bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental investigation on the spinal cord evoked injury potential
Authors: Schramm Johannes , Krause Rolf , Shigeno Taku , Brock Mario
Published: May 2009

✓ Averaged somatosensory evoked potentials from the epidural space in response to sciatic nerve stimulation were recorded in bipolar and common reference mode in cats following various types of injury. An investigation was conducted on the development and properties of the spinal evoked response recorded from the center of the injury site, designated here as the “spinal cord evoked injury potential.” Typically it is a two-peak monophasic positive potential, approximately 40 msec in duration, with a slight negative afterwave. With increasing distance from the site of injury, its amplitude rapidly decreases, whereas latency remains constant. The common reference recording technique resulted in an earlier and better demonstration of the evoked injury potential, especially when it was transitory or incomplete. When impairment of conduction developed gradually, the evoked injury potential developed gradually too. In serial recordings along the spinal cord axis, the transition from a normal triphasic to a monophasic evoked injury potential allowed a precise localization of the lesion.

These data suggest that the diagnostic value of intraoperative spinal cord monitoring may be increased by adopting a technique that incorporates several epidural recordings with a common reference recording technique. The spinal cord evoked injury potential seems to be a more sensitive indicator of spinal cord injury than the cortical evoked potential. The findings are discussed in the light of the presently developing spinal cord monitoring techniques.
Hypervolemic hemodilution in experimental focal cerebral ischemia
Authors: Wood James H. , Simeone Frederick A. , Fink Eugene A. , Golden Michael A.
Published: May 2009

✓ Cerebrovascular and cardiac alterations evoked by intravascular volume expansion with low molecular weight dextran (LMD, molecular weight 40,000), an advocated adjunct in the clinical prevention or therapy of acute stroke and cerebral vasospasm, were studied in splenectomized dogs. Clipping of the right distal internal carotid artery and the proximal middle cerebral artery (MCA) in eight dogs decreased regional cortical blood flow (rCoBF) by 58% without changing cardiac output (CO), and caused 10% ± 5% (SE) hemispheric infarction. Ten other dogs underwent similar cerebral arterial occlusion and were infused twice with LMD within 2 hours; each infusion equaled 20% of the respective dog's total blood volume. Both CO and rCoBF in the territory of the occluded MCA increased significantly by 119% ± 13% and 42% ± 6%, respectively, following the two LMD infusions. Although the mean arterial blood pressure was unaltered, the hematocrit decreased significantly and the intracranial pressure (ICP) increased significantly. The mean hemispheric infarction in these 10 treated dogs was 4% ± 2%. Another nine dogs underwent arterial manipulation without clipping. Two hemodiluting LMD infusions, similar to those in the 10 dogs, significantly elevated CO and ICP but not rCoBF. These data suggest that hypervolemic hemodilution with LMD effectively elevates collateral perfusion to ischemic regions of brain distal to occluded MCA segments and concomitantly raises the CO and ICP.
Mutism as a consequence of callosotomy
Authors: Sussman Neil M. , Gur Ruben C. , Gur Raquel E. , O'Connor Michael J.
Published: May 2009

✓ Transient mutism has been reported following commissurotomy and callosotomy. The cause for this mutism is unknown. A case of mutism following callosotomy is presented, and the preoperative and postoperative data on neurological, physiological, and psychological functioning are discussed. The data suggest that the mutism is not caused by general intellectual deterioration, cortical lesion, or peripheral damage affecting speech production. The syndrome may result from severing interhemispheric connections in cases where both hemispheres are required for speech production.
Proatlantal intersegmental artery and trigeminal artery associated with an aneurysm
Authors: Tanaka Yuichiro , Hara Hideaki , Momose Genki , Kobayashi Shigeru , Kobayashi Shigeaki , Sugita Kenichiro
Published: May 2009

✓ A case of coexisting proatlantal intersegmental artery and primitive trigeminal artery is described. These anomalies were incidental findings in a patient with hemiparesis due to occlusion of the middle cerebral artery. The primitive trigeminal artery had an asymptomatic aneurysm at its origin from the internal carotid artery.
Deflation of metrizamide-filled balloon used to occlude a carotid-cavernous fistula
Authors: Leipzig Thomas J. , Mullan Sean F.
Published: May 2009

✓ A carotid-cavernous fistula was occluded by a detachable latex balloon. Because of technical problems, the contrast-filled balloon was left in a precarious position in the ostium of the fistula. Premature deflation of the balloon would have resulted in intra-arterial migration of the device. Approximately 1 week is required for the balloon to become secured in place by fibrous attachment to the vascular wall. For success, if the ligature is adequate, a detachable Debrun balloon should remain inflated for this period of time. The deflation process was monitored radiographically in this patient. The balloon remained inflated for at least 2 weeks. A short summary of the experience with deflation of various contrast-containing balloon devices in the treatment of carotid-cavernous fistulas is given. Metrizamide may be the best contrast agent for use in these devices.
Calcification of the ligamentum flavum of the cervical spine
Authors: Iwasaki Yoshinobu , Akino Minoru , Abe Hiroshi , Tsuru Mitsuo , Tashiro Kunio , Miyasaka Kazuo , Kaneda Kiyoshi , Isu Toyohiko , Ito Terufumi
Published: May 2009

