bluuebunny/crossref_metadata_2025 huggingface dataset:
A fast method of estimating the elastance of the intracranial system
Authors: Szewczykowski Jerzy , liwka Stanislaw , Kunicki Adam , Dytko Pawel , Korsak-liwka Jolanta
Published: May 2009

✓ The authors describe a fast method for estimating the elastance of the intracranial system in man. The method consists in constructing the so-called amplitude-pressure (Amp-P) curve which describes the relationship between the amplitude of pulse-related oscillations in cerebrospinal fluid pressure and the basic level of intracranial pressure. The Amp-P curve consists of two straight lines, and the point of intersection of these lines is thought to indicate the intracranial pressure level at which there occurs a qualitative change in the functioning of compensatory mechanisms of the intracranial system. The authors applied the method to examine the Amp-P curves of 10 patients without intracranial pathology and found that they provide a good description of the state and dynamics of the intracranial system. Preliminary data obtained in patients with intracranial pathology indicate that the method is a valuable tool in the diagnosis and treatment of neurosurgical patients.
Prognosis of seventh nerve palsy following removal of large acoustic tumors
Authors: Erickson Donald L. , Ausman James I. , Chou Shelley N.
Published: May 2009

✓ Before the advent of microsurgery for acoustic tumors, it was accepted that the majority of seventh nerves would be lost during the removal of large tumors. It is now possible to preserve these attenuated seventh nerves, even with very large tumors. Postoperative facial palsy may be present even with an anatomically intact seventh nerve, but our experience has demonstrated that recovery will ultimately occur. Eight of our nine patients with this situation have regained facial function, although in some the first clinical evidence of recovery did not occur for 1 year.
Immunobiology of primary intracranial tumors
Authors: Mahaley M. Stephen , Gentry Robert E. , Bigner Darell D.
Published: May 2009

✓ The avian sarcoma virus-induced glioma model in rats was used to study the effectiveness of immunotherapy, namely, Bacillus Calmette-Guérin (BCG) with or without sarcoma cells and/or chemotherapy with 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU), upon survival times. The most consistent prolongation of survival time was produced by triple therapy: BCG + intraperitoneally administered sarcoma cells + intravenously administered BCNU.
Cerebral perfusion, vascular spasm, and outcome in patients with ruptured intracranial aneurysms
Authors: Kelly Patrick J. , Gorten Ralph J. , Grossman Robert G. , Eisenberg Howard M.
Published: May 2009

✓ In a retrospective study of 44 patients with verified ruptured intracranial aneurysms, the results of radionuclide cerebral perfusion scintigraphy (dynamic brain scanning) and the presence or absence of arteriographic spasm were correlated with the clinical outcome. The data indicated that patients with normal dynamic scans had a better outcome as a group and following intracranial surgery than those in whom perfusion was reduced. Patients with normal perfusion had a higher incidence of preoperative rebleeding from their aneurysms, while patients with reduced perfusion had a higher incidence of infarction, especially after intracranial surgery. There was no correlation between the presence or absence of arteriographic spasm and the results of the dynamic scans, and no correlation between the presence or absence of spasm and the outcome of the group as a whole. However, in some individual cases with severe spasm, reduced perfusion on the dynamic scan and a poor outcome were noted. It was concluded that the results of the dynamic scan correlated better with eventual patient outcome than the presence or absence of arteriographic spasm. It is therefore suggested that patients in Grades I and II with normal dynamic scans be operated on promptly to prevent rebleeding, and that surgery in patients in Grades I and II with abnormal dynamic scans be delayed until the dynamic scan returns to normal.
Absence of vasospastic response of the anterior spinal artery to subarachnoid blood
Authors: Doppman John L. , Girton Mary
Published: May 2009

✓ Autologous blood (0.3 to 5.0 ml) was introduced into the lumbar subarachnoid space of nine monkeys. Serial spinal cord arteriography was performed at frequent intervals over a 24-hour period. Magnification techniques permitted direct measurement of the anterior spinal artery and posterior spinal vein. Neither immediate nor delayed spasm was observed in any animal. Similar techniques have routinely produced spasm of intracranial arteries in our laboratory.
Computerized tomography and surgical treatment in intracranial suppuration
Authors: Joubert Mauritius J. , Stephanov Stephan
Published: May 2009

✓ The authors report their experience with 30 cases of intracranial suppuration: 23 with brain abscess and seven with subdural empyema. All of the cases were diagnosed by means of computerized tomography and enhancement with intravenous contrast material. Most of the patients were treated by single or repeated aspiration through burr holes.
Ventriculolymphatic shunt
Authors: Kempe Ludwig G. , Blaylock Russell
Published: May 2009

✓ The authors report the cases of 16 adult patients who underwent ventriculolymphatic shunt procedures with apparent good results. The follow-up period is from 2 to 12 years. The anatomy of the terminal portion of the thoracic duct studied in 51 patients undergoing sympathectomy of the lower cervical-upper thoracic ganglionic chain is reported. The operative technique of the ventriculothoracic duct shunting procedure is described, and a general review of the function of the shunt as compared with that of ventriculoatrial shunts is presented.
Human chorionic gonadotropin produced by ectopic pinealoma in a girl with precocious puberty
Authors: Kubo Osami , Yamasaki Naomi , Kamijo Yasuo , Amano Keiichi , Kitamura Koichi , Demura Reiko
Published: May 2009

