bluuebunny/crossref_metadata_2025_split huggingface dataset:
Brain edema formation and neurological impairment after subarachnoid hemorrhage in rats
Authors: Thal Serge C. , Sporer Sonja , Klopotowski Mariusz , Thal Simone E. , Woitzik Johannes , Schmid-Elsaesser Robert , Plesnila Nikolaus , Zausinger Stefan 
Published: May 2009

Object
Global cerebral edema is an independent risk factor for early death and poor outcome after subarachnoid hemorrhage (SAH). In the present study, the time course of brain edema formation, neurological deficits, and neuronal cell loss were investigated in the rat filament SAH model.

Methods
Brain water content and neurological deficits were determined in rats randomized to sham (1-, 24-, or 48-hour survival), SAH by endovascular perforation (1-, 24-, or 48-hour survival), or no surgery (control). The neuronal cell count (CA1–3) was quantified in a separate set of SAH (6-, 24-, 48-, or 72-hour survival) and shamoperated animals.

Results
Brain water content increased significantly 24 (80.2 ± 0.4% [SAH] vs 79.2 ± 0.1% [sham]) and 48 hours (79.8 ± 0.2% [SAH] vs 79.3 ± 0.1% [sham]) after SAH. The neuroscore was significantly worse after SAH (33 ± 15 [24 hours after SAH] vs 0 ± 0 points [sham]) and correlated with the extent of brain edema formation (r = 0.96, p < 0.001). No hippocampal damage was present up to 72 hours after SAH.

Conclusions
Brain water content and neurological dysfunction reached a maximum at 24 hours after SAH. This time point, therefore, seems to be optimal to test the effects of therapeutic interventions on brain edema formation. Neuronal cell loss was not present in CA1–3 up to 72 hours of SAH. Therefore, morphological damage needs to be evaluated at later time points.
Endoscopic third ventriculostomy for obstructive hydrocephalus due to intracranial hemorrhage with intraventricular extension
Authors: Oertel Joachim M. K. , Mondorf Yvonne , Baldauf Joerg , Schroeder Henry W. S. , Gaab Michael R. 
Published: May 2009

Object
Endoscopic third ventriculostomy (ETV) is well accepted for obstructive hydrocephalus of various etiologies. Nevertheless, it is seldom considered in intracranial hemorrhage even in cases involving obstruction of the CSF circulation.

Methods
Between May 1993 and April 2008, 34 endoscopic procedures were performed for hemorrhage-related obstructive hydrocephalus with an intraventricular component. All patients were prospectively followed up. Special attention was paid to presurgical clinical status, type of hemorrhage, type of surgery, postsurgical clinical status, postsurgical ventricular size, and necessity of ventriculoperitoneal shunt implantation.

Results
An ETV was performed for treatment of obstructive hydrocephalus due to intracranial hemorrhage in 34 patients (15 male, 19 female; mean age 60.8 years [range 3 months–83 years]). Hydrocephalus was caused by 17 cerebellar, 6 thalamic, 5 intraventricular, 3 basal ganglia, 2 subarachnoid, and 1 pontine hemorrhage. Thirty-three patients (97.1%) presented with impaired consciousness. Intraventricular blood was present in all cases. In 16 cases (47.1%), blood clots had to be evacuated to achieve access to the third ventricle floor. The mean operation time was 58.2 minutes (range 25–120 minutes). Three complications occurred (rate of 8.8%) with 2 being asymptomatic (5.9%) and 1 being transient (2.9%). There was no procedure-related permanent morbidity, and no procedure-related mortality. After surgery, there was clinical improvement in 17 cases (50.0%) and radiological evidence of improvement in 22 cases (64.7%). Two patients required postoperative ventriculoperitoneal shunting (5.9%). Seven patients died of hemorrhage while in the hospital (20.6%), and another 4 died during follow-up (11.8%). Fifteen patients (44.1%) showed a persistent clinical improvement at the final follow-up (mean 12.2 months after surgery).

