bluuebunny/crossref_metadata_2025 huggingface dataset:
Intracranial compartment volumes in patients with enlarged ventricles assessed by magnetic resonance—based image processing
Authors: Matsumae Mitsunori , Kikinis Ron , Mórocz István , Lorenzo Antonio V. , Albert Marilyn S. , Black Peter McL. , Jolesz Ferenc A.
Published: June 2009

✓ Magnetic resonance image—based computerized segmentation was used to measure the volumes of the brain, gray and white matter components, and to identify regions with prolonged enhancement on T2-weighted imaging, such as periventricular or deep white matter hyperintensities. The authors also determined the volumes of the ventricles and subarachnoid space in control subjects and in patients with: 1) aqueductal stenosis (AS); 2) other causes of obstructive hydrocephalus (OH); 3) Alzheimer's disease (AD); and 4) normal-pressure hydrocephalus (NPH). In AS the volume of the brain was smaller, whereas that of ventricles and subarachnoid cerebrospinal fluid space was larger than that of controls. The decrease in brain volume was due primarily to white matter loss. Although in OH the ventricles were larger, the subarachnoid space was smaller than in controls, presumably due to encroachment by the brain, in which the volume remained unchanged. In AD, loss of both gray and white matter resulted in a smaller brain volume, whereas that of ventricles and subarachnoid space was larger than in controls. In NPH patients, only ventricular volume was greater, whereas all other compartments were similar to controls. The brain normally occupies 87% to 92% of the intracranial volume and consequently, as observed in our patients, relatively small decrements in brain size lead to large increments in ventricular and/or extraventricular volumes. The magnitude of such changes differed markedly among our patient groups, and whether such changes prove useful in clinical assessment and differentiation needs to be determined.
Age-related changes in intracranial compartment volumes in normal adults assessed by magnetic resonance imaging
Authors: Matsumae Mitsunori , Kikinis Ron , Mórocz István A. , Lorenzo Antonio V. , Sándor Tamás , Albert Marilyn S. , Black Peter McL. , Jolesz Ferenc A.
Published: June 2009

✓ Magnetic resonance (MR) image—based computerized segmentation was used to measure various intracranial compartments in 49 normal volunteers ranging in age from 24 to 80 years to determine age-related changes in brain, ventricular, and extraventricular cerebrospinal fluid (CSF) volumes. The total intracranial volume (sum of brain, ventricular, and extraventricular CSF) averaged 1469 ± 102 cm3 in men and 1289 ± 111 cm3 in women. The difference was attributable primarily to brain volume, which accounted for 88.6% of the respective intracranial volumes in both sexes, but was significantly larger in men (1302 ± 112 cm3) than in women (1143 ± 105 cm3). In both, the cranial CSF volume averaged 11.4%. Total intracranial volume did not change with age, although the normalized brain volume of both men and women began to decrease after the age of 40 years. This decrease was best reflected by expansion of the extraventricular CSF volume which, after the age of 50 years, was more marked in men than in women.

The volume of the cranial CSF, as determined by MR image-based computerized segmentation, is considerably larger than traditionally accepted and resides mostly extraventricularly. Expansion of CSF volume with age provides a good index of brain shrinkage although evolving changes and growth of the head with age tend to confound the results.
Morphological study of experimental syringomyelia with kaolin-induced hydrocephalus in a canine model
Authors: Yamada Haruyuki , Yokota Akira , Haratake Joji , Horie Akio
Published: June 2009

✓ In this morphological study the authors investigated whether spinal cord cavitation, produced in young mongrel dogs that had been rendered hydrocephalic by cisternal injection of kaolin, consists of a dilated central canal or intramedullary cavities. Hydrocephalus was noted in 50 of 56 dogs treated with kaolin. Of the 50 hydrocephalic young dogs, 29 were shown to have central canal dilation that was prominent at the thoracic level and 21 to have cervical intramedullary cavities in the posterior column and/or the posterior horn. In 11 dogs from the latter group these cavities were demonstrated to have no communication with the central canal. This finding could not be explained by the hydrodynamic theory.

On histopathological examination, myelomalacia and hemorrhagic infarction following ventricular shunting were noted adjacent to the cervical cavities, which suggested vascular impairment. A perfusion study revealed insufficient blood flow within the cervical cord at the level of the intramedullary cavities. A close correlation between the vascular insufficiency of the cervical cord and the pressure cone resulting from significant hydrocephalus was observed. The latter may cause cervicomedullary compression at the foramen magnum, affecting the venous drainage of the cervical cord below that level, resulting in intramedullary cavitation.

