bluuebunny/crossref_metadata_2025 huggingface dataset:
Extradural spinal involvement by gout
Authors: Wald Steven L. , McLennan James E. , Carroll Richard M. , Segal Harold
Published: May 2009

✓ A case of extradural gouty tophus in the lumbar region in a teen-age girl is presented as an addition to the differential diagnosis of erosive lesions of the spinal canal.
Primary intracranial endodermal sinus tumor
Authors: Eberts Thomas J. , Ransburg Robert C.
Published: May 2009

✓ Endodermal sinus tumor (yolk sac carcinoma), a germinal neoplasm, is rarely primary in the cranial cavity. The authors add a third case with the tumor located in the anterior third ventricular (suprasellar) region to the literature. Seventeen previously reported intracranial cases, mostly in the pineal region, are briefly reviewed.
Bilateral trigeminal neurofibrosarcoma
Authors: Liwnicz Boleslaw H.
Published: May 2009

✓ An autopsied case of bilateral trigeminal neurofibrosarcoma is reported. The right-sided inferior alveolar tumor was treated surgically and subsequently irradiated. There was no local recurrence during the ensuing 4 years. Two years after excision of that tumor, a left-sided trigeminal neurofibrosarcoma was subtotally removed. Two years later this same tumor was found to have extensively invaded the pons.
Arterial cross compression of the trigeminal nerve at the pons in trigeminal neuralgia
Authors: Haines Stephen J. , Martinez A. Julio , Jannetta Peter J.
Published: May 2009

✓ The autopsy findings in a patient with trigeminal neuralgia who died from unrelated causes are presented. Arterial cross compression of the appropriate trigeminal nerve at the pons was demonstrated. The relationship of arterial cross compression to trigeminal neuralgia is briefly discussed.
Macrophages in experimental and human brain tumors
Authors: Morantz Robert A. , Wood Gary W. , Foster Marsha , Clark Martina , Gollahon Katherine
Published: May 2009

✓ Although the presence of lymphoreticular cells within tumors has been recognized for over 100 years, it is only within the last decade that the concept has arisen that standard histological examination techniques may lead to an underestimation of the true extent of tumor infiltration by lymphoreticular cells, and particularly by macrophages. The macrophage content of certain systemic tumors has been correlated with their immunogenicity and growth characteristics. Since the central nervous system is to some extent an “immunologically privileged site” and contains within it specialized reticuloendothelial cells called microglia, the authors determined the macrophage content of three rodent brain-tumor cell lines, and attempted to correlate this macrophage content with their immunogenicity and growth characteristics. Their findings indicate a direct correlation between the immunogenicity and macrophage content of these three neural tumor cell lines.
Macrophages in experimental and human brain tumors
Authors: Morantz Robert A. , Wood Gary W. , Foster Marsha , Clark Martina , Gollahon Katherine
Published: May 2009

✓ The authors have analyzed 47 tumors of the central nervous system (11 glioblastomas, nine meningiomas, three medulloblastomas, 12 assorted primary neural tumors, and 12 brain metastases) for their content of macrophages. Cell suspensions were prepared by enzymatic digestion and macrophages were quantitated by IgGEAC rosette formation. Adsorption of sensitized indicator cells (EA) to sections of tumor was used as a measure to determine the distribution of IgGFc receptor-positive cells within the tumors and to serve as a control for selective release of IgGFc receptor-positive cells by enzyme digestion. The 11 glioblastomas had a mean macrophage content of 45% (range: 8% to 78%), the nine meningiomas had a mean of 44% (range: 5% to 81%), the three medulloblastomas a mean of 6% (range: 2% to 15%), and the metastatic tumors a mean of 24% (range: 4% to 70%). Adsorption of EA demonstrated that IgGFc receptor-positive cells were distributed throughout the tumor mass, although different types of patterns were observed. There was an excellent correlation between the percent of IgGEAC positive cells in suspensions and the extent of EA adsorption to the tumor sections. Compared to systemic neoplasms, most nervous system tumors have a high macrophage content. It is possible that the high macrophage content of brain tumors is related to their immunogenicity, and may be a partial explanation for the rarity of brain-tumor metastases.
Computerized tomography scanning appearances of intracranial meningiomas
Authors: Vassilouthis John , Ambrose James
Published: May 2009

✓ The computerized tomography (CT) scans of 102 patients with meningiomas confirmed at operation and histologically were reviewed, and the features displayed by the tumors were correlated with their histology. There were 54 transitional, 17 fibroblastic, 13 mixed transitional and fibroblastic, 10 angioblastic, and eight syncytial meningiomas. It was found that each of these meningioma variants exhibited common CT features that could be helpful in predicting the probable histology. These common features were: visible calcium aggregates, degree of surrounding edema, tumor density before and after contrast medium enhancement, homogeneity, and definition of outline. Visible calcium aggregates pointed to a diagnosis of either transitional or fibroblastic meningioma. None of the angioblastic or syncytial variants exhibited this feature. Most of the tumors were surrounded by edema of varying degrees (92%) but this was not considered to be a specific feature except perhaps in the fibroblastic type where the edema was almost invariably of moderate degree. Tumor attenuation values unenhanced by contrast medium were also nonspecific but in enhanced scans a homogeneous density distribution pointed to the tumor being most probably of the transitional type. The angioblastic and syncytial variants showed a marked tendency to exhibit low-density non-enhancing “cystic” areas or poorly defined, irregular tumor margins or fringes. All of the fibroblastic, transitional, or mixed fibroblastic and transitional variants were well defined with more or less regular shapes. The presence of marked edema, absence of visible calcium aggregates, non-homogeneous contrast enhancement with non-enhancing “cystic” components and poorly defined irregular borders point to aggressive or invasive characteristics more commonly found in the angioblastic and syncytial variants.
Use of computerized tomography scanning in supratentorial arachnoid cysts
Authors: Anderson Frank M. , Segall Hervey D. , Caton William L.
Published: May 2009