Conclusions
Endoscopic third ventriculostomy represents a safe treatment option in intraventricular hemorrhage–related obstructive hydrocephalus yielding similar results as an external drainage but with less risk of infection and a very low subsequent shunt placement rate. In cases with a predominant obstructive component, ETV should be considered in hydrocephalus due to intracerebral hemorrhage. However, performing an ETV with a blurred field of vision and distorted ventricular anatomy is a challenge for any endoscopic neurosurgeon and should be reserved for experienced neuroendoscopists.
Transkull focal lesions in cat brain produced by ultrasound
Authors: Fry Francis J. , Goss Stephen A. , Patrick James T. 
Published: May 2009

✓ Focused ultrasound has been used for focal modifications of brain tissue and in preliminary studies of the application of ultrasonic techniques for tissue modification in human stereotaxic neurosurgery; however, the technique has been seriously compromised by the necessity of removal of intervening skull. Such removal was necessary to avoid distortion and extremely large attenuation of the ultrasonic beam which resulted from passage through bone. Recent studies have shown that under proper conditions focal beams of ultrasound can be transmitted with tolerable distortion and attenuation through skull, suggesting the possibility of transkull lesion production in brain.
This report describes the acoustical parameters and histological features of focal brain lesions produced in 10 craniectomized cats with intense focal ultrasonic beams which first had passed through a formalin-fixed human skull overlay. The histological appearance of these lesions produced to date is similar to that produced previously without intervening skull.
Noninvasive localization of brain-stem lesions in the cat with multimodality evoked potentials
Authors: Greenberg Richard P. , Stablein Donald M. , Becker Donald P. 
Published: May 2009

✓ Multimodality evoked potential (MEP) data from over 300 comatose head-injured patients suggest that central nervous system dysfunction of the brain stem and/or hemispheres can be localized with this noninvasive neuroelectric technique. Based on this work, decerebrate motor posturing and prolonged coma are not associated with brain-stem dysfunction but rather with dysfunction of the hemispheres, while absent pupillary and oculocephalic responses are correlated with brain-stem dysfunction alone. However, the accuracy with which MEP data localized human brain-stem or hemispheric dysfunction could not be confirmed by pathological correlation because of low mortality and the small number of autopsies obtained in the patients who died. Therefore, this study was undertaken in an animal model of brain-stem lesion.
Complete brain-stem transections were made at the cervicomedullary junction, the medulla just caudal to the eighth nerve, and at the intercollicular region. All cortical visual evoked potential (VEP) peaks were reduced in amplitude and delayed by each of the brain-stem transections, but none of the peaks was abolished. In spite of brain-stem transection, VEP's can be used to gain information about hemispheric function. Somatosensory (SEP) and auditory cortically generated evoked potentials (AEP) were abolished by these brain-stem transections, but early-latency brain-stem SEP and AEP data could accurately localize specific areas of brain-stem dysfunction caused by the lesions. Observations made on human MEP data seem to be confirmed by these animal experiments. Correlations between human and cat MEP data are discussed.
Improved confidence of outcome prediction in severe head injury
Authors: Narayan Raj K. , Greenberg Richard P. , Miller J. Douglas , Enas Gregory G. , Choi Sung C. , Kishore Pulla R. S. , Selhorst John B. , Lutz Harry A. , Becker Donald P. 
Published: May 2009

