bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemangiopericytoma of the third ventricle
Authors: Abrahams John M. , Forman Mark S. , Lavi Ehud , Goldberg Herbert , Flamm Eugene S. 
Published: May 2009

✓ The authors present the first reported case of a hemangiopericytoma (HPC) occurring in the third ventricle. Most of these lesions are based in the meninges. There is only one other reported case of an intraventricular HPC; in that case the lesion was found in the lateral ventricle.A 40-year-old right-handed man presented with a 3-month history of headaches. Clinical evaluation, including computerized tomography and magnetic resonance imaging studies, revealed a 1-cm enhancing lesion in the third ventricle. Given the findings on the preoperative imaging studies, the lesion was not consistent with some of the more commonly occurring tumors of the third ventricle, namely colloid cysts. A transcortical approach and resection of the lesion was performed without complication. The final pathological findings were consistent with those of an HPC.Hemangiopericytomas rarely occur in the ventricles and may pose a difficult diagnostic dilemma based on their radiographic and gross appearances, as shown in this case. Because of this difficulty, histological confirmation is required to make a definitive diagnosis. These lesions have a propensity to recur and metastasize in the central nervous system and periphery, thus making the goal of treatment a complete surgical resection followed by postoperative radiation therapy in most cases.
Localization of somatosensory function by using positron emission tomography scanning: a comparison with intraoperative cortical stimulation
Authors: Bittar Richard G. , Olivier André , Sadikot Abbas F. , Andermann Frederick , Comeau Roch M. , Cyr Martin , Peters Terrence M. , Reutens David C. 
Published: May 2009

Object. To investigate the utility of [15O]H2O positron emission tomography (PET) activation studies in the presurgical mapping of primary somatosensory cortex, the authors compared the magnitude and location of activation foci obtained using PET scanning with the results of intraoperative cortical stimulation (ICS).Methods. The authors used PET scanning and vibrotactile stimulation (of the face, hand, or foot) to localize the primary somatosensory cortex before surgical resection of mass lesions or epileptogenic foci affecting the central area in 20 patients. With the aid of image-guided surgical systems, the locations of significant activation foci on PET scanning were compared with those of positive ICS performed at craniotomy after the patient had received a local anesthetic agent. In addition, the relationship between the magnitude and statistical significance of blood flow changes and the presence of positive ICS was examined.In 22 (95.6%) of 23 statistically significant (p < 0.05) PET activation foci, spatially concordant sites on ICS were also observed. Intraoperative cortical stimulation was positive in 40% of the PET activation studies that did not result in statistically significant activation. In the patients showing these results, there was a clearly identifiable t-statistic peak that was spatially concordant with the site of positive ICS in the sensorimotor area. All PET activation foci with a t statistic greater than 4.75 were associated with spatially concordant sites of positive ICS. All PET activation foci with a t statistic less than 3.2 were associated with negative ICS.Conclusions. Positron emission tomography is an accurate method for mapping the primary somatosensory cortex before surgery. The need for ICS, which requires local anesthesia, may be eliminated when PET foci with high (> 4.75) or low (< 3.20) t-statistic peaks are elicited by vibrotactile stimulation.
The parasellar region of human infants: cavernous sinus topography and surgical approaches
Authors: Weninger Wolfgang J. , Müller Gerd B. 
Published: May 2009

