bluuebunny/crossref_metadata_2025 huggingface dataset:
Kaolin-induced congenital hydrocephalus in utero in fetal lambs and rhesus monkeys
Authors: Edwards Michael S. B. , Harrison Michael R. , Halks-Miller Meredith , Nakayama Don K. , Berger Mitchell S. , Glick Philip L. , Chinn Daryl H.
Published: May 2009

✓ A model of congenital hydrocephalus in utero in fetal lambs and rhesus monkeys has been produced by the intracisternal injection of kaolin. Initial attempts to produce hydrocephalus using silicone oil were unrewarding. Hydrocephalus had developed by 2 weeks post-injection and could be followed by ultrasonography. The pathological findings were similar to those reported using kaolin in other species. Ventriculoamniotic shunting, when successful, was capable of partially reversing the deleterious effects of hydrocephalus. The major drawback of the present model is that hydrocephalus is produced during the second rather than the first trimester of pregnancy. However, kaolin produces mainly an obstructive hydrocephalus without other associated brain or systemic anomalies.
Microsurgical anatomy of the recurrent artery of Heubner
Authors: Gomes Francisco , Dujovny Manuel , Umansky Felix , Ausman James I. , Diaz Fernando G. , Ray William J. , Mirchandani Haresh G.
Published: May 2009

✓ The recurrent arteries of Heubner were studied in 30 unfixed human brains (60 hemispheres) obtained from routine autopsies of individuals with a mean age of 34 years. The arteries were injected with tinted polyester resin via cannulation of the internal carotid arteries, and dissected under microscopic magnification. The recurrent artery of Heubner was absent in two hemispheres and double in seven hemispheres, either with a separate origin (in two) or from a common stem (in five). The artery of Heubner had a mean outer diameter of 0.8 ± 0.04 mm (range 0.3 to 1.5 mm) and a mean length of 23.4 ± 1.1 mm (range 12 to 38 mm). It originated from the A2 segment of the anterior cerebral artery (ACA) in 57% of the specimens, from the junction of the ACA and the anterior communicating artery in 35%, and from the A1 segment of the ACA in 8%.

Three types of recurrent courses were observed. In the Type I or superior course, seen in 41 (63%) of the 65 arteries, the artery followed the superior wall of the A1 segment of the ACA. In the Type II or anterior course, the arteries found in 22 (34%) of specimens maintained a rostral position in relation to the A1 segment. In the Type III or posterior course, taken by two (3%) arteries, a posterior course of the vessel in the anterior perforated substance was found. The branching pattern was identified down to a range of 100 to 200 µ, and the average number of branches was 6.5 ± 0.4 (range 3 to 12). Four groups of branches were observed. The olfactory group was represented in 91% by a single olfactory branch, with a mean outer diameter of 0.3 ± 0.03 mm. On average, 1.9 ± 0.27 frontal branches were found with a mean diameter of 0.13 ± 0.01 mm. The branches penetrating the anterior perforated substance had a larger outer diameter (mean 0.4 ± 0.03 mm) with an average number of 2.5 ± 0.2 branches. The Sylvian fissure branches were more numerous (mean 3 ± 0.3) with a mean outer diameter of 0.4 ± 0.03 mm. The point of penetration of the main trunk was found to be constant at the level of the lateral perforated substance-medial Sylvian fissure in 85% of the cases.

This report emphasizes the advantages of the intravascular casting resin injection technique in unfixed human brains over other conventional methods. It also describes the application of these anatomic data to the surgical strategy for the anterior circle of Willis, including the possible use of the recurrent artery of Heubner for microvascular reconstructive procedures.
Aminergic innervation of cerebral veins
Authors: Itakura Toru , Nakakita Kazuo , Kamei Ichiro , Naka Yutaka , Nakai Kunio , Komai Norihiko , Yokoi Hideki , Nishimura Osamu , Okada Naniwa
Published: May 2009

✓ The density and distribution pattern of aminergic nerve fibers in intracranial and extracranial veins were compared by means of catecholamine histofluorescence studies. Extracranial veins (internal jugular, inferior caval, portal, renal, internal iliac, and femoral veins) showed quite a uniform distribution pattern. Large veins (jugular, caval, renal, and iliac veins) revealed a spiral pattern, and small veins presented as a meshwork (femoral vein) or in a longitudinal pattern (a branch of the femoral vein). In contrast, intracranial veins displayed more complex patterns: the dural sinus showed a longitudinal pattern and the internal cerebral vein and the superficial vein of Labbé revealed a meshwork of nerve fibers. The aminergic fibers were denser in cerebral veins (dural sinus and internal cerebral vein) than in extracranial veins. The complex distribution and the density of aminergic fibers in cerebral veins suggest that the aminergic innervation of the circulatory system may be more important in the brain than in the extracranial organs.
Carotid to distal vertebral artery bypass for vertebrobasilar ischemia
Authors: Camp Perry E.
Published: May 2009

✓ A simple technique is described for a venous graft between the common carotid artery and the extracranial vertebral artery. In the case described, the vertebral artery was shown angiographically to be occluded and reconstituted by collateral vessels. This patient had symptoms of vertebrobasilar insufficiency which resolved postoperatively.
Tuberculous meningitis presenting as an obstructive myelopathy
Authors: Vlcek Brien , Burchiel Kim J. , Gordon Thomas
Published: May 2009