✓ An analysis of clinical signs, singly or in combination, multimodality evoked potentials (MEP's), computerized tomography scans, and intracranial pressure (ICP) data was undertaken prospectively in 133 severely head-injured patients to ascertain the accuracy, reliability, and relative value of these indicants individually, or in various combinations, in predicting one of two categories of outcome. Erroneous predictions, either falsely optimistic (FO) or falsely pessimistic (FP), were analyzed to gain pathophysiological insights into the disease process. Falsely optimistic predictions occurred because of unpredictable complications, whereas FP predictions were due to intrinsic weakness of the indicants as prognosticators.
A combination of clinical data, including age, Glasgow Coma Scale (GCS) score, pupillary response, presence of surgical mass lesions, extraocular motility, and motor posturing predicted outcome with 82% accuracy, 43% with over 90% confidence. Nine percent of predictions were FO and 9% FP. The GCS score alone was accurate in 80% of predictions, but at a lower level of confidence (25% at the over-90% level), with 7% FO and 13% FP. Computerized tomography and ICP data in isolation proved to be poor prognostic indicants. When combined individually with clinical data, however, they increased the number of predictions made with over 90% confidence to 52% and 55%, respectively. Data from MEP's represented the most accurate single prognostic indicant, with 91% correct predictions, 25% at the over-90% confidence level. There were no FP errors associated with this indicant. Supplementation of the clinical examination with MEP data yielded optimal prognostic power, an 89% accuracy rate, with 64% over the 90% confidence level and only 4% FP errors.
The clinical examination remains the strongest basis for prognosticating outcome in severe head injury, but additional studies enhance the reliability of such predictions.
Evaluation of CCNU, VM-26 plus CCNU, and procarbazine in supratentorial brain gliomas
Authors: _ _ 
Published: May 2009

✓ This prospective and randomized trial reports the effects of three chemotherapeutic regimens on three different clinical parameters in adults with supratentorial malignant brain gliomas: 1) duration of the interval between surgery and relapse (the “free interval”); 2) total survival time; and 3) rate and length of objective remissions. All patients were irradiated with 5500 to 6000 rads after neurosurgery aimed at an optimum removal.
The administration of VM-26, 60 mg/sq m on Day 1, plus CCNU, 130 mg/sq m on Day 2, repeated every 6 weeks, had no significant effect on the length of the free interval between surgery and relapse. Thus, the median duration of this period was 39 weeks in the group of 61 patients who received adjuvant chemotherapy and 30 weeks in 55 controls without treatment. Neither was the total survival time prolonged by the administration of early chemotherapy. The best prognostic factor for the duration of the free interval and survival was age: patients under 50 years old survived statistically significantly longer.
The rate of the objective remission, defined as a clear-cut clinical improvement persisting 6 weeks after complete discontinuation of steroids, was measured after tumor relapse. In patients who were not previously treated with chemotherapy, CCNU alone or VM-26 plus CCNU produced objective remissions in only 15% of treated patients. Out of 17 cases treated previously by VM-26 plus CCNU, none responded to procarbazine after relapse.
Dandy-Walker syndrome
Authors: Sawaya Raymond , McLaurin Robert L. 
Published: May 2009

✓ A clinical analysis of 23 patients with Dandy-Walker malformation indicates that more than 85% of them were diagnosed at or before 1 year of age, and that the incidence of associated anomalies is approximately 50%, with a 17% incidence for agenesis of the corpus callosum. The significance of the presence of these anomalies is substantiated by the fact that of the seven deaths recorded, six were related to this disease and five were affected by associated anomalies. The high mortality rate (26%) is comparable to that of other series. The differential diagnosis with posterior fossa extra-axial cysts is discussed.
Ten patients were primarily treated with excision of the cyst membrane; all of them required subsequent shunting to control the intracranial pressure, demonstrating the futility of this approach. None of the patients treated with lateral ventricle shunting suffered an upward herniation of the posterior fossa contents, suggesting that combined shunting of the lateral and fourth ventricles is rarely necessary. The technical advantages of posterior fossa shunting alone are outlined. Of the 16 survivors, 14 were assessed for their mental development by means of standard psychometric testing. The results of the intelligence quotient (IQ) scoring have indicated that 71% of the patients have subnormal mental development (IQ < 83). There was no significant relationship between retardation and associated anomalies, although agenesis of the corpus callosum was related to poor intellectual development in the two patients so affected (IQ's of 50 and 73).
Significance of postshunt ventricular asymmetries
Authors: Linder Martin , Diehl Jan T. , Sklar Frederick H. 
Published: May 2009

