Symptomatic T2 vertebral hemangioma in a pregnant woman treated by one stage combination surgery; posterior stabilization and anterior subtotal tumor resection. Case report.

A 27-year-old woman presented with vertebral hemangioma manifesting as sudden onset of paraplegia, and bladder and bowel dysfunction during pregnancy. Magnetic resonance imaging revealed a mass lesion that had infiltrated into the entire T2 vertebral body and expanded to the vertebral canal. Laminectomy from T1 to T3 and biopsy of the lesion were performed. Biopsy confirmed the diagnosis of vertebral hemangioma, but laminectomy resulted in no neurological changes. The patient was transferred to our hospital, where radical treatment comprising embolization of the feeding arteries, posterior stabilization of the vertebrae, and anterior excision of the tumor was performed. Symptoms resolved gradually but steadily, and she made a full recovery by 18 months postoperatively. Radical operation might be extremely effective for extradural vertebral hemangioma, even in the delayed phase or in the presence of severe neurological deficit.

Deficiency of chemokine receptor CCR1 causes osteopenia due to impaired functions of osteoclasts and osteoblasts.

Chemokines are characterized by the homing activity of leukocytes to targeted inflammation sites. Recent research indicates that chemokines play more divergent roles in various phases of pathogenesis as well as immune reactions. The chemokine receptor, CCR1, and its ligands are thought to be involved in inflammatory bone destruction, but their physiological roles in the bone metabolism in vivo have not yet been elucidated. In the present study, we investigated the roles of CCR1 in bone metabolism using CCR1-deficient mice. Ccr1(-/-) mice have fewer and thinner trabecular bones and low mineral bone density in cancellous bones. The lack of CCR1 affects the differentiation and function of osteoblasts. Runx2, Atf4, Osteopontin, and Osteonectin were significantly up-regulated in Ccr1(-/-) mice despite sustained expression of Osterix and reduced expression of Osteocalcin, suggesting a lower potential for differentiation into mature osteoblasts. In addition, mineralized nodule formation was markedly disrupted in cultured osteoblastic cells isolated from Ccr1(-/-) mice. Osteoclastogenesis induced from cultured Ccr1(-/-) bone marrow cells yielded fewer and smaller osteoclasts due to the abrogated cell-fusion. Ccr1(-/-) osteoclasts exerted no osteolytic activity concomitant with reduced expressions of Rank and its downstream targets, implying that the defective osteoclastogenesis is involved in the bone phenotype in Ccr1(-/-) mice. The co-culture of wild-type osteoclast precursors with Ccr1(-/-) osteoblasts failed to facilitate osteoclastogenesis. This finding is most likely due to a reduction in Rankl expression. These observations suggest that the axis of CCR1 and its ligands are likely to be involved in cross-talk between osteoclasts and osteoblasts by modulating the RANK-RANKL-mediated interaction.

Induction of striatal neurogenesis and generation of region-specific functional mature neurons after ischemia by growth factors. Laboratory investigation.

