bluuebunny/crossref_metadata_2025 huggingface dataset:
Congenital infiltrating lipomatosis of the face and neck
Authors: Malik A. , Jagmohan P. , Thukral B. B. , Khanna G. , Rajni
Published: August 2004

Congenital infiltrating lipomatosis is a rare clinicopathologic entity characterized by infiltrating lipomatous tumors which, although of benign nature, have a tendency to recur after surgery. This has a predilection for the extremities and the trunk and is seen as overgrowth of soft tissue and bone. It rarely affects the face and neck. We describe two cases of congenital infiltrating lipomatosis of face and neck depicting the bone and soft tissue changes seen on computed tomography, along with a review of the literature on the subject.
Diffusion magnetic resonance imaging patterns in metabolic and toxic brain disorders
Authors: Sener R. N.
Published: August 2004

Purpose: To evaluate metabolic and toxic brain disorders that manifest with restricted, elevated, or both restricted and elevated diffusion patterns on diffusion magnetic resonance imaging (MRI).

Material and Methods: Echo‐planar diffusion MRI examinations were obtained in 34 pediatric patients with metabolic and toxic brain disorders proved by appropriate laboratory studies. The MRI unit operated at 1.5T with a gradient strength of 30 mT/meter, and a rise time of 600 μs. b=1000 s/mm2 images and apparent diffusion coefficient (ADC) maps with ADC values were studied.

Results: Three patterns were observed: 1. A restricted diffusion pattern (high signal on b=1000 s/mm2 images and low ADC values); 2. an elevated diffusion pattern (normal signal on b=1000 s/mm2 images and high ADC values); and 3. a mixed pattern (coexistent restricted and increased diffusion patterns in the same patient). Disorders manifesting with a restricted diffusion pattern included metachromatic leukodystrophy ( n=2), phenylketonuria ( n=3), maple syrup urine disease (intermediate form) ( n=1), infantile neuroaxonal dystrophy ( n=1), Leigh ( n=2), Wilson ( n=3), and Canavan disease ( n=1). Disorders with an elevated diffusion pattern included phenylketonuria ( n=1), adrenoleukodystrophy ( n=1), merosin‐deficient congenital muscular dystrophy ( n=2), mucopolysaccharidosis ( n=2), Lowe syndrome ( n=1), Leigh ( n=2), Alexander ( n=1), Pelizaeus‐Merzbacher ( n=1), and Wilson ( n=3) disease. Disorders with a mixed pattern included L‐2 hydroxyglutaric aciduria ( n=2), non‐ketotic hyperglycinemia ( n=1), infantile neuroaxonal dystrophy ( n=2), maple syrup urine disease ( n=1), and Leigh ( n=1) disease.

Conclusion: The findings suggested that the three different diffusion patterns reflect the histopathological changes associated with the disorders and different stages of a particular disorder. It is likely that the restricted diffusion pattern corresponds to abnormalities related to myelin, and the elevated diffusion pattern to disintegration of the tissue. The mixed pattern has contributions from both myelin abnormalities related to myelin disintegration of the tissue.
Multi‐slice computed tomography angiography in the detection of residual or recurrent cerebral aneurysms after surgical clipping
Authors: Teksam M. , McKinney A. , Cakir B. , Truwit C. L.
Published: August 2004

Purpose: To assess the diagnostic accuracy of multi‐slice computed tomography (MSCT) angiography compared to digital subtraction angiography (DSA) in detecting residual or recurrent aneurysms in patients undergoing aneurysm clipping surgery.

Material and Methods: Eight patients with nine aneurysms who had both MSCTA and DSA were included in the study. Two independent experienced neuroradiologists evaluated the examinations.

Results: Accuracy, sensitivity, and specificity of detecting residual or recurrent aneurysms on MSCTA were 0.80, 0.60, and 1.00, respectively. Positive and negative predictive values were 1.00 and 0.71, respectively.

Conclusion: MSCTA is a promising technique for evaluating residual or recurrent aneurysms in patients undergoing surgical treatment of aneurysm with titanium clips.
Validation of diagnostic imaging based on repeat examinations. an image interpretation model
Authors: Isberg B. , Thorstensen Ö. , Jorulf H.
Published: August 2004

Purpose: To develop an interpretation model, based on repeatedly acquired images, aimed at improving assessments of technical efficacy and diagnostic accuracy in the detection of small lesions.

Material and Methods: A theoretical model is proposed. The studied population consists of subjects that develop focal lesions which increase in size in organs of interest during the study period. The imaging modality produces images that can be re‐interpreted with high precision, e.g. conventional radiography, computed tomography, and magnetic resonance imaging. At least four repeat examinations are carried out.

Results: The interpretation is performed in four or five steps: 1. Independent readers interpret the examinations chronologically without access to previous or subsequent films. 2. Lesions found on images at the last examination are included in the analysis, with interpretation in consensus. 3. By concurrent back‐reading in consensus, the lesions are identified on previous images until they are so small that even in retrospect they are undetectable. The earliest examination at which included lesions appear is recorded, and the lesions are verified by their growth (imaging reference standard). Lesion size and other characteristics may be recorded. 4. Records made at step 1 are corrected to those of steps 2 and 3. False positives are recorded. 5. (Optional) Lesion type is confirmed by another diagnostic test.

