bluuebunny/crossref_metadata_2025_split huggingface dataset:
Platelet interaction within giant intracranial aneurysms
Authors: Sutherland Garnette R. , King Martin E. , Peerless S. J. , Vezina William C. , Brown G. William , Chamberlain Mike J. 
Published: May 2009

✓ Turbulence within intracranial aneurysms may result in tearing of the aneurysmal wall, exposing the subendothelial matrix to circulating platelets. In this study, platelet interaction in giant intracranial aneurysms was evaluated by a dual-isotope technique employing 111In-labeled platelets and 99mTc-labeled red blood cells. The use of two isotopes allows the subtraction of the blood pool and the calculation of the ratio indium deposited:indium blood pool (In(D)/In(BP)). A ratio greater than zero indicates platelet deposition within the aneurysm.
Thirteen patients were evaluated in this way, with platelet deposition demonstrated in six. In these six patients, the ratio In(D)/In(BP) was found to be significantly elevated, with a mean value of 0.96 ± 0.65. Three of these six patients had symptoms of recurrent transient neurological deficits; one of these three suffered a complete stroke following documentation of platelet deposition. In this case, the aneurysm was obtained at surgery and was found to contain intraluminal platelet aggregation when viewed by scanning electron microscopy. In the remaining seven patients, the ratio In(D)/In(BP) was found not to be significantly elevated (mean −0.03 ± 0.06), indicating the absence of active platelet deposition. Two of these patients had prior symptoms of cerebral ischemia; one of these was found to have an ulcer in the ipsilateral internal carotid artery which was probably responsible for thromboembolic events to the hemisphere.
The authors conclude that platelet aggregation occurs more frequently than previously recognized in giant intracranial aneurysms, and their data substantiate the hypothesis that platelet metabolic products or thrombi originating from a large aneurysm may embolize to distal cerebral vessels.
Statistical analysis of central nervous system tumors in China
Authors: Huang Wen-qing , Zheng Shi-ju , Tian Qing-sheng , Huang Jian-qing , Li Yu-xia , Xu Qing-zhong , Liu Zi-jun , Zhang Wen-cui 
Published: May 2009

✓ The authors present a statistical survey of the general incidence, age distribution, and preferential sites of 25,122 tumors of the central nervous system (CNS), from 12 centers in China. Of these tumors, 22,457 were intracranial and the rest intraspinal.
Of the 22,457 intracranial neoplasms collected, tumors of neuroepithelial tissue comprised 43.85%, meningiomas 16.58%, tumors of nerve sheath cells 9.5%, pituitary adenoma 9.52%, congenital tumors 8.46%, secondary tumors 6.8%, vascular malformations and tumors 3.82%, and primary sarcomas 0.72%. Neuroepithelial and meningeal tumors occurred first and second in all series, but the other tumors varied in frequency. There was a higher incidence of nerve-sheath tumors in southern than in northern regions. The age distribution of Chinese patients with tumors of the CNS was lower than that of Caucasians: nearly two-thirds (64.57%) had the clinical onset of their tumor between the ages of 31 and 40 years, with the peak incidence at 35 years. Nearly 20% of tumors of the CNS occurred before 20 years of age. The male:female ratio was 1.53:1; the only tumor with a definite preponderance of females over males was the meningioma.
Intraspinal tumors derived from nerve sheaths comprised 47.13% of all tumors within the spinal canal. Meningiomas were second with an incidence of 14.06%, then followed congenital tumors (12.06%) and neoplasms of neuroepithelial tissue (10.83%). Secondary tumors, vascular malformations and neoplasms, and sarcoma were next in order of frequency with 4.6%, 4.5%, and 4.16%, respectively.
Management of intrauterine hydrocephalus
Authors: Cochrane David D. , Myles S. Terence 
Published: May 2009