✓ Congenital supratentorial arachnoid cysts are large lesions that tend to cause severe distortion and compression of the brain, particularly in infants and children. Diagnosis of such cysts has often been delayed and uncertain in the past, but development of computerized tomography (CT) has greatly improved the ease and accuracy of their identification, helping to provide for earlier surgical treatment and better care of patients. The authors report 24 cases of congenital supratentorial arachnoid cysts, 18 of which were studied with CT scanning; this method proved very valuable in pre- and postoperative assessment in all cases, and far superior to other diagnostic methods.
Spinal cord blood flow and conduction during experimental cord compression in normotensive and hypotensive dogs
Authors: Griffiths Ian R. , Trench James G. , Crawford Robert A.
Published: May 2009

✓ Spinal cord blood flow (SCBF) and dorsal column conduction, as assessed by the dorsal column evoked potential (DCEP), were measured during subacute cord compression in dogs. Ventral, midline balloons were used to produce compression and a dorsally situated strain gauge transducer measured the cord pressure. In normotensive animals there was autoregulation of SCBF to perfusion pressures (PP) of 65 to 70 mm Hg, and up to cord pressures of 55 to 60 mm Hg. The DCEP amplitude was significantly decreased even during this autoregulatory period. Conduction failure occurred at PP of 20 to 30 mm Hg. Chemically produced hypotension (74 mm Hg) did not affect either SCBF or DCEP. Minimal compression superimposed on hypotension decreased both flow and DCEP amplitude. The results indicate that ischemia is probably not the cause of the impaired conduction although, as the degree of compression increases, the cord will become ischemic once the autoregulatory limit is passed.
Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis
Authors: Steinbok Paul , Berry Kenneth , Dolman Clarisse L.
Published: May 2009

✓ Superficial temporal artery to middle cerebral artery (STA-MCA) anastomoses were examined at autopsy in two patients who survived 2 years and 5½ years, respectively, after the cerebral revascularization procedure. Identification of the actual anastomotic sites at autopsy was rendered impossible because of marked fibrosis in the region of the surgery. However, in both patients intimal fibrosis and medial damage were noted in the STA immediately adjacent to the anastomosis. In the patient who survived 2 years, the lumen of the STA was only slightly compromised by these changes, but in the patient who survived 5½ years, the artery was almost totally occluded. The MCA's adjacent to the anastomosis were widely patent and showed focal areas of intimal hyperplasia with no abnormalities of the media.
Failure of pyramidal tract decussation in the Dandy-Walker syndrome
Authors: Lagger Raymond L.
Published: May 2009

✓ The author describes non-decussation of the corticospinal tracts in two patients with the Dandy-Walker syndrome and multiple other congenital anomalies.
Swan-neck deformity secondary to osteomyelitis of the posterior elements of the cervical spine
Authors: Malik Ghaus M. , Crawford Alvin H. , Halter Robert
Published: May 2009

✓ A case of osteomyelitis is described, involving the posterior elements of the cervical vertebrae in a 7-year-old girl and resulting in swan-neck deformity. Treatment was initiated with antibiotics, and the patient was placed in halo traction. Eventually posterior cervical fusion was performed, which provided excellent stability and correction of the deformity.
Transsellar intracavernous intercarotid collateral artery associated with agenesis of the internal carotid artery
Authors: Staples Gary S.
Published: May 2009

✓ A 28-year-old woman with systemic lupus erythematosis was found to have a transsellar intracavernous intercarotid anastomosis with agenesis of the left internal carotid artery.
Cerebrovascular responses to subarachnoid blood and serotonin in the monkey
Authors: Boisvert Donald P. J. , Weir Bryce K. A. , Overton Thomas R. , Reiffenstein Rhoderick J. , Grace Michael G. A.
Published: May 2009

✓ Preliminary in vitro experiments were performed to determine the serum concentration of serotonin in the monkey, and the ability of cyproheptadine to block serotonin and serum-induced contractions in monkey cerebral arteries. Thirty-four cynomolgus monkeys were subsequently used to study changes in regional cerebral blood flow (CBF) obtained by the intracarotid 133Xe technique, and in the angiographic cerebral arterial caliber resulting from subarachnoid injection of artificial cerebrospinal fluid (CSF), blood, and serotonin. Five animals in each injection group were given 1.0 mg/kg intravenous cyproheptadine (a serotonin-blocking agent) during the post-injection period.

Subarachnoid injection of artificial CSF produced no change in CBF or arterial caliber. Post-injection administration of cyproheptadine also had no effect on these parameters. A subarachnoid injection of fresh autogenous blood produced a significant but transient (less than 1 hour) decrease in CBF and moderate vasospasm, which lasted at least 3 hours. This vasospasm was essentially unaffected by intravenous cyproheptadine. The CBF and arterial caliber were unchanged following a subarachnoid injection of serotonin at concentrations (5 × 10−6M) present in normal monkey serum. In contrast, 5 × 10−6 M serotonin invariably produced near maximal contractions in the in vitro cerebral artery preparations. Higher (× 10) serotonin concentrations caused a transient CBF response similar to that obtained with blood. However, the cerebral vasospasm induced was of shorter duration than that obtained with blood.