✓ Ventricular asymmetries after shunt surgery were studied. Right and left ventricular areas from pre and postoperative computerized tomography scans were measured with a computer digitizing technique, and the respective areas were expressed as a ratio. Measurements were made from the scans of 15 hydrocephalic children selected at random. Ages at surgery ranged from 2 weeks to 10.5 years. The time interval between surgery and the postoperative scan ranged from 1 to 101 weeks.
The results indicate a significantly greater decrease in ventricular size on the side of the ventricular shunt catheter. Multiple regression analysis showed no relationship between the magnitude of change in ventricular size and either the patients' ages or the time intervals between surgery and follow-up scans. Possible mechanisms for these postshunt ventricular asymmetries are discussed.
Radiofrequency neurolysis in a clinical model
Authors: Smith Harold P. , McWhorter Joe M. , Challa Venkata R. 
Published: May 2009

✓ Reports differ on which nerve fibers are affected by radiofrequency lesions made in peripheral nerves, some stating that primarily the myelinated delta and unmyelinated C fibers are destroyed, others stating that the destruction affects all sizes of nerve fibers and both myelinated and unmyelinated fibers. This study was designed to confirm one of those two findings, and to study the role that different temperatures might play in determining which fibers are affected.
Radiofrequency lesions (85°C for 2 minutes) were made in dogs by placing a temperature-monitored electrode into the lumbar intervertebral foramina. The dogs were killed at intervals up to 6 weeks after rhizotomy, and the lesions were studied by light and electron microscopy. In all lesions, there was a total loss of unmyelinated fibers and a nearly total loss of myelinated fibers. In other dogs, 2-minute lesions were made at 45°, 55°, 65°, and 75°C, and the lesions examined 1 week later. Again, all sizes and all types of fibers were destroyed.
Effects of hyperbaric oxygen therapy on long-tract neuronal conduction in the acute phase of spinal cord injury
Authors: Higgins Alfred C. , Pearlstein Robert D. , Mullen John B. , Nashold Blaine S. 
Published: May 2009

✓ To study the acute effects of hyperbaric oxygen ventilation (HBO) on long-tract function following spinal cord trauma, the authors employed a technique for monitoring spinal cord evoked potentials (SCEP) as an objective measure of translesion neuronal conduction in cats subjected to transdural impact injuries of the spinal cord. Control animals subjected to injuries of a magnitude of 400 or 500 gm-cm occasionally demonstrated spontaneous return of translesion SCEP within 2 hours of injury when maintained by pentobarbital anesthesia and by ventilation with ambient room air at 1 atmosphere absolute pressure (1 ATA). Animals sustaining corresponding injuries but receiving immediate treatment with HBO at 2 ATA for a period of 3 hours following impact demonstrated variable responses to this treatment modality. Animals sustaining injuries of 400 gm-cm magnitude showed recovery of translesion SCEP in four of five cases, while animals sustaining injuries of 500 gm-cm magnitude responded to HBO treatment by recovery of SCEP no more frequently than did control animals. When the onset of HBO therapy was delayed by 2 hours following impact, there appeared to be no demonstrable protective effect on long-tract neuronal conduction mediated by HBO alone.
The observations suggest that HBO treatments can mediate preservation of marginally injured neuronal elements of the spinal cord long tracts during the early phases of traumatic spinal cord injury. These protective effects may be based upon the reversal of focal tissue hypoxia, or by reduction of tissue edema, or possibly by both of these mechanisms. Increasing magnitudes of impact force and delay in the onset of HBO treatment markedly diminished the protective effects of HBO on long-tract neuronal conduction following traumatic spinal cord injury.
Recurrent retinal ischemia beyond cervical carotid occlusions
Authors: Countee Roger W. , Vijayanathan Thurairasah , Chavis Pamela 
Published: May 2009

