bluuebunny/crossref_metadata_2025 huggingface dataset:
Spontaneous spinal cerebrospinal fluid leaks and intracranial hypotension
Authors: Schievink Wouter I. , Meyer Fredric B. , Atkinson John L. D. , Mokri Bahram
Published: June 2009

✓ Spinal cerebrospinal fluid (CSF) leaks are often implicated as the cause of the syndrome of spontaneous intracranial hypotension, but they have rarely been demonstrated radiographically or surgically. The authors reviewed their experience with documented cases of spinal CSF leaks of spontaneous onset in 11 patients including their surgical observations in four of the patients.

The mean age of the six women and five men included in the study was 38 years (range 22–51 years). All patients presented with a postural headache; however, most had additional symptoms, including nausea, emesis, sixth cranial-nerve paresis, or local back pain at the level of the CSF leak. All patients underwent indium-111 radionucleotide cisternography or computerized tomographic (CT) myelography. The location of the spontaneous CSF leak was in the cervical spine in two patients, the cervicothoracic junction in three patients, the thoracic spine in five patients, and the lumbar spine in one patient. The false negative rate for radionucleotide cisternography was high (30%). Subdural fluid collections, meningeal enhancement, and downward displacement of the cerebellum, resembling a Chiari I malformation, were commonly found on cranial imaging studies. In most patients, the symptoms resolved in response to supportive measures or an epidural blood patch. Leaking meningeal diverticula were found to be the cause of the CSF leak in four patients who underwent surgery. In three patients these diverticula could be ligated with good result but in one patient an extensive complex of meningeal diverticula was found to be inoperable. Two patients had an unusual body habitus and joint hypermobility, and two other patients had suffered a spontaneous retinal detachment at a young age.

In conclusion, spontaneous spinal CSF leaks are uncommon, but they are increasingly recognized as a cause of spontaneous intracranial hypotension. Most spinal CSF leaks are located at the cervicothoracic junction or in the thoracic spine, and they may be associated with meningeal diverticula. The radiographic study of choice is CT myelography. The disease is usually self-limiting, but in selected cases our experience with surgical ligation of leaking meningeal diverticula has been satisfactory. An underlying connective tissue disorder may be present in some patients with a spontaneous spinal CSF leak.
Aneurysmal subarachnoid hemorrhage in a patient with bilateral A1 fenestrations associated with an azygos anterior cerebral artery
Authors: Friedlander Robert M. , Ogilvy Christopher S.
Published: June 2009

✓ Fenestration of the proximal anterior cerebral artery (A1 segment) is a rare occurrence. This vascular anomaly is often associated with aneurysms and other abnormalities. The current article describes the case of a 33-year-old man who presented with a subarachnoid hemorrhage secondary to a ruptured aneurysm originating from the proximal end of an A1 fenestration. This patient also had a contralateral A1 fenestration as well as an azygos anterior cerebral artery. This is the first report of such an unusual vascular anatomy. The literature is reviewed and possible embryological mechanisms are discussed.
Paradoxical aggravation of vasospasm with papaverine infusion following aneurysmal subarachnoid hemorrhage
Authors: Clyde Brent L. , Firlik Andrew D. , Kaufmann Anthony M. , Spearman MichaelP. , Yonas Howard
Published: June 2009

✓ Reports of intraarterial papaverine infusion as treatment for cerebral vasospasm are few and documented complications are uncommon. The authors report the case of a patient with paradoxical aggravation of cerebral arterial narrowing during selective intraarterial papaverine infusion intended to treat vasospasm following aneurysmal subarachnoid hemorrhage (SAH). A 48-year-old man presented to the authors' service with symptomatic vasospasm 10 days after experiencing an SAH. The ruptured anterior communicating artery aneurysm was surgically obliterated the following day, and thereafter maximum hypervolemic and hypertensive therapies were used. However, the patient remained lethargic, and a stable xenon—computerized tomography (CT) cerebral blood flow (CBF) study revealed CBF to be 15 cc/100 g/minute in the left anterior cerebral artery (ACA) and 25 cc/100 g/minute in the right ACA territories. Cerebral arteriography demonstrated diffuse severe left ACA and mild left middle cerebral artery (MCA) vasospasm. In response intraarterial papaverine was infused into the internal carotid artery just proximal to the ophthalmic artery. During the infusion the patient became aphasic and exhibited right hemiplegia. Arteriography performed immediately after the intraarterial papaverine infusion revealed diffuse exacerbation of vasospasm in the distal ACA and MCA territories. A repeat xenon—CT CBF study showed that CBF in the left ACA and the MCA had drastically decreased (2 cc/100 g/minute and 10 cc/100 g/minute, respectively). Despite aggressive management, infarction ultimately developed.

