Sudden death in a 27-year-old man with Chiari I malformation.

We present a case of a witnessed sudden death of a 27-year-old adult man with no antecedent trauma who subsequently was found to have a previously undiagnosed Chiari I malformation. Cases of sudden unprovoked respiratory collapse in children and adults with Chiari I malformation have been well documented, leading to death in some children. There have also been rare examples of sudden death in adults with Chiari I malformation; however, these decedents experienced recent trauma. This is a unique example of a witnessed sudden death of an adult with previously undiagnosed Chiari I malformation in the absence of trauma.

Muscle Viability Revisited: Are We Removing Normal Muscle? A Critical Evaluation of Dogmatic Debridement.

PURPOSE: Determination of muscle viability during debridement is a subjective process with significant consequences. Evaluating muscle color, consistency, contractility, and capacity to bleed (the 4 Cs) was established by a study performed half a century ago. This work reinvestigates the utility of the 4 Cs using current histopathologic techniques. METHODS: After institutional review board approval, 36 biopsies were prospectively collected at a level-1 trauma center from 20 patients undergoing a debridement for open fracture (81%), compartment syndrome (11%), infection (5%), or crush injury (3%). Surgeons graded the biopsies using the 4 Cs, and provided their overall impression as healthy, borderline, or dead. Blinded pathological analysis was performed on each specimen. A correlation between the 4 Cs and surgeon impression with histopathological diagnosis was sought through a univariate statistical analysis. RESULTS: The surgeon's impression was dead muscle in 25 specimens, borderline in 10, and healthy in 1. Pathological analysis of the 35 specimens considered as dead or borderline muscle by the surgeon demonstrated normal muscle or mild interstitial inflammation in 21 specimens (60%). Color (P = 0.07), consistency (P = 0.12), contractility (P = 0.51), capacity to bleed (P = 0.07), and surgeon impression (P = 0.50) were unable to predict histologic appearance. CONCLUSIONS: Neither the 4 Cs nor the surgeon's impression correlate with histological findings regarding muscle viability. In 72% of specimens, the treating surgeon's gross assessment differed from the histopathologic appearance. Although the fate of the debrided muscle remains unclear if left in situ, these results raise questions regarding current practices, including the possibility that surgeons are debriding potentially viable muscle. LEVEL OF EVIDENCE: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Transplacental transmission of metastatic melanoma to the posterior fossa. Case report.

The authors describe the first documented case of transplacental transmission of metastatic melanoma to the neuraxis. The patient was a 7-month-old boy who presented with signs and symptoms of elevated intracranial pressure. Magnetic resonance imaging revealed an inhomogeneously enhancing posterior fossa mass measuring 5 x 5 x 6 cm and filling the fourth ventricle. A posterior fossa craniotomy was performed. Pathological studies confirmed the presence of a metastatic melanoma that was pathologically identical to that of his mother. The boy received aggressive chemotherapy and underwent an additional resection. He also required a ventriculoperitoneal shunt for treatment of his hydrocephalus. He lived longer than any other patient with transplacental transmission of metastatic melanoma but ultimately died of the disease, 18 months after his initial presentation.

A rare case of malignant pediatric ectomesenchymoma arising from the falx cerebri.

Malignant ectomesenchymoma is a rare tumor arising from mature ganglion cells with immature myogenous elements, with only 4 pediatric intracranial cases having been previously reported. The authors report a rare case of intracranial malignant ectomesenchymoma originating from the falx cerebri in a 10-year-old boy. The patient presented with a 2-week history of headache, nausea, and blurry vision, with mild lateral gaze diplopia. A CT scan revealed a solitary 7.2 × 3.8-cm dural-based mass that extended along the falx. No metastatic disease was identified, and the lesion was grossly resected without complication. Pathological investigation identified single and small groups of cells in a myxoid background, with polygonal or spindle-shaped cells containing eccentric nuclei and prominent nucleoli. Immunohistochemical staining of some cells was positive for smooth-muscle actin, CD99, and vimentin, whereas other cells (often process forming) were positive for S100 protein, synaptophysin, and neurofilament protein. Staining was negative for CD138, CD45, α-fetoprotein, CK AE1/3, glial fibrillary acidic protein, CK7, CK20, CD31, CD34, myoD, and desmin. Normal immunopositivity was seen for INI-1. The Ki 67 immunostaining had < 25% reactivity. The patient was treated with a sarcoma-based chemotherapy regimen and radiation to the craniospinal axis, and was found to be without recurrence or metastatic disease at 20 months.

Levetiracetam enhances p53-mediated MGMT inhibition and sensitizes glioblastoma cells to temozolomide.

