Reconciling Functional MRI Findings With Intraoperative Anatomy in Brain Tumor Surgery: Stereotactic-Guided Resection of Glioma in Broca's Area.

Stereotactic navigation and functional magnetic resonance imaging (fMRI) are increasingly used as important tools for intraoperative guidance and preoperative mapping for lesions in eloquent areas. We report a case in which a WHO grade II oligodendroglioma in Broca's area with functional activation was successfully resected with the support of blood-oxygen-level-dependent imaging (BOLD)-fMRI mapping in a patient who refused an awake craniotomy. This case highlights key principles of tumor surgery navigation. Specifically, it calls into question the utility of awake craniotomy in this modern era. Ultimately, fMRI is an important tool for tumor resections and can limit the need for more expensive or invasive measures.

Prospective Evaluation of Ventriculostomy Infections.

INTRODUCTION: Hospital-acquired infections associated with external drainage of ventricular cerebrospinal fluid (CSF) are a significant source of concern for the patients and the provider team alike. Traditional rates of ventriculostomy infection range from 10-17% in a time-dependent fashion. Changing physician and nursing practices fueled this concern over infections.  OBJECTIVE: We sought to prospectively identify the risk factors associated with ventriculostomy infections as part of a quality assurance project.  METHODS: One hundred consecutive patients were evaluated and data were collected on 91. The primary indications for ventriculostomy were subarachnoid hemorrhage (46%), intracerebral hemorrhage (24%), and trauma (22%). Variables prospectively evaluated included pre-incision antibiotics, sterile technique bundling, setting of placement (operating room versus intensive care unit), experience of operator (attending, resident, or physician assistant), catheter type (antibiotic impregnated or not), use of a post-insertion dressing, and in-dwell time of the catheter.  RESULTS: There was only one infection in 91 patients (1.1%). This infection occurred in a patient without an antibiotic-impregnated catheter that was inserted by a resident physician. Compliance with pre-insertion antibiotics was very high, but most other variables had modest deviations in compliance. CONCLUSION: Infection rate related to external ventricular drainage is very low. Our data suggest that non-antibiotic impregnated catheters may be associated with infection, but that other variables thought to be critical may be of less value.

Magnetic imaging: a new tool for UK national nuclear security.

Combating illicit trafficking of Special Nuclear Material may require the ability to image through electromagnetic shields. This is the case when the trafficking involves cargo containers. Thus, suitable detection techniques are required to penetrate a ferromagnetic enclosure. The present study considers techniques that employ an electromagnetic based principle of detection. It is generally assumed that a ferromagnetic metallic enclosure will effectively act as a Faraday cage to electromagnetic radiation and therefore screen any form of interrogating electromagnetic radiation from penetrating, thus denying the detection of any eventual hidden material. In contrast, we demonstrate that it is actually possible to capture magnetic images of a conductive object through a set of metallic ferromagnetic enclosures. This validates electromagnetic interrogation techniques as a potential detection tool for National Nuclear Security applications.

Spontaneous Rupture, Disappearance, and Reaccumulation of a Rathke's Cleft Cyst.

Rathke's cleft cysts (RCCs) are benign epithelium-lined intrasellar cysts containing mucoid material and are believed to originate from the remnants of Rathke's pouch. Most are asymptomatic but may cause symptoms secondary to compression of adjacent structures such as visual disturbances and endocrinopathies, especially hypopituitary. Furthermore, inflammation such as an aseptic meningitis syndrome may be associated with these tumors, presumably resulting from leakage of cyst material into the subarachnoid space. We present a unique case of spontaneous rupture and complete disappearance of a known sella-suprasellar cyst associated with a severe headache syndrome, followed by cyst reaccumulation requiring surgery. Although this phenomenon is well accepted, to our knowledge, this is the first report of the complete disappearance of a Rathke's cyst presenting with the classic syndrome. Furthermore, it was remarkable how quickly it recurred and became symptomatic, providing evidence that an "empty sella syndrome" may indeed need clinical follow-up.

Pituitary apoplexy associated with anterior communicating artery aneurysm and aberrant blood supply.

