Utility of foramen ovale electrodes in mesial temporal lobe epilepsy.

Objectives: To determine the ability of foramen ovale electrodes (FOEs) to localize epileptogenic foci after inconclusive noninvasive investigations in patients with suspected mesial temporal lobe epilepsy (MTLE).

Methods: We identified patients with medically intractable epilepsy who had undergone FOE investigation for initial invasive monitoring at our institution between 2005 and 2012. Indications for initiating FOE investigation were grouped into four categories: (1) bilateral anterior temporal ictal activity on scalp electroencephalography (EEG), (2) unclear laterality of scalp EEG onset due to muscle artifact or significant delay following clinical manifestation, (3) discordance between ictal and interictal discharges, and (4) investigation of a specific anatomic abnormality or competing putative focus.

Studying task-related activity of individual neurons in the human brain.

Single-neuronal studies remain the gold standard for studying brain function. Here we describe a protocol for studying task-related single-neuronal activity in human subjects during neurosurgical procedures involving microelectrode recordings. This protocol has two phases: a preoperative phase and an intraoperative phase.

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.

Postoperative intensive care unit requirements after elective craniotomy.

Objective: Commonly, patients undergoing craniotomy are admitted to an intensive care setting postoperatively to allow for close monitoring. We aim to determine the frequency with which patients who have undergone elective craniotomies require intensive care unit (ICU)-level interventions or experience significant complications during the postoperative period to identify a subset of patients for whom an alternative to ICU-level care may be appropriate.

Methods: Following Institutional Review Board approval, a prospective, consecutive cohort of adult patients undergoing elective craniotomy was established at the Massachusetts General Hospital between the dates of April 2010 and March 2011.

Encoding of rules by neurons in the human dorsolateral prefrontal cortex.

We use rules to extend learned behavior beyond specific instances to general scenarios. The prefrontal cortex (PFC) is thought to play an important role in representing rules, as evidenced by subjects who have difficulty in following rules after PFC damage and by animal studies demonstrating rule sensitivity of individual PFC neurons. How rules are instantiated at the single-neuronal level in the human brain, however, remains unclear.

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.

Human dorsal anterior cingulate cortex neurons mediate ongoing behavioural adaptation.

The ability to optimize behavioural performance when confronted with continuously evolving environmental demands is a key element of human cognition. The dorsal anterior cingulate cortex (dACC), which lies on the medial surface of the frontal lobes, is important in regulating cognitive control. Hypotheses about its function include guiding reward-based decision making, monitoring for conflict between competing responses and predicting task difficulty.

Single-neuron responses in the human nucleus accumbens during a financial decision-making task.

Linking values to actions and evaluating expectations relative to outcomes are both central to reinforcement learning and are thought to underlie financial decision-making. However, neurophysiology studies of these processes in humans remain limited. Here, we recorded the activity of single human nucleus accumbens neurons while subjects performed a gambling task.

Transsphenoidal surgery for cushing disease after nondiagnostic inferior petrosal sinus sampling.

Background: Inferior petrosal sinus sampling (IPSS) is a useful technique for confirming a pituitary source of adrenocorticotropic hormone (ACTH) overproduction in Cushing disease. Uncertainty remains regarding the appropriate course of therapy when an ectopic tumor is predicted by IPSS but none can be found and in circumstances when the procedure cannot be successfully completed owing to technical or anatomic limitations.

Objective: To determine an appropriate course of action after nondiagnostic IPSS.

Glioblastoma multiforme and cerebral cavernous malformations: intersection of pathophysiologic pathways.

Cerebral cavernous malformations (CCM) are known to occur in both sporadic and familial forms. To date, there has been no identified association of CCM with glioblastoma multiforme. We present a 69-year-old woman with a 14 year history of multiple CCM who developed progressive aphasia.

Intraspinal migration of a clavicular Steinmann pin: case report and management strategy.

Spine injury resulting from migration of previously implanted appendicular skeleton fixation hardware is rare. We present a 41-year-old man who had Steinmann fixation pins placed for a left clavicular fracture 2 years prior. He presented with a burning sensation over his biceps bilaterally and numbness over the left anterior chest and abdomen following a significant blunt traumatic injury.

Interfacility helicopter ambulance transport of neurosurgical patients: observations, utilization, and outcomes from a quaternary level care hospital.

Background: The clinical benefit of helicopter transport over ground transportation for interfacility transport is unproven. We sought to determine actual practice patterns, utilization, and outcomes of patients undergoing interfacility transport for neurosurgical conditions.

Methodology/principal Findings: We retrospectively examined all interfacility helicopter transfers to a single trauma center during 2008.

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.

A microwell array system for stem cell culture.

Directed embryonic stem (ES) cell differentiation is a potentially powerful approach for generating a renewable source of cells for regenerative medicine. Typical in vitro ES cell differentiation protocols involve the formation of ES cell aggregate intermediates called embryoid bodies (EBs). Recently, we demonstrated the use of poly(ethylene glycol) (PEG) microwells as templates for directing the formation of these aggregates, offering control over parameters such as size, shape, and homogeneity.