Accordingly, vascular impairment was thought to play a significant role in the development of cervical syrinx formation in our kaolin model. The current results may provide a reasonable explanation for the formation of noncommunicating cervical syringomyelia in Chiari I malformation.
Blocking of glioma proliferation in vitro and in vivo and potentiating the effects of BCNU and cisplatin: UCN-01, a selective protein kinase C inhibitor
Authors: Pollack Ian F. , Kawecki Stephanie , Lazo John S.
Published: June 2009

✓ Seven-hydroxystaurosporine (UCN-01) is a derivative of the nonselective protein kinase inhibitor staurosporine that exhibits significant selectivity for protein kinase C (PKC) in comparison to a variety of other intracellular kinases and appears to be well toleratedin vivoat concentrations sufficient to achieve effective inhibition of PKC. Because recent studies have indicated that the proliferation of malignant gliomas may result from activation of PKC-mediated pathways and, conversely, may be inhibited by blocking PKC, the authors examined the efficacy of this agent as an inhibitor of proliferation in three established and three low-passage malignant glioma cell linesin vitro. A striking inhibition of proliferation was produced by UCN-01 in each of the cell lines, with a median effective concentration of 20 to 100 nM, which correlated with the medianin vitroPKC inhibitory concentration of 20 to 60 nM for this agent in the U-87 and SG-388 glioma cell lines. Inhibition-recovery studies of clonogenic activity indicated that UCN-01 had both cytostatic and cytotoxic effects on the treated cells. Proliferation resumed after short-term (6- and 24-hour) exposures to this agent; in contrast, with longer exposures, recovery of proliferative activity was severely compromised. In addition, UCN-01 enhanced the inhibition of glioma cell proliferation achieved with conventional chemotherapeutic agents, exhibiting synergistic effects with cisplatin and additive effects with 1,3-bis(2-chloroethyl)-1-nitrosourea.In vivostudies in which UCN-01 was administered by continuous intraperitoneal infusion in subcutaneous and intracranial intraparenchymal nude rat models demonstrated significant activity against U-87 glioma xenografts at dose levels that were well tolerated. It is concluded that UCN-01 is an effective agent for the inhibition of glioma proliferationin vitroandin vivoand has potential for clinical applicability in the treatment of human gliomas.
Meningeal sinus histiocytosis mimicking lymphoplasmacyte-rich meningioma
Authors: Kitai Ryuhei , Sato Kazufumi , Kubota Toshihiko , Kabuto Masanori , Kawano Hirokazu , Kobayashi Hidenori , Tsuji Tetsuro
Published: June 2009

✓ Extranodal sinus histiocytosis with massive lymphadenopathy involving the meninges is a rare clinical entity. The authors describe the unusual case of an occipital meningeal lesion in a 25-year-old man in whom they found inflammation of the occipital lobe mimicking lymphoplasmacyte-rich meningioma. The clinical similarities and differences are discussed.
Primary glioblastoma multiforme of the oculomotor nerve
Authors: Reifenberger Guido , Boström Jan , Bettag Martin , Bock Wolfgang J. , Wechsler Wolfgang , Kepes John J.
Published: June 2009

✓ Tumors of the oculomotor nerve are rare and most instances reported have been schwannomas. The authors present clinical, neuroradiological, and neuropathological findings in a 70-year-old woman with a glioblastoma multiforme (GBM) growing primarily in the proximal part of the left oculomotor nerve. The patient presented with a 1-month history of transient diplopia. Neurological examination revealed an incomplete left-sided oculomotor nerve palsy with no further signs of neurological dysfunction. Cranial computerized tomography and magnetic resonance imaging showed a tumor of the left oculomotor nerve without any obvious signs of penetration into the midbrain or upper pons. Following subtotal removal of the tumor, neuropathological examination of the operative specimen revealed a GBM that had grown diffusely within peripheral nerve tissue. Six weeks after surgery, the patient suddenly died of pulmonary thromboembolism. Postmortem examination of the brain confirmed a large leptomeningeal GBM at the left pontomesencephalic junction with complete destruction of the left oculomotor nerve. To the authors' knowledge, this represents the first case of a GBM of the oculomotor nerve, probably originating from glial cells within the most proximal part of the nerve or the adjacent leptomeninges.
Trigeminal neuralgia and hemifacial spasm as false localizing signs in patients with a contralateral mass of the posterior cranial fossa
Authors: Matsuura Nobuki , Kondo Akinori
Published: June 2009

✓ Trigeminal neuralgia and hemifacial spasm were false localizing signs in three patients with contralateral space-occupying mass lesions in the posterior cranial fossa. According to radiological observations, the brainstem was remarkably displaced and distorted toward the side contralateral to the mass in all three cases. In the two cases with trigeminal neuralgia, the fifth cranial nerve was embedded in a thick arachnoid membrane and strongly compressed and angulated between the brainstem and the petrous bone, but there was no apparent vascular involvement. In the case with hemifacial spasm, only the contralateral tumor was removed. Postoperatively, all three patients experienced complete cessation of the symptoms without recurrence. Based on the operative findings, the authors postulate that angulation and distortion of the axis of the cranial nerve due to the contralateral mass, accompanied by thickening of the arachnoid membrane around the nerve, play an important role in false localizing signs, particularly in patients with trigeminal neuralgia.
Embryological basis of some aspects of cerebral vascular fistulas and malformations
Authors: Mullan Sean , Mojtahedi Saeid , Johnson Douglas L. , Macdonald R. Loch
Published: June 2009

✓ The literature on the formation of cerebral veins is reviewed to obtain a better understanding of some cerebrovascular anomalies. Clinical observations such as the entry of the superior ophthalmic vein into the cavernous sinus through the inferior rather than the superior orbital fissure, the relative infrequency of middle cerebral vein backflow in the presence of an extensive cavernous fistula, and the relative infrequency of hemorrhage in relation to the inferior petrosal fistula all relate to the persistence of an older venous pathway. The frequent occurrence of hemorrhage in association with the superior petrosal sinus fistula and the frequent failure of the superior petrosal sinus to connect to the cavernous sinus similarly have an embryological explanation. The frequent association of the vein of Galen aneurysm and an absent or deformed straight sinus probably relates to the time at which the paired internal cerebral veins fuse into one channel. It is speculated that the origins of cerebral venous malformations (CVMs) and arteriovenous malformations (AVMs) probably relate to sequential formation and absorption of surface veins, which occur in human embryonic development mainly in the 40- to 80-mm length interval, although persistent AVM growth is possible even after birth. The frequent absence or anomaly of the middle cerebral vein and its failure to communicate with the cavernous sinus in the presence of both CVMs and AVMs are linked to the late development of that vein and to its even later connection to the cavernous sinus.
Recurrent cerebral arteriovenous malformations after negative postoperative angiograms
Authors: Kader Abraham , Goodrich James T. , Sonstein William J. , Stein Bennett M. , Carmel Peter W. , Michelsen W. Jost
Published: June 2009

✓ Angiography has been considered to be the gold standard to judge the success of treatment for cerebral arteriovenous malformations (AVMs). Patients without residual nidus or early draining veins on postoperative angiograms are considered cured, with the risk of hemorrhage eliminated. A series of five patients with recurrent AVMs after negative postoperative angiography is described. All patients had hemispheric AVMs, presented initially with hemorrhage, and were between 5 and 13 years of age. Recurrence was noted 1 to 9 years later (at 12–16 years of age); after a hemorrhage in three patients, seizures in one, and on follow-up magnetic resonance imaging in one. Four patients underwent angiography that showed recurrence of the AVM at or adjacent to the original site. Three years postsurgery, the fifth patient died from a large intracerebral and intraventricular hemorrhage originating in the previous location of the AVM; however, the patient did not undergo angiography at the time of recurrence. The initial negative angiograms obtained postoperatively in these patients may be explained by postoperative spasm or thrombosis of a small residual malformation. However, in the authors' cumulative experience with 808 patients who have undergone complete surgical removal of AVMs (of whom 667 were older than 18 years of age), no case of recurrent AVM has been observed in an adult. Therefore, actual regrowth of an AVM may occur in children and could be a consequence of their relatively immature cerebral vasculature and may involve active angiogenesis mediated by humoral factors. The present findings argue against the assumption that AVMs are strictly congenital lesions resulting from failure of capillary formation during early embryogenesis. It is concluded that delayed imaging studies should be considered in children at least 1 year after their initial negative postoperative arteriogram to exclude a recurrent AVM.
Overall management outcome of ruptured posterior fossa aneurysms
Authors: Hillman Jan , SäVeland Hans , Jakobsson Karl-Erik , Edner Göran , Zygmunt Stefan , Fridriksson Sten , Brandt Lennart
Published: June 2009

✓ A study of the overall management of ruptured posterior fossa aneurysms was conducted over a 1-year period (1993) in five neurosurgical centers in Sweden, serving a population of 6.93 million people. Forty-nine cases were identified and treated. One-third of the patients were in the seventh or eighth decade of life. Good overall management outcomes at 6 months were achieved in 30 cases (61%). The overall mortality rate was 27%. Patients with Hunt and Hess Grades I and II had a good overall recovery rate of 87%. On admission, 69% of the patients were assigned Hunt and Hess Grades III to V. The impact on patient outcomes of the intraoperative difficulties encountered, especially in the basilar tip area, is stressed. The authors found that delayed operation is not warranted in most cases. Frequent devastating rebleeding was observed among patients not offered early aneurysm clipping and the operative results were not at significant variance between the early and late surgical groups. Only 50% of the patients scheduled for delayed surgery ultimately made a good recovery, whereas 72% of patients scheduled for early operation did so. The data demonstrate that overall management results with posterior fossa aneurysms, comparable to achievements with supratentorial lesions, are within the reach of modern strategies, even in centers not specializing in these problems.
Central nervous system atypical teratoid/rhabdoid tumors of infancy and childhood: definition of an entity
Authors: Rorke Lucy Balian , Packer Roger J. , Biegel Jaclyn A.
Published: June 2009

✓ Clinical and pathological features of 52 infants and children with atypical teratoid/rhabdoid tumor (ATT/RhT) of the central nervous system are defined. This tumor is typically misdiagnosed as a primitive neuroectodermal tumor (PNET) primarily because 70% of ATT/RhTs contain fields indistinguishable from classic PNETs. Separation of these two tumor types is crucial because the prognosis for ATT/RhT is grim even when treatment includes surgery with or without radio- and/or chemotherapy.

These tumors are most common in infants less than 2 years of age. The cases described in this study arose intracranially in all but one instance, although one-third had already spread throughout the subarachnoid space at presentation. Clinical signs and symptoms and radiological features do not distinguish ATT/RhTs from PNETs. The tumors are composed entirely (13%) or partly (77%) of rhabdoid cells. Seventy percent contain fields of typical PNET alone or in combination with mesenchymal and/or epithelial elements. The immunohistochemical profile is unique: epithelial membrane antigen, vimentin, and smooth-muscle actin are positive in the majority of tumors and markers for germ-cell tumors are consistently negative.