Conclusion: Applied on subjects with progressive disease, the proposed image interpretation model may improve assessments of technical efficacy and diagnostic accuracy in the detection of small focal lesions. The model may provide an accurate imaging reference standard as well as repeated detection rates and false‐positive rates for tested imaging modalities. However, potential review bias necessitates a strict protocol.
Detection of small implanted tumors growing during repeated magnetic resonance imaging of the rabbit liver: application of an interpretation model
Authors: Thorstensen Ö. , Isberg B. , Jorulf H. , Svahn U. , Westman L. , Venizelos N. , Nennesmo I.
Published: August 2004

Purpose: To apply experimentally and further develop a new image interpretation model based on repeated imaging and aimed at improving assessments of technical efficacy and diagnostic accuracy in the detection of small lesions.

Material and Methods: VX2 carcinoma was implanted in the liver of 14 rabbits as two 1.1–1.7 mm3 cores. Magnetic resonance imaging was performed before and 4 days after implantation and then every second day up to the 14th to 20th day. One T2‐weighted sequence (TSE T2) and three T1‐weighted sequences (SE T1, GE T1, and TFL T1) were used. Interpretation was performed stepwise: three readers independently interpreted image sequences chronologically (step 1). Tumors were included at the last examination (step 2). By concurrent interpretation of repeated examinations, the earliest day at which tumors became visible and tumor size were recorded (step 3). Records were corrected (step 4) and autopsy was performed (step 5). Two procedures for use in calculating repeated detection rates of tumors with different magnetic resonance imaging sequences are presented and discussed.

Results: Of 40 macroscopic tumors, 34 were included. They were mainly small (size range SE T1: 1–3 mm, TSE T2: 1.5–5 mm) when they became visible as determined at step 3, which was consistently earlier than observed at step 1. TSE T2, SE T1, and GE T1 did not differ significantly regarding earliest day of detection (step 3), while TFL T1 revealed the tumors later. The initial repeated detection rates were higher with TSE T2 than with the other sequences. Frequency of false positives varied over time, indicating fluctuating criteria for reporting tumors.

Conclusion: A theoretical image interpretation model previously described proved to be applicable for detection of experimental liver tumors. The model was improved by introducing calculations of repeated detection rates for initial image interpretation using an imaging reference standard.
Unusual enhancement pattern of liver lesions in hepatosplenic candidiasis
Authors: Rudolph J. , Rodenwaldt J. , Ruhnke M. , Hamm B. , Kopka L.
Published: August 2004

Purpose: To describe an unusual enhancement pattern of hepatosplenic candidiasis (HSC) liver lesions in biphasic spiral liver computed tomography (CT).

Material and Methods: Twenty‐one patients with suspected HSC were scanned with a biphasic liver CT perfusion protocol. The liver lesions detected were assessed for their morphology and enhancement pattern during both perfusion phases. A liver biopsy was performed in 11/21 patients.

Results: The majority of hepatic lesions in 15/21 patients showed the well‐known abscess‐like pattern. In 6/21 patients an uncommon central contrast enhancement with a peripheral double ring was detected in the arterial phase. In some cases the lesions showed decreased diameter or even seemed to disappear completely in the portalvenous phase.

Conclusions: CT in the arterial phase showed an unusual enhancement pattern of liver lesions in HSC. Scanning only in the portalvenous phase implies possible pitfalls, because lesions may be overlooked or undersized. Therefore, biphasic liver CT is considered essential in the diagnosis and follow‐up of HSC in clinical practice.
Combined MR examination of prostate: is it reliable?
Authors: Chabanova E. , Løgager V. , Thomsen H.
Published: August 2004

A combination of magnetic resonance (MR) methods (T2‐weighted MRI, proton MR spectroscopy, and dynamic contrast enhancement) gives the highest sensitivity and specificity for identification of prostate cancer by MRI. The prostate MR findings of a patient with a congenital cystic disease of seminal vesicle are presented. To our knowledge, this is the only case described in the literature. The MR examination resulted in a false‐positive indication of prostate cancer.
Dynamic targeting of the replication machinery to sites of DNA damage
Authors: Solomon David A. , Cardoso M. Cristina , Knudsen Erik S.
Published: August 2004

Components of the DNA replication machinery localize into discrete subnuclear foci after DNA damage, where they play requisite functions in repair processes. Here, we find that the replication factors proliferating cell nuclear antigen (PCNA) and RPAp34 dynamically exchange at these repair foci with discrete kinetics, and this behavior is distinct from kinetics during DNA replication. Posttranslational modification is hypothesized to target specific proteins for repair, and we find that accumulation and stability of PCNA at sites of damage requires monoubiquitination. Contrary to the popular notion that phosphorylation on the NH2 terminus of RPAp34 directs the protein for repair, we demonstrate that phosphorylation by DNA-dependent protein kinase enhances RPAp34 turnover at repair foci. Together, these findings support a dynamic exchange model in which multiple repair factors regulated by specific modifications have access to and rapidly turn over at sites of DNA damage.
AMSH is an endosome-associated ubiquitin isopeptidase
Authors: McCullough John , Clague Michael J. , Urbé Sylvie
Published: August 2004