✓ A case is reported in which a human chorionic gonadotropin (HCG)-producing ectopic pinealoma was found in a 5-year-old girl with precocious puberty. Physical examination revealed abnormal breast enlargement. Endocrinological study disclosed a high plasma HCG concentration of 1192 ng/ml with a normal follicular stimulating hormone (FSH) level. The HCG content of the tumor was as high as 400 ng/mg of acetone dried tissue, but no FSH was detectable. This is the first reported case of precocious puberty associated with pineal tumor in a female.
Sarcoid of the cauda equina
Authors: Campbell James N. , Black Perry , Ostrow Peter T.
Published: May 2009

✓ An unusual case of sarcoid involving the cauda equina, resulting in progressive paraparesis, is presented. There was no evidence of sarcoid involvement outside the nervous system, and the diagnosis was established through thoracolumbar exploration. The patient was treated with steroids postoperatively, and had a moderate recovery of neurological function.
Anomalous course of the recurrent motor branch of the median nerve in a patient with carpal tunnel syndrome
Authors: Werschkul J. Douglas
Published: May 2009

✓ A case is discussed in which carpal tunnel syndrome with an unusual course of the motor recurrent branch was discovered at operation. The importance of a careful dissection of the median nerve in this condition is emphasized.
Iron-acrylic compound for stereotaxic aneurysm thrombosis
Authors: Alksne John F. , Smith Randall W.
Published: May 2009

✓ A new iron-acrylic compound has been developed for stereotaxic thrombosis of intracranial aneurysms. The compound polymerizes rapidly, does not fragment, and is nontoxic. It has been used in a series of experimental animals and in initial clinical cases with good results. The use of this material simplifies and increases the safety of stereotaxic aneurysm treatment.
Microsurgical treatment of internal carotid artery aneurysms
Authors: Hollin Sidney A. , Decker Robert E.
Published: May 2009

✓ Seventy consecutive cases of internal carotid artery aneurysm were operated on utilizing the surgical microscope. There were three deaths (4.3% mortality), one of which occurred in a deeply comatose apneic patient. Fifty-nine patients (84%) had excellent results. Four (6%) had postoperative morbidity directly related to their operation; three of them were operated on within 2 weeks after subarachnoid hemorrhage and had neurological deficits attributed to cerebrovascular spasm. The low morbidity and mortality rates are partially related to patient selection but also significantly influenced by improved surgical techniques made possible by the microscope and microsurgical instrumentation. It is the authors' opinion that microsurgery should be standard procedure for craniotomy for intracranial aneurysm. It is suggested that future reported series of aneurysm therapy, regardless of the method of treatment employed, should be compared with the anticipated natural history.
Evaluation of brain function in severe human head trauma with multimodality evoked potentials
Authors: Greenberg Richard P. , Becker Donald P. , Miller J. Douglas , Mayer David J.
Published: May 2009

✓ Electrophysiological investigations were undertaken in 51 comatose patients with severe head trauma to locate areas of brain dysfunction and to relate the loci of dysfunction to the patient's posttraumatic neurological condition. On the basis of evoked potential data, the presence of decortication or decerebration depended on cerebral hemispheric dysfunction. Brain-stem dysfunction, defined by evoked potentials, did not correlate with posturing. On the other hand, impaired oculocephalic responses and bilateral abnormal pupillary light responses were associated with brainstem dysfunction, while hemispheric dysfunction did not correlate with either: Duration of coma was dependent on hemispheric dysfunction. Brain-stem dysfunction was not significantly associated with prolonged coma. Furthermore, 80% of the head trauma patients who had Grade I or II multimodality evoked brain-injury potentials recorded in the acute period following head trauma (mean Day 3) became responsive within 30 days of their injury. Graded somatosensory brain injury potentials appeared to be a powerful prognostic tool as they significantly correlated with the patient's final outcome even when recorded early after injury. Abnormal multimodality evoked potentials recorded acutely consistently defined dysfunction of the visual, auditory, and motor systems in comatose patients, and were considerably more effective than the clinical neurological examination in diagnosing persisting focal deficits of these systems.
Pain reduction by electrical brain stimulation in man
Authors: Richardson Donald E. , Akil Huda
Published: May 2009

✓ Acute studies performed in five patients indicate that electrical stimulation of the brain could be a powerful tool for the reduction or control of intractable pain. While chronic or spontaneous pain could be relieved by stimulation of the periaqueductal gray matter, the accompanying side effects render it impossible to stimulate this site regularly. On the other hand, stimulation of medial thalamic sites, particularly medial to the nucleus parafascicularis, yielded good relief of chronic pain at parameters which did not cause many undesirable side effects. The same parameters also produced inhibition of acute pain in two of the five patients.
Effects of positive end-expiratory pressure on intracranial pressure and compliance in brain-injured patients
Authors: Frost Elizabeth A. M.
Published: May 2009

✓ Hypoxic pulmonary disorders and head injuries associated with increased intracranial pressure (ICP) frequently co-exist. Positive end-expiratory pressure (PEEP) improves hypoxemia but has been reported to impede cerebral venous return, potentially causing a further increase in ICP. This study examined the effects of PEEP on ICP at different levels of brain compliance.