Pituitary apoplexy is an uncommon condition typically caused by acute, hemorrhagic expansion of the pituitary gland in patients with an adenoma that undergoes infarction. Although various risk factors have been described, the vascular events leading to apoplexy are not well understood. Disruption of microvascular blood flow is a well-known cause of morbidity from hemorrhage of an intracranial aneurysm, but pituitary apoplexy is rarely associated with aneurysmal subarachnoid hemorrhage. We report here a 46-year-old woman with pituitary apoplexy who developed subarachnoid hemorrhage from rupture of an anterior communicating artery aneurysm. Intraoperatively, she was found to have an unusual, large recurrent artery originating at the junction of the aneurysm and the A2 segment of the anterior cerebral artery that traveled to the suprasellar cistern and along the pituitary stalk. This recurrent hypophyseal artery established a direct vascular relationship between an intracerebral aneurysm and the pituitary gland.

The nuclear receptor CAR is a regulator of thyroid hormone metabolism during caloric restriction.

The orphan nuclear receptor CAR (NR1I3) has been characterized as a central component in the coordinate response to xenobiotic and endobiotic stress. In this study, we demonstrate that CAR plays a pivotal function in energy homeostasis and establish an unanticipated metabolic role for this nuclear receptor. Wild-type mice treated with the synthetic CAR agonist 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP) exhibited decreased serum concentration of the thyroid hormone (TH) thyroxine (T(4)). However, treatment of Car(-/-) mice with TCPOBOP failed to elicit these changes. To examine whether CAR played a role in the regulation of TH levels under physiological conditions, wild-type and Car(-/-) mice were fasted for 24 h, a process known to alter TH metabolism in mammals. As expected, the serum triiodothyronine and T(4) concentrations decreased in wild-type mice. However, triiodothyronine and T(4) levels in fasted Car(-/-) mice remained significantly higher than those in fasted wild-type animals. Concomitant with the changes in serum TH levels, both CAR agonist treatment and fasting induced the expression of CAR target genes (notably, Cyp2b10, Ugt1a1, Sultn, Sult1a1, and Sult2a1) in a receptor-dependent manner. Importantly, the Ugt1a1, Sultn, Sult1a1, and Sult2a1 genes encode enzymes that are capable of metabolizing TH. An attenuated reduction in TH levels during fasting, as observed in Car(-/-) mice, would be predicted to increase weight loss during caloric restriction. Indeed, when Car(-/-) animals were placed on a 40% caloric restriction diet for 12 weeks, Car(-/-) animals lost over twice as much weight as their wild-type littermates. Thus, CAR participates in the molecular mechanisms contributing to homeostatic resistance to weight loss. These data imply that CAR represents a novel therapeutic target to uncouple metabolic rate from food intake and has implications in obesity and its associated disorders.

Neuroprotection by the stable nitroxide 3-carbamoyl-proxyl during reperfusion in a rat model of transient focal ischemia.

OBJECT: Nitroxides mimic superoxide dismutase (SOD) biochemically and may prevent free radical oxidative injury in settings in which endogenous SOD is overwhelmed. The authors have previously shown the efficacy of a nitroxide, Tempol, in reducing stroke infarct size. Of the nitroxides, 3-carbamoyl-proxyl (3-CP) is especially promising for clinical use, because it does not cause hypotension in animals. Its efficacy in brain ischemia, however, is untested. The goal of this study was to ascertain whether 3-CP would reduce brain damage in a rat ischemia-reperfusion model. METHODS: The authors performed a blinded, dose-response study of the effect of different amounts of 3-CP (1, 10, and 100 mg/kg) on infarct size at 24 hours after focal ischemia and reperfusion. The 3-CP was given intravenously during reperfusion, which followed 1 hour of reversible ischemia induced by a thread placed intraluminally in the middle cerebral artery of rats. Brain infarcts, measured with 2,3,5-triphenyltetrazolium chloride staining in six 3-CP groups, were compared with those measured in controls (animals given an equal volume of saline). Edema-corrected infarct sizes (mean +/- standard deviation) were as follows: 146 +/- 64 mm3 in controls; 107 +/- 18 mm3 in rats given 1 mg/kg 3-CP; 40 +/- 20 mm3 in those given 10 mg/kg 3-CP; and 44 +/- 17 mm3 in those given 100 mg/kg 3-CP. A statistically significant reduction in infarct size was achieved in the 10- and 100-mg/kg 3-CP-treated groups (p < 0.01). A reduction in infarct size was also seen in the 1 mg/kg 3-CP-treated group, but this did not reach statistical significance. The authors observed no effects of 3-CP on blood pressure or brain temperature. CONCLUSIONS: Given at reperfusion, 3-CP significantly decreases brain infarct size at doses of 10 and 100 mg/kg without causing hypotension. The authors found that 3-CP is well suited for further laboratory and clinical use in brain ischemia and reperfusion.