These results do not support a major role for serotonin in the production of post-subarachnoid hemorrhage vasospasm. Moreover, our data indicate that in vitro experiments do not reflect the ability of serotonin to constrict cerebral arteries in the intact animal.
Neurosurgical management of acromegaly
Authors: Laws Edward R. , Piepgras David G. , Randall Raymond V. , Abboud Charles F.
Published: May 2009

✓ A consecutive series of 82 acromegalic patients who underwent transsphenoidal surgery during a 5-year period is presented. Preoperative and postoperative values for human growth hormone (HGH) were available in 80 cases. Microadenomas were present in 18 patients with a mean preoperative HGH value of 25.2 ng/ml, diffuse adenomas in 39 patients with mean of 53.8 ng/ml, and invasive adenomas in 25 with mean of 68.0 ng/ml. There was no operative mortality. The results reflected the classification of the tumors, with apparent cures accomplished in 87.5% of previously untreated patients with microadenoma, all of whom had anterior pituitary function preserved. The percentages of apparent cures in cases of diffuse adenoma (68%) and invasive adenoma (54%) were much less satisfactory. Transsphenoidal microsurgery is capable of achieving good results, particularly in patients with microadenoma.
Metrizamide cisternography in the evaluation of pituitary adenomas and the empty sella syndrome
Authors: Gross Cordell E. , Binet Eugene F. , Esguerra Jorge V.
Published: May 2009

✓ Selected cases are presented demonstrating evaluation of sellar and juxtasellar pathology with metrizamide cisternography. The compatibility of metrizamide with the current generation of computerized tomography scanners has provided complementary data to metrizamide-enhanced hypocycloidal tomographic studies of the sellar and juxtasellar areas. The ease and low morbidity of metrizamide cisternography relative to pneumography is outlined.
Further data on the acute effect of intravenous steroids on canine CSF secretion and absorption
Authors: Vela A. Richard , Carey Michael E. , Thompson Bruce M.
Published: May 2009

✓ Considerable difference of opinion has arisen as to whether intravenously administered steroids affect cerebrospinal fluid (CSF) production in the acute laboratory animal undergoing ventriculocisternal perfusion. Our experiments with ventriculocisternal perfusion in dogs indicate that, when given intravenously, neither dexamethasone, methylprednisolone, hydrocortisone, nor aldosterone result in a significant, acute effect upon CSF production. Similarly, CSF absorption and outflow resistance mechanisms are not acutely affected by intravenous methylprednisolone, hydrocortisone, and aldosterone. Dexamethasone also probably does not produce an immediate effect upon CSF absorption.
Intracranial pressure and conductance to outflow of cerebrospinal fluid in normal-pressure hydrocephalus
Authors: Børgesen Svend Erik , Gjerris Flemming , Sørensen Søren Claus
Published: May 2009

✓ Forty patients with clinical evidence of normal-pressure hydrocephalus were studied by monitoring intraventricular pressure during a 24-hour period, and by a lumboventricular perfusion test for measurement of the conductance to outflow of cerebrospinal fluid (CSF). The purpose of the study was to investigate whether there is a relationship between intraventricular pressure and conductance to outflow of CSF, and whether it is possible to use the results from pressure monitoring in the selection of patients who may be expected to benefit from shunting therapy. The conductance to outflow was used as an evaluation factor in the selection of patients to be treated by a shunt.

The conductance to CSF outflow differed by twelvefold between the lowest and highest values. The level of resting intraventricular pressure was within normal limits in all patients. Accordingly, there was no evidence of a relationship between conductance to outflow and intraventricular pressure. So-called B-waves were seen more frequently in patients with decreased conductance to outflow, but were also present in patients with high conductance to outflow. Therefore, the presence of B-waves does not imply a low conductance to outflow of CSF.
Acromegaly with normal growth-hormone levels and pituitary histology
Authors: Feingold Kenneth R. , Goldfine Ira D. , Weinstein Philip R.
Published: May 2009

✓ In rare cases, acromegalic patients have normal basal concentrations of growth hormone, and their acromegaly results from abnormal growth-hormone secretory patterns. A patient is reported with the clinical features of acromegaly, who had elevated somatomedin levels and an enlarged sella turcica, but whose serum growth-hormone levels on continuous monitoring were in the normal range, with levels of 2.8 to 8.9 ng/ml. Dynamic studies of growth hormone revealed normal responses to hypo- and hyperglycemia, but abnormal responses to L-dopa and thyroid-releasing hormone. At surgery, neither a pituitary adenoma nor eosinophilic hyperplasia was present. It is likely that this patient's acromegaly resulted from the presence of chronically high normal levels of growth hormone.
Bilateral trigeminal and abducens neuropathies following low-velocity, crushing head injury
Authors: Summers C. Gail , Wirtschafter Jonathan D.
Published: May 2009

