bluuebunny/crossref_metadata_2025 huggingface dataset:
A metastasizing ependymoma of the cauda equina
Authors: Mavroudis Constantine , Townsend Jeannette J. , Wilson Charles B.
Published: May 2009

✓ A case is described in which a metastatic ependymoma of the cauda equina recurred after prolonged remission. Similarities to five previously reported cases are discussed, with emphasis on the mode of metastasis. Factors most closely associated with distant metastases include early onset, numerous local operations, long survival, and massive local recurrence at the time of distant metastases.
Pineocytomas presenting as subarachnoid hemorrhage
Authors: Steinbok Paul , Dolman Clarisse L. , Kaan Ken
Published: May 2009

✓ Two cases of pineocytoma are reported in patients whose initial symptoms resembled a subarachnoid hemorrhage. The underlying tumor became obvious only later in the disease. Several episodes of subarachnoid bleeding occurred. These are the first documented cases of pineocytoma with this type of clinical presentation.
Primary fibrosarcoma of the skull
Authors: Mansfield James B.
Published: May 2009

✓ A case of primary fibrosarcoma of the skull is presented. Only one other case with this uncommon site of occurrence of this tumor has been previously reported.
Modified suction tip
Authors: Shahbabian Set
Published: May 2009

✓ A modification of the standard suction tip is described that decreases risk to delicate tissues.
Manpower for neurosurgery: Seeing ourselves as others see us
Authors: Ginzberg Eli
Published: May 2009

✓ The 1977 Cushing Orator looks at the question of neurosurgical manpower and its relation to national health policies, proposed or abandoned. The impact on residency training as well as patient care and research effort require constant monitoring by the profession, so that the specialty will continue to contribute significantly to human betterment.
Cerebral arterial blood flow and aneurysm surgery
Authors: Nornes Helge , Knutzen Hanna Berit , Wikeby Per
Published: May 2009

✓ A study of 21 patients was conducted to clarify the autoregulatory capacity in patients subjected to induced hypotension during intracranial surgery for saccular aneurysms. Trimethaphan camsylate (Arfonad) was used for induced hypotension and arterial blood flow was measured with an electromagnetic flow probe on the internal carotid artery or one of its main intracranial branches. In Grade I and II patients the control arterial blood pressure (ABP) ranged from a mean of 90 to 135 mm Hg (average 110 mm Hg), with a lower level of autoregulation (LLAR) from 35 to 85 mm Hg (average 62 mm Hg). Grade III patients had a control ABP of between 105 and 145 mm Hg (average 124 mm Hg) and the LLAR was found to be between 60 and 95 mm Hg (average 76 mm Hg). There was a significant difference between the two groups with regard to both the control ABP and the LLAR. A surprising result obtained from these data was that the average lower autoregulatory range (the difference between control ABP and LLAR) is practically the same in the two groups. A systematic investigation of the upper limit of autoregulation was not possible for ethical reasons. In those few patients in whom spontaneous increase in the ABP made such observations possible, upper limits up to 150 mm Hg with a total autoregulatory capacity of about 75 mm Hg were observed. In some patients, however, lower limits and corresponding “breakthroughs” of cerebral blood flow were seen, demonstrating that the upper limit of autoregulation is markedly influenced by several factors.
Stereotaxic thrombosis of inaccessible intracranial aneurysms
Authors: Smith Randall W. , Alksne John F.
Published: May 2009

✓ Some intracranial aneurysms that might be considered inoperable by open craniotomy are readily treatable by stereotaxic thrombosis. This is possible because the stereotaxic technique requires only that some point on the fundus of the aneurysm can be punctured with a needle. Illustrative cases are given describing the successful treatment of aneurysms arising at the origin of the ophthalmic artery, within the cavernous sinus, within the sella turcica, and from the vertebrobasilar and the posterior inferior cerebellar arteries ventral to the brain stem. The aneurysms within the sella or cavernous sinus can be approached through the sphenoid sinus, and the aneurysms ventral to the brain stem can be approached through the clivus without opening the dura.
Transsphenoidal microhypophysectomy in acromegaly
Authors: Hoi Sang U , Wilson Charles B. , Tyrrell J. Blake
Published: May 2009

✓ From July, 1970, to March, 1975, 62 transsphenoidal operations were performed on 61 acromegalic patients (39 males, 22 females). Of these patients, 58 presented with symptoms of hypersecretion of human growth hormone (HGH), with relatively infrequent local effects. Each patient was evaluated neuroradiologically, and each tumor was classified as an enclosed or an invasive adenoma, with or without suprasellar extension. Anterior pituitary function was also evaluated for each patient, pre- and postoperatively. During the transsphenoidal procedure, selective gross total removal of the adenomatous tissue was attempted, and was successful in 53 patients; selective subtotal tumor removal was performed in eight patients.