Object. In this study the authors analyze the peculiarities of the parasellar anatomy and the topography of surgical approaches to the parasellar region (PSR) in human infants.Methods. Forty-nine specimens of the PSR obtained at autopsy were studied using microdissection and histological analysis. Important distances between anatomical landmarks were measured with the aid of a dissecting microscope. One serially sectioned specimen was three-dimensionally reconstructed and analyzed on the computer screen by using the authors' new episcopic reconstruction technique.Conclusions. The anatomy of the infant PSR differs distinctly from that of the adult. The parasellar portion of the internal carotid artery (ICA) does not form a siphon, but takes a straight course, and the venous pathways as well as the cranial and sympathetic nerves have different topographical relationships. Analyses of surgical approaches demonstrate that, in young children, the anterolateral approach can be used to reach the pterygopalatine compartment, the superior ophthalmic vein, and those pathological processes that extend from the orbit into the PSR. The approach via Parkinson's triangle can be used in 45% of cases to access the pathological processes that occur in the voluminous space above and behind the posterior flexure of the parasellar ICA. Taking this route, sympathetic nerve fibers passing through the PSR are not at risk, but some arterial branches that run within the lateral wall of the sinus can complicate this approach.This study presents a guideline that can assist radiologists and neurosurgeons in the planning and performance of interventions within the PSR of neonates and young children.
Correlations between the apparent diffusion coefficient, water content, and ultrastructure after induction of vasogenic brain edema in cats
Authors: Kuroiwa Toshihiko , Nagaoka Tsukasa , Ueki Masato , Yamada Ichiro , Miyasaka Naoyuki , Akimoto Hideaki , Ichinose Shizuko , Okeda Riki , Hirakawa Kimiyoshi 
Published: May 2009

Object. The authors examined the correlation between changes in the apparent diffusion coefficient, regional water content, and tissue ultrastructure after vasogenic brain edema.Methods. Vasogenic edema was induced in the white matter of six cats by cortical cold lesioning. The trace of diffusion tensor (Trace[D]) obtained from magnetic resonance imaging to measure the orientationally averaged water diffusibility was compared with the corresponding tissue water content determined by gravimetric studies and with ultrastructural water localization. Edema fluid had spread to the subcortical and deep white matter by 4.5 hours postlesioning. The increase in Trace(D) showed a significant linear correlation with the increase in tissue water content, both in the subcortical and deep white matter as follows: y = 45.5x − 2367 (r = 0.94) and y = 37.0x − 1769 (r = 0.93), respectively, where x is the water content (gram water/gram tissue) and y the Trace(D) (× 10−6 mm2/second). On histological examination, nerve fibers were found to be dissociated in the white matter and the extracellular space was markedly enlarged with protein-rich fluid. No noticeable hydropic swelling of the cellular components was observed.Conclusions. A linear correlation was observed between increases in Trace(D) and increases in extracellular water volume in in vivo vasogenic brain edema. A similar correlation between the subcortical and deep white matter showing different arrangements of nerve fibers (parallel compared with intermingled, respectively) indicated that measurement of Trace(D) is a suitable parameter for the evaluation of vasogenic brain edema.
Glutathione monoethyl ester and inhibition of the oxyhemoglobin-induced increase in cytosolic calcium in cultured smooth-muscle cells
Authors: Arai Takashi , Takeyama Naoshi , Tanaka Takaya 
Published: May 2009

Object. The mechanism of arterial vasoconstriction caused by oxyhemoglobin production after subarachnoid hemorrhage was investigated.Methods. Using a fluorescent Ca++ indicator (fura-2 acetoxymethyl ester), the change in the cytosolic intracellular Ca++ concentration, [Ca++]i, was measured in cultured rat vascular smooth-muscle cells exposed to oxyhemoglobin and other substances. Oxyhemoglobin induced transient elevation of smooth-muscle cell [Ca++]i in either the presence or absence of ethyleneglycol-bis (β-aminoethylether)-N,N′-tetraacetic acid, indicating that Ca++ released by oxyhemoglobin was derived from [Ca++]i stores. In contrast, methemoglobin had no effect on the smooth-muscle cells. Exposure of the cells to reactive oxygen species generated by xanthine plus xanthine oxidase yielded the same results as with oxyhemoglobin, that is, transient elevation of smooth-muscle cell [Ca++]i. Procaine (a Ca++ channel blocker) failed to inhibit the oxyhemoglobin-induced elevation of [Ca++]i. Ryanodine (a Ca++ channel opener) plus oxyhemoglobin caused markedly greater elevation of [Ca++]i than ryanodine alone, whereas thapsigargin (an adenosine triphosphate [ATP]-dependent Ca++ pump inhibitor) plus oxyhemoglobin had no additional effect when compared with thapsigargin alone. The oxyhemoglobin-induced elevation of [Ca++]i could be blocked by an Fe++ chelator (ferene), but not by an Fe+++ chelator (deferoxamine mesylate). Treatment with either dithiothreitol or glutathione monoethyl ester markedly inhibited the oxyhemoglobin-induced elevation of [Ca++]i.Conclusions. These results indicate that Fe++-catalyzed hydroxyl radicals generated from oxyhemoglobin-derived free radicals induce the elevation of [Ca++]i by inhibiting the ATP-dependent Ca++ pump rather than the Ca++ channels in the sarcoplasmic reticulum and that thiols may prevent Ca++ pump inactivation by inhibiting the oxidation of membrane sulfhydryl groups.
Report of 190 consecutive cases of large acoustic tumors (vestibular schwannoma) removed via the translabyrinthine approach
Authors: Lanman Todd H. , Brackmann Derald E. , Hitselberger William E. , Subin Bill 
Published: May 2009