OBJECT: The capacity to replace lost neurons after insults is retained by several regions of adult mammalian brains. However, it is unknown how many neurons actually replace and mature into region-specific functional neurons to restore lost brain function. In this paper, the authors asked whether neuronal regeneration could be achieved efficaciously by growth factor treatment using a global ischemia model in rats, and they analyzed neuronal long-term maturation processes. METHODS: Rat global ischemia using a modified 4-vessel occlusion model was used to induce consistent ischemic neuronal injury in the dorsolateral striatum. To potentiate the proliferative response of neural progenitors, epidermal growth factor and fibroblast growth factor-2 were infused intraventricularly for 7 days from Day 2 after ischemia. Six weeks after ischemia, the number of neurons was counted in the defined dorsolateral striatum. To label the proliferating neural progenitors for tracing studies, 5-bromo-2'-deoxyuridine (BrdU; 150 mg/kg, twice a day) was injected intraperitoneally from Days 5 to 7, and immunohistochemical studies were conducted to explore the maturation of these progenitors. Migration of the progenitors was further studied by enhanced green fluorescent protein retrovirus injection. The effect of an antimitotic drug (cytosine arabinoside) on the neuronal count was also evaluated for contribution to regeneration. To see electrophysiological changes, treated rats were subjected to slice studies by whole-cell recordings. Finally, the effect of neural regeneration was assessed by motor performance by using the staircase test. RESULTS: Following epidermal growth factor and fibroblast growth factor-2 infusion into the lateral ventricles for 7 days beginning on Day 2, when severe neuronal loss in the adult striatum was confirmed (2.3% of normal controls), a significant increase of striatal neurons was observed at 6 weeks (~ 15% of normal controls) compared with vehicle controls (~ 5% of normal controls). Immunohistochemical studies by BrdU and enhanced green fluorescent protein retrovirus injection disclosed proliferation of neural progenitors in the subventricular zone and their migration to the ischemic striatum. By BrdU tracing study, NeuN- and BrdU-positive new neurons significantly increased at 6 and 12 weeks following the treatment. These accounted for 4.6 and 11.0% of the total neurons present, respectively. Antimitotic treatment demonstrated an approximately 66% reduction in neurons at 6 weeks. Further long-term studies showed dynamic changes of site-specific maturation among various neuronal subtypes even after 6 weeks. Electrophysiological properties of these newly appeared neurons underwent changes that conform to neonatal development. These regenerative changes were accompanied by a functional improvement of overall behavioral performance. CONCLUSIONS: Treatment by growth factors significantly contributed to regeneration of mature striatal neurons after ischemia by endogenous neural progenitors, which was accompanied by electrophysiological maturation and improved motor performance. Recognition and improved understanding of these underlying dynamic processes will contribute to the development of novel and efficient regenerative therapies for brain injuries.

Endoscopic microneurosurgery: usefulness and cost-effectiveness in the consecutive experience of 210 patients.

OBJECTIVE: Indications, usefulness, and cost-effectiveness of the endoscope in routine microneurosurgery are not clear. To delineate such aspects, we assessed our experience of endoscopic application and additional cost to use an endoscope. METHODS: Endoscopes were used in 210 patients with cranial base and cisternal pathological features in the previous 7 years. Lesions were located in the extradural cranial base in 78 patients and in the cistern in 132 patients. Rigid lens endoscopes 2.7 to 4 mm in width, 11 to 20 cm in length, and 0 to 70 degrees in angle were used. RESULTS: Endoscopes were used for primary or a significant part of the surgery in 64% of the extradural cranial base procedures. Although endoscopes were used only for visual assistance in 82% of cisternal pathological features, significant benefit was noted in 9% and was not different from cranial base lesions. Eleven patients may have had complications if the endoscope had not been used, and 10 procedures would have been impossible without endoscopic use. Therefore, the number of patients need to treat to experience significant benefits by endoscope was 10. Endoscopic equipment costs an additional US $326 per patient and, hence, significant benefit was the equivalent of US $3260. No permanent complications resulted from the use of the endoscope. CONCLUSION: The endoscope can be applied safely in routine microsurgery with specific equipment and has proven useful in 1 of 10 patients. To perform more effective procedures using endoscopes, we need to develop specially designed instruments usable through a narrow corridor and in an angled field.

Endoscopy-guided removal of spontaneous intracerebral hemorrhage: comparison with computer tomography-guided stereotactic evacuation.

BACKGROUND AND PURPOSE: Spontaneous intracerebral hemorrhage (ICH) continues to be a major medical and socioeconomic problem. While the surgical procedure failed to show benefits over functional outcome, a less invasive and quicker surgical decompression might improve the outcome. The authors introduced endoscopy-guided evacuation in managing ICH and reports the benefits over the conventional method. MATERIALS AND METHODS: Twenty-seven cases underwent endoscopic evacuation of ICH (Group E). The clinical features and outcomes were compared to the retrospective data of 20 cases who underwent computer tomography (CT)-guided stereotactic removal of ICH (Group C). Confidence level less than 0.05 was considered statistically significant. RESULTS: While the clinical features of the two groups were not significantly different except for the ICH volume, outcomes were better in all aspects in Group E. The patients in Group E required shorter operative time (72 min vs 102 min, p < 0.01) with better hematoma evacuation (95.5% vs 75%, p < 0.01), shorter stay in the intensive care unit (ICU; 4.2 days vs 6.9 days, p < 0.01) and less frequent CT scanning (6.4 times vs 8.6 times, p < 0.01) compared to the patients in Group C. Neurological outcome improved significantly in Group E 1 week after surgery (p < 0.01), but not in Group C. Glasgow outcome scale at 6 months were better in Group E than in Group C (p < 0.05). Nine patients (33%) showed good recovery at 6 months postoperatively after endoscopic evacuation of ICH. CONCLUSION: Endoscopic hematoma evacuation provided the quick, adequate decompression of ICH. The outcomes were better than the CT-guided hematoma removal. Further study is necessary to evaluate the real benefit of this surgical procedure over the functional outcome of ICH.