The JAMM (JAB1/MPN/Mov34 metalloenzyme) motif has been proposed to provide the active site for isopeptidase activity associated with the Rpn11/POH1 subunit of the 19S-proteasome and the Csn5-subunit of the signalosome. We have looked for similar activity in associated molecule with the SH3 domain of STAM (AMSH), a JAMM domain–containing protein that associates with the SH3-domain of STAM, a protein, which regulates receptor sorting at the endosome. We demonstrate isopeptidase activity against K48-linked tetraubiquitin and K63-linked polyubiquitin chains to generate di-ubiquitin and free ubiquitin, respectively. An inactivating mutation (D348A) in AMSH leads to accumulation of ubiquitin on endosomes and the concomitant stabilization of a ubiquitinated form of STAM, which requires an intact ubiquitin interaction motif (UIM) within STAM. Short interfering RNA knockdown of AMSH enhances the degradation rate of EGF receptor (EGFR) following acute stimulation and ubiquitinated EGFR provides a substrate for AMSH in vitro. We propose that AMSH is a deubiquitinating enzyme with functions at the endosome, which oppose the ubiquitin-dependent sorting of receptors to lysosomes.
In vivo monitoring of Ca2+ uptake into mitochondria of mouse skeletal muscle during contraction
Authors: Rudolf Rüdiger , Mongillo Marco , Magalhães Paulo J. , Pozzan Tullio
Published: August 2004

Although the importance of mitochondria in patho-physiology has become increasingly evident, it remains unclear whether these organelles play a role in Ca2+ handling by skeletal muscle. This undefined situation is mainly due to technical limitations in measuring Ca2+ transients reliably during the contraction–relaxation cycle. Using two-photon microscopy and genetically expressed “cameleon” Ca2+ sensors, we developed a robust system that enables the measurement of both cytoplasmic and mitochondrial Ca2+ transients in vivo. We show here for the first time that, in vivo and under highly physiological conditions, mitochondria in mammalian skeletal muscle take up Ca2+ during contraction induced by motor nerve stimulation and rapidly release it during relaxation. The mitochondrial Ca2+ increase is delayed by a few milliseconds compared with the cytosolic Ca2+ rise and occurs both during a single twitch and upon tetanic contraction.
Dynein/dynactin regulate metaphase spindle length by targeting depolymerizing activities to spindle poles
Authors: Gaetz Jedidiah , Kapoor Tarun M.
Published: August 2004

During cell division metaphase spindles maintain constant length, whereas spindle microtubules continuously flux polewards, requiring addition of tubulin subunits at microtubule plus-ends, polewards translocation of the microtubule lattice, and removal of tubulin subunits from microtubule minus-ends near spindle poles. How these processes are coordinated is unknown. Here, we show that dynein/dynactin, a multi-subunit microtubule minus-end–directed motor complex, and NuMA, a microtubule cross-linker, regulate spindle length. Fluorescent speckle microscopy reveals that dynactin or NuMA inhibition suppresses microtubule disassembly at spindle poles without affecting polewards microtubule sliding. The observed uncoupling of these two components of flux indicates that microtubule depolymerization is not required for the microtubule transport associated with polewards flux. Inhibition of Kif2a, a KinI kinesin known to depolymerize microtubules in vitro, results in increased spindle microtubule length. We find that dynein/dynactin contribute to the targeting of Kif2a to spindle poles, suggesting a model in which dynein/dynactin regulate spindle length and coordinate flux by maintaining microtubule depolymerizing activities at spindle poles.
T cell receptor antagonism interferes with MHC clustering and integrin patterning during immunological synapse formation
Authors: Sumen Cenk , Dustin Michael L. , Davis Mark M.
Published: August 2004

T cell activation by nonself peptide–major histocompatibility complex (MHC) antigenic complexes can be blocked by particular sequence variants in a process termed T cell receptor antagonism. The inhibition mechanism is not understood, although such variants are encountered in viral infections and may aid immune evasion. Here, we study the effect of antagonist peptides on immunological synapse formation by T cells. This cellular communication process features early integrin engagement and T cell motility arrest, referred to as the “stop signal.” We find that synapses formed on membranes presenting antagonist–agonist complexes display reduced MHC density, which leads to reduced T cell proliferation that is not overcome by the costimulatory ligands CD48 and B7-1. Most T cells fail to arrest and crawl slowly with a dense ICAM-1 crescent at the leading edge. Similar aberrant patterns of LFA-1/ICAM-1 engagement in live T–B couples correlate with reduced calcium flux and IL-2 secretion. Hence, antagonist peptides selectively disable MHC clustering and the stop signal, whereas LFA-1 valency up-regulation occurs normally.
Retinosomes
Authors: Imanishi Yoshikazu , Gerke Volker , Palczewski Krzysztof
Published: August 2004

Lipid bodies form autonomous intracellular structures in many model cells and in some cells of specific tissue origin. They contain hydrophobic substances, a set of structural proteins such as perilipin or adipose differentiation-related protein, enzymes implicated in lipid metabolism, and proteins that participate in signaling and membrane trafficking. Retinosomes, particles reminiscent of lipid bodies, have been identified in retinal pigment epithelium as distinct structures compartmentalizing a metabolic intermediate involved in regeneration of the visual chromophore. These observations suggest that lipid bodies, including retinosomes, carry out specific functions that go beyond those of mere lipid storage organelles.
Transcallosal Approach to the Anterior Ventricular System
Authors: Shucart William A. , Stein Bennett M.
Published: August 2004

Using an anterior transcallosal approach, we operated upon 25 patients with lateral and 3rd ventricular lesions. The facility of this route is discussed, and the operative technique is presented.
Human Malignant Gliomas Treated with Chemotherapy
Authors: Schiffer Davide , Giordana Maria Teresa , Buoncristiani Pio , Paoletti Pietro
Published: August 2004

Twenty-one malignant cerebral tumors treated with chemotherapy after operation or clinical diagnosis were studied. The brains were cut in coronal slices that were embedded in paraffin. The histological picture of the whole tumor and of the adjacent normal tissue was carefully investigated, and it was compared with the histological features noted on biopsy. The general characteristics of glioblastoma, including wide central necrosis, were present in all of the cases. No specific alterations referable to chemotherapy were found. The increase of monstrous cells and the decrease of mitoses, although observable in some areas, were not of general importance. There was a statistical relationship between the occurrence of reactive astrocytes with bizarre nuclei and repeated chemotherapy or length of time after radiotherapy.
Pediatric Posterior Fossa Tumors
Authors: Epstein Fred , Murali Rajagopalan
Published: August 2004

Many neurosurgeons recommend a “preoperative” shunt for children with posterior fossa tumors. It has been reported that the definitive surgery is simplified and the postoperative course is more benign as a result of the cerebrospinal fluid diversion. The present report documents complications as a result of upward herniation and hemorrhage within the tumor after shunt placement. On the basis of this experience, we conclude that a shunt is potentially hazardous and should be restricted to that selected group of patients who are acutely ill from increased intracranial pressure that is refractory to temporizing pharmacological management.
Chronic Headache in the Shunt-dependent Adolescent with Nearly Normal Ventricular Volume
Authors: Epstein Fred , Marlin Arthur E. , Wald Alvin
Published: August 2004

The shunt-dependent adolescent will occasionally manifest shunt malfunction by intermittent or chronic headache without any obvious signs of increased intracranial pressure (ICP). A small percentage of these patients will have nearly normal ventricular volume, making the diagnosis and treatment difficult. The authors present a comprehensive approach to this problem that uses computerized axial tomography (CT), ICP monitoring, positive contrast or isotope shunt scan, shunt revision, subtemporal craniectomy, or medical management as the individual situation dictates. The CT scan identifies patients with nearly normal ventricular volume. ICP monitoring then determines whether there is shunt malfunction. The shunt scan aids in localization of the malfunction. For distal obstruction, a simple revision is performed. When proximal shunt malfunction occurs, either subtemporal craniectomy or revision is carried out. It has been documented that occasionally ICP is episodically increased in the absence of shunt malfunction. This is secondary to abnormal brain compliance, and subtemporal craniectomy alone or in conjunction with corticosteroids is curative. This comprehensive approach is designed to provide a method for recognizing and treating intermittently increased ICP in the shunt-dependent child.
Treatment of Patients with Neurological Deficits Associated with Cerebral Vasospasm by Intravascular Volume Expansion
Authors: Pritz Michael B. , Giannotta Steven L. , Kindt Glenn W. , McGillicuddy John E. , Prager Richard L.
Published: August 2004

Four patients, including one preoperative patient, developed neurological deficits associated with angiographically proven cerebral vasospasm and were treated with intravascular volume expansion. Indicator dilution techniques were employed to monitor intravascular volume and cardiac functions during treatment. All four patients improved promptly. None of the patients developed cardiac or pulmonary dysfunction despite marked increase in intravascular volume and despite several risk factors such as cardiac symptoms, electrocardiographic abnormalities, and advanced age. The techniques of monitoring and controlling intravascular volume are described. We believe that this is an important therapeutic adjunct for certain aneurysm patients.
Colonic Ileus Complicating Laminectomy
Authors: Haimovic Itzhak C. , Arbit Ehud , Posner Jerome B.
Published: August 2004

Colonic ileus is an unusual form of adynamic ileus that often mimics true intestinal obstruction and that, if not recognized and adequately treated, may be fatal. We have encountered three patients in whom this syndrome followed apparently uncomplicated laminectomy for herniated disc or spinal stenosis. Two of our three patients required abdominal exploration for diagnosis and treatment of the complication. At operation, a large distended colon without volvulus or tumor was found. Cecostomy was performed in both patients. The third patient was treated conservatively. All three patients recovered without sequelae. The pathogenesis of the illness is unknown, but the most widely held view is that ileus results from increased sympathetic activity that inhibits the bowel. Conservative management consisting of correction of any fluid or electrolyte abnormalities, continuous gastric suction via nasogastric tube, and placement of a rectal tube may relieve the symptoms. Patients should, however, be followed carefully and, if distention of the cecum exceeds 12 cm, a decompressive operation is indicated.
Evaluation of Dorsal Column Stimulation in the Treatment of Chronic Pain
Authors: Young Ronald F.
Published: August 2004

Dorsal column stimulation (DCS) was used in the treatment of chronic intractable pain in 51 patients. Twenty-five of the patients had back and leg pain secondary to the treatment of intervertebral disc disease; 11 had postoperative pain after general or thoracic surgical procedures. The remainder suffered pain related to multiple sclerosis, spinal cord injury, carcinoma, and peripheral vascular disease. Pain had been present for a mean of 24 months. Thirty-seven patients underwent DCS electrode placement by open laminectomy, and 11 had percutaneous epidural DCS electrode placement. Three patients first underwent epidural DCS electrode implantation and subsequently had DCS electrode implantation by laminectomy. No major complications were noted, although multiple lesser complications required 33 additional operative procedures for correction. Follow-up periods ranged from 12 to 67 months, with a mean of 38 months. Immediately after implantation. 47% of the patients reported that they had essentially complete pain relief, but 3 years later this had decreased to 8%. No patient followed for 4 years or longer reported complete pain relief. Thirty-three per cent of the patients discontinued the regular use of narcotics for pain relief after DCS electrode implantation. Unfortunately, only 16% were able to return to gainful employment or full physical activity after DCS. Based on these data and a review of the literature, the following conclusions are made: (a) assessment of success in the treatment of chronic pain is strongly dependent on the criteria used for patient evaluation: (b) with the criteria of this report, DCS is a relatively ineffective treatment for chronic pain; (c) epidural percutaneous DCS systems are no more effective than are those placed by laminectomy, and, because of technical problems with epidural systems (mainly lead breakage and migration), the latter may actually be less effective; and (d) at present DCS seems to play a minor role in the treatment of chronic intractable pain.
An Automated Tumor Resection Device for Neurological Surgery
Authors: Lazar Martin L. , Wang Carl , Bland James E.
Published: August 2004

A pneumatically activated cutting probe has been designed for the neurosurgical removal of nervous system tumors or diseased tissue. The hand-held probe is formed of concentric slender tubes, one reciprocating inside the other. A scalpelsharp edge on the tip of the inner tube moves in a shear motion past a stationary port on one side near the distal end of the outer tube. The reciprocating motion of the inner tube is provided by a pneumatic power source housed in a separate control console.
Technical Considerations for Facilitation of Selective Percutaneous Radiofrequency Neurolysis of the Trigeminal Nerve
Authors: Apfelbaum Ronald I.
Published: August 2004

Fine points of the technique of selective percutaneous radiofrequency trigeminal neurolysis relative to patient preparation. accurate and rapid foramen ovale puncture, electrode positioning, and neurolytic lesions are discussed. These measures. which have evolved from our experience in treating trigeminal neuralgia by this method over the last 4 years, have made the procedure safer and less painful but also significantly more expedient.
Spinal Subarachnoid Hematoma after Lumbar Puncture Producing Acute Thoracic Myelopathy
Authors: Diaz Fernando G. , Yock Douglas H. , Rockswold Gaylan L.
Published: August 2004

A case of subarachnoid hematoma after a difficult lumbar puncture and anticoagulation is presented. Subarachnoid adhesions preventing the free flow of spinal fluid at the T-6 level served to limit the cranial progression of the hemorrhage and produced a transverse myelopathy at that level. The underlying pathology, clinical course, and myelographic findings are reviewed. Pertinent literature is presented.
Endodermal Sinus Tumor of the Pineal Region
Authors: Lee Sang H. , Sundaresan Narayan , Berta Jereb , Galicich Joseph H.
Published: August 2004

A 13-year-old boy presented with symptoms and signs of a posterior 3rd ventricle tumor associated with raised levels of serum and cerebrospinal alpha-fetoprotein. The patient underwent subtotal resection of the tumor followed by craniospinal radiation. Histopathological examination revealed a pure endodermal sinus tumor. Endodermal sinus tumors represent a rare type of germ cell tumor, only 13 intracranial cases having been reported in the literature.
Syndrome of Inappropriate Antidiuretic Hormone Secretion after Spontaneous Subarachnoid Hemorrhage
Authors: Wise Burton L.
Published: August 2004

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) developed approximately 7 days after a spontaneous subarachnoid hemorrhage in a 63-year-old woman with an anterior cerebral artery aneurysm. The hyponatremia associated with this syndrome resulted in a deterioration of the patient's clinical condition and focal neurological signs, which simulated the clinical deterioration after spontaneous subarachnoid hemorrhage that is often caused by other intracranial pathological conditions. The focal neurological signs in particular are likely to be interpreted as indicating one of these other conditions. Prompt recognition and treatment of the SIADH resulted in prompt improvement, and we were then able to proceed with the planned craniotomy for the aneurysm. The syndrome and its importance are discussed.
Intracranial Clips: An Examination of the Devices Used for Aneurysm Surgery
Authors: Manuel Dujovny , Nir Kossovsky , Ram Kossowsky , Alfred Perlin , Ricardo Segal , Fernando G. Diaz , James I. Ausman
Published: August 2004

A properly functioning aneurysm clip is of paramount importance in the surgical ablation of intracranial aneurysms. An appropriate match between the closing force needed to ablate an aneurysm and the force exerted by the aneurysm clip must be achieved. In this study, the opening and closing forces exerted by several commonly used aneurysm clips were tested. There was a strong correlation between the classification of the clips, according to the Dujovny system, and their mechanical behavior. Minimal variability among different lots of the same clip type and minimal hysteresis were generally exhibited by the alpha mobile fulcrum class clips, such as the Yasargil, Vari-Angle McFadden, Scoville, and Mayfield clips. Significant exceptions included several types of Mayfield and Drake clips. In contrast, pivot class clips generally showed twice as much lot variability among different lots, as well as a significant amount of hysteresis. Clips of this class include the Vari-Angle, Heifetz, and Pivot clips. Because significant variations in clip force exist and because several other factors can compound these differences, it is suggested that aneurysm clips be individually tested for their closing forces before they are used in an operation.
Tentorial Meningiomas: Surgical Management and Results
Authors: Laligam N. Sekhar , Peter J. Jannetta , Joseph C. Maroon
Published: August 2004

We report the clinical features, radiological studies, operative management, and follow-up data in a series of 27 patients with tentorial meningiomas. Headache and extremity or gait ataxia were the most common presenting symptoms. Signs of elevated intracranial pressure and cranial nerve, pyramidal, or cerebellar deficits were the most common findings on neurological examination. Computed tomography was the single most important diagnostic tool. Cerebral arteriography was considered important to define arterial and venous relationships to the tumor. Two patients in the series underwent cerebrospinal fluid shunting only. The others underwent an operation on the tumor, with or without a shunt. There were 2 postoperative deaths early in the series, 1 due to cerebellar swelling and the other due to brain stem infarction. With an average follow-up of 5.5 years, 19 patients are independent and have resumed their premorbid level of activity. The pathological anatomy of these lesions is described. The different operative approaches to this tumor are discussed.
Cerebral Edema Associated with Meningiomas: Possible Role of a Secretory-Excretory Phenomenon
Authors: Jacques Philippon , Jean Francois Foncin , Raoul Grob , Abbas Srour , Michel Poisson , Bertrand F. Pertuiset
Published: August 2004

A retrospective study of cerebral edema in 40 patients with intracranial meningiomas seems to demonstrate that the extent of edema is not related to anatomical factors such as location. Histological type is more significant; cerebral edema is usually observed with meningothelial forms. Furthermore, the study of tumor cells by electron microscopic methods indicates that secretory-excretory activity is closely associated with the production of peritumoral edema. The ultrastructural aspects of this secreted material are described, but further biochemical studies are necessary to determine its exact nature. The possible role of tumoral steroid receptors in the secretory-excretory phenomenon is discussed.
Neurological Improvement Associated with Late Decompression of the Thoracolumbar Spinal Cord
Authors: Dennis J. Maiman , Sanford J. Larson , Edward C. Benzel
Published: August 2004

We reviewed the cases of 20 patients admitted to our institution with thoracolumbar spinal cord injury who had previously undergone laminectomy and/or spinal instrumentation. Thirteen patients had a mass in the spinal canal, and 7 had kyphotic deformities. The lateral extracavitary approach to the spine and posterior stabilization when indicated were done in each. Seventeen patients obtained substantial neurological improvement. All 7 patients with kyphosis regained the ability to walk, as did all but 3 of the nonambulatory patients with a mass in the spinal canal. Morbidity was limited to pneumothorax and 1 case of late kyphosis associated with premature removal of the spinal fixation devices. Elective anterior approaches for reconstruction of the spinal canal with appropriate stabilization afford the best opportunity for neurological improvement in cases of thoracolumbar spinal cord injury.
Posterior Stabilization with an Interlaminar Clamp in Cervical Injuries: Technical Note and Review of the Long Term Experience with the Method
Authors: Renn O. Holness , William S. Huestis , William J. Howes , Roland A. Langille
Published: August 2004

An alternative method of cervical fixation utilizing a stainless steel clamp is described. The clamp is applied to the adjoining laminae of involved vertebrae in those cervical dislocations and subluxations with posterior instability. The long term results of this method have been most satisfactory, as indicated by our follow-up of 51 patients treated during the last decade.
Asymptomatic Leptomeningeal Dissemination of Tumor to the Spinal Cord: Report of Three Cases
Authors: Tadanori Tomita
Published: August 2004

Three children with a history of malignant tumor (cerebellar medulloblastoma in two cases and adrenal neuroblastoma in one case) are discussed. All three had diffuse leptomeningeal dissemination, which was confirmed at autopsy. Computed tomography (CT) revealed diffuse enhancement of the intracranial subarachnoid spaces after the administration of contrast material. Despite the absence of spinal cord signs and symptoms, autopsy showed severe diffuse seeding of neoplastic cells in the spinal subarachnoid space giving the spinal cord the appearance of a “bamboo stick.” Myelography is necessary to disclose clinically silent spinal cord lesions when CT or cerebrospinal fluid cytological examination reveals evidence of subarachnoid dissemination of tumor.
Spasmodic Torticollis as a Cause of Ulnar Nerve Entrapment
Authors: Saul I. Weingarden , Harold P. Weingarden
Published: August 2004

Spasmodic torticollis is thought to be a central nervous system disorder with no peripheral nervous system component. Several consecutive patients with spastic torticollis were found to have ulnar nerve compromise at the elbow on the side ipsilateral to the direction of chin turning. This article describes three such patients in detail. It is postulated that the cause is the stereotypical posture assumed by these patients in using their hand to maintain a neutral head position. The chronic leaning and elbow flexion place the ulnar nerve at risk for the development of pressure neuropathy.
Contralateral Trigeminal Nerve Dysfunction as a False Localizing Sign in Acoustic Neuroma: A Clinical and Electrophysiological Study
Authors: Matthew Koenig , Krishna Kalyan-Raman , Om N. Sureka
Published: August 2004

A 49-year-old woman presented with right facial sensory impairment due to trigeminal nerve dysfunction caused by a contralateral acoustic neuroma. The mechanism of the falsely localizing trigeminal involvement is probably displacement and distortion of the brain stem by the large mass lesion and not increased intracranial pressure. A preoperative orbicularis oculi reflex study was abnormal and indicative of right trigeminal nerve dysfunction; after surgical removal of the tumor, the orbicularis oculi reflex study was normal. We conclude that a false localizing sign of trigeminal nerve dysfunction can occur rarely on the contralateral side in patients with large posterior fossa tumors, especially tumors arising from the cerebellopontine angle, and should be considered in the differential diagnosis of hemifacial sensory disturbance.
Microvascular Decompression of the Eighth Cranial Nerve for Disabling Tinnitus without Vertigo: A Case Report
Authors: Tadashi Kudo , Kenjiro Ito
Published: August 2004

We report a patient with disabling tinnitus that responded dramatically to microvascular decompression of the 8th cranial nerve. The most annoying, episodic, high pitched tinnitus disappeared immediately after the operation. Two types of constant tinnitus either persisted or recurred after the procedure. Nevertheless, the remaining tinnitus is much reduced compared to the preoperative level. The patient was able to return to his previous work 2 months after operation.
Use of Trapezius Muscle for Closure of Complicated Upper Spinal Defects
Authors: Alan E. Seyfer , Allen S. Joseph
Published: August 2004

Dehiscence of cervicothoracic incisional wounds is an occasional complication of laminectomy. Subsequent healing can be further compromised by associated immunodeficiency, malignancy, infection, previous radiotherapy, and cerebrospinal fluid fistula. Two such cases that responded dramatically to the use of a lower trapezius muscle flap are described. Pertinent anatomical and surgical considerations are reviewed.
Computed Tomographic Discography in the Evaluation of Extreme Lateral Disc Herniation
Authors: Edgardo J. C. Angtuaco , John C. Holder , Warren C. Boop , Eugene F. Binet
Published: August 2004

Thin section, high resolution computed tomographic (CT) scans of the lumbar spine produce images that can show herniated intervertebral discs without intravenous or intrathecal contrast enhancement. With this technique, the diagnosis of posterolateral and midline herniation has been greatly facilitated. This communication reports the use of CT discography in the preoperative evaluation of two patients who were shown at discography and proven at operation to have extreme lateral disc herniations.
Multiple Meningiomas of the Cervical Spinal Cord Associated with Klippel-Feil Malformation and Atlantooccipital Assimilation
Authors: Peter O. Holliday , Courtland Davis , Jean Angelo
Published: August 2004

A case of multiple meningiomas confined solely to the cervical spinal canal in association with multiple bony abnormalities of the cervical spine is presented. The relationship of this entity to neurofibromatosis, whether the central type or a form fruste, is explored. It is suggested that multiple meningiomas unassociated with other central or peripheral tumors may present a distinct clinical entity and may occur in an as yet uncharacterized familial pattern.
Pituitary Apoplexy: A Review
Authors: Erico Ramos Cardoso , Eric Weston Peterson
Published: August 2004

The authors present a critical review of the literature on the hemorrhagic complications of pituitary adenomas, especially those leading to apoplexy. They emphasize the distinction between pituitary apoplexy, hemorrhages leading to sudden endocrine alterations, and asymptomatic hemorrhages. Moreover, they speculate upon the possible pathophysiology of pituitary apoplexy and its predisposing factors. The clinical presentation, natural history, radiological findings, and differential diagnosis are also discussed. Finally, the historical evolution of the treatment of pituitary apoplexy is reviewed, with emphasis on the surgical treatment.
Electrothrombosis of Spontaneous Carotid-Cavernous Fistula by Copper Needle Insertion
Authors: Michiharu Nishijima , Kazuyo Kamiyama , Nobuo Oka , Shunro Endo , Akira Takaku
Published: August 2004

Electrothrombosis by copper needle insertion was used to treat three cases of spontaneous carotid-cavernous fistula. These patients had been treated conservatively for 6 months or more, but their symptoms had not improved. Angiography showed that the feeding arteries were branches of both the ipsilateral internal and the ipsilateral external carotid artery. Frontotemporal craniotomy was performed, and copper needles were inserted transdurally into the cavernous sinus. Closure of the fistula was verified by intraoperative angiography in all cases, and the symptoms improved after the operation. However, one patient had postoperative transient 3rd nerve palsy. Another had Gerstmann's syndrome due to narrowing of the internal carotid artery by a needle and worsening of the preoperative 6th nerve palsy. In one case, the operation was uneventful. Based on our experience, we discuss several problems with this technique.
Evoked Potential Correlates of Recovery from Aphasia after Focal Left Hemisphere Injury in Adults
Authors: Andrew C. Papanicolaou , Harvey S. Levin , Howard M. Eisenberg
Published: August 2004

An evoked potentials (EPs) paradigm that has been effective in demonstrating asymmetries in hemispheric activation during cognitive tasks was used to assess cerebral reorganization for language in recovered aphasics. Cortical click EPs were recorded bilaterally in normal volunteers, recovered aphasics who had sustained focal left hemisphere injury, and nonaphasic patients with diffuse injuries during a control condition of attending only to the click and during a verbal memory task. During that task, EP amplitude attenuation occurred in the left hemisphere for the normal subjects and the nonaphasic patients and in the right hemisphere for the recovered aphasics. These contrasting asymmetries in hemispheric activation suggest that a shift of hemispheric specialization for verbal processing contributes to the recovery of linguistic competence in adult aphasics.
Can Neuropsychological Tests Detect the Sites of Cerebrovascular Stenoses and Occlusions?
Authors: Anne Dull Baird , Kenneth M. Adams , Mark W. Shatz , Gregory G. Brown , Fernando Diaz , James I. Ausman
Published: August 2004