In 38 patients who had not undergone prior therapy, a selective total excision was achieved in 36; of these, 30 patients were considered cured, on the basis of relief of clinical symptoms and reduction of the serum HGH level to below 10 mg/ml. There was no significant difference in cure rates between the enclosed and the invasive adenomas, and no cures were achieved by any procedure short of selective total tumor removal. In these latter cases, postoperative irradiation was employed. Eighteen patients had received prior therapy in the forms of cryohypophysectomy (eight cases), cryohypophysectomy and irradiation (two cases), craniotomy (two cases), craniotomy and irradiation (two cases), and irradiation alone (four cases). The treatment results in this group were less favorable. In the entire series of 62 operations, complications occurred in eight patients in the form of cerebrospinal fluid leak, meningitis, sinusitis, nasal-oral fistula, transient diabetes insipidus (six cases), and carotid and cavernous injuries. In the group of 43 previously untreated patients, endocrine complications occurred in five, of which only three have permanent deficits. In the previously treated 18 patients, one developed compromised pituitary function from the transsphenoidal procedure. In the entire series, there was no surgical mortality, although two patients died of surgically unrelated causes.
Clinical and endocrinological evaluation of 16 acromegalic patients treated by transsphenoidal surgery
Authors: Leavens Milam E. , Samaan Naguib A. , Jesse Richard H. , Byers Robert M.
Published: May 2009

✓ Sixteen patients with acromegaly treated with transsphenoidal pituitary surgery were evaluated with the measurement of serum human growth hormone (HGH) before and after intravenous stimulation with thyrotropin-releasing hormone (TRH). Fourteen of these patients showed a significant rise of serum HGH after TRH stimulation before surgery. After surgery, 12 patients with Grade 2 noninvasive adenomas had normal fasting serum HGH levels which did not stimulate with TRH. Two of these patients showed high serum HGH levels both at fasting and after TRH stimulation and required a second operation to remove residual adenoma within the sella before adequate lowering of HGH was achieved. Evidence of recurrent adenoma has not occurred clinically or biochemically in this group of 12 patients followed for an average of 24 months (2 to 60 months).

The results were unsatisfactory in four of these 16 patients. One patient who has a postoperative HGH of 9 ng/ml which still stimulates with TRH has made clinical improvement, but must have residual adenoma in the sella or invasive adenoma in the dura and tumor capsule. Additional treatment with irradiation has been given. Failure to achieve satisfactory results in the other three patients was attributed to the presence of locally invasive adenoma; one in the sphenoid sinus, and the other two possibly as a consequence of previous operative procedures.
Experiences with sterilization of the operating microscope
Authors: Kurze Theodore , Apuzzo Michael L. J. , Weiss Martin H. , Heiden James S.
Published: May 2009

✓ Experiments were conducted to assess the feasibility of both paraformaldehyde and ethylene oxide gas sterilization of the operating microscope. From these experiments and practical experience, it is concluded that ethylene oxide sterilization of the operating microscope is a feasible and desirable alternative to cumbersome draping techniques.
The true sagittal diameter of the cervical spinal canal and its diagnostic significance in cervical myelopathy
Authors: Hashimoto Isao , Tak Yoon-Kil
Published: May 2009

✓ A method is presented for measuring the true sagittal diameter of the cervical spinal canal on routine lateral radiograms by the use of a midline perforated ruler. Sagittal measurements were made in 92 normal adults to establish a range of normal values. The lower and upper limits were 10 mm and 17 mm, respectively, at the levels of C-3 to C-7. Comparison of the results with the anatomical measurements of dried specimens showed good agreement. Four cases of cord compression were presented and the diagnostic significance of the method in cervical myelopathy was discussed.
Pancreatitis following spinal cord injury
Authors: Carey Michael E. , Nance Francis C. , Kirgis Homer D. , Young Harold F. , Megison Lloyd C. , Kline David G.
Published: May 2009

✓ Six cases of pancreatitis following spinal cord injury are presented. No single, etiologically accepted mechanism already postulated to cause pancreatitis can account for all the cases reported. The authors hypothesize that spinal cord disruption may produce pancreatitis by sympathetic-parasympathetic nervous system imbalance resulting in over-stimulation of the sphincter of Oddi. This may lead to stasis of secretions with absorption of amylase into the systemic circulation, and structural pancreatic damage. Pancreatitis in those with cord injuries is easily overlooked because abdominal pain is usually absent and fever is usually attributed to more frequently occurring pulmonary or urinary tract infections. Recognition of this complication is important in order to decrease the morbidity and mortality that follows spinal cord damage.
Workshop on cancer of the brain
Authors: Bigner Darell D. , Wilson Charles B.
Published: May 2009

✓ The authors provide a summary of a workshop on “Cancer of the Brain.” This conference reviewed the current knowledge about the etiology and pathogenesis of human brain tumors and the experimental induction of comparable animal brain tumors, and considered new lines of research.
Chronic demeclocycline therapy in the syndrome of inappropriate ADH secretion due to brain tumor
Authors: Graze Kathleen , Molitch Mark E. , Post Kalmon
Published: May 2009

✓ The treatment of the syndrome of chronic inappropriate antidiuretic hormone (ADH) secretion by fluid restriction is often attended by poor patient compliance. The following case report illustrates successful management of this condition by oral demeclocycline therapy in a patient who had hyponatremia in association with angioblastic meningioma of the sphenoid ridge.
Embolism to the central nervous system from cardiac myxoma
Authors: Tipton B. King , Robertson James T. , Robertson Jon H.
Published: May 2009

✓ Two cases of left atrial myxoma are reviewed, both presenting as embolic phenomena. Neither patient gave a history compatible with pre-existent cardiac dysfunction. Sudden collapse and subsequent right hemiplegia resulted in one patient when an embolus lodged in the left middle cerebral artery. The second patient presented with headache and transient visual obscuration in the left eye. She showed evidence of embolism to the central retinal artery, and particulate matter could be seen within the retinal arterioles. Attention is drawn to the fact that echocardiography now constitutes a simple, noninvasive, and highly reliable method of making this diagnosis. The propensity for embolic tumor fragments to grow and invade cerebral arterial walls is discussed along with its possible neurosurgical significance.
Infantile chronic subdural hematoma of the posterior fossa diagnosed by computerized tomography
Authors: French Barry N. , Dublin Arthur B.
Published: May 2009

