Bruce H. Price

TDP-43 Proteinopathy and Motor Neuron Disease in Chronic Traumatic Encephalopathy

Epidemiological evidence suggests that the incidence of amyotrophic lateral sclerosis is increased in association with head injury. Repetitive head injury is also associated with the development of chronic traumatic encephalopathy (CTE), a tauopathy characterized by neurofibrillary tangles throughout the brain in the relative absence of &bgr;-amyloid deposits. We examined 12 cases of CTE and, in 10, found a widespread TAR DNA-binding protein of approximately 43kd (TDP-43) proteinopathy affecting the frontal and temporal cortices, medial temporal lobe, basal ganglia, diencephalon, and brainstem. Three athletes with CTE also developed a progressive motor neuron disease with profound weakness, atrophy, spasticity, and fasciculations several years before death. In these 3 cases, there were abundant TDP-43-positive inclusions and neurites in the spinal cord in addition to tau neurofibrillary changes, motor neuron loss, and corticospinal tract degeneration. The TDP-43 proteinopathy associated with CTE is similar to that found in frontotemporal lobar degeneration with TDP-43 inclusions, in that widespread regions of the brain are affected. Akin to frontotemporal lobar degeneration with TDP-43 inclusions, in some individuals with CTE, the TDP-43 proteinopathy extends to involve the spinal cord and is associated with motor neuron disease. This is the first pathological evidence that repetitive head trauma experienced in collision sports might be associated with the development of a motor neuron disease.

Cerebral metabolic correlates as potential predictors of response to anterior cingulotomy for obsessive compulsive disorder.

BACKGROUND As interventions for severe, treatment-refractory obsessive compulsive disorder (OCD), neurosurgical procedures are associated with only modest efficacy. The purpose of this study was to identify cerebral metabolic correlates as potential predictors of treatment response to anterior cingulotomy for OCD. METHODS Clinical data were analyzed in the context of a retrospective design. Subjects were 11 patients who underwent stereotactic anterior cingulotomy for OCD. Symptom severity was measured using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) before and at approximately 6 months postoperative. Preoperative F-18-fluorodeoxyglucose-positron emission tomography (FDG-PET) data were available. Statistical parametric mapping methods were used to identify loci of significant correlation between preoperative regional cerebral metabolism and postoperative reduction in Y-BOCS scores. RESULTS One locus within right posterior cingulate cortex was identified, where preoperative metabolism was significantly correlated with improvement in OCD symptom severity following cingulotomy. Specifically, higher preoperative rates of metabolism at that locus were associated with better postoperative outcome. CONCLUSIONS A possible predictor of treatment response was identified for patients with OCD undergoing anterior cingulotomy. Further research, utilizing a prospective design, is indicated to determine the validity and reliability of this finding. If confirmed, an index for noninvasively predicting response to cingulotomy for OCD would be of great value.

Pharmacotherapies for Alzheimer's disease: Beyond cholinesterase inhibitors

Alzheimers disease (AD) is the most common cause of memory impairment and dementia in the elderly. AD is pathologically characterized by extracellular deposits of beta-amyloid (Aβ) peptide, neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau, neuronal loss, and neurotransmitter dysfunction. Clinically, AD is characterized by progressive cognitive decline that usually starts with memory impairment and progresses to cause a more generalized cognitive dysfunction, behavioral dysregulation, and neuropsychiatric symptoms. These symptoms collectively lead to a progressive and relentless decline in the ability to perform functions of daily living, eventually leading to total incapacitation. The incidence and prevalence of AD are expected to exponentially increase with the aging of the population. Currently approved treatments, including the acetylcholinesterase inhibitors (AChEIs) donepezil, galantamine and rivastigmine, and the N-methyl-D-aspartate (NMDA) antagonist memantine, do not halt the progression of the disease, and have provided marginal therapeutic benefits. Accordingly, there is an urgent need to develop novel and effective medications for AD that go beyond AChEIs and NMDA antagonists. Modern research has focused on discovering effective disease-modifying therapies, which specifically target the pathophysiologic cascade, hoping to delay the onset of the disease and slow its progression. In this review, different pharmacological drugs and therapeutic approaches will be discussed, with an emphasis on novel therapies that are currently being investigated in clinical trials.

Magnetic Resonance Image-guided Stereotactic Cingulotomy for Intractable Psychiatric Disease

WE DESCRIBE THE modern operative technique of magnetic resonance (MR) image-guided stereotactic cingulotomy and discuss the indications, results, and complications of this procedure. A retrospective analysis of psychiatric outcome was performed for 34 patients with intractable major affective disorder and/or obsessive-compulsive disorder who underwent MR image-guided stereotactic cingulotomy since 1991. Fourteen patients underwent multiple cingulotomies (50 total procedures). Overall, 38% of the patients were classified as responders, 23% as possible responders, and 38% as nonresponders. Of the patients who did not respond to initial cingulotomies and who underwent multiple cingulotomies, 36% became responders, 36% possible responders, and 28% nonresponders. There were no deaths or long-term side effects related to the procedure. The therapeutic results of MR image-guided stereotactic cingulotomy are similar to the results of earlier methods of cingulotomy, and the use of MR imaging offers substantial technical advantages. This procedure also compares favorably with other neurosurgical procedures performed for intractable psychiatric disease with a low rate of undesired side effects. Cingulotomy is safe and well tolerated, with over one-third of the patients demonstrating significant improvement ; however, prospective long-term follow-up studies are needed to further define the role of surgery in treating intractable psychiatric disease.

