Three-Dimensional (3D) Microcatheter Shaping Using Touch Screen Devices for Cerebral Aneurysm Coil Embolization

OBJECTIVE

In cerebral aneurysm coil embolization, proper microcatheter shaping is crucial to reduce complications and achieve sufficient embolization. Shaping a microcatheter in 3 dimensions (3D) is often required but can be challenging. We assessed the usefulness of a novel shaping on screen (SOS) method that displays real-size 3D rotational angiography (RA) images on a touch screen device during cerebral aneurysm embolization to facilitate 3D microcatheter shaping.

METHODS

In this study, 18 patients with cerebral aneurysm treated with this technique were included. Real-size 3D-RA images obtained during the embolization procedure were displayed on the touch screen device, which allowed for real-time manipulation. The shape of the microcatheter was adjusted to conform to the curvature of the vessel by swiping the touch screen device and bending the mandrel accordingly. We assessed the clinical and angiographic results, along with the accuracy and stability of the microcatheter.

RESULTS

No procedure-related complications were observed. The mean packing density was 41% ± 12%. In all but 1 case, microcatheters were inserted into the aneurysms without guidewire assistance. After coiling, all microcatheter forms were stable.

CONCLUSIONS

Three-dimensional (3D) microcatheter shaping using touch screen devices during cerebral aneurysm coil embolization may be simple and safe and can achieve high packing density of aneurysms.

Pituitary adenoma presenting as isolated oculomotor nerve palsy

Background

Isolated oculomotor nerve palsy is a relatively uncommon symptom of pituitary adenoma that usually occurs in association with pituitary apoplexy or cavernous sinus (CS) invasion.

Case Description

We report two cases of relatively small pituitary adenomas with neither apoplexy nor CS invasion presenting as isolated oculomotor nerve palsy. Both patients presented with gradually worsening diplopia, without headache or visual field defects. Magnetic resonance imaging (MRI) showed a pituitary tumor with no evidence of intratumoral hemorrhage. Computed tomography revealed a lateroposterior extension of the tumor with the erosion of the posterior clinoid process. Constructive interference in steady-state MRI revealed compression of the oculomotor nerve by the tumor at the oculomotor triangle. The patients underwent endoscopic transsphenoidal surgery, and the intraoperative findings showed that the tumors did not invade the CS. The tumors were completely resected, and the oculomotor palsies resolved fully.

Conclusion

These cases illustrate the need to consider isolated oculomotor nerve palsy as an initial manifestation of a relatively small pituitary adenoma with neither apoplexy nor CS invasion. Based on the characteristic radiological findings, early surgical treatment is recommended to preserve oculomotor function.

Clinicopathologic analysis of pineal parenchymal tumors of intermediate differentiation: a multi-institutional cohort study by the Kyushu Neuro-Oncology Study Group

PURPOSE

Pineal parenchymal tumors of intermediate differentiation (PPTIDs), which were recognized in the 2007 World Health Organization (WHO) classification, are rare, accounting for less than 1% of all central nervous system tumors. This rarity and novelty complicate the diagnosis and treatments of PPTID. We therefore aimed to evaluate the clinicopathological significance of this tumor.

METHODS

At 11 institutions participating in the Kyushu Neuro-Oncology Study Group, data for patients diagnosed with PPTID were collected. Central pathology review and KBTBD4 mutation analysis were applied to attain the diagnostically accurate cohort.

RESULTS

PPTID was officially diagnosed in 28 patients: 11 (39%) with WHO grade 2 and 17 (61%) with WHO grade 3 tumors. Median age was 49 years, and the male:female ratio was 1:2.1. Surgery was attempted in all 28 patients, and gross total resection (GTR) was achieved in 46% (13/28). Adjuvant radiotherapy and chemotherapy were administered to, respectively, 82% (23/28) and 46% (13/28). The 5-year progression-free survival (PFS) and overall survival rates were 64.9% and 70.4% respectively. Female sex (p = 0.018) and GTR (p < 0.01) were found to be independent prognostic factors for PFS and female sex (p = 0.019) was that for OS. Initial and second recurrences were most often leptomeningeal (67% and 100% respectively). 80% (20/25) of patients harbored a KBTBD4 mutation.

CONCLUSIONS

Female sex and GTR were independent prognostic factors in our patients with PPTID. Leptomeningeal recurrence was observed to be particularly characteristic of this tumor. The rate of KBTBD4 mutation observed in our cohort was acceptable and this could prove the accuracy of our PPTID cohort.

SPDR-2 DEVELOPMENT OF A NOVEL THERAPEUTIC STRATEGY AGAINST MEDULLOBLASTOMA TARGETING MYC

Medulloblastoma (MB) is the most common pediatric malignant brain tumor, with aggressive behavior and central nervous system dissemination. Standard of care for medulloblastoma include surgery, chemotherapy with platinum agent, and craniospinal radiation. If patients survived with these intensive treatments, frequently faced treatment-related adverse events. Therefore, development of novel therapeutic strategy is an important issue. Driver mutation underlying MB pathogenesis have been discovered, and molecular profiling led to the identification of subgroups; Wingless (WNT), Sonic Hedgehog(SHH), Group3, and Group4. Group 3, especially the group with MYC/MYCN amplification/overexpression confer a poor prognosis. Myc is attracting as a therapeutic target, however, to date, no drugs have been developed that target myc. We had found that N-myc downstream regulated gene-1 (NDRG1) protein expression is a good prognostic factor in glioblastoma, a representative of adult malignant brain tumors, and that Differentiation inducing factor-1 (DIF-1) increased NDRG1 expression. We reported that DIF-1 crossed the Blood-Brain Barrier and could be an effective treatment for GBM in vivo. In this research process, we found that DIF-1 markedly reduced Myc expression in patient-derived glioblastoma stem cells with MYC/MYCN amplification. Based on this result, we found that DIF-1 decreased Myc expression and inhibited cell survival/proliferation even in medulloblastoma cell lines with MYC/MYCN amplification.

In this presentation, we will present the results obtained in the research of a novel Myc-targeted therapy using DIF-1 for MB with MYC/MYCN amplification.

STMO-14 VALIDATION OF SURGICAL METHODS FOR GLIOMA AROUND THE MOTOR CORTEX

Surgery for glioma around the primary motor area (primary MA) including premotor area (PA) and supplementary motor area (SMA) is performed by general anesthesia with motor evoked potential, called asleep surgery (Asleep S) or awake surgery (Awake S). The literature has shown that there is no difference in tumor removal rate and preservation of neurological function between the two methods. We retrospectively studied 14 patients who underwent craniotomy for glioma of the frontal lobe at our hospital, and 19 surgeries with contrast-enhancing lesions or T2 high-signal areas in the motor area. Tumor primary location was PMA: 6, PMA/ primary MA: 5, primary MA: 2, SMA 6 surgeries. All surgeries identified central sulcus by SEP and monitored transcranial and transcortical MEP. 11 surgeries were Asleep S and 8 were Awake S. Of the 11 Asleep S surgeries, 10 were high grade glioma with contrast on preoperative imaging. Of the 8 Awake S surgeries, 7 were lower grade gliomas, and most of these surgeries were performed for multiple recurrences. In Awake S, difficulties of assessment of motor function arose when the PMA and SMA were removed early in the surgery. In the case of Asleep S, to clarify the criteria for MEP warning signs is necessary, while in Awake S, the knowledge that how much motor decline is tolerated in voluntary movements need. In the case of Asleep S, to clarify the criteria for MEP warning signs is necessary, while in Awake S, the knowledge that how much motor decline is tolerated in voluntary movements need. In addition, the order of resection to avoid SMA syndrome and to evaluate motor function is important. We summarize the literatures and discuss these points for surgical strategy in glioma around motor area.

Microsurgical Approach for True Posterior Communicating Artery Aneurysms: Literature Review and Illustrative Case

True posterior communicating artery (PCoA) aneurysms are rare. Although true PCoA aneurysms have been reported to be located close to the internal carotid artery, at the middle part of PCoA, or close to the posterior cerebral artery; the best surgical approach to treat true PCoA aneurysms in each location remains unclear. We conducted a literature review using data from PubMed. Data on demographics, location, and projecting direction of the aneurysm, surgical approach, and surgical complications were collected. A total of 47 true PCoA aneurysms were included. Twenty-nine aneurysms originated from the proximal portion, 10 from the middle portion, and 6 from the distal portion; there were two giant aneurysms. The ipsilateral pterional approach was used for 37 true PCoA aneurysms (27 in proximal portion, 8 in middle portion, and 2 in distal portion of PCoA). The anterior temporal approach was used for two distal-portion aneurysms and one giant aneurysm. The anterior subtemporal approach was used for one distal-portion aneurysm. The subtemporal approach was used for two middle-portion aneurysms and one giant aneurysm. The contralateral pterional approach was used for two proximal-portion and one distal-portion aneurysms. Although most true PCoA aneurysms can be treated by the pterional approach, other means such as anterior temporal and subtemporal approaches can be applicable for aneurysms in the middle and distal portions of the PCoA or giant aneurysms. Surgeons should select an appropriate approach for each aneurysm while considering the advantages and disadvantages of each technique.

Microvascular Decompression for Trigeminal Neuralgia: A Prospective, Multicenter Study

BACKGROUND

Microvascular decompression (MVD) is the most effective procedure for the long-term management of trigeminal neuralgia (TGN). However, retrospective and single-center studies are inherently biased, and there are currently no prospective, multicenter studies.

OBJECTIVE

To evaluate the short- and long-term outcomes and complications in patients with TGN who underwent MVD at specialized Japanese institutions.

METHODS

We enrolled patients with TGN who underwent MVD between April 2012 and March 2015. We recorded their facial pain grade and complications at 7 d (short term), 1 yr (mid-term), and 3 yr (long term) postoperatively.

RESULTS

There were 166 patients, comprising 60 men and 106 women (mean age 62.7 yr). Furthermore, 105 patients were aged over 60 yr. We conducted neuromonitoring in 84.3% of the cases. The complete pain relief, mortality, and complication rates at the short-term follow-up were 78.9%, 0%, and 16.3%, respectively. Overall, 155 patients (93.4%) completed the long-term follow-up, with the complete pain relief and complication rates of 80.0% and 5.2%, respectively.

CONCLUSION

In the hands of experienced neurosurgeons, MVD for TGN can achieve high long-term curative effects. In addition, complications are uncommon and usually transient. Our results indicate that MVD is an effective and safe treatment for patients with TGN, including elderly patients.

Case of de novo cerebral microbleeds in ischemic-type pediatric moyamoya disease

Background:

Studies on pediatric patients with moyamoya disease who presented with de novo cerebral microbleeds (CMBs) are extremely rare.

Case Description:

Herein, we report a 7-year-old boy with moyamoya disease who had de novo CMBs during treatment. He presented with transient left-side motor weakness and was diagnosed with moyamoya disease. He underwent revascularization surgery on the right cerebral hemisphere. Six months after the surgery, he presented with transient right-side motor weakness and MRA revealed progression of stenosis in the left middle cerebral artery. After another 3 months, three de novo CMBs were identified. He underwent revascularization surgery on the left side. The symptom disappeared completely after surgery and no additional de novo CMBs were identified 1 year after surgery.

Conclusion:

This is the first report on de novo CMBs in pediatric patients. Although the significance of de novo CMBs in pediatric patients is completely unknown, attention should be paid to not only ischemic stroke but also hemorrhagic stroke. Although the short-term course is good in the current case, follow-up period is too short to assess for rebleeding and long-term follow-up is still important. Further, more cases should be collected.

Prospective, Multicenter Clinical Study of Microvascular Decompression for Hemifacial Spasm

BACKGROUND

Microvascular decompression (MVD) is the most effective procedure for hemifacial spasm (HFS). MVD results from nonspecialized or low-volume institutes are not always reliable. Most studies on MVD for HFS are retrospective and single centered; to the best of our knowledge, no prospective, multicenter studies exist.

OBJECTIVE

To evaluate short- and long-term outcomes and complications in patients who underwent MVD for HFS in specialized Japanese institutions, in this multicenter, prospective, cohort study.

METHODS

Included patients had undergone MVD for HFS in study centers between April 2012 and March 2015. Patients' postoperative grade of involuntary movements and complications were recorded postoperatively at 7 d (short-term) and at 1 (mid-term) and 3 (long-term) yr.

RESULTS

A total of 486 patients (150 men, 336 women; mean age 53.9 yr with 181 patients over 60 yr) were enrolled during the study period. Neuromonitoring was used in 96.3% of the cases. The complete cure rate of symptom relief, mortality rate, and complication rate at short-term follow-up were 70.6%, 0%, and 15%, respectively. The long-term follow-up was completed by 463 patients (95.3%); the complete cure rate of symptom relief and complication rate were 87.1% and 3.0%, respectively.

CONCLUSION

Our study revealed that under expert guidance and intraoperative neuromonitoring, the long-term curative effect rate of MVD for HFS is high, while complications are uncommon and usually transient. Our results indicate that MVD is an effective and safe treatment for patients with HFS, including elderly patients.

A case of pediatric moyamoya disease with severe cerebral vasospasm and delayed cerebral infarction following an intraventricular hemorrhage

Reports on patients with moyamoya disease presenting cerebral ischemic complications after the onset of intraventricular hemorrhage (IVH) and/or intracerebral hemorrhage (ICH) are limited. Herein, we report a case of a 7-year-old girl with moyamoya disease with severe cerebral vasospasm and delayed cerebral infarction following an IVH. Although the case is rare, the potential for vasospasm-induced cerebral infarction should be carefully considered and thus, intensive treatment should be immediately initiated.

SURG-24. NOVEL MALLEABLE FORCIPES FOR ENDOSCOPIC ASSISTED TECHNIQUE IN PEDIATRIC BRAIN TUMORS

Recent advances in optical devices and surgical instruments have been applied to neurosurgery. Even with modifications, one of the most serious risks is injury of neuronal and vascular structure caused by operation of surgical instruments in a narrow surgical field. Fixed instruments are not practical for pediatric brain tumor surgeries because the length of the curved or angled tip portion is limited because of the narrow entrance. We developed a novel malleable forceps to resolve the difficulties related to microsurgical procedures. The malleable forceps has two shafts with a sharp cup at the tip. The entire forceps was made of stainless steel, with a silver and nickel alloy inserted between 10 and 40 mm from the tip. In the alloy part, the surgeon can flex the forceps freely using a special cylinder. The special cylinder is useful to prevent from slipping of the cups of tip. The maximum angle that can be bent is 70 degrees vertically. We also developed a monoshaft malleable forceps. We used these flexible forcipes in the case of various pediatric brain tumors including craniopharyngioma. We performed tumor resection by anterior interhemispheric trans-lamina terminalis approach. After procedure of tumor resection using microscope, endoscope inserted around the pituitary stalk. The piece of calcified tumor could be easily removed without any complications. These forcipes can be deformed to an appropriate angle and can be applied to various cases, especially pediatric brain tumors.

Influence of Microcatheter Position on First-pass Success of Thrombectomy for Acute Ischemic Stroke

OBJECTIVE

In acute ischemic stroke, patient outcomes can be improved by first-pass successful recanalization of the occluded vessel. This study investigated whether microcatheter position could influence the success of first-pass recanalization.

METHODS

We retrospectively analyzed 59 consecutive acute ischemic stroke patients who underwent intra-arterial thrombectomy with stent retrievers for middle cerebral artery (M1) occlusion. Angiography findings obtained via the first pass of the microcatheter were analyzed. The microcatheter was considered to be inserted into M2 segments that gave rise to parietal arteries (M2P) if the anterior or posterior parietal artery was observed. Recanalization results were compared between patients with and without microcatheter insertion into M2P. The angle and diameter of vessels were measured using post-procedural magnetic resonance angiography.

RESULTS

The rate of first-pass successful recanalization (modified thrombolysis in cerebral infarction score of ≥2b) was significantly higher in patients with microcatheter insertion into M2P than in those without (56% vs. 22%, P = 0.016). The number of passes was lower in patients with first-pass microcatheter insertion into M2P than in those without (1.8 ± 1.0 vs. 2.5 ± 1.5, P = 0.05). The mean diameter of M2P was significantly larger than that of the other M2 (1.9 ± 0.6 mm vs. 1.7 ± 0.5 mm, P = 0.035). The M1/M2P angle was significantly smaller than that between M1 and the other M2. (49° ± 32° vs. 67° ± 31°, P = 0.006).

CONCLUSIONS

First-pass microcatheter insertion into M2P may contribute to fast successful recanalization in patients with M1 occlusion who undergo intra-arterial thrombectomy using stent retrievers.

Diagnosis and clinical course of ocular ischemic syndrome with retinal vascular abnormalities due to unilateral ocular artery and internal carotid artery stenosis in a child with neurofibromatosis type 1: a case report

Background

Neurofibromatosis type 1 (NF1) is a hereditary disease that causes neurofibromas generally, but it has been reported to sometimes be associated with various forms of blood vessel stenosis, occlusion and vascular abnormalities of unknown mechanism. However, a symptomatic case with simultaneous ophthalmic artery stenosis and internal carotid artery stenosis is an extremely rare pathogenesis in a child with NF1. In this report, we performed the diagnosis and observation using various imaging modalities for this rare pediatric case.

Case presentation

A 6-year-old girl diagnosed with NF1 presented with gradual visual loss in the right eye. Best corrected visual acuity (BCVA) was 20/40 OD and the intraocular pressure (IOP) was normal in both eyes. Retinal vascular abnormalities with tortuous vessels and optic disc pallor were observed in the right fundus. Widefield fluorescein angiography revealed multiple sites of neovascularization and a large non-perfusion area in the peripheral retina. Optical coherence tomography angiography showed retinal vascular abnormalities in the right eye and revealed differences in inner retinal thickness and blood flow signal between the left and right eyes. Laser speckle flowgraphy showed that chorioretinal blood flow was significantly decreased in the right eye. Cerebral angiography revealed the right ophthalmic artery was significantly narrowed throughout. In addition, Magnetic resonance angiography revealed that the right internal carotid artery was significantly narrowed in the ophthalmic segment. We diagnosed ophthalmic artery and internal carotid artery stenosis with retinal vascular abnormalities and ocular ischemic syndrome in NF1. Because IOP increased to 35 mmHg, due to neovascular glaucoma in addition to mild vitreous hemorrhage occurred, panretinal photocoagulation was performed after intravitreal bevacizumab injection. After treatments, IOP normalized, but BCVA decreased to 20/100 OD. Arterial spin labeling showed normal cerebral blood flow. The patient is currently being carefully monitored.

Conclusions

We have described the diagnosis and treatment of ocular ischemic syndrome due to multiple arteries stenosis in a child with NF 1. Utilization of various imaging modalities was helpful in diagnosing the complicated pathogenesis. However, since direct intervention by neurosurgery is not possible in this case, it is expected that treatment will be extremely difficult in the future.

Study of the Anatomical Features of the Offending Arteries Involved in Glossopharyngeal Neuralgia

BACKGROUND

The anatomic features of the posterior inferior cerebellar arteries (PICAs) and the anterior inferior cerebellar arteries (AICAs) as offending arteries involved in glossopharyngeal neuralgia (GPN) are important to dictate the best surgical approach.

OBJECTIVE

To study and classify the anatomic features of the offending arteries.

METHODS

All clinical data and surgical videos from 18 GPN cases that were surgically treated during the past 10 yr were retrospectively reviewed.

RESULTS

Among these 18 patients, the offending arteries involved were the PICA in 12 (66.7%), AICA in 4 (22.2%), and both PICA and AICA in 2 (11.1%). The PICA were then classified into the following groups based on their anatomic features: type I: the PICA formed an upward loop at the level of the glossopharyngeal nerve and passed between the glossopharyngeal and vestibulocochlear nerves; type II: the PICA formed an upward loop at the level of the glossopharyngeal nerve and passed between the glossopharyngeal and vagus nerves or between the rootlets of the vagus nerve; and type III: the PICA passed between the glossopharyngeal and vestibulocochlear nerves without forming a loop. The AICA had only one running pattern.

CONCLUSION

The offending arteries involved in GPN, mainly the PICA and/or AICA, were classified into 4 different types based on their anatomic features.

Hemorrhagic stroke associated with essential thrombocythemia: Case report and literature review

Hemorrhagic stroke associated with essential thrombocythemia (ET) is very infrequent. Herein, we report a case of a 33-year-old woman with a 2-year history of ET who developed intracerebral and subarachnoid hemorrhage. Angiography demonstrated severe vessel irregularity in the bilateral cerebral arteries. Molecular genetic testing revealed a calreticulin mutation. To our knowledge, hemorrhagic stroke has been reported in only six other patients with ET, and this is the first report of hemorrhagic stroke in an ET patient with a calreticulin mutation. We review the current literature and discuss the possible underlying mechanisms.

Boron Neutron Capture Therapy and Photodynamic Therapy for High-Grade Meningiomas

Meningiomas are the most common type of intracranial brain tumors in adults. The majority of meningiomas are benign with a low risk of recurrence after resection. However, meningiomas defined as grades II or III, according to the 2016 World Health Organization (WHO) classification, termed high-grade meningiomas, frequently recur, even after gross total resection with or without adjuvant radiotherapy. Boron neutron capture therapy (BNCT) and photodynamic therapy (PDT) are novel treatment modalities for malignant brain tumors, represented by glioblastomas. Although BNCT is based on a nuclear reaction and PDT uses a photochemical reaction, both of these therapies result in cellular damage to only the tumor cells. The aim of this literature review is to investigate the possibility and efficacy of BNCT and PDT as novel treatment modalities for high-grade meningiomas. The present review was conducted by searching PubMed and Scopus databases. The search was conducted in December 2019. Early clinical studies of BNCT have demonstrated activity for high-grade meningiomas, and a phase II clinical trial is in progress in Japan. As for PDT, studies have investigated the effect of PDT in malignant meningioma cell lines to establish PDT as a treatment for malignant meningiomas. Further laboratory research combined with proper controlled trials investigating the effects of these therapies is warranted.

Association between Pericytes in Intraplaque Neovessels and Magnetic Resonance Angiography Findings

(1) Background: Pericytes are involved in intraplaque neovascularization of advanced and complicated atherosclerotic lesions. However, the role of pericytes in human carotid plaques is unclear. An unstable carotid plaque that shows high-intensity signals on time-of-flight (TOF) magnetic resonance angiography (MRA) is often a cause of ischemic stroke. The aim of the present study is to examine the relationship between the pericytes in intraplaque neovessels and MRA findings. (2) Methods: A total of 46 patients with 49 carotid artery stenoses who underwent carotid endarterectomy at our hospitals were enrolled. The patients with carotid plaques that were histopathologically evaluated were retrospectively analyzed. Intraplaque hemorrhage was evaluated using glycophorin A staining, and intraplaque neovessels were evaluated using CD34 (Cluster of differentiation) stain as an endothelial cell marker or NG2 (Neuron-glial antigen 2) and CD146 stains as pericyte markers. Additionally, the relationships between the TOF-MRA findings and the carotid plaque pathologies were evaluated. (3) Results: Of the 49 stenoses, 28 had high-intensity signals (TOF-HIS group) and 21 had iso-intensity signals (TOF-IIS group) on TOF-MRA. The density of the CD34-positive neovessels was equivalent in both groups. However, the NG2- and CD146-positive neovessels had significantly higher densities in the TOF-HIS group than in the TOF-IIS group. (4) Conclusion: The presence of a high-intensity signal on TOF-MRA in carotid plaques was associated with intraplaque hemorrhage and few pericytes in intraplaque neovessels. These findings may contribute to the development of new therapeutic strategies focusing on pericytes.

BMP4 induces asymmetric cell division in human glioma stem-like cells

Glioblastoma (GBM) is a malignant tumor with a high recurrence rate and has very poor prognosis in humans. The median survival is still <2 years. Therefore, a new treatment strategy should be established. Recently, this cancer has been thought to be heterogeneous, consisting of cancer stem cells (CSCs) that are self-renewable, multipotent, and treatment resistant. So various strategies targeting glioma stem-like cells (GSCs) have been investigated. This study focused on strategies targeting GSCs through the induction of differentiation using bone morphogenetic protein 4 (BMP4). The expression of CD133, a cancer stem cell marker, under BMP4 treatment in GSCs was examined using flow cytometry, western blotting, and quantitative PCR. Immunofluorescent staining of GSCs was also performed to examine the type of cell division: asymmetric cell division (ACD) or symmetric cell division (SCD). We obtained the following results. The BMP4 treatment caused downregulation of CD133 expression. Moreover, it induced ACD in GSCs. While the ACD ratio was 23% without BMP4 treatment, it was 38% with BMP4 treatment (P=0.004). Furthermore, the tumor sphere assay demonstrated that BMP4 suppresses self-renewal ability. In conclusion, these findings may provide a new perspective on how BMP4 treatment reduces the tumorigenicity of GSCs.

NI-18 INVASIONS OF WHITE MATTER AS A PROGNOSTIC FACTOR IN LOW GRADE GLIOMAS

INTRODUCTION

Gliomatosis cerebri (GC), which was characterized by widespread infiltration of the brain involving three lobes, was deleted in the 2016 WHO classification. However, it is known that gliomas with GC growth pattern have a poor prognosis even in low histological grading. In this study, we focused on tumor invasion into white matter fibers. We analyzed the MRI findings focusing on white matter fibers and compared in patients with histologically proven low grade gliomas (LGGs) with GC pattern and localized LGGs.

METHOD

The patients can be classified into four groups according to the range of tumor invasion in T2-weighted image as follows: group 1, more than 3 lobes (n=6); group 2, 1 or 2 lobes infiltrate the basal ganglia (n=5); group 3, multicentric (n=2) and group 4 (n=12), localized. In reference to the human brain white matter atlas, the infiltration to the major white matter fibers (uncinate fasciculus, genu &splenium of corpus callosum, inferior fronto-occipital fasciculus, superior& inferior longitudinal fasciculus) was examined.

RESULTS

Twenty-five patients (median 39.5 years) were included in the study. Of these, 20 patients were histologically diagnosed with diffuse astrocytomas, and 5 patients with oligodendrogliomas. The infiltrations into ifo, slf, and ilf of white matter fibers were a poor prognostic factor. The number of infiltrating white matter fibers correlated significantly with the Kaplan-Meier survival curve.

CONCLUSIONS

The 2016 WHO classification defines diagnostic entities by combining molecular and histological information and remove GC as a distinct glioma entity. LGGs with GC pattern should be considered to be detected in different types of histologically and molecularly defined gliomas. As the patient numbers analyzed here were small, and larger series reproducing these results would be desirable. MRI findings particularly focusing on infiltration of LGGs into white matter fibers might be important to estimate the prognosis of patients.

GENE-14. BMP4 INDUCES TO ASYMMETRIC CELL DIVISION IN HUMAN GLIOMA STEM-LIKE CELLS

Glioblastoma (GBM) is one of the human malignant tumors with a high recurrence rate and the poorest prognosis. Therefore, a new treatment strategy is required. It has also come to be thought that cancer is a heterogeneous, which composes of cancer stem cells (CSCs), which have self-renewal ability, multipotency and treatment resistance. Although various strategies targeting glioma stem-like cells (GSCs) have been studied, a median survival remains to be less than 2 years. In this study, we focused on strategies targeting GSCs through induction of differentiation using BMP4. We examined the expression of CD133, a cancer stem cell marker, under BMP4-treatment in GSCs using flowcytometry analysis, western blotting and qPCR. We also examined immunofluorescent staining of GSCs to study cell division. The treatment of BMP4 caused downregulation of CD133 expression in GSCs. In addition, BMP4-treatment induced to asymmetric cell division in GSCs. Tumor sphere assay showed that BMP4 suppresses self-renewal ability. These findings may provide a new perspective how BMP4 reduces the tumorigenicity of GSCs.

Significance of simulated conventional images on dual energy CT after endovascular treatment for ischemic stroke

BACKGROUND AND PURPOSE

CT scans often reveal post-interventional cerebral hyperdensities (PCHDs) immediately after intra-arterial thrombectomy (IAT) for ischemic stroke. Dual energy CT (DE-CT) can indicate whether PCHDs are caused by hemorrhage or iodinated contrast. Hyperdense lesions, detected on DE-CT with the use of iodinated contrast, could be associated with delayed hemorrhagic transformation and poor outcome. However, the quantitative indicators in DE-CT for predicting delayed hemorrhagic transformation remain unclear. We assessed such indicators for predicting delayed hemorrhagic transformation.

MATERIAL AND METHODS

We retrospectively analyzed 52 consecutive acute ischemic stroke patients who underwent IAT. Simulated conventional CT (sCCT) images were obtained immediately after a DE-CT scan. Virtual, unenhanced, non-contrast (VNC) imaging was performed after reconstruction. Hounsfield units (HU) of the infarct areas observed on the sCCT were measured. The association of HU on sCCT with hemorrhage on VNC and delayed parenchymal hemorrhage (PH) was evaluated.

RESULTS

The HU of sCCT with hemorrhage on VNC was significantly higher than without it (377.9±385 HU vs 83.5±37.9 HU; P<0.0001). The cut-off index was 80 HU, which displayed 100% sensitivity, 63.8% specificity, 22.3% positive predictive value, and 100% negative predictive value (P=0.0001, area under the curve (AUC)=0.89). The HU with delayed PH was substantially higher than without it (250.8±382.2 HU vs 93.7±64.8 HU; P=0.01). The cut-off index was 78 HU, which showed 100% sensitivity, 61% specificity, 25% positive predictive value, and 100% negative predictive value (P=0.049, AUC=0.76).

CONCLUSION

sCCT images on DE-CT are useful for excluding intracerebral hemorrhage and delayed PH.

Status epilepticus induced by treatment with dopamine agonist therapy for giant prolactinoma: a case report

Background

Dopamine agonists are the standard first-line medical therapy for prolactinoma. We report a rare case of giant prolactinoma with a first epileptic seizure due to rapid reduction of the tumor as a complication of dopamine agonist therapy.

Case presentation

A 27-year-old Japanese man presented to our institution with a history of visual disturbance for 1 year and general fatigue for 3 months. Magnetic resonance imaging showed a tumor that arose from the pituitary and extended to the bilateral anterior skull base, the clivus, and the cavernous sinus, with compression of the optic chiasm and the bilateral frontal and temporal lobes. On the basis of the patient’s serum concentration of prolactin, we diagnosed a prolactinoma and started dopamine agonist therapy with cabergoline. The patient had a general seizure immediately after starting dopamine agonist therapy and required general anesthetic treatment following the rapid reduction of the tumor. We speculated that the rapid reduction of the tumor resulted in the retraction of the surrounding brain structure, and the epileptic seizure was then induced by dopamine agonist therapy.

Conclusions

We report a rare case of giant prolactinoma with a first epileptic seizure immediately after the initiation of dopamine agonist therapy. Clinicians need to be aware that the rapid reduction of a giant prolactinoma by dopamine agonist therapy may cause an epileptic seizure.

Extensive spinal epidural immature teratoma in an infant: case report

Here, the authors present an extremely rare case of an extensive spinal epidural teratoma (SET) in an infant and provide a review of the cases in the literature. In this report, the authors focused on the clinical manifestation and management of extensive SET. A 64-day-old girl presented with severe dyspnea and paraparesis caused by a large thoracic mass. Imaging studies revealed that the mass originated from the epidural space of the thoracic spine and extended from C7 to L1. The tumor extended bilaterally through the intervertebral foramina and formed a large posterior mediastinal mass. The tumor was partially resected via laminotomy after an emergency thoracotomy. The remnant grade I immature teratoma grew rapidly. After a re-laminotomy and bilateral thoracotomy, the residual tumor stopped growing. However, the patient's paraparesis improved very little, and her scoliosis progressed gradually. Therefore, SET should be included in the differential diagnosis when an infant patient with paraparesis of the lower extremities is encountered. Timely diagnosis, aggressive treatment, and close monitoring are of critical importance to successful recovery in such patients.

Possible involvement of pericytes in intraplaque hemorrhage of carotid artery stenosis

OBJECTIVEIntraplaque hemorrhage (IPH) is most often caused by the rupture of neovessels; however, the factors of intraplaque neovessel vulnerability remain unclear. In this study, the authors focused on pericytes and aimed to investigate the relationship between IPH and pericytes.METHODSThe authors retrospectively analyzed the medical records of all patients with carotid artery stenoses who had undergone carotid endarterectomy at their hospitals between August 2008 and March 2016. Patients with carotid plaques that could be evaluated histopathologically were eligible for study inclusion. Intraplaque hemorrhage was analyzed using glycophorin A staining, and patients were divided into the following 2 groups based on the extent of granular staining: high IPH (positive staining area > 10%) and low IPH (positive staining area ≤ 10%). In addition, intraplaque neovessels were immunohistochemically evaluated using antibodies to CD34 as an endothelial cell marker or antibodies to NG2 and CD146 as pericyte markers. The relationship between IPH and pathology for intraplaque neovessels was investigated.RESULTSSeventy of 126 consecutive carotid stenoses were excluded due to the lack of a specimen for histopathological evaluation; therefore, 53 patients with 56 carotid artery stenoses were eligible for study inclusion. Among the 56 stenoses, 37 lesions had high IPH and 19 had low IPH. The number of CD34-positive neovessels was equivalent between the two groups. However, the densities of NG2- and CD146-positive neovessels were significantly lower in the high IPH group than in the low IPH group (5.7 ± 0.5 vs. 17.1 ± 2.4, p < 0.0001; 6.6 ± 0.8 vs. 18.4 ± 2.5, p < 0.0001, respectively).CONCLUSIONSPlaques with high IPH are associated with fewer pericytes in the intraplaque neovessels. This finding may help in the development of novel therapeutic strategies targeting pericytes.

Dural arteriovenous fistula manifesting as pontine hemorrhage at the craniocervical junction

Craniocervical junction (CCJ) dural arteriovenous fistula (DAVF) manifesting as intracerebral hemorrhage is extremely rare. We report the first case of CCJ-DAVF manifesting as pontine hemorrhage. A 69-year-old male presented with a pontine hemorrhage manifesting as a sudden onset of right hemiparesis and dysarthria. Digital subtraction angiography revealed a CCJ-DAVF fed by the meningeal branches of the right vertebral artery. The patient underwent surgical ligation of the cerebral draining veins to prevent re-bleeding. The postoperative course was uneventful. The patient had no neurological deficit after 1 month rehabilitation.

[A Rare Case of Cerebellar Hemangioblastoma Causing Taste Disorder]

Taste(gustation)is one of the five senses, and comprises the types: sweet, bitter, salty, sour, and umami. Taste disorders, such as dysgeusia and parageusia, are classified into 2 types: those with peripheral origin and those with central origin. The peripheral origin-type taste disorder is caused by zinc deficiency, mouth dryness, a side effect of radiotherapy or complication of systemic diseases such as, diabetes, hepatopathy, and nephropathy. The central origin-type taste disorder is reported to be caused due to demyelinating disease, pontine hemorrhage, pontine infarction, and thalamic infarction; it is very rarely caused by a brain tumor. We surgically treated a 69-year-old man with cerebellar hemangioblastoma who had developed taste disorder. The tumor compressed the solitary nucleus, which includes the taste tract in the central nervous system. On removal of the tumor, the taste disorder gradually improved.

Brain metastasis from primary peritoneal carcinoma: Case report and literature review

Here, we describe a patient with primary peritoneal carcinoma (PPC) who developed a late, solitary brain metastasis. It is a case of a 68-year-old female presented with a 1-month history of progressive gait disturbance who had undergone a surgical resection of PPC five years prior, followed by adjuvant chemotherapy. An MRI revealed a 4.6cm mass lesion in her right cerebellum. The patient underwent total removal of the tumour. The histopathology was consistent with a brain metastasis due to PPC. This condition is a rare malignancy of peritoneum, and only six cases of brain metastasis have been reported in PPC patients to date. Due to the prolongation of survival resulting from advanced chemotherapy for PPC, more patients will live long enough to develop brain metastases.

Typical Symptoms of Normal-Pressure Hydrocephalus Caused by Choroid Plexus Papilloma in the Cerebellopontine Angle

BACKGROUND

Choroid plexus papillomas (CPPs) are rare benign intracranial tumors. We report a rare case of CPP manifesting with typical symptoms of normal-pressure hydrocephalus rather than obstructive hydrocephalus.

CASE DESCRIPTION

A 45-year-old woman presented with a 6-year history of headache and typical symptoms of normal-pressure hydrocephalus, including gait disturbance, urinary incontinence, and cognitive dysfunction, in addition to the more common symptoms of CPP, such as lower cranial nerve dysfunctions and ataxia. The CPP arose from the right lateral recess of the fourth ventricle and extended to the cerebellopontine angle. Magnetic resonance imaging did not show any radiographic evidence of obstruction of aqueduct, foramen of Magendie, or foramen of Luschka on the contralateral side. We speculated that hydrocephalus was associated with cerebrospinal fluid overproduction by the CPP originating from the choroid plexus of the lateral recess and extending laterally into the cerebellomedullary fissure (CMF). Surgical excision was performed with a trans-CMF approach. The symptoms of normal-pressure hydrocephalus disappeared. In addition to improved clinical symptoms, radiographic findings showed mitigation of ventricular dilatation.

CONCLUSIONS

The hydrocephalus was of a communicating type and caused by CSF overproduction. The lateral route of the trans-CMF approach is useful for the dissection of tumors that extend into the unilateral cerebellomedullary cistern through the CMF. This approach not only enables sufficient exposure for resection but also avoids damage to the surrounding structures.

[Two Cases of Ruptured Cerebral Aneurysm Complicated with Delayed Coil Protrusion after Coil Embolization]

We report two cases of delayed coil protrusion after coil embolization for ruptured cerebral aneurysms. Case 1:An 82-year-old woman with a subarachnoid hemorrhage due to a ruptured small anterior communicating artery aneurysm underwent successful coil embolization. Eighteen days after the procedure, coil protrusion from the aneurysm into the right anterior cerebral artery was observed without any symptoms. Further coil protrusion did not develop after 28 days. Case 2:A 78-year-old woman with a subarachnoid hemorrhage due to a ruptured small left middle cerebral artery aneurysm underwent successful coil embolization. Twenty days after the procedure, coil protrusion from the aneurysm into the left middle cerebral artery was observed, with a transient ischemic attack. Further coil protrusion did not develop. Both patients recovered with antithrombotic treatment. Even though delayed coil protrusion after coil embolization is rare, it should be recognized as a long-term complication of coil embolization for cerebral aneurysms.

Carotid artery stenosis with a high-intensity signal plaque on time-of-flight magnetic resonance angiography and association with evidence of intraplaque hypoxia

OBJECTIVE

Hypoxia induces angiogenesis and plays a major role in the progression of carotid plaques. During carotid intervention, plaques with high-intensity signals on time-of-flight (TOF) magnetic resonance angiography (MRA) often cause ischemic stroke and embolic complications. However, the role of intraplaque hypoxia before carotid endarterectomy (CEA) and carotid artery stenting is not presently understood. In this study the authors aimed to investigate the relationship between intraplaque hypoxia and MRA findings.

METHODS

Nineteen consecutive patients with 20 carotid artery stenoses who underwent CEA at Saga University Hospital between August 2008 and December 2014 were enrolled in the study. The expressions of hypoxia-inducible transcription factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were analyzed by immunohistochemical analysis. In addition, the relationship between the findings on TOF MRA and pathology for the carotid plaques was analyzed.

RESULTS

High-intensity plaques on TOF MRA showed higher expression levels of HIF-1α (p = 0.015) and VEGF (p = 0.007) compared with isointensity plaques. The rate of intraplaque hemorrhage (IPH) on TOF MRA was also significantly higher in the high-intensity plaques than in the isointensity plaques (p = 0.024). Finally, the mean number of neovessels was significantly higher in those without plaque hemorrhage than in those with plaque hemorrhage (p = 0.010).

CONCLUSIONS

Plaques with high-intensity signals on TOF MRA were associated with IPH and evidence of intraplaque hypoxia. This fact may represent an opportunity to establish novel therapeutic agents targeting intraplaque hypoxia.

Utility of intraoperative fetal heart rate monitoring for cerebral arteriovenous malformation surgery during pregnancy

We report two methods of intraoperative fetal heart rate (FHR) monitoring in cases of cerebral arteriovenous malformation surgery during pregnancy. In one case in her third trimester, cardiotocography was used. In another case in her second trimester, ultrasound sonography was used, with a transesophageal echo probe attached to her lower abdomen. Especially, the transesophageal echo probe was useful because of the advantages of being flexible and easy to attach to the mother's lower abdomen comparing with the usual doppler ultrasound probe. In both cases, the surgery was successfully performed and FHR was monitored safely and stably. The use of intraoperative FHR monitoring provides information about the influence of induced maternal hypotension and unexpected bleeding on fetus during surgery. These monitoring techniques would be especially emphasized in cerebrovascular surgery for the safe management of both mother and fetus.

Importance of awareness of the rhomboid lip in microvascular decompression surgery for hemifacial spasm

OBJECT

The authors adopted the infrafloccular approach for microvascular decompression (MVD) surgery to treat hemifacial spasm (HFS). The inferior portion of the flocculus is retracted to observe the root exit zone of cranial nerve (CN) VII between CN IX and the flocculus. During the procedure, the rhomboid lip, a sheetlike layer of neural tissue forming the lateral recess of the fourth ventricle, is sometimes encountered. The existence of the rhomboid lip in cases of HFS was reviewed to determine the importance of the structure during MVD surgery.

METHODS

Preoperative imaging and intraoperative observations in 34 consecutive cases of HFS treated in the period from October 2008 through September 2011 were used to assess the frequency of encountering the rhomboid lip.

RESULTS

The rhomboid lip was observed during MVD surgery in 9 (26.5%) of the 34 cases but had been demonstrated on preoperative MR images in only 3 cases (8.8%). On T2-weighted images, it appeared as a high-intensity nonstructural area on the ventral side of the flocculus and continued into the fourth ventricle via the foramen of Luschka.

CONCLUSIONS

A large rhomboid lip presents an impediment to MVD surgery in a significant minority of patients with HFS. It is seldom observed on preoperative MR images. Proper dissection of the rhomboid lip away from the arachnoid membrane and/or the lower CNs during MVD surgery provides good visualization of the root exit zone of CN VII and reduces injury of CNs IX and X, avoiding postoperative deficits like dysphagia.

Cerebral blood flow and metabolism of hyperperfusion after cerebral revascularization in patients with moyamoya disease

In moyamoya disease (MMD), surgical revascularization may be complicated with postoperative hyperperfusion. We analyzed cerebral perfusion and metabolism using positron emission tomography (PET) or single-photon emission computed tomography (SPECT) before and after bypass surgery on 42 sides of 34 adult patients with MMD. In seven cases (16.7%) with symptomatic hyperperfusion, diagnosed by qualitative (123)I-iodoamphetamine (IMP) SPECT, a subsequent PET study during postoperative subacute stages revealed significantly increased cerebral blood flow (CBF) from 34.1 ± 8.2 to 74.3 ± 12.8 mL/100 g per minute (P<0.01), a persistent increase in cerebral blood volume (CBV) from 5.77 ± 1.67 to 7.01 ± 1.44 mL/100 g and a significant decrease in oxygen extraction fraction (OEF) from 0.61 ± 0.09 to 0.40 ± 0.08 (P<0.01). Mean absolute CBF values during symptomatic hyperperfusion were more than the normal control +2 standard deviations, the predefined criteria of PET. Interestingly, two patients with markedly increased cerebral metabolic rate of oxygen (CMRO(2)) at hyperperfusion were complicated with postoperative seizure. Among preoperative PET parameters, increased OