bluuebunny/crossref_metadata_2025 huggingface dataset:
Endovascular occlusion of a carotid pseudoaneurysm complicating deep neck space infection in a child
Authors: Reisner Andrew , Marshall Gary S. , Bryant Kristina , Postel Gregory C. , Eberly Steven M.
Published: May 2009

✓ Pseudoaneurysm formation of the cervical internal carotid artery (ICA) is a rare, potentially lethal complication of deep neck space infection. This entity typically occurs following otolaryngological or upper respiratory tract infection. The pseudoaneurysm is heralded by a pulsatile neck mass, Horner's syndrome, lower cranial neuropathies, and/or hemorrhage that may be massive. The recommended treatment includes prompt arterial ligation.

The authors present a case of pseudoaneurysm of the cervical ICA complicating a deep neck space infection. A parapharyngeal Staphylococcus aureus abscess developed in a previously healthy 6-year-old girl after she experienced pharyngitis. The abscess was drained via an intraoral approach. On postoperative Day 3, the patient developed a pulsatile neck mass, lethargy, ipsilateral Horner's syndrome, and hemoptysis, which resulted in hemorrhagic shock. Treatment included emergency endovascular occlusion of the cervical ICA and postembolization antibiotic treatment for 6 weeks. The patient has made an uneventful recovery as of her 18-month follow-up evaluation.

Conclusions drawn from this experience and a review of the literature include the following: 1) mycotic pseudoaneurysms of the carotid arteries have a typical clinical presentation that should enable timely recognition; 2) these lesions occur more commonly in children than in adults; 3) angiography with a view to performing endovascular occlusion should be undertaken promptly; and 4) endovascular occlusion of the pseudoaneurysm is a viable treatment option.
Prognostic value of early computerized tomography scanning following craniotomy for traumatic hematomas
Authors: Lubillo Santiago , Bolaños José , Carreira Luis , Cardeñosa José , Arroyo Javier , Manzano José
Published: May 2009

Object. Patients with head injuries traditionally were categorized on the basis of whether their lesions appeared to be diffuse, focal, or mass lesions on admission computerized tomography (CT) scanning. In the classification of Marshall, et al., the presence of a hematoma (evacuated or not evacuated) is more significant than any diffuse injury (DI). The CT scan appearance after evacuation of a mass lesion has not been analyzed previously in relation to outcome. The authors have investigated the importance of: 1) neurological assessment at hospital admission; 2) the status of the basal cisterns and associated intracranial lesions on the admission CT scan; and 3) the degree of DI on the early CT scan obtained after craniotomy to identify patients at risk for development of raised intracranial pressure (ICP) and lowered cerebral perfusion pressure (CPP) and to discover the influence of the postoperative CT appearance of the lesion on patient outcome.

Methods. The authors prospectively studied 82 patients with isolated, severe closed head injury (Glasgow Coma Scale [GCS] score ≤ 8), all of whom had intracranial hematoma. Both ICP and CPP were continuously monitored, and a CT scan was obtained within 2 to 12 hours after craniotomy. The CT images were categorized according to the classification of Marshall, et al.

The mortality rate during the hospital stay was 37%, and 50% of the patients achieved a favorable outcome. Compression of the basal cistern on the admission (preoperative) CT scan was associated with raised ICP and a CPP of less than 70 mm Hg but not with any other features or with poor patient outcome. In 53 patients the postoperative CT scan revealed DIs III or IV and 29 patients had DIs I or II. The percentages of time during the hospital stay in which ICP was higher than 20 mm Hg and CPP was lower than 70 mm Hg as well as unfavorable outcome were higher in the group of patients in whom DI III or IV was present (p < 0.001). Raised ICP, CPP lower than 70 mm Hg, DI III or IV, and unfavorable outcome were more frequently observed in patients who presented with a motor (m)GCS score of 3 or less, bilateral unreactive pupils, associated intracranial injuries, and hypotension (p < 0.001). When logistic regression analysis was performed, an mGCS score of 3 or less (p = 0.0013, odds ratio [OR] 10.8), bilateral unreactive pupils (p = 0.0047, OR 31.8), and DI III or IV observed on CT scanning after surgery (p = 0.015, OR 8.9) were independently associated with poor outcome.

Conclusions. Features on CT scans obtained shortly after craniotomy constitute an independent predictor of outcome in patients with traumatic hematoma. Patients in whom DI III or IV appears on postoperative CT scanning, who often present with an mGCS score of 3 or less and nonreactive pupils, are at high risk for the development of raised ICP and lowered CPP.
Comparative localization of auditory comprehension by using functional magnetic resonance imaging and cortical stimulation
Authors: Schlosser Michael J. , Luby Marie , Spencer Dennis D. , Awad Issam A. , McCarthy Gregory
Published: May 2009

Object. The authors previously described a functional magnetic resonance (fMR) imaging task for the localization of auditory comprehension in which focal activation of posterior temporal and inferior frontal regions of the left hemisphere was reliably demonstrated. Because this study was conducted in neurologically normal volunteers, it was not possible to determine whether the activated regions were critical to the performance of language tasks; that is, whether the fMR imaging activations provided a valid measure of language processing. A direct comparison of fMR imaging language activation with cortical stimulation must be completed before it can be used with confidence in presurgical planning, and this comparison is performed in the present study.