✓ Subacute paraplegia progressing over 3 months due to spinal cord compression was the presenting symptom of tuberculous meningitis in this patient with a normal chest x-ray film and no radiological or autopsy evidence of Pott's vertebral tuberculosis. The obstructive myelopathy was the result of proliferative granulomatous meningitis. A review of the literature indicates that this is a very unusual presentation of tuberculous meningitis.
Transparent optical neurosurgical instruments
Authors: Levy Walter J.
Published: May 2009

✓ Neurosurgical instrumentation over the last two decades has improved with the increasing use of the operating microscope and has provided much better visualization and lighting of the surgical field. During this time, dissecting instruments have become smaller, but they sacrifice some of the microscopic gains because they are made of opaque metal. This has the disadvantage of hiding from the surgeon the area of the surgical field being worked on. This paper reports the development of transparent instruments that are strong enough to be used in dissection and yet do not sacrifice part of the improved visualization and lighting gained with the operating microscope. Made of a high-strength plastic, these instruments can be used for dissection in surgical procedures and allow the surgeon to look through them and observe the tissues underneath. He can watch the condition of blood vessels and nervous tissues with an improved visibility that can help to avoid damage to delicate structures. Furthermore, as hidden structures such as small vessels come into view they are identified earlier. These instruments can also incorporate jeweled cutting edges and use their optical properties to improve further visualization of the surgical field.
Nutrition and the neurosurgical patient
Authors: Gadisseux Philippe , Ward John D. , Young Harold F. , Becker Donald P.
Published: May 2009

✓ There has been a rapid expansion of knowledge in the field of nutrition and metabolism with regard to the general surgical patient. However, only recently has there been greater appreciation of the benefits of adequate nutrition and appropriate metabolic care of the neurosurgical patient. In this review, the authors attempt to outline 1) the metabolic response to stress in general, and how it applies to the neurosurgical patient; 2) how best to provide adequate nutritional support for the neurosurgical patient; 3) the effects of nutrition on neurotransmitters; and 4) the effect of diet and nutrition on patients with malignant brain tumors.
Perioperative use of somatosensory evoked responses in aneurysm surgery
Authors: Symon Lindsay , Wang Alexander D. , Costa e Silva Izabel E. , Gentili Fred
Published: May 2009

✓ Somatosensory evoked potentials have been recorded during 34 operations for intracranial aneurysm. The central conduction time (CCT), the time between the N14 peak (recorded at C-2) and the N20 peak (recorded at the cortex) in response to median nerve stimulation, has been found to be increased by administration of halothane, by brain retraction, and by temporary vascular occlusion in some instances. Increase of CCT to more than 10 msec, or disappearance of the response was associated in two cases with postoperative neurological deficit, neither permanent. In a further case, prolongation of CCT was used as a guide to the repositioning of an imperfectly placed clip on a middle cerebral artery aneurysm. The value of the technique as a perioperative monitoring system is discussed.
The use of greater omentum vascularized free flaps for neurosurgical disorders requiring reconstruction
Authors: Barrow Daniel L. , Nahai Foad , Tindall George T.
Published: May 2009

✓ The heterotopic transfer of composite tissue, with microvascular anastomosis of an arterial supply and venous drainage to locally existing vessels, has received considerable attention in the plastic surgical literature. The use of latissimus dorsi musculocutaneous free flaps has been reported in the repair of large defects of the scalp, cranium, and dura following resection of invasive neoplasms or trauma. When the defect involves primarily subcutaneous tissue loss resulting in abnormal contour, omental free flaps provide effective coverage and restoration of contour. In addition, the inherent capability of the omentum to combat infection and form an ideal bed for the establishment of skin or bone grafts provides further indications for its use.

The authors have used omental free flaps in nine cases to reconstruct gunshot wounds of the head, orbit, and face, heal chronic cavitating frontal sinus infections, form a base over exposed dura for reconstruction of the skull with rib grafts, and cover large defects after resection of invasive tumors or infected scalp. These wounds of neurosurgical interest were reconstructed with acceptable structural and aesthetic results. The indications, surgical techniques, results, alternative procedures, and potential complications of this procedure are discussed. The authors believe that omental free flaps should be considered an option in the armamentarium of reconstructive approaches for skull, dural, scalp, orbital, and facial wounds.
Origin and evolution of plateau waves
Authors: Rosner Michael J. , Becker Donald P.
Published: May 2009

✓ Laboratory observations made in cats with fluid-percussion head injuries have suggested that plateau waves or Lundberg “A-waves” are not independent of systemic circulatory events. Four distinct phases in the evolution of the plateau wave have been identified, and each related to a circulatory change in a causal manner. The first phase is the premonitory drift phase where intracranial pressure (ICP) gradually increases prior to the plateau proper. This phase is caused by a slow gradual decline in systemic arterial blood pressure (SABP) which increases ICP by autoregulatory vasodilation and reduces cerebral perfusion pressure (CPP) to a range of 70 to 80 mm Hg. The second phase is the plateau phase initiated at a CPP of about 70 to 80 mm Hg, and is characterized by a rapid increase in ICP as CPP falls further to 40 to 50 mm Hg. The plateau lasts as long as the CPP remains stable and above ischemic levels. The third phase is the ischemic response, characterized by CPP being returned toward normal by increases in SABP in response to very low CPP's. The fourth phase is the resolution, characterized by a rapid decline in the ICP to baseline levels with stabilization of the SABP and CPP, and is best explained by autoregulatory vasoconstriction.