✓ A 9-week-old infant manifested continuous vomiting for 1 week accompanied by a tense fontanel, “sun setting” of the eyes, frequent opisthotonos, and hypertonicity. The head circumference was at the 50th percentile. Computerized tomography (CT) revealed acute hydrocephalus and a posterior fossa subdural hematoma. The brain stem and cerebellum were of greater density (54 Hounsfield units) than normal cerebral white matter (42 Hounsfield units) whereas the subdural hematoma was the same density as normal cerebral white matter (“isodense”). The cerebellum and brain stem became enhanced by contrast (68 Hounsfield units), but no enhancement occurred in the cerebral white matter or subdural hematoma. A shunt followed by occipital craniectomy resolved both the hydrocephalus and subdural hematoma. Repeat CT scan 15 days postoperatively disclosed continuing higher density of the cerebellum and brain stem (60 Hounsfield units) relative to cerebral white matter. Increased density of the infantile cerebellum has been noted previously but not to the same extent as in this patient.
Long-term control of recurrent cyst of the conus medullaris
Authors: Hoffman Harold J. , Holness Renn O. , Flett Norman R.
Published: May 2009

✓ The authors report a case in which decompression of an intramedullary epidermoid cyst was maintained by intermittent drainage via an implanted subcutaneous Ommaya reservoir.
Mixed bacterial meningitis: A complication of ventriculo- and lumboperitoneal shunts
Authors: Brook Itzhak , Johnson Neil , Overturf Gary D. , Wilkins Jeanette
Published: May 2009

✓ Infectious complications of ventriculo- and lumboperitoneal shunts in two patients are presented. Cerebrospinal fluid infection due to aerobic and anaerobic enteric flora was characteristic of each case. Both infections occurred several months after shunt surgery and were associated with colonic perforation by the distal limb of the peritoneal catheter. These cases emphasize this unusual hazard of peritoneal shunts and demonstrate methods for diagnosis and effective therapy.
Transsphenoidal microsurgical removal of 250 pituitary adenomas
Authors: Wilson Charles B. , Dempsey Lawrence C.
Published: May 2009

✓ In a series of 250 pituitary adenomas, 72 (28.8%) were nonsecreting and 178 (71.2%) produced a hypersecretion syndrome: human growth hormone (83), prolactin (59), and adrenocorticotropic hormone (ACTH) (36). One-fifth had received prior treatment and one-fourth had visual impairment. The technical aspects of the trans-sphenoidal procedure are given with separate consideration of microadenomas and larger tumors. The results are provided in summary form with emphasis on the favorable outcome following removal of microadenomas. There was one postoperative death, and the complications observed after operation are presented.
Coexisting pituitary adenomas and partially empty sellas
Authors: Domingue James N. , Wing S. Douglas , Wilson Charles B.
Published: May 2009

✓ Seventeen cases of coexisting secreting pituitary adenomas and partially empty sellas are presented. The location of the cisternal invagination into the sella was not helpful in predicting the location of the tumor. In patients with endocrine indication of a secreting pituitary neoplasm, the finding of a partially empty sella should not contradict the diagnosis.
SEM evaluation of endothelial damage following temporary middle cerebral artery occlusion in dogs
Authors: Dujovny Manuel , Osgood Carroll P. , Barrionuevo Pedro J. , Perlin Alfred , Kossovsky Nir
Published: May 2009

✓ Microsurgical clips and tourniquets were used to occlude middle cerebral arteries of dogs for 45-minute periods. Scanning electron microscopy and light microscopy studies revealed significant endothelial damage in many of these arteries. Less traumatic microsurgical clips are needed for temporary small vessel occlusion.
Ultrastructural changes in feline arterial endothelium following subarachnoid hemorrhage
Authors: Mayberg Marc R. , Wayne Houser O. , Sundt Thoralf M.
Published: May 2009

✓ Scanning electron microscopy of feline basilar arterial endothelium 4 hours and 1, 3, 5, and 7 days after subarachnoid hemorrhage (SAH) showed longitudinal furrows that correlated with angiographically demonstrated vasospasm. These ridges persisted after fixation at physiological pressure, and probably reflected medial contraction with undulation of the underlying elastic lamina. No change in endothelial cell morphology or thrombogenesis was observed as long as 7 days after SAH. There is no evidence from this study to suggest that ischemia from vasospasm is a product of thromboembolism from damaged endothelial surfaces.
Complications of dorsal column stimulation
Authors: Pineda Anselmo
Published: May 2009

✓ The complications associated with 92 dorsal column stimulator implants are reported. They were of two types, technical and functional. In all there were 58 significant complications. Most technical complications were correctable but complications difficult to correct occurred in 26 patients. Late failure in stimulation was observed in 32 implants that had given excellent pain control for periods ranging from months to years. Improvements in the results of this procedure may be achieved by future technical developments and by clarification of physiological mechanisms.
Pineal and suprasellar germinomas
Authors: Jenkin R. Derek T. , Simpson W. John K. , Keen Colin W.
Published: May 2009