✓ A case is presented of bilateral injury to the trigeminal and abducens nerves following closed head trauma in which the patient survived crushing of the head by a heavy, large-diameter pipe. Bilateral trigeminal and unilateral abducens neuropathies persisted for more than 1 year. These unusual findings are discussed in regard to localization and possible mechanisms of injury. The effects of this type of low-velocity, crushing head injury are compared and contrasted with those of acceleration-deceleration head injuries.
Diagnosis and treatment of suprasellar arachnoid cyst
Authors: Murali Raj , Epstein Fred
Published: May 2009

✓ Three cases of suprasellar arachnoid cysts in children are described. The importance of differentiating such a lesion from a dilated third ventricle is stressed. The value of computerized tomography with Conray ventriculography in preoperative diagnosis, symptomatology, and choice of treatment are discussed.
Neurilemmoma of the fourth cranial nerve
Authors: Boggan James E. , Rosenblum Mark L. , Wilson Charles B.
Published: May 2009

✓ A tumor of the trochlear nerve sheath with an unusual but diagnostic presentation is described. The rarity of reported cases may reflect failure to differentiate tumors originating from the trochlear and trigeminal nerves.
Superficial temporal artery to middle cerebral artery anastomosis
Authors: Little John R. , Yamamoto Y. Lucas , Feindel William , Meyer Ernst , Hodge Charles P.
Published: May 2009

✓ Fluorescein angiography and xenon-133 (133Xe) clearance studies were performed during surgery on 15 patients who were undergoing superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis. Fourteen patients had occlusive disease of the internal carotid artery (ICA), and one patient had severe stenosis of the MCA. Before anastomosis, fluorescein angiography showed slow filling of the MCA branches through collateral channels. Focal areas of impaired microcirculatory filling and washout were seen in the territory of severely sclerotic cortical arteries. The findings of preanastomotic 133Xe clearance studies were variable and a uniform pattern of regional cerebral blood flow (rCBF) changes was not defined. In 55% of the patients, rCBF was reduced to 25 ml/100 gm/min or less at one or more detector sites. Fluorescein angiography provided an immediate assessment of anastomotic patency and clearly displayed the distribution of blood entering the epicerebral circulation through the STA. In 67% of patients, multiple MCA cortical branches filled with fluorescein, whereas in 33% filling was restricted to the receptor artery territory. An immediate, substantial (≥ 15 ml/100 gm/min) increase in rCBF was demonstrated in 73% of patients after anastomosis. The rCBF changes were consistently better in patients with donor and receptor arteries greater than 1 mm in diameter. Redistribution of collateral input acted to increase rCBF in areas distant from the anastomotic site. Some improvement in fluorescein circulation and rCBF also was seen in cortex supplied by sclerotic MCA branches.
Endothelial cell damage and thrombus formation following temporary arterial occlusion
Authors: Gertz S. David , Kurgan Adi , Wajnberg Rebecka S. , Nelson Erland
Published: May 2009

✓ The effects of restoration of blood flow on endothelial damage that occurs distal to the site of temporary arterial occlusion with surgical clips, and the effects of heparin and aspirin on thrombus formation at the site of the clip, were studied by scanning electron microscopy (SEM). The right carotid artery of 45 rabbits was occluded with a Heifetz clip for 30 minutes. The clips were then removed and blood flow resumed for periods of 30 minutes, 1 hour, 2 hours, and 24 hours. A second group was preteated intravenously with heparin (1400 units/kg), and a third group was pretreated orally with aspirin (50 mg/kg). The SEM analysis of arterial segments distal and proximal to the clip indicated that the frequency of occurrence of endothelial crater- and balloon-like vesicular defects decreased to zero within 24 hours of restoration of blood flow. Examination of arterial segments compressed by the clip revealed endothelial desquamation and thrombus formation within 30 minutes of resumption of flow. The maximum degree of thrombus formation occurred within 1 to 2 hours of resumption of flow, with a subsequent decrease in the extent of deposition of platelets, fibrin, erythrocytes, and leukocytes within 24 hours. No change was found in composition or quantity of thrombus formation after pretreatment with heparin although, in the latter specimens, fibrin deposition appeared considerably less. However, pretreatment with aspirin resulted in marked reduction in the overall quantity of thrombus formation at the site of the clip following temporary occlusion.
Regional cerebral blood flow in patients with ruptured intracranial aneurysms
Authors: Ishii Ryoji
Published: May 2009

✓ Eighty-five studies of regional cerebral blood flow (rCBF) were performed on 49 patients with ruptured intracranial aneurysms. The changes in rCBF were analyzed under various pathophysiological conditions. The degree of flow abnormalities correlated well with the clinical severity of neurological deficits. All of the patients with diffuse vasospasm of severe grade, to less than half of their control value, showed focal areas of decreased flow below 30 ml/100 gm/min, in addition to a reduction in mean CBF. The relief or disappearance of vasospasm in angiograms was followed by the increase of rCBF in the ischemic focus and mean CBF. Marked reduction in rCBF was found in patients with intracerebral hematoma and ventricular dilatation. Impaired CO2 response and autoregulation were found in patients with severe neurological deficits, a severe degree of vasospasm and marked depression of mean CBF. In this series direct operation was delayed in patients with impaired vascular reactivity as well as marked decrease of mean CBF below 30 ml/100 gm/min; good clinical results were obtained in these patients.
Halo immobilization of cervical spine fractures
Authors: Cooper Paul R. , Maravilla Kenneth R. , Sklar Frederick H. , Moody Sarah F. , Clark W. Kemp
Published: May 2009