✓ Four cases of calcification of the cervical ligamentum flavum are reported, all in women over 60 years of age. Neurological findings were not significantly different from those of other cervical compressive diseases. Among radiological examinations, computerized tomography was the most valuable diagnostic tool. Calcification might have been induced by the degeneration or abnormal nutritional state of the ligamentum flavum. Endocrine abnormalities and inflammatory processes might also have been contributory factors.
The laser in neurological surgery
Authors: Edwards Michael S. B. , Boggan James E. , Fuller Terry A.
Published: May 2009

✓ The use of lasers in neurosurgical procedures has received a great deal of attention recently. Surgical use of lasers has been viewed with suspicion and skepticism, probably because of (justified) apprehensions about the misuse of lasers in early work and about the ways in which laser light affects tissues, and a lack of understanding of the basic physics and practical operation of lasers. The authors review the physics, biophysics, experimental findings, and operative use of lasers in current neurosurgical practice, and discuss briefly their experience gained in over 150 neurosurgical procedures using the carbon dioxide and argon surgical lasers.
Interpretation of nuclear magnetic resonance tomograms of the brain
Authors: Go K. Gwan , van Dijk Piet , Luiten André L. , Brouwer-van Herwijnen Addie A. , van der Leeuw Ijsbrand C. L. , Kamman Richard L. , Vencken Louk M. , Wilmink Jan , Berendsen Herman J. C.
Published: May 2009

✓ Nuclear magnetic resonance tomography is an imaging method based on the magnetic resonance behavior of protons, as they occur predominantly in tissue water or in fatty acids. This behavior, as characterized by the relaxation times T1 and T2, is determined by the chemical and physical environment of the protons. The relaxation properties of the tissue can be accentuated by selection of the appropriate pulse sequence. Interpretation of the images requires an understanding of the principles of the technique with which the relaxation times are expressed in the images, and acquaintance with the composition of the tissue in terms of relaxation properties (as in computerized tomography, tissue composition is expressed as attenuation coefficients).
Pituitary adenomas with onset during puberty
Authors: Fraioli Bernardo , Ferrante Luigi , Celli Paolo
Published: May 2009

✓ From a series of 207 patients with pituitary adenoma operated on by microsurgical technique from 1973 to February, 1982, the cases of nine young people whose symptoms had appeared between the ages of 11 and 15 years are presented. The most important data are that all the children were pubertal and that in seven the tumor was, or later became, invasive. By contrast, the tumor was enclosed in eight of nine other patients whose symptoms manifested between the ages of 16 and 20 years, and in 152 of the remaining 189 patients whose symptoms appeared after the age of 20 years. Considering the gravity of the disease treated, the results in this series may be termed encouraging. The treatment was multidisciplinary: starting with surgery, followed by radiotherapy, endocrine replacement therapy, and, in adenomas secreting prolactin and/or growth hormone, medical therapy with bromocriptine. The divergence between authors on the subject of childhood adenomas, especially as to whether they are more often invasive or enclosed, could be overcome, at least in part, if the term “pediatric age” were unequivocally defined and if there were an agreed distinction between puberty and childhood on the one hand and puberty and adolescence on the other.
Intraventricular morphine for control of pain in terminal cancer patients
Authors: Lobato Ramiro D. , Madrid Jose L. , Fatela Lorenza V. , Rivas Juan J. , Reig Enrique , Lamas Eduardo
Published: May 2009

✓ Satisfactory control of intractable pain has been achieved in 17 terminal cancer patients by injecting small doses of morphine into the lateral cerebral ventricle via an Ommaya reservoir. Pain relief together with a favorable behavioral response was obtained without interference with other sensory modalities, noticeable physical changes, or side effects annoying or severe enough for the patient to discontinue therapy. Eleven patients developed tolerance, but this phenomenon does not require withdrawal of treatment. Chronic intraventricular morphine administration can be safely performed on an outpatient basis, and results in control of midline, bilateral, and diffuse pain associated with orofacial and disseminated cancer. However, this experience is preliminary and further clinical trials are needed to determine the place of this method of therapy in the management of chronic pain.
Improved survival in cases of intracranial ependymoma after radiation therapy
Authors: Salazar Omar M. , Castro-Vita Hernan , VanHoutte Paul , Rubin Philip , Aygun Cengiz
Published: May 2009

✓ A publication from the University of Rochester Cancer Center in 1975 suggested an improvement in the survival time of patients with intracranial ependymomas in whom an aggressive postoperative radiation therapy approach had been adopted. The regimen was tailored to the aggressiveness and spread patterns of these tumors and therefore considered the patient's age, tumor histopathology and location, and status of the subarachnoid space and cerebrospinal fluid (CSF). The authors proposed using whole brain (WB) fields for all patients with low-grade supratentorial tumors, and WB with cervical cord field extensions for low-grade infratentorial tumors if either group had no CSF or subarachnoid evidence of spinal metastases. They also proposed using craniospinal irradiation for all patients with high-grade ependymomas (regardless of location) or with low-grade infratentorial tumors with positive CSF or subarachnoid findings of spinal metastases. Recommended doses were as follows: 4500 rads to the whole brain, 5500 rads to the primary tumor volume, and 3000 to 4000 rads to the spine, depending on its subarachnoid status. Children aged 3 years or under were to receive 80% of these doses and more protracted daily treatments.