Object. The choice of approach for surgical removal of large acoustic neuromas is still controversial. The authors reviewed the results in a series of patients who underwent removal of large tumors via the translabyrinthine approach.Methods. The authors conducted a database analysis of 190 patients (89 men and 101 women) with acoustic neuromas 3 cm or greater in size. The mean age of these patients was 46.1 ± 15.6 years. One hundred seventy-eight patients underwent primary translabyrinthine surgical removal and 12 underwent surgery for residual tumor. Total tumor removal was accomplished in 183 cases (96.3%). The tumor was adherent to the facial nerve to some degree in 64% of the cases, but the facial nerve was preserved anatomically in 178 (93.7%) of the patients. Divided nerves were repaired by primary attachment or cable graft. Facial nerve function was assessed immediately after surgery, at the time of discharge, and at 3 to 4 weeks and 1 year after discharge. Excellent function (House—Brackmann facial nerve Grade I or II) was present in 55%, 33.9%, 38.8%, and 52.6% of the patients for each time interval, respectively, with acceptable function (Grades I—IV) in 81% at 1 year. Cerebrospinal fluid leakage that required surgical repair occurred in only 1.1% of the patients and meningitis in 3.7%. There were no deaths.Conclusions. Use of the translabyrinthine approach for removal of large tumors resulted in good anatomical and functional preservation of the facial nerve, with minimum incidence of morbidity and no incidence of mortality. The authors continue to recommend use of this approach for acoustic tumors larger than 3 cm and for smaller tumors when hearing preservation is not an issue.
Magnetic resonance cisternography used to determine precise topography of the facial nerve and three components of the eighth cranial nerve in the internal auditory canal and cerebellopontine cistern
Authors: Ryu Hiroshi , Tanaka Tokutaro , Yamamoto Seiji , Uemura Kenichi , Takehara Yasuo , Isoda Haruo 
Published: May 2009

Object. The detailed anatomy of intracranial structures has been studied mainly in cadavers, but the absence of cerebrospinal fluid and blood pressure in these models distorts normal spatial relationships. The authors investigated the rotation of the facial nerve (FN), superior vestibular nerve (SVN), inferior vestibular nerve (IVN), and cochlear nerve (CN) in the internal auditory canal (IAC) and cerebellopontine cistern in human volunteers and compared their results with those reported in cadaver studies.Methods. The IACs and cerebellopontine cisterns of 30 normal adults (34 sides) were examined using magnetic resonance (MR) cisternography with a heavily T2-weighted two-dimensional fast spin—echo technique. The positions of the four components were unaffected by the presence of the meatal loop of the anterior inferior cerebellar artery in the IAC. The spatial relationship between the FN and SVN was quite constant, but the spatial relationship between the CN and SVN was quite variable: the former changed position, mainly in the IAC, on nine (26.5%) of 34 sides, and in the cerebellopontine cistern on the other sides (73.5%), conflicting with findings in cadaver studies.Conclusions. It is more accurate to describe the CN and IVN as coursing beneath the SVN in either the IAC or cerebellopontine cistern, rather than stating that the three components rotate, as reported in cadaver studies. The MR cisternography studies provided quite detailed information about the topography of the four components and the relationship between the blood vessels and cranial nerves in the IAC and the cerebellopontine cistern.
The acute period of recovery from traumatic brain injury: posttraumatic amnesia or posttraumatic confusional state?
Authors: Stuss Donald T. , Binns Malcolm A. , Carruth Fiona G. , Levine Brian , Brandys Clare E. , Moulton Richard J. , Snow William G. , Schwartz Michael L. 
Published: May 2009