Methods. The authors report on a series of 33 consecutive patients who underwent dominant hemisphere resection and in whom fMR imaging mapping of auditory comprehension was performed at the Yale neurosurgical program.

In 23 of the 33 patients fMR imaging activation was consistent with the typical results obtained in normal participants in the earlier study. In 16 of these 23 patients language mapping was performed using either intra- or extraoperative cortical stimulation. Cortical stimulation failed to localize language areas in two of the 16 patients. Electrical stimulation that was performed in proximity to the fMR image activations interfered with auditory comprehension, object naming, or speech production in 12 of the remaining 14 patients. Five of the 10 cases in which evocation of reliable fMR imaging activation failed were attributable to technical problems and/or patient head movement.

Conclusions. Cortical stimulation results and fMR imaging findings were consistent in all but two patients. However, the spatial extent of the activation produced by fMR imaging and the spatial extent of stimulation-induced language disruption that was caused by direct cortical stimulation did not always correspond. Problems in defining the extent of activation by both methods are discussed.
Exacerbation of cortical and hippocampal CA1 damage due to posttraumatic hypoxia following moderate fluid-percussion brain injury in rats
Authors: Bramlett Helen M. , Green Edward J. , Dietrich W. Dalton
Published: May 2009

Object. Patients with head injuries often experience respiratory distress that results in a secondary hypoxic insult. The present experiment was designed to assess the histopathological consequences of a secondary hypoxic insult by using an established rodent model of traumatic brain injury (TBI).

Methods. Intubated anesthetized rats were subjected to moderate (1.94–2.18 atm) parasagittal fluid-percussion injury (FPI) to the brain. Following the TBI, the animals were maintained for 30 minutes by using either hypoxic (TBI-HY group, nine animals) or normoxic (TBI-NO, 10 animals) gas levels. Sham-operated animals also underwent all manipulations except for the FPI (sham-HY group, seven animals; and sham-NO group, seven animals). Three days after TBI the rats were killed, and quantitative histopathological evaluation was undertaken. Cortical contusion volumes were dramatically increased in the TBI-HY group compared with the TBI-NO group (p < 0.03). Qualitative assessment of cortical and subcortical structures demonstrated significant damage within the hippocampal areas, CA1 and CA2, of TBI-HY animals compared with the TBI-NO animals (both p < 0.03). There was also a significant increase in the frequency of damaged neuronal profiles within the middle and medial sectors of the CA1 hippocampus (p < 0.03) due to the hypoxic insult.

Conclusions. The results of this study demonstrate that a secondary hypoxic insult following parasagittal FPI exacerbates contusion and neuronal pathological conditions. These findings emphasize the need to control for secondary hypoxic insults after experimental and human head injury.
Expanding lacunae causing triventricular hydrocephalus
Authors: Mascalchi Mario , Salvi Fabrizio , Godano Umberto , Nistri Marco , Taiuti Rosanna , Tosetti Michela , Villari Natale , Calbucci Fabio
Published: May 2009

✓ Two patients are reported in whom the presence of triventricular hydrocephalus and aqueductal obstruction or stenosis due to multiple expanding lacunae in the mesencephalothalamic region possibly corresponds to abnormally dilated perivascular spaces. Placement of a ventriculoperitoneal cerebrospinal fluid (CSF) shunt in one patient and the performance of a third ventricle cisternotomy in the other reversed the hydrocephalic syndrome, but did not modify the complex neuroophthalmological disturbance and rubral tremor presumably related to the compressive effects of the lacunae on adjacent parenchyma. In one patient the number and size of the lacunae were increased 4 years after CSF shunt placement. A review of the literature revealed two cases in which magnetic resonance imaging demonstrated a similar, poorly understood pathological condition.
Cerebral microdialysis combined with single-neuron and electroencephalographic recording in neurosurgical patients
Authors: Fried Itzhak , Wilson Charles L. , Maidment Nigel T. , Engel Jerome , Behnke Eric , Fields Tony A. , Macdonald Katherine A. , Morrow Jack W. , Ackerson Larry
Published: May 2009

✓ Monitoring physiological changes in the brain parenchyma has important applications in the care of neurosurgical patients. A technique is described for measuring extracellular neurochemicals by cerebral microdialysis with simultaneous recording of electroencephalographic (EEG) and single-unit (neuron) activity in selected targets in the human brain. Forty-two patients with medically intractable epilepsy underwent stereotactically guided implantation of a total of 423 intracranial depth electrodes to delineate potentially resectable seizure foci. The electrodes had platinum alloy contacts for EEG recordings and four to nine 40-µm microwires for recording single-unit neuron activity. Eighty-six electrodes also included microdialysis probes introduced via the electrode lumens. During monitoring on the neurosurgical ward, electrophysiological recording and cerebral microdialysis sampling were performed during seizures, cognitive tasks, and sleep—waking cycles. The technique described here could be used in developing novel approaches for evaluation and treatment in a variety of neurological conditions such as head injury, subarachnoid hemorrhage, epilepsy, and movement disorders.
The impact of raised intracranial pressure on cerebral venous hemodynamics: a prospective venous transcranial Doppler ultrasonography study
Authors: Schoser Benedikt G. H. , Riemenschneider Nils , Hansen H. Christian
Published: May 2009

Object. The effect of increased intracranial pressure (ICP) on cerebral venous blood flow has been the subject of very few clinical and experimental studies. The authors assessed the usefulness of venous transcranial Doppler (TCD) ultrasonography as a noninvasive monitoring tool for predicting raised ICP.

