Multivariate analysis of 3D ToF-SIMS images: method validation and application to cultured neuronal networks.

Advanced data analysis tools are crucial for the application of ToF-SIMS analysis to biological samples. Here, we demonstrate that by using a training set approach principal components analysis (PCA) can be performed on large 3D ToF-SIMS images of neuronal cell cultures. The method readily provides access to sample component information and significantly improves the images' signal-to-noise ratio (SNR).

Acute spinal cord compression by subarachnoid and subdural hematoma occurring in association with brachial plexus avulsion. Case report.

The authors report a case of acute spinal cord compression caused by a subarachnoid and subdural hematoma. This occurred following traumatic brachial plexus avulsion. It is believed to be the first such case recorded.

Spontaneous carotid-cavernous fistula and multiple arterial dissections in type IV Ehlers-Danlos syndrome. Case report.

A 43-year-old woman without phenotypic expression of Ehlers-Danlos syndrome developed a spontaneous unilateral carotid-cavernous fistula (CCF). Attempts at balloon occlusion of the CCF were unsuccessful, and caused multiple arterial dissections and lacerations eventually leading to massive retroperitoneal hemorrhage and death. The CCF was demonstrated during postmortem studies. In addition, the patient had independent dissections of the internal carotid artery at the site of the fistula and an intracavernous aneurysm of the contralateral internal carotid artery. Despite widespread dissections, the major arteries showed only mild histological abnormalities. Morphometric analysis of collagen from the aorta revealed an increase in large-sized fibers, consistent with deficiency of Type III collagen.

Intraarterial mitomycin-C for recurrent brain metastases.

Fifteen consenting patients with brain metastases recurrent after cranial irradiation were treated with intraarterial mitomycin-C, 15 mg/m2, administered in a total final volume of 100 ml 0.45% saline over 20 min through a transfemoral catheter with a 0.2-mu in-line filter. There were 2 early deaths (one probably drug-related). Of the 13 evaluable patients, 6 (46%) responded, with both computed tomography (CT) scan and neurological improvement. Median response duration was 25 weeks, and median survival of all 15 patients was 17 weeks. Neurological, ocular, and local skin toxicity were dose-limiting. The degree of toxicity was comparable to that we have noted with other intracarotid regimens, and it appears to be less toxic when infused into the vertebral artery than are most other drugs (although experience is still limited and caution still needs to be exercised). We do not recommend that this replace or be added to cranial irradiation as front-line treatment of brain metastases, but we feel that it is an effective and reasonably well-tolerated regimen for treatment of brain metastases that have recurred after cranial irradiation. We are currently initiating studies of intraarterial mitomycin-C combined with intraarterial cisplatin and teniposide (VM-26) as treatment for recurrent brain metastases.

Hypopituitarism resulting from an intrasellar carotid aneurysm.

We report a 74 year old lady who presented with an exceedingly rare combination of an internal carotid artery aneurysm which was almost entirely intrasellar and associated with hypopituitarism but no neurological deficits. Such a lesion could be misdiagnosed as a pituitary tumour with serious consequences, if surgery is attempted without prior carotid angiography.

Spinal epidural infection.

Thirty cases of spinal epidural abscess are reviewed with particular emphasis on mode of presentation and results of treatment. In spite of repeated exhortations in the literature for earlier diagnosis, the results remain unsatisfactory because many patients have progressed to severe or complete paralysis before the correct diagnosis is made and surgical treatment carried out.

Metrizamide CT scanning in spinal nerve root cysts.

Two cases of lumbosacral root cysts of different etiology are reported. Their specific radiographic features are described using the combined technique of metrizamide myelography followed by computerized tomography of the spine. The terminology of intraspinal cysts is reviewed and their distinguishing features discussed.

Interhemispheric subdural hematoma.

Although relatively uncommon, interhemispheric subdural hematoma (ISDH) occurs more frequently than was suspected before the advent of computerized tomographic (CT) scanning. When its mass is sufficiently large to compress the medial cerebral hemisphere, specific focal neurological abnormalities may occur. These include weakness of the contralateral leg, or contralateral hemiparesis with the leg being weaker than the arm. On the unenhanced CT scan ISDH is seen as a crescent shaped, midline hyperdensity. Treatment is dictated by the clinical course. Evacuation of the hematoma by parasagittal craniotomy is recommended if the symptoms are pronounced.

Adult diastematomyelia.

With modern imaging techniques, various types of spinal dysraphism are being diagnosed in adults with increasing frequency. We report a 42-year-old woman with diastematomyelia whose symptoms characteristically were precipitated by trauma. She exhibited other typical features such as a posterior midline hair patch and vertebral malformations. Metrizamide myelography with computerized tomography showed a bony septum at T11 with a cleft at T9-T11 separating two dural tubes each of which contained a single spinal hemicord. The septum was excised with complete relief of symptoms.

Spinal epidural lipomatosis: a complication of glucocorticoid therapy.