✓ The aggressive treatment of hydrocephalus has been of benefit to many children. Sophisticated two-dimensional ultrasound techniques allow the diagnosis of prenatal hydrocephalus to be made with accuracy and ease. In the past, the medical decisions governing the management of hydrocephalus in utero were made by obstetricians and were directed at reducing maternal mortality and morbidity. Now, with improved diagnosis and support facilities for the newborn, neurosurgical input is being requested as more concern is expressed for the fetus.
Based on their experience with seven cases of intrauterine hydrocephalus in the past 3 years, the authors present their program for the management of this problem. If antenatal ultrasonography shows hydrocephalus without other anomalies, they recommend that the fetus be born by elective Caesarean section at the time of pulmonary maturity, and that early ventricular shunting be carried out. This plan should minimize nervous system trauma resulting from hydrocephalus and the birth process. If, however, antenatal diagnostic studies show cerebral or other major system anomalies in addition to hydrocephalus, then standard obstetrical care should be given. Antenatal ultrasonography has been found to be reliable in assessing fetal lateral ventricular size and shape, and to correlate well with the results of postnatal computerized tomography scanning.
Hemifacial spasm
Authors: Iwakuma Tsutomu , Matsumoto Akihisa , Nakamura Nishio 
Published: May 2009

✓ Patients with hemifacial spasm were treated by three different surgical procedures: 1) partial sectioning of the facial nerve just distal to the stylomastoid foramen; 2) selective neurectomy of facial nerve branches; and 3) microvascular decompression. A retromastoid craniectomy with microvascular decompression was most effective in relieving hemifacial spasm and synkinesis.
In a postmorten examination on one patient, microscopic examination of the facial nerve, which was compressed by an arterial loop of the posterior inferior cerebellar artery at the cerebellopontine angle, revealed fascicular demyelination in the nerve root. On the basis of surgical treatment, electromyography, and neuropathological findings, the authors conclude that compression of the facial nerve root exit zone by vascular structures is the main cause of hemifacial spasm and synkinesis.
A 10-year experience in the treatment of trigeminal neuralgia
Authors: van Loveren Harry , Tew John M. , Keller Jeffrey T. , Nurre Mary A. 
Published: May 2009

✓ Of 1000 patients with classic trigeminal neuralgia who were treated during the last 10 years, 90% had an initial favorable response to medical therapy, but 75% (750 patients) failed to achieve satisfactory long-term relief. Of these, 700 patients were treated by percutaneous stereotaxic rhizotomy (PSR) and 50 were selected for posterior fossa exploration (PFE).
Of the 50 patients undergoing PFE, 82% had neurovascular contact at the trigeminal root entry zone, but only 46% were judged to have had significant neurovascular compression. Exploration was negative in 16% of patients and revealed neural compression by bone in 2%. Patients with neurovascular compression were treated by microvascular decompression (MVD); all other patients with exploratory surgery underwent partial sensory rhizotomy. At 3 years after PFE, 84% of patients are pain-free. Results are excellent in 68%, good in 12%, fair in 4%; 12% had a recurrence of their neuralgia. The 700 patients treated by PSR have been followed for 6 years. Results are excellent in 61%, good in 13%, fair in 5%, and poor in 1%; 20% had a recurrence.
This study indicates that there is no significant difference in results between PSR and PFE in the treatment of trigeminal neuralgia. The concept that neurovascular compression is a mechanical factor in the etiology of trigeminal neuralgia was supported, but neurovascular compression was less common than previously reported. Percutaneous stereotaxic rhizotomy is a less formidable procedure than PFE, and is easily repeated. Recent technical advances have improved the results obtained with PSR. Therefore, PSR remains the procedure of choice for the majority of patients with trigeminal neuralgia.
Computerized tomographic and pathologic studies of the untreated, quiescent, and recurrent glioblastoma multiforme
Authors: Burger Peter C. , Dubois Philip J. , Schold S. Clifford , Smith Kenneth R. , Odom Guy L. , Crafts David C. , Giangaspero Felice 
Published: May 2009