Methods. Serial venous TCD studies of the basal vein of Rosenthal and the straight sinus (SS) were prospectively performed in 30 control volunteers and 25 patients with raised ICP. Correlations with ICP data were calculated using a multivariate regression model. Venous blood flow velocities (BFVs) in the basal vein of Rosenthal showed, within a certain range, a linear relationship between mean ICP and maximal venous BFV (r = 0.645; p < 0.002). Moreover, a linear relationship was found for maximal venous BFVs in the SS and mean ICP (r = 0.928; p < 0.0003).

Conclusions. Venous TCD studies may provide an additional noninvasive monitoring tool for raised ICP and give further insights into the cerebral venous hemodynamics present during raised ICP.
Computerized tomography angiography in patients with subarachnoid hemorrhage: from aneurysm detection to treatment without conventional angiography
Authors: Velthuis Birgitta K. , van Leeuwen Maarten S. , Witkamp Theodoor D. , Ramos Lino M. P. , van der Sprenkel Jan Willem Berkelbach , Rinkel Gabriël J. E.
Published: May 2009

Object. The purpose of this study was to determine prospectively whether and to what extent computerized tomography (CT) angiography can serve as the sole imaging method for a preoperative workup in patients with ruptured intracranial aneurysms.

Methods. During a 1-year period, all patients who presented to the authors' hospital with subarachnoid hemorrhage demonstrated by unenhanced CT scanning or lumbar puncture underwent CT angiography. Two radiologists evaluated the CT angiography source images and maximum intensity projection slabs and arrived at a consensus. They categorized the quality of the CT angiography as adequate or inadequate and classified aneurysms that were detected as definitely or possibly present. The parent artery of anterior communicating artery aneurysms was identified by asymmetrical anterior cerebral artery size and asymmetrical aneurysm location. The parent artery was indicated by the larger A1 segment in cases of asymmetrical A1 size. Only CT angiograms of adequate quality that revealed aneurysms classified as definitely present and with an unequivocal parent artery were presented to the neurosurgeons, who decided whether preoperative digital subtraction (DS) angiography should still be performed.

Forty-nine of the 100 studied patients did not undergo surgery because of poor clinical condition, nonaneurysmal cause of the hemorrhage, or endovascular treatment of the ruptured aneurysm. Of the 51 patients who underwent surgery, radiologists required DS angiography in 17 patients; the imaging technique provided greater certainty in 13 instances. The neurosurgeons required DS angiography 11 times; this provided additional information in two instances. Twenty-three (45%) of the 51 patients were surgically treated successfully on the basis of CT angiography findings alone.

Conclusions. Computerized tomography angiography can replace DS angiography as the preoperative neuroimaging technique in a substantial proportion of patients with ruptured intracranial aneurysms.
Localization of language-specific cortex by using magnetic source imaging and electrical stimulation mapping
Authors: Simos Panagiotis G. , Papanicolaou Andrew C. , Breier Joshua I. , Wheless James W. , Constantinou Jules E. C. , Gormley William B. , Maggio William W.
Published: May 2009

Object. In this paper the authors demonstrate the concordance between magnetic source (MS) imaging and direct cortical stimulation for mapping receptive language cortex.

Methods. In 13 consecutive surgical patients, cortex specialized for receptive language functions was identified noninvasively by obtaining activation maps aided by MS imaging in the context of visual and auditory word-recognition tasks. Surgery was then performed for treatment of medically intractable seizure disorder (eight patients), and for resection of tumor (four), or angioma (one). Mapping of language areas with cortical stimulation was performed intraoperatively in 10 patients and extraoperatively in three. Cortical stimulation mapping verified the accuracy of the MS imaging—based localization in all cases.

Conclusions. Information provided by MS imaging can be especially helpful in cases of atypical language representation, including bihemispheric representation, and location of language in areas other than those expected within the dominant hemisphere, such as the anterior portion of the superior temporal gyrus, the posteroinferior portion of the middle temporal gyrus, the basal temporal cortex, and the lateral temporooccipital cortex.
Sagittal sinus occlusion by intraluminal dural cysts
Authors: Ojemann Jeffrey G. , Moran Christopher J. , Gokden Murat , Dacey Ralph G.
Published: May 2009

✓ Lesions involving the sagittal sinus typically present as masses compressing the sinus externally. The authors describe two cases of lesions entirely within the lumen of the sagittal sinus. In one of the cases, syncope was the presenting symptom and surgical resection of the cyst was performed. An entirely intraluminal cyst, consistent with a dural cyst, was resected, followed by reconstruction of the sinus and resolution of symptoms. Entirely intraluminal lesions of the sagittal sinus have rarely been reported as incidental findings. This represents the first report of symptomatic occlusion of a venous sinus by an intraluminal cyst.
Iatrogenic pneumocephalus secondary to intravenous catheterization
Authors: Thompson Todd P. , Levy Elad , Kanal Emanuel , Lunsford L. Dade
Published: May 2009

