bluuebunny/crossref_metadata_2025 huggingface dataset:
Acute cerebral blood flow response to dopamine-induced hypertension after subarachnoid hemorrhage
Authors: Darby Joseph M. , Yonas Howard , Marks Elizabeth C. , Durham Susan , Snyder Robert W. , Nemoto Edwin M.
Published: May 2009

✓ The effects of dopamine-induced hypertension on local cerebral blood flow (CBF) were investigated in 13 patients suspected of suffering clinical vasospasm after aneurysmal subarachnoid hemorrhage (SAH). The CBF was measured in multiple vascular territories using xenon-enhanced computerized tomography (CT) with and without dopamine-induced hypertension. A territorial local CBF of 25 ml/100 gm/min or less was used to define ischemia and was identified in nine of the 13 patients. Raising mean arterial blood pressure from 90 ± 11 mm Hg to 111 ± 13 mm Hg (p < 0.05) via dopamine administration increased territorial local CBF above the ischemic range in more than 90% of the uninfarcted territories identified on CT while decreasing local CBF in one-third of the nonischemic territories. Overall, the change in local CBF after dopamine-induced hypertension was correlated with resting local CBF at normotension and was unrelated to the change in blood pressure. Of the 13 patients initially suspected of suffering clinical vasospasm, only 54% had identifiable reversible ischemia.

The authors conclude that dopamine-induced hypertension is associated with an increase in flow in patients with ischemia after SAH. However, flow changes associated with dopamine-induced hypertension may not be entirely dependent on changes in systemic blood pressure. The direct cerebrovascular effects of dopamine may have important, yet unpredictable, effects on CBF under clinical pathological conditions. Because there is a potential risk of dopamine-induced ischemia, treatment may be best guided by local CBF measurements.
Accumulation of inositol phosphates in low-passage human meningioma cells following treatment with epidermal growth factor
Authors: Todo Tomoki , Fahlbusch Rudolf
Published: May 2009

✓ In order to elucidate some of the signal transduction processes in human meningioma cells, the authors studied the effect of epidermal growth factor (EGF) and bromocriptine on inositol phospholipid hydrolysis, using low-passage human meningioma cells in culture. Epidermal growth factor is a well-studied mitogenic factor for meningioma cells, whereas bromocriptine is known to have an inhibitory effect on meningioma cell proliferation. The addition of EGF to meningioma cells caused stimulation of inositol phosphate accumulation in a dose-dependent manner at 60 minutes posttreatment, with the maximum effect (120% to 167% of control) achieved at a concentration of 10 ng/ml. Extraction of separate inositol phosphates revealed that inositol monophosphate (IP1) and inositol bisphosphate (IP2), but not inositol trisphosphate (IP3), accounted for the increase at 60 minutes. Kinetic analysis of EGF-stimulated inositol phospholipid hydrolysis showed that a sharp and transient increase in IP3 from 5 to 12 minutes post-EGF and a transient but more gradual increase in IP2 from 2 to 12 minutes post-EGF were followed by a gradual and steady increase in IP1, which was significantly greater than control after 5 minutes. On the other hand, long-term studies showed a down-regulation of inositol phosphate accumulation (a 64% decrease vs. control) after 7 days of treatment with EGF (10 ng/ml). Bromocriptine (5 µM) exhibited no significant effect on inositol phosphate accumulation at 60 minutes in four of five meningiomas studied. However, of two meningiomas studied with bromocriptine in combination with EGF, both showed a significant additive increase in inositol phosphate accumulation compared to those treated with EGF alone. The results suggest a close involvement of inositol phospholipid turnover in human meningioma cells in response to mitogenic stimulation by EGF.
Blood-brain barrier permeability in staphylococcal cerebritis and early brain abscess
Authors: Lo Warren D. , Wolny Arlene , Boesel Carl
Published: May 2009

✓ The pattern of radiographic enhancement in cases of brain abscess has been extensively studied, but the magnitude of blood-brain barrier (BBB) damage that accompanies enhancement has not. The question of whether BBB permeability increases continuously as a cerebritis evolves into an abscess was studied. The tracers 3H-labeled aminoisobutyric acid and 14C-labeled butanol were used in a rat Staphylococcus aureus cerebritis model to measure simultaneously BBB permeability and blood flow. The rats were examined at 1, 2, 3, 5, or 7 days after inoculation, and tissue samples were collected from the cerebritis site and uninoculated regions.

Permeability of the BBB in the cerebritis region increased to five times the normal values by 72 hours after inoculation, then reached a plateau. The plasma volume in the cerebritis region increased to six times greater than the normal value at 72 hours, then remained unchanged. Uninoculated brain in both ipsilateral and contralateral hemispheres showed no significant changes. Cerebral blood flow was not substantially altered at the inoculated or uninoculated sites.