✓ Thirty-three patients with a spectrum of cervical spine fractures or subluxations were treated with immobilization by a halo apparatus. All spines were assumed to be unstable because of the nature of the fracture or because of a subluxation noted on spine films. Treatment consisted of immobilization and fracture reduction followed by application of a halo plaster cast or molded halo plastic vest. Patient acceptance was high. Complications were few and minor. No patient experienced neurological deterioration during treatment. Reduction was well maintained during an average halo immobilization period of over 3 months. Use of the halo resulted in healing of bone and ligament and restoration of stability in 85% of the patients. Halo immobilization was efficacious in the treatment of odontoid and hangman's fractures as well as complex fractures involving multiple areas of a single vertebra. It was also used successfully as an adjunct to posterior cervical fusion. Although several patients with subluxations or angulation without bone injury were treated successfully, two of the four therapy failures occurred in this group of patients, and the halo must be used with caution in this clinical setting. Contraindications to the use of the halo include complete cervical spinal cord injury with anesthetic skin, tomographic and/or myelographic evidence of disc or bone within the spinal canal, and unsatisfactorily reduced subluxations. The halo has provided more effective and reliable immobilization than other orthoses. It is an acceptable alternative to cervical fusion for the achievement of stability in a wide variety of cervical spine fractures and dislocations avoiding both the short-term and perhaps long-term complications of spinal fusion.
Evaluation of malignant glioma patients during the postirradiation period
Authors: Hoffman William F. , Levin Victor A. , Wilson Charles B.
Published: May 2009

✓ The syndrome of increased focal or generalized central nervous system (CNS) dysfunction in the early postirradiation period in patients treated with radiation therapy (RT) for malignant gliomas has not been well documented. The authors have undertaken retrospective study of 51 patients with supratentorial malignant gliomas who survived longer than 26 weeks from the time of diagnosis. All patients received irradiation and chemotherapy and were evaluated at 8-week intervals. Each evaluation consisted of a neurological examination, computerized tomography (CT) and radionuclide scans, Karnofsky rating, and an evaluation of glucocorticoid levels needed to maintain neurological function. In all, 263 evaluable periods, consisting of 1290 individual evaluable tests (parameters), were analyzed. In the first 18 weeks after RT, 26 of the 51 patients studied (51%) showed deterioration in one or more tests; 14 of the 26 (53%) did not improve. These 14 patients had a median time to tumor progression (MTP) of 31 weeks. The remaining 12 patients in this group (47%) improved and had an MTP of 73 weeks. Of the 51 patients, 25 (49%) showed deterioration significant enough to presume tumor progression (two of the following three tests were unequivocally worse: neurological examination, CT scan, and radionuclide scan), seven improved with no change in therapy and had an MTP of 66 weeks, while the other 18 had an MTP of 32 weeks. Excluding the Karnofsky rating, any individual test that showed worsening during the first 18-week period had a 33% probability of significant improvement at a subsequent evaluation period. After 18 weeks the probability of the test improving was only 4%.

The authors conclude that CNS decompensation up to 18 weeks after RT, as ascertained from clinical examination, scans, or glucocorticoid dosage, does not invariably predict tumor progression, because in 28% (7/25) of such cases there will be subsequent improvement.
The effects of ischemia on long-tract neural conduction in the spinal cord
Authors: Kobrine Arthur I. , Evans Delbert E. , Rizzoli Hugo V.
Published: May 2009

✓ In this experiment, the effects of ischemia on neural conduction in the monkey spinal cord were studied. In six monkeys generalized ischemia of the spinal cord was created by bleeding the animals to a hypotensive level below the lower limits of autoregulation in the spinal cord. The progressive development of spinal cord ischemia was documented by blood-flow measurement using the hydrogen clearance method. Physiological integrity of the spinal cord was monitored and recorded by the spinal evoked response. The spinal evoked response did not disappear until at least 10 minutes of profound ischemia. At levels of ischemia 20% to 25% of normal blood flow, the spinal evoked response was unchanged. It is concluded that long-tract neural conduction in the spinal cord is relatively resistant to the effects of ischemia.
Simultaneous clinical manifestation of subependymoma of the fourth ventricle in identical twins
Authors: Clarenbach Peter , Kleihues Paul , Metzel Eberhard , Dichgans Johannes
Published: May 2009

✓ At the age of 22 years, identical twin brothers simultaneously developed symptoms of intracranial pressure. Radiological investigation revealed cerebellar midline tumors with occlusive hydrocephalus of the third and lateral ventricles. At operation, subependymomas with identical histological features were found in the fourth ventricle in both twins. This is the first report of subependymomas in identical twins. The clinical data suggest that this tumor type is of maldevelopmental origin.
Transient hemiparesis: A rare manifestation of diphenylhydantoin toxicity
Authors: Findler Gideon , Lavy Sylvan
Published: May 2009

✓ Among the common side effects of diphenylhydantoin (DPH) overdose, the most frequently encountered neurological signs are those of cerebellar dysfunction. Very rarely, the toxic neurological manifestations of this drug are of cerebral origin. Two patients are presented who suffered progressive hemiparesis due to DPH overdose. Both had brain surgery before DPH treatment. It is assumed that patients with some cerebral damage are liable to manifest DPH toxicity as focal neurological signs.
The physiopathology of respiration in neurosurgical patients
Authors: Frost Elizabeth A. M.
Published: May 2009

✓ Regulation of respiration is summarized as to peripheral and central chemoreceptors, controllers of voluntary and automatic respiration, and stimulators (CO2, O2, and pH). The information that may be obtained from blood-gas analysis is reviewed and basic problems in acid-base imbalance described. Commonly employed respiratory patterns are discussed.