✓ The presence of pneumocephalus in a patient without a history of undergoing intracranial or intrathecal procedures is a significant radiographic finding that portends a violation of the dural barrier or the presence of infection. The authors report a case of iatrogenic pneumocephalus that confounded the evaluation of a patient with unrelated neurological disorders, resulting in unnecessary transfer of the patient and utilization of medical resources. A review of 100 sequential computerized tomography scans obtained in patients for any indication in the emergency department revealed a 6% incidence of iatrogenic intravenous pneumocephalus. Computerized tomography scans revealing pneumocephalus had been obtained for altered mental status, focal motor deficit, seizure, and trauma. More careful intravenous catheterization and recognition of the condition on imaging may avoid similar problems.
A prospective comparison between three-dimensional magnetic resonance imaging and ventriculography for target-coordinate determination in frame-based functional stereotactic neurosurgery
Authors: Schuurman P. Richard , Bie Rob M. A. de , Majoie Charles B. L. , Speelman Johannes D. , Bosch D. Andries
Published: May 2009

Object. The purpose of this prospective study was to compare stereotactic coordinates obtained with ventriculography with coordinates derived from stereotactic computer-reconstructed three-dimensional magnetic resonance (3D-MR) imaging in functional stereotactic procedures.

Methods. In 15 consecutive patients undergoing functional stereotactic procedures, both preoperative frame-based stereotactic 3D-MR imaging and intraoperative ventriculography were performed. Differences between 3D-MR imaging and ventriculography in X, Y, and Z coordinates of the anterior commissure (AC), posterior commissure (PC), and target area were calculated, as well as the 3D distance between the position of AC, PC, and target within stereotactic space as obtained using both methods. The position of the stereotactic MR imaging fiducial markers measured using 3D-MR imaging compared well with the markers' known position embedded in the software (mean error 0.4 mm, maximal error for an individual slice 1.2 mm). For the individual coordinates, only for Y-PC was a difference found between 3D-MR imaging and ventriculography that significantly exceeded half the size of a pixel, the theoretical limit of precision when using a digitized imaging technique. However, the mean difference was smaller than 1 mm. The mean 3D distance between the 3D-MR imaging— and ventriculography-derived coordinates was 1.09 mm for AC, 1.13 mm for PC, and 1.29 mm for the targets.

Conclusions. With these data it is shown that there is sufficient agreement between ventriculography-derived and 3D-MR imaging—derived stereotactic coordinates to justify the use of 3D-MR imaging target determination in frame-based functional stereotactic neurosurgery.
Presurgical motor and somatosensory cortex mapping with functional magnetic resonance imaging and positron emission tomography
Authors: Bittar Richard G. , Olivier André , Sadikot Abbas F. , Andermann Frederick , Pike G. Bruce , Reutens David C.
Published: May 2009

Object. Accurate identification of eloquent cortex is important to ensure that resective surgery in the region surrounding the central sulcus is performed with minimum risk of permanent neurological deficit. Functional localization has traditionally been accomplished using intraoperative cortical stimulation (ICS). However, this technique suffers from several disadvantages that make the development and validation of noninvasive methods desirable. Functional localization accomplished by activation studies in which positron emission tomography (PET) scanning and the tracer [15O]H2O have been used has been shown to correlate well with the results of ICS. Another noninvasive method for functional localization is functional magnetic resonance (fMR) imaging. We compared the locations of activation peaks obtained in individual patients using fMR and [15O]H2O PET imaging.

Methods. Twenty-six combined PET activation—fMR imaging studies were performed in 11 patients who were admitted for evaluation before undergoing surgery in the region surrounding the central sulcus. The PET scans were obtained using bolus injections of the cerebral blood flow tracer [15O]H2O (10 mCi). Multislice T2*-weighted gradient-echo echoplanar images were acquired using a 1.5-tesla MR imaging system. Activation maps were aligned with anatomical MR images and transformed into stereotactic space, after which the locations of activation peaks obtained using both modalities were compared. The average distance between activation peaks obtained using fMR imaging and those obtained using PET imaging was 7.9 ± 4.8 mm (p > 0.05), with 96% of the peaks being located on either the same or adjacent sulci and gyri. Overlapping of voxels activated by each modality occurred in 92% of the studies. Functional MR imaging failed to activate the primary sensorimotor cortex in one study and produced results that were ambiguous in the clinical setting in three cases.

Conclusions. Overall, fMR imaging produced activation that correlated well with that obtained using PET scanning. Discrepancies between the sites of activation identified using these two techniques may reflect differences in their physiological bases.
Characterization of a model of hydrocephalus in transgenic mice
Authors: Cohen Alan R. , Leifer David W. , Zechel Marc , Flaningan Daniel P. , Lewin Jonathan S. , Lust W. David
Published: May 2009

Object. The purpose of this study was to elucidate the pathophysiological characteristics of hydrocephalus in a new transgenic model of mice created to overproduce the cytokine transforming growth factor—β1 (TGFβ1) in the central nervous system (CNS).