Continuous ICP recordings were obtained after insertion of Scott cannulas to the lateral ventricles of seven comatose patients. Brain compliance was assessed by calculation of the pressure volume index. Patients were maintained in a 30° head-up position. Maintenance of PEEP to levels of 40 cm H2O pressure for as long as 18 hours did not increase ICP in patients with either normal or low intracranial compliance, and did not increase ICP in the absence of pulmonary disease. Central venous pressure and pulmonary artery wedge pressure increased proportionately as PEEP was increased. No consistent changes were found in blood pressure recordings, nor were there any reductions in cardiac output found during the studies. Abrupt discontinuation of PEEP did not result in increased ICP except for a transient rise on two occasions when respiratory secretions became copious and the patients were inadequately ventilated. Improved oxygenation in two patients as a result of PEEP was concomitant with improved intracranial compliance and neurological status.

In patients with brain injuries, PEEP improves arterial oxygenation without increasing ICP as previously supposed. Consequently, PEEP is a valuable form of therapy for the comatose patient with pulmonary disorders such as pneumonia or pulmonary edema.
An audible alarm for monitoring air embolism during neurosurgery
Authors: Brechner Theresa M. , Brechner Verne L.
Published: May 2009

✓ The sensitivity of various monitors during experimental pulmonary air embolization was measured in five dogs. Changes in vital signs, electrocardiogram, Doppler sound, and end tidal CO2 were observed. An audible alarm was incorporated in the end tidal CO2 monitor. The results showed that a 0.01 cc to 0.02 cc/kg dose of air triggered the Doppler consistently, but the changes in heart sounds were heard only transiently. The fall in end tidal CO2 occurred at 0.5 to 1.0 cc/kg of intravenously injected air and was confirmed by pen write-out. The audible alarm device was constructed to sound after four consecutive breaths with preset percentage fall in end tidal CO2. The changes in vital signs occurred at doses of 4 to 8 cc/kg of air and death occurred at 8 to 10 cc/kg.

The sound alarm was used in 30 patients during sitting craniotomies. Eight patients developed air emboli initially detected by transient change in Doppler sound. The alarm called attention to the fall in end tidal CO2 and confirmed the occurrence of air emboli.
Toxicity kinetics and clinical potential of subarachnoid lymphocyte infusions
Authors: Neuwelt Edward , Doherty Dennis
Published: May 2009

✓ The feasibility of intrathecal lymphocyte infusions was examined since patients with gliomas are known to have circulating, tumor-specific, cytotoxic lymphocytes. Human (xenogenic) and syngenic lymphocytes were infused intrathecally into rabbits, and the toxicity and kinetics of the infused cells evaluated. Cerebrospinal fluid cell counts rose to as high as 70,000 lymphocytes/cu mm 12 hours after infusion and then dropped logarithmically over several days. No infiltration of host cells into the subarachnoid space in response to the lymphocyte infusions was detected. Evidence is presented that intrathecally infused lymphocytes may escape into the systemic circulation. Toxicity was minimal, especially following syngenic intrathecal lymphocyte infusions. A systemic allergic response, characterized by choroid plexitis and pulmonary edema was noted following a second xenogenic but not after a second or even a third syngenic lymphocyte infusion.
Management of craniopharyngioma in children
Authors: Hoffman Harold J. , Hendrick E. Bruce , Humphreys Robin P. , Buncic J. Raymond , Armstrong Dawna L. , Jenkin Richard D. T.
Published: May 2009

✓ The authors reviewed 48 cases of craniopharyngioma in children treated during 25 years, 1950 to 1975. Complete excision of the tumor, attempted in 23 patients, was possible in 17. The authors advocate aggressive treatment aimed at complete excision of the tumor, using radiotherapy only when adherence of the tumor to the internal carotid artery precludes total excision, and symptoms recur.
A prospective study of tracheobronchial bacterial flora in acutely brain-injured patients with and without antibiotic prophylaxis
Authors: Goodpasture Hewitt C. , Romig Donald A. , Voth Douglas W. , Liu Chien , Brackett Charles E.
Published: May 2009

✓ The authors observed prospectively 28 brain-injured patients, who required respiratory tract intubation, to determine the effect of antibiotic prophylaxis on bacterial flora, the rate of flora change, and the appearance of infection. Antibiotics not only failed to alter the rate of abnormal colonization but were associated with an earlier appearance of Gram-negative bacilli, the organisms that produced the most severe infections. Although more infections occurred in patients initially untreated with antibiotics, these infections were usually mild and caused by organisms susceptible to highly effective and relatively safe drugs. Although highly reproducible as a laboratory determination, the nitroblue tetrazolium dye test score showed no consistent relationship with the presence or absence of bacterial infection. Regular and extensive clinical and laboratory observations, including cultures of the respiratory tract, helped to make the antibiotic administration in these patients specific, appropriate, and reasonable. Broad spectrum antibiotic prophylaxis does not prevent and may enhance the development of severe pulmonary infection in these patients.
Experimental head injury in the rat
Authors: Nilsson Bengt , Pontén Urban , Voigt Gerhard
Published: May 2009

✓ Impact acceleration was used to elicit cerebral concussion in the albino rat. The pathophysiological response and morphological damage from the concussion were studied in groups of animals. The animals were grouped according to impact velocity (6–11 m/sec), and the threshold and different degrees of the concussive response were established. The concept of concussion as primarily a neuronal, functional disturbance was confirmed. However, this reaction was readily influenced by respiratory and circulatory changes, and morphological damage.

