results of neuropsychological testing and an 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) that revealed right hemisphere deficits in this patient. RESULTS: Following surgery, Hamilton Depression scale (HAM-D) decreased 57% at 1 and 2 years and 54% at 3 years and Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) decreased 58% at 1 year, 77% at 2 years, and 96% at 3 years. There was a slight decrement of verbal memory and phonemic fluency after the procedure that could also be related to changes in medication. Right basal ganglia abnormalities revealed by FDG-PET remained unchanged 16 months postoperatively. CONCLUSIONS: Overall this unilateral right AC was effective for the treatment of this woman's disorders with minimal adverse side effects.

Antipsychotic medication is associated with selective alterations in ventricular cerebrospinal fluid Aß 40 and tau in patients with intractable unipolar depression.

OBJECTIVE: Alterations in plasma and in lumbar cerebrospinal fluid amyloid-B peptide (Aß) levels have been reported in Alzheimer's disease. Studies have also suggested similar changes in depressed patients. No information is available on the impact of psychotropic drugs on this in patients with depression. We therefore quantified Aß in ventricular cerebrospinal fluid (CSF) in a population of patients with treatment-resistant depression, with and without antipsychotic medication. METHOD: A cross-sectional study of 32 patients undergoing subcaudate tractotomy for major (unipolar) depressive disorder. Ventricular CSF concentrations of Aß peptide 1-40 and 1-42, also p-tau and total tau were determined by Western blotting or enzyme-linked immunosorbent assay. RESULTS: Patients taking antipsychotic medication in the 2 weeks prior to surgery demonstrated significantly higher levels of Aß 1-40 (mean ± SD: 727.3 ± 382.3 vs. 440.9 ± 337.2 pg/ml; p = 0.032, Student's t-test) but unaltered Aß 1-42 (mean 72.1 ± 67.5 vs. 60.0 ± 56.7 pg/ml; p = 0.587) compared to a matched sample not treated with antipsychotic drugs. The same group demonstrated elevated total tau (mean 945.0 ± 422.2 vs. 534.3 ± 388.3 pg/ml; p = 0.010) but not p-tau (mean 98.6 ± 71.5 vs. 88.1 ± 70.5 pg/ml; p = 0.694). No similar effect was found with lithium, antidepressants, carbamazepine or benzodiazepines. CONCLUSIONS: This preliminary study suggests antipsychotic drugs, widely used in patients with severe depression across all age ranges, may be associated with alteration of Aß 1-40 and total tau, indices strongly linked with progressive organic brain disease. Further confirmatory work is needed.

Physiological responses to brain stimulation during limbic surgery: further evidence of anterior cingulate modulation of autonomic arousal.

BACKGROUND: In view of conflicting neuroimaging results regarding autonomic-specific activity within the anterior cingulate cortex (ACC), we investigated autonomic responses to direct brain stimulation during stereotactic limbic surgery. METHODS: Skin conductance activity and accelerative heart rate responses to multi-voltage stimulation of the ACC (n = 7) and paralimbic subcaudate (n = 5) regions were recorded during bilateral anterior cingulotomy and bilateral subcaudate tractotomy (in patients that had previously received an adequate lesion in the ACC), respectively. RESULTS: Stimulations in both groups were accompanied by increased autonomic arousal. Skin conductance activity was significantly increased during ACC stimulations compared with paralimbic targets at 2 V (2.34 +/- .68 [score in microSiemens +/- SE] vs. .34 +/- .09, p = .013) and 3 V (3.52 +/- .86 vs. 1.12 +/- .37, p = .036), exhibiting a strong "voltage-response" relationship between stimulus magnitude and response amplitude (difference from 1 to 3 V = 1.15 +/- .90 vs. 3.52 +/- .86, p = .041). Heart rate response was less indicative of between-group differences. CONCLUSIONS: This is the first study of its kind aiming at seeking novel insights into the mechanisms responsible for central autonomic modulation. It supports a concept that interregional interactions account for the coordination of autonomic arousal.

Subcallosal cingulate gyrus deep brain stimulation for treatment-resistant depression.

BACKGROUND: A preliminary report in six patients suggested that deep brain stimulation (DBS) of the subcallosal cingulate gyrus (SCG) may provide benefit in treatment-resistant depression (TRD). We now report the results of these and an additional 14 patients with extended follow-up. METHODS: Twenty patients with TRD underwent serial assessments before and after SCG DBS. We determined the percentage of patients who achieved a response (50% or greater reduction in the 17-item Hamilton Rating Scale for Depression [HRSD-17]) or remission (scores of 7 or less) after surgery. We also examined changes in brain metabolism associated with DBS, using positron emission tomography. RESULTS: There were both early and progressive benefits to DBS. One month after surgery, 35% of patients met criteria for response with 10% of patients in remission. Six months after surgery, 60% of patients were responders and 35% met criteria for remission, benefits that were largely maintained at 12 months. Deep brain stimulation therapy was associated with specific changes in the metabolic activity localized to cortical and limbic circuits implicated in the pathogenesis of depression. The number of serious adverse effects was small with no patient experiencing permanent deficits. CONCLUSIONS: This study suggests that DBS is relatively safe and provides significant improvement in patients with TRD. Subcallosal cingulate gyrus DBS likely acts by modulating brain networks whose dysfunction leads to depression. The procedure is well tolerated and benefits are sustained for at least 1 year. A careful double-blind appraisal is required before the procedure can be recommended for use on a wider scale.