Analysis of the updated experience indicates that in 51 patients treated with this approach these criteria have yielded a beneficial and consistent increase in the survival time. A 69% 10-year survival rate has been observed (75% for low-grade and 67% for high-grade ependymomas). A multifactorial analysis of survival by prognostic factors and by grouping of prognostic factors, analysis of failures, autopsy findings, and quality of survival is presented and discussed.
Differential diagnosis between ventriculitis and fourth ventricle cyst in neurocysticercosis
Authors: Salazar Abelardo , Sotelo Julio , Martinez Hector , Escobedo Francisco
Published: May 2009

✓ The fourth ventricle is frequently affected in patients with cysticercosis of the central nervous system, due either to a large cyst occluding the cavity or to granular ependymitis (ventriculitis) as a consequence of diffuse inflammation within the intraventricular and subarachnoid spaces. In some cases, the differential diagnosis between these two forms of neurocysticercosis is difficult to make, even after special radiological procedures. It is important to establish the correct diagnosis, since a surgical approach is beneficial only when the fourth ventricle is obstructed by a large cyst. In this paper, the clinical differences between fourth ventricle cysts and ventriculitis are presented in 16 patients with neurocysticercosis who were subjected to surgical exploration of the posterior fossa. Patients with a large cyst occluding the fourth ventricle had a short evolution of signs and symptoms, Bruns' syndrome, and discrete or no inflammatory reaction in the cerebrospinal fluid (CSF). Patients with ventriculitis generally had a longer duration of signs and symptoms, Parinaud's syndrome, a consistently positive complement fixation test to cysticerci, and more cells and proteins in the CSF. The clinical picture and ancillary studies can give the precise diagnosis in most patients before surgical exploration is performed.
Pituitary apoplexy following closed head trauma
Authors: Holness Renn O. , Ogundimu Fadegbola A. , Langille Roland A.
Published: May 2009

✓ The authors report a case of chiasmal compression resulting from hemorrhage into a pituitary adenoma following minor head trauma. The adenoma was still confined to the pituitary fossa and only in retrospect had caused any endocrine effects prior to the accident. The diagnosis in this case was established by computerized tomography, angiography, subsequent surgery, and pathological examination of the specimen. There was significant but partial recovery of vision following surgery.
Ruptured berry aneurysm of the anterior ethmoidal artery associated with bilateral spontaneous internal carotid artery occlusion in the neck
Authors: Tasker Ronald R.
Published: May 2009

✓ A unique case is described of subarachnoid hemorrhage from a ruptured berry aneurysm of the right anterior ethmoidal artery, and its pathogenesis is discussed. The literature suggests an increased incidence of posterior circulation aneurysms in moyamoya disease, of contralateral anterior circulation aneurysms in agenesis of the carotid artery, and of aneurysms at various sites in spontaneous and iatrogenically acquired obstructions of the internal carotid artery. In addition to congenital anomalies of the vessel wall and systemic hypertension, increased regional blood flow should be regarded as an important factor in the generation of berry aneurysms.
Extracerebral neural tissue mass in the middle cranial fossa extending into the oropharynx in a neonate
Authors: Wakai Susumu , Nakamura Kimiaki , Arai Toshimoto , Nagai Masakatsu
Published: May 2009

✓ The authors report the case of a newborn baby girl who had a large extracerebral neural tissue mass in the right middle cranial fossa which extended into the oropharynx through an enlarged foramen ovale. The surgical specimen comprised various kinds of neural tissue, including primitive neuroepithelium, mature as well as immature neurons and glia, myelinated fibers, ependyma, choroid plexus, ocular pigmented epithelium, and a number of calcospherites. The mass was partially covered by its own leptomeninges. The question of whether this mass is a true neoplasm or a heterotopia is discussed.
Anterior inferior cerebellar artery aneurysm
Authors: Nishimoto Akira , Fujimoto Shunichiro , Tsuchimoto Shoji , Matsumoto Yuzo , Tabuchi Kazuo , Higashi Tohru
Published: May 2009

✓ Three cases of aneurysms of the anterior inferior cerebellar artery are reported. Two of the aneurysms were located in the cerebellopontine angle and one in the ventral portion of the pons. Through a suboccipital craniectomy, neck clipping was perfomed on one aneurysm, neck ligation on another, and coating on the third. A discussion of the surgical procedures and complications includes a review of previous reports.
Adult aqueductal stenosis presenting with fluctuating hearing loss and vertigo
Authors: Barlas Orhan , Gökay Hüsameddin , Turantan M. İnan , Başerer Nermin
Published: May 2009

✓ Two cases of aqueductal stenosis presenting with fluctuating hearing loss, tinnitus, and vertigo are presented. Audiovestibulometric assesment of both cases disclosed the characteristic pattern of disorder of the membranous inner ear. Non-tumoral aqueductal stenosis was demonstrated by computerized tomography in one case and by positive contrast ventriculography in the other. Shunting procedures of the cerebrospinal fluid resulted in resolution of inner ear dysfunction in both patients.
Repair of lumbosacral myelomeningoceles with double Z-rhomboid flaps
Authors: Cruz Norma I. , Ariyan Stephan , Duncan Charles C. , Cuono Charles B.
Published: May 2009