Methods. Galbreath and colleagues generated transgenic mice that overexpressed TGFβ1 in the CNS in an effort to examine the role of this cytokine in the response of astrocytes to injury. Unexpectedly, the animals developed severe hydrocephalus and died. The authors have perpetuated this transgenic colony to serve as a model of congenital hydrocephalus, breeding asymptomatic carrier males that are heterozygous for the transgene with wild-type females.

One hundred twelve (49.6%) of 226 mice developed clinical manifestations of hydrocephalus, characterized by dorsal doming of the calvaria, spasticity, limb tremors, ataxia, and, ultimately, death. The presence of the TGFβ1 transgene was determined by performing polymerase chain reaction (PCR) analysis of sample tail slices. Animals with the hydrocephalic phenotype consistently carried the transgene, although some animals with the transgene did not develop hydrocephalus. Animals without the transgene did not develop hydrocephalus.

Alterations in brain structure were characterized using magnetic resonance (MR) imaging, gross and light microscopic analysis, and immunocytochemical studies. Magnetic resonance imaging readily distinguished hydrocephalic animals from nonhydrocephalic controls and demonstrated an obstruction at the outlets of the fourth ventricle. Gross and light microscopic examination confirmed the MR findings. The results of immunofluorescent staining of brain tissue slices revealed the presence of the TGFβ1 cytokine and its receptor preferentially in the meninges and subarachnoid space in both hydrocephalic and control mice. Reverse transcriptase—PCR analysis demonstrated tissue-specific expression of the TGFβ1 gene in the brains of transgenic mice, and enzyme-linked immunosorbent assay confirmed overexpression of the TGFβ1 cytokine in brain, cerebrospinal fluid, and plasma.

Conclusions. The transgenic murine model provides a reproducible representation of congenital hydrocephalus. The authors hypothesize that overexpression of TGFβ1 in the CNS causes hydrocephalus by altering the environment of the extracellular matrix and interfering with the circulation of cerebrospinal fluid. A model of hydrocephalus in which the genetic basis is known should be useful for evaluating hypotheses regarding the pathogenesis of this disorder and should also help in the search for new treatment strategies.
Early alterations in cerebral hemodynamics, brain metabolism, and blood-brain barrier permeability in experimental intracerebral hemorrhage
Authors: Lee E-Jian , Hung Yu-Chang , Lee Ming-Yang
Published: May 2009

Object. The authors sought to ascertain the nature of the hemodynamic and metabolic derangement underlying acute pathophysiological events that occur after intracerebral hemorrhage (ICH).

Methods. Cerebral perfusion pressure (CPP), flow velocity (FV) of the middle cerebral artery, and the arteriovenous contents of oxygen and lactate were investigated in 24 dogs subjected to sham operations (Group A, four animals) or intracerebral injections of 3 ml (Group B, 11 animals) or 5 ml (Group C, nine animals) autologous arterial blood. Twelve additional dogs received intravenous injections of 2% Evans blue or trypan blue dye to evaluate blood-brain barrier (BBB) changes. Within 1 hour, animals with ICH exhibited a rise in FV associated with significant reductions (p < 0.05) in CPP and the arteriovenous content difference (AVDO2). In Group C animals significant increases in lactate concentration were found in arterial and superior sagittal sinus (SSS) samples compared with those in the other two groups (p < 0.05). Additionally, perihematomal dye extravasation was observed in animals subjected to ICH and trypan blue dye injections, with profound and mild leakages in Group C and Group B animals, respectively, but not in Group A and Evans blue dye—injected animals. During the subsequent 4 hours, the FV and AVDO2 returned to normal in Group B animals, indicating a balanced cerebral metabolic rate for oxygen (CMRO2) compared with a deranged CMRO2 in Group C animals due to their lowered FV and AVDO2. However, no coupling increase in brain lactate clearance in Group C animals accounted for either the early lactate elevation in SSS or the decrease in CMRO2.

Conclusions. Profound reductions in CPP and brain oxygenation after ICH may rapidly exhaust hemodynamic compensation and, thus, impede cerebral homeostasis; however, these reductions only modestly enhance anaerobic glycolysis. Furthermore, the data suggest that a selective increase in permeability, rather than anatomical disruption, of the BBB is involved in the acute pathophysiological events that occur after ICH, which may provide a possible gateway for systemic arterial lactate entering the SSS.
Quantitative assessment of vessel flow integrity for aneurysm surgery
Authors: Charbel Fady T. , Gonzales-Portillo Gabriel , Hoffman William E. , Ostergren Lauren A. , Misra Mukesh
Published: May 2009