A 21-year-old woman receiving prolonged high dosage glucocorticoids developed spinal cord compression due to excessive accumulation of epidural fat. Computerized tomographic scanning confirmed the diagnosis and revealed a peculiar pattern of spinal cord displacement which we believe to be unique to compression by fat. Laminectomy did not afford relief, possibly because of prolonged neural compression or because of compression at a higher spinal level. Although an unusual complication of Cushing's syndrome, epidural lipomatosis should be considered when such a patient develops symptoms of spinal cord or cauda equina compression.

Epidural hematoma: report of seven cases with delayed evolution of symptoms.

Epidural hematomas occasionally have a prolonged clinical course with gradual evolution of the neurologic symptoms. Seven such cases are reviewed in this report. Although the clinical course is insidious, there are certain features which should signal the presence of a slowly expanding hematoma. After an apparently minor head injury, the patient who is usually in the younger age group, develops headache. This persists and is accompanied by other non-specific neurologic symptoms which may lead to a mistaken diagnosis of "post-concussion syndrome". Papilledema and focal neurologic deficits eventually appear. Definitive diagnosis is made by the CT scan, although contrast enhancement may be necessary to confirm the nature of the lesion. The treatment is craniotomy and evacuation of the hematoma before serious neurologic deterioration occurs.

Intraspinal cysts: a classification and literature review.

Advances in radiologic technology have allowed the identification of a variety of cystic lesions of spinal nerve roots. Failure to appreciate the different characteristics of these cysts has led to a confusion in terminology, with different terms often being used to describe the same lesion. In an attempt at clarification, the literature is reviewed and a simplified classification of spinal cysts presented. The distinguishing features of each type of cyst, its investigation, and appropriate treatment are discussed.

Pyogenic psoas abscess secondary to infection of the lumbar disc space.

Two cases of staphylococcol psoas abscess are reported. These occurred many years after operations on lumbar discs, complicated by post-operative disc space infection. Clinical and radiological findings are reported. The features of psoas abscess and the management are discussed.

Spinal subdural hematoma. A review.

Fifty-eight cases of spinal subdural hematoma were obtained from a review of the literature. Of these, 50 that were reported in detail are analyzed. The data corroborate the opinion that early diagnosis and treatment result in a better prognosis.

Familial intracranial gliomas.

The pedigree of two interrelated families with 10 affected members suffering from malignant supratentorial gliomas is reported. In addition, three other unrelated families with two members each who were treated for different types of brain tumors are described. Genetic implications are discussed.

Implementing conventional logic unconventionally: photochromic molecular populations as registers and logic gates.

In this paper we detail experimental methods to implement registers, logic gates and logic circuits using populations of photochromic molecules exposed to sequences of light pulses. Photochromic molecules are molecules with two or more stable states that can be switched reversibly between states by illuminating with appropriate wavelengths of radiation. Registers are implemented by using the concentration of molecules in each state in a given sample to represent an integer value. The register's value can then be read using the intensity of a fluorescence signal from the sample. Logic gates have been implemented using a register with inputs in the form of light pulses to implement 1-input/1-output and 2-input/1-output logic gates. A proof of concept logic circuit is also demonstrated; coupled with the software workflow describe the transition from a circuit design to the corresponding sequence of light pulses.

Relationship between intracranial pressure monitoring and outcomes in severe traumatic brain injury patients.

Intracranial pressure (ICP) monitoring is recommended in patients with a severe traumatic brain injury (TBI) and an abnormal computed tomography (CT) scan. However, there is contradicting evidence about whether ICP monitoring improves outcome. The purpose of this study was to examine the relationship between ICP monitoring and outcomes in patients with severe TBI. From February 2001 to December 2008, a total of 477 consecutive adult (> or =18 years) patients with severe TBI were included retrospectively in the study. Patients who underwent ICP monitoring (n=52) were compared with those who did not (n=425). The primary outcome was hospital mortality. Secondary outcomes were ICU mortality, mechanical ventilation duration, the need for tracheostomy, and ICU and hospital length of stay (LOS). After adjustment for multiple potential confounding factors, ICP monitoring was not associated with significant difference in hospital or ICU mortality (odds ratio [OR] = 1.71, 95% confidence interval [CI] = 0.79 to 3.70, P = 0.17; OR = 1.01, 95% CI = 0.41 to 2.45, P = 0.99, respectively). ICP monitoring was associated with a significant increase in mechanical ventilation duration (coefficient = 5.66, 95% CI = 3.45 to 7.88, P < 0.0001), need for tracheostomy (OR = 2.02, 95% CI = 1.02 to 4.03, P = 0.04), and ICU LOS (coefficient = 5.62, 95% CI = 3.27 to 7.98, P < 0.0001), with no significant difference in hospital LOS (coefficient = 8.32, 95% CI = -82.6 to 99.25, P = 0.86). Stratified by the Glasgow Coma Scale score, ICP monitoring was associated with a significant increase in hospital mortality in the group of patients with Glasgow Coma Scale 7 to 8 (adjusted OR = 12.89, 95% CI = 3.14 to 52.95, P = 0.0004). In patients with severe TBI, ICP monitoring was not associated with reduced hospital mortality, however with a significant increase in mechanical ventilation duration, need for tracheostomy, and ICU LOS.