✓ The authors describe a double Z-rhomboid technique for the closure of large lumbosacral myelomeningocele defects. After the dorsally displaced neural tissue has been reduced into the vertebral canal and a watertight closure of the dura lining the sac has been achieved, the skin defect is surgically converted to the shape of a rhombus. Equilateral Z-plasty flaps are elevated at the sides of the rhombus and transposed across the defect to secure wound closure. A successful experience with 10 consecutive cases of lumbosacral myelomeningoceles repaired with this technique is reported.
Operative repair of lumbosacral myelomeningocele
Authors: Cheek William R. , Laurent John P. , Cech David A.
Published: May 2009

✓ A technique is described for closure of lumbosacral myelomeningoceles. The pathological anatomy of these lesions is examined, and the junction of the skin and dura is identified as the “junctional zone.” This zone permits maximal preservation of the available dura for watertight closure after operative dissection. The junctional zone also serves as an anchor for traction sutures, permitting skin closure without tension. Seventy consecutive repairs have been completed by the authors without significant complications. There have been no instances of cerebrospinal fluid leaks, meningitis, or wound dehiscence. In all cases the repair was carried out rapidly and in a single stage.
Cognitive outcome and early indices of severity of head injury
Authors: Alexandre Alberto , Colombo Federico , Nertempi Paola , Benedetti Antonio
Published: May 2009

✓ Neuropsychological outcome of 100 patients with severe head injuries is correlated with their clinical condition on admission. The aim of this paper is to estimate the reliability of several early indices of brain damage severity in formulating a prognosis. Both the Glasgow Coma Scale and the neurological syndrome involved appeared to be highly reliable in this respect. The duration of coma and of posttraumatic amnesia was not as significant. Since these two parameters were assessed when reviewing the cases, they have to be considered only as retrospective judgments. The findings emphasized the importance of reflex ocular motility and the value of recording eletroencephalographic (EEG) activity, particularly EEG sleep patterns. The relationship between rapid eye movement sleep impairment and cognitive defects was highly significant. Analysis of surgical observations demonstrated that purely compressive expanding lesions were not as harmful as parenchymal damage. Of paramount importance was the time lapse between injury and surgery, since secondary lesions may develop and affect cerebral areas that are involved both in sleep organization and in memory functions.
Outcome from severe head injury related to the type of intracranial lesion
Authors: Lobato Ramiro D. , Cordobes Francisco , Rivas Juan J. , de la Fuente Marina , Montero Angel , Barcena Alejandro , Perez Carlos , Cabrera Antonio , Lamas Eduardo
Published: May 2009

✓ The influence of the type of intracranial lesion on the final outcome in a consecutive series of 277 severely head-injured patients was analyzed. Patients were studied with computerized tomograpy (CT) and underwent continuous measurement of intracranial pressure. They received identical treatment according to a standardized protocol. Outcome of patients with either epidural hematoma (38 cases), subdural hematoma (56 cases), brain contusion (87 cases), or diffuse brain damage (96 cases) was rather heterogeneous, and serial CT scanning allowed the authors to outline eight consistent anatomical patterns in the whole series which have stronger prognostic significance than the four major lesion categories mentioned above. Patients with pure extracerebral hematoma (19 cases), single brain contusion (45 cases), general brain swelling (41 cases), and normal CT scans (28 cases) had a significantly better outcome than patients developing acute hemispheric swelling after operation for a large extracerebral hematoma (27 cases), patients with multiple brain contusion, either unilateral or bilateral (74 cases), and patients with diffuse axonal injury (43 cases). These anatomical patterns are interesting because, in addition to having clinical and physiopathological significance, they provide useful prognostic information and facilitate improved therapeutic decision-making in severely head-injured patients.
Mortality following penetrating craniocerebral injuries
Authors: Rish Berkley L. , Daniel Dillon James , Weiss George H.
Published: May 2009

✓ A population of 1127 men with penetrating craniocerebral injuries who were alive 1 week after their injuries has been followed for 15 years. During this time, 90 deaths (8%) occurred. Most of the deaths occurred early in the 1st year after trauma and were secondary to the direct effects of brain injury or the sequelae of coma. Complications, particularly infections, were significant mortality factors. Coma was the best prognostic guideline. Posttraumatic epilepsy was not related to mortality except for the risks accompanying each ictus. The population now appears to be approaching the actuarial norm of their peers.
Sensory cortical tongue representation in man
Authors: Picard Claude , Olivier André
Published: May 2009

✓ Extensive data on cortical tongue representation were analyzed in 100 patients who underwent craniotomy and cortical mapping by electrical stimulation for surgical treatment of epilepsy. As noted in the literature, the tongue is extensively represented within the central nervous system with a highly organized sensorimotor system and the data from this study corroborate a large cortical representation of the human tongue over the postcentral gyrus. The tongue was found to have a clear somatotopic organization over the postcentral area and to be represented bilaterally to a significant degree. Furthermore, the tongue appears to have an asymmetrical sensory cortical representation, as cerebral dominance for speech is more extensively represented on the dominant hemisphere. Cortical tongue mapping has proved extremely useful in determining the point of junction of the central and Sylvian sulci, a crucial landmark during surgical cortical resections.
Adverse impact of a calcium entry-blocker (verapamil) on intracranial pressure in patients with brain tumors
Authors: Bedford Robert F. , Dacey Ralph , Winn H. Richard , Lynch Carl
Published: May 2009

✓ In order to examine the effects of verapamil on intracranial pressure (ICP) in patients with compromised intracranial compliance, five hypertensive patients with supratentorial tumors were given verapamil, 5 mg intravenously, at the time of anesthesia induction. Within 4 minutes, ICP increased 67% from 18 ± 4 mm Hg (standard error) to 27 ± 5 mm Hg (p < 0.05), whereas mean arterial pressure decreased 20% from 111 ± 7 mm Hg to 89 ± 4 mm Hg (p < 0.05), and cerebral perfusion pressure (CPP) decreased 33% from 93 ± 11 mm Hg to 62 ± 6 mm Hg (p < 0.05). The increases in ICP responded promptly to hyperventilation and intravenous lidocaine (1.5 mg/kg). A control group of five hypertensive patients with supratentorial tumors received the same anesthetic agents without verapamil. In this group, ICP and CPP were unchanged. The authors conclude that calcium entry-blockers, such as verapamil, should be avoided in patients with compromised intracranial compliance unless ICP is being monitored and proper therapy for intracranial hypertension can be rapidly instituted.
The influence of systemic arterial pressure and intracranial pressure on the development of cerebral vasogenic edema
Authors: Durward Quentin J. , Maestro Rolando F. Del , Amacher A. Loren , Farrar J. Keith
Published: May 2009

✓ The influence of intracranial pressure (ICP), systemic arterial pressure (SAP), and cerebral perfusion pressure (CPP) upon the development of vasogenic cerebral edema is largely unknown. To study their relationship, the authors have produced an osmotic disruption of the blood-brain barrier unilaterally in rabbits by injecting 1 cc/kg of 2M NaCl into the left internal carotid artery. The amount of vasogenic edema produced was assessed by quantitation of the extravasation of Evans blue dye into the area of maximum blood-brain barrier breakdown by means of optical densitometry following formamide extraction. The ICP was measured using a cisterna magna catheter into which mock cerebrospinal fluid could be infused at a predetermined pressure. The SAP was controlled by exsanguination from a femoral artery catheter.

In 18 animals in which blood pressure was not controlled, no significant relationship between the ICP and the degree of Evans blue dye extravasation was noted. In these animals, however, a direct relationship between CPP (defined as mean arterial pressure minus mean ICP) and extravasation of Evans blue dye was found (correlation coefficient 0.630; p < 0.001). When ICP was held constant at 0 to 5 mm Hg in another group of 16 animals and different levels of blood pressure were produced by exsanguination, a significant direct relationship between extravasation of Evans blue dye and the SAP was found (correlation coefficient 0.786; p < 0.001). In a third group of 20 animals, the blood pressure was held constant at 90 to 100 mm Hg and the ICP was varied between 0 and 75 mm Hg. There was a highly significant result indicating increasing Evans blue dye extravasation with lower levels of ICP (p < 0.001). Cerebral blood flow determinations by the hydrogen clearance method indicated loss of autoregulation in all animals in the areas of brain injured by intracarotid hypertonic saline.

These results indicate that high SAP and low ICP (that is, a large CPP) promote Evans blue dye extravasation in this model of blood-brain barrier disruption. This finding has implications for the management of patients with vasogenic edema.
Analysis of the cerebrospinal fluid pulse wave in intracranial pressure
Authors: Cardoso Erico R. , Rowan Jack O. , Galbraith Sam
Published: May 2009

✓ The configuration of the intracranial pressure (ICP) pulse wave represents a complex sum of various components. Amplitude variations of an isolated component might reflect changes in a specific intracranial structure. Fifteen awake patients suffering from hydrocephalus, benign intracranial hypertension, or head injury underwent ICP monitoring through a ventricular catheter and were subjected to three standardized maneuvers to alter the intracranial dynamics: head elevation, voluntary hyperventilation, and cerebrospinal fluid (CSF) withdrawal. A 12° head elevation and fractionated CSF withdrawal caused a mild ICP drop and a proportionate amplitude reduction of all the wave components. Voluntary hyperventilation caused a comparable fall in ICP, and a disproportionate reduction in the amplitude of the wave components, especially the P2 component. It is postulated that the decrease in amplitude of the P2 component reflects the reduction of the cerebral bulk caused by hyperventilation. Head elevation and CSF withdrawal caused a decrease of global ICP but no specific changes in any intracranial structure, and consequently the configuration of the pulse wave remained unchanged. The establishment of relationships between anatomical substrate and particular wave components is promising since potentially it could be useful for monitoring conditions such as vasoparalysis, impaired cerebrovascular reactivity, and cerebral edema.
Mannitol causes compensatory cerebral vasoconstriction and vasodilation in response to blood viscosity changes
Authors: Muizelaar J. Paul , Wei Enoch P. , Kontos Hermes A. , Becker Donald P.
Published: May 2009

