Stereotactic limbic leucotomy: a preliminary report on forty patients

Role of deep brain stimulation in management of psychiatric disorders

Nowadays, most of patients affected by psychiatric disorders are successfully treated with conservative therapies. Still, a variable percentage of them demonstrate resistance to conventional treatments, and alternative methods can then be considered. During the last 20 years, there is a progressive interest in use of deep brain stimulation (DBS) in mental illnesses. It has become clear nowadays, that this modality may be effectively applied under specific indications in some patients with major depressive disorder, obsessive-compulsive disorder, anorexia nervosa and other eating disorders, Tourette syndrome, schizophrenia, substance use disorder, and even pathologically aggressive behavior. Despite the fact that the efficacy of neuromodulation with DBS, as well as of various lesional interventions, in cases of mental illnesses is still not fully established, there are several premises for wider applications of such "unclassical" psychiatric treatments in the future. Novel technologies of DBS, developments in non-invasive lesioning using stereotactic radiosurgery and transcranial magnetic resonance-guided focused ultrasound, and advances of neurophysiological and neuroimaging modalities may bolster further clinical applications of psychiatric neurosurgery, improve its results, and allow for individually selected treatment strategies tailored to specific needs of the patient.

The prefrontal cortex and neurosurgical treatment for intractable OCD

Over the past two decades, circuit-based neurosurgical procedures have gained increasing acceptance as a safe and efficacious approach to the treatment of the intractable obsessive-compulsive disorder (OCD). Lesions and deep brain stimulation (DBS) of the longitudinal corticofugal white matter tracts connecting the prefrontal cortex with the striatum, thalamus, subthalamic nucleus (STN), and brainstem implicate orbitofrontal, medial prefrontal, frontopolar, and ventrolateral cortical networks in the symptoms underlying OCD. The highly parallel distributed nature of these networks may explain the relative lack of adverse effects observed following surgery. Additional pre-post studies of cognitive tasks in more surgical patients are needed to confirm the role of these networks in OCD and to define therapeutic responses to surgical intervention.

Lesion location and outcome following cingulotomy for obsessive-compulsive disorder

OBJECTIVE

Obsessive-compulsive disorder (OCD) is among the most debilitating and medically refractory psychiatric disorders. While cingulotomy is an anatomically targeted neurosurgical treatment that has shown significant promise in treating OCD-related symptoms, the precise underlying neuroanatomical basis for its beneficial effects has remained poorly understood. Therefore, the authors sought to determine whether lesion location is related to responder status following cingulotomy.

METHODS

The authors reviewed the records of 18 patients who had undergone cingulotomy. Responders were defined as patients who had at least a 35% improvement in the Yale-Brown Obsessive Compulsive Scale (YBOCS) score. The authors traced the lesion sites on T1-weighted MRI scans and used an anatomical registration matrix generated by the imaging software FreeSurfer to superimpose these lesions onto a template brain. Lesion placement was compared between responders and nonresponders. The placement of lesions relative to various anatomical regions was also compared.

RESULTS

A decrease in postoperative YBOCS score was significantly correlated with more superiorly placed lesions (decrease -0.52, p = 0.0012). While all lesions were centered within 6 mm of the cingulate sulcus, responder lesions were placed more superiorly and posteriorly along the cingulate sulcus (1-way ANOVA, p = 0.003). The proportions of the cingulum bundle, cingulate gyrus, and paracingulate cortex affected by the lesions were the same between responders and nonresponders. However, all responders had lesions covering a larger subregion of Brodmann area (BA) 32. In particular, responder lesions covered a significantly greater proportion of the posterior BA32 (1-way ANOVA, p = 0.0064).

CONCLUSIONS

Lesions in patients responsive to cingulotomy tended to be located more superiorly and posteriorly and share greater coverage of a posterior subregion of BA32 than lesions in patients not responsive to this treatment.

Alternatives to Pharmacological and Psychotherapeutic Treatments in Psychiatric Disorders

Nowadays, most of the patients affected by psychiatric disorders are successfully treated with psychotherapy and pharmacotherapy. Nevertheless, according to the disease, a variable percentage of patients results resistant to such modalities, and alternative methods can then be considered. The purpose of this review is to summarize the techniques and results of invasive modalities for several treatment-resistant psychiatric diseases. A literature search was performed to provide an up-to-date review of advantages, disadvantages, efficacy, and complications of Deep-Brain Stimulation, Magnetic Resonance-guided Focused-Ultrasound, radiofrequency, and radiotherapy lesioning for depression, obsessive-compulsive disorder, schizophrenia, addiction, anorexia nervosa, and Tourette’s syndrome. The literature search did not strictly follow the criteria for a systematic review: due to the large differences in methodologies and patients’ cohort, we tried to identify the highest quality of available evidence for each technique. We present the data as a comprehensive, narrative review about the role, indication, safety, and results of the contemporary instrumental techniques that opened new therapeutic fields for selected patients unresponsive to psychotherapy and pharmacotherapy.