✓ Seventeen patients with persistent amaurosis fugax ipsilateral to angiographically documented internal carotid artery (ICA) occlusions in the neck have been treated by the authors over the past 5 years. Complete cerebral arteriography in each case demonstrated that the symptomatic ophthalmic artery was perfused exclusively by the ipsilateral external carotid artery (ECA), which invariably had an obstructive and/or ulcerative lesion at its origin, and/or an adjacent residual “stump” of the occluded ICA. In nine patients, retinal artery branch emboli were visible on funduscopy. One patient had angiographic evidence of intracranial embolization via the ophthalmic artery from the ECA. Although ipsilateral superficial temporal-middle cerebral artery anastomosis in one patient, and endarterectomy of a contralateral carotid stenosis in another patient, failed to relieve symptoms, endarterectomy of the ECA with resection of the “stump” of the occluded ICA effectively terminated symptoms in 10 of 11 patients. Anticoagulant drug therapy promptly abolished symptoms in four nonsurgical patients as well as in two patients with failed operations.
It is concluded that recurrent retinal ischemia beyond cervical carotid occlusions frequently results from microembolism via the ipsilateral ECA. Patients with this mechanism of postocclusion recurrent ischemia can be identified on the basis of clinical history, ophthalmological examinations, and complete cerebral arteriography. Termination of embolic phenomena should be the major treatment goal in these individuals, and ECA endarterectomy is recommended. Anticoagulant drugs are an effective alternative treatment in patients who are poor surgical risks.
Transsphenoidal microsurgery for prolactin-secreting pituitary adenomas
Authors: Faria Miguel A. , Tindall George T. 
Published: May 2009

✓ The authors present the results of transsphenoidal microsurgery in 100 women with the amenorrhea-galactorrhea syndrome caused by pituitary adenomas associated with hyperprolactinemia (prolactinomas). As the surgical results were closely related to the preoperative levels of serum prolactin, the patients were divided into two groups: patients with preoperative prolactin less than 200 ng/ml (Group 1), and those with preoperative prolactin greater than 200 ng/ml (Group 2). The results in Group 1 (72 patients) were significantly better. In this group, 56 (78%) patients regained normal menstrual cycles, and 55 (76%) had return of elevated prolactin levels to normal following surgery. In Group 2 (28 patients), however, only 11 (39%) resumed normal menstrual periods postoperatively, and 13 (46%) had return of elevated prolactin levels to normal. There was good correlation between tumor size and the preoperative level of prolactin. Of the 72 women in Group 1, 58 (81%) had tumors less than 1 cm (microadenomas), whereas of the 28 women in Group 2, only four (14%) had tumors of that size. All patients with visual field deficits preoperatively improved or had a normal visual examination postoperatively; none was made worse by surgery. Four patients (three in Group 2) have required additional surgery and/or irradiation.
In the last six patients of the series, contrast-enhanced coronal computerized tomography slices made with the updated General Electric scanner detected five microadenomas. Considering that a relatively high percentage of sellar polytomograms are negative in patients with proven microadenomas (that is, only 40 of 72 patients in Group 1 had abnormal polytomography), it is likely that sellar polytomography will significantly decrease in importance in the diagnostic work-up of these patients. The authors provide a rationale for transsphenoidal microsurgery in these patients as opposed to other forms of management, such as bromocriptine therapy and irradiation.
Arteriovenous malformations of the medial temporal lobe
Authors: Heros Roberto C. 
Published: May 2009

✓ Arteriovenous malformations (AVM's) of the medial temporal lobe frequently involve the basal ganglia and the thalamus and, for this reason, are commonly judged to be inoperable. However, when the medial involvement is limited to the posterolateral part of the thalamus and to the inferior portion of the basal ganglia lateral to the internal capsule, the lesions may be excised safely. Three patients who underwent successful excision of AVM's of this region are presented. A transcortical surgical approach through the inferior portion of the temporal lobe was used to minimize retraction of the temporal lobe and damage to the optic radiation, and to avoid postoperative dysphasia.
The following neuroradiological criteria indicate that the bulk of the lesion is in the temporal lobe, that only noncritical portions of the basal ganglia and thalamus are involved, and that, therefore, surgical resection is relatively safe: 1) primary supply by the anterior choroidal artery and by laterally oriented branches of the posterior cerebral artery; 2) primary venous drainage into the basal vein of Rosenthal and medial Sylvian veins; 3) projection below the plane of the middle cerebral artery in the lateral carotid arteriogram; 4) projection lateral to the sweep of the posterior cerebral artery in the anteroposterior or Towne's view of the vertebral angiogram; and 5) demonstration of an intratemporal clot or intraventricular blood by computerized tomography.