Lymphoplasmacyte-rich meningioma with atypical invasive nature.

A 12-year-old boy presented with a lymphoplasmacyte-rich (LPR) meningioma in the posterior fossa. The tumor was subtotally removed. Histological examination showed the tumor had invaded the normal brain tissue despite its benign grade in the World Health Organization classification. The Ki-67 staining index using MIB-1 monoclonal antibody was relatively high. (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography revealed high uptake in the tumor. These findings indicate the atypical nature of LPR meningioma.

Sarcomatous transformation of clival chordoma after charged-particle radiotherapy. Report of two cases.

Skull base chordomas containing a sarcomatous component are extremely rare. Here the authors report two new cases in which a recurrent tumor with a sarcomatous component appeared after the patient had undergone charged-particle radiotherapy. Histological examinations performed in Case 1 revealed some retention of epithelial features in the sarcomatous component, whereas no such regions were observed in Case 2. Both patients had rapidly deteriorating clinical courses and died within 6 months after diagnosis of the recurrent tumor. The authors discuss the significance of the histological subtypes of these tumors for long-term prognosis and their pathogenetic mechanisms in relation to radiotherapy. Although these sarcomatous transformations are rare in conventional chordomas, a careful histological examination and thorough follow-up imaging studies are crucial when treating patients with such lesions.

p53 potentiates hippocampal neuronal death caused by global ischemia.

Although p53 controls cell death after various stresses, its role in neuronal death after brain ischemia is poorly understood. To address this issue, we subjected p53-deficient (p53-/- and p53+/-) mice (backcrossed for 12 generations with C57BL/6 mice) and wild-type mice (p53+/+) to transient global ischemia by the three-vessel occlusion method. Despite similar severity of ischemia, as shown by anoxic depolarization and cortical blood flow, neuronal death in the hippocampal cornus ammonis (CA)1 region was much more extensive in p53+/+ than in p53-/- mice (surviving neuronal count, 9.3%+/-3.0% versus 61.3%+/-34.0% of nonischemic p53+/+ controls, respectively, P<0.0037). In p53+/- mice, a similar trend was also observed, though not statistically significant (43.5% of nonischemic p53+/+ controls). In p53+/+ mice, p53-like immunoreactivity in hippocampal CA1 neurons was enhanced at 12 h after ischemia, and messenger ribonucleic acid for Bax, a direct downstream target of p53, was also increased. These results indicate that p53 potentiates ischemic neuronal death in vivo and suggest that this molecule could be a therapeutic target in neuronal death after cerebral ischemia.

Endoscopic microneurosurgery: usefulness and cost-effectiveness in the consecutive experience of 210 patients.

OBJECTIVE: Indications, usefulness, and cost-effectiveness of the endoscope in routine microneurosurgery are not clear. To delineate such aspects, we assessed our experience of endoscopic application and additional cost to use an endoscope. METHODS: Endoscopes were used in 210 patients with cranial base and cisternal pathological features in the previous 7 years. Lesions were located in the extradural cranial base in 78 patients and in the cistern in 132 patients. Rigid lens endoscopes 2.7 to 4 mm in width, 11 to 20 cm in length, and 0 to 70 degrees in angle were used. RESULTS: Endoscopes were used for primary or a significant part of the surgery in 64% of the extradural cranial base procedures. Although endoscopes were used only for visual assistance in 82% of cisternal pathological features, significant benefit was noted in 9% and was not different from cranial base lesions. Eleven patients may have had complications if the endoscope had not been used, and 10 procedures would have been impossible without endoscopic use. Therefore, the number of patients need to treat to experience significant benefits by endoscope was 10. Endoscopic equipment costs an additional 326 US dollars per patient and, hence, significant benefit was the equivalent of 3260 US dollars. No permanent complications resulted from the use of the endoscope. CONCLUSION: The endoscope can be applied safely in routine microsurgery with specific equipment and has proven useful in 1 of 10 patients. To perform more effective procedures using endoscopes, we need to develop specially designed instruments usable through a narrow corridor and in an angled field.