Defined reactions could be elicited in groups of animals according to impact velocity. Thus, the model appeared well standardized for further studies of concussion pathophysiology, expressed in terms of cerebral energy metabolism and blood flow.
Resection of a vertebral hemangioma after preoperative embolization
Authors: Hemmy David C. , McGee David M. , Armbrust Frederick H. , Larson Sanford J.
Published: May 2009

✓ Preoperative arterial embolization of a vertebral hemangioma allowed surgical excision of the vertebral body, restoration of normal anatomic continuity of the spinal canal, and improvement in myelopathy.
The syndrome of acute central cervical spinal cord injury after a gunshot lesion
Authors: Steudel Wolf I. , Ingunza William
Published: May 2009

✓ The authors describe a unique case in which a bullet was lodged in the spinal canal at the C2–3 level. The patient exhibited clinically the syndrome of acute central cervical spinal cord injury. The pathogenesis is discussed with reference to three similar cases in the literature.
An intracranial complication of nasogastric intubation
Authors: Wyler Allen R. , Reynolds Arden F.
Published: May 2009

✓ A case is presented in which a patient who had suffered severe facial fractures erroneously had a nasogastric tube placed in the intracranial cavity. It is believed that no such complication of nasogastric intubation has been reported previously.
Cisternoatrial, ventriculocisternal, and other cisternal shunts simplified
Authors: Spetzler Robert F. , Weinstein Philip R. , Chater Norman , Wilson Charles B.
Published: May 2009

✓ The authors describe a shunt inserted by a percutaneous route to the cisterna magna for the treatment of various cerebrospinal fluid disorders.
Evaluation of the age of subdural hematomas by computerized tomography
Authors: Scotti Giuseppe , Terbrugge Karel , Melançon Denis , Bélanger Gary
Published: May 2009

✓ The computerized tomography (CT) scans of 50 patients with surgically proven subdural hematomas were subdivided into three groups on the basis of the attenuation coefficients of the subdural fluid collections: 28% were more dense, 24% isodense, and 48% less dense than the surrounding brain. The 42 patients with the available data were then subdivided into three groups; acute, subacute, and chronic, according to the time interval between trauma or duration of symptoms and date of CT scanning. Subdural hematomas were found to be hyperdense in 100% of acute patients, isodense in 70% of the subacute group, and hypodense in 76% of the chronic group.
Glossopharyngeal neuralgia
Authors: Laha Ranjit K. , Jannetta Peter J.
Published: May 2009

✓ Various factors have been considered in the etiology and pathogenesis of glossopharyngeal neuralgia. Vascular compression of the involved cranial nerves has been demonstrated in sporadic cases. In this series of six patients, it was noted with the aid of the operating microscope that the ninth and tenth cranial nerves were compressed by a tortuous vertebral artery or posterior inferior cerebellar artery at the nerve root entry zone in five cases. In selected patients, microvascular decompression without section of the nerves may result in a cure.
Criteria for evaluating patients undergoing chemotherapy for malignant brain tumors
Authors: Levin Victor A. , Crafts David C. , Norman David M. , Hoffer Paul B. , Spire Jean-Paul , Wilson Charles B.
Published: May 2009

✓ The authors describe their criteria for evaluating brain-tumor patients, and present a numerical rating scale devised to designate response to testing. They discuss the reliability of test combinations that permit accurate prediction of response or deterioration during therapy in their experience with 100 patients treated on the Chemotherapy Service at the Brain Tumor Research Center, University of California, San Francisco School of Medicine. Specifically, the paper summarizes the predictive value of the neurological examination, radionuclide scintiscan, computerized tomographic brain scan (CT scan), and electroencephalogram (EEG), in the determination of response (tumor regression) or deterioration (tumor growth) during brain-tumor chemotherapy and chemotherapy-radiotherapy.

By retrospective analysis, the neurological examination, radionuclide scintiscan, and CT scan were of equal value individually as tests to predict response to therapy. However, the prognostic values of the neurological examination or the radionuclide scintiscan proved moderately superior to the CT scan in predicting deterioration during therapy. Under circumstances whereby a neurological examination, radionuclide scintiscan, and CT scan were all performed during the same testing session, and steroid dosage was carefully monitored, two of the three tests accurately predicted deterioration in 65% of patients, and response to therapy in 82% of patients. Two of the three tests correctly established deterioration in the remaining 35% of patients, and response in the remaining 18% of patients, when the two positively correlated tests had occurred within a mean period of 7 weeks.
Blood flow and oxygen consumption of the focally traumatized monkey brain
Authors: Martins Albert N. , Doyle Thomas F.
Published: May 2009

✓ The exposed left superior frontal gyrus of the anesthetized macaque brain was focally traumatized by a jet of compressed air. Focal blood flow in tissue around the lesion and total cerebral blood flow was determined before and during the 4 hours after trauma by the hydrogen clearance technique. Blood flow fell in tissue adjacent to the injured brain but the reduction was not statistically significant. Total cerebral blood flow, blood flow in the right superior-frontal gyrus, and oxygen consumption of the brain was unaffected by the trauma. The authors conclude that neither spreading ischemia within uninjured tissue surrounding focally traumatized brain nor post-traumatic diaschisis is readily provoked in the anesthetized brain of the monkey.
Electrophysiological studies of long-term electrical stimulation of the cerebellum in monkeys
Authors: Babb Thomas L. , Soper Henry V. , Lieb Jeffrey P. , Brown W. Jann , Ottino Carlos A. , Crandall Paul H.
Published: May 2009