✓ The results of radiation treatment of 52 patients with a tumor in the pineal region or a suprasellar germinoma are analyzed. The overall 5-year survival rate was 59%. Ten patients in whom initial biopsy confirmed pineal germinoma were all alive 2 to 121 months from diagnosis, although two developed meningeal seeding at 2 and 7 months. Twelve of 15 patients 25 years old or younger with an unbiopsied tumor in the pineal region were alive 12 to 225 months after irradiation, with a 5-year survival rate of 81%. In comparison only five of 16 patients older than 25 years with a pineal region tumor survived, a 5-year survival rate of 37%. This marked age dependence in survival rates was attributed to a high proportion of germinomas in the younger patients and gliomas in the older patients.
Extrapyramidal disorder with pineal germinoma
Authors: Lins Marilyn M. , McDonnell Dennis E. , Aschenbrener Carol A. , Cancilla Pasquale A.
Published: May 2009

✓ Space-occupying lesions of the basal ganglia are a rare cause of extrapyramidal dysfunction in children. Metastatic pineal germinoma in both basal ganglia produced dystonia in a 12-year-old boy. The literature is reviewed. Extrapyramidal manifestations in this child are compared with previously reported cases of basal ganglia neoplasms.
Bilateral carotid-cavernous fistulae of mixed types with unusual radiological and neuropathological findings
Authors: Ambler Mary Webb , Moon Alfred C. , Sturner William Q.
Published: May 2009

✓ This report describes a case of bilateral post-traumatic carotid-cavernous fistulae (CCF), of both typical and atypical types, with delayed clinical deterioration. Unusual neuropathological lesions, distinctive from those due to direct cerebral trauma, are related to combined arterial ischemia and venous hypertension. Atypical CCF is not necessarily a benign disorder. Radiological monitoring is essential to detect spontaneous progressive intracranial shunting, to predict areas that are at risk from venous hypertension, and to identify remote sites of circulatory vulnerability.
Period of risk for recurrence in medulloblastoma
Authors: Quest Donald O. , Brisman Ronald , Antunes Joao L. , Housepian Edgar M.
Published: May 2009

✓ Ninety-nine patients with medulloblastoma who received surgery and radiotherapy, and had a statistically sufficient follow-up period were analyzed for factors influencing survival and the relevance of the “period of risk for recurrence” hypothesis. This postulate states that the period of risk for recurrence of a congenital tumor is equal to the age at presentation of illness plus 9 months' gestational time. The assumption is made that a tumor of embryonic origin will become manifest after a period of time determined by its inherent rate of growth and that tumor cells surviving treatment will multiply and present with recurrence in an equal period of time. Ten of 43 patients survived the period of risk, a presumed cure rate of 23%. None of these patients has subsequently developed evidence of tumor recurrence. Older patients at initial surgery had a somewhat greater survival rate for the first 5 years after treatment (10 of 26 older patients (38%) versus 15 of 54 younger patients (28%)), but by 10 years there was no appreciable difference in survival rates between those over 16 years of age and those younger. The beneficial effect of total neuraxis megavoltage radiotherapy is indicated by the improved 5-year survival rate from 9 of 41 patients (22%) to 16 of 39 patients (41%) with the newer techniques.
Intercellular granules and vesicles in prolonged cerebral vasospasm
Authors: Tani Eiichi , Yamagata Shogo , Ito Yuko
Published: May 2009

✓ Prolonged vasospasm was produced in the dog basilar arteries by introduction of fresh arterial blood or norepinephrine into the chiasmatic cistern. Myonecrosis was limited to a small number of smooth-muscle cells, and a large number of muscle cells appeared intact. The most characteristic change was the appearance of aggregated granules and vesicles in the widened extracellular space between smooth-muscle cells, particularly near the adventitia and the elastic lamina. The granules were spherical, 50 to 100 nm in diameter, often surrounded by a single membrane, and contained a dense osmiophilic core, about 40 to 90 nm in diameter. In addition, the elastic lamina often became loose and corrugated or broken.
The mega cisterna magna
Authors: Adam Rasheed , Greenberg Jack O.
Published: May 2009

✓ Eleven cases of enlarged cisterna magna were found in a series of 3000 computerized tomography scans. We believe mega cisterna magna by itself is not related to any specific symptoms and may not require further study or treatment.
Carotid endarterectomy
Authors: Dirrenberger Richard A. , Sundt Thoralf M.
Published: May 2009

✓ The healing of the canine carotid endarterectomy was defined at intervals from 30 minutes to 3 months after surgery by means of angiography, light microscopy, and scanning electron microscopy. Immediately after flow was established, a fibrin-platelet carpet formed on the endarterectomized surface. A typical thrombus formed on this initial layer resulting in vessel occlusion in 52% of non-heparinized animals. By 48 hours after surgery, there was little evidence of active thrombus formation, and reendothelialization from existing endothelial cells was noted. One week later, most of the mural thrombus had disappeared and re-endothelialization was well underway; by 3 months after surgery, re-endothelialization was complete. Intraoperative heparinization resulted in a striking reduction in mural thrombus formation and 100% patency rate. Vessel closure with vein-patch grafts resulted in no improvement of vessel patency. However, the results of this aspect of the study cannot be totally extrapolated to human carotid endarterectomy for the reasons discussed. The survival of the vein-patch grafts was investigated.
Enflurane anesthesia and changes of intracranial pressure
Authors: Boop Warren C. , Knight Richard
Published: May 2009