✓ Pathological findings in 20 cases of glioblastoma multiforme were correlated with clinical histories and computerized tomographic (CT) scans. This was done to define the neoplasm in three stages: before treatment, during remission, and during recurrence.
The untreated lesions were markedly cellular neoplasms composed predominantly of small anaplastic cells. The radiographic central region of low density was necrosis, the enhancing rim was a cellular zone of viable neoplasm, and the perilesional low-density area was edema with infiltrating tumor. In these 20 cases, all of the identifiable neoplasms lay within the zone of peritumoral edema or contrast enhancement, although small anaplastic cells may have been present in more distant regions. The lesions in remission were remarkable for their minimal mass effect, discrete nature, extensive necrosis, and content of large bizarre glia. The large cells were confined to the original tumor bed and were consistent with neoplastic cells inactivated and immobilized by radio- and chemotherapy. These lesions were accurately localized by CT scanning. The recurrent lesions were heterogeneous, but most were formed of widely disseminated small anaplastic cells. The highly cellular regions of such lesions could be localized by CT scanning, but CT could not detect less cellular foci in the cerebrum, cerebellum, or brain stem. In one patient, the contrast-enhancing lesions of “recurrence,” were foci of radionecrosis, underscoring the difficulty in distinguishing this entity from recurrent neoplasm.
Improved treatment of a brain-tumor model
Authors: Rosenblum Mark L. , Gerosa Massimo A. , Dougherty Dolores V. , Wilson Charles B. 
Published: May 2009

✓ Clonogenic cell and animal survival studies were used to determine the most effective BCNU therapy schedule in the 9L rat brain-tumor model. Survival of tumor cells following a single LD10 dose of BCNU (13.3 mg/kg intraperitoneally) was compared to cell survival after one to four daily 0.5 × LD10 doses. The posttreatment kinetics of surviving clonogenic cells were investigated at various times after BCNU was given in single doses of 0.25 to 1 × LD10 and in two daily doses of 0.5 × LD10. The cell kill was greater, time to reinitiation of cell growth was later, posttreatment rate of clonogenic cell proliferation was slower, and the interval to total repopulation of the clonogenic cell pool was longer with a single LD10 dose as compared to the multiple-dose schedules. Animal survival studies confirmed that a single LD10 dose of BCNU was at least as effective as a cumulative level of up to 1½ times that amount when treatment was administered in smaller doses, regardless of the fractionation schedule.
Clinical experience with patients harboring malignant brain tumors has shown that a single BCNU dose of 185 to 200 mg/sq m is tolerated well. Results of these animal experiments suggest that this therapy should have anti-tumor activity at least equivalent to the more commonly employed schedule of 80 mg/sq m/day given for 3 days. Although direct comparison of treatment efficacy using the two schedules is not possible, no adverse clinical effects have been observed with the recently adopted single-dose schedule. Furthermore, the duration of patient hospitalization for chemotherapy has decreased.
Late seizures and morbidity after subdural empyema
Authors: Cowie Richard , Williams Bernard 
Published: May 2009

✓ A survey of 89 patients with subdural empyema was conducted to assess the incidence of late seizures and morbidity in this disease. Twenty-four patients died during the acute stage of the illness and, of the 65 survivors, 13 were lost or had incomplete follow-up review. Hemiparesis occurred in 48 of the survivors during the acute stage, and all but nine recovered completely. Thirteen patients had a visual field deficit and all recovered; in three of these 13 who had speech disorders the deficits persisted. Recovery from neurological morbidity was not related to the type of surgical treatment; however, the mortality rate was improved by craniotomy.
The same incidence of early seizures occurred in those who died (62%) as in those who survived (63%). Of those who had no early seizures, 42% had late seizures, the majority appearing within 16 months. Of those who had early seizures, 71% did not have subsequent attacks. The highest incidence of seizures occurred in patients who had their empyema in the second and third decades of life. The incidence of late seizures was not influenced by the method of surgical treatment, the degree of deterioration of consciousness during the acute stage of the illness, nor by occurrence of early seizures. A significantly increased incidence of early seizures was associated with paranasal sepsis, but not with late seizures.
Monitoring of antifibrinolytic therapy following subarachnoid hemorrhage
Authors: Sawaya Raymond , Sonnino Victor , McLaurin Robert L. , Perrotta Gerardo 
Published: May 2009