Abnormalities of chromosome 22 distinguish ATT/RhTs from PNETs, which typically display an i(17q) abnormality.
Prognosis for mental function in Apert's syndrome
Authors: Renier Dominique , Arnaud Eric , Cinalli Giuseppe , Sebag Guy , Zerah Michel , Marchac Daniel
Published: June 2009

✓ The factors involved in the mental development of patients with Apert's syndrome were studied by the authors, focusing on the age of the patient at operation, associated brain malformations, and the quality of the family environment. Overall, 32% of patients with significant follow-up review had an intelligence quotient (IQ) greater than 70. Age at operation appeared to be the main factor associated with changes in mental development: final IQ was greater than 70 in 50% of patients operated on before 1 year of age versus only 7.1% in patients operated on later in life (p = 0.01). Malformations of the corpus callosum and size of the ventricles played no role in the final IQ, whereas anomalies of the septum pellucidum had a significant effect, with the proportion of patients with an IQ over 70 increasing more than twofold in patients with a normal septum compared with patients with septal anomalies (p < 0.04). Quality of the family environment was the third factor involved in intellectual achievement: only 12.5% of institutionalized children reached a normal IQ level compared to 39.3% of children from a normal family background.
Traumatic subarachnoid hemorrhage and its treatment with nimodipine
Authors: Harders Albrecht , Kakarieka Algirdas , Braakman Reinder , _ _
Published: June 2009

✓ A prospective, randomized, double-blind, placebo-controlled study of nimodipine used to treat traumatic subarachnoid hemorrhage (tSAH) was conducted in 21 German neurosurgical centers between January 1994 and April 1995. One hundred twenty-three patients with tSAH appearing on initial computerized tomography (CT) scanning were entered into the study. Requirements for inclusion included age between 16 and 70 and admission into the study within 12 hours after head injury, regardless of the patient's level of consciousness. Eligible patients received either a sequential course of intravenous and oral nimodipine or placebo treatment for 3 weeks. Patients were closely monitored using clinical neurology, computerized tomography, laboratory, and transcranial Doppler ultrasound parameters.

Patients treated with nimodipine had a significantly less unfavorable outcome (death, vegetative survival, or severe disability) at 6 months than placebo-treated patients (25% vs. 46%, p = 0.02). The relative reduction in unfavorable outcome in the nimodipine-treated group was even higher (55%, p = 0.002) when only patients who complied with the protocol were considered.
Elevated transcranial Doppler flow velocities after severe head injury: cerebral vasospasm or hyperemia?
Authors: Romner Bertil , Bellner Johan , Kongstad Poul , Sjöholm Hans
Published: June 2009

✓ Sixty-seven patients (45 males and 22 females) aged 2 to 70 years (mean 36 years) who had suffered closed head injury were investigated with daily transcranial Doppler (TCD) recordings. A total of 470 TCD recordings (mean 7) were made during Days 1 to 14 after admission. Blood flow velocities were determined in the middle cerebral artery (MCA) and the extracranial internal carotid artery (ICA). Twenty-seven (40%) of the 67 patients demonstrated traumatic subarachnoid hemorrhage (tSAH) on the first computerized tomography (CT) scan after the injury. Flow velocities exceeded 100 cm/second in 22 patients. Eleven (41%) of the 27 patients who showed tSAH on the first CT scan developed velocities greater than 100 cm/second, as compared to 11 (28%) of 40 patients without tSAH on CT. Two patients in whom a thick layer of tSAH was revealed on the first CT scan had MCA flow velocities exceeding 200 cm/second for several days. Measurements of cerebral blood flow (CBF) with single-photon emission CT (SPECT) were performed in six tSAH patients who showed TCD flow velocities exceeding 120 cm/second (uni- or bilaterally) to determine whether the increase in velocity reflected vasospasm or hyperemia. The SPECT studies verified ischemia in five patients but revealed general hyperemia in one. The bilateral increase in MCA flow velocities in the latter case was due to high-volume flow through the MCA secondary to elevated CBF rather than arterial narrowing. In one patient with a thick layer of subarachnoid blood on a CT scan obtained at admission, MCA flow velocities exceeded 220 cm/second bilaterally on Day 8 after the head injury. A SPECT measurement obtained on the same day reflected bilateral ischemia. In this patient flow velocities decreased, with a corresponding normalization of CBF, after 5 days of intravenous nimodipine administration. The MCA/ICA ratio correlated well with the distribution of CBF in the six patients studied using SPECT. This report suggests that vasospasm is an important secondary posttraumatic insult in patients suffering severe head injury and, in some cases, is probably treatable by administration of intravenous calcium channel blockers.
Protective effect of the 5-lipoxygenase inhibitor AA-861 on cerebral edema after transient ischemia
Authors: Baskaya Mustafa K. , Hu Yingan , Donaldson David , Maley Mary , Rao A. Muralikrishna , Prasad M. Renuka , Dempsey Robert J.
Published: June 2009