This is the first clinical case to illustrate a paradoxical effect of intraarterial papaverine treatment for vasospasm following aneurysmal SAH. The possible mechanisms of this paradoxical response and potential therapeutic reactions are reviewed.
Central neurocytoma: proliferative potential and biological behavior
Authors: Kim Dong Gyu , Kim Jong Soo , Chi Je G. , Park Sung Hye , Jung Hee-Won , Choi Kil Soo , Han Dae Hee
Published: June 2009

✓ The authors analyzed 13 central neurocytomas diagnosed at Seoul National University Hospital between January 1982 and December 1993 to clarify the proliferative potential and biological behavior of these tumors. The tumor was confined to the lateral and third ventricles in 12 cases and in one case extended from the posterior thalamus to the body and trigone area of the lateral ventricle. In all 13 cases, typical clinical and radiological findings were observed, and histological diagnosis was performed via craniotomy. The diagnosis was made using light microscopic examination, immunohistochemical staining for neuronal markers, and electron microscopic findings of neuronal differentiation. One patient died due to tumor progression with recurrence 26 months after subtotal removal plus radiation therapy. Another patient had a recurrence 18 months after total tumor removal. The remaining 11 patients are free of recurrent tumor after a follow-up period that ranged from 14 to 109 months (median 50 months). To predict the proliferative potential, immunoreactivity to proliferating cell nuclear antigen (PCNA), silver colloid staining for nucleolar organizing regions (AgNORs), and DNA flow cytometry were performed in 10 of the 13 cases. The proportion of PCNA-positive cells was less than 1% in all cases and the AgNORs score ranged from 1.11 to 2.0 (mean 1.67). The DNA flow cytometry revealed diploidy in all cases and the calculated proliferation index ranged from 5.1% to 9.6% (mean 7.8%). The one case of tumor recurrence, in which the authors performed the study of proliferative potential, and another case that demonstrated mild nuclear pleomorphism also showed low percentages of PCNA-positive cells, low AgNORs scores, and diploidy in DNA flow cytometry.

It is suggested that most central neurocytomas follow a benign clinical course with low proliferative potential assessed by PCNA, AgNORs, and DNA flow cytometry; however, recurrence is possible within a relatively short time period.
Molecular genetic investigation of the neurofibromatosis type 2 tumor suppressor gene in sporadic meningioma
Authors: Harada Takehiko , Irving Richard M. , Xuereb John H. , Barton David E. , Hardy David G. , Moffat David A. , Maher Eamonn R.
Published: June 2009

✓ The authors investigated the role of somatic mutations of the neurofibromatosis type 2 (NF2) gene in sporadic meningioma. Neurofibromatosis 2 is a dominantly inherited familial tumor syndrome predisposing affected patients to a variety of central nervous system tumors including vestibular schwannoma and meningioma. Neurofibromatosis type 2 is caused by germline mutations in the NF2 tumor suppressor gene. In addition, the authors and others have reported that somatic NF2 gene mutations occur frequently in nonfamilial vestibular schwannoma. In this study, molecular genetic analysis was performed on 23 nonfamilial meningiomas. Paired DNA samples extracted from the blood and tumors of the patients were analyzed for loss of heterozygosity (LOH) in the region of the NF2 gene on chromosome 22 using closely linked DNA markers. The NF2 gene mutations were sought by single-stranded conformation polymorphism analysis and DNA sequencing. Fourteen (61%) of 23 meningiomas showed LOH in the region of the NF2 gene on chromosome 22. Somatic NF2 gene mutations were detected in eight meningiomas (35%) after screening all 17 exons. All tumors with NF2 gene mutations showed simultaneous chromosome 22 LOH. Review of the histopathological findings of the cases studied did not demonstrate any predominance of genetic abnormalities in a particular histological type of meningioma. These results are compatible with the hypothesis that the NF2 gene acts as a tumor suppressor and that its inactivation is important in the pathogenesis of sporadic meningioma.
Autocrine growth stimulation of human meningioma cells by platelet-derived growth factor
Authors: Todo Tomoki , Adams Eric F. , Fahlbusch Rudolf , Dingermann Theodor , Werner Herbert
Published: June 2009

✓ The authors have previously shown that meningioma-derived conditioned medium profoundly stimulates the in vitro proliferation of meningioma cells. In this paper, self-mitogenic agents found in the conditioned medium—autocrine growth-stimulatory factors actually secreted by human meningioma cells—are characterized as proteins related to the B chain of platelet-derived growth factor (PDGF) and possibly to the A chain of PDGF as well. The addition to conditioned medium of a neutralizing antibody against PDGF-BB caused a significant inhibition of the conditioned medium—stimulated DNA synthesis in all three meningioma cultures studied. A similar neutralizing effect was observed with an anti—PDGF-AA antibody in one meningioma culture studied. Gel filtration chromatography of concentrated conditioned medium from two different meningiomas using a Sephadex G-100 column revealed similar profiles from both conditioned media with a major peak of mitogenic activity against meningioma cells at a molecular weight (Mr) of approximately 32 to 36 kD, accompanied by a minor peak at approximately 22 kD. The major peak mitogenic activity was significantly reduced by addition of an anti—PDGF-BB antibody. Western blot analysis of protein extracts from five meningioma specimens was performed using a monoclonal antibody against the B chain of PDGF, and a major band of PDGF-B immunoreactivity was detected at an Mr of approximately 19 kD in all five meningiomas under both reducing and nonreducing conditions. Exogenous human and porcine PDGFs both exhibited a significant dose-dependent stimulation of DNA synthesis in two of three and three of five meningioma cultures examined, respectively. Although not all meningiomas investigated proved to share the biological activity associated with PDGF and these results may be preliminary, it seems that the autocrine growth-stimulatory loop established by PDGF-B—related molecules plays an important functional role in meningioma cell proliferation.
Dose escalation safety and tolerance study of the N-methyl-d-aspartate antagonist dextromethorphan in neurosurgery patients
Authors: Steinberg Gary K. , Bell Teresa E. , Yenari Midori A.
Published: June 2009