In this model, incidence of BBB damage rises rapidly, reaches a plateau, and does not continue to increase despite the ongoing evolution of a cerebritis into an abscess. The BBB damage is accompanied by an increase in the regional plasma volume, a novel finding that has not been previously reported in central nervous system inflammation. These results suggest that the vascular events contributing to brain edema formation become established early in the cerebritis phase and imply that control of the host's inflammatory response is important in the management of cerebritis-associated brain edema.
Symptomatic lumbar stenosis following fusion using sublaminar hooks
Authors: Myseros John S. , Broaddus William C. , Trumble Eric R. , Adelaar Robert S.
Published: May 2009

✓ A case of postfusion lumbar stenosis caused by the presence of sublaminar hooks is described. The patient was a 52-year-old man who 11 years previously had undergone lumbar fusion with Harrington rod instrumentation for a traumatic L-2 vertebral body fracture. Postoperatively, he developed progressive low-back pain, neurogenic claudication, and significant lower-extremity weakness and atrophy. Upon radiological examination, he was found to have high-grade lumbar stenosis at the level of the caudal sublaminar hooks. The instrumentation was removed and the area of radiological stenosis decompressed. Clinically, both the patient's pain and motor deficits resolved and, on postoperative imaging, the stenosis was relieved. Thus, despite other areas of persisting pathology, it is concluded that the stenosis occurring at the level of the caudal sublaminar hooks contributed to the patient's symptoms. Although not a common cause of postfusion stenosis, the presence of instrumentation in the proximity of neural elements must be considered as an etiology for neurological dysfunction.
Symptomatic lumbar epidural varices
Authors: Zimmerman Gary A. , Weingarten Karen , Lavyne Michael H.
Published: May 2009

✓ Lumbar epidural varices have been infrequently described in the literature and rarely accepted as a primary pathophysiological entity. The authors' total experience with symptomatic lumbar epidural varices over the last 15 years includes four cases (incidence 0.067% of all lumbar spine operations), two of which are described in detail in this paper. The mechanism for their formation is proposed: central disc herniations obstruct the anterior epidural venous flow leading to anterolateral caudal venous distention. Subsequent venous endothelial injury predisposes to varying degrees of phlebothrombosis. Decompression of partially thrombosed varices may occur during operative discectomy or spontaneously during regression of the nonoperated disc prolapse. Regression of the central disc herniation may also explain the “disappearing disc” phenomenon, in which patients with clinical and radiographic evidence of apparently large caudal disc herniations exhibit clinical and radiographic resolution. Magnetic resonance (MR) imaging characteristics of the epidural varix depend upon the degree of thrombosis within this anomaly. A thrombosed varix is hyperintense on T1-weighted, proton-density, and T2-weighted images, whereas flowing blood is hypointense. The variable hypo- and hyperintensity on the T2-weighted MR imaging sequences correlate with a partially patent lumen within the varix.
Melanotic neuroectodermal tumor of infancy in the skull associated with high serum levels of catecholamine
Authors: Hoshino Shigeru , Takahashi Hiroshi , Shimura Toshiro , Nakazawa Shozo , Naito Zenya , Asano Goro
Published: May 2009

✓ The case of a 5-month-old boy with a left retromastoid melanotic neuroectodermal tumor of infancy is presented. The tumor extended from the subcutaneous tissue of the occiput to the cerebellar hemisphere. Histologically, the epidural part of the tumor was composed of undifferentiated neuroblasts, dense connective tissue, and glandular structures lined by melanin-containing cuboidal cells, whereas the subdural part contained differentiated neuroblasts and melanin-containing cells. The preoperative high serum levels of adrenaline, noradrenaline, vanillylmandelic acid, and neuron-specific enolase returned to normal after two operations and two cycles of chemotherapy; however, the dopamine level was mildly elevated. These data and immunohistochemical and ultrastructural findings strongly suggest that melanotic neuroectodermal tumor of infancy is derived from the neural crest.
Superficial siderosis of the central nervous system after brachial plexus injury
Authors: Bonito Virginio , Agostinis Cristina , Ferraresi Stefano , Defanti Carlo Alberto
Published: May 2009

✓ Superficial siderosis is a rare condition characterized by deposition of hemosiderin in the leptomeninges and in the subpial layers of the brain and spinal cord. It is associated with cerebrospinal fluid abnormalities consistent with recurrent bleeding into the subarachnoid space. The usual symptoms are hearing loss, ataxia, spastic paraparesis, sensory and sphincter deficits, and mental deterioration.

A case is presented of severe superficial siderosis of the central nervous system in a 51-year-old man who had suffered a brachial plexus injury at the age of 20 years. The diagnosis was made by means of magnetic resonance imaging 16 years after the initial symptoms, which comprised bilateral hearing loss and anosmia. Subarachnoid bleeding was due to traumatic pseudomeningocele of the brachial plexus, a very unusual cause of superficial siderosis. This case is interesting insofar as the surgical treatment prevented further bleeding and possibly progression of the disease.
Cervical corpectomy and plate fixation for postlaminectomy kyphosis
Authors: Herman James M. , Sonntag Volker K. H.
Published: May 2009

✓ Between 1987 and 1991, 20 patients with symptomatic postlaminectomy kyphosis were treated with anterior decompression, bone graft, and anterior cervical plate. The patients were predominantly male (14:6) with a mean age of 58 years. The initial laminectomy was performed for either spondylosis (80%) or spinal tumor (20%). All patients had anterior compressive pathology, which was associated with instability (45%), neck pain (75%), myeloradiculopathy (90%), or severe neck deformity (30%). The mean degree of kyphosis was 38°. Treatment consisted of a trial of cervical traction (75%), anterior corpectomy (95%), intersegmental decompression (5%), bone fusion (100%), and fixation with either Caspar (85%) or Synthes (15%) anterior plating at a mean of 3.8 levels. Halo fixation was used in 10% of patients. Postoperative complications included vocal cord paresis (15%), pneumonia (10%), wound dehiscence (5%), and screw pull-out (5%). At follow-up evaluation, a mean of 28 months after treatment, all patients had a solid fusion and a mean curvature improvement to 16° residual kyphosis. Neurologically, 10% were cured, 55% were improved and returned to premorbid function, 30% were stable, and 5% had late progression. These data suggest that immediate fixation with anterior plating facilitates solid fusion, maintains spinal curvature, and promotes neurological improvement.
The treatment of chronic thoracic segmental pain by radiofrequency percutaneous partial rhizotomy
Authors: Stolker Robert J. , Vervest Arnoud C. M. , Groen Gerbrand J.
Published: May 2009