Ablative brain surgery: an overview

Background: Ablative therapies have been used for the treatment of neurological disorders for many years. They have been used both for creating therapeutic lesions within dysfunctional brain circuits and to destroy intracranial tumors and space-occupying masses. Despite the introduction of new effective drugs and neuromodulative techniques, which became more popular and subsequently caused brain ablation techniques to fall out favor, recent technological advances have led to the resurgence of lesioning with an improved safety profile. Currently, the four main ablative techniques that are used for ablative brain surgery are radiofrequency thermoablation, stereotactic radiosurgery, laser interstitial thermal therapy and magnetic resonance-guided focused ultrasound thermal ablation. Object: To review the physical principles underlying brain ablative therapies and to describe their use for neurological disorders. Methods: The literature regarding the neurosurgical applications of brain ablative therapies has been reviewed. Results: Ablative treatments have been used for several neurological disorders, including movement disorders, psychiatric disorders, chronic pain, drug-resistant epilepsy and brain tumors. Conclusions: There are several ongoing efforts to use novel ablative therapies directed towards the brain. The recent development of techniques that allow for precise targeting, accurate delivery of thermal doses and real-time visualization of induced tissue damage during the procedure have resulted in novel techniques for cerebral ablation such as magnetic resonance-guided focused ultrasound or laser interstitial thermal therapy. However, older techniques such as radiofrequency thermal ablation or stereotactic radiosurgery still have a pivotal role in the management of a variety of neurological disorders.

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.

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.

Deep Brain Stimulation of Medial Dorsal and Ventral Anterior Nucleus of the Thalamus in OCD: A Retrospective Case Series

BACKGROUND

The current notion that cortico-striato-thalamo-cortical circuits are involved in the pathophysiology of obsessive-compulsive disorder (OCD) has instigated the search for the most suitable target for deep brain stimulation (DBS). However, despite extensive research, uncertainty about the ideal target remains with many structures being underexplored. The aim of this report is to address a new target for DBS, the medial dorsal (MD) and the ventral anterior (VA) nucleus of the thalamus, which has thus far received little attention in the treatment of OCD.

METHODS

In this retrospective trial, four patients (three female, one male) aged 31-48 years, suffering from therapy-refractory OCD underwent high-frequency DBS of the MD and VA. In two patients (de novo group) the thalamus was chosen as a primary target for DBS, whereas in two patients (rescue DBS group) lead implantation was performed in a rescue DBS attempt following unsuccessful primary stimulation.

RESULTS

Continuous thalamic stimulation yielded no significant improvement in OCD symptom severity. Over the course of thalamic DBS symptoms improved in only one patient who showed "partial response" on the Yale-Brown Obsessive Compulsive (Y-BOCS) Scale. Beck Depression Inventory scores dropped by around 46% in the de novo group; anxiety symptoms improved by up to 34%. In the de novo DBS group no effect of DBS on anxiety and mood was observable.

CONCLUSION

MD/VA-DBS yielded no adequate alleviation of therapy-refractory OCD, the overall strategy in targeting MD/VA as described in this paper can thus not be recommended in DBS for OCD. The magnocellular portion of MD (MDMC), however, might prove a promising target in the treatment of mood related and anxiety disorders.

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.

[Surgery for behavioral disorders: the state of the art]

BACKGROUND

Surgery for behavioral disorders (SBD) is becoming a more common treatment since the development of neuromodulation techniques.

METHODS

This article is a non-systematic review of the history, current indications, techniques and surgical targets of SBD. We divide its history into 3 eras: the first era starts in the beginning of psychosurgery and finishes with the development of stereotactic techniques, when the second one starts. It is characterized by the realization of stereotactic lesions. We are traveling through the third era, which begins when deep brain stimulation (DBS) starts to be used for SBD.

RESULTS

In spite of the serious mistakes committed in the past, nowadays, SBD is reawakening. The psychiatric disorders which are most frequently treated by surgery are: treatment-resistant depression, obsessive-compulsive disorder and Tourette syndrome. Furthermore, some patients with abnormal aggression were surgically treated. There are several stereotactic targets described for these disorders. Vagus nerve stimulation may be also used for depression.

CONCLUSION

The results of DBS in these disorders seem to be encouraging. However, more randomized trials are needed in order to establish the effectiveness of SBD. It must be taken in mind that a proper patient selection will help us to perform a safer procedure as well as to achieve better surgical results, leading SBD to be more accepted by psychiatrists, patients and their families. Further research is needed in several topics such as: physiopathology of behavioral disorders, indications of SBD and new surgical targets.

Deep brain stimulation for treatment-resistant depression: systematic review of clinical outcomes

Major depressive disorder (MDD) is a widespread, severe, debilitating disorder that markedly diminishes quality of life. Medication is commonly effective, but 20-30 % of patients are refractory to medical therapy. The surgical treatment of psychiatric disorders has a negative stigma associated with it owing to historical abuses. Various ablative surgeries for MDD have been attempted with marginal success, but these studies lacked standardized outcome measures. The recent development of neuromodulation therapy, especially deep brain stimulation (DBS), has enabled controlled studies with sham stimulation and presents a potential therapeutic option that is both reversible and adjustable. We performed a systematic review of the literature pertaining to DBS for treatment-resistant depression to evaluate the safety and efficacy of this procedure. We included only studies using validated outcome measures. Our review identified 22 clinical research papers with 5 unique DBS approaches using different targets, including nucleus accumbens, ventral striatum/ventral capsule, subgenual cingulate cortex, lateral habenula, inferior thalamic nucleus, and medial forebrain bundle. Among the 22 published studies, only 3 were controlled trials, and 2, as yet unpublished, multicenter, randomized, controlled trials evaluating the efficacy of subgenual cingulate cortex and ventral striatum/ventral capsule DBS were recently discontinued owing to inefficacy based on futility analyses. Overall, the published response rate to DBS therapy, defined as the percentage of patients with > 50 % improvement on the Hamilton Depression Rating Scale, is reported to be 40-70 %, and outcomes were comparable across studies. We conclude that DBS for MDD shows promise, but remains experimental and further accumulation of data is warranted.