✓ Ten cases of subarachnoid hemorrhage (SAH) from ruptured cerebral aneurysm are reported. Fibrin/fibrinogen degradation product (FDP) levels were determined simultaneously in blood and cerebrospinal fluid (CSF) at an average frequency of 1.7 days, extended over periods of 8 to 63 days. Successful antifibrinolytic therapy (AFT) correlated with FDP levels in CSF of less than 16 µg/ml. Five patients failed to respond to AFT. Levels of FDP in the CSF fluctuated widely in these five patients, and remained at or above 16 µg/ml for most of the monitoring period. Blood FDP levels were normal or minimally elevated, and could not be used in predicting or preventing rebleeding episodes. A hypothesis is presented to explain the significance of the presence of FDP's in CSF.
In spite of the many techniques employed in monitoring AFT and reviewed in this paper, little information has been gained to improve the results and therapeutic strategies. Among the different methods available, FDP measurements in the CSF have correlated best with rebleeding, and thus may be used in modifying and individualizing therapy. Suggestions are given for future studies.
Cerebral arterial pathology in experimental subarachnoid hemorrhage
Authors: Yamashima Tetsumori , Yamamoto Shinjiro 
Published: May 2009

✓ Pathological changes of the cerebral arteries were studied in 30 dogs after subarachnoid injections of saline, fresh autologous blood, epinephrine, blood plus epinephrine, norepinephrine, or blood plus norepinephrine. Macroscopically, the circle of Willis was maximally dilated after the injection of epinephrine and was constricted following administration of blood plus epinephrine. Microscopically, neither saline nor blood produced abnormalities, except for minor changes of the adventitia in the latter. Epinephrine produced frank necrosis of smooth-muscle cells, which was subsequently replaced by fibrosis in the media of larger subarachnoid arteries, and the leakage of necrotic material from the infarcted hypothalamus contributed to these lesions. Blood plus epinephrine produced marked changes in the internal elastic lamina and tortuosities of the nuclei of smooth-muscle cells, while norepinephrine and blood plus norepinephrine produced only minor changes.
Previously reported findings of morphological changes due to vasospasm after subarachnoid hemorrhage were confirmed experimentally, but such changes were found only after application of epinephrine. It is suggested that epinephrine produced the most severe vasospasm among the five substances tested.
Electrophrenic respiration following anastomosis of phrenic with brachial nerve in the cat
Authors: Krieger Abbott J. , Danetz Irina , Wu Shu Z. , Spatola Mark , Sapru Hreday N. 
Published: May 2009

✓ Patients with high spinal cord injuries may be totally dependent on artificial ventilation. Prolonged use of mechanical devices requires intensive care, which restricts the mobility of these patients. Electrophrenic respiration has been used with success to overcome this difficulty. However, a prerequisite for electrophrenic respiration is a viable phrenic nerve. Patients with spinal cord injuries at the C-3 to C-5 levels do not have a viable phrenic nerve due to gradual degeneration of axons in these nerves.
In the present study on cats, the authors caused degeneration in one of the phrenic nerves by sectioning it low in the neck. Then the distal end of the phrenic nerve was anastomosed to the proximal segment of a sectioned brachial nerve. Sixteen to 32 weeks were allowed for the growth of brachial axons into the anastomosed phrenic nerve. Each cat served as its own control because one of the phrenic nerves was left intact. It was observed that pacing of the anastomosed phrenic nerve produced respiration comparable to spontaneous respiration or to respiration induced by pacing the intact phrenic nerve. Lack of rhythmic bursts of electrical activity in the anastomosed phrenic nerve and electromyographic activity in the ipsilateral hemidiaphragm confirmed that the anastomosed phrenic nerve remained disconnected from the respiratory motoneurons. Abundance of collagen matrix in the electron micrographs of the anastomosed phrenic nerve indicated that degeneration of the axons of phrenic motoneurons had occurred and the brachial nerve had grown into the phrenic nerve stump. These results indicate that electrophrenic respiration may be possible in patients with spinal cord injuries at the C-3 to C-5 vertebral levels if the phrenic nerve is kept viable by anastomosing it to a branch of the brachial nerve.
Gram-negative bacillary meningitis in neurosurgical patients
Authors: Mombelli Giorgio , Klastersky Jean , Coppens Lyne , Daneau Didier , Nubourgh Yves 
Published: May 2009