Deficits in visual cognition and attention following bilateral anterior cingulotomy

A series of eight tests of visual cognitive abilities was used to examine pre- to post-operative performance changes in a patient receiving bilateral anterior cingulotomy. Compared with a set of eight matched control participants, post-operatively, the patient exhibited deficits in (a) the ability to sequence novel cognitive operations required to generate multipart images or rotate perceptual stimuli; (b) the ability to search for, select, and compare images of objects when the instructions did not specify precisely which objects should be visualized; and, (c) the ability to select a controlled and unpracticed response over an automatic one. Other imagery and cognitive tasks were not affected. Results are consistent with the hypothesis that anterior cingulate cortex is a component of an executive control system. One of the anterior cingulates roles may be to monitor on-line processing and signal the motivational significance of current actions or cognitions.

Magnetic Resonance Imaging-guided Stereotactic Limbic Leukotomy for Treatment of Intractable Psychiatric Disease

OBJECTIVE To assess the efficacy and complication rates of magnetic resonance imaging-guided stereotactic limbic leukotomy for the treatment of intractable major depressive disorder (MDD) and obsessive-compulsive disorder (OCD). METHODS We conducted preoperative evaluations and postoperative follow-up assessments of efficacy and complications for 21 patients who underwent limbic leukotomy. Efficacy was based on physician- and patient-rated global assessments of functioning, as well as evaluations using disease-specific rating scales commonly used in studies of MDD and OCD. RESULTS The mean time from limbic leukotomy to follow-up assessment was 26 months. On the basis of standard outcome measures, 36 to 50% of patients were considered to be treatment responders. Although permanent surgical morbidity was rare, there were reports of postoperative sequelae, including apathy, urinary incontinence, and memory complaints, which occurred in a substantial minority of cases. CONCLUSION For this cohort of 21 patients with chronic severe MDD or OCD, who had experienced failure with an exhaustive array of previous treatments, limbic leukotomy was associated with substantial benefit for 36 to 50%. This rate is comparable to those of previous studies of limbic system surgery and indicates that limbic leukotomy is a feasible treatment option for severe, treatment-refractory MDD or OCD. Adverse consequences associated with the procedure included affective, cognitive, and visceromotor sequelae, which were generally transient.

Psychiatric manifestations of right hemisphere infarctions.

Five right-handed patients (aged 45 to 78 years) developed acute psychotic disturbances in conjunction with infarcts in the right hemisphere. Their presentation was marked by agitation, inattention, suspiciousness, paranoid delusions, hallucinations, and lack of appropriate concern. Several of these patients initially received primary psychiatric diagnoses. Although neurological findings indicative of right hemisphere involvement could also be elicited, these were generally overshadowed by the more dramatic behavioral alterations. The electroencephalogram and computerized axial tomography were positive in most cases. These cases demonstrate that the possibility of a right hemisphere lesion needs to be entertained in patients who present with an atypical psychotic episode.

The Use of Palliative Sedation for Existential Distress: A Psychiatric Perspective

&NA; This article introduces a structure for standardization in the ongoing debate about the application of palliative sedation for psychological and existential suffering at the end of life. We differentiate the phenomenon of existential distress from the more general one of existential suffering, defining existential distress as a special case of existential suffering that applies to persons with terminal illness. We introduce both a clinical classification system of existential distress based on proximity to expected death and a decision‐making process for considering palliative sedation (represented by the mnemonic, TIRED). Neuropsychiatric clinical cases will be used to demonstrate some of the concepts and ethical arguments.

Sensory alien hand syndrome: case report and review of the literature

An 81 year old right handed woman developed a left alien hand syndrome characterised by involuntary movements of choking and hitting the face, neck, and shoulder. The patient showed multiple disorders of primary sensation, sensory processing, hemispatial attention, and visual association, as well as a combination of sensory, optic, and cerebellar ataxia (triple ataxia) of the left arm in the absence of motor neglect or hemiparesis. Imaging studies disclosed subacute infarction in the right thalamus, hippocampus, inferior temporal lobes, splenium of corpus callosum, and occipital lobe due to right posterior cerebral artery occlusion. This rare syndrome should be considered as a “sensory” or “posterior” form of the alien hand syndrome, to be distinguished from the “motor” or “anterior” form described more commonly.

The functional neuroanatomy of decision-making.

Decision-making is a complex executive function that draws on past experience, present goals, and anticipation of outcome, and which is influenced by prevailing and predicted emotional tone and cultural context. Functional imaging investigations and focal lesion studies identify the orbitofrontal, anterior cingulate, and dorsolateral prefrontal cortices as critical to decision-making. The authors review the connections of these prefrontal regions with the neocortex, limbic system, basal ganglia, and cerebellum, highlight current ideas regarding the cognitive processes of decision-making that these networks subserve, and present a novel integrated neuroanatomical model for decision-making. Finally, clinical relevance of this circuitry is illustrated through a discussion of frontotemporal dementia, traumatic brain injury, and sociopathy.