Deep brain stimulation and ablation for obsessive compulsive disorder: evolution of contemporary indications, targets and techniques

Surgical therapy for treatment-resistant obsessive compulsive disorder (OCD) remains an effective option for well-selected patients managed within a multidisciplinary setting. Historically, lesions within the limbic system have been used to control both obsessive thoughts and repetitive compulsions associated with this disease. We discuss classical targets as well as contemporary neuromodulatory approaches that have been shown to provide symptomatic relief. Recently, deep brain stimulation (DBS) of the anterior limb of the internal capsule/ventral striatum received Conformité Européene (CE) mark and Food and Drug Administration (FDA) approvals for treatment of intractable OCD. Remarkably, this is the first such approval for neurosurgical intervention in a strictly psychiatric indication in modern times. This target is discussed in detail along with alternative targets currently being proposed. We close with a discussion of gamma knife capsulotomy, a modality with deep historical roots. Further directions in the surgical treatment of OCD will require better preoperative predictors of postoperative responses, optimal selection of individualized targets, and rigorous reporting of adverse events and standardized outcomes. To meet these challenges, centers must be equipped with a multidisciplinary team and patient-centered approach to ensure adequate screening and follow up of patients with this difficult-to-treat condition.

The anteromedial GPi as a new target for deep brain stimulation in obsessive compulsive disorder

Deep brain stimulation (DBS) is now well established in the treatment of intractable movement disorders. Over the past decade the clinical applications have expanded into the realm of psychosurgery, including depression and obsessive compulsive disorder (OCD). The optimal targets for electrode placement in psychosurgery remain unclear, with numerous anatomical targets reported for the treatment of OCD. We present four patients with Tourette's syndrome and prominent features of OCD who underwent DBS of the anteromedial globus pallidus internus (GPi) to treat their movement disorder. Their pre-operative and post-operative OCD symptoms were compared, and responded dramatically to surgery. On the basis of these results, we propose the anteromedial (limbic) GPi as a potential surgical target for the treatment of OCD, and furnish data supporting its further investigation as a DBS target for the treatment of psychiatric conditions.

Beneficial effect of subsequent lesion procedures after nonresponse to initial cingulotomy for severe, treatment-refractory obsessive-compulsive disorder

BACKGROUND

Anterior cingulotomy (AC) can be an effective therapy for patients with severe obsessive-compulsive disorder who are refractory to traditional medical therapy. For patients who do not respond to AC, the benefit of additional lesion procedures vs continued medical management remains unknown.

OBJECTIVE

To determine whether a second lesion procedure is beneficial after unsuccessful initial AC.

METHODS

In this retrospective cohort study, we reviewed the records of 31 patients who were nonresponders to initial AC. Full response was defined as at least a 35% decrease and partial response as a 25% to 34% decrease in Yale-Brown Obsessive-Compulsive Scale scores. Yale-Brown Obsessive-Compulsive Scale change was compared between patients who underwent additional surgery and those treated nonsurgically. In addition, for patients who underwent additional surgery, we compared the benefit of subcaudate tractotomy with repeat AC (extension of the initial lesion) as the second procedure.

RESULTS

Nineteen patients underwent a second surgery and 12 patients continued nonsurgical therapy. Fifty-three percent of patients who received additional surgery were full responders and 21% were partial responders at the most recent follow-up compared with 17% full responders and 25% partial responders among those who continued conventional therapy (P = .02). Of the patients who underwent an additional surgery, there were 64% full and 9% partial responders in the subcaudate tractotomy group compared with 38% full and 38% partial responders in the repeat AC group (P = .04).

CONCLUSION

Second lesion surgery can be a safe and effective therapy for patients who do not respond to initial AC. Subcaudate tractotomy may confer a higher response rate than repeat cingulotomy.

Deep brain stimulation in obsessive-compulsive disorder: neurocircuitry and clinical experience

The last decade has seen a significant rise in interest in the use of deep brain stimulation (DBS) for the management of obsessive-compulsive disorder (OCD), one of psychiatry's most challenging conditions. The prominent role of both thought (obsessions) and motor (compulsions) dysfunction in OCD place the condition at the border between the neurological and the psychiatric. This is supported by a growing body of literature that implicates structures in decision-making, reward, and action-selection circuits in the disorder. Here, we provide an overview of the neurocircuitry of OCD while reviewing the DBS literature to date for the condition. Results of DBS trials in treatment- resistant OCD have been remarkably similar, with clinical response rates in the range of 40-60%, despite the use of a diverse range of targets. These results imply that a common underlying circuit is being modulated, and moreover that there is room for improvement, and debate, in the development of an evidence-driven DBS treatment for this chronic, debilitating illness.

Neurosurgical treatments of depression

The neurosurgical treatment of treatment-resistant depression (TRD) has entered a new era with more and more patients being treated with deep brain stimulation (DBS) via surgically implanted intracerebral electrodes. Although the mechanisms of action of DBS are still not fully understood, preclinical studies are being conducted to elucidate how the treatment might work. DBS in its present form can be considered as a relatively new neurosurgical treatment for TRD. However, the use of neurosurgery in the management of depression has a much longer history particularly with ablative procedures but also vagal nerve stimulation. Here, we provide a review of the clinical neurosurgical treatments for TRD, with a main emphasis on DBS. In addition, we discuss relevant preclinical data that are revealing new information about DBS mechanisms.

Limbic system surgery for treatment-refractory obsessive-compulsive disorder: a prospective long-term follow-up of 64 patients

OBJECT

Obsessive-compulsive disorder (OCD) is a common and disabling psychiatric illness, and in a significant proportion of patients with OCD the disease is refractory to conventional pharmacotherapy and psychotherapy. For more than half a century, patients with severe, treatment-resistant OCD have been treated with stereotactic limbic system lesions, including dorsal anterior cingulotomy. The authors present their results describing the efficacy and durability of limbic system surgery for OCD, characterizing a large cohort of patients treated at a single institution with a mean follow-up of more than 5 years.

METHODS

The authors identified 64 consecutive patients undergoing cingulotomy for refractory OCD at the Massachusetts General Hospital between 1989 and 2009. Changes in OCD and major depressive disorder symptom severity were assessed at both the initial and most recent postoperative follow-up by using the Yale-Brown Obsessive Compulsive Scale and the Beck Depression Inventory, respectively. Full and partial OCD symptom responses were defined as Yale-Brown Obsessive Compulsive Scale score reductions of ≥ 35% and 25%-34%, respectively.

RESULTS

Regarding OCD symptom improvement, at the first postoperative follow-up (mean 10.7 months), 35% of patients demonstrated a full response and 7% were partial responders. Thirty patients had a subsequent procedure (repeat cingulotomy or subcaudate tractotomy). By the most recent follow-up (mean 63.8 months), rates climbed to 47% and 22% for full and partial responses, respectively. Of the 24 patients with at least a partial response at initial follow-up, 20 (83%) retained at least a partial response at final follow-up. Comorbid major depressive disorder severity decreased by 17% at the most recent follow-up.

CONCLUSIONS

Limbic system surgery based on initial cingulotomy offers a durable and effective treatment option for appropriately selected patients with severe OCD who have not responded to conventional pharmacotherapy or psychotherapy.

Surgery of the mind, mood, and conscious state: an idea in evolution

Since the beginning of recorded history, humans have sought a physical means of altering disordered behavior and consciousness. This quest has spawned numerous innovations in neurosurgery and the neurosciences, from the earliest prehistoric attempts at trepanation to the electrocortical and anatomic localization of cerebral function that emerged in the 19th century. At the start of the 20th century, the overwhelming social impact of psychiatric illness intersected with the novel but imperfect understanding of frontal lobe function, establishing a decades-long venture into the modern origin of psychosurgery, the prefrontal lobotomy. The subsequent social and ethical ramifications of the widespread overuse of transorbital lobotomies drove psychosurgery to near extinction. However, as the pharmacologic treatment of psychiatric illness was established, numerous concomitant technical and neuroscientific innovations permitted the incremental development of a new paradigm of treating the disordered mind. In this article, we retrospectively examine these early origins of psychosurgery and then look to the recent past, present, and future for emerging trends in surgery of the psyche. Recent decades have seen a revolution in minimalism, noninvasive imaging, and functional manipulation of the human cerebrum that have created new opportunities and treatment modalities for disorders of the human mind and mood. Early contemporary efforts were directed at focal lesioning of abnormal pathways, but deep-brain stimulation now aims to reversibly alter and modulate those neurologic activities responsible for not only psychiatric disorders, but also to modulate and even to augment consciousness, memory, and other elements of cerebral function. As new tools become available, the social and medical impact of psychosurgery promises to revolutionize not only neurosurgery, but also humans' capability for positively impacting life and society.

Cross-species affective functions of the medial forebrain bundle-implications for the treatment of affective pain and depression in humans

Major depression (MD) might be conceptualized as pathological under-arousal of positive affective systems as parts of a network of brain regions assessing, reconciling and storing emotional stimuli versus an over-arousal of parts of the same network promoting separation-distress/GRIEF. In this context depression can be explained as an emotional pain state that is the result of a disregulation of several sub-systems that under physiological conditions are concerned with bodily or emotional homeostasis of the human organism in a social context. Physiologically, homeostasis is maintained by influences of the SEEKING system represented - amongst others - by the medial forebrain bundle (MFB). Neuroimaging studies show that the MFB has a proven access to the GRIEF/Sadness system. A functional decoupling of these systems with a dysfunctional GRIEF pathway might result in MD. Therewith GRIEF and SEEKING/PLEASURE systems play important roles as opponents in maintenance of emotional homeostasis. Chronic electrical modulation of the reward SEEKING pathways with deep brain stimulation might show anti-depressive effects in humans suffering from MD by re-initiating an emotional equilibrium (of higher or lower activity) between these opposing systems.

Tractographic analysis of historical lesion surgery for depression

Various surgical brain ablation procedures for the treatment of refractory depression were developed in the twentieth century. Most notably, key target sites were (i) the anterior cingulum, (ii) the anterior limb of the internal capsule, and (iii) the subcaudate white matter, which were regarded as effective targets. Long-term symptom remissions were better following lesions of the anterior internal capsule and subcaudate white matter than of the cingulum. It is possible that the observed clinical improvements of these various surgical procedures may reflect shared influences on presently unspecified brain affect-regulating networks. Such possibilities can now be analyzed using modern brain connectivity procedures such as diffusion tensor imaging (DTI) tractography. We determined whether the shared connectivities of the above lesion sites in healthy volunteers might explain the therapeutic effects of the various surgical approaches. Accordingly, modestly sized historical lesions, especially of the anatomical overlap areas, were 'implanted' in brain-MRI scans of 53 healthy subjects. These were entered as seed regions for probabilistic DTI connectivity reconstructions. We analyzed for the shared connectivities of bilateral anterior capsulotomy, anterior cingulotomy, subcaudate tractotomy, and stereotactic limbic leucotomy (a combination of the last two lesion sites). Shared connectivities between the four surgical approaches mapped onto the most mediobasal aspects of bilateral frontal lobe fibers, including the forceps minor and the anterior thalamic radiations that contacted subgenual cingulate regions. Anatomically, convergence of these shared connectivities may derive from the superolateral branch of the medial forebrain bundle (MFB), a structure that connects these frontal areas to the origin of the mesolimbic dopaminergic 'reward' system in the midbrain ventral tegmental area. Thus, all four surgical anti-depressant approaches may be promoting positive affect by converging influences onto the MFB.

Deep brain stimulation for obsessive-compulsive disorder: past, present, and future

Obsessive-compulsive disorder (OCD) is a psychiatric illness that can lead to chronic functional impairment. Some patients with severe, chronic OCD have been treated with ablative neurosurgical techniques over the past 4 decades. More recently, deep brain stimulation (DBS) has been investigated as a therapy for refractory OCD, and the procedure was granted a limited humanitarian device exemption by the FDA in 2009. In this article, the authors review the development of DBS for OCD, describe the current understanding of the pathophysiological mechanisms of the disorder and how the underlying neural circuits might be modulated by DBS, and discuss the clinical studies that provide evidence for the use of this evolving therapy. The authors conclude with suggestions for how a combined basic science and translational research approach could drive the understanding of the neural mechanisms underlying OCD as well as the clinical effectiveness of DBS in the setting of recalcitrant disease.

Neurostimulatory and ablative treatment options in major depressive disorder: a systematic review

INTRODUCTION

Major depressive disorder is one of the most disabling and common diagnoses amongst psychiatric disorders, with a current worldwide prevalence of 5-10% of the general population and up to 20-25% for the lifetime period.

HISTORICAL PERSPECTIVE

Nowadays, conventional treatment includes psychotherapy and pharmacotherapy; however, more than 60% of the treated patients respond unsatisfactorily, and almost one fifth becomes refractory to these therapies at long-term follow-up.

NONPHARMACOLOGICAL TECHNIQUES

Growing social incapacity and economic burdens make the medical community strive for better therapies, with fewer complications. Various nonpharmacological techniques like electroconvulsive therapy, vagus nerve stimulation, transcranial magnetic stimulation, lesion surgery, and deep brain stimulation have been developed for this purpose.

DISCUSSION

We reviewed the literature from the beginning of the twentieth century until July 2009 and described the early clinical effects and main reported complications of these methods.

Invasive circuitry-based neurotherapeutics: stereotactic ablation and deep brain stimulation for OCD

Psychiatric neurosurgery, specifically stereotactic ablation, has continued since the 1940s, mainly at a few centers in Europe and the US. Since the late 1990s, the resurgence of interest in this field has been remarkable; reports of both lesion procedures and the newer technique of deep brain stimulation (DBS) have increased rapidly. In early 2009, the US FDA granted limited humanitarian approval for DBS for otherwise intractable obsessive-compulsive disorder (OCD), the first such approval for a psychiatric illness. Several factors explain the emergence of DBS and continued small-scale use of refined lesion procedures. DBS and stereotactic ablation have been successful and widely used for movement disorders. There remains an unmet clinical need: current drug and behavioral treatments offer limited benefit to some seriously ill people. Understandings of the neurocircuitry underlying psychopathology and the response to treatment, while still works in progress, are much enhanced. Here, we review modern lesion procedures and DBS for OCD in the context of neurocircuitry. A key issue is that clinical benefit can be obtained after surgeries targeting different brain structures. This fits well with anatomical models, in which circuits connecting orbitofrontal cortex (OFC), medial prefrontal cortex (mPFC), basal ganglia, and thalamus are central to OCD pathophysiology and treatment response. As in movement disorders, dedicated interdisciplinary teams, here led by psychiatrists, are required to implement these procedures and maintain care for patients so treated. Available data, although limited, support the promise of stereotactic ablation or DBS in carefully selected patients. Benefit in such cases appears not to be confined to obsessions and compulsions, but includes changes in affective state. Caution is imperative, and key issues in long-term management of psychiatric neurosurgery patients deserve focused attention. DBS and contemporary ablation also present different patterns of potential benefits and burdens. Translational research to elucidate how targeting specific nodes in putative OCD circuitry might lead to therapeutic gains is accelerating in tandem with clinical use.

The neural bases of obsessive-compulsive disorder in children and adults

Functional imaging studies have reported with remarkable consistency hyperactivity in the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), and caudate nucleus of patients with obsessive-compulsive disorder (OCD). These findings have often been interpreted as evidence that abnormalities in cortico-basal ganglia-thalamo-cortical loops involving the OFC and ACC are causally related to OCD. This interpretation remains controversial, however, because such hyperactivity may represent either a cause or a consequence of the symptoms. This article analyzes the evidence for a causal role of these loops in producing OCD in children and adults. The article first reviews the strong evidence for anatomical abnormalities in these loops in patients with OCD. These findings are not sufficient to establish causality, however, because anatomical alterations may themselves be a consequence rather than a cause of the symptoms. The article then reviews three lines of evidence that, despite their own limitations, permit stronger causal inferences: the development of OCD following brain injury, pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection, and neurosurgical lesions that attenuate OCD. Converging evidence from these various lines of research supports a causal role for the cortico-basal ganglia-thalamo-cortical loops that involve the OFC and ACC in the pathogenesis of OCD in children and adults.