Object. The goal of this study was to characterize more fully the cognitive changes that occur during the period of acute recovery after traumatic brain injury (TBI).Methods. The pattern of performance recovery on attention and memory tests was compared with the results of the Galveston Orientation and Amnesia Test (GOAT). Tests of memory and attention were administered serially to a hospitalized group of patients with TBI of varying severity. The tests differed in their level of complexity and/or requirement for more effortful or strategic processing. The authors found a regular pattern to recovery. As expected, ability to perform on simpler tests was recovered before performance on more effortful ones. The ability to recall three words freely after a 24-hour delay (the operational definition in this study of return to continuous memory) was recovered last, later than normal performance on the GOAT. Ability to perform simple attentional tasks was recovered before the less demanding memory task (recognition); ability to perform more complex attentional tasks was recovered before the free recall of three words after a 24-hour delay. This recovery of attention before memory was most notable and distinct in the group with mild TBI.Conclusions. The period of recovery after TBI, which is currently termed posttraumatic amnesia, appears to be primarily a confusional state and should be labeled as such. The authors propose a new definition for this acute recovery period and argue that the term posttraumatic confusional state should be used, because it more appropriately and completely characterizes the early period of recovery after TBI.
Use of the radial forearm microvascular free-flap graft for cranial base reconstruction
Authors: Schwartz Marc S. , Cohen James I. , Meltzer Toby , Wheatley Michael J. , McMenomey Sean O. , Horgan Michael A. , Kellogg Jordi X. , Delashaw Johnny B. 
Published: May 2009

Object. Reconstruction of the cranial base after resection of complex lesions requires creation of both a vascularized barrier to cerebrospinal fluid (CSF) leakage and tailored filling of operative defects. The authors describe the use of radial forearm microvascular free-flap grafts to reconstruct skull base lesions, to fill small tissue defects, and to provide an excellent barrier against CSF leakage.Methods. Ten patients underwent 11 skull base procedures including placement of microvascular free-flap grafts harvested from the forearm and featuring the radial artery and its accompanying venae comitantes. Operations included six craniofacial, three lateral skull base, and two transoral procedures for various diseases. Excellent results were obtained, with no persistent CSF leaks, no flap failures, and no operative infections. One temporary CSF leak was easily repaired with flap repositioning, and at one flap donor site minor wound breakdown was observed. One patient underwent a second procedure for tumor recurrence and CSF leakage at a site distant from the original operation.Conclusions. Microvascular free tissue transfer reconstruction of skull base defects by using the radial forearm flap provides a safe, reliable, low-morbidity method for reconstructing the skull base and is ideally suited to “low-volume” defects.
Improved survival after aneurysmal subarachnoid hemorrhage: review of management during a 12-year period
Authors: Cesarini Kristina G. , Hårdemark Hans-Göran , Persson Lennart 
Published: May 2009