Plateau waves appear to occur as the result of intact or mostly intact autoregulation responding to changes in CPP. The series of events that follow are best explained by what is known of normal autoregulation; the various properties of plateau waves are viewed and explained as the expected and logical consequences of an unstable CPP acting upon a generally intact cerebrovascular bed in the face of elevated ICP and decreased compliance.
Significance of contrast enhancement in cranial computerized tomography after subarachnoid hemorrhage
Authors: Doczi Thomas , Ambrose James , O'Laoire Sean
Published: May 2009

✓ Eighty patients with subarachnoid hemorrhage underwent computerized tomography (CT) scanning before and after administration of Conray contrast medium. Abnormal enhancement was seen in visual evaluation of the CT scans in 26 cases, in the regions bordering the subarachnoid spaces. Abnormal enhancement was associated with a poor clinical condition, angiographic spasm, and a poor outcome. Measurements of absorption values in the thalamus revealed significant increases in density after contrast enhancement in those patients whose scans showed abnormal enhancement in the regions bordering the subarachnoid spaces on visual evaluation. The authors suggest that the abnormal enhancement is parenchymal, in the gyri, and is not “subarachnoid.” They suggest that it is due to gyral hyperemia or extravasation of contrast material into the cortex resulting from breakdown of the blood-brain barrier, or a combination of both factors.
Posthemorrhagic hydrocephalus
Authors: Ment Laura R. , Duncan Charles C. , Scott David T. , Ehrenkranz Richard A.
Published: May 2009

✓ In addition to seizures and long-term neurodevelopmental handicaps, infants with intraventricular hemorrhage (IVH) are at risk for posthemorrhagic hydrocephalus (PHH), and the incidence of this problem in preterm infants with known IVH has been reported to vary from 25% to 74%. Over a 46-month period, 438 neonates of 1250-gm birth weight or less were admitted to this Newborn Special Care Unit, and 269 survived the first 36 postnatal hours. Of these, 265 patients underwent computerized tomography and/or cranial ultrasound scanning for evaluation of germinal matrix and/or intraventricular hemorrhage (GMH/IVH): 133 infants were found to have experienced GMH/IVH, and 27 of these died within the 1st postnatal week. Of the 95 survivors with GMH/IVH, 43 were known to have GMH only; the other 52 experienced IVH and were therefore at risk for PHH. Patients with GMH/IVH underwent repeat investigations for the development of ventriculomegaly and possible PHH. Only five patients with IVH developed PHH, defined as ventriculomegaly, elevated intracranial pressure, and increasing occipitofrontal head circumference. Serial cranial ultrasound studies of 95 other consecutively admitted patients in this birth-weight range revealed an equal incidence (45%) of low intracranial pressure ventriculomegaly in both the hemorrhage and non-hemorrhage groups, but none of them required shunting for hydrocephalus. One infant with congenital aqueductal stenosis was also identified.
Diagnosis of an “isodense” pituitary microadenoma by dynamic CT scanning
Authors: Hasegawa Takeshi , Ito Haruhide , Shoin Katsuo , Kogure Yuzaburo , Kubota Toshihiko , Yamamoto Shinjiro
Published: May 2009

✓ A case of Nelson's syndrome with an adrenocorticotropic hormone-secreting pituitary chromophobe microadenoma is presented to demonstrate the potential capability of rapid sequential (dynamic) computerized tomography (CT) scanning for the diagnosis of a pituitary microadenoma that was isodense with the adjacent pituitary gland on conventional enhanced CT scanning. The dynamic CT scans showed transient high density in this microadenoma contrasting with the pituitary gland in the early-enhancement phase, and thereafter the contrast density was indistinguishable from that of the pituitary gland in the delayed-enhancement phase. For the detection of pituitary microadenoma, dynamic CT combined with subsequent delayed CT scanning can provide diagnostic and localizing information.
Spinal cord monitoring during surgery by direct recording of somatosensory evoked potentials
Authors: Whittle Ian R. , Johnston Ian H. , Besser Michael
Published: May 2009

✓ A simple method of spinal cord monitoring that can be readily used during surgery for spinal disorders in children or adults is described. A spinal subdural recording electrode is placed rostral to the site of surgery and the peroneal nerve is stimulated in the popliteal fossa; in this way, large-amplitude polyphasic spinal somatosensory evoked potentials (SEP's) can be directly recorded. The large amplitude of the spinal SEP's recorded intrathecally facilitates spinal cord monitoring by allowing: 1) rapid acquisition of the evoked response, which provides continuous monitoring during surgery; 2) relatively easy interpretation of the signal, there being no significant ultrashort- or long-latency components to the waveform; and 3) signal acquisition in an electrical environment that would be unacceptable using standard methods of spinal and cortical SEP recording.
Effect of phenytoin and corticosteroids on seizures and lipid peroxidation in experimental posttraumatic epilepsy
Authors: Willmore L. James , Triggs William J.
Published: May 2009