✓ Experimental studies have shown that dextromethorphan, a noncompetitiveN-methyl-d-aspartate antagonist is neuroprotective in experimental models of ischemic cerebral injury. The authors studied the safety and tolerability of oral dextromethorphan (DM) in humans, and correlated serum levels of this drug with cerebrospinal fluid (CSF) and brain levels. Neurosurgical patients undergoing intracranial surgery or endovascular procedures were given ascending doses of oral DM prior to and 24 hours after surgery. Serum, CSF, and brain levels of DM and its active metabolite, dextrorphan, were measured. One hundred eighty-one patients received a total of 212 courses of DM treatment in dose ranges of 0.8 to 9.64 mg/kg. Serum DM levels correlated highly with CSF and brain DM levels. Brain levels were 68-fold higher than serum levels, whereas CSF levels were fourfold lower than serum levels. The maximum DM levels attained were 1514 ng/ml (serum), 118 ng/ml (CSF), and 92,700 ng/g (brain). The maximum dextrorphan levels were 501 ng/ml (serum), 167 ng/ml (CSF), and 6840 ng/g (brain). In 11 patients, brain and plasma levels of DM were comparable to levels that have been shown to be neuroprotective in animal studies. Frequent side effects occurring at neuroprotective levels of DM included nystagmus (64%), nausea and vomiting (27%), distorted vision (27%), feeling “drunk” (27%), ataxia (27%), and dizziness (27%). All symptoms were reversible and no patient suffered severe adverse reactions. This study demonstrates that potentially neuroprotective doses of DM can be administered safely to neurosurgical patients. Brain and CSF levels of DM can be estimated from serum levels of the drug. Side effects, even at the highest levels, proved to be tolerable and reversible. Administration of DM to patients at risk for cerebral injury should be further explored.
Acute presentation of a neurogenic sarcoma in a patient with neurofibromatosis type 1: a pathological and molecular explanation
Authors: Feldkamp Matthias M. , Lau Nelson , Provias John P. , Gutmann David H. , Guha Abhijit
Published: June 2009

✓ Neurofibromatosis type 1 (NF1) is the most common familial cancer-predisposing syndrome in humans, for which the gene (NF1) and its gene product (neurofibromin) have been identified. The majority of tumors occurring in patients with NF1 are benign neurofibromas; sarcomatous transformation is uncommon and most often occurs within the larger plexiform neurofibromas. Such malignant transformation in a known neurofibroma is often heralded by either radiological evidence of growth or a progression in clinical symptoms (pain and neurological deficit). This progression in symptoms is usually gradual in onset, typically occurring over a period of months. In this report the authors document a neurogenic sarcoma presenting with rapid clinical and radiological growth. The pathological basis of this acute presentation was increased cellular proliferation, with invasion of blood vessels resulting in tumor infarction. The molecular basis of neurofibroma development in NF1 is loss of expression of the NF1 gene and its gene product, neurofibromin, resulting in elevated levels of Ras—guanosine triphosphate. Subsequent molecular events result in sarcomatous transformation.
Chronic encapsulated expanding hematoma in association with gamma knife stereotactic radiosurgery for a cerebral arteriovenous malformation
Authors: Kurita Hiroki , Sasaki Tomio , Kawamoto Syunsuke , Taniguchi Makoto , Kitanaka Chifumi , Nakaguchi Hiroshi , Kirino Takaaki
Published: June 2009

✓ The authors report a rare case of a patient with a chronic encapsulated expanding hematoma and progressive neurological deterioration who presented 2 years after gamma knife radiosurgery for a cerebral arteriovenous malformation (AVM). A tough capsule containing multiple layers of organized hematoma resulting from previous bleeding was confirmed surgically. Histological examination revealed that the capsule consisted of a dense collagenous outer layer and a granulomatous newly vascularized inner layer with marked fibrosis. Hemosiderin deposits were frequently observed in the inner layer, which suggested recurrent minor bleeding from fragile vessels in this layer. An AVM was found in the hematoma, which had degenerated as the result of radiosurgery. A cross-section of the abnormal vessels showed various stages of obliteration due to intimal hypertrophy. The clinical course, radiological features, and histological findings in this case were compatible with those of previously reported chronic encapsulated hematomas. A possible mechanism of hematoma formation and its expansion are discussed.
Vertebral artery stenting following percutaneous transluminal angioplasty
Authors: Storey Gayle S. , Marks Michael P. , Dake Michael , Norbash Alexander M. , Steinberg Gary K.
Published: June 2009

✓ The authors report initial results and follow up using stent placement to treat atherosclerotic stenosis in vertebral arteries. Three patients with severe atherosclerotic vascular disease underwent vertebral artery stent placement using a balloon expandable stent. Medical therapy (aspirin and warfarin) and conventional percutaneous angioplasty failed to resolve the disease and the patients developed symptomatic restenosis within 3 months of angioplasty. Two patients had symptoms of anterior circulation ischemia with carotid artery occlusions and reduced supply to the anterior circulation from the stenosed vertebral arteries. One patient had recurrent posterior circulation symptoms. Stents were successfully placed in all three, resulting in immediate reversal of stenosis and resolution of symptoms. Clinical follow-up study (mean 9 months) has shown no recurrent symptoms in the patient with posterior circulation symptoms, but the two patients with anterior circulation ischemia did develop recurrent symptoms. Angiographic follow up in these two patients at 3 months and 1 year, however, demonstrated continued patency of vertebral artery lumina. They underwent extracranial—intracranial bypass surgery to relieve their symptoms. This experience suggests stents can be placed without complication in the proximal vertebral arteries and may have an adjunctive role in the treatment of atherosclerotic cerebrovascular disease following unsuccessful angioplasty.
Epidemiological study of primary intracranial tumors: a regional survey in Kumamoto Prefecture in the southern part of Japan
Authors: Kuratsu Jun-Ichi , Ushio Yukitaka
Published: June 2009