✓ There is no proof that osmotic agents such as mannitol lower intracranial pressure (ICP) by decreasing brain water content. An alternative mechanism might be a reduction in cerebral blood volume through vasoconstriction. Mannitol, by decreasing blood viscosity, would tend to enhance cerebral blood flow (CBF), but the cerebral vessels would constrict to keep CBF relatively constant, analogous to pressure autoregulation. The cranial window technique was used in this study to measure the pial arteriolar diameter in cats, together with blood viscosity and ICP changes after an intravenous bolus of 1 gm/kg of mannitol. Blood viscosity decreased immediately; the greatest decrease (23%) occurred at 10 minutes, and at 75 minutes there was a “rebound” increase of 10%. Vessel diameters decreased concomitantly, the largest decrease being 12% at 10 minutes, which is exactly the same as the 12% decrease in diameter associated with pronounced hyperventilation (PaCO2 30 to 19 mm Hg) in the same vessels; at 75 minutes vessel diameter increased by 12%. With hyperventilation, ICP was decreased by 26%; 10 minutes after mannitol was given, ICP decreased by 28%, and at 75 minutes it showed a rebound increase of 40%. The correlation between blood viscosity and vessel diameter and between vessel diameter and ICP was very high. An alternative explanation is offered for the effect of mannitol on ICP, the time course of ICP changes, the “rebound effect,” and the absence of influence on CBF, all with one mechanism.
Secondary spinal canal stenosis associated with long-term ventriculoperitoneal shunting
Authors: Kobayashi Akira , Hashi Kazuo
Published: May 2009

✓ Secondary changes in the cervical spine were studied in 18 cases with long-term ventriculoperitoneal (VP) shunting. Significant decreases in the anteroposterior diameter of cervical spinal canal and interpedicular distance were noted in patients who had had a VP shunt placed before 2 years of age and in whom sustained low intracranial pressure persisted for a long time, as evidenced by early closure of the cranial sutures or thickening of the cranial bones.
Carotid body tumors managed with preoperative embolization
Authors: Borges Lawrence F. , Heros Roberto C. , DeBrun Gerard
Published: May 2009

✓ Two patients with large vascular carotid body tumors underwent preoperative intravascular embolization of the major arterial feeders. The tumor vascularity was reduced markedly, and complete surgical extirpation was accomplished without difficulty. The literature on carotid body tumors is briefly reviewed. The role of preoperative embolization in the treatment of these difficult tumors is emphasized.
Calcified pituitary adenoma associated with severe hyperprolactinemia
Authors: Carapella Carmine Maria , Pompei Paolo , Mastrostefano Roberto , Occhipinti Emanuele , Rocco Antonio , Falaschi Paolo
Published: May 2009

✓ A patient with a completely calcified chromophobe adenoma is reported. Endocrine evaluation revealed very high prolactin levels. Such extensive calcifications in prolactin-secreting adenomas are extremely rare. The possible pathogenetic mechanisms of this association are discussed.
Tuberculoma mimicking a pinealoma
Authors: Whittle Ian R. , Allsop John L. , Besser Michael
Published: May 2009

✓ Computerized tomography (CT) revealed obstructive hydrocephalus and a pineal mass in a 14-year-old girl who presented with headaches and a Parinaud's syndrome. Although there was no major evidence of extracranial tuberculosis, and cerebrospinal fluid obtained during third ventriculostomy contained no leukocytes, suboccipital transtentorial biopsy of the lesion revealed it to be a tuberculoma. Serial CT scans showed resolution of the lesion following subtotal resection and antituberculous therapy. The implications of this case with regard to difficulties in the diagnosis of cerebral tuberculoma and the management of pineal region tumors are discussed.
Neonatal intracranial teratoma
Authors: Ventureyra Enrique C. G. , Herder Stephanie
Published: May 2009

✓ The authors report the successful total excision of an intracranial teratoma in a neonate. The pathology of this rare tumor and its prognosis in relation to the maturity of individual cell lines is discussed. A review of the previous operation experience in the neonatal age group shows that radical surgical excision of the tumor has seldom been attempted. There are no reported survivors with normal neurological development. The clinical presentation, preoperative evaluation, and operative management are discussed. Emphasis is laid on intensive supportive care in the perioperative period. The difficulty in predicting a benign or malignant course in these tumors justifies extreme caution in making a prognosis and demands careful follow-up supervision. Reoperation is indicated for recurrent benign tumors; malignant germ-cell tumors may respond to combined irradiation and chemotherapy.
Laser-induced dorsal root entry zone lesions for pain control
Authors: Levy Walter J. , Nutkiewicz Alan , Ditmore Q. Michael , Watts Clark
Published: May 2009

✓ Dorsal root entry zone lesions have been documented as effective for control of intractable pain in patients with brachial plexus avulsion or severe spinal cord injury. These lesions are usually made with the radiofrequency technique. The authors report three cases in which the CO2 laser was used as an alternative means of making the lesions. This latter technique provided effective pain relief in two of the patients and was efficient to use. It was noted that the presence of overlying scar tissue can be deceptive in judging the depth of the lesion made with the laser. The CO2 laser provided a means of producing controlled spinal cord lesions which may be more precise than the radiofrequency method.
Regrowth of diastematomyelic bone spur after extradural resection
Authors: Pang Dachling , Parrish Rob G.
Published: May 2009

✓ Complete regrowth of a diastematomyelic bone septum producing progressive neurological deficits was found in a 15-year-old boy who had a previous extradural resection of a similar bone spur with the dural sleeve left untouched. This case and two similar cases in the literature documenting continued neurological deterioration after extradural removal of septum emphasize the need for resection of the dural sleeve along with the bone septum if adequate relief of tethering is expected. The capability of the septum to regenerate may be due to the persistence of residual mesenchymal cells associated with the embryogenesis of the midline septum.
Diverticulum of the lateral ventricle causing cerebellar ataxia
Authors: Wakai Susumu , Narita Junichi , Hashimoto Kazumasa , Nagai Masakatsu
Published: May 2009