✓ Six rhesus monkeys were stimulated on the paravermal cortex for 205 hours (18 days) with different charge densities in order to determine the electrode performance and neural damage that may result from long-term cerebellar stimulation comparable to that being used in man. The electrode-tissue interface was relatively stable and no neural damage was found when the charge/phase (0.5 µC/ph) or charge density (7.4 µC/sq cm/ph) was very low. At all higher charge levels tested (2.4, 4.8, 10, and 22 µC/ph), changes in the electrode-tissue interface, meningeal encapsulation, and neural damage were directly related to the charge density delivered. Unstimulated electrodes on the opposite paravermal cortex exhibited mild tissue reactivity and cell damage, probably due to mechanical compression of the molecular layer and pial vessels. Motor cortex field potentials could be evoked by charges as low as 0.1 µC/ph delivered to paravermal cortex; for a given charge/phase longer pulses were more effective than short pulses. After neural damage resulting from 205 hours of 4.8 µC pulses at 10 per second (total charge 14.76 C), the threshold for the motor cortex evoked potential increased by a factor of four or more. With the charge held constant to different-sized electrodes placed bilaterally in the same monkey, damage was greater under the smaller electrode. This finding suggests that the charge density to cerebellar cortex must be controlled to avoid neural damage.
Tissue reactions to long-term electrical stimulation of the cerebellum in monkeys
Authors: Brown W. Jann , Babb Thomas L. , Soper Henry V. , Lieb Jeffrey P. , Ottino Carlos A. , Crandall Paul H.
Published: May 2009

✓ Light and electron microscopic analyses were carried out on the stimulated and unstimulated paravermal cortices of six rhesus monkeys that had electrodes implanted on their cerebella for 2 months. The electrodes and the stimulation regime (10 p.p.s.: 8 min on, 8 min off) were similar to those used to stimulate the human cerebellum for treatment of certain neurological disorders. Mere presence of the electrode array in the posterior fossa for 2 months resulted in some meningeal thickening, attenuation of the molecular layer, and loss of Purkinje cells immediately beneath the electrode array. There was no evidence of scarring. After 205 hours of stimulation (7.38 × 106 pulses) over 18 days, a charge of 0.5 µC/ph or estimated charge density of 7.4 µC/sq cm/ph resulted in no damage to the cerebellum attributable to electrical stimulation per se. Such a charge/phase is about five times the threshold for evocation of cerebellar efferent activity, and might be considered “safe” for stimulation of human cerebellum. Charge density/phase and charge/phase were directly related to increased cerebellar injury in the six other cerebellar cortices stimulated. Leptomeningeal thickening increased with increased charge density. Injury included severe molecular layer attenuation, ongoing destruction of Purkinje cells, gliosis, ongoing degeneration of myelinated axons, collagen intrusion, and increased levels of local polysaccharides. In all cases, even with damage that destroyed all conducting elements beneath the electrodes, there was no damage further than 1 to 2 mm from the edges of the electrode arrays.
Elasticity of the spinal cord dura in the dog
Authors: Tunturi Archie R.
Published: May 2009

✓ The elasticity of the spinal cord dura in the dog has been investigated histologically, in situ, and by measurement. The dura was composed of collagenous and elastic connective tissue fibers. The collagenous fibers were arranged in longitudinal bundles, straight when stretched and wavy when unstretched, with a delicate network of fine elastic fibers coursing in all directions. Transecting the cord and dura at T-5 caused a separation of 25 to 30 mm of the dura and a 15- to 20-mm gap in the cord. By means of an appropriate sequence of transections of nerve roots and denticulate ligaments within the dura, and transections of the dural sheaths and nerves outside the dura, the strain on the dura was found to be imposed by the attachments of the dural nerve sheaths from T-6 to S-7. The filum terminale was not appreciably strained. By adding weights to a suspended dura, two components of elasticity were found. For loads of 0 to 50 gm, the incremental displacements in the length were large. The elastic modulus was about 4 × 106 dynes/sq cm, which was comparable to that of elastic fibers. For loads of 50 to 150 gm the displacements in length were small. The elastic modulus was about 5 × 108 dynes/sq cm, which was comparable to that of collagenous fibers.
The spinal cord central canal in kaolin-induced hydrocephalus
Authors: Torvik Ansgar , Murthy V. S.
Published: May 2009

✓ In order to study the cause of the great individual variations in kaolin-induced hydrocephalus, the lower brain stem and upper spinal cord were examined histologically in a series of young rabbits that had received injections of kaolin into the cisterna magna.