Preoperative pulmonary assessment necessary in elective intracranial situations, spinal cord injuries, and pediatric neurosurgery is outlined. Some of the special problems of the patient with multiple trauma, including injury to the central nervous system are reviewed. Central and peripheral factors that cause respiratory difficulty in head-injured patients are tabulated, and an outline is given of diagnosis and therapy. There are many possible causes of intraoperative hypoxia and hypercarbia, and these complications with their prevention or treatment are examined. Criteria for extubation are established. Finally, postoperative pulmonary care in elective, emergency, and cord injury situations is discussed. The key to successful perioperative pulmonary care of the neurosurgical patient requires close cooperation between the neurosurgeon and anesthesiologist.
A computerized tomography-computer graphics approach to stereotaxic localization
Authors: Brown Russell A.
Published: May 2009

✓ This paper describes the use of three-dimensional computer graphics to display structures visible in computerized tomography (CT) scans and to accurately determine optimum stereotaxic probe placement relative to those structures. A prototype Lucite stereotaxic frame designed for use in CT body scanners was fitted with a phantom consisting of small Lucite spheres representing intracranial tumors with diameters of 6 to 19 mm. A series of CT scans was obtained of the frame and phantom together. Edge outlines of the spheres were extracted from each scan in the series. A three-dimensional visual representation of the spheres was obtained by displaying their outlines from all CT scans. A superimposed visual simulation of the stereotaxic frame was adjusted interactively using several analog dials in order to simulate trajectory choice and probe depth before actual surgery. The frame settings and probe depth calculated by the graphical computer were then applied to the actual prototype frame in order to assess the accuracy of this combined CT-computer graphics approach to stereotaxic localization. The results of 22 such experiments and the implications for future clinical use of this new and precise localization technique are discussed.
Reconstitution of “totally” occluded internal carotid arteries
Authors: Countee Roger W. , Vijayanathan Thurairasah
Published: May 2009

✓ The authors describe their experiences with five patients with delayed transient ischemic symptoms homolateral to internal carotid artery (ICA) occlusions. In each instance, initial arteriograms were interpreted as showing irreversible occlusions of these arteries in the neck and microvascular bypass procedures were contemplated. However, after repeat arteriographic evaluations with a modified injection technique, certain angiographic features were identified that suggested the mechanism of the symptoms in these patients and that their ICA's could be reconstituted in the neck. This was successfully accomplished in each patient with complete relief of ischemic symptoms. The angiographic technique employed and the arterial flow patterns identified in these patients are discussed. The details of the operative technique are described. It is concluded that routine arteriographic techniques may be inadequate to identify the reversible carotid occlusion. This may account for some of the confusion which surrounds the surgery of these vessels as well as the failure of extracranial-intracranial bypass to relieve recurrent ischemic symptoms in these individuals.
Pulmonary shunt as a prognostic indicator in head injury
Authors: Frost Elizabeth A. M. , Arancibia Carlos U. , Shulman Kenneth
Published: May 2009

✓ Severe head injury may cause momentary respiratory arrest. Resultant hypoxia would increase cerebral edema and adversely affect the quality of survival. This study examines the effect of hypoxemia on outcome. Pulmonary shunt was calculated as a convenient measurement of respiratory insufficiency in 86 severely head-injured patients who underwent surgery. All samples were taken shortly after induction into anesthesia when controlled ventilation with high inspired-oxygen concentration had been established. In 39 patients who improved, mean pulmonary shunt was 8.9%. Twelve patients who survived with deficit showed a mean shunt of 13.6%, and in 35 patients who died, the mean initial shunt was 15.6%. No significant correlation was found between abnormal chest x-ray findings or the occurrence of hypertension and shunt percentage. The American Society of Anesthesiologists at-risk classification correlated grossly with the outcome.

Early pulmonary shunt is a prognostic indicator in severe head injury and should be used in conjunction with the Glasgow Coma Scale in assessing outcome. Despite an apparently adequate respiratory pattern, all patients with severe head injury must be assumed to be hypoxic until proven otherwise. While hypoxemia may prove to be refractory in overwhelming injury, patients who score low on the Glasgow Coma Scale but who have relatively normal oxygen exchange may still survive with little deficit.
Middle meningeal to middle cerebral arterial bypass for cerebral revascularization
Authors: Miller Clinton F. , Spetzler Robert F. , Kopaniky Dennis J.
Published: May 2009

✓ A case is reported of successful anastomosis of the middle meningeal artery to a cortical branch of the middle cerebral artery. Based on the analyses of 50 random angiograms, the authors discuss the circumstances in which such an anastomosis might be practical and indicated.
Multiple intramedullary neurinomas of the spinal cord
Authors: Pardatscher Kurt , Iraci Giorgio , Cappellotto Paolo , Rigobello Luca , Pellone Mario , Fiore Daniele
Published: May 2009

✓ A case of multiple neurinomas, firmly embedded within the nervous substance of the spinal cord and presumably extending over the entire length of its surface, is reported. The complete lack of relationship of the multiple lesions with the spinal roots and the absence of signs of neurofibromatosis are the most salient features of this uncommon case. In a discussion on the origin of the condition, it is concluded that this case might be an example of neurocristopathy.
Randomized clinical trials in the evaluation of surgical innovation
Authors: Haines Stephen J.
Published: May 2009