✓ A case of ventricular diverticulum causing cerebellar ataxia is presented. Computerized tomography clearly demonstrated the aperture of the diverticulum in the medial wall of the trigone and its extension into the posterior fossa. The diverticulum regressed and the cerebellar ataxia disappeared after placement of a ventriculoperitoneal shunt.
Calcium channel antagonist binding sites labeled by 3H-nimodipine in human brain
Authors: Peroutka Stephen J. , Allen George S.
Published: May 2009

✓ In vitro binding of 3H-nimodipine to human brain membranes is demonstrated in this study. This binding was specific and saturable, and had an apparent affinity constant (KD) of 0.27 nM. The maximal number of binding sites for 3H-nimodipine was 5.8 pmoles/gm wet weight of human frontal cortex. The binding was shown to be dependent on calcium, with half-maximal stimulation obtained at 3 × 10−5 M CaCl2. Other 1,4-dihyropyridine calcium antagonists were shown to be competitive antagonists of 3H-nimodipine binding. In contrast, the calcium antagonists, verapamil and diltiazem, had complex interactions with 3H-nimodipine binding. These results represent the first identification of 3H-calcium antagonist binding sites in human brain, and they confirm that various calcium antagonist drugs may differ with respect to both their potency and their molecular site of action.
Cerebral and cardiovascular responses to changes in head elevation in patients with intracranial hypertension
Authors: Durward Quentin J. , Amacher A. Lorne , Del Maestro Rolando F. , Sibbald William J.
Published: May 2009

✓ To establish if an optimum level of head elevation exists in patients with intracranial hypertension, the authors examined changes in intracranial pressure (ICP), systemic and pulmonary pressures, systemic flows, and intrapulmonary shunt fraction with the patient lying flat, and then with the head elevated at 15°, 30°, and 60°. Cerebral perfusion pressure (CPP) was calculated. The lowest mean ICP was found with elevation of the head to 15° (a fall of −4.5 ± 1.6 mm Hg, p < 0.001) and 30° (a fall of −6.1 ± 3.5 mm Hg, p < 0.001); the CPP and cardiac output were maintained. With elevation of the head to 60°, the mean ICP increased to −3.8 ± 9.3 mm Hg of baseline, while the CPP decreased −7.9 ± 9.3 mm Hg (p < 0.02), and the cardiac index also fell −0.25 ± 0.28 liters/min/sq m (p < 0.01). No significant change in filling pressures, arterial oxygen content, or heart rate was encountered at any level of head elevation. Therefore, a moderate degree (15° or 30°) of head elevation provides a consistent reduction of ICP without concomitant compromise of cardiac function. Lower (0°) or higher (60°) degrees of head elevation may be detrimental to the patient because of changes in the ICP, CPP, and cardiac output.
Effect of mannitol and furosemide on blood-brain osmotic gradient and intracranial pressure
Authors: Pollay Michael , Fullenwider Charles , Roberts P. Alex , Stevens F. Alan
Published: May 2009

✓ The effect of mannitol (1.0 gm/kg) and furosemide (0.7 mg/kg), alone and in combination, on the blood-brain extracellular fluid and cerebrospinal fluid (CSF) osmotic gradient, elevated intracranial pressure (ICP), CSF and serum osmolality, and urine output was studied in 26 mongrel dogs. Mannitol and furosemide, when used together, produced a greater (62.4% versus 56.6%) and more sustained (5 hours versus 2 hours) fall in ICP than mannitol alone. This correlated with a prolongation of the reversal of the blood-brain osmotic gradient (−3.4 to +38.5 mOsm/kg) and a rate of urine formation 15 times control values. There was a transient but not significant fall in serum Na+ with the combined treatment, but the arterial pressure did not vary from pretreatment levels. The results from this present study suggest that the distal loop diuretics in a dose of less than 1.0 mg/kg act synergistically with mannitol by causing preferential excretion of water over solute in the renal distal tubule, and thereby sustaining the osmotic gradient initially established by the mannitol infusion. It is possible, but unlikely in the doses used, that the additive effect of furosemide on reducing ICP in the presence of mannitol is due to interference with CSF formation or Na+ and H2O movement across the blood-brain barrier.
Intracerebral toxoplasmosis in patients with acquired immune deficiency syndrome
Authors: Handler Michael , Ho Victor , Whelan Margaret , Budzilovich Gleb
Published: May 2009

✓ The acquired immune deficiency syndrome (AIDS) is a recently described T-cell deficiency predisposing patients to a spectrum of opportunistic infections, Kaposi's sarcoma, and other neoplasms. It appears primarily among homosexual males and intravenous drug abusers, but is now being observed in other groups as well. The authors describe six adult patients with AIDS who developed intracranial toxoplasmosis. In four patients, diagnosis was made by brain biopsy, and in one by serology. These patients received a 90-day course of therapy with sulfadiazine, pyrimethamine, or both when tolerated, and improved neurologically. In one patient, the brain biopsy was nondiagnostic and the organism was identified at autopsy. On computerized tomographic and pathological follow-up studies the organism appeared to be eradicated by therapy. Early aggressive diagnostic study and prompt institution of therapy are imperative for reversal of neurological deficits. Despite cure of toxoplasmosis, the prognosis in patients with AIDS is poor; the mortality in this series was 67%. Isolation precautions should be taken by those caring for such patients.
Successful treatment of a group of spinal cord arteriovenous malformations by interruption of dural fistula
Authors: Oldfield Edward H. , Di Chiro Giovanni , Quindlen Eugene A. , Rieth Kenneth G. , Doppman John L.
Published: May 2009