Prospective assessment of stereotactic ablative surgery for intractable major depression.

BACKGROUND: Despite therapeutic advances for major depression, a subset of patients with this disorder does not respond to conventional treatment. Stereotactic ablative procedures such as anterior cingulotomy have been performed in severely affected, treatment-resistant patients, but the long-term results of such procedures are not fully understood. METHODS: Findings are reported for 33 patients with severe treatment-resistant major depression who underwent ablative stereotactic procedures (dorsal anterior cingulotomy followed if necessary by subcaudate tractotomy). Preoperative and long-term postoperative Beck Depression Inventory scores were obtained along with postoperative Clinical Global Improvement values. Both were analyzed to evaluate patients' responses to the surgical procedure(s). RESULTS: At mean follow-up of 30 months after one or more stereotactic ablative procedures, 11 patients (33.3%) were classified as responders, 14 (42.4%) were partial responders, and 8 (24.2%) did not respond to the surgical procedure(s). Among those (17) who underwent only one procedure, seven (41.2%) responded, whereas six (35.3%) and four (23.5%) showed partial or no response, respectively. Among patients who required multiple surgical procedures, four patients (25%) responded, whereas eight (50%) and four (25%) patients demonstrated partial or no responses, respectively, at long-term follow-up evaluations. CONCLUSIONS: Approximately 75% of depression patients previously resistant to antidepressant therapies received partial or substantial benefit from stereotactic ablative procedures. Those requiring only a single anterior cingulotomy tended to demonstrate more pronounced responses than patients who underwent multiple surgical procedures.

Anterior cingulotomy for major depression: clinical outcome and relationship to lesion characteristics.

BACKGROUND: Anterior cingulotomy (ACING) is a neurosurgical treatment for chronic refractory depression, pain, and obsessive-compulsive disorder. Anterior cingulotomy involves the placement of bilateral lesions in the anterior cingulate under stereotactic guidance. Although a long-established therapeutic intervention, the optimal location and volume of lesions are not known, but it is generally believed that efficacious lesions interrupt the fibers of the cingulum bundle. METHODS: Using T2-weighted magnetic resonance imaging, we tested the hypothesis that lesions placed more anteriorly would be associated with a better clinical response. We also tested a secondary hypothesis that a superior clinical response would be associated with larger lesion volumes. RESULTS: When assessed 12 months following surgery, a superior clinical response was associated with more anterior lesions but, unexpectedly, with smaller lesion volumes. Specifically, the best clinical response was associated with total (right plus left hemisphere) lesion volumes of 1000 to 2000 mm(3) centered at Montreal Neurological Institute (MNI) coordinates (+/- 9,19,30). CONCLUSIONS: There is considerable evidence from neuroimaging studies that more rostral areas within the anterior cingulate cortex are functionally and structurally abnormal in patients with major depressive disorder. Anteriorly placed ACING lesions would target and modify function within such regions. It should not be assumed that larger lesions are associated with a better response. These findings of relationships between lesion characteristics and clinical response argue against the suggestion that ACING represents a placebo treatment.

Is deep brain stimulation a form of psychosurgery?

OBJECTIVE: To examine the potential for the experimental treatment of deep brain stimulation for neuropsychiatric disorders, and to debate the argument that it should be considered another form of psychosurgery. CONCLUSIONS: Psychosurgery is an old term with considerable pejorative connotations. It should be replaced with the more descriptive and accurate 'neurosurgery for psychiatric disorders'. Moreover, neurosurgery should reflect ablative neurosurgery, and surgery for brain stimulation should be categorised as brain stimulation rather than neurosurgery, or indeed psychosurgery. This will prevent legislative restrictions on the development of brain stimulation techniques and not tar them with the lobotomy brush.

Long-term habituation of the smile response with deep brain stimulation.

Human and animal research has shown that the ventral striatum, including the nucleus accumbens, may play a critical role in mediating positive emotions. Recently we described a subject with obsessive-compulsive disorder who intra-operatively exhibited the acute onset of an asymmetric smile and acute positive emotional change with contralateral deep brain stimulation (DBS) in either the right or left nucleus accumbens and anterior limb of the internal capsule region. The purpose of the present study was to examine the stability of the stimulation-induced smile(s) over a 12-month period. Custom computer software objectively quantified left and right facial movement during DBS. Although stimulation-induced smiles were elicited at one and two months post-surgery, they were no longer present from 3-12 months following chronic high frequency DBS. The smiles could not be elicited even with long washout periods. These findings imply potential long-term habituation and changes in the neural chemistry (possibly neuroplasticity) induced by chronic DBS.