Radiation-induced spinal cord cavernous malformation. Case report.

The authors report a case of a 16-year-old girl who presented with progressive gait difficulty 8 years after undergoing spinal radiation therapy for spinal astrocytoma. Magnetic resonance imaging revealed intramedullary multicentric cavity formation in the T4-10 area. Extensive subtotal resection was performed and a pathological examination of the excised tissue demonstrated cavernous malformation with radiation-induced degeneration in the surrounding vessels. This is believed to be the third case of de novo formation of an intramedullary cavernous malformation following spinal radiation therapy.

Intracranial extracerebral glioneuronal heterotopia. Case report and review of the literature.

The authors report a case of intracranial extracerebral glioneuronal heterotopia (IEGH) in an infant. Glioneuronal heterotopias are rare congenital disorders that arise in the head, face, spine, and thoracic cavity. They consist of nodular accumulations of neuronal and glial cells that have developed abnormally, ranging in size from small lesions to large masses. Among heterotopias, IEGHs are relatively rare. They cause various clinical symptoms, depending on their size and location. The neuroimaging studies, histological examinations, and intraoperative findings presented provide insight into the pathogenesis of this disorder. The findings support the separation and detachment theory, which proposes that IEGHs originate from a third telencephalon that erroneously forms between the 4th and 6th week of embryogenesis. More detailed case reports are necessary to understand fully the pathogenesis of IEGHs.

Subdural hematoma associated with dural metastasis--case report--.

A 56-year-old female presented with acute subdural hematoma associated with dural metastasis. The patient had been treated for breast cancer with disseminated bone and lung metastases. Evacuation of the hematoma with local management of the tumor and bleeding successfully improved her neurological condition and she underwent postoperative radiotherapy. This condition is especially associated with dural metastasis from adenocarcinoma (most frequently stomach cancer) and the clinical outcome depends on the general condition of the patient and the status of the coagulation disorders. If the tumors are multiple, as in this case, extreme caution should be paid to recurrent bleeding in the ipsilateral or contralateral side.

Aberrant vertebral artery course in a case of Chiari malformation and occipitoatlantal assimilation. Case report.

tThe authors report an unusual case of a patient with combined vertebral artery and Chiari malformation anomalies. Unless such anomalies are properly recognized prior to decompression and fusion, this condition can have grave surgical consequences. The diagnostic and surgery-related implications of such anomalous codiseases are discussed.

Multifocal pilocytic astrocytomas with ependymal differentiation in the bilateral medial temporal lobes: case report.

A 7-year-old boy presented with headache, visual disturbance, and psychomotor seizures persisting for 7 months. He had mild hemiparesis and homonymous hemianopia on the left. Neuroimaging showed bilateral temporal lobe masses with calcification and cysts. The right temporal mass was subtotally resected. The histological diagnosis was pilocytic astrocytoma with ependymal differentiation and a MIB-1 staining index of up to 8.0%. Postoperatively his hemiparesis and psychomotor seizures disappeared. Adjuvant chemotherapy consisting of carboplatin and vincristine was given followed by radiotherapy. Neuroimaging showed that the bilateral tumors had disappeared and showed no recurrence for 29 months after the diagnosis. Pilocytic astrocytoma usually presents as a solitary mass in the cerebellum or optic pathway with low proliferative activity, but should be included in the differential diagnosis of multifocal tumors arising in the bilateral temporal lobes. Ependymal differentiation with extremely high proliferative activity might be related to this unusual clinical presentation. Intensive treatment is recommended for patients with such specific neuroimaging and histological features.

Functional monitoring for visual pathway using real-time visual evoked potentials and optic-radiation tractography.

OBJECTIVE: It has been difficult to obtain anatomic and functional information about the visual pathway during neurosurgical operations. The aim of this study was to combine the information of the visual evoked potentials (VEPs) and the anatomic navigation of the optic radiation by diffusion tensor imaging-based tractography for functional monitoring of the visual pathway. METHODS: The subjects were two patients with brain lesions adjacent to the visual pathway. Diffusion tensor imaging-based tractography of the optic radiation was performed by selecting appropriate regions of interest and by fractional anisotropy. During surgery, cortical VEPs were recorded continuously under general anesthesia with sevoflurane. In Patient 2, the results of optic radiation tractography were imported to a neuronavigation system to better understand the spatial relationships between the lesions and the visual pathway (functional neuronavigation). RESULTS: In Patient 1, the lesion did not seem to be attached to the optic radiation, and VEP profiles remained stable during resection. In Patient 2, who had a lesion adjacent to the posterior horn of the lateral ventricle, VEPs suddenly diminished when resection reached the optic radiation as illustrated on the neuronavigation system. As a result, complete left hemianopia developed after surgery in Patient 2. CONCLUSION: We confirmed functional correlations of the results of diffusion tensor imaging-based tractography by monitoring intraoperative VEPs. The combination of continuous VEP and optic-radiation tractography is reliable to monitor the visual function and is helpful in performing neurosurgical planning near the visual pathway.

Risk of hemorrhage from an arteriovenous malformation confirmed to have been obliterated on angiography after stereotactic radiosurgery.

OBJECT: Radiosurgery has been widely adopted for the treatment of cerebral arteriovenous malformations (AVMs) in which the practical endpoint is angiographic evidence of obliteration, presumed to be consistent with elimination of the risk of hemorrhage. To test this unverified assumption, the authors followed 236 radiosurgery-treated AVMs between 1 and 133 months (median 77 months) after angiographic evidence of obliteration. METHODS: Four patients experienced hemorrhage between 16 and 51 months after angiographic confirmation of AVM obliteration, and two underwent resection. The histological findings in these patients showed occlusion of the AVM by thickening of the intimal layer with dense hyalinization as well as a small amount of residual AVM vessels and a tiny vasculature. The risks of hemorrhage from these presumaby obliterated AVMs were 0.3% for the annual bleeding risk and 2.2% for the cumulative risk over 10 years. Continuous enhancement of the nidus on computerized tomography (CT) or magnetic resonance (MR) imaging was the only significant factor positively associated with hemorrhage in the statistical analysis (p = 0.0212). CONCLUSIONS: Because the study was based on limited follow-up data, its significance for defining predictive features of hemorrhage after angiographic evidence of obliteration is still indeterminable. Nevertheless, disappearance of the AVM on angiography after radiosurgery does not always indicate total elimination of the disease, especially when CT or MR imaging continues to demonstrate an enhancing lesion. The authors therefore recommend continual follow up even after evidence of AVM obliteration on angiography.

Combined use of tractography-integrated functional neuronavigation and direct fiber stimulation.

OBJECT: The aim of this study was better preoperative planning and direct application to intraoperative procedures through accurate coregistration of diffusion-tensor (DT) imaging-based tractography results and anatomical three-dimensional magnetic resonance images and subsequent importation of the combined images to a neuronavigation system (functional neuronavigation). METHODS: Six patients with brain lesions adjacent to the corticospinal tract (CST) were studied. During surgery, direct fiber stimulation was used to evoke motor responses to confirm the accuracy of CST depicted on functional neuronavigation. In three patients, stimulation of the supposed CST elicited the expected motor evoked potentials. In the other three, stimulation at the resection borders more than 1 cm away from the supposed CST showed no motor response. All patients underwent appropriate tumor resection with preservation of the CST. CONCLUSIONS: Integration of the DT imaging-based tractography information into a traditional neuronavigation system demonstrated spatial relationships between lesions and the CST, allowing for the avoidance of tract injury during lesion resection. Direct fiber stimulation was used for real-time reliable white matter mapping, which served to adjust for any discrepancy between the neuronavigation system data and potentially shifted positions of the brain structures. The combination of these techniques enabled the authors to identify accurate positions of the CST during surgery and to accomplish optimal tumor resections.

Integration of three-dimensional corticospinal tractography into treatment planning for gamma knife surgery.