Animals with complete occlusion of the outlets from the fourth ventricle into the subarachnoid space showed only a moderate ventricular dilatation, while cases with marked hydrocephalus also had plugs of kaolin in the caudal part of the fourth ventricle. The intraventricular kaolin was adherent to the roof of the fourth ventricle by strands of connective tissue and it is suggested that the plugs served as valves that initially occluded the opening of the central canal and were then lifted away as the ventricle dilated and the roof moved posteriorly. The animals with marked hydrocephalus also had extensive dilatation of the central canal with cleft formation in the posterior columns. The observations support the concept that in hydrocephalus the central canal may serve as an alternative resorption route for the cerebrospinal fluid through communication with the spinal subarachnoid space.
Significance of vasospasm in the treatment of ruptured intracranial aneurysms
Authors: Saito Isamu , Ueda Yasuichi , Sano Keiji
Published: May 2009

✓ The authors have analyzed a total of 96 consecutive cases in which vasospasm followed subarachnoid hemorrhage (SAH). The SAH was caused by ruptured intracranial aneurysm or developed after aneurysm surgery. Usually at least 4 days elapsed between SAH and the onset of vasospasm. Vasospasm subsided an average of 2 weeks after onset. Of 68 patients with preoperative vasospasm, eight died due to cerebral edema resulting from ischemia, and 49% of the survivors had neurological deficits. Preoperative vasospasm was not aggravated by surgical intervention when operations were carried out more than 7 days after the onset of vasospasm. Postoperative vasospasm was found in 25 of 52 patients who underwent operation within 1 week after SAH (excluding cases in Grade V). Five of these patients died, all of whom underwent surgery between the fourth and seventh day after SAH (the day of SAH was counted as the first day). There were no deaths among 20 patients operated on within the first 3 days after SAH. Postoperative vasospasm was always mild in these cases, when it occurred, probably because blood clot or blood-stained cerebrospinal fluid was removed by operative procedures. In all cases, 4 to 11 days elapsed between the last SAH and the onset of postoperative vasospasm regardless of the timing of surgery.
Delayed breaking of a Heifetz aneurysm clip
Authors: Servo Antti , Puranen Matti
Published: May 2009

✓ An aneurysm of the left middle cerebral artery was treated by clipping with a Heifetz clip. The correct placement was confirmed angiographically immediately after the operation. At carotid angiography 1 year later the clip was found to have broken, and the aneurysm had increased in size.
Significance of intracranial hypertension in severe head injury
Authors: Miller J. Douglas , Becker Donald P. , Ward John D. , Sullivan Humbert G. , Adams William E. , Rosner Michael J.
Published: May 2009

✓ Measurements of intracranial pressure (ICP) were begun within hours of injury in 160 patients with severe brain trauma, and continued in the intensive care unit. Some degree of increased ICP (> 10 mm Hg) was present on admission in most cases (82%), and in all but two of the 62 patients with intracranial mass lesions requiring surgical decompression; ICP was over 20 mm Hg on admission in 44% of cases, and over 40 mm Hg in 10%. In patients with mass lesions only very high ICP (> 40 mm Hg) on admission was significantly associated with a poor neurological picture and outcome from injury, while in patients with diffuse brain injury any increase in ICP above 10 mm Hg was associated with a poorer neurological status and a worse outcome. Despite intensive measures aimed at prevention of intracranial hypertension, ICP rose over 20 mm Hg during the monitoring period in 64 of the 160 patients (40%). Postoperative increases in ICP over 20 mm Hg (mean) were seen in 52% of the patients who had had intracranial masses evacuated, and could not be controlled by therapy in half of these cases. Even in patients without mass lesions, ICP rose above 20 mm Hg in a third of the cases, despite artificial ventilation and steroid therapy. Of the 48 patients who died, severe intracranial hypertension was the primary cause of death in nearly half and even moderately increased ICP (> 20 mm Hg) was associated with higher morbidity in patients with mass lesions and those with diffuse brain injury. Measurement of ICP should be included in management of patients with severe head injury.
The role of HLA B27 in the diagnosis and management of low-back pain and sciatica
Authors: Bingham William F.
Published: May 2009

✓ Present diagnostic criteria for ankylosing spondylitis (AS) lean heavily on the x-ray examination, but there is much dispute as to its efficacy, especially in mild or early cases. Determinations of the HLA B27 histocompatibility antigen appear to define the population at risk far better than any other means. Of 31 patients who had the HLA B27 antigen, all had negative latex fixation tests and axial polyarthritic complaints (seronegative spondyloarthropathy or rheumatoid variant). Three had Reiter's syndrome and one had ulcerative colitis. Of the remaining 27 patients, nine had definite AS, 11 had probable AS, and seven had possible AS. Eleven of the 27 underwent at least one invasive spinal procedure (myelogram, laminectomy, fusion, facet denervation) before a diagnosis of AS was made.
The effect of norepinephrine on the spinal cord circulation and its possible implications in the pathogenesis of acute spinal trauma
Authors: Crawford Robert A. , Griffiths Ian R. , McCulloch James
Published: May 2009

✓ The effect of intra-arterially administered norepinephrine (NE) upon spinal cord blood flow (SCBF), before and after disruption of the blood-cord barrier was studied in dogs. Barrier disruption was accomplished with an intra-arterial bolus injection of 2.5 M urea. Multiple ligations of branches of the posterior aorta and cannula placements ensured that the urea was directed to the lumbar and sacral segments of the cord. The SCBF was measured by the hydrogen clearance method. Intra-arterial urea by itself had no significant effect on SCBF.