✓ Enflurane has been recommended by some as an ideal agent for use in neuroanesthesia. There is no statistically significant alteration of normal intracranial pressure with enflurane anesthesia. However, supporting a clinical impression, this study demonstrates in dogs that enflurane will significantly increase an already elevated intracranial pressure.
Hyperemia, CO2 responsiveness, and autoregulation in the white matter following experimental spinal cord injury
Authors: Smith Andrew J. K. , McCreery Douglas B. , Bloedel James R. , Chou Shelley N.
Published: May 2009

✓ The authors present the results of a controlled, randomized study of alterations in spinal cord blood flow, CO2 responsiveness, and autoregulation following experimental spinal cord injury in cats. Permanent paraplegia is shown to be associated with persistent hyperemia, loss of CO2 responsiveness, and impaired autoregulation in the white matter at the injury site. Probable mechanisms underlying these changes in spinal cord vasomotor control are discussed. Marked similarities between vascular responses of injured spinal cord and luxury perfusion of the brain are pointed out.
Obliterative arachnoiditis complicating lumbar spinal stenosis
Authors: Epstein Joseph A. , Epstein Bernard S. , Lavine Leroy S. , Rosenthal Alan D. , Decker Robert E. , Carras Robert
Published: May 2009

✓ The authors report five patients with spinal stenosis who had a total myelographic block at the level of the obliterated subarachnoid space. Arachnoiditis had not been considered as a primary diagnosis until laminectomy revealed a non-pulsating, thickened dural sac that conformed to the internal configuration of the involved spinal canal. Two patients had stenosis complicated by spondyloarthrosis over multiple lumbar levels, one had a previous spinal fusion, another had degenerative spondylolisthesis, and the fifth had a large midline extruded disc at L2–3 that completely blocked the spinal canal. The dura was opened in two patients, confirming the lesion. Despite obliteration of the subarachnoid space, significant relief for approximately 1 year followed decompressive laminectomy, foraminotomy, and discectomy, with disappearance of neurogenic claudication in three patients. Postoperative erect films showed no caudad passage of contrast. While further observations are required, an awareness of this complication of spinal stenosis is important in the diagnosis and management of such patients and in evaluating their ultimate prognosis.
Role of vascular proliferation on angiographic appearance and encapsulation of experimental traumatic and metastatic brain abscesses
Authors: Wood James H. , Doppman John L. , Lightfoote William E. , Girton Mary , Ommaya Ayub K.
Published: May 2009

✓ Experimental traumatic abscesses were produced in rhesus monkeys by intracerebral injection of nutrient agar contaminated with Staphylococcus epidermidis, and metastatic abscesses were induced by intracarotid embolization of silicone cylinders contaminated with Staphylococcus epidermidis. All monkeys underwent preoperative and serial postoperative carotid angiography. Traumatic abscesses produced early capsular blushes and progressive anterior cerebral artery displacements. Metastatic abscesses induced transient midline shifts but no capsular stains. Postmortem studies on the monkeys showed that mean capsular thickness and segmental wall vascularity of the traumatic and metastatic abscesses were significantly different (p < 0.001), despite equal abscess ages and similar abscess volumes. In comparison to traumatic abscesses, metastatic abscesses demonstrated reduced inflammatory cell infiltration and retarded collagen formation around proliferating capsular vessels. Brain surrounding the metastatic abscesses demonstrated ischemic changes. The results suggest that 1) capsular blushes during cerebral angiography are secondary to vascular proliferation within the capsule and not to compression of surrounding brain, 2) vascular staining reflects capsular thickness, 3) capsular vascularity contributes to collagen formation, 4) encapsulation is dependent upon the integrity of surrounding brain, and 5) adjacent cerebral ischemia may impede inflammatory responses involved in capsule formation.
Primary malignant schwannoma of the Gasserian ganglion
Authors: Hedeman Lynn S. , Lewinsky Bernard S. , Lochridge G. Kress , Trevor Richard
Published: May 2009

✓ The diagnosis, radiographic features, clinical presentation, and treatment of two cases of primary malignant schwannoma of the Gasserian ganglion are discussed. Radiographic differentiation from trigeminal neurinoma is not possible; however, erosion of the foramina favors a diagnosis of malignancy. Radiation therapy was successful in the management of both cases and is recommended for extensive lesions.
Mucoceles with intracranial and extracranial extensions
Authors: Diaz Fernando , Latchow Richard , Duvall Arndt J. , Quick Cedric A. , Erickson Donald L.
Published: May 2009

✓ Two cases of unusual childhood mucocele are presented. These serve to illustrate the great potential these lesions have for slow, insidious development and insinuation of themselves into regions of the head and face where they are difficult to remove surgically. A description of the staged surgical excision is presented to emphasize the importance of radical removal of these benign lesions.
Endoscopy of Meckel's cave, cisterna magna, and cerebellopontine angle
Authors: Fukushima Takanori
Published: May 2009

✓ A new 1.45-mm endoscope is described that can be inserted through a thin-walled No. 16 needle. The instrument was used in 10 cadavers for endoscopic exploration of the cisterna magna, the C1–2 space, Meckel's cave, and the cerebellopontine angle. Its potential clinical application is discussed.
Percutaneous epidural stimulation of the spinal cord for relief of pain
Authors: Urban Bruno J. , Nashold Blaine S.
Published: May 2009