✓ Quantitative measurement of blood flow in cerebral vessels during aneurysm surgery can help prevent ischemic injury and improve patient outcome. The authors report a case of a superior cerebellar artery (SCA) aneurysm in which perivascular microflow probes were used to measure blood flow quantitatively in both the SCA and the posterior cerebral artery before and after aneurysm clipping. Following aneurysm clipping, blood flow in the SCA was reduced to less than 25% of its initial baseline value. Prompt detection of compromised blood flow gave the surgeon the opportunity to adjust the clip and restore SCA flow to its preclipping value within 5 minutes of initial clip placement. Quantitative vessel-flow measurements were integral to the safe progression of the operation and may have prevented an adverse neurological outcome in this patient. The recommended surgical technique and the principle of operation are described.
Size-adjustable titanium plate for reconstruction of the sella turcica
Authors: Arita Kazunori , Kurisu Kaoru , Tominaga Atsushi , Ikawa Fusao , Iida Koji , Hama Selji , Watanabe Haruyuki
Published: May 2009

✓ A size-adjustable plate constructed of pure titanium is proposed for use in the reconstruction of the sella turcica. The plate is composed of two semicircular pieces that are connected by a hinge located at the top of the plate. Using an applicator, the plate is inserted into the sella turcica in a closed position. The same applicator is then used to open and secure the plate. The titanium causes minimal ferromagnetic artifacts on postoperative magnetic resonance imaging.

Preliminary findings indicate a possibie clinical use for this plate in the reconstruction of the sella turcica when no suitable piece of bone is available.
Endoscopic management of cysticercal cysts within the lateral and third ventricles
Authors: Bergsneider Marvin , Holly Langston T. , Lee Jae Hong , King Wesley A. , Frazee John G.
Published: May 2009

Object. In this report the authors review their 3-year experience with the endoscopic management of patients with hydrocephalus who harbored cysticercal cysts within the third and lateral ventricles. The management plan was to utilize an endoscopic approach to remove the cysts and to incorporate techniques useful in treating obstructive hydrocephalus. The ultimate goals were to avoid having to place a complication-prone cerebrospinal fluid shunt and to eliminate the risk of complications related to cyst degeneration.

Methods. A retrospective analysis of 10 patients with hydrocephalus and cysticercal cysts within the third or lateral ventricles who were endoscopically managed was performed. A general description of the instrumentation and technique used for removal of the intraventricular cysts is given. At presentation, neuroimaging revealed findings suggestive of obstructive hydrocephalus in eight patients.

Seven of the 10 patients treated endoscopically were spared the necessity of shunt placement. Three successful third ventriculostomies and one therapeutic septum pellucidotomy were performed. Despite frequent rupture of the cyst walls during removal of the cysts, there were no cases of ventriculitis. The endoscopic approach allowed successful removal of a cyst situated in the roof of the anterior third ventricle. One patient suffered from recurrent shunt obstructions secondary to a shunt-induced migration of cysts from the posterior fossa to the lateral ventricles.

Conclusions. The endoscopic removal of third and lateral ventricle cysticercal cysts, combined with a third ventriculostomy or septum pellucidotomy in selected cases, is an effective treatment in patients with hydrocephalus and should be considered the primary treatment for this condition.
Magnetic source imaging and brain surgery: presurgical and intraoperative planning in 26 patients
Authors: Alberstone Cary D. , Skirboll Stephen L. , Benzel Edward C. , Sanders John A. , Hart Blaine L. , Baldwin Nevan G. , Tessman Charles L. , Davis John T. , Lee Roland R.
Published: May 2009

Object. The availability of large-array biomagnetometers has led to advances in magnetoencephalography that permit scientists and clinicians to map selected brain functions onto magnetic resonance images. This merging of technologies is termed magnetic source (MS) imaging. The present study was undertaken to assess the role of MS imaging for the guidance of presurgical planning and intraoperative neurosurgical technique used in patients with intracranial mass lesions.

Methods. Twenty-six patients with intracranial mass lesions underwent a medical evaluation consisting of MS imaging, a clinical history, a neurological examination, and assessment with the Karnofsky Performance Scale. Magnetic source imaging was used to locate the somatosensory cortex in 25 patients, the visual cortex in six, and the auditory cortex in four. The distance between the lesion and the functional cortex was determined for each patient.

Twenty-one patients underwent a neurosurgical procedure. As a surgical adjunct, a frameless stereotactic navigational system was used in 17 cases and a standard stereotactic apparatus in four cases. Because of the results of their MS imaging examination, two patients were not offered surgery, four underwent a stereotactic biopsy procedure, 10 were treated with a subtotal surgical resection, and seven were treated with complete surgical resection. One patient deteriorated before a procedure could be scheduled and, therefore, was not offered surgery, and two patients were offered surgery but declined. Three patients experienced surgery-related complications.

Conclusions. Magnetic source imaging is an important noninvasive neurodiagnostic tool that provides critical information regarding the spatial relationship of a brain lesion to functional cortex. By providing this information, MS imaging facilitates a minimum-risk management strategy and helps guide operative neurosurgical technique in patients with intracranial mass lesions.
Increased cerebral blood flow but no reversal or prevention of vasospasm in response to l-arginine infusion after subarachnoid hemorrhage
Authors: Pluta Ryszard M. , Afshar John K. B. , Thompson B. Gregory , Boock Robert J. , Harvey-White Judith , Oldfield Edward H.
Published: May 2009

Object. The reduction in the level of nitric oxide (NO) is a purported mechanism of delayed vasospasm after subarachnoid hemorrhage (SAH). Evidence in support of a causative role for NO includes the disappearance of nitric oxide synthase (NOS) from the adventitia of vessels in spasm, the destruction of NO by hemoglobin released from the clot into the subarachnoid space, and reversal of vasospasm by intracarotid NO. The authors sought to establish whether administration of l-arginine, the substrate of the NO-producing enzyme NOS, would reverse and/or prevent vasospasm in a primate model of SAH.