✓ As demonstrated by selective spinal cord arteriography, over 80% of spinal cord arteriovenous malformations (AVM's) occupy a predominantly extramedullary position. Current therapy frequently requires surgical stripping of the long dorsal intradural vessel(s) from the underlying spinal cord over many cord segments. The authors report six patients with a dural arteriovenous fistula fed by a cluster of abnormal epidural arteries. These vessels, which surrounded and were embedded into the dural covering of a thoracic nerve root, drained into a long sinuous intrathecal paramedullary vein(s). The angiographic and surgical appearance of the intradural component of these lesions was identical to that of lesions previously classified as Type I AVM's of the spinal cord. All patients had symptoms and signs of myelopathy. In five patients, surgery was limited to coagulation and excision of the extradural vessels and division of the intradural arterialized vein. Progressive improvement began within days following surgery. No residual abnormality was demonstrated by postoperative selective spinal cord arteriography, which was performed in all five patients.

The findings support those of Kendall and Logue, that surgery restricted to elimination of the arteriovenous fistula at the intervertebral foramen is curative, and that more extensive surgery is unnecessary for this subgroup of AVM's of the spinal cord. These lesions comprise a sizable percent of all spinal AVM's. Resolution of myelopathy in these patients supports the hypothesis that venous hypertension causes chronic progressive myelopathy.
Carpal tunnel syndrome
Authors: Paine Kenneth W. E. , Polyzoidis Konstantinos S.
Published: May 2009

✓ The presenting symptomatology and clinical findings of 464 patients with the carpal tunnel syndrome are reviewed. The results of decompression by section of the transverse carpal ligament are presented, with particular reference to the use of the Paine retinaculotome. Approximately 90% of patients achieved very satisfactory results and complications were minimal. The commonest reason for failure is incomplete division of the flexor retinaculum. The detailed procedure is presented.
Intracranial meningiomas following low-dose irradiation to the head
Authors: Soffer Dov , Pittaluga Stefania , Feiner Michael , Beller Aaron J.
Published: May 2009

✓ Earlier reports have suggested that low-dose ionizing irradiation might be involved in induction of intracranial meningiomas. One of the problems in evaluating irradiation-induced neoplasms is the belief that these tumors have no distinguishing features to indicate their etiology. In an attempt to identify such features in meningiomas following irradiation, a group of 42 post-irradiation meningiomas (PIM's) has been compared with a group of 84 non-PIM control meningiomas. These 42 PIM's included all the intracranial meningiomas diagnosed at the Hadassah University Hospital during the years 1952 to 1981 in individuals treated in childhood with low-dose x-ray therapy for tinea capitis. Although the individual PIM does not seem to differ from a “spontaneous” meningioma, this study indicates that PIM's as a group have distinct characteristics, namely, their location at the site of maximal irradiation, and features suggesting rapid growth and aggressive biological behavior. There was a significantly higher number of calvarial tumors (p < 0.001), a high proportion of multiple meningiomas, a higher recurrence rate following apparent complete excision (p < 0.02), and an increased number of histologically malignant meningiomas (p < 0.01). The demonstration of features that distinguish PIM's from meningiomas of other etiology supports the suggestion that low-dose ionizing irradiation was involved in the pathogenesis of these tumors.
Intrasellar gangliocytoma and syndromes of pituitary hypersecretion
Authors: Fischer Edwin G. , Morris James H. , Kettyle William M.
Published: May 2009

✓ Syndromes of hypersecretion of pituitary hormone and sellar enlargement may on occasion be caused by a gangliocytoma instead of a pituitary adenoma. At least some of these rare tumors are apparently independent of and separable from the pituitary gland, its stalk, and the hypothalamus, and are therefore surgically removable without incurring further endocrine deficit. The authors report such a case, with successful removal of the tumor via a frontal craniotomy. The associated hypersecretion of pituitary hormone was corrected without disturbing normal pituitary function.
Epidermoid cyst occurring within a lumbosacral myelomeningocele
Authors: Martinez-Lage Juan F. , Masegosa José , Sola Joaquin , Poza Máximo
Published: May 2009

✓ The authors report the case of an infant who presented with an epidermoid tumor contained in a lumbosacral myelomeningocele. The association of spina bifida aperta and congenital intraspinal tumors is rare. Only two cases of teratoma and two cases of epidermoid tumors arising within a meningocele have been documented previously.
Ventricular taps in the neonate under ultrasonic guidance
Authors: Afschrift Marcel , Jeannin Philippe , de Praeter Claudine , van Egmond Harko , Voet Dirk
Published: May 2009

✓ A method of ultrasonically guiding ventricular taps in children is described. The needle is introduced through a needle guide in the ultrasound field of a sectorscanner. The direction of the needle is accurately determined and the needle itself is clearly visualized on the television monitor during its introduction into the brain. The results of seven punctures are presented. All these punctures were successful at the first attempt, and no complications occurred.