✓ Percutaneous epidural stimulation of the spinal cord was carried out in 20 patients with intractable pain. The procedure proved simple, and no major complications were encountered. The long-term results were comparable to the results obtained after a dorsal column stimulator implant by laminectomy. The percutaneous technique allowed extended trial stimulation without committing the patient to a major operation. Those patients in whom stimulation did not alleviate pain could be identified during a 2-week observation period, and the system could be removed easily. Seven patients were placed on chronic autostimulation and only one of those failed to experience continuing pain relief throughout the follow-up time of up to 2 years. It is concluded that percutaneous epidural stimulation constitutes a valid alternative to dorsal column stimulator implantation.
Bacterial intracranial aneurysm
Authors: Bohmfalk George L. , Story Jim L. , Wissinger John P. , Brown Willis E.
Published: May 2009

✓ The authors tabulate and analyze cases of bacterial intracranial aneurysm documented since 1954, and add four of their own. In 85 cases the overall mortality was 46%. Elimination of patients dying before reaching the hospital makes this figure spuriously low. Figures for patients hospitalized for endocarditis before neurological symptoms occurred suggest a true mortality of 80% from aneurysms that rupture and 30% if the aneurysm remains intact. Multiple reports of spontaneously resolving, enlarging, diminishing, multiple, and sequentially appearing aneurysms, all of which occurred in our fourth case, clarify the need for complete and sequential angiography. Computerized tomographic (CT) scanning in this disease has not been reported, but our experience with these scans demonstrates considerable potential value.

A protocol of complete cerebral angiography and CT scanning of these neurologically asymptomatic patients is proposed, in order to assess the true incidence of bacterial intracranial aneurysm, to learn more of its natural history, and to prevent some neurological catastrophes.
Preliminary evaluation of cerebellar stimulation by double-blind stimulation and biological criteria in the treatment of epilepsy
Authors: Van Buren John M. , Wood James H. , Oakley John , Hambrecht Frederick
Published: May 2009

✓ This series included five patients who had suffered 8 to 23 years of severe, medically intractable seizures without remission, severe socioeconomic handicaps, and an average of over one seizure a day on hospital observation and by history. All had combinations of partial and general seizures with focal and/or bilaterally synchronous epileptiform activity consistently on multiple electroencephalograms (EEG's). One patient had nearly continuous myoclonic activity. Serum levels of phenytoin, primidone, and phenobarbital were adjusted to therapeutic ranges. Three patients had additional medication (diazepam, ethosuximide). Cerebellar biopsy in three patients showed reduction in Purkinje cells.

After implantation of cerebellar stimulators, seizure frequency was evaluated in hospital during three or four admissions for 4- to 6-week periods over the ensuing 15 to 21 months. No slow trends toward improvement or deterioration were noted. No significant differences in seizure frequency were found when comparing intervals of about 7 days of on-and-off stimulation both in the double-blind and unblinded conditions. No changes in EEG or Intelligence or Memory Quotients occurred unaccounted for by variations in serum levels of antiepileptic drugs. Despite the lack of objective improvement, patient and family acceptance of cerebellar stimulation was positive to enthusiastic. A rise in CSF norepinephrine and a fall in gamma aminobutyric acid (GABA) accompanied cerebellar stimulation and may be related to the results.
Effect of atropine on cerebrovascular responsiveness to carbon dioxide
Authors: Matsuda Masayuki , Yoneda Shunichi , Gotoh Hiroshi , Handa Jyoji , Handa Hajime
Published: May 2009

✓ Effects of cholinergic inhibition by atropine on cerebral circulation were studied in 15 baboons anesthetized with sodium pentobarbital. Intravertebral infusion of atropine, 0.1 mg/kg, did not cause any changes in cerebral blood flow (CBF), superior sagittal sinus wedge pressure (SSWP), epidural pressure (EDP), cerebral perfusion pressure, or cerebral vascular resistance under normal conditions. Cerebrovascular responsiveness to carbon dioxide (CO2) inhalation was not influenced by atropine. The presence of cholinergic nerve fibers has been proved in the cerebral blood vessels and the existence of cholinergic mechanism suggested in the brain stem, but it is not likely that the cholinergic nerves have tonic control of cerebral blood vessels in the resting state or affect cerebrovascular responsiveness to CO2. The changes in EDP and those in SSWP showed a very good correlation to each other. There was also a good correlation between the changes in CBF and those in EDP or SSWP.
Fascicular nerve allograft evaluation
Authors: Levinthal Robert , Brown W. Jann , Rand Robert W.
Published: May 2009

✓ In a comparative experiment, transplantation of orthotopic nerve fascicle was performed on 100 sciatic nerves between inbred, antigenically identified rats. The authors studied cellular response, macrophage reaction, connective-tissue reaction, myelination, and distal/proximal axonal ratios, but no difference could be established between allografted and autografted fascicles after 2 months. Moreover, there was no evidence of any graded rejection phenomenon dependent on differences of tissue typing. Theories for the decreased antigenic reaction of nerve fascicles are proposed.
A mitochondrial lesion in experimental spinal cord trauma
Authors: Ito Terifumi , Allen Norman , Yashon David
Published: May 2009

✓ Cytochrome oxidase activities were determined by a microspectrophotometric method on microdissected samples of gray and white matter from frozen-dried sections of dog spinal cord. Experimental animals received 400 gm-cm impact at the T-3 to T-4 level. Sections for enzyme analysis and histological study were taken at the center of the trauma site, at successive 1-mm distances from the center, and at non-traumatized segments. A drop in cytochrome oxidase activities to approximately 50% of normal value was found as early as 15 minutes post-trauma, with greatest decrease at the trauma center and lesser effects at successive distances. This effect was related to known morphological defects in mitochondrial cristae and inner membranes. The enzyme change was significantly correlated with histological estimates of gray matter and neuronal damage, but was also partially independent of these processes. A small but significant increase of enzyme activity in white matter at the trauma site was considered most likely attributable to mitochondrial accumulations due to impaired axoplasmic flow.
Spontaneous healing of intracranial aneurysms after subarachnoid hemorrhage
Authors: Edner Göran , Forster David M. C. , Steiner Ladislau , Bergvall Ulf
Published: May 2009