Methods. The study was composed of two sets of experiments: one in which l-arginine was infused over a brief period into the carotid artery of monkeys with vasospasm, and the other in which l-arginine was intravenously infused into monkeys over a longer period of time starting at onset of SAH. In the short-term infusion experiment, the effect of a 3-minute intracarotid infusion of l-arginine (intracarotid concentration 10−6 M) on the degree of vasospasm of the right middle cerebral artery (MCA) and on regional cerebral blood flow (rCBF) was examined in five cynomolgus monkeys. In the long-term infusion experiment, the effect of a 14-day intravenous infusion of saline (control group, five animals) or l-arginine (10−3 M; six animals) on the occurrence and degree of cerebral vasospasm was examined in monkeys. The degree of vasospasm in all experiments was assessed by cerebral arteriography, which was performed preoperatively and on postoperative Days 7 (short and long-term infusion experiments) and 14 (long-term infusion experiment). In the long-term infusion experiment, plasma levels of l-arginine were measured at these times in the monkeys to confirm l-arginine availability.

Vasospasm was not affected by the intracarotid infusion of l-arginine (shown by the reduction in the right MCA area on an anteroposterior arteriogram compared with preoperative values). However, intracarotid l-arginine infusion increased rCBF by 21% (p < 0.015; PCO2 38–42 mm Hg) in all vasospastic monkeys compared with rCBF measured during the saline infusions. In the long-term infusion experiment, vasospasm of the right MCA occurred with similar intensity with or without continuous intravenous administration of l-arginine on Day 7 and had resolved by Day 14. The mean plasma l-arginine level increased during infusion from 12.7 ± 4 µg/ml on Day 0 to 21.9 ± 13.1 µg/ml on Day 7 and was 18.5 ± 3.1 µg/ml on Day 14 (p < 0.05).

Conclusions. Brief intracarotid and continuous intravenous infusion of l-arginine did not influence the incidence or degree of cerebral vasospasm. After SAH, intracarotid infusion of l-arginine markedly increased rCBF in a primate model of SAH. These findings discourage the use of l-arginine as a treatment for vasospasm after SAH.
Retrosigmoid intradural suprameatal approach to Meckel's cave and the middle fossa: surgical technique and outcome
Authors: Samii Madjid , Tatagiba Marcos , Carvalho Gustavo A.
Published: May 2009

Object. The goal of this study was to determine whether some petroclival tumors can be safely and efficiently treated using a modified retrosigmoid petrosal approach that is called the retrosigmoid intradural suprameatal approach (RISA).

Methods. The RISA was introduced in 1983, and since that time 12 patients harboring petroclival meningiomas have been treated using this technique. The RISA includes a retrosigmoid craniotomy and drilling of the suprameatus petrous bone, which is located above and anterior to the internal auditory meatus, thus providing access to Meckel's cave and the middle fossa.

Radical tumor resection (Simpson Grade I or II) was achieved in nine (75%) of the 12 patients. Two patients underwent subtotal resection (Simpson Grade III), and one patient underwent complete resection of tumor at the posterior fossa with subtotal resection at the middle fossa. There were no deaths or severe complications in this series; all patients did well postoperatively, being independent at the time of their last follow-up examinations (mean 5.6 years). Neurological deficits included facial paresis in one patient and worsening of hearing in two patients.

Conclusions. Theapproach described here is a useful modification of the retrosigmoid approach, which allows resection of large petroclival tumors without the need for supratentorial craniotomies. Although technically meticulous, this approach is not time-consuming; it is safe and can produce good results. This is the first report on the use of this approach for petroclival meningiomas.
Phase II evaluation of interferon α-2a for progressive or recurrent craniopharyngiomas
Authors: Jakacki Regina I. , Cohen Bruce H. , Jamison Cheryl , Mathews Vincent P. , Arenson Edward , Longee Darryl C. , Hilden Joanne , Cornelius Al , Needle Michael , Heilman Doug , Boaz Joel C. , Luerssen Thomas G.
Published: May 2009

Object. Craniopharyngiomas originate from the same cells as squamous cell skin carcinoma, which can be treated successfully with interferon-α (IFNα)-2a. The authors evaluated the activity and toxicity of systemic IFN in young patients with craniopharyngiomas.