✓ Forty-five patients, 12 men and 33 women with an age range of 17 to 88 years (median 52 years), were selected for a posterior thoracic percutaneous partial rhizotomy (PPR) based on the following criteria. Each patient had at least a 6-month history of irradiating pain that followed the segmental pattern of an intercostal nerve and had not responded to conservative treatment. In addition, no causal treatment was available and there was a temporary positive response to an intercostal blockade with lidocaine.

In the lower thoracic region (T8–12) PPR was performed with the usual dorsolateral technique; in the upper thoracic region a dorsal approach was used by means of a drill hole made with a Kirschner wire in the vertebral arch. The 45 patients underwent 53 thoracic PPR operations. Patients were evaluated 2 months after treatment. Thirty patients (66.7%) were pain-free: in 11 cases (24.4%) more than 50% improvement was achieved, and in four (8.9%) there was no improvement. Side effects consisting of a transient burning pain or a mild transient sensory loss occurred in eight patients (17.7%). After a follow-up period of 13 to 46 months (median 24 months) results were evaluated in 41 patients; five patients had undergone reintervention. Excellent long-term results were achieved in 20 patients (48.8%), good results in 15 (36.6%), and poor results in six (14.6%).

It is concluded, that when conservative treatment fails, thoracic PPR may prove an effective and safe treatment for chronic segmental thoracic pain.
The effect of single-application topical ophthalmic anesthesia in patients with trigeminal neuralgia
Authors: Kondziolka Douglas , Lemley Thomas , Kestle John R. W. , Lunsford L. Dade , Fromm Gerhard H. , Jannetta Peter J.
Published: May 2009

✓ To evaluate the reported benefit of ipsilateral single-application ophthalmic anesthetic eyedrops in patients with typical trigeminal neuralgia, a randomized double-blind placebo-controlled trial was performed. Forty-seven patients were randomly assigned to receive two drops of either proparacaine (25 cases) or saline placebo (22 cases). The experimental and placebo groups were equivalent in regard to patient age, distribution of trigeminal neuralgia pain, duration of pain, current medication regimens, and number of prior procedures performed. Pain response was assessed at 3, 10, and 30 days after instillation using two pain rating scales and a measure of pain frequency. Treatment failure was defined in advance as any of the following: a lack of clinical response, the need for an increase in medication, or the need for surgery. No significant difference in outcomes was found between the two groups either when using a verbal pain rating scale (p = 0.24) or when comparing overall pain status (unchanged, improved throughout the study period, or temporarily improved) (p = 0.98). No difference in the frequency of trigeminal neuralgia attacks between the two treatment groups (scaled within five levels of pain frequency) was detected (p = 0.09). During follow-up monitoring, 11 patients in the test drug group and 14 in the placebo group required surgery because of persistent pain (p = 0.24). The results of this study indicate that single-application topical ophthalmic anesthesia reduces neither the severity nor the frequency of pain in comparison to placebo administration. Although a simple and safe treatment, the single application of topical ophthalmic eyedrops provides no short- or long-term benefit to patients with trigeminal neuralgia.
Seizure control following tumor surgery for childhood cortical low-grade gliomas
Authors: Packer Roger J. , Sutton Leslie N. , Patel Kantilal M. , Duhaime Ann-Christine , Schiff Steven , Weinstein Steven R. , Gaillard William D. , Conry Joan A. , Schut Luis
Published: May 2009

✓ Detailed preoperative electroencephalographic (EEG) studies are now recommended for children with seizures and cortical tumors to define seizure foci prior to surgery. To develop a historical perspective for better evaluation of results from series reporting tumor removal combined with resection of seizure foci, the authors reviewed seizure outcome in 60 children with seizures and low-grade neoplasms treated consecutively since 1981 by surgical resection without concomitant EEG monitoring or electrocortical mapping. Forty-seven of the 60 tumors were totally or near-totally resected; 45 patients were seizure-free and two were significantly improved 1 year following surgery. Of the 50 children in this series with more than five seizures prior to surgery, 36 were seizure-free, two were significantly improved, and 12 were not improved. Factors associated with poor seizure control included a parietal tumor location, a partial tumor resection, and a history of seizures for more than 1 year prior to surgery. The children at highest risk for poor seizure control at 2 years had experienced seizures for more than 1 year prior to surgery and had undergone partial resection of their parietal low-grade glial tumors or gangliogliomas. In contradistinction, the best seizure control was seen in patients with totally resected low-grade gliomas or gangliogliomas who had experienced seizures for less than 1 year (concordance rates for being seizure-free ranged from 78% to 86%). Long-term seizure control remained excellent. These results suggest that seizure control can be obtained 2 years following tumor surgery in the majority of children with presumed tumors after extensive tumor resection without concomitant EEG monitoring or electrocortical mapping.
Epithelial cystic lesions of the sellar and parasellar region: a continuum of ectodermal derivatives?
Authors: Harrison Michael J. , Morgello Susan , Post Kalmon D.
Published: May 2009

✓ Cystic epithelial lesions of the sellar and parasellar region are classified on the basis of histology and location into Rathke's cleft cysts, epithelial cysts, epidermoid cysts, dermoid cysts, and craniopharyngiomas. A retrospective review of the clinical presentation, radiological findings, and histology was performed on 19 such lesions, and a survey of the literature pertinent to the classification, clinical presentation, and embryology of these lesions was conducted.

Presentation was nonspecific and not predictive of histology. Imaging studies were generally useful in distinguishing these tumors, with the exception of Rathke's cleft cysts, suprasellar epidermoid cysts, and craniopharyngiomas, which frequently could not be differentiated. On microscopic examination, most lesions fit into distinct categories; however, overlap was common among all and some could not be definitively categorized by histological criteria.

Evidence supportive of an ectodermal ancestry for sellar and parasellar epithelial-lined cystic lesions is presented. Based on the current findings and a review of the literature, it is suggested that these lesions represent a continuum of ectodermally derived cystic epithelial lesions.
Combined approaches for resection of extensive glomus jugulare tumors
Authors: Patel Sunil J. , Sekhar Laligam N. , Cass Stephen P. , Hirsch Barry E.
Published: May 2009

✓ Complete resection with conservation of cranial nerves is the primary goal of contemporary surgery for glomus jugulare tumors. This publication reports the value of combined surgical approaches in achieving this goal in 12 patients with extensive tumors. Eleven of these tumors were classified as Fisch Class C and/or D, while eight were categorized as Jackson-Glasscock Grade III or IV. Intracranial (intradural) extension was present in 10 patients; four patients had tumor extension into the clivus and two into the cavernous sinus. The petrous internal carotid artery (ICA) was involved in eight and the vertebral artery (VA) in one.

Subtemporal-infratemporal, retrosigmoid, and/or extreme lateral transcondylar approaches were added to the usual transtemporal-infratemporal approach. This improved the exposure, provided early control of the petrous ICA, and facilitated tumor removal from the clivus, cavernous sinus, posterior fossa, and foramen magnum, allowing a single-stage resection in eight patients. Ten patients had a complete microscopic resection with no mortality. The facial nerve was preserved in nine cases, with tumor involvement requiring nerve resection followed by grafting in the remaining three. Mobilization of the facial nerve was avoided in five cases; of these, three had intact function and two had House-Brackmann Grade III function on follow-up review. Only one patient had a mild persistent swallowing difficulty. The ICA was preserved in 10 patients and resected in two, while the VA required reconstruction in one case. There were no instances of stroke, and blood transfusions were required in five patients who had tumors with nonembolizable ICA or VA feeders. While complete resection provides the best possibility for cure, the important role of adjuvant radiation therapy in cases with residual tumor is discussed. The importance of degrees of brain-stem compression and vascular encasement is emphasized in classifying the more extensive tumors.
Expression and localization of messenger RNA and protein for monocyte chemoattractant protein-1 in human malignant glioma
Authors: Takeshima Hideo , Kuratsu Jun-Ichi , Takeya Motohiro , Yoshimura Teizo , Ushio Yukitaka
Published: May 2009

✓ Expression of monocyte chemoattractant protein-1 (MCP-1) in human glioma cell lines and surgical specimens was studied by Northern blot analysis, reverse-transcription polymerase chain reaction,in situhybridization, and immunohistochemistry. The samples tested consisted of 11 human glioma cell lines and eight specimens of human malignant glioma (seven from glioblastomas and one from a malignant ependymoma).

Messenger ribonucleic acid (mRNA) of MCP-1 was detected by either Northern blot or reverse-transcription polymerase chain reaction analysis in all cell lines and tumor specimens examined.In vivoexpression of MCP-1 mRNA and protein was found predominantly in glioma cells with large and pleomorphic nuclei rather than in areas of small nucleated glioma cells. Adjacent brain tissue did not produce a significant level of MCP-1 mRNA or protein. Tumor vessels with endothelial proliferation expressed a moderate level of MCP-1 protein. Macrophages were found among the glioma cells, and the degree of macrophage infiltration was grossly correlated with the level of MCP-1 expression. The study results suggest that MCP-1 produced by the glioma cells may mediate macrophage infiltration into the glioma tissue.
Lhermitte-Duclos disease mimicking adult-onset aqueductal stenosis
Authors: Siddiqi Shah N. , Fehlings Michael G.
Published: May 2009

✓ Lhermitte-Duclos disease is a rare lesion characterized by enlarged cerebellar folia containing abnormal ganglion cells. This case report describes a 51-year-old woman who was initially misdiagnosed as having adult-onset aqueductal stenosis. There were no abnormal findings on computerized tomography (CT), but subsequent magnetic resonance (MR) imaging showed a midline cerebellar lesion extending to the brain stem. This is a unique case of Lhermitte-Duclos disease arising within the cerebellar vermis. The characteristic feature of an enlarged cerebellar hemisphere is absent on CT scans; thus MR imaging is needed to confirm the diagnosis. If diagnosed late, this generally benign lesion becomes difficult to resect totally and has a poorer prognosis. Only two reports have mentioned the MR imaging characteristics of Lhermitte-Duclos disease; both described only T2-weighted images. This case illustrates the full spectrum of MR imaging features of this disease. Both T1- and T2-weighted studies showed enlarged cerebellar folia within the lesion. The T1-weighted image showed a mixed iso- and hypodense signal and the T2-weighted image a homogeneously increased signal; with gadolinium administration the lesion did not enhance. The latter feature supports the theory that this disease is a hamartoma rather than a tumor.
“Acquired” Chiari I malformation
Authors: Huang Paul P. , Constantini Shlomo
Published: May 2009