✓ A case of spontaneous intra-aneurysmal thrombosis, verified angiographically, is reported in a patient with subarachnoid hemorrhage and without surgical intervention. The frequency of such an occurrence and the factors involved are reviewed and discussed.
Anterior inferior cerebellar artery aneurysms
Authors: Johnson James H. , Kline David G.
Published: May 2009

✓ A 54-year-old man experienced a right occipital headache accompanied by a roaring sound, nausea, vomiting, right facial weakness, and stiff neck. Vertebral angiography revealed an aneurysm of the right anterior inferior cerebellar artery (AICA) at the internal acoustic meatus which was later excised with favorable results. The literature is reviewed; operations have been reported in eight other cases. Inconstant waxing and waning cerebellopontine angle symptoms and signs can be found when a history of subarachnoid hemorrhage is lacking.
Extramedullary hemangioblastoma of the spinal cord
Authors: Wisoff Hugh S. , Suzuki Yamato , Llena Josefina F. , Fine David I. M.
Published: May 2009

✓ A case of hemangioblastoma of the spinal cord is described in which the tumor presented in an intradural extramedullary location. The patient did not have von Hippel-Lindau's disease or metastatic seeding. It is assumed that the tumor arose in the pia, and its direction of growth was purely extramedullary.
Clinicopathological study of cerebral aneurysms
Authors: Suzuki Jiro , Ohara Hiro
Published: May 2009

✓ The origin and mechanism of rupture, repair, and growth of intracranial saccular aneurysms are reported in an investigation of 45 aneurysms (23 unruptured and 22 ruptured) found in 34 brain specimens. Gaps in the media at the bifurcations of cerebral arteries are important for aneurysmal formation. The walls of aneurysms smaller than 3 mm in diameter are mainly composed of endothelial cells, and fibrous tissue. When aneurysms grow larger than 4 mm, the walls become collagenous and extremely thin portions develop in their domes, forming potential rupture points. Immediately after the rupture, bleeding is stopped by clot and a new fibrin layer is formed around the rupture point. It is proposed that the cerebrospinal fluid has a special accelerating action in clot formation. This fibrin layer is weak, and repeat rupture occurs within 3 weeks after the initial hemorrhage. However, after 3 weeks, rebleeding is rare due to the reinforcement of this layer, and capillaries appear in this new wall. Hemorrhages from these capillaries occur within and outside the new wall caused by the constant impingement of blood flow. In severe cases, the aneurysm ruptures again, but when the hemorrhages are slight, the aneurysm grows as the wall is thickened by repeated hemorrhages and their absorption. This may explain the growth mechanism of the aneurysm.
Cerebral artery spasm
Authors: Hughes J. Trevor , Schianchi Pietro M.
Published: May 2009

✓ From a larger series of autopsies with subarachnoid hemorrhage (SAH), 20 cases were selected for the known complication of cerebral vasospasm. Evidence for vasospasm was radiological and pathological in 17 cases and pathological alone in three. A systematic histological examination of the large arteries in places known formerly to have been in spasm showed that, in the 12 early cases (death before 3 weeks), there were relevant changes in all the layers of the arterial wall, the most significant being evidence of necrosis in the tunica media. In the eight late cases (death after 3 weeks), in addition to the sequelae of the earlier acute changes, there was marked concentric intimal thickening by subendothelial fibrosis, again located in the segments of arteries formerly in spasm. Changes were also found in the small arteries, capillaries, and veins, both in the early and late cases but these changes, although striking, were thought to be caused by the ischemia due to the vasospasm; similar changes were also seen in the control cases with ischemia from arterial occlusion.
Aphasia and left thalamic hemorrhage
Authors: Reynolds Arden F. , Harris A. Basil , Ojemann George A. , Turner Paul T.
Published: May 2009

✓ Left thalamic hemorrhage as a cause of aphasia has not been widely recognized. Large thalamic hemorrhages cause coma, making speech examination impossible; smaller thalamic hemorrhages were difficult to document until recent diagnostic advances. Nine cases of thalamic hemorrhage with aphasia have been described in the literature. This report presents four additional cases. These patients had acute onset of aphasia, supranuclear paralysis of upward gaze, right hemisensory deficits, and mild right hemiparesis. Three of the four patients responded to ventriculostomy drainage with rapid clearing of the supranuclear paralysis of upward gaze, and two later required placement of permanent ventricular shunts. After 1 year, two patients exhibited no clinically detectable speech malfunction and the other two were severely aphasic. The hemiparesis, hemisensory deficits, and ocular pareses all cleared. These cases are discussed with respect to present models of the role of the thalamus in speech.
Pharmacokinetics of intracarotid artery 14C-BCNU in the squirrel monkey
Authors: Levin Victor A. , Kabra Pokar M. , Freeman-Dove Mary A.
Published: May 2009