✓ This survey consists of 1117 residents of Kumamoto Prefecture who were diagnosed with primary intracranial tumors between 1989 and 1994. Age, sex, tumor type, and date of diagnosis were recorded in all cases; 79% of the diagnoses were confirmed histologically. The overall age-adjusted incidence rate was 9.47 per 100,000 population per year. Among males, the age-adjusted incidence rate was 8.24 per 100,000 per year, and the breakdown included 2.36 gliomas, 1.56 meningiomas, 1.46 pituitary tumors, and 0.99 neurinomas. Among females, the comparable overall rate was 10.7; that included a rate of 3.95 for meningiomas, 2.04 for gliomas, 2.16 for pituitary tumors, and 0.75 for neurinomas. Meningiomas were the most common tumor, with an average annual age-adjusted incidence of 2.76 per 100,000 population. The highest incidence of meningiomas was 13.02 per 100,000 among women aged 70 to 79 years. The highest incidence of gliomas (5.71 per 100,000 males and 5.29 per 100,000 females) was seen in patients between 60 and 69 years of age. Meningiomas, pituitary adenomas, and malignant lymphomas occurred at a higher rate in females (male/female ratio: 0.39, 0.68, and 0.81, respectively). On the other hand, gliomas, neurinomas, and germ-cell tumors occurred more often in males (male/female ratio: 1.16, 1.32, and 4.29, respectively). Meningiomas and germ-cell tumors tended to exhibit gender specificity.
Distribution of substance P in the spinal cord of patients with syringomyelia
Authors: Milhorat Thomas H. , Mu Harrison T. M. , LaMotte Carole C. , Milhorat Ade T.
Published: June 2009

✓ The distribution of substance P, a putative neurotransmitter and pain-related peptide, was studied using the peroxidase—antiperoxidase immunohistochemical method in the spinal cords obtained from autopsy of 10 patients with syringomyelia and 10 age- and sex-matched, neurologically normal individuals. Substance P immunoreactivity was present in axons and in terminal-like processes in close apposition to neurons in the first, second, and third laminae of the dorsal horn. Smaller amounts of peroxidase-positive staining were found in the fifth lamina of the dorsal horn, the intermediolateral nucleus, the intermediomedial nucleus, and the ventral horn. In nine of 10 patients with syringomyelia, there was a substantial increase in substance P immunoreactivity in the first, second, third, and fifth laminae below the level of the lesion. A marked reduction or absence of staining was present in segments of the spinal cord occupied by the syrinx. Central cavities produced bilateral abnormalities, whereas eccentric cavities produced changes that were ipsilateral to the lesion. No alterations in staining were found in the spinal cord of an asymptomatic patient with a small central syrinx. The authors conclude that syringomyelia can be associated with abnormalities in spinal cord levels of substance P, which may affect the modulation and perception of pain.
Biomechanical evaluation of Caspar and Cervical Spine Locking Plate systems in a cadaveric model
Authors: Clausen John D. , Ryken Timothy C. , Traynelis Vincent C. , Sawin Paul D. , Dexter Franklin , Goel Vijay K.
Published: June 2009

✓ There exist two markedly different instrumentation systems for the anterior cervical spine: the Cervical Spine Locking Plate (CSLP) system, which uses unicortical screws with a locking hub mechanism for attachment, and the Caspar Trapezial Plate System, which is secured with unlocked bicortical screws. The biomechanical stability of these two systems was evaluated in a cadaveric model of complete C5–6 instability. The immediate stability was determined in six loading modalities: flexion, extension, right and left lateral bending, and right and left axial rotation. Biomechanical stability was reassessed following fatigue with 5000 cycles of flexion-extension, and finally, the spines were loaded in flexion until the instrumentation failed. The Caspar system stabilized significantly in flexion before (p < 0.05) but not after fatigue, and it stabilized significantly in extension before (p < 0.01) and after fatigue (p < 0.01). The CSLP system stabilized significantly in flexion before (p < 0.01) but not after fatigue, and it did not stabilize in extension before or after fatigue. The moment needed to produce failure in flexion did not differ substantially between the two plating systems. The discrepancy in the biomechanical stability of these two systems may be due to differences in bone screw fixation.
Cerebral venous malformation—arteriovenous malformation transition forms
Authors: Mullan Sean , Mojtahedi Saeid , Johnson Douglas L. , MacDonald R. Loch
Published: June 2009

✓ Three cases of cerebral venous malformation (CVM) are presented to demonstrate the triad that characterizes CVM: abnormal surface venous drainage, a “star-cluster” system of deep collecting veins, and a deep draining vein. Four other cases are introduced that illustrate this triad and show an additional feature, namely arterial fistulization; these cases represent arteriovenous malformations (AVMs). A final case demonstrates a CVM within an AVM. Both of these structures have a common draining vein and an identical venous core. On the basis of the cases described and of others less suitable for illustration, it is postulated that an AVM is a fistulized CVM and that both relate to a failure in the development of the cortical venous mantle. This proposition is based on the authors' observations and their assessment of the “best possible fit.”
Treatment of brain arteriovenous malformations by embolization and radiosurgery
Authors: Gobin Y. Pierre , Laurent Alexandre , Merienne Louis , Schlienger Maurice , Aymard Armand , Houdart Emmanuel , Casasco Alfredo , Lefkopoulos Dimitri , George Bernard , Merland Jean Jacques
Published: June 2009