The intra-arterial infusion of NE (12 µg/min and 30 µg/min) was without overall effect on SCBF. However, if the blood-cord barrier had been previously disrupted with hypertonic urea, both concentrations of NE resulted in large reductions in SCBF. No such reductions in SCBF were seen with blood-cord barrier disruption and NE if the animals had been pre-treated with the α-blocker, phenoxybenzamine (1.5 mg/kg). Some aspects of the possible involvement of NE in the pathophysiology of acute spinal injury are discussed.
Subgaleal shunt for temporary ventricle decompression and subdural drainage
Authors: Perret George E. , Graf Carl J.
Published: May 2009

✓ The authors describe a closed method for temporary ventricle decompression and drainage of some chronic subdural hematomas and hygromas.
Pituitary apoplexy producing internal carotid artery occlusion
Authors: Rosenbaum Thomas J. , Houser O. Wayne , Laws Edward R.
Published: May 2009

✓ The authors report a case of pituitary apoplexy occurring several hours after carotid angiography. The event was associated with stupor, focal headache, and left hemiparesis. Repeat angiography demonstrated intracranial occlusion of the right internal carotid artery. At surgery, a hemorrhagic pituitary adenoma was found to be compressing the internal carotid artery, and the removal of the tumor resulted in restoration of flow. The mechanism, presenting symptoms and signs, and treatment of pituitary apoplexy causing compression of a major vessel are discussed.
Dysplastic gangliocytoma (Lhermitte-Duclos disease) of the cerebellum
Authors: Leech Richard W. , Christoferson Lee A. , Gilbertson Roger L.
Published: May 2009

✓ A case of dysplastic gangliocytoma, or Lhermitte-Duclos disease, of the cerebellum is reported. The patient was the seventh reported survivor of this rare disease. A review of the known biology of the disease allows some optimism. The treatment of choice appears to be surgical resection only.
Operative approach to persistent trigeminal artery producing facial pain and diplopia
Authors: Merry Glen S. , Jamieson Kenneth G.
Published: May 2009

✓ A case is reported of persistent trigeminal artery producing intermittent facial pain, the last episode being associated with diplopia. The trigeminal and abducent nerves were attached to the trigeminal artery by a congenital membrane. Blood supply to the vertebrobasilar system was via the persistent vessel. A new operative approach along the petrous-temporal ridge is described.
Spinal cord vascular malformations with symptoms during menstruation
Authors: Martin Raymond A. , Howard Frank M. , Salamone Charles R. , Reese David F.
Published: May 2009

✓ Two patients had the initial complaint of fluctuating paraparesis, which was most evident at menstruation. One patient had a semimonthly fluctuating deficit. Spinal cord compression and ischemia, secondary to the vascular mass, were considered the most likely mechanisms. Blood levels of estrogen and progesterone during the menstrual cycle may have had a contributory effect. Fluctuating spinal cord deficits associated with a consistent portion of the menstrual cycle should alert the physician to the possibility of an arteriovenous malformation of the spinal cord.
Sarcoidosis of the pineal gland
Authors: Schaefer Michael , Lapras Claude , Thomalske Guenther , Grau Holger , Schober Ralf
Published: May 2009

✓ The authors report a case of sarcoidosis of the pineal gland with no other organ manifestation of the disease. The tumor was successfully removed by a direct surgical approach.
Neurosurgery 1977: problems and attainments
Authors: Mount Lester A.
Published: May 2009

✓ The President of the American Association of Neurological Surgeons (AANS) discusses the many elements that appear to restrict the professional activities of neurosurgeons and other physicians. He stresses the importance of the active role required of the AANS, the American Medical Association, and the American College of Surgeons in finding solutions to problems related to neurosurgery.
Pain relief in metastatic cancer other than breast and prostate gland following transsphenoidal hypophysectomy
Authors: Tindall George T. , Nixon Daniel W. , Christy James H. , Neill Jimmy D.
Published: May 2009

✓ Hypophysectomy was performed in six patients with advanced carcinoma other than from breast and prostate gland to alleviate pain. Two patients received significant and lasting relief of pain; one achieved relief but died from progression of disease 5 weeks after surgery; one patient, initially relieved, had recurrence of pain 3 months later; one had about 50% relief; and one received no benefit. Possible mechanisms for pain relief include changes in pituitary hormones, prostaglandins, and the newly isolated brain peptides, alpha and beta endorphin. These preliminary observations will require further critical evaluation in a larger series to determine the effectiveness of hypophysectomy in relieving pain in cancer other than from the breast and prostate. The results, nevertheless, do imply that a different approach to pain, namely endocrine manipulation, may be beneficial in certain cancer patients.
The pressure-volume function of brain elasticity
Authors: Sklar Frederick H. , Elashvili Ilya
Published: May 2009

✓ The intracranial pressure-volume function as determined by brain elasticity is reported in normal dogs. Rapid subarachnoid infusions clearly define an exponential relationship between pressure and volume. An aliquot technique to measure elastance (dP/dV) at multiple intracranial pressures demonstrates a linear relationship between elastance and pressure. This follows mathematically from the exponential nature of the basic pressure-volume function.