Conventional neuropsychological data may not mirror the site of cerebrovascular stenosis in a patient with mild to moderate symptoms. In this study, three groups of cerebral revascularization candidates failed to differ on an extended Halstead-Reitan battery: patients with symptoms and angiographic results referable to the carotid arterial system, subjects with clinical signs and neuroradiological findings referable to the vertebrobasilar arterial system, and patients with symptoms of cerebral ischemia but negative angiograms. Consistent with previous work, these patients generally were mildly impaired on neuropsychological tests, even though many were not symptomatic at the time of assessment. Neuropsychological tests seem to be sensitive to the presence and severity of cerebral ischemia, but in isolation may not be sufficient to determine the loci of vascular stenoses. The incongruence between angiographic and neuropsychological findings underlines the importance of distinguishing among different levels and types of measurements in defining subgroups of cerebral revascularization candidates. Collaboration among neuroscientists will further our understanding of the interrelationships among neurodiagnostic tests.
Further Studies with a Noninvasive Method of Intracranial Pressure Estimation
Authors: Donald York , Mark Legan , Steve Benner , Clark Watts
Published: August 2004

A linear relationship between elevated intracranial pressure in patients with hydrocephalus and with cerebral edema and a latency shift of the N2 wave of the flash-evoked cortical potential is demonstrated. Although the relationship is good at pressures of 200 to 300 mm H2O, it is excellent at pressures above 300 mm H2O. This relationship establishes a reliable noninvasive method of estimating intracranial pressure.
Treatment of Tic Douloureux and Hemifacial Spasm by Posterior Fossa Exploration: Therapeutic Implications of Various Neurovascular Relationships
Authors: Joseph H. Piatt , Robert H. Wilkins
Published: August 2004

A series of 152 posterior fossa explorations for tic douloureux and hemifacial spasm has been reviewed with assessment of outcome at the last follow-up examination. Among 103 cases of tic followed for an average of 48.3 months. 79 patients (77%) obtained good or excellent symptomatic relief, and there were 24 failures or recurrences (23%). Of 48 cases of hemifacial spasm followed for an average of 42.1 months, there were good or excellent results in 42 cases (87.5%); only 6 patients (12.5%) experienced failure or recurrence. Patients noted to have arterial contact at the 5th nerve entry zone responded significantly better to microvascular decompression than did patients with no arterial contact. Further, patients noted to have anatomical distortion of the 5th nerve by an artery or wedging of an artery into the crevice between the nerve and the pons had significantly better outcomes after microvascular decompression than did patients with other kinds of arterial contact. Partial sensory rhizotomy proved to be a highly effective alternative to microvascular decompression in cases of doubtful neurovascular compression. It was not possible to define similar neuroanatomical criteria predictive of response to microvascular decompression in patients with hemifacial spasm.
Successful Removal of an Arteriovenous Malformation in the Basal Ganglia
Authors: Rutka James T. , Tucker William S.
Published: August 2004

This report describes the successful removal of a ruptured dominant hemisphere arteriovenous malformation that arose in the region of the basal ganglia and was supplied by the lenticulostriate arteries. Obliteration of the lesion was accomplished by a transcerebral approach from above, utilizing the preexisting hematoma cavity.
Primary Intracranial Germinoma Presenting as Lower Cranial Nerve Involvement: Case Report and Review of the Literature
Authors: Aguila Luis A. , Chou Samuel M. , Bay Janet W.
Published: August 2004

Primary intracranial germinomas are classically known as midline lesions, occurring most commonly in the pineal and suprasellar regions, and will usually present with symptoms related to increased intracranial pressure or hypothalmic dysfunction. Involvement of both the pineal and the suprasellar region in the same patient (double midline lesions) is relatively rare (7%). Dissemination of germinoma to both cerebellopontine angles, in addition to the double midline lesions, with the initial clinical presentation of lower cranial nerve involvement has not been previously reported. We encountered such an unusual case, which prompted this report and review of the literature.
Liver Abscess: Complication of a Ventriculoperitoneal Shunt
Authors: Fisher Robert A. , Rodziewicz Gerard , Selman Warren R. , White Robert J. , Vibhakar Shardul D.
Published: August 2004

Liver abscess is a previously unreported complication of ventriculoperitoneal shunting. We present such a case, which was diagnosed by computed tomography (CT) and managed by CT-guided percutaneous catheter drainage of the liver abscess, appropriate antibiotics, and shunt externalization.
Vertebral Osteochondroma Causing Spinal Cord Compression: Case Report
Authors: Karian John M. , DeFilipp Gary , Buchheit William A. , Bonakdarpour Akbar , Eckhardt Wil
Published: August 2004

A case of spinal cord compression secondary to an osteochondroma of the vertebral body of T-4 is reported. Computed tomography aided in the display of the lesion and the planning of its resection.
Combined Supra-Infrasellar Approach for Large Pituitary Tumors
Authors: Loyo Mauro , Kleriga Enrique , Mateos Humberto , de Leo Roberto , Delgado Andres
Published: August 2004

A combined supra-infrasellar approach for the resection of very large pituitary tumors is described. We think that it is superior to either the transsphenoidal or the intracranial approaches to these difficult tumors.