Antiepileptic drugs (AEDs) are frequently used to treat seizures in glioma patients. AEDs may have an unrecognized impact in modulating O(6)-methylguanine-DNA methyltransferase (MGMT), a DNA repair protein that has an important role in tumor cell resistance to alkylating agents. We report that levetiracetam (LEV) is the most potent MGMT inhibitor among several AEDs with diverse MGMT regulatory actions. In vitro, when used at concentrations within the human therapeutic range for seizure prophylaxis, LEV decreases MGMT protein and mRNA expression levels. Chromatin immunoprecipitation analysis reveals that LEV enhances p53 binding on the MGMT promoter by recruiting the mSin3A/histone deacetylase 1 (HDAC1) corepressor complex. However, LEV does not exert any MGMT inhibitory activity when the expression of either p53, mSin3A, or HDAC1 is abrogated. LEV inhibits malignant glioma cell proliferation and increases glioma cell sensitivity to the monofunctional alkylating agent temozolomide. In 4 newly diagnosed patients who had 2 craniotomies 7-14 days apart, prior to the initiation of any tumor-specific treatment, samples obtained before and after LEV treatment showed the inhibition of MGMT expression. Our results suggest that the choice of AED in patients with malignant gliomas may have an unrecognized impact in clinical practice and research trial design.

Middle ear adenoma.

Middle ear adenoma is a benign tumor of the middle ear that can have exocrine (mucinous) and/or neuroendocrine differentiation. Early authors described a separate tumor with predominantly neuroendocrine differentiation as a middle ear carcinoid tumor, but these are now known to be the same tumor. We review the literature of this tumor, including the clinical presentation, gross pathology, histopathology, immunohistochemistry, differential diagnosis, and prognosis.

Review of pineal anlage tumor with divergent histology.

Pineal anlage tumor is an extremely rare tumor that is not listed in the 2000 World Health Organization Classification of nervous system tumors. It has been defined as a primary pineal tumor with both neuroepithelial and ectomesenchymal differentiation and without endodermal differentiation. We review the literature on this tumor, including the clinical presentation, gross pathology, histopathology, immunohistochemistry, differential diagnosis, and prognosis.

Relative frequencies of Alzheimer disease, Lewy body, vascular and frontotemporal dementia, and hippocampal sclerosis in the State of Florida Brain Bank.

Alzheimer disease (AD) is the most common dementing illness in the elderly, but there is equivocal evidence regarding the frequency of other disorders such as Lewy body disease (LBD), vascular dementia (VaD), frontotemporal dementia (FTD), and hippocampal sclerosis (HS). This ambiguity may be related to factors such as the age and gender of subjects with dementia. Therefore, the objective of this study was to calculate the relative frequencies of AD, LBD, VaD, FTD, and HS among 382 subjects with dementia from the State of Florida Brain Bank and to study the effect of age and gender on these frequencies. AD was the most frequent pathologic finding (77%), followed by LBD (26%), VaD (18%), HS (13%), and FTD (5%). Mixed pathology was common: Concomitant AD was present in 66% of LBD patients, 77% of VaD patients, and 66% of HS patients. The relative frequency of VaD increased with age, whereas the relative frequencies of FTD and LBD declined with age. Males were overrepresented among those with LBD, whereas females were overrepresented among AD subjects with onset age over 70 years. These estimates of the a priori probabilities of dementing disorders have implications for clinicians and researchers.

Neurofilament inclusion body disease: a new proteinopathy?

We describe four cases of a new clinicopathological entity presenting with either a frontotemporal dementia or corticobasal degeneration syndrome with a mean age of onset of 45 years (range 41-50) characterized pathologically by deposition of neurofilament proteins. All four patients had a rapidly progressive course and have become mute and non-ambulatory, and three have died after mean illness duration of only 3 years (range 2 1/2 -4). Both structural (MRI) and functional (PET and SPECT) imaging demonstrated frontal and temporal lobe and basal ganglia involvement. Gross neuropathological examination in the three deceased patients (the fourth patient, still alive, was diagnosed by brain biopsy) revealed changes affecting predominantly the frontal and temporal cortices, basal ganglia and brainstem. There was superficial linear spongiosis affecting the frontal lobes in all three autopsied patients, and severe caudate atrophy was noted in two of them and demonstrated on MRI in the living patient. On routine staining, there were numerous intracytoplasmic inclusions, which ranged from eosinophilic to basophilic. Some had a clearly defined basophilic margin, while others were granular with a hyaline core. With modified Bielschowsky silver technique, a small number of the inclusions were intensely stained. Inclusions were not labelled with other silver stains. Immuno histochemistry revealed that the inclusions were immunoreactive with antibodies to neurofilament heavy and light chain subunits and to ubiquitin, but not with antibodies to tau and alpha-synuclein. These neurofilament- and ubiquitin-positive inclusions were widespread, specific to neurons and occasionally intranuclear. The frequency and distribution of the inclusions and the silver and immunohistochemical profiles in these four cases is novel and has not been described in detail before. We propose the term neurofilament inclusion body disease for this entity.