Neurosurgery for psychiatric disorders: from the excision of brain tissue to the chronic electrical stimulation of neural networks

Neurosurgical treatment for psychiatric disorders has a long and controversial history dating back to antiquity. Both enthusiastic reports and social outcry have accompanied psychosurgical practice, particularly over the last century. Frontal lobotomy has probably been the only medical advance which was first awarded a Nobel prize in medicine and then irreparably stigmatized by scientific rejection and public criticism. In the present paper, the historical milestones of psychosurgery are briefly overviewed. The particular circumstances of the rise and fall of frontal lobotomy are also discussed. Furthermore, the clinical and surgical considerations of the four major psychosurgical procedures which are still in practice are presented. Over the last fifteen years, the advent of deep brain stimulation (DBS) methodology coupled with accurate stereotactic techniques and guided by elaborate neuroimaging methods have revolutionized neurosurgery, particularly for the alleviation of certain disabling movement disorders. Investigationally, chronic electrical stimulation of selected brain structures, clearly implicated in the pathophysiology of neuropsychiatric disorders, has already been applied with promising results. Given the tainted past of psychiatric neurosurgery, modern neuroscientists have to move forward cautiously, in a scientifically justified and ethically approved framework. The transition from the indiscriminate destruction of brain structures to the selected electrical modulation of neural networks lies ahead; contemporary neuroscientists would substantiate this aim but should remind the controversial history of the field.

Neurobiological background for performing surgical intervention in the inferior thalamic peduncle for treatment of major depression disorders

OBJECTIVE

To present a review of evidence for an inhibitory thalamo-orbitofrontal system related to physiopathology of major depression disorders (MDDs) and to postulate that interfering with hyperactivity of the thalamo-orbitofrontal system by means of chronic high-frequency electrical stimulation of its main fiber connection, the inferior thalamic peduncle (ITP), may result in an improvement in patients with MDD.

METHODS

Experimentally, the thalamo-orbitofrontal system has been proposed as part of the nonspecific thalamic system. Under normal conditions, the nonspecific thalamic system induces characteristic electrocortical synchronization in the form of recruiting responses that mimic some sleep stages. It also inhibits input of irrelevant sensory stimuli, thus facilitating the process of selective attention. Permanent disruption of the system, via lesioning or temporary inactivation through cooling of the ITP with cryoprobes, results in a state of hyperkinesia, increased attention, and cortical desynchronization.

RESULTS

Surgical lesioning of the medial part of orbitofrontal cortex and white matter overlying area 13, which includes the ITP, may result in significant improvement in MDD. Imaging studies (functional magnetic resonance imaging and positron emission tomography) consistently demonstrate hyperactivity in the orbitofrontal cortex and midline thalamic regions during episodes of MDD. This hyperactivity decreases with efficient control of MDD by medical treatment, indicating that orbitofrontal cortex and midline thalamic overactivity are related to the depressive condition. Conversely, noradrenergic and serotoninergic systems in the frontal lobes have been implicated in the pathophysiology of MDD. Although noradrenergic receptor density in the frontal lobe is consistently increased in depressed patients who commit suicide, 5-hydroxytryptamine reuptake blockers, which are potent antidepressive drugs, decrease hypermetabolism in the orbital frontal cortex in MDD. Therefore, the serotonin hypothesis for depression postulates that norepinephrine and serotonin in the frontal lobes are required to maintain antidepressive responsiveness. Dysregulation of the secretion of both neurotransmitters initiates overactivity of orbitofrontal cortex, resulting in depression. It is possible that surgical interventions in this region, including electrical stimulation of ITP, disrupt adrenergic and serotoninergic dysregulation in patients with MDD.

CONCLUSION

Circumscribed lesions or electrical stimulation of the ITP, a discrete target easily identified by electrophysiological studies, may improve MDD. Electrical stimulation may have the advantage of being less invasive and more adjustable to patient needs.

Neurosurgical interventions for neuropsychiatric syndromes

Psychosurgical procedures have been used for the treatment of intractable mental illness for more than 50 years. With improvements in surgical techniques, including new implantable stimulators, advances in functional neuroimaging, and progress in our fundamental understanding of the pathophysiology of mental illness there is a renewed interest in neurosurgical treatment of refractory psychiatric illness. This article will review the history of psychosurgery and recent developments in surgical techniques and implantable devices used in this context. The results of psychosurgery for the treatment of several psychiatric conditions and neuropsychiatric symptoms will be presented, including obsessive-compulsive disorder, Tourette's syndrome, depression, anxiety, aggression, self-injurious behavior, and schizophrenia. Lastly, a perspective on the current and future role of psychosurgery for the treatment of mental illnesses will be discussed.

Pathophysiology of obsessive–compulsive disorder

Obsessive-compulsive disorder (OCD) is characterized by repetitive intrusive thoughts and compulsive time-consuming behaviors classified into three to five distinct symptom dimensions including: (1) aggressive/somatic obsessions with checking compulsions; (2) contamination concerns with washing compulsions; (3) symmetry obsessions with counting/ordering compulsions; (4) hoarding obsessions with collecting compulsions; and (5) sexual/religious concerns. Phenomenologically, OCD could be thought of as the irruption of internal signals centered on the erroneous perception that "something is wrong" in a specific situation. This generates severe anxiety, leading to recurrent behaviors aimed at reducing the emotional tension. In this paper, we examine how the abnormalities in brain activity reported in OCD can be interpreted in the light of physiology after consideration of various approaches (phenomenology, neuropsychology, neuroimmunology and neuroimagery) that contribute to proposing the central role of several cortical and subcortical regions, especially the orbitofrontal cortex (OFC), the anterior cingulate cortex (ACC), the dorsolateral prefrontal cortex (DLPC), the head of the caudate nucleus and the thalamus. The OFC is involved in the significance attributed to the consequences of action, thereby subserving decision-making, whereas the ACC is particularly activated in situations in which there are conflicting options and a high likelihood of making an error. The DLPC plays a critical part in the cognitive processing of relevant information. This cortical information is then integrated by the caudate nucleus, which controls behavioral programs. A dysfunction of these networks at one or several stages will result in the emergence and maintenance of repetitive thoughts and characteristic OCD behavior.