✓ This study examined the effect of AA-861, a specific 5-lipoxygenase inhibitor, on brain levels of leukotriene C4 (LTC4) and correlated any changes with changes in edema formation and cerebral blood flow (CBF) after transient ischemia in gerbils. Brain levels of LTC4 were observed to be increased at 1, 2, and 6 hours of reperfusion following 20 minutes of occlusion. At 2 hours of reperfusion, a pretreatment dose of 1000 mg/kg of AA-861 was required to inhibit more than 90% of the reperfusion-induced increases in brain LTC4. At this dose, inhibition of LTC4 production was observed at 2 and 6 hours of reperfusion. The specific gravity of both the cortex and subcortex was decreased at 6 hours of reperfusion after 20 minutes of occlusion. At 2 hours of reperfusion, no significant difference was observed in the specific gravity of the cortex and subcortex regions of gerbils pretreated with AA-861 or with vehicle, but at 6 hours of reperfusion significant positive differences were observed. Cerebral blood flow decreased to approximately 10% of preocclusion values during occlusion and returned to near-preocclusion values after 10 minutes of reperfusion. No significant differences were observed in regional CBF in the AA-861- and vehicle-pretreated gerbils during reperfusion. These findings indicate that LTC4 production after transient cerebral ischemia may be an important contributor to the development of cerebral edema and that CBF does not mediate the LTC4-involved development of edema.
Neuroprotective effects of preischemia intraarterial magnesium sulfate in reversible focal cerebral ischemia
Authors: Marinov Marin B. , Harbaugh Kimberly S. , Hoopes P. Jack , Pikus Harold J. , Harbaugh Robert E.
Published: June 2009

✓ The known cytoprotective properties of MgSO4led the authors to study its effects on infarct size in rats when administered intraarterially before reversible focal ischemia. Following an intracarotid infusion of MgSO4in the amount of 30 mg/kg (24 animals), 90 mg/kg (18 animals), or an equal volume of vehicle (23 animals), middle cerebral artery occlusion was produced in rats by means of an intraluminal suture technique. Reperfusion occurred after 1.5 (42 animals) or 2 hours (23 animals) of ischemia.

Automated, volumetric measurements of 2′,3′,5′-triphenyl-2H-tetrazolium chloride—stained coronal brain sections demonstrated a statistically significant decrease in infarct size for MgSO4treatment groups compared to controls. Cytoprotection was greater in animals subjected to 1.5 hours of ischemia (28.4% reduction in infarct volume, p ≤ 0.001, Student's t-test), than in those having 2 hours of ischemia (19.3% reduction, p < 0.05). Animals given 90 mg/kg MgSO4prior to 1.5 hours of ischemia (12 animals) showed a 59.8% reduction in infarct volume compared to controls (11 animals, p < 0.001) and a 43.1% reduction compared to the 30 mg/kg group (11 animals, p < 0.001). Analysis of variance demonstrated the statistically significant effects of MgSO4doses on infarct volume across all groups (F = 22.95, p < 0.0001).

The neuroprotective effect of intraarterial MgSO4in this model is robust, dose dependent, and related to the duration of ischemia. The compound may be valuable for limiting infarction if given intraarterially before induction of reversible ischemia during cerebrovascular surgery.
Synthetic fibronectin peptides and ischemic brain injury after transient middle cerebral artery occlusion in rats
Authors: Yanaka Kiyoyuki , Camarata Paul J. , Spellman Stephen R. , McCarthy James B. , Furcht Leo T. , Low Walter C. , Heros Roberto C.
Published: June 2009

✓ Leukocytes play an important role in the development of ischemia—reperfusion injury. This study was conducted to ascertain whether synthetic peptides corresponding to the cell- and heparin-binding sequences of fibronectin that disturb leukocyte adhesion molecules were effective in neuronal protection after transient focal cerebral ischemia in rats. The authors evaluated the efficacy of peptides on infarction size, leukocyte infiltration in the ischemic tissue, and neurological outcome in rats subjected to 1 hour of cerebral ischemia and 48 hours of reperfusion. Twenty-one animals were divided into three groups: transient ischemia without treatment (Group I), transient ischemia with administration of vehicle (Group II), and transient ischemia with administration of fibronectin peptides (Group III). The mean myeloperoxidase activity (U/g wet wt) in the ischemic area was as follows: Group I, 0.19% ± 0.05; Group II, 0.21% ± 0.03; and Group III, 0.08% ± 0.02. The mean size of the infarction as a percentage of the total hemispheric volume was as follows: Group I, 38.35% ± 1.34%; Group II, 39.21% ± 2.42%; and Group III, 25.81% ± 4.87%. Group III showed a significant decrease in myeloperoxidase activity in the lesion and the infarction size was smaller when compared to Groups I and II (p < 0.05). The neurological grade in Group III was significantly better than in Groups I and II at 48 hours after reperfusion (p < 0.01). This study is the first to explore the therapeutic potential of synthetic fibronectin peptides in brain protection after transient focal ischemia, and the results also serve as a basis for studies of important cellular and molecular events that contribute to tissue damage.
Induction of HSP70 in rat brain following subarachnoid hemorrhage produced by endovascular perforation
Authors: Matz Paul G. , Sundaresan Sanjoy , Sharp Frank R. , Weinstein Philip R.
Published: June 2009

✓ Current experimental research on subarachnoid hemorrhage (SAH) has been limited by the lack of a small-animal model that physiologically resembles SAH and consistently demonstrates acute and delayed cellular injury. Recently, a model for inducing SAH by endovascular perforation of the internal carotid artery has been developed in the rat. This model physiologically resembles SAH. However, little histological data detailing cellular injury after SAH are available in this or other models. Using immunocytochemistry, the authors investigated the induction of the 70-kD heat shock protein, HSP70, a sensitive marker for cellular stress or injury in the brain, 1 and 5 days following endovascular SAH. The authors also used the conventional histological techniques of cresyl violet and hematoxylin and eosin staining to investigate cellular damage 1 and 5 days after the endovascular SAH.

One day following the SAH, HSP70 was induced in all six animals examined in multiple anatomical regions, including the basal forebrain, thalamus, neocortex, striatum, and hippocampus. This HSP70 induction was observed in multiple vascular distributions bilaterally. Immunostaining with HSP70 occurred primarily in neurons but also was observed in glia and endothelium. Five days after the SAH, a similar but more intense pattern of HSP70 immunostaining was observed in all eight animals examined. Specifically, HSP70 immunoreactivity was observed in at least one region of the hippocampus more often at 5 days (six of eight animals) than at 1 day (one of six animals, p < 0.05, one-tailed Fisher's exact test). No HSP70 immunostaining was observed in control animals at 1 day or at 5 days. Conventional histology demonstrated foci of ischemic neuronal damage and cellular necrosis; however, HSP70 immunocytochemistry detailed cellular injury far better than conventional histology in all animals tested at both 1 day and 5 days.

Our results demonstrate that HSP70 is induced in multiple regions and cell types 1 day and 5 days following endovascular SAH. Because ischemia is a known inducer of stress genes, the authors propose that acute and delayed ischemia are the processes responsible for the induction of HSP70 that was observed at 1 day and 5 days, respectively. Investigation of HSP70 induction following endovascular SAH may also serve as the basis for a new, inexpensive animal model to assess potential therapeutic interventions.
Prognostic value of flow cytometry and correlation to some conventional prognostic factors: a retrospective study of archival specimens of 134 astrocytomas
Authors: Vavruch Ludek , Nordenskjöld Bo , Carstensen John , Eneström Sverker
Published: June 2009

✓ The S-phase fraction and the DNA ploidy type in 134 astrocytomas (18 Grade II, 46 Grade III, and 70 Grade IV astrocytomas) were studied using flow cytometry in a retrospective study of archival tumor specimens. A high grade of malignancy was associated with both a high S-phase fraction (p < 0.0001) and an aneuploid DNA pattern (p < 0.0001). There was no aneuploid DNA pattern found in the fibrillary astrocytomas (World Health Organization (WHO) Grade II); whereas the aneuploid pattern was observed in 80% of all the glioblastomas multiforme (WHO Grade IV). The age and gender of the patients were not significantly related to the flow cytometry parameters. The survival of patients with Grade II or III astrocytomas was significantly longer when their tumors exhibited a tetraploid DNA pattern or had a low S-phase fraction. In patients with Grade IV tumors, there was no correlation between length of survival and either the DNA ploidy or the S-phase fraction.

In a multivariate Cox regression analysis of data obtained in patients with Grade II and III astrocytomas, age, grade of malignancy, DNA ploidy, and S-phase fraction were independent prognostic factors.
Agenesis of the corpus callosum: female monozygotic triplets
Authors: Ruge John R. , Newland T. Simone
Published: June 2009

✓ A case of identical (monozygotic) triplets, two of whom have agenesis of the corpus callosum, is presented. Prenatal ultrasonography and magnetic resonance imaging revealed two of the triplets to have agenesis of the corpus callosum and the third triplet to have an intact corpus callosum. No such case has been reported in the literature. Theories of the etiology and pathogenesis of corpus callosum agenesis are discussed. In this case, unequal X-inactivation as related to the twinning process is implicated as the cause of the agenesis.
Monstrous, crablike hypertrophy of the cerebellar vermis and its relationship with Lhermitte—Duclos disease
Authors: de León Guillermo A. , Grant John A. , Darling Crystal F.
Published: June 2009

✓ The case of an infant with a peculiar tumorous malformation of the cerebellum is described. The tumor apparently developed as an exophytic, hypertrophic sprout of the inferior vermis. It had a monstrous appearance resembling a crab, with a metameric body and multiple pairs of limbs attached to the folia of both cerebellar hemispheres. Histologically, the lesion was formed by poorly differentiated neuroepithelial cells without any evidence of organization into nuclei, cortex, or fascicles. Clinically, the tumor behaved in an indolent manner and did not regrow after subtotal surgical resection. Because of its gross appearance and its biological behavior, this unusual hamartoblastomatous growth is readily distinguished from medulloblastoma. The morphology of the cerebellum in Lhermitte—Duclos disease is reviewed, and a new interpretation of its basic structure is proposed. This and other known types of cerebellar hypertrophy are different from the malformation in the present case.
Aplasia cutis congenita
Authors: Nichols Dennis D. , Bottini Anthony G.
Published: June 2009

✓ The authors report the use of intraoperative tissue expansion in the treatment of a neonate with aplasia cutis congenita, a congenital defect of the scalp and skull. The case for immediate surgical intervention is presented, and intraoperative tissue expansion and cranioplasty are recommended as components of an effective surgical approach.
Reconstruction of irreparable brachial plexus injuries with reinnervated free-muscle transfer
Authors: Doi Kazuteru , Sakai Kazuhiro , Fuchigami Yasunori , Kawai Shinya
Published: June 2009