✓ Randomized clinical trials are widely accepted as the standard for evaluation of therapeutic innovation in many fields of medicine. The three basic components of such trials (concurrent comparison, random allocation, and objective observation) are designed to control four forms of bias (chronology bias, susceptibility bias, compliance bias, and observation bias) that may interfere with the interpretation of the results of a study. Only 2% of the articles evaluating therapeutic maneuvers published in the Journal of Neurosurgery have attempted to use concurrent controls. Only one of 863 such articles met the criteria for a randomized clinical trial. Reasons for underutilization of such trials in neurosurgery are discussed and suggestions for their wider use are offered.
Relative cerebral glucose metabolism evoked by dental-pulp stimulation in the rat
Authors: Shetter Andrew G. , Sweet William H.
Published: May 2009

✓ Electrical stimulation of dental pulp is widely acknowledged to produce a sensation that is predominantly or exclusively noxious in character. The authors report the pattern of local cerebral glucose utilization evoked by dental-pulp stimulation in the barbiturate-anesthetized rat, using the [14C]2-deoxyglucose method of Sokoloff. Autoradiographs were prepared from cryostat-cut brain sections of animals given an intravenous pulse of [14C]2-deoxyglucose and sacrificed after 45 minutes of continuous bipolar stimulation of the incisor tooth pulp. Areas of high optical density on the autoradiographs identified brain regions where glucose consumption, and hence functional activity, was maximal. Stimulus-related increases in glucose utilization were seen ipsilaterally in an uninterrupted column from the lower levels of trigeminal nucleus caudalis to the rostral extent of the main sensory nucleus. Mandibular incisor pulp stimulation yielded increased deoxyglucose uptake in relatively restricted dorsal portions of the nuclei, while maxillary pulp stimulation produced a more extensive area of uptake ventrally. Elevated deoxyglucose uptake was also seen in the contralateral ventrobasal thalamus and sensory cortex with maxillary, but not mandibular, pulp stimulation. No changes in metabolic activity were detected in extralemniscal or limbic structures. These initial results suggest that the [14C]2-deoxyglucose method may be a useful means of mapping central structures involved in nociception.
The effects of graded experimental trauma on cerebral blood flow and responsiveness to CO2
Authors: Saunders Myles L. , Miller J. Douglas , Stablein Donald , Allen Gilbert
Published: May 2009

✓ The effects of graded mechanical cerebral trauma on cerebrovascular reactivity to CO2 was studied in 26 cats. A fluid-wave percussion model was employed which delivered an epidural trauma of fixed duration and variable amplitude. The animals were maintained at arterial normoxia, with constant monitoring of intracranial and systemic arterial pressures, electroencephalograms, and end-tidal CO2. Following trauma, cerebral blood flow was measured using the H2 ion clearance technique at PaCO2 levels ranging sequentially from 20 to 60 mm Hg. Cerebrovascular reactivity for control animals (uninjured) was 2.7%. In the group with mild trauma (0.76 to 1.90 atm) reactivity was impaired (1.7%), and it was abolished in the severely injured group (2.90 to 4.60 atm). Mild injuries did not alter resting blood flows, while severe trauma resulted in a significant decrease in cerebrovascular resistance. Intracranial and systemic arterial pressures were altered proportionately to the level of cerebral injury. The authors propose that trauma to the brain-stem vasoregulatory centers accounts for these findings.
Intracranial aneurysms
Authors: Andrews Russell J. , Spiegel Peter K.
Published: May 2009

✓ All cases of intracranial aneurysm, arteriovenous malformation, and subarachnoid hemorrhage of undetermined etiology seen at one hospital over a 13-year period were reviewed to assess relationships between age, sex, systolic and diastolic blood pressure, and number of aneurysms. There were 350 patients, of whom 212 had aneurysms. The major findings were as follows: 1) Hypertension was not significantly more prevalent in the aneurysm population than in the age-matched general population, except for females aged 18 to 54 years (systolic pressure elevation of 10 to 15 mm Hg). 2) Under 55 years of age, both male and female hypertensive patients were twice as likely to have multiple aneurysms as normotensive patients. 3) Females were more likely than males to have multiple aneurysms. 4) For females but not males, increasing age, higher systolic pressure, and higher diastolic pressure all correlated with an increasing number of aneurysms.

Hypertension appears to be more prevalent in certain subgroups of the total aneurysm population, although the individual relationships between hypertension, atherosclerosis, and aneurysms cannot be determined from either the present or previous studies. The possible role of familial factors, as well as implications for both diagnosis and further research, are briefly noted.
Capillary ultrastructure in human metastatic brain tumors
Authors: Long Don M.
Published: May 2009

✓ The ultrastructural characteristics of blood vessels within 18 metastatic neoplasms of the brain have been studied. The abnormal permeability to protein-bound tracers was found to be related to defective capillary endothelium. Abnormalities include gap functions, fenestrations of membranes, and open normal junctions. The abnormal capillaries had the character of capillaries from current tissue. Endothelium cell abnormalities were not found in surrounding edematous brain.
Dorsal root entry zone lesions for pain relief
Authors: Nashold Blaine S. , Ostdahl Roger H.
Published: May 2009