✓ Tonsillar descent of the cerebellum in Chiari I malformations is often considered a congenital defect. A patient is presented in whom magnetic resonance (MR) imaging revealed normally positioned cerebellar tonsils; however, 1 year later MR imaging was repeated for evaluation of gait abnormalities and showed descent of the cerebellar tonsils. This case illustrates worsening symptoms with progressive descent of the cerebellar tonsils and suggests that Chiari I malformations can evolve postnatally.
Treatment of invasive growth hormone pituitary adenomas with long-acting somatostatin analog SMS 201–995 before transsphenoidal surgery
Authors: Lucas-Morante Tomás , García-Uría José , Estrada Javier , Saucedo Gertrudis , Cabello Ana , Alcañiz Julián , Barceló Balbino
Published: May 2009

✓ The purpose of this study was to determine whether the long-acting somatostatin analog SMS 201–995 (octreotide) shrinks growth hormone (GH)-secreting adenomas and improves the results of subsequent transsphenoidal surgery. Ten previously untreated active acromegalic patients (nine women and one man) with invasive tumors were treated with SMS 201–995 (100 µg subcutaneously every 8 hours) for 6 weeks prior to transsphenoidal surgery. The clinical activity, mean GH secretion, insulin-like growth factor (IGF)-I concentration, and tumor volume were measured under basal conditions and on Days 14, 28, and 42 of treatment.

The SMS 201–995 improved the symptoms of acromegaly in all patients. Mean levels of both GH and IGF-I (± standard deviation) were significantly decreased by Day 14 (from 92.9 ± 30.5 to 44.9 ± 20.3 µg/liter and from 10.6 ± 7.4 to 5.9 ± 2.6 U/ml, respectively), after which there were only slight further decreases. Six (60%) of the 10 patients experienced tumor shrinkage ranging from 9% to 78% (mean 30%). When it occurred, tumor shrinkage was significant by Day 14 (7.9 ± 6.3 to 6.5 ± 5.1 cu cm) and no further shrinkage was achieved by longer administration. Transsphenoidal surgery reduced postoperative GH levels to less than 2 µg/liter and IGF-I to less than 1.5 U/ml in six patients (60%). This percentage of cure is higher than expected from the literature and the authors' previous experience. However, an investigation of the influence of this drug on several parameters, such as reduction of tumor size or GH and IGF-I concentrations, has failed to prove any relationship. Only pretreatment size of the tumor was of predictive value with respect to the surgical outcome.
Extracerebral fluid collections in infancy: role of magnetic resonance imaging in differentiation between subdural effusion and subarachnoid space enlargement
Authors: Aoki Nobuhiko
Published: May 2009

✓ The pathological process of extracerebral fluid collections in infancy includes subdural effusion and enlargement of the subarachnoid spaces. Both conditions have traditionally been investigated as a single clinical entity, because of difficulty in differentiating between them. The prognosis of subdural effusion is not as benign as that of enlargement of subarachnoid spaces, requiring differential diagnosis between these disorders. The present study was conducted to elucidate whether this differentiation could be made on magnetic resonance (MR) images.

The series consisted of 16 infants aged 10 months or younger, including eight with verified subdural effusion and eight in whom a diagnosis of enlargement of the subarachnoid spaces was achieved by neuroimaging studies other than MR imaging. In all eight patients with subdural effusion, the intensity of the fluid was greater than that of cerebrospinal fluid (CSF) in at least one of the sequences using T1-weighted, proton-density, and T2-weighted MR images. The flow-void sign, indicating vessels in the fluid spaces, was not seen in any of these eight patients. On the other hand, in all eight patients with enlargement of the subarachnoid spaces, the fluid was isointense in relation to CSF, and vascular flow-void areas were seen in at least one of the MR imaging sequences. Based on these observations, it is concluded that differentiation between subdural effusion and enlargement of the subarachnoid spaces can be established by focusing on two aspects of MR imaging findings: 1) the intensity of the fluid, which is either iso- or hyperintense relative to CSF, and 2) the presence or absence of vascular flow-void areas in the fluid spaces.
Reoperation for recurrent temporal lobe epilepsy
Authors: Germano Isabelle M. , Poulin Nicole , Olivier André
Published: May 2009

✓ The indications for and the risks and outcome of reoperation for medically refractory temporal lobe epilepsy have not been well documented. A retrospective review is presented of 40 patients who underwent reoperation on the temporal lobe for recurrent seizures. The mean patient age at the first operation was 22 ± 7 years (± standard deviation). Electrocorticography during the first operation showed interictal epileptic abnormalities from surface electrodes in 97% of the cases and from depth electrodes in the mesiotemporal structures in 38%. The seizures recurred with the same pattern within 6 months after the first operation in 60% of patients and within 2 years in 90%. Postoperative neuroimaging studies showed residual mesiotemporal structures in all cases. The mean time between the two operations was 5.5 ± 5 years and the mean patient age at the second operation was 28 ± 8 years. The second operation involved focal resection of the mesiotemporal structures in 30 cases. The mean postoperative follow-up period was 4.8 ± 2.7 years (range 2 to 11 years). After the second operation, 63% of the patients were seizure-free or had rare seizures (one or two per year). There were no permanent neurological complications. Patients who did not benefit from reoperation had electroencephalographic abnormalities in multiple brain areas.

Reoperation for temporal lobe epilepsy effectively controls seizures in the majority of patients, and the procedure is safe if rigorous technical rules are observed. More complete resection of mesiotemporal structures during the first operation, even in the absence of intraoperative electrographic abnormalities, could prevent the need for reoperation in defined cases.
The role of hemispherectomy in the treatment of holohemispheric hemimegaloencephaly
Authors: Taha Jamal M. , Crone Kerry R. , Berger Thomas S.
Published: May 2009

✓ The role of hemispherectomy in treating holohemispheric hemimegaloencephaly, a unilateral brain malformation, is still not well defined. The authors describe the cases of five infants presenting with intractable seizures, progressive neurological deficits, and severe developmental delay. Electroencephalography (EEG) showed generalized polyspikes from the megaloencephalic hemisphere and progressive slowing on the opposite side in all children; contralateral seizure spikes occurred in three children. Three of the five children underwent hemispherectomy for intractable seizures before 2 years of age, after which the seizures subsided completely in two children and improved remarkably in the third. Preoperative Wada testing proved useful in evaluating pharmacologically the effect of hemispherectomy on contralateral polyspikes. Postoperative EEG revealed the absence of polyspikes in the operated hemisphere and decreased slowing on the contralateral side. Psychomotor development in the surgically treated infants exceeded that of the children not undergoing hemispherectomy. Of the two children treated medically, one died at 4 years of age in status epilepticus and the other (now 5 years old) has frequent seizures and severe developmental delay.

Based on these results, hemispherectomy appears to be a useful procedure for controlling seizures and improving psychomotor development in children with hemimegaloencephaly involving the entire hemisphere. Surgery in infancy can prevent or minimize seizure foci and encephalopathic changes that may develop in the contralateral hemisphere. Staging the procedure and exercising meticulous hemostasis make surgery relatively safe in infants who otherwise may have significant blood loss associated with increased blood flow to the megaloencephalic hemisphere.
Cervicomedullary compression in achondroplasia
Authors: Ryken Timothy C. , Menezes Arnold H.
Published: May 2009

✓ Six patients with achondroplasia and symptoms suggestive of cervicomedullary junction compression are reviewed; these included three females and three males, with an average age of 8 years (range 7 months to 30 years). The mean duration of symptoms prior to intervention was 1.9 years. Symptoms included occipitocervical pain, ataxia, incontinence, apnea, and respiratory arrest. Radiological investigations consisted of plain films with flexion and extension views, pluridirectional tomography, thin-section computerized tomography, and magnetic resonance imaging. Typical findings included marked foramen magnum stenosis, ventrolateral cervicomedullary junction compression secondary to central and paramesial basilar invagination, and dorsal cervicomedullary junction compression secondary to ligamentous hypertrophy and invagination of the posterior atlantal arch. All patients underwent posterior fossa decompression and atlantal laminectomy. Surgery consistently revealed marked dorsal and paramesial overgrowth of the rim of the foramen magnum, with thickening and invagination of the atlantal posterior arch and a dense fibrotic epidural band resulting in dorsal cervicomedullary compression. Intraoperative ultrasonography was used to determine the extent of decompression required.

Three patients required duraplasty. Three patients had concurrent hydrocephalus, two of whom had undergone ventriculoperitoneal shunting prior to surgical decompression of the posterior fossa. One patient developed a pseudomeningocele postoperatively, requiring serial lumbar punctures before it resolved. No patient developed craniovertebral instability following decompression. Improvement or resolution of symptoms was noted in all patients, with an average follow-up period of 4.8 years. Thus, cervicomedullary compression in patients with achondroplasia can be successfully treated with dorsal decompression of the craniovertebral junction. Dense epidural fibrotic bands are frequently noted in these cases and must be aggressively released to ensure satisfactory decompression.
Extreme lateral transcondylar approach: technical improvements and lessons learned
Authors: Babu Ramesh P. , Sekhar Laligam N. , Wright Donald C.
Published: May 2009

✓ An extreme lateral transcondylar or extreme lateral transfacetal surgical approach was used to treat 22 patients with complex lesions over a 22-month period. The lesions included basilar invagination with vertebral artery pathology, giant aneurysm or arteriovenous fistula of the vertebral artery, meningioma, chordoma, chondrosarcoma, and paraganglioma. The approach was used alone or in combination with a presigmoid petrosal or subtemporal-infratemporal approach. Refinements of the operative technique, treatment strategies for complex lesions, and the avoidance of complications are discussed.

Complications included cerebrospinal fluid leakage, meningitis, pseudomeningocele, hemiparesis or quadriparesis, lower cranial nerve deficits, and vertebral artery injury requiring repair. With treatment, major neurological deficits resolved completely in three patients and partially in two. There was no operative mortality, but four patients died during the follow-up period. For the 18 surviving patients, the mean preoperative and postoperative Karnofsky scores were 81 and 93, respectively. For the four who died, the mean preoperative Karnofsky score was 73 and the mean postoperative score was 63.
Transcranial approach to the orbit: microsurgical anatomy
Authors: Natori Yoshihiro , Rhoton Albert L.
Published: May 2009

✓ An anatomical study of three microsurgical intraorbital routes to the optic nerve and orbital apex, which can be reached through a fronto-orbital craniotomy, was conducted on cadaver specimens. The structures that could be exposed via the medial, central, or lateral approaches directed through the orbital roof were defined. The medial approach, directed through the space between the superior oblique and the levator muscles, provides good access to all parts of the intraorbital optic nerve. The central approach, between the levator and the superior rectus muscles, provides the shortest route to the optic nerve. Two variants of the central approach were examined. In the first, the levator muscle and frontal nerve are retracted medially and the superior rectus muscle laterally. This variant provides access to only the midportion of the intraorbital segment of the optic nerve. In the second variant, the frontal nerve is retracted laterally together with the superior rectus muscle. This variant provides access to the posterior two-thirds of the intraorbital portion of the optic nerve.

The lateral approach is directed between the levator and lateral rectus muscles. This approach also has two variants, depending on whether the superior ophthalmic vein is retracted medially or laterally. The variant in which the superior ophthalmic vein is retracted medially with the levator and superior rectus muscles provides access to the lateral side of the optic nerve except in the region adjacent to the superior orbital fissure. The variant in which the superior ophthalmic vein is retracted laterally together with the lateral rectus muscle provides excellent access to the optic nerve in the region of the superior orbital fissure. It is an ideal approach for lesions that involve both the cavernous sinus and orbit.
Stenosis of the central canal of the spinal cord following inoculation of suckling hamsters with reovirus type I
Authors: Milhorat Thomas H. , Kotzen René M.
Published: May 2009

✓ The central canal of the human spinal cord is partially or completely occluded in the vast majority of individuals by the early years of adult life. The authors describe an experimental lesion following virus-induced ependymitis that bears a striking resemblance to the condition in man. Suckling hamsters were inoculated with 0.06 ml of 10−3infectivity titer of reovirus type I between the 2nd and 5th days of life. The pathological events consisted of necrotizing ependymitis, healing of the ependyma by gliovascular scarring, and obstruction of narrow bottlenecks such as the central canal. Histological findings were characterized by disorganization of the ependyma, formation of ependymal rosettes and microtubules, subependymal gliovascular scarring, and intracanalicular gliosis. These features are the same as those encountered clinically and provide strong evidence that stenosis of the central canal in man is a pathological lesion involving ependymal injury and scarring.
Primary empty sella in association with superior sagittal sinus thrombosis and dural arteriovenous malformation
Authors: Haisa Toshihiko , Yoshida Shinichi , Ohkubo Toshiyuki , Yoshikawa Kohki , Machida Tohru
Published: May 2009

✓ A 61-year-old woman under treatment with oral medroxyprogesterone acetate following surgery for breast cancer developed diplopia and papilledema due to raised intracranial pressure (ICP). Radiological studies disclosed an empty sella turcica, a dural arteriovenous malformation (AVM), and superior sagittal sinus thrombosis. The sinus thrombosis was considered to have been a side effect of the medroxyprogesterone acetate medication. The association between a primary empty sella and raised ICP is briefly discussed, along with the cause-and-effect relationship between a dural AVM and venous sinus thrombosis.
Hypothalamic chordoma
Authors: Commins Deborah , Baran Gregg A. , Molleston Michael , Vollmer Dennis
Published: May 2009

✓ The case is reported of a 51-year-old woman found to have a hypothalamic mass with the histological features typical of chordoma. This represents the first description of a chordoma arising within the brain.
Basilar artery dissection: an early postoperative complication of aneurysm clipping
Authors: Toyota Brian D. , Ferguson Gary G.
Published: May 2009

✓ Recurrent subarachnoid hemorrhage (SAH) in the early period following successful clipping of a cerebral aneurysm is unusual. The authors report a unique case of distal basilar artery dissection and fatal SAH on the 6th day postoperatively. It is concluded that this complication was related to vascular trauma inflicted by repositioning the aneurysm clips during a seemingly uneventful procedure for a basilar artery tip aneurysm.
Treatment of high-dose intrathecal morphine overdose
Authors: Sauter Kent , Kaufman Howard H. , Bloomfield Stephen M. , Cline Sandi , Banks Daniel
Published: May 2009

✓ The case is reported of a 45-year-old woman who was being treated for chronic back and right leg pain with intrathecal morphine administered via a subcutaneous continuous-infusion device. She received an accidental 450-mg bolus injection of morphine intrathecally and developed hypertension, status epilepticus, intracerebral hemorrhage, and respiratory failure. Treatment with continuous intravenous naloxone infusion, lumbar catheter drainage of cerebrospinal fluid, and control of hypertension and status epilepticus resulted in an excellent outcome with return to neurological baseline. Care providers who refill pump reservoirs with morphine must be knowledgeable about these devices and the life-threatening consequences associated with errors in refilling them. This case describes the complications and successful treatment of high-dose intrathecal morphine overdose.
Temporal profile of outcomes in severe head injury
Authors: Choi Sung C. , Barnes Thomas Y. , Bullock Ross , Germanson Teresa A. , Marmarou Anthony , Young Harold F.
Published: May 2009

✓ The authors present data describing the temporal progress of 786 severely head-injured patients from discharge to 12 months postinjury. Changes in outcome over time are characterized and the effects on these changes of patient age, Glasgow Coma Scale score, pupillary response, and type of injury are investigated. The feasibility of using these factors and the outcome at 3 months postinjury to predict the outcome at 6 months posttrauma is explored via logistic regression analysis. The data indicate that a significant proportion of patients improve continuously during the first 6 months after injury; outcome tends to stabilize thereafter, which suggests that the response at this time may be the appropriate end point for clinical trials in severe head injury. Dichotomized outcomes are predictable with approximately 94% accuracy at 6 months postinjury; therefore, missing outcomes may safely be replaced by the corresponding predicted outcomes. The findings also indicate striking improvement over time in patients who are in a vegetative state at discharge, suggesting that decisions regarding withdrawal of supportive care should be postponed until 6 months after injury in these patients.
Cerebrospinal fluid edema associated with shunt obstruction
Authors: Sakamoto Hiroaki , Fujitani Ken , Kitano Shouhei , Murata Keiji , Hakuba Akira
Published: May 2009

✓ The authors report four hydrocephalic children with cerebrospinal fluid (CSF) edema extending along the ventricular catheter of an obstructed CSF shunt. Three of the patients exhibited massive CSF edema along the ventricular catheter, yet they manifested neither ventricular enlargement nor apparent periventricular CSF edema despite increased intraventricular pressure. These findings suggested ventricular tautness. The remaining patient, who had dilated ventricles with periventricular CSF edema, displayed CSF edema in a limited area along the ventricular catheter. Replacement of the obstructed peritoneal catheter of the shunt resulted in rapid improvement of the edema in all patients. In the three patients with massive CSF edema, however, a small lesion remained in the subcortical white matter along the ventricular catheter as demonstrated by computerized tomography and/or magnetic resonance imaging 3 to 5 years after shunt revision. It is concluded that shunt obstruction may result in massive CSF edema along the ventricular catheter in hydrocephalic children who have ventricular tautness after installation of the shunt causing irreversible although usually asymptomatic damage to the affected area of the brain.
Preirradiation methotrexate chemotherapy of primary central nervous system lymphoma: long-term outcome
Authors: Glass Jon , Gruber Michael L. , Cher Lawrence , Hochberg Fred H.
Published: May 2009

✓ The treatment of primary central nervous system lymphoma with chemotherapy prior to whole-brain radiation therapy (WBRT) has improved outcome considerably in this previously fatal disease. Complete or partial responses to intravenous methotrexate (3.5 gm/sq m with leucovorin rescue every 3 weeks for two to four cycles) were seen in 12 of 13 patients originally treated. A total of 25 patients (including the original 13) have now been treated with one to six cycles of methotrexate every 10 to 21 days prior to WBRT. Twenty-two had partial or complete responses, with a median duration of response of 32 months. Median survival time was 33 months (42.5 months in those responding to therapy). Nine patients are alive and without evidence of disease 9 to 122 months following therapy. Acute and long-term toxicities were minimal. Systemic methotrexate administration prior to WBRT is well tolerated and produces long-term survival.
Improvement of cerebrovascular reserve capacity by EC-IC arterial bypass surgery in patients with ICA occlusion and hemodynamic cerebral ischemia
Authors: Schmiedek Peter , Piepgras Axel , Leinsinger Gerda , Kirsch Carl-Martin , Einhäupl Karl
Published: May 2009

✓ Since the negative results of the international Bypass Study, extracranial-intracranial (EC-IC) bypass surgery is infrequently employed in the treatment of patients with cerebral ischemia. Newly acquired evidence concerning the pathophysiology of cerebral ischemia, however, has facilitated the identification of a small subgroup of patients with “hemodynamic” cerebral ischemia. Characteristically, these patients demonstrate severely impaired cerebrovascular reserve capacity due to occlusive disease and insufficient collateral blood supply.

Over an 8-year period, 28 patients were defined by clinical and laboratory criteria as suffering from hemodynamic cerebral ischemia. All patients had recurring episodes of focal cerebral ischemia due to unilateral internal carotid artery occlusion. Computerized tomography (CT) scans either were normal or showed evidence of border zone infarction. The cerebrovascular reserve capacity was studied using 133Xe single-photon emission CT and acetazolamide challenge and was found to be significantly impaired in all patients. Based on these criteria, superficial temporal artery-middle cerebral artery anastomosis was performed to augment collateral flow to the ischemic hemispheres. Two patients died from myocardial infarction, one 4 days and the other 2 months postoperatively. One patient died from massive brain infarction and another suffered a postoperative stroke with incomplete recovery, resulting in a major morbidity and mortality rate of 14%. Minor morbidity included one patient with a subdural hematoma who subsequently recovered completely. The postoperative course was uneventful in 23 patients (82%). Over a mean follow-up period of almost 3 years, no patient had another episode of brain ischemia. Bypass patency was confirmed by postoperative angiography in 26 patients. Follow-up studies of cerebral blood flow (CBF) and cerebrovascular reserve capacity showed significant improvement of the latter while the resting CBF was essentially unchanged. In view of these findings, the authors conclude that EC-IC bypass surgery constitutes appropriate therapy for a subgroup of patients with recurrent focal cerebral ischemia, defined using the strict selection criteria employed in this study.