✓ The authors report 34 cases of Gram-negative bacillary meningitis related to traumatic cranial lesions or neurosurgery observed between 1973 and 1980 at two neurosurgical units (Institut J. Bordet, Brussels, and Inselspital, Bern). As a typical nosocomial infection, meningitis developed after prolonged hospitalization in most patients, and was mainly due to highly resistant organisms, such as P. aeruginosa and Klebsiella sp. At least 65% of the patients were colonized with the pathogen responsible for the meningitis before the onset of the infection. Ventriculitis, including four cases of ventricular empyema, complicated meningitis in all the 17 patients in whom a ventricular tap was performed. The results of treatment were unsatisfactory. Fifty percent of the patients were cured of their infection, but only 30% survived; 15% of the patients died within 48 hours following diagnosis.
The optimum treatment of postsurgical Gram-negative meningitis remains in doubt. The choice of initial antibiotics should take into account the sensitivity patterns of colonizing microorganisms. Chloramphenicol is ineffective against most pathogens commonly involved in this infection. Intrathecal aminoglycosides may fail in the presence of ventriculitis. Intraventricular aminoglycosides are probably justified in critically ill patients. The role of the newer cephalosporins and of co-trimoxazole remains to be defined.
Beneficial effects of induced hypertension on experimental stroke in awake monkeys
Authors: Hayashi Seiji , Nehls Daniel G. , Kieck Charles F. , Vielma Juan , DeGirolami Umberto , Crowell Robert M. 
Published: May 2009

✓ The authors performed a controlled study of induced hypertension therapy for treatment of experimental stroke in unanesthetized monkeys. Ten control and 10 treated animals were subjected to a 4-hour occlusion of the middle cerebral artery (MCA) by an implanted tourniquet. Neurological status and local cerebral blood flow (CBF) were monitored serially. Local CBF was determined by hydrogen clearance in and around the elevated 20% to 40% by intravenous infusion of phenylephrine hydrochloride. Neuropathological evaluation was performed after about 2 weeks.
A 4-hour occlusion of the MCA in control animals caused moderate stable neurological deficits, moderate stable decreases in local CBF, and medium-sized infarcts. With induced hypertension, five of 10 treated animals showed neurological improvement, and eight exhibited increased CBF in the ischemic zone. Average infarct size tended to be smaller in the treated group, although the difference did not reach statistical significance. Hemorrhagic infarcts were not observed. In four animals, phenylephrine caused cardiac dysrhythmias and hypotension which were reversed by appropriate measures. In this unanesthetized primate model of moderate experimental stroke, induced hypertension had beneficial effects on neurological status, local CBF, and infarct size without causing hemorrhagic infarction. Induced hypertension may be beneficial for some clinical cases of focal cerebral ischemia.
Microvascular patch technique with and without Silastic T-tube bypass
Authors: Haines Peter C. , Donaghy R. M. Peardon 
Published: May 2009

✓ Poor patency results in the surgery of small vessels operated on between 1959 to 1964 was demonstrated to be in part due to the long period of occlusion of the operated vessel during surgery and the presence of a foreign body (suture) in the lumen of the vessel postoperatively. New suture techniques and T-tube bypass were introduced at that time. New experimental data have not been extensively sought since that time. To provide further current data regarding the above observations, 110 arterial vessels (60 carotid arteries 1.1 to 1.3 mm in outside diameter (OD) and 50 femoral arteries 0.6 to 0.7 mm OD) were operated on in rats to compare the bypass versus non-bypass and vein patch closure techniques. In 1-mm vessels, patency rates 1 month after surgery were 100% regardless of the use of bypass or type of closure. Improved visualization, better suture material, and improved surgical skill were probably chiefly responsible for this success. The success rate was not as encouraging, however, in vessels of 0.6 mm OD.
The following points are brought out: 1) The presence of the bypass causes damage to the intima in 0.6 mm OD vessels and should not be used. Smaller bypasses do not conduct blood well. 2) Bypass is not required in 1-mm vessels as the patency rate is satisfactory and not altered by its use. 3) The major indication for T-tube bypass is in vessels of 1 mm OD and larger, that nourish tissue which would be damaged by vascular occlusion for 20 to 40 minutes. 4) Foreign body (suture) in the lumen is poorly tolerated in 0.6 mm vessels, but can be tolerated more easily in larger vessels. 5) Techniques that limit the amount of suture material in the lumen are indicated in 0.6-mm vessels. 6) After 1 month, suture material has an epithelial covering and if patency has been maintained for that period of time it is likely to remain.