✓ A comparison of intravenous to intracarotid artery (ICA) administration of14C-BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) was made in squirrel monkeys. Radioactivity was measured as soluble drug products and as RNA-, DNA-, and protein-bound radioactivity. The ICA administration of BCNU achieved 190% to 280% higher brain nucleic acid-bound drug levels than use of the intravenous route in the infused hemisphere and 130% to 280% higher levels than in the noninfused hemisphere. In addition, some brain regions directly subserved by the middle cerebral artery had bound drug levels four- to fivefold greater than those found in regions of noninfused brain. The data suggest that a need for BCNU dose reduction due to myelotoxicity may be an indication for ICA therapy in selected brain-tumor cases.
The effect of dexamethasone on electroencephalograms in patients with brain tumors
Authors: Matsuoka Shigeaki , Arakaki Yoshihiro , Numaguchi Kotaro , Ueno Shoogo
Published: May 2009

✓ Nine patients with primary or metastatic brain tumors were examined with topographic computer display of delta activity before and after administration of dexamethasone. In six cases with primary malignant or metastatic brain tumors a diminution of delta distribution was observed following intravenous administration of dexamethasone, and no significant changes of the topographic map of the delta wave were obtained in two cases of benign brain tumor without clinical signs of increased intracranial pressure. Some of the changes of delta activities are believed to be correlated with the amount of peritumor edema. It is noteworthy that the change of focal delta activities by steroid was detected 20 minutes after administration.
Surface ultrastructure of tissues occluding ventricular catheters
Authors: Collins Patricia , Hockley Anthony D. , Woollam David H. M.
Published: May 2009

✓ Specimens of material occluding ventricular catheters removed at shunt revision operations were studied by scanning electron microscopy. Immediate fixation allowed examination of human choroid plexus and ependyma which resembled living tissue.
Metallurgical analysis of aneurysm and microvascular clips
Authors: DeLong W. Bradford , Ray Robert L.
Published: May 2009

✓ The design of an aneurysm clip and the choice of its component materials require complex considerations of corrosion resistance, biocompatibility, desired performance, and manufacturing practicalities. This study analyzed 10 different types of aneurysm and microvascular clips for chemical composition and metallurgical characteristics. The opening force of each clip was determined with a spring gauge.

All components of four multicomponent clips (three aneurysm clips and one microvascular clip) were manufactured from 17-7PH stainless steel, a strong precipitation-hardening grade of good general corrosion resistance. Two multicomponent clips (one aneurysm clip and one microvascular clip) each contained three components manufactured from different alloys. In an implanted clip, an increased rate of corrosion may result from electrolytic reaction between components composed of different alloys.

This study demonstrated that 17-7PH stainless steel is a popular alloy for use in vascular clips, but it has several drawbacks. The authors suggest that manufacturers explore the use of PH15-7Mo instead. PH15-7Mo is another precipitation-hardening stainless steel, but contains molybdenum, which renders it potentially more resistant to corrosion than 17-7PH.
Spinal intramedullary metastatic medulloblastoma
Authors: Zumpano B. Joseph
Published: May 2009

✓ Metastatic spread of medulloblastoma along the neuraxis by leptomeningeal seeding through the cerebrospinal fluid pathways is well known. The occurrence of extracranial metastases outside the neuraxis has been well established, but the occurrence of intramedullary spinal cord metastases not related to surface seeding is rare. A histologically documented case of the latter type is described.
Atlantooccipital instability
Authors: Finney H. Lee , Roberts Theodore S.
Published: May 2009

✓ A patient is presented who had neck pain and transient episodes of visual-field defect followed by unconsciousness when he hyperextended his neck. Radiographic examination revealed atlantooccipital instability on flexion and extension views. Treatment by fusion of the occiput to C-2 resulted in relief of symptoms.
Basal rupture of saccular aneurysm
Authors: Fisher C. Miller , Ojemann Robert G.
Published: May 2009

✓ In a case of subarachnoid hemorrhage, the arteries of the circle of Willis were left undisturbed and undissected at postmortem examination. A block of frontal lobe tissue with the attached vessels was serially sectioned disclosing in its entirety a saccular aneurysm that had ruptured at the base rather than the dome. The histology of the hemostatic process was clearly depicted.
Xanthogranulomas of the choroid plexus in a neuro-epileptic child
Authors: Terao Hideo , Kobayashi Shu , Teraoka Akira , Okeda Riki
Published: May 2009

✓ Bilateral xanthogranulomas arising from both choroid plexuses were found in a 6-year-old child with epileptic seizures and psychomotor retardation. Both masses were surgically removed without adding any neurological deficits. The xanthogranulomas were fairly large, and the posterior part of both lateral ventricles were slightly dilated, but clinical symptoms and the location of the xanthogranulomas could not be clearly correlated in this case.
Wire closure of intracranial arteriotomy
Authors: Kapp John P. , Robertson James T. , Gielchinsky Isaac
Published: May 2009

✓ A technique is described for closure of intracranial arteriotomies in areas of difficult exposure, using wire sutures that can be twisted rather than tied.
A newly designed multipurpose microneurosurgical head frame
Authors: Sugita Kenichiro , Hirota Toshiyuki , Mizutani Tetsuro , Mutsuga Naomi , Shibuya Masato , Tsugane Ryiichi
Published: May 2009

✓ A new multipurpose head frame has been designed for microneurosurgery. It consists of a head holder with a frame to hold self-retaining brain retractors, hand rests, instrument holders, a plate for cotton patties, and skin-flap retractors. It has been satisfactorily used in 100 operations for 1 year.