OBJECT: In the radiosurgical treatment of critically located lesions, the effort to minimize the risk of complication is essential. In this study the integration of diffusion-tensor (DT) imaging-based tractography was clinically applied to treatment planning for gamma knife surgery (GKS). METHODS: Seven patients with cerebral arteriovenous malformations located adjacent to the corticospinal tract (CST) underwent this technique. Data provided by DT imaging were acquired before the frame was affixed to the patient's head and the CST of the DT tractography was created using our original software. Stereotactic three-dimensional imaging studies were obtained after frame fixation and then coregistered with the data from DT tractography. After image fusion of the two studies, the combined images were transported to a GKS treatment-planning workstation. The spatial relationship between the dose distribution and the CST was clearly demonstrated within the 2 hours it took to complete the entire imaging process. The univariate logistic regression analysis of transient or permanent motor complications revealed a significant independent correlation with the volume of the CST that received 25 Gy or more and with a maximum dose to the CST (p < 0.05). CONCLUSIONS: The integration of DT tractography into the GKS treatment planning was highly useful in confirming the dose to the CST during treatment planning.

Functional identification of the primary motor area by corticospinal tractography.

OBJECTIVE: For quick and stable identification of the primary motor area (PMA), diffusion tensor imaging (DTI) data were acquired and corticospinal tractography was mathematically visualized. METHODS: Data sets of DTI, anatomic magnetic resonance imaging, and functional magnetic resonance imaging with finger-tapping tasks were acquired during the same investigation in 30 patients with a brain lesion affecting the motor system. Off-line processing of DTI data was performed to visualize the corticospinal tract, placing a seed area in the cerebral peduncle of the midbrain, where the corticospinal tract is densely concentrated. Somatosensory evoked magnetic fields and intraoperative cortical somatosensory evoked potentials were recorded with electrical stimulation of the median nerve to confirm the results of the corticospinal tractography. RESULTS: Functional magnetic resonance imaging and somatosensory evoked magnetic fields failed to identify the PMA in eight patients (16.7%) and one patient (3.8%) investigated, respectively, because of cortical dysfunctions caused by brain lesions. DTI data were acquired within 3 minutes without patient tasks. Using the appropriate seed area and fractional anisotropy, corticospinal tractography successfully indicated the PMA location in all patients. The suspected PMA and central sulcus locations were confirmed by the cortical somatosensory evoked potentials. CONCLUSION: Corticospinal tractography enables identification of the PMA and is beneficial, particularly for patients who present with dysfunction of the PMA.

The risk of hemorrhage after radiosurgery for cerebral arteriovenous malformations.

BACKGROUND: Angiography shows that stereotactic radiosurgery obliterates most cerebral arteriovenous malformations after a latency period of a few years. However, the effect of this procedure on the risk of hemorrhage is poorly understood. METHODS: We performed a retrospective observational study of 500 patients with malformations who were treated with radiosurgery with use of a gamma knife. The rates of hemorrhage were assessed during three periods: before radiosurgery, between radiosurgery and the angiographic documentation of obliteration of the malformation (latency period), and after angiographic obliteration. RESULTS: Forty-two hemorrhages were documented before radiosurgery (median follow-up, 0.4 year), 23 during the latency period (median follow-up, 2.0 years), and 6 after obliteration (median follow-up, 5.4 years). As compared with the period between diagnosis and radiosurgery, the risk of hemorrhage decreased by 54 percent during the latency period (hazard ratio, 0.46; 95 percent confidence interval, 0.26 to 0.80; P=0.006) and by 88 percent after obliteration (hazard ratio, 0.12; 95 percent confidence interval, 0.05 to 0.29; P<0.001). The risk was significantly reduced during the period after obliteration, as compared with the latency period (hazard ratio, 0.26; 95 percent confidence interval, 0.10 to 0.68; P=0.006). The reduction was greater among patients who presented with hemorrhage than among those without hemorrhage at presentation and similar in analyses that took into account the delay in confirming obliteration by means of angiography and analyses that excluded data obtained during the first year after diagnosis. CONCLUSIONS: Radiosurgery significantly decreases the risk of hemorrhage in patients with cerebral arteriovenous malformations, even before there is angiographic evidence of obliteration. The risk of hemorrhage is further reduced, although not eliminated, after obliteration.