✓ The complete avulsion of the brachial plexus is a severe injury usually caused by high-energy trauma. Even with the advent of modern microsurgical techniques, many patients have been rendered severely handicapped following this injury. The authors present a new reconstructive procedure that uses a microsurgical reinnervated free-muscle transfer to return prehensile function to an upper limb that is completely paralyzed. Although the procedure is still preliminary, a successful case is briefly described.
Anterior cervical interbody fusion using autogeneic and allogeneic bone graft substrate: a prospective comparative analysis
Authors: Bishop Randolph C. , Moore Karen A. , Hadley Mark N.
Published: June 2009

✓ The authors conducted a prospective study of 132 patients requiring interbody fusion without instrumentation following anterior cervical discectomy to compare the efficacy of tricortical iliac crest allograft versus autograft fusion substrates. The objectives of the study were to assess the potential differences in interspace collapse, angulation, maintenance of cervical alignment and lordosis, and clinical and radiographic fusion success rates between the two fusion substrates. The impact of habitual cigarette smoking on fusion rates was also examined.

Autograft tricortical iliac crest bone was found to be superior to allograft bone as an interbody fusion substrate after both single- and multiple-level anterior cervical decompression procedures with respect to maintenance of cervical interspace height, interspace angulation, and radiographic and clinical fusion success rates. Cigarette consumption had a significant adverse effect on successful anterior cervical interbody fusion for both autograft and allograft substrate, an effect that was most pronounced among smokers treated with allograft bone (p = 0.004).
Single-stage posterior vertebrectomy and replacement combined with posterior instrumentation for spinal metastasis
Authors: Akeyson Edward W. , McCutcheon Ian E.
Published: June 2009

✓ The authors present a series of 25 patients who underwent single-stage complete spondylectomy, vertebral body reconstruction, and posterior segmental spinal stabilization for malignant metastatic disease involving multiple columns of the thoracolumbar spine. Patients were selected for this approach primarily because they were poor candidates for a transcavitary or lateral extracavitary approach or because the tumor involved both anterior and posterior columns of the spine. The operative approach used combines radical local resection of tumor via a bilateral transpedicular route, methylmethacrylate vertebral body reconstruction, and Luque rectangle stabilization in a single operation. Following surgery, the majority of patients experienced improvement in their neurological status, reduction in pain, or both. Most patients were functionally improved, or at least no worse, and spinal alignment was maintained in all. There was one local recurrence in a long-term survivor. Complications included cerebrospinal fluid fistulas, migrating graft material, and wound healing problems. The authors conclude that this surgical approach is safe and feasible for the radical resection of vertebral metastasis when combined with reconstruction and stabilization. This technique represents a useful alternative to other commonly used surgical approaches for the treatment of spinal metastases, and it should aid surgeons in selecting the optimum approach for individual patients.
Surgical outcome after repeated transsphenoidal surgery in acromegaly
Authors: Long Hélène , Beauregard Hugues , Somma Maurice , Comtois Ronald , Serri Omar , Hardy Jules
Published: June 2009

✓ Transsphenoidal selective adenomectomy is the most efficient primary treatment for acromegaly. However, management of persistent or recurrent disease remains controversial. The objective of the present study was to evaluate the early and long-term efficacy and safety of a second transsphenoidal surgery performed in those cases. The results of a retrospective study of 16 patients undergoing reoperation by the senior author (J.H.) between 1970 and 1991 are reported. Reoperation was performed for persistent or progressive acromegaly in 11 patients, visual impairment in four, and disease recurrence in one. Normalization of growth hormone (GH) was defined as a basal GH level of less than 5µg/L and suppression to less than 2 µg/L during the oral glucose tolerance test. Long-term follow-up data were available in 15 patients.

The second transsphenoidal surgery induced a greater than 50% decrease of GH level in 11 patients. Three (19%) of 16 patients were cured according to the authors' criteria and remained so after 2, 7, and 20 years. Two more patients had a postoperative basal GH level of less than 5 µg/L but incomplete suppression during the oral glucose tolerance test. Thus, a total of five patients (31%) achieved a basal GH of less than 5 µg/L. One other patient who had no initial improvement after the second transsphenoidal surgery had spontaneous normalization of his GH level after 13 years. The following complications of the second surgery occurred in three patients: one subarachnoid hemorrhage, two new visual field defects, one cranial nerve palsy, and one meningitis. Moreover, 10 patients (62.5%) developed one or more new pituitary hormone deficiencies. In conclusion, reoperation for persistent or recurrent acromegaly has low success and high complication rates. According to the authors' experience, this procedure should be reserved for patients unresponsive to other forms of therapy or with progressive visual impairment despite medical therapy.
Intrinsic tumors of the insula: a prospective surgical study of 30 patients
Authors: Zentner Josef , Meyer Bernhard , Stangl Armin , Schramm Johannes
Published: June 2009