✓ Arm pain due to avulsion of the cervical dorsal roots of the brachial plexus may become intractable, ameliorated little, if at all, by contemporary medical or surgical treatment. Severe and sudden trauma to the neck, shoulder, or arm is the usual cause of avulsion of the cervical rootlets. The injury may result in complete sensorimotor paralysis of the involved extremity, or a partial deficit if only a few rootlets are involved. Previous therapies have included stellate block, sympathectomy, high cervical cordotomy, rhizotomy, transcutaneous stimulation, dorsal column stimulation, mesencephalic tractotomy, cingulotomy, and the use of narcotics. The extent of the pathological change in the spinal cord following root avulsion is not completely known; at the time of operation, abnormalities frequently noted included ipsilateral atrophy of the dorsal aspect of the cord, dense arachnoid scarring, microcyst formation, and loss of both dorsal and ventral roots. The cervical myelogram is abnormal, although not necessarily pathognomonic of the extent of injury. The surgical technique of coagulation of the dorsal root entry zone is discussed, and the results and morbidity in 21 patients are reviewed. Thirteen patients (67%) continue to have good pain relief, with follow-up periods ranging from 6 months to 3½ years. Three patients with extremity pain from other causes are included in the series. Clinical observations suggest the possibility that pain resulting from brachial plexus avulsion originates from pathophysiological changes in the injured dorsal horn of the spinal cord. This report is a discussion of a new technique aimed at destruction of the dorsal root entry zone for relief of chronic extremity pain.
Influence of hypoxia on the composition of isolated edema fluid in cold-induced brain edema
Authors: Go K. Gwan , Gazendam Jurjen , van Zanten Annie K.
Published: May 2009

✓ The isolation of edema fluid from cats with cold-induced cerebral edema allowed the study of changes of Na+ and K+ content, lactate dehydrogenase and creatine phosphokinase activity, colloid osmotic pressure and the level of intravenously administered 99mTc-albumin in the edema fluid during a period of hypoxia. The changes consisted of an increase of all mentioned parameters, except Na+; and could be interpreted as a concentration of solutes (but for Na+) in the extracellular edema fluid, concomitant to a reduction of the extracellular space, as the oxygen deficiency caused improper functioning of the cellular Na+-K+ pump, with a resulting shift of fluid (including Na+) into the cellular elements.
Relation of age and cerebral ventricle size to central canal in man
Authors: Kasantikul Vira , Netsky Martin G. , James A. Everette
Published: May 2009

✓ The central canal of the spinal cord in man with and without hydrocephalus was studied histologically. The lumen was patent in most patients in the first two decades of life. Cells lining the canal in the prenatal and newborn state and in the first decade of life were predominantly pseudostratified ciliated epithelium. In the second decade, the epithelium became simple columnar or cuboidal. The central canal closed in most cases after the age of 20 years, secondary to proliferation of ependymal cells and astrocytes. Mechanisms whereby the number of glial cells increase are considered. The canal was closed in all adults with normal ventricular size, and in 94% of persons with various degrees of hydrocephalus. In the remaining 6% of cases with hydrocephalus, the lining of the canal resembled that seen in the first two decades, and could have acted as a pathway of cerebrospinal fluid (CSF) absorption. Three cases of severe hydrocephalus in the first two decades of life were encountered; the central canal was patent in one, and occluded in two. Based on these data, the canal was not a significant pathway of CSF absorption in most instances of hydrocephalus and in persons with dilated ventricles who were older than 20 years of age.
Recurrent transient ischemic attacks secondary to an embolizing saccular middle cerebral artery aneurysm
Authors: Hoffman William F. , Wilson Charles B. , Townsend Jeannette J.
Published: May 2009

✓ Over a 1-year period, a 60-year-old woman had nine episodes of transient weakness, clumsiness, and hypesthesia of the right upper extremity. Angiography revealed normal extracranial vessels and a left middle cerebral artery aneurysm. The aneurysmal sac, removed at operation, had an organized thrombus, which was believed to be the cause of the transient ischemic attacks. Postoperatively, the patient has remained free of neurological symptoms.
Cyanoacrylate occlusion of a spinal cord arteriovenous malformation
Authors: Margolis M. Theodore , Freeny Patrick C. , Kendrick Michael M.
Published: May 2009

✓ An arteriovenous malformation of the spinal cord was successfully obliterated by a percutaneous transcatheter technique using isobutyl 2-cyanoacrylate.
Empty sella secondary to suprasellar colloid cyst of foregut (respiratory) origin
Authors: Evans Dwight C. , Netsky Martin G. , Allen Verne E. , Kasantikul Vira
Published: May 2009

✓ An enlarged sella turcica was discovered in a 40-year-old man who had bitemporal headaches. A pneumoencephalograph revealed a third ventricular cyst, dilated lateral ventricles, and an empty sella. The colloid cyst was lined by foregut epithelium, probably originating in the respiratory tract, and dense connective tissue. This case is the first instance of an empty sella associated with a colloid cyst of the third ventricle. It is proposed that enlargement of the mass in the third ventricle caused increased pulsation pressure of the cerebrospinal fluid, and that in the presence of an incompetent diaphragma sellae the subarachnoid space expanded into the sella. The origin of third ventricle cysts is reconsidered. It is concluded that suprasellar colloid cysts may arise from endoderm, ectoderm, neuroepithelium, or a combination of these epithelia.