Neurosurgery for intractable obsessive-compulsive disorder and depression: critical issues

Intractable OCD and depression cause tremendous suffering in those affected and in their families. The impaired ability to function of those affected imposes a heavy burden on society as a whole. Existing data suggest that lesion procedures offer benefit to a large proportion (ranging from about 35%-70%) of patients with intractable OCD and depression. The literature also suggests that although serious long-term adverse events have occurred, these are relatively infrequent overall. Methodologic limitations of the earlier reports on any of these procedures were described previously in this article. The major academic centers conducting this work have since been obtaining systematic prospective data using modern assessment tools. Nevertheless, even with improved methodologies, more recent studies confront some remaining issues that have been difficult to overcome fully. First, the number of patients who have received any one procedure has been relatively small, constraining statistical power. This limits the ability of researchers to enhance patient selection based on clinical characteristics. This is important, because patients with intractable OCD and depression referred for neurosurgery have high rates of comorbid Axis I diagnoses, personality disorders, and functional impairments, which may have value in predicting response. Other features, such as age of onset, chronicity, and symptom subtypes, may be likewise useful. Another key factor in response may be postoperative management, which has varied most over time but also across patients enrolled in trials. As noted previously, randomized controlled trials of neurosurgical treatment for intractable psychiatric illness have not been reported, although one has been proposed for gamma knife capsulotomy in intractable OCD [23]. The development of deep brain stimulation has also made sham-controlled studies possible and also allows within-patient designs to be considered. Bearing these problems in mind, the literature does provide important guidance on a number of key points, including approaches to referral, patient selection, and the need for long-term prospective follow-up and postoperative management. Nevertheless, important gaps in knowledge remain in all these areas. Research is expected to narrow these gaps in a number of ways, including patient selection, optimizing the procedures themselves, and understanding the mechanisms of therapeutic action. Neuroimaging studies will play a key role in achieving these aims (see the article by Rauch in this issue). So will cross-species translational research on the anatomy and physiology of the pathways implicated in the pathophysiology and response to treatment in these disorders. Future research in psychiatric neurosurgery must proceed cautiously. A recent editorial statement of the OCD-DBS Collaborative Group [26] recommends a minimum set of standards for any multidisciplinary teams contemplating work in this domain. The rationale for those standards is found throughout this issue and is especially developed in the article by Fins. The need for safe and effective therapeutic options for people suffering with these severe illnesses is just as clear. The experience over the last several decades provides grounds for careful optimism that refined lesion procedures or reversible deep brain stimulation may relieve suffering and improve the lives of people with these devastating disorders.

Modern neurosurgery for psychiatric disorders

OBJECTIVE

The evolution, rationale, and results of modern functional neurosurgery to treat psychiatric disorders are documented. The potential benefits of neurosurgical treatment for selected, critically ill, psychiatric patients are considered.

METHODS

The history, anatomic features, and evolution of and contemporary indications for the four currently used procedures (cingulotomy, subcaudate tractotomy, limbic leukotomy, and capsulotomy) are reviewed. Available outcome, neuropsychological assessment, and functional imaging data are presented.

RESULTS

Recently, there has been a renaissance of interest in the surgical treatment of psychiatric disease. Modern psychiatric neurosurgical procedures are quite safe, with extremely low surgical mortality rates and transient postoperative morbidity. In selected cases, patients with conditions that had previously been completely refractory to comprehensive medical and behavioral intervention demonstrated significant improvement. This improvement was usually observed in the absence of long-term adverse neuropsychological consequences.

CONCLUSION

Recent outcome studies, together with advances in neurobiology, psychiatry, functional imaging, and stereotaxy, support the further investigation of modern functional neurosurgical procedures to treat psychiatric disorders and their application for a subset of psychiatric patients with conditions refractory to all other therapies.

The role of psychosurgery in the treatment of selected cases of refractory schizophrenia: a reappraisal

Prefrontal lobotomy (i.e. leukotomy) was widely performed for the treatment of schizophrenia during the late 1930s and 1940s but met with growing disrepute after the introduction of effective antipsychotic agents in the early 1950s. While non-invasive methods of treatment are undeniably preferable to somatic interventions for the management of psychiatric illnesses, there nevertheless continues to be a valid role for leukotomy in the treatment of patients with severe, chronic, refractory schizophrenia, particularly when the patient poses a risk to himself and/or to society. The present article traces the history of leukotomy in the treatment of schizophrenia, and reviews the author's experience with this surgical procedure in 16 patients who fulfilled the above criteria and underwent leukotomy during the years spanning 1985 1996. This operation reduced aggression and/or produced marked to slight improvement in all patients, and in no case led to adverse consequences. Thus, leukotomy is recommended as a legitimate treatment modality in selected patients with schizophrenia.