✓ Intrinsic insular tumors are frequently excluded from surgical treatment. The authors propose a more extensive approach to these lesions based on the results of this prospective series. From September 1993 to January 1995, 30 patients (18 males and 12 females; mean age 42 years) harboring benign (15 patients) or malignant (15 patients) tumors involving the insula underwent surgical treatment. The dominant and nondominant hemispheres were both affected in 15 cases. Two groups were defined on the basis of preoperative magnetic resonance (MR) imaging: 14 lesions were restricted to the insula and the corresponding opercula; the other 16 lesions also involved other mesocortical and/or allocortical areas. Most patients displayed only mild preoperative symptoms. The median score according to the Karnofsky performance scale was 90. Microsurgical removal was achieved via a transsylvian approach in nine cases and via a frontal and/or temporal approach in 21 cases. According to early postoperative MR imaging, complete tumor removal (100%) was seen in five patients, nearly complete (> 80%) in 21, and incomplete resection (50%–80%) in four patients. There was no operative mortality; 19 patients (63%) experienced immediate postoperative morbidity, including reduced performance. After a mean follow-up review of 8.5 months two of 21 patients suffered permanent deficits, accounting for an overall operative morbidity of 10%. At the mean time of review, three patients with Grade IV tumors had died of tumor recurrence. The authors conclude that low-grade intrinsic insular tumors, as well as Grade III tumors, can be removed with favorable results in the majority of patients. Surgery to excise glioblastomas should only be considered for patients with good preoperative performance and young age.
A novel computer-assisted volumetric stereotactic approach for resecting tumors of the posterior parahippocampal gyrus
Authors: Weiner Howard L. , Kelly Patrick J.
Published: June 2009

✓ The authors report their experience using a novel surgical approach for resecting tumors located in the posterior parahippocampal gyrus. Prior attempts to resect epileptogenic foci in this location have been limited by a significant risk of injury to lateral temporal lobe cortical and vascular structures. To avoid these potential complications, the authors have used a lateral occipitosubtemporal, computer-assisted stereotactic volumetric approach to resect radiographically defined tumors in seven patients with intraaxial neoplasms of the posteromedial temporal lobe. This series included one female and six male patients, ranging in age from 15 to 67 years, who presented with seizures, visual field loss, or headache. Gross-total resection of three high-grade gliomas, two gangliogliomas, and one mixed glioma was accomplished with no permanent morbidity or operative mortality. The authors conclude that this approach is advantageous for resecting tumors in this location because, by avoiding unnecessary brain resection or retraction, it significantly reduces the risk of injury to lateral temporal lobe structures, helps maintain precise spatial and anatomical orientation for the surgeon, and, like all computer-assisted volumetric approaches, delineates the margin between the tumor and surrounding neural tissue.
Frameless stereotaxy with real-time tracking of patient head movement and retrospective patient—image registration
Authors: Ryan Martin J. , Erickson Robert K. , Levin David N. , Pelizzari Charles A. , Macdonald R. Loch , Dohrmann George J.
Published: June 2009

✓ The accuracy of a novel frameless stereotactic system was determined during 10 surgeries performed to resect brain tumors. An array of three charge-coupled device cameras tracked the locations of infrared light-emitting diodes on a hand-held stylus and on a reference frame attached to the patient's skull with a single bone screw. Patient—image registration was achieved retrospectively by digitizing randomly chosen scalp points with the system and fitting them to a scalp surface model derived from magnetic resonance (MR) images. The reference frame enabled continual correction for patient head movements so that registration was maintained even when the patient's head was not immobilized in a surgical clamp. The location of the stylus was displayed in real-time on cross-sectional and three-dimensional MR images of the head; this information was used to predict the locations of small intracranial lesions. The average distance (and standard deviation) between the actual position of the mass and its stereotactically predicted location was 4.8 ± 3.5 mm. The authors conclude that frameless stereotaxy can be used for accurate localization of intracranial masses without resorting to using fiducial markers during presurgical imaging and without immobilizing the patient's head during surgery.
Neuroendoscopic approach to arachnoid cysts
Authors: Schroeder Henry W. S. , Gaab Michael R. , Niendorf Wulf-Rüdiger
Published: June 2009

✓ A prospective study of seven consecutive patients with congenital arachnoid cysts treated endoscopically is reported. The ages of the patients at the time of diagnosis ranged from 6 to 47 years with three patients under 15 years. Two cysts were located in the posterior cranial fossa, four in the middle cranial fossa, and one in the suprasellar—prepontine area. The patients' symptoms included headache, seizures, vomiting, nausea, dizziness, balance problems, and precocious puberty. The authors performed cystocisternostomies and ventriculocystostomies via burr holes with the aid of a universal neuroendoscopic system. Minor bleeding was easily controlled by rinsing. In one case, the endoscopic procedure had to be abandoned because of significant bleeding, which obscured a clear operative view, and an open microsurgical cyst fenestration was performed. The follow-up review periods in this group of patients ranged from 15 to 30 months. There was no mortality or morbidity. Symptoms were relieved in five patients and improved in one. Precocious puberty in one case continued. In six cases, follow-up magnetic resonance images or computerized tomography scans revealed a decrease in the size of the cysts. Although the follow-up period is too short to make statements on long-term outcome, the authors recommend the minimally invasive endoscopic approach for treatment of arachnoid cysts as the first therapy of choice. Should the endoscopic procedure fail, established treatment options such as microsurgical fenestration or cystoperitoneal shunting can subsequently be performed without causing additional risk to the patient.