✓ Head trauma, intracerebral hematoma formation, and hemorrhagic cerebral infarction cause extravasation of the intravascular contents, red blood cell (RBC) hemolysis, hemosiderin deposition within the neuropil, and an increased incidence of epilepsy. Reports conflict regarding the efficacy of the administration of prophylactic anticonvulsant drugs to head-injured patients to prevent the development of posttraumatic epilepsy. In this study, rats received a 10-µl injection of 100 mM FeCl2 at a depth of 1.8 mm into the isocortex, or an equal volume of saline. Rats were then treated with 30 mg/kg methylprednisolone (MPS), 90 mg/kg MPS, 100 mg/kg phenytoin, or with an equal volume of propylene glycol. Behavioral or electroencephalographic (EEG) seizures occurred in all control-treated iron-injected rats within 93 ± 6 minutes of injection. Brain injury responses as measured by the occurrence of fluorescent product formation from iron-induced lipid peroxidation showed 6.6 ± 0.8 units/gm in the saline-injected animals, and 16.7 ± 2.5 units/gm in the control-treated iron-injected rats. Of the 90-mg/kg MPS-treated rats, 8% had seizures; fluorescence in those animals was 5.7 ± 0.5 units/gm. Phenytoin treatment prevented the occurrence of convulsive and EEG seizures; however, lipid peroxidation was unaffected (16.5 ± 4.1 units/gm).

If posttraumatic epilepsy develops because of RBC extravasation, hemolysis, parenchymal deposition of heme compounds, and initiation of lipid peroxidation, then treatments designed to prevent peroxidation may be more effective for epilepsy prophylaxis than administration of anticonvulsant drugs that mask convulsive seizures while biochemical brain injury continues.
Acute responses to experimental blunt head trauma
Authors: Tornheim Patricia A. , Prioleau George R. , McLaurin Robert L.
Published: May 2009

✓ Anesthetized cats subjected to impact followed by acceleration and rotation of the skull were sacrificed at 15 minutes or 6 hours after injury and were selected for study if unilateral cerebral contusion was present. Widespread areas of cerebral cortex were examined bilaterally for edema, using measurement of tissue density with an organic gradient, and for breakdown of the blood-brain barrier to plasma protein tagged with Evans blue dye. At both times tested, a halo of vasogenic edema (Evans blue stain plus decreased density) was present in the cortex surrounding areas of contusion. At 15 minutes after injury, animals with deep contusions also had a slight decrease in density without Evans blue staining, interpreted as cytotoxic edema, in some gyri neighboring the contusion. At 6 hours, cytotoxic edema was not evident, but some animals had vasogenic edema in the gyri adjoining the contusion. Most gyri contralateral to contused areas had neither Evans blue staining nor changes in tissue density. These findings suggest that, with the present head-injury model, acute changes in tissue density and vascular permeability occur in the cerebral cortex of hemispheres with contusion. These responses are related topographically to contusion sites, and change over the two times studied. The authors conclude that events in addition to spread of fluid from areas of contusion contribute to the edema of head injury, and that more than one form of edema can follow mechanical trauma to the brain.
Alteration of somatosensory evoked potentials in response to global ischemia
Authors: Lesnick James E. , Michele John J. , Simeone Frederick A. , DeFeo Steven , Welsh Frank A.
Published: May 2009

✓ The somatosensory evoked potential (SEP) measured in response to median nerve stimulation was correlated with cortical and white matter cerebral blood flow (CBF), adenosine triphosphate (ATP), and lactate levels in 14 cats subjected to graded hemorrhagic hypotension following bilateral carotid artery ligation. Three additional cats served as controls. Regional CBF was determined by the hydrogen clearance method, and the time for conduction of the sensory stimulus from the thalamus to the cortex (the thalamocortical conduction time), was used to assess SEP latency changes. A reproducible sequence of changes occurred in the SEP as ischemia developed. There was an early conduction delay that correlated well with mild white matter ischemia. Amplitude reductions in the SEP began as significant cortical ischemia occurred. The cortical SEP was abolished when white matter CBF and ATP fell to critical levels.
Cerebellopontine angle meningiomas
Authors: Sekhar Laligam N. , Jannetta Peter J.
Published: May 2009

✓ During the years 1974 through 1981, 22 patients with cerebellopontine angle meningiomas underwent surgery: 14 tumors were excised completely, and eight subtotally. A retromastoid approach was used in 19 cases and a subtemporal approach in three cases. There was no operative mortality and the quality of survival was good. Five patients suffered new cranial nerve deficits as a result of the operation. The average follow-up period was 5 years. One tumor thought to be completely removed has recurred, but has not required another operation so far. One subtotally excised tumor required reoperation. Computerized tomography and arteriography were important in preoperative evaluation. Good neuroanesthesia, the use of the surgical microscope and microtechnique, and an understanding of the pathological relationships were factors contributing to good results.
The Nd:YAG laser in neurosurgery
Authors: Wharen Robert E. , Anderson Robert E. , Sundt Thoralf M.
Published: May 2009

✓ The Nd:YAG laser has been used safely to aid in the resection of 10 cases of parenchymal arteriovenous malformations (AVM's). The laser was, found helpful for: 1) defining the plane between the AVM and the brain; 2) coagulating any dural component of the AVM; and 3) achieving hemostasis of the bed following resection of the lesion. However, its overall benefit in the resection of AVM's remains to be determined, as it could not arrest active high-flow bleeding from the thin-walled vessels feeding the deep portion of the AVM. This was attributed to the inherent characteristics of these vessels, since the instrument has been effective in non-AVM arteries of similar dimensions containing contractile elements in the vessel walls. Future refinements in focusing instrumentation and operative technique should enhance its capabilities and usefulness. When used within the recommended power range, the Nd:YAG laser is safe and its penetration predictable. The fiberoptic cable light delivery system allows excellent mobility of the handpiece, but the protective eyewear laser-light filters reduce the available light to the surgeon. The instrument appears promising but more work is required.
Comparison of sodium thiopental and methohexital for high-dose barbiturate anesthesia
Authors: Boarini David J. , Kassell Neal F. , Coester Hans C.
Published: May 2009

✓ High-dose sodium thiopental is frequently used in neuroanesthesia. The authors performed a study to compare a shorter-acting barbiturate, methohexital, to sodium thiopental in producing high-dose barbiturate anesthesia. In two groups of five mongrel dogs each, regional cerebral blood flow (CBF) was determined using the radioactive-microsphere technique, and cardiovascular parameters were measured before, during, and 1 hour after a 1½hour period of deep barbiturate anesthesia with either sodium thiopental or methohexital. Doses of the barbiturates were adjusted to produce electroencephalogram burst suppression of greater than 30 seconds.

Both agents produced a similar degree of cardiac depression, reduction in CBF, and decrease in cerebral metabolic rate of oxygen (CMRO2). Changes in cerebral and peripheral vascular resistance indicated that methohexital caused less vasoconstriction than sodium thiopental. When the barbiturate infusions were discontinued, CMRO2 and CBF returned more rapidly toward control values in the methohexital group than in the thiopental group. The more rapid recovery time and decrease in cerebral vascular resistance with methohexital suggest that it may have some advantage over sodium thiopental during certain neurosurgical procedures.
Multiple intracranial metastases of malignant melanoma with long-term survival
Authors: Fernandez Eduardo , Maira Giulio , Puca Alfredo , Vignati Andrea
Published: May 2009

✓ The authors present a case of multiple brain metastases and an extracranial secondary localization from malignant melanoma. The patient was operated on three times for the intracranial masses and had a 49-month survival with a good quality of life after the first of the three operations. She lived a total of 80 months from the time of diffusion of the primary tumor. The course of malignant melanoma is unpredictable, and long-term survival can be achieved in some cases, even in the presence of multiple brain metastases.
Pulsating unilateral exophthalmos due to traumatic aneurysm of the intraorbital ophthalmic artery
Authors: Rahmat Hamid , Abbassioun Kazem , Amirjamshidi Abbass
Published: May 2009

✓ A case of pulsating unilateral exophthalmos is presented. It was caused by a traumatic aneurysm of the intraorbital ophthalmic artery, secondary to missile injury. Evolution of the aneurysm was observed clinically, by angiography, and by computerized tomography. The differential diagnosis of pulsating exophthalmos and the pathogenesis of such aneurysms are briefly discussed.
Telemetric ICP monitoring after surgery for posterior fossa and third ventricular tumors
Authors: Chapman Paul H. , Cosman Eric , Arnold Michael
Published: May 2009

✓ After surgery for posterior fossa or third ventricular tumors, hydrocephalus may persist or evolve. Proper management of this complication requires timely detection. Temporary external ventricular drainage has been suggested by some authors as an adjunct to clinical observations and radiographic studies for unshunted patients. As an alternative, the authors have used a telemetric method of pressure monitoring in association with a ventricular catheter and subcutaneous reservoir. This has been found useful in eight patients without the disadvantages inherent in other methods of management.
Some inquiries in neuroanesthesia and neurological supportive care
Authors: Frost Elizabeth A. M.
Published: May 2009

✓ Complications of performing neurosurgery in the sitting position have been well defined, and include cardiac and respiratory effects, air embolism, and pneumocephalus. Prophylactic measures and early diagnosis allow prompt therapy with minimal residual sequelae. All anesthetic agents and techniques alter the intracranial dynamics. A clear understanding of drug effects and the pathology involved allow a rational choice of anesthetic management to maximize the potential for a good outcome. Patients with cerebrovascular disorders frequently have multisystem disease, and careful preanesthetic assessment and preparation ensure a more stable intraoperative and postoperative course. Many chemical and mechanical reactions follow an ischemic hypoxic insult, but appropriate therapeutic intervention and early establishment of cardiorespiratory support measures have shown promise in improving the neurological outcome in these patients.
The contribution of brain injury to the overall injury severity of brain-injured patients
Authors: Fife Daniel , Jagger Janine
Published: May 2009

✓ Several recent population-based studies of the incidence of head injury have identified cases by screening hospitalized patients. This method assumes a close relationship between severity of head injury and overall injury severity, since it is the latter that determines hospital admission. Thus, a patient whose overall injury severity is high will be admitted to the hospital regardless of the degree of his head injury. Similarly, since a patient's outcome status after treatment depends on his response to all his injuries, studies of the prognosis of various types of head injury also assume a close relationship between head injury severity and overall injury severity.

The present study examines the relationship between brain injury severity and overall injury severity in a series of hospitalized head-injured patients with evidence of actual or probable brain trauma. Among these patients, brain injury severity was closely related to overall injury severity. Head injury severity and head and neck injury severity were also closely related to overall injury severity. For all other body regions, injury severity was not closely related to overall injury severity in this group of patients.
Intraoperative ultrasonic evaluation of spinal cord motion
Authors: Jokich Peter M. , Rubin Jonathan M. , Dohrmann George J.
Published: May 2009

✓ The spinal canals of 11 patients with various pathological conditions, both benign and malignant, were examined intraoperatively using real-time ultrasonography. The spinal cords in eight of these patients with lesions causing cord compression were seen to oscillate rhythmically over each mass with a frequency corresponding to the patient's arterial pulsations. The majority of the observed motion was transmitted or extrinsically induced from compression of the anterior spinal artery. In one case, after resection of an anterior cervical neurofibroma, these oscillations diminished markedly. Spinal cord motion, as described, has important implications for neurosurgery, since it contradicts the previously held belief that oscillations of the spinal cord or dura mater imply a “free” or noncompressed spinal cord. Furthermore, spinal cord motion may play a role in the degradation of computerized tomography images of the cord, since these movements are maximized at the areas with the most severe pathology.
Megadose corticosteroid therapy following experimental traumatic spinal injury
Authors: Faden Alan I. , Jacobs Thomas P. , Patrick Darryl H. , Smith Michael T.
Published: May 2009

✓ Corticosteroids are frequently used in the treatment of spinal trauma, although neither experimental nor clinical evidence to support their use is persuasive. Recently there have been claims that extremely high doses (“megadoses”) of corticosteroids (equivalent to 15 to 30 mg/kg of methylprednisolone) improve neurological recovery compared to results with traditional steroid doses. The authors have compared the effect of megadose dexamethasone and methylprednisolone therapy to that of saline treatment following traumatic cervical spinal injury in the cat. During 6 weeks postinjury, neurological recovery did not differ significantly in corticosteroidtreated and saline-treated animals. Moreover, histopathological changes in the spinal cord were similar in methylprednisolone- and saline-treated cats. Corticosteroid-treated animals had a higher mortality rate than did control animals, with the predominant cause of death being neurogenic pulmonary edema. It is concluded that megadose corticosteroid treatment does not improve neurological recovery in this experimental model of spinal injury, and is associated with increased mortality.
Antibiotic prophylaxis in neurosurgery
Authors: Geraghty James , Feely Micheal
Published: May 2009

✓ A randomized trial was performed to support the contention that prophylactic antibiotics can reduce the incidence of postoperative neurosurgical wound infections. The regime outlined by Malis was followed. Vancomycin and gentamicin were administered systemically just prior to surgery and streptomycin was added to the irrigating solution. Patients were randomly assigned to two groups: control and treated. The infection rate in the control group was 3.5% and in the treated group 0.5%.
Intracranial venous sinus hypertension: cause or consequence of hydrocephalus in infants?
Authors: Sainte-Rose Christian , LaCombe Jacques , Pierre-Kahn Alain , Renier Dominique , Hirsch Jean-François
Published: May 2009

✓ From a previous study of achondroplasia as well as from the observation of patients with hydrocephalus associated with craniostenosis, the authors have concluded that an increased superior sagittal sinus venous pressure (SSVP) could be the cause of the enlarged ventricles. However, other workers have demonstrated that an increased SSVP could be the consequence of increased intracranial pressure (ICP). Therefore, the authors undertook a study to determine if there was a physiological test that could distinguish between rare instances of increased SSVP caused by structural and irreversible narrowing of the sinus and those caused by increased ICP.

In 20 hydrocephalic infants and children, pressure was simultaneously measured in the lateral ventricle, the superior sagittal sinus, and the jugular vein. Stable baseline pressures were recorded, as well as the variations observed after the withdrawal of an amount of cerebrospinal fluid (CSF) sufficient to lower ICP to zero. Similar recordings were taken after reinjection of an equal quantity of CSF. In all of the patients, SSVP was increased, but not as much as the ICP. In the cases of hydrocephalus without any associated cranial malformation, and therefore without any likely anatomical interruption of the sinus, CSF withdrawal induced a simultaneous decrease of ICP and SSVP. However, whereas ICP could be lowered to zero, SSVP never fell below the jugular venous pressure, which remained stable (around 5 mm Hg) throughout the recording session. Results were different when sinography demonstrated an anatomical interruption of the sinus, as in cases of hydrocephalus associated with achondroplasia or craniostenosis. In these cases, although ICP was normally lowered by CSF withdrawal, SSVP remained nearly unchanged, usually greater than the jugular venous pressure.

The present study demonstrated that SSVP recording during ICP variations induced by CSF withdrawal permits differentiation between a reversible collapse of the sigmoid sinus due to increased ICP and a fixed obstructive lesion of the sinuses. Based upon this test and the results of sinography, the authors inserted a venous bypass between the lateral sinus and a jugular vein in three patients.
Booster clips for giant and thick-based aneurysms
Authors: Sundt Thoralf M. , Piepgras David G. , Marsh W. Richard
Published: May 2009

✓ The authors describe their experience using booster clips to secure the closure of primary clips in the repair of giant and other thick-walled aneurysms. These clips were used for 21 aneurysms in 20 patients, comprising 12% of all aneurysms operated on during the 15-month period of the report, but representing about 50% of all giant aneurysms operated on during the same time frame. These clips are designed to encircle the primary clip and have fixation “shoes” to close upon the jaws of the primary clip. All aneurysms were opened for decompression and thrombectomy when necessary following temporary major vessel occlusion before placement of the primary clip. Cerebral blood flow measurements and continuous electroencephalographic monitoring were utilized to predict the brain's tolerance to temporary ligation of the internal carotid artery (ICA) in those cases with a giant aneurysm arising from that vessel. There were no complications attributable to the periods of intracranial or cervical ICA occlusion; these periods varied but did not exceed 8 minutes for the former nor the tolerance period for the latter, which was calculated as from 5 to 30 minutes. It was necessary to reoperate on two patients and reposition clips because of stenoses or occlusions identified on immediate postoperative angiography. Fifteen patients had normal neurological function at the time of discharge. Three patients had minor deficits which did not prevent employment; two of these were related to a preoperative deficit and one was a complication of delayed ischemia. There were two deaths: one from bleeding complications and probable damage to perforating vessels in a patient operated on under profound hypothermia (the only case in the series so managed), and one from respiratory complications in a patient with severe pulmonary problems.
Changes in intracranial stenotic lesions after extracranial-intracranial bypass surgery
Authors: Awad Issam , Furlan Anthony J. , Little John R.
Published: May 2009

✓ The natural history of intracranial arterial stenosis is not well understood. The lesions are pathologically quite diverse, and are subject to resolution, progression, or occlusion. The authors undertook an investigation to examine what effects, if any, extracranial-intracranial (EC-IC) bypass surgery had on the evolution of intracranial arterial stenosis in 18 patients undergoing EC-IC bypass procedures for ipsilateral hemispheric ischemia. There was inaccessible internal carotid artery stenosis in 14 patients, and middle cerebral artery stenosis in four patients. Early (within 2 weeks) and late (at 6 months) postoperative angiography was performed in all patients. During the period of the study, there was a significant change in the arterial stenosis in 50% of the patients (nine of 18). The stenotic artery became occluded in four patients while the grafts were widely patent. The occlusion occurred within a few days after the operation in three of the four cases, and was accompanied by an ischemic stroke in these patients. There was improvement or resolution of the stenotic lesion in five patients; the graft became occluded in two of these cases and was patent but showed poor cortical artery filling in the other three. All these patients remained asymptomatic and the change was detected on routine late postoperative angiograms. It is concluded that arterial stenoses should not be viewed as static or inflexible lesions, and that EC-IC bypass procedures can modify the hemodynamic parameters across stenotic lesions, predisposing them to improvement or worsening. This, in turn, may affect bypass patency. Such hemodynamic interactions are accompanied by ischemic symptoms in some patients, and contribute to the relatively higher morbidity associated with EC-IC bypass surgery in the setting of arterial stenosis.
Does the CO2 laser spread viable brain-tumor cells outside the surgical field?
Authors: Voorhies Rand M. , Lavyne Michael H. , Strait Timothy A. , Shapiro William R.
Published: May 2009

✓ The viability of debris containing C6 rat tumor cells generated by the CO2 laser was investigated using standard tissue culture techniques. No evidence of cell viability was found in the plume of laser smoke.
Observations on synkinesis in patients with hemifacial spasm
Authors: Kim Phyo , Fukushima Takanori
Published: May 2009

✓ In 95 patients with hemifacial spasm, synkinetic actions were measured objectively using electromyographic examination of the blink reflex and impedance audiometry. Abnormal synkinesis between the orbicularis oculi and the orbicularis oris muscles was recorded in 93% of cases, while synkinesis between the stapedius muscle and the facial muscles was recorded in 87%. Neither of these effects could be demonstrated on the unaffected side. The examinations were performed before and after microvascular decompression in 66 cases. Rapid disappearance of synkinesis, often within 10 days, was observed after the relief of vascular compression in 81% of patients who had not undergone previous peripheral facial nerve block procedures. These findings indicate that the synkinesis seen in hemifacial spasm is essentially a reversible condition, and suggest that axonal ephaptic conduction at the vascular compression site plays an important role in the pathophysiological mechanism of hemifacial spasm.
Dysplastic gangliocytoma of cerebellum in a newborn
Authors: Roessmann Uros , Wongmongkolrit Thamnook
Published: May 2009

✓ Dysplastic gangliocytoma of the cerebellum is reported in a newborn. It is characterized by large ganglion cells in the molecular layer and premature attenuation of the external granule-cell layer. The internal granule-cell layer appears rarefied but otherwise normally organized. It appears that in this disease the migrating granule cells mature too early and become arrested in the molecular layer, because of their abnormal forms, while others continue to migrate and grow in size in their normal location in the inner granule-cell layer.
Familial oligodendroglioma
Authors: Roosen Norbert , De La Porte Christian , Van Vyve Michel , Solheid Claude , Selosse Paul
Published: May 2009

✓ A case of familial oligodendroglioma, occurring in a mother and her daughter, is presented.
Intraradicular herniated lumbar disc
Authors: Barberá José , Gonzalez-Darder José , García-Vazquez Fernando
Published: May 2009

✓ An unusual case is presented in which a fragment of herniated lumbar disc was found within the sheath of the S-1 nerve root. The possible pathogenic factors are discussed.
Indwelling double-balloon shunt for carotid endarterectomy
Authors: Furui Tomoo , Hasuo Michiaki
Published: May 2009

✓ The authors describe an indwelling intraluminal shunt for carotid endarterectomy. The device is equipped with balloons at both ends to prevent bleeding and to hold the tube in place. The design permits use of a small tube which facilitates insertion, and prevents intimal damage and limitation of exposure of arterial plaque.
CSF smooth-muscle constrictor activity associated with cerebral vasospasm and mortality in SAH patients
Authors: Kaye Andrew H. , Tagari Philip C. , Teddy Peter J. , Adams Christopher B. T. , Blaso William P. , Boullin David J.
Published: May 2009

✓ Cerebrospinal fluid (CSF) was collected preoperatively (by lumbar puncture) or perioperatively (by lumbar or ventricular drain) from 32 patients with subarachnoid hemorrhage (SAH) from ruptured intracranial aneurysms. Samples were also obtained from six control patients without evidence of subarachnoid blood. Smooth-muscle constrictor activity in the CSF was measured by bioassay using the isolated rat stomach fundus preparation. Concentrations of unidentified smooth-muscle constrictor substances were considerably greater in CSF from a group of seven patients with evidence of severe angiographic vasospasm and/or delayed ischemic deficits who died (73.8 ± 39.7 nmol/liter prostaglandin E2 (PGE2) equivalents), as compared to 25 other SAH patients who survived (6.5 ± 1.4 nmol/liter PGE2 equivalents), and six control patients (1.17 ± 0.34 nmol/liter PGE2 equivalents). The data suggest that there is a relationship between smooth-muscle constrictor substances in the CSF after SAH and both the degree of angiographic vasospasm and the outcome. It is possible that this relationship might be exploited clinically.
Causes of acute deterioration in patients with a ruptured intracranial aneurysm
Authors: Vermeulen Marinus , van Gijn Jan , Hijdra Albert , van Crevel Hans
Published: May 2009

✓ The authors studied the acute neurological deterioration in 150 patients with aneurysmal hemorrhage. These patients were closely observed for a 4-week period or until death or operation. Forty-six patients suffered a total of 62 episodes of deterioration that developed within 5 minutes after aneurysm rupture; 59 of these episodes consisted of severe impairment of consciousness. Computerized tomography (CT) was performed within a few hours of the event. Serial scans were obtained at least weekly after admission. Rebleeding was diagnosed as the cause of 42 episodes (68%), including six patients who died rapidly without a repeat CT scan. The final diagnosis of the cause in other acute episodes was epilepsy (in six), acute onset of ischemia (in three), and ventricular fibrillation (in one). Ten unexplained events occurred in nine patients. Rebleeding could be excluded with confidence in nine of these events, because the residual clots had disappeared or markedly decreased on CT. It is concluded that a purely clinical diagnosis of rebleeding will be incorrect in about every third patient, even if these patients are under close observation.
CSF dynamics in patients with subarachnoid and/or intraventricular hemorrhage
Authors: Kosteljanetz Michael
Published: May 2009

✓ The purpose of this study was to examine the extent to which reduction of cerebrospinal fluid (CSF) absorption contributes to raised intracranial pressure (ICP) in patients with acute subarachnoid hemorrhage (SAH). Seventeen patients suffering from SAH and/or intraventricular hemorrhage were studied; all were admitted in Grades II to V according to Hunt and Hess. Eleven patients had a proven aneurysm. The ICP, monitored via an intraventricular catheter, was above 15 mm Hg (2 kPa) during part of the monitoring period in all patients. B-waves at 1/min were noted in all patients. Resistance to outflow of CSF was determined by the following techniques: 1) bolus injection; 2) constant-rate steady-state infusion; or 3) controlled withdrawal (“inverse infusion”). Resistance to outflow of CSF was increased in all patients, ranging from 11.5 to 85 mm Hg/ml/min. The ICP was linearly correlated with outflow resistance. Four (50%) of the eight survivors required a shunt. Neither the presence of hydrocephalus on admission, nor the level of ICP, nor the magnitude of resistance to outflow of CSF was clearly related to the requirement of a permanent CSF diversion.
The correlation between surgical and CT estimates of brain damage following missile wounds
Authors: Carey Michael E. , Tutton Roger H. , Strub Richard L. , Black F. William , Tobey Emily A.
Published: May 2009

✓ The occurrence of distant brain damage following an apparent focal missile injury to the brain has not been well documented until computerized tomography scanning demonstrated this phenomenon. Mechanisms of additional or distant damage within the brain may include a high deposit of kinetic energy from the penetrating missile, additional vascular damage, and possibly neuronal and axonal degeneration. Widespread and distant brain changes may explain some instances of late neuropsychological and psychiatric dysfunction or rehabilitation failure following a brain wound. Brain imaging should be used to properly evaluate the full extent of brain damage following wounding.