✓ Embolization was used to reduce the size of brain arteriovenous malformations (AVMs) prior to radiosurgical treatment in 125 patients who were poor surgical candidates or had refused surgery. Of these patients, 81% had suffered hemorrhage, and 22.4% had undergone treatment at another institution. According to the Spetzler—Martin scale, the AVMs were Grade II in 9.6%, Grade III in 31.2%, Grade IV in 30.4%, and Grades V to VI in 28.8% of the cases. Most embolizations were performed using cyanoacrylate delivered by flow-guided microcatheters. Radiosurgery was performed using a linear accelerator in 62 patients treated by the authors, and 34 patients were treated at other institutions using various methods. Embolization produced total occlusion in 11.2% of AVMs and reduced 76% of AVMs enough to allow radiosurgery. Radiosurgery produced total occlusion in 65% of the partially embolized AVMs (79% when the residual nidus was < 2 cm in diameter). Embolizations resulted in a mortality rate of 1.6% and a morbidity rate of 12.8%. No complications were associated with radiosurgery. The hemorrhage rate for partially embolized AVMs was 3% per year. No patient with a completely occluded AVM experienced rehemorrhage. Angiographic follow-up review of AVMs embolized with cyanoacrylate demonstrated a 11.8% revascularization rate, occurring within 1 year. It is concluded that after partial embolization with cyanoacrylate, the risk of hemorrhage from the residual nidus is comparable to the natural history of AVMs and that the residual nidus can be irradiated with results almost as good as for a native AVM of the same size.
Frequency of intracranial hemorrhage as a presenting symptom and subtype analysis: a population-based study of intracranial vascular malformations in Olmsted County, Minnesota
Authors: Brown Robert D. , Wiebers David O. , Torner James C. , O'Fallon W. Michael
Published: June 2009

✓ The purpose of this study was to determine the symptoms at presentation and the incidence of intracranial hemorrhage (ICrH) caused by intracranial vascular malformations (IVMs) in a defined population. The authors used the Mayo Clinic medical records linkage system to detect all cases of IVM among residents of Olmsted County, Minnesota, during the period 1965 through 1992. Forty-eight IVMs were detected over the 27-year period. Twenty-nine of the 48 patients were symptomatic at presentation. The most common presenting symptom was ICrH, which was present in 20 patients, 69% of all symptomatic cases. Sixty-five percent of arteriovenous malformations (AVMs) presented with ICrH. The most common subtype of ICrH was intracerebral hemorrhage, which was found in nine of 20 patients; the second most common subtype was subarachnoid hemorrhage. The peak occurrence of hemorrhage was during the fifth decade of life. The age- and gender-adjusted occurrence of a first ICrH from an IVM among residents of Olmsted County, Minnesota was 0.82 per 100,000 person years (95% confidence interval 0.46–1.19). There was no increase in the detection of IVM-related ICrH throughout the study period. The 30-day mortality rate following ICrH was 17.6% for patients with an AVM and 25% for all patients with IVMs. This study provides unique data on symptoms at presentation and the incidence of ICrH and hemorrhage subtypes from IVMs on a population basis.
Predicting outcome in poor-grade patients with subarachnoid hemorrhage: a retrospective review of 159 aggressively managed cases
Authors: Le Roux Peter D. , Elliott J. Paul , Newell David W. , Grady M. Sean , Winn H. Richard
Published: June 2009

✓ To determine what factors predict outcome, the authors retrospectively reviewed the management of all 159 poor-grade patients admitted to Harborview Medical Center at the University of Washington who suffered aneurysmal subarachnoid hemorrhage between 1983 and 1993. Favorable outcome (assessed by the Glasgow Outcome Scale) occurred in 53.9% of Hunt and Hess Grade IV, and 24.1% of Grade V patients. Outcome was largely determined by the initial hemorrhage and subsequent development of intractable intracranial hypertension or cerebral infarction. Using multivariate analysis, the authors developed three models to predict outcome. It was found that predicting outcome based only on clinical and diagnostic criteria present at admission may have resulted in withholding treatment from 30% of the patients who subsequently experienced favorable outcomes. It is concluded that aggressive management including surgical aneurysm obliteration can benefit patients with poor neurological grades and should not be denied solely on the basis of the neurological condition on admission.
Outcome analysis of 85 patients undergoing the pi procedure for correction of sagittal synostosis
Authors: Boop Frederick A. , Chadduck William M. , Shewmake Kristopher , Teo Charles
Published: June 2009

✓ The authors present a retrospective review of their experience with 85 cases using the pi procedure to correct sagittal synostosis. A male preponderance of four to one was recognized in this group. Sixty-five infants underwent computerized tomography scanning of the head prior to surgery; these scans revealed unexpected intracranial pathology in 5% of cases. Surgical complications included three intraoperative dural lacerations. All children received blood transfusions with no complications.

Cosmetic outcomes were excellent in 53%, good in 43%, and poor in 4% of cases. One patient required reoperation. All poor outcomes were in infants who were younger than 8 weeks of age at the time of surgery and who underwent a “reverse pi” procedure. Most of the excellent outcomes occurred in infants who were between 3 and 6 months of age at the time of surgery.