Object. Based on the concept that unfavorable clinical outcome after aneurysmal subarachnoid hemorrhage (SAH), to a large extent, is a consequence of all ischemic insults sustained by the brain during the acute phase of the disease, management of patients with SAH changed at the authors' institution in the mid-1980s. The new management principles affected referral guidelines, diagnostic and monitoring methods, and pharmacological and surgical treatment in a neurointensive care setting. The impact of such changes on the outcome of aneurysmal SAH over a longer period of time has not previously been studied in detail. This was the present undertaking.Methods. The authors analyzed all patients with SAH admitted to the neurosurgery department between 1981 and 1992. This period was divided in two parts, Period A (1981–1986) and Period B (1987–1992), and different aspects of management and outcome were recorded for each period. In total, 1206 patients with SAH (mean age 52 years, 59% females) were admitted; an aneurysm presumably causing the SAH was found in 874 (72%).The 30-day mortality rate decreased from 29% during the first 2 years (1981–1982) to 9% during the last 2 years (1991–1992) (Period A 22%; Period B 10%; p < 0.0001) and the 6-month mortality rate decreased from 34 to 15% (Period A 26%; Period B 16%; p < 0.001). At follow-up review conducted 2 to 9 years (mean 5.2 years) after SAH occurred, patients were evaluated according to the Glasgow Outcome Scale. Subarachnoid hemorrhage—related poor outcome (vegetative or dead) was reduced (Period A 30%; Period B 18%; p < 0.001). There was an increase both in patients with favorable outcome (good recovery and moderate disability) (Period A 61%; Period B 66%) and in those with severe disability (Period A 9%; Period B 16%; p < 0.01).Conclusions. This study provides evidence that the prognosis for patients with aneurysmal SAH has improved during the last decades. The most striking results were a gradual reduction in mortality rates and improved clinical outcomes in patients with Hunt and Hess Grade I or II SAH and in those with intraventricular hemorrhage. The changes in mortality rates and the clinical outcomes of patients with Hunt and Hess Grades III to V SAH were less conspicuous, although reduced incidences of mortality were seen in some subgroups; however, few survivors subsequently appeared to attain a favorable outcome.
Efficacy of induced hypotension in the surgical treatment of large cavernous sinus cavernomas
Authors: Ohata Kenji , El-Naggar Alaa , Takami Toshihiro , Morino Michiharu , El-Adawy Yousry , El-Sheik Kanan , Inoue Yuichi , Hakuba Akira 
Published: May 2009

Object. Cavernous sinus cavernomas are rare lesions associated with high rates of intraoperative mortality and morbidity resulting from profuse bleeding. In this paper, the authors report their experience in treating five patients with histologically confirmed cavernous sinus cavernomas and describe the efficacy of induced hypotension in facilitating excision of the lesion.Methods. All five patients were women ranging in age from 25 to 54 years, with an average age of 42 years. The mass was small in one and large (> 3 cm in diameter) in four. In one patient with a large mass, cardiac arrest occurred after the craniotomy, and remarkable reduction in the size of the cavernoma was evident on postmortem examination. The other three large lesions were successfully removed piecemeal after induction of hypotension (60–80 mm Hg systolic pressure), which remarkably reduced the mass and the bleeding during surgery. In the remaining patient, who had a small lesion, the cavernoma was removed in one piece.Conclusions. Cavernous sinus cavernoma can be thought of as a cluster of sinusoidal cavities, the size of which varies depending on the systemic blood pressure. During surgery, reduction of the mass and control of bleeding from the cavernoma can be achieved by inducing hypotension, which enables the safe excision of this lesion. This technique should be considered by surgeons resecting a cavernous sinus tumor, especially when cavernoma is suspected.
Theoretical comparison of surgery and radiosurgery in cerebral arteriovenous malformations
Authors: Chang Han Soo , Nihei Hiroshi 
Published: May 2009

Object. Management of patients with cerebral arteriovenous malformations (AVMs) is controversial. Excellent surgical results are obtained in patients with low Spetzler—Martin grades, whereas radiosurgery offers a good alternative with its high obliteration rate. In the absence of randomized studies, physicians must choose a treatment plan based on the currently available data. To support this decision-making process, a mathematical model designed to describe patient survival rates after each treatment option was developed.Methods. The theoretical survival curve in patients undergoing conventional surgery, radiosurgery, or observation was calculated. Theoretical life expectancies in patients with AVMs who presented at various initial ages were calculated for each treatment strategy. A systematic method was also developed to compare the estimated risks of various treatment combinations.Conclusions. Conventional surgery and radiosurgery definitely produced better survival rates than observation. In the comparison of surgery with radiosurgery, radiosurgery was equivalent to surgery with a combined morbidity and mortality rate of approximately 7% for a 20-year-old patient with an unruptured cerebral AVM. Data for other patient ages and treatment combinations are tabulated for use in determining the best treatment strategy. The authors believe that their analysis will provide logical support for the decision-making process involved in the treatment of patients with cerebral AVMs.