Treatment of obsessive-compulsive disorder by psychosurgery

We report a longitudinal study of 26 patients with medically intractable obsessive-compulsive disorder (OCD) who were treated with psychosurgery and had a comprehensive follow-up for a mean 10 years. Seventeen patients had combined orbitomedial and cingulate lesions, 6 cingulate lesions only and 3 orbitomedial lesions only. Eighteen patients were interviewed personally and lesions verified on magnetic resonance imaging scans in fourteen. On a 6-point global rating scale, 10 (38%) patients had obvious improvement, another 6 (23%) showed mild improvement of doubtful clinical value, and the remaining 10 showed either no change (n = 6; 23%) or were judged to be worse (n = 4; 15%). Both obsessive and compulsive symptoms improved, and this change was independent of the changes in anxiety and depression scores. No significant predictors of improvement were identified. Patients with cingulate lesions only fared worse. Eight patients who had a second operation did not show much improvement. A comparison of a subgroup of patients with 10 matched nonsurgical OCD controls supported the contention that the improvement in OCD was attributable to the psychosurgery. Important adverse effects in the stereotactic surgery group (n = 20) were epilepsy (1 patient) and personality change (2 patients). The psychosurgery group performed relatively poorly on the Wisconsin Card Sort Test but did not show any deterioration in Wechsler Intelligence and Memory scores.

Delayed emergence of obsessive-compulsive neurosis following head injury. Case report and review of its theoretical implications

A patient with obsessive-compulsive neurosis arising six months after minor head injury is described. The theoretical implications of this case are discussed. A neuropsychological model to explain the onset of the disorder in this and previously reported cases is suggested.

The effects on intellectual functioning of open prefrontal leucotomy

The Wechsler Adult Intelligence Scale and the Wechsler Memory Scale were administered to 32 patients both before and six months after they received open prefrontal leucotomies. The preoperative and postoperative test results are compared, consideration being given to individual patients as well as to the group. The mean results for the group provide no evidence of any post-operative intellectual deterioration. However, it seems probable that in individual cases such deterioration occurred. In most of these cases brain damage would appear to be responsible, and the ability "to comprehend and size up a total situation" is seen as the area of functioning primarily affected.

Stereotactic limbic leucotomy--a follow-up at 16 months

Sixty-six patients were assessed clinically, psychologically and physiologically before operation, at six weeks and at a mean of 16 months following stereotactic limbic leucotomy. Seventy-three per cent were clinically improved at six weeks and 76 per cent at 16 months. In obsessional neurosis, 89 per cent of patients showed definite clinical improvement at 16 months; in chronic anxiety, 66 per cent were improved; in depression, 78 per cent; and in the small number of schizophrenics treated the improvement rate was over 80 per cent. Self-assessment and observer-assessment questionaires and scales measuring Depression, Anxiety, Neuroticism, Hysterical symptoms and Obsessional symptoms and traits all showed highly significant reductions of mean scores at 16 months. There was no fall-off in intelligence, and adverse effects were minimal. Limbic leucotomy, with its enhanced accuracy and safety, compares very favourably with similarly assessed, more extensive 'free-hand' procedures, and in obsessional neurosis and chronic anxiety the results are superior.

Aspects of the psychology and epidemiology of rheumatoid disease

In a prospective study of rheumatoid disease (RD) clinical, serological, radiological, and biochemical factors were assessed on 102 patients and scores obtained on the Middlesex Hospital Questionnaire (MHQ). Patients with early RD had MHQ scores closely resembling those in the normal population. Using a new clinical prognostic index, patients who develop severe RD tended to have low scores at initial testing on the MHQ. Patients whose serum was positive for rheumatoid factor also tended to have low scores on the MHQ. Together these findings suggest a possible subclassification of RD into a less severe form in which psychosocial factors may be important, and a more severe form in which heredity or some other constitutional factor (or factors) may be important, rheumatoid factor acting as a 'marker'.

Psychosurgery and the limbic system

The limbic system can be considered to consist of a central ‘core’ from which three well-defined circuits emerge. These are the Papez or medial circuit, the basolateral circuit and the defence reaction circuit. The functions of the primitive limbic brain are modulated by a higher order control—the frontal lobe. Emotional responses and physiological changes have been obtained by stimulation of fronto-limbic pathways and limbic circuits and these have been used for location of target sites in psychosurgery. For the relief of intractable depression and anxiety, lesions are generally made in the lower medial quadrant or posteroorbital part of the frontal lobe, where there is a concentration of fronto-limbic connections. In primary obsessional neurosis lesions at this site produce less satisfactory results, but these illnesses may be helped by lesions in the cingulate gyrus, which is part of the Papez circuit. Patients with epilepsy and aggressive outbursts may respond to temporal lobotomy, or to operations, such as amygdalotomy, where lesions are placed in the defence reaction circuit.

Stereotactic limbic leucotomy--a follow-up study of thirty patients

This prospective study reports the results of stereotactic limbic leucotomy at a mean of 17 months following surgery. Clinical improvement had occurred in twenty-four (80%) of the patients, fifteen (50%) of them being symptom free or much improved. Fourteen of sixteen patients suffering from obsessional neurosis were improved, as were five of seven with chronic anxiety and the degree of improvement at 17 months was superior to that at 6 weeks. Psychometric scores of anxiety, obsessions and neuroticism were all significantly reduced at 17 months. The mean depression scores were also significantly reduced and this result was superior to that reported in a previous study of ‘free-hand’ operations.

Adverse effects were not a problem following limbic leucotomy. Emotional blunting, disinhibition, post-operative epilepsy and excessive weight gain were not encountered, and intelligence was unaffected by the operation. Limbic leucotomy is a much more limited and precise procedure than older ‘free-hand’ operations which we have studied, but its therapeutic effects are comparable and in obsessional neurosis, superior.