Although more extensive than strip craniectomy, the pi procedure can be accomplished with minimal morbidity. In the authors' opinion, the pi procedure provides better immediate and long-term cosmetic results than synostectomy alone.
Management of childhood craniopharyngioma: can the morbidity of radical surgery be predicted?
Authors: De Vile Catherine J. , Grant David B. , Kendall Brian E. , Neville Brian G. R. , Stanhope Richard , Watkins Kate E. , Hayward Richard D.
Published: June 2009

✓ Seventy-five children treated for craniopharyngioma between 1973 and 1994 were studied to demonstrate which pre- and intraoperative factors were indicative of a poor outcome as defined by a quantitative assessment of morbidity. This involved a retrospective review of 65 patients and a prospective study of 10 patients focused on clinical details and cranial imaging and a follow-up “study assessment” of 66 survivors performed over the last 2 years. As part of the assessment, 63 patients underwent magnetic resonance imaging with a three-dimensional volume acquisition sequence 1.5 to 19.2 years after initial surgery. Predictors of high morbidity included severe hydrocephalus, intraoperative adverse events, and young age (≤ 5 years) at presentation. Predictors of increased hypothalamic morbidity included symptoms of hypothalamic disturbance already established at diagnosis, greater height (≥ 3.5 cm) of the tumor in the midline, and attempts to remove adherent tumor from the region of the hypothalamus at operation. Large tumor size, young age, and severe hydrocephalus were predictors of tumor recurrence, whereas complete tumor resection (as determined by postoperative neuroimaging) and radiotherapy given electively after subtotal excision were less likely to be associated with recurrent disease. Based on these findings, the authors propose an individualized, more flexible treatment approach whereby surgical strategies may be modified to provide long-term tumor control with the lowest morbidity.
Jugular bulb temperature: comparison with brain surface and core temperatures in neurosurgical patients during mild hypothermia
Authors: Crowder C. Michael , Tempelhoff René , Theard M. Angèle , Cheng Mary Ann , Todorov Alexandre , Dacey Ralph G.
Published: June 2009

✓ Blood temperature at the jugular bulb was monitored in 10 patients undergoing neurovascular procedures that used induced mild hypothermia, and its correlation with surface brain, core, and peripheral temperatures was determined. The study was motivated by the difficulty encountered in directly measuring global brain temperature and the poor correlations between various core and peripheral sites temperatures and brain temperature, particularly during deep hypothermia. Although not statistically significant, previous studies have suggested a trend toward higher brain temperatures. Temperatures from the jugular bulb (collected using a No. 5 French Swan—Ganz catheter) as well as from subdural, pulmonary artery, esophagus, tympanic membrane, and bladder sites were analyzed during three surgical conditions: prior to incision, with the dura open, and after closure of the dura. No complications related to placement of the jugular bulb catheter, induced hypothermia, or temperature monitoring were seen. The authors found that jugular bulb temperature was similar to pulmonary artery and esophageal temperatures; although prior to incision it tended to be higher than that found at the pulmonary artery, most commonly by 0.2°C. Surface brain temperature was cooler than all other temperatures (p < 0.05), except that of the tympanic membrane, and was particularly sensitive to environmental variations. Finally, as has been shown by others, bladder temperature lagged substantially behind core temperatures particularly during rapid cooling and rewarming of the patient. In summary, monitoring of jugular bulb temperature is a feasible technique, and temperatures measured in the jugular bulb are similar to core temperatures.
A use-dependent sodium channel antagonist, 619C89, in reduction of ischemic brain damage and glutamate release after acute subdural hematoma in the rat
Authors: Tsuchida Eiji , Harms John F. , Woodward John J. , Bullock Ross
Published: June 2009

✓ Acute subdural hematoma kills or disables more severely head injured patients than any other complication of cranial trauma. The main pathological factor involved is ischemic neuronal damage, which is caused by raised intracranial pressure and local effect. The authors have evaluated the hypothesis that a novel use-dependent sodium channel antagonist, 619C89, could reduce ischemic brain damage in the rat subdural hematoma model. Because previous studies have shown that focal neuronal damage may be mediated by “excitotoxic” mechanisms, and because excitatory amino acid levels have been shown to be markedly elevated after brain trauma in humans, the authors have measured levels of glutamate, aspartate, and threonine within the cortex underneath the hematoma, using in vivo microdialysis before and after induction of hematoma, in both vehicle- and drug-treated rats.

Postinjury treatment with 619C89 (30 mg/kg) significantly reduced the volume of hemispheric ischemic damage produced by subdural hematoma, from 99.77 ± 7.51 mm3in vehicle-treated control rats to 46.07 ± 11.06 mm3(p = 0.0007) in drug-treated animals. In the vehicle-treated animals, induction of subdural hematoma led to a fourfold increase in glutamate in the first 30 minutes after subdural hematoma occurred. The mean extracellular glutamate concentration in these animals remained 2- to 2.6-fold increased over the following 2.5 hours. In the 619C89-treated animals, the release of glutamate from the cortex underneath the hematoma was significantly attenuated. In these rats, induction of subdural hematoma led to a 2.7-fold increase in the first 30-minute sample, but extracellular glutamate concentration returned to near-basal levels thereafter, compared with vehicle-treated animals (p < 0.05). These results show that 619C89 is highly neuroprotective in this model and that its effects may, in part, be mediated by the inhibiton of glutamate release from the ischemic cortex underneath the hematoma.
Effect of magnesium given 1 hour after head trauma on brain edema and neurological outcome
Authors: Feldman Zeev , Gurevitch Boris , Artru Alan A. , Oppenheim Arieh , Shohami Esther , Reichenthal Eli , Shapira Yoram
Published: June 2009

✓ Excitatory amino acids (EAA), mainly glutamate and aspartate, are released in excessive amounts from terminals of ischemic or traumatically injured neurons. These excessive levels of EAAs initiate a cascade of events believed to lead to secondary delayed damage to the surrounding brain. The N-methyl-d-aspartate receptor antagonists MK-801 and ketamine are reported to suppress excessive EAA release and to attenuate the development of focal brain edema following neuronal injury. Magnesium is also reported to work at the postsynaptic receptor to reduce the neurotoxic effect of glutamate. The present study was undertaken to examine the effect of postinjury treatment with Mg++ on brain edema and neurological outcome after traumatic brain injury.