The clinical significance of brain elastance measurements is discussed. It is emphasized that the effects of pressure on CSF dynamics are superimposed on the pressure-volume function of brain elasticity and probably account for the process of spatial compensation for an expanding mass lesion. It is not apparent that elastance measurements can serve as indicators of impending decompensation, since the pressure-volume function of brain elasticity provides no direct information about CSF dynamics. Accordingly, the clinical usefulness of elastance measurements is seriously questioned.
Compartmental analysis of regional cerebral blood flow in patients with acute severe head injuries
Authors: Enevoldsen Erna M. , Jensen Finn Taagehøj
Published: May 2009

✓ Bicompartmental analysis for the calculation of regional cerebral blood flow (rCBF) from 133Xe clearance in brain tissue has not been thoroughly explored in clinical studies. Most authors rely either on the average rCBF obtained by height/area analysis of the clearance curves or on the initial-slope flow index. Possibly the reason is that the validity of the bimodal flow distribution in abnormal brain tissue is considered questionable. In the present study, bicompartmental analysis, performed by a least-square computerized iterative approach, was used in the calculation of the flow and weight of the tissue of the brain of patients with severe head injuries. The analysis was found to give important information of the nature and course of the brain lesions even if the clearance curves did not have the normal bi-exponential shape, provided the results obtained were properly interpreted. In such cases, the values of the flow and relative weight could not be taken as flow and weight values of gray and white matter, but rather as indices of fast and slower flow components. The interpretation of the results was based on the identification of three types of 13-minute clearance curves, each being characteristic of a type of brain lesion. The clearance curves from fairly normal brain tissue appeared to be bi-exponential; curves from areas of severe cortical contusion had, in addition, an initial and rapid “third” component, a tissue peak, whereas curves from severely edematous brain tissue approached the monoexponential shape.
Microsurgical exposure of the petrous portion of the carotid artery
Authors: Paullus Wayne S. , Pait T. Glenn , Rhoton Albert L.
Published: May 2009

✓ Occlusion of the cervical portion of the internal carotid artery (ICA) has been treated by vein graft bypass from the common carotid to the supraclinoid segment. However, this procedure has the disadvantages of requiring temporary occlusion of collateral flow, the short length of ICA available for anastomosis, and the retraction required for exposure of the supraclinoid area. In an attempt to find a more suitable bypass site for grafting, the petrous portion of 50 carotid arteries was studied in cadavers. It was found that there was a 1-cm length of the horizontal segment of the petrous carotid that could be exposed in the floor of the middle fossa lateral to the trigeminal nerve. This segment was covered by dura only or a thin layer of cartilage in approximately half of the specimens. In the remainder, there was often a thin shell of bone covering the artery, which could be drilled away. The petrous portion of the carotid artery had branches in only 38% of specimens, a Vidian branch in 30%, and a periosteal branch in 8%. The carotico-tympanic artery, previously reported to be the most common branch, was not found in a single case. These branches allow the retrograde flow needed to maintain the patency of this segment following proximal occlusions. The relationship of the carotid artery to structures that might be injured in exposing the petrous portion of the artery was reviewed; these structures include the cochlea, middle ear, Eustachian tube, tensor tympani muscle, geniculate ganglion, and facial, greater petrosal, and trigeminal nerves.
Nerve allografts and histocompatibility in dogs
Authors: Singh Ram , Vriesendorp Huibert M. , Mechelse Karel , Stefanko Stanislaw
Published: May 2009

✓ The histocompatibility requirements for successful frozen nerve allografts were studied in 46 dogs. Major canine histocompatibility (DLA) differences appeared to be of vital importance for nerve regeneration and function, as judged by histological and electromyographic performance 7 to 9 months after grafting. Minor histocompatibility differences did not appear to lead to rejection of the frozen nerve allografts. Graft irradiation did not improve the acceptability of frozen DLA-mismatched grafts. The effect of DLA matching was much more pronounced in allografts 7 cm long than in allografts 4 cm long. The results indicate the need for a bank of frozen human histocompatible (HLA) nerve allografts, and a study of the effect of partial or complete HLA matching on their survival.
Fatal meningitis secondary to undetected bacterial psoas abscess
Authors: Orrison William W. , Labadie Enrique L. , Ramgopal Vadakepat
Published: May 2009

✓ Three unusual cases of fatal meningitis secondary to undetected bacterial psoas abscess occurred at this institution over an 11-year period. All three patients had suffered chronic debilitating disorders before the abscess formation. The superimposed variable clinical presentations led to the initial diagnosis of a progressing cerebrovascular accident in one case, herniated nucleus pulposus at the L3–4 level in another, and osteomyelitis of the hip joint in the third. Analysis of these cases revealed that before the meningeal dissemination, all of the patients had shown evidence of intra-abdominal pathology with positive psoas signs. Diagnostic and therapeutic guidelines are discussed.
The management of ruptured intracranial aneurysm in sickle cell anemia
Authors: Close Richard A. , Buchheit William A.
Published: May 2009

✓ The problem of sickle cell disease and its complications is discussed. Subarachnoid hemorrhage is not a common complication of sickle cell disease and should be evaluated in the same way as if it were not associated with the disease. Patients with sickle cell trait have an added risk during angiography and hypotensive anesthesia. Guidelines are given for angiography and craniotomy with hypotensive anesthesia and reduction of brain volume in these patients.
Spontaneous transdural extension of malignant astrocytoma
Authors: Kawano Nobuyuki , Yada Kenzoh , Ogawa Yoshihiro , Sasaki Kenichi
Published: May 2009

✓ A case of malignant astrocytoma in the frontoparietal parasagittal region with transgression into the overlying dura mater and the skull is presented. Spontaneous transdural extension of a glioma is an extremely rare growth pattern. A mode of transdural extension of this tumor is discussed and related reports are reviewed.