Methods. Fifteen patients between the ages of 4.2 and 19.8 years who had progressive or recurrent craniopharyngiomas were enrolled in this study. Nine of these patients had never received external-beam radiation therapy. Therapy consisted of 8,000,000 U/m2 IFNα-2a administered daily for 16 weeks (induction phase) followed by the same dose three times per week for an additional 32 weeks (maintenance phase). Of the 12 patients who could be evaluated, radiological studies demonstrated a response to treatment in three with predominantly cystic tumors (one minor response, one partial response, and one complete response); one of these patients also showed improvement in visual fields. The size of the cystic component of the tumors often increased temporarily during the first several months of therapy. Three patients met the criteria for progressive disease during therapy. The median time to progression was 25 months. The need for radiation therapy in patients treated with IFN was delayed for 18 to 35 months (median 25 months) in six patients. All patients developed transient flulike symptoms shortly after receiving the first dose of IFN. Other toxicities (predominantly hepatic, neurological, and cutaneous) were seen in nine (60%) of the 15 patients during the first 8 weeks of treatment but resolved after temporary discontinuation and/or dose reduction.

Conclusions. Interferon-α-2a is active against some childhood craniopharyngiomas; its toxicity precludes administration of high daily doses, and the optimum dose level and schedule remain to be defined.
Primary intracerebral malignant lymphoma: report of 248 cases
Authors: Bataille Benoit , Delwail Vincent , Menet Emmanuelle , Vandermarcq Pierre , Ingrand Pierre , Wager Michel , Guy Gilles , Lapierre Francoise
Published: May 2009

Object. The authors present a retrospective analysis of 248 immunocompetent patients with primary intracerebral lymphoma treated at 19 French and Belgian medical centers between January 1980 and December 1995.

Methods. This study involved 127 female and 121 male patients with a median age of 61 years (range 2–88 years). All tumors available for review were classic diffuse non-Hodgkin's lymphoma, for which the phenotype was determined in 220 patients: 212 (96.4%) were B-cell and eight (3.6%) were T-cell type tumors. According to the Revised European—American classification of lymphoid neoplasms, most lesions were diffuse large cell tumors (62%). A total of 196 tumors were reviewed in 127 patients for whom preoperative computerized tomography and magnetic resonance studies were available. There was a single lesion in 66% of the cases, with a supratentorial location in 87%. Tumor location in the basal ganglia, corpus callosum, or fornix, infiltration of the periventricular ependyma, or a mirror pattern, were strongly suggestive of a lesion of lymphomatous origin. The histological diagnosis was obtained after surgical resection in 116 patients, with the remainder undergoing biopsy sampling only. Of the 248 patients studied, 129 (52%) received chemotherapy plus radiation therapy, 60 (24%) received radiation therapy alone, 35 (14%) received chemotherapy alone, and 24 (10%) received no postsurgical treatment.

Conclusions. Using univariate analysis, the authors determined prognostic factors that were significantly associated with a favorable impact on survival including age younger than 60 years, radiation therapy (without evidence of a dose—response relationship), radiation therapy combined with chemotherapy, and chemotherapy consisting of anthracycline. Partial surgical resection was an unfavorable prognostic factor. Multivariate analysis was used to confirm the independent prognostic value of radiation therapy, age, chemotherapy consisting of anthracyclines or methotrexate, and partial surgical resection. This European survey provides a reasonable basis for the treatment of primary intracerebral lymphoma with the following sequence: stereotactic biopsy sampling, chemotherapy with a methotrexate- and anthracycline-based regimen, followed by cranial irradiation.
Use of spiral computerized tomography angiography in patients with subarachnoid hemorrhage in whom subtraction angiography did not reveal cerebral aneurysms
Authors: Hashimoto Hiroyuki , Iida Jun-Ichi , Hironaka Yasuo , Okada Masato , Sakaki Toshisuke
Published: May 2009

Object. Patients with subarachnoid hemorrhage (SAH) in whom angiography does not demonstrate diagnostic findings sometimes suffer recurrent disease and actually harbor undetected cerebral aneurysms. The management strategy for such cases remains controversial, but technological advances in spiral computerized tomography (CT) angiography are changing the picture. The purpose of this prospective study was to examine how spiral CT angiography can contribute to the detection of cerebral aneurysms that cannot be visualized on angiography.

Methods. In 134 consecutive patients with SAH, a prospective search for the source of bleeding was performed using digital subtraction (DS) and spiral CT angiography. In 21 patients in whom initial DS angiography yielded no diagnostic findings, spiral CT angiography was performed within 3 days. Patients in whom CT angiography provided no diagnostic results underwent second and third DS angiography sessions after approximately 2 weeks and 6 months, respectively.

Six patients with perimesencephalic SAH were included in the 21 cases. Six of the other 15 patients had small cerebral aneurysms detectable by spiral CT angiography, five involving the anterior communicating artery and one the middle cerebral artery. Two patients in whom initial angiograms did not demonstrate diagnostic findings proved to have a ruptured dissecting aneurysm of the vertebral artery; in one case this was revealed at autopsy and in the other during the second DS angiography session. A third DS angiography session revealed no diagnostic results in 13 patients.

Conclusions. Spiral CT angiography was useful in the detection of cerebral aneurysms in patients with SAH in whom angiography revealed no diagnostic findings. Anterior communicating artery aneurysms are generally well hidden in these types of SAH cases. A repeated angiography session was warranted in patients with nonperimesencephalic SAH and in whom initial angiography revealed no diagnostic findings, although a third session was thought to be superfluous.