Sixty-nine rats that survived halothane anesthesia and closed head trauma (CHT) were randomly assigned to one of seven experimental groups: sham, CHT, and CHT with administration of Mg++ 1 hour postinjury. At 48 hours, brain tissue Mg++ concentration (calculated from optical density using a standard curve) was significantly increased compared to baseline levels (10.06 ± 2.44 mg/g vs. 6.83 ± 0.81 mg/g, p < 0.01 calculated by one-way analysis of variance). Also at 48 hours postinjury, brain tissue specific gravity in the contused hemisphere of Mg++-treated rats was significantly greater than that in the contused hemisphere of untreated rats, indicating attenuation of brain edema formation by Mg++. The neurological severity score (NSS) of rats treated with Mg++ improved significantly at both 18 and 48 hours, compared to baseline values obtained 1 hour after CHT but prior to administration of Mg++ (11.2 ± 2.5 vs. 15.2 ± 4.1, p = 0.03; and 12.3 ± 6.1 vs. 17.3 ± 3.6, p = 0.004, respectively). In the untreated groups, the NSS at 18 and 48 hours was not significantly different from baseline values (that is, no neurological improvement). The present study indicates that postinjury treatment with Mg++ attenuates brain edema formation and improves neurological outcome after experimental CHT.
Primitive neuroectodermal tumor of the median nerve Case report with cytogenetic analysis
Authors: Akeyson Edward W. , McCutcheon Ian E. , Pershouse Mark A. , Steck Peter A. , Fuller Gregory N.
Published: June 2009

✓ The authors describe a malignant peripheral primitive neuroectodermal tumor (PNET) that originated in the median nerve in an elderly adult. After the diagnosis was made by biopsy, the patient underwent radical local resection with interpositional vein grafting of the brachial artery. The tumor had the typical appearance of a primitive neural tumor with small, round cells forming rosettes. It stained positively for both the Ewing's sarcoma/peripheral PNET antigen (HBA-71) and neuron-specific enolase, confirming its neural origin. Ultrastructural examination revealed dense core granules and suggested neural differentiation of the neoplasm. Cytogenetic analysis suggested a chromosome (11;22) translocation typical of peripheral PNET. Early reports consisted of tumors arising solely in peripheral nerves, but recent series have focused mainly on tumors arising in the soft tissues other than nerves. There are no other cases of true PNET of peripheral nerve in the modern literature that have been fully characterized by immunohistochemical, ultrastructural, and cytogenetic criteria. Although peripheral PNETs occur more commonly in children, this unusual neoplasm should be considered in the differential diagnosis of peripheral nerve neoplasms in adults. Early diagnosis is desirable because of its aggressive nature and poor outcome.
Management and outcome of posttraumatic syringomyelia
Authors: Sgouros Spiros , Williams Bernard
Published: June 2009

✓ Traumatic paraplegia is the most common cause of nonhindbrain—related syringomyelia. Fifty-seven patients with a mean age of 34.3 years at presentation were treated at the Midland Centre for Neurosurgery and Neurology between 1973 and 1993. A variety of treatment strategies have been used over the years, including syringosubarachnoid and syringopleural shunts, spinal cord transection, and pedicled omental graft transposition. More recently decompressive laminectomy, subarachnoid space reconstruction and formation of surgical meningocele have been used. A total of 81 operations were performed in these patients, 69 of them at the Syringomyelia Clinic. Combinations of strategies were often chosen; the use of one strategy such as drainage did not preclude another such as transection or augmentation of the cerebrospinal fluid pathways.

The overall postoperative complication rate was 12%. Problems specific to the operation type included dislodged, blocked, and infected drains (10 patients). Acute gastric dilation was seen following pedicled omental graft (one patient). At 6 years only 49% of the drains inserted still functioned. A higher than expected rate of cervical spondylotic myelopathy has been noted. Two patients developed Charcot's joints. Thirty-six patients were asked to score themselves with regard to limb function and performance of daily living activities and 30% reported improvement, particularly in arm function.

Since the use of magnetic resonance imaging has become widespread, it has become apparent that decompressive laminectomy with subarachnoid space reconstruction is effective in controlling the syrinx cavity. In complete paraplegia, spinal cord transection is an effective alternative. Pedicled omental grafting was associated with poor outcome and an increased complication rate and has been abandoned.
Differentiation of receptive fields in the sensory cortex following stimulation of various nerves of the lower limb in humans: a magnetoencephalographic study
Authors: Shimojo Motoko , Kakigi Ryusuke , Hoshiyama Minoru , Koyama Sachiko , Kitamura Yoshihiro , Watanabe Shoko
Published: June 2009

✓ The authors investigated magnetoencephalography following stimulation of the posterior tibial (PT) and sural (SU) nerves at the ankle, the peroneal nerve (PE) at the knee, and the femoral nerve (FE) overlying the inguinal ligament in seven normal subjects (14 limbs) and confirmed its usefulness in clarifying the detailed differentiation of the receptive fields in the lower limb area of the primary sensory cortex in humans. The results were summarized as follows: 1) the equivalent current dipoles (ECDs) estimated by the magnetic fields following stimulation of the PT and SU were located very close to each other, along the interhemispheric fissure in all 14 limbs. They were directed horizontally to the hemisphere ipsilateral to the stimulated nerve. 2) The ECD following stimulation of the FE was clearly different from that seen in the other nerves, in terms of the location and/or direction, in all 14 limbs. The ECDs of 14 limbs were classified into two types according to the distance of ECD location between PT and FE; Type 1 (> 1 cm, nine limbs) and Type 2 (< 1 cm, five limbs). The ECD following FE stimulation was located on the crown of the postcentral gyrus or at the edge of the interhemispheric fissure in Type 1 and was close to the ECDs following PT and SU stimulation along the interhemispheric fissure in Type 2. 3) The ECD following PE stimulation was located along the interhemispheric fissure in all 14 limbs as for PT and SU. Its location was slightly but significantly higher than that of PT and SU in Type 1 and was close to ECDs following PT and SU stimulation in Type 2. The present findings indicated that approximately 65% (nine of 14) of the limbs showed the particular receptive fields compatible with the homunculus. Large inter- and the intraindividual (left—right) differences found in the present study indicated a significant anatomical variation in the area of the lower limb in the sensory cortex of humans.
Biomechanical characteristics of C1–2 cable fixations
Authors: Dickman Curtis A. , Crawford Neil R. , Paramore Christopher G.
Published: June 2009

✓ The biomechanical characteristics of four different methods of C1–2 cable fixation were studied to assess the effectiveness of each technique in restoring atlantoaxial stability. Biomechanical testing was performed on the upper cervical spines of four human cadaveric specimens. Physiological range loading was applied to the atlantoaxial specimens and three-dimensional motion was analyzed with stereophotogrammetry. The load–deformation relationships and kinematics were measured, including the stiffness, the angular ranges of motion, the linear ranges of motion, and the axes of rotation.

Specimens were nondestructively tested in the intact state, after surgical destabilization, and after each of four different methods of cable fixation. Cable fixation techniques included the interspinous technique, the Brooks technique, and two variants of the Gallie technique. All specimens were tested immediately after fixation and again after the specimen was fatigued with 6000 cycles of physiological range torsional loading.

All four cable fixation methods were moderately flexible immediately; the different cable fixations allowed between 5° and 40° of rotational motion and between 0.6 and 7 mm of translational motion to occur at C1–2. The Brooks and interspinous methods controlled C1–2 motion significantly better than both of the Gallie techniques. The motion allowed by one of the Gallie techniques did not differ significantly from the motion of the unfixed destabilized specimens. All cable fixation techniques loosened after cyclic loading and demonstrated significant increases in C1–2 rotational and translational motions. The bone grafts shifted during cyclic loading, which reduced the effectiveness of the fixation.

The locations of the axes of rotation, which were unconstrained and mobile in the destabilized specimens, became altered with cable fixation. The C1–2 cables constrained motion by shifting the axes of rotation so that C-1 rotated around the fixed cable and graft site. After the specimen was fatigued, the axes of rotation became more widely dispersed but were usually still localized near the cable and graft site.

Adequate healing requires satisfactory control of C1–2 motion. Therefore, some adjunctive fixation is advocated to supplement the control of motion after C1–2 cable fixation (that is, a cervical collar, a halo brace, or rigid internal fixation with transarticular screws).
Inhibition of cellular growth and induction of apoptosis in pituitary adenoma cell lines by the protein kinase C inhibitor hypericin: potential therapeutic application
Authors: Hamilton H. Bruce , Hinton David R. , Law Ronald E. , Gopalakrishna Rayudu , Su Yu Zhuang , Chen Zhen-Hai , Weiss Martin H. , Couldwell William T.
Published: June 2009

✓ Protein kinase C (PKC) is an enzyme involved in the regulation of cellular growth, proliferation, and differentiation in a number of tissues including the anterior pituitary, in which it is also believed to play a role in hormone secretion. Protein kinase C activity and expression have been found to be greater in adenomatous pituitary cells than in normal human and rat pituitary cells and higher in invasive pituitary tumor cells than in noninvasive ones. Inhibition of PKC activity has been shown in a variety of tumor cells to inhibit growth in a dose-related fashion. The purpose of the current study was to determine whether hypericin, a potent inhibitor of PKC activity that may be administered clinically, alters the growth and proliferation in established pituitary adenoma lines and to determine if inhibition of PKC activity induces apoptosis, as reported in some other tumor cell types. Two established pituitary adenoma cell lines, AtT-20 and GH4C1, were treated with hypericin in tissue culture for defined periods following passage. Inhibition of growth was found to be dose dependent in all three cell lines in low micromolar concentrations of hypericin, as determined by viable cell counts, methylthiotetrazole assay, and [3H]thymidine uptake studies. Concentrations of hypericin as low as 100 nM also induced apoptosis in these established lines, whereas treatment of normal human fibroblasts with a concentration of 10 µM failed to induce apoptosis. The potential use of hypericin in the therapy of pituitary adenomas warrants additional in vitro investigations with the aim of later moving toward therapeutic trials in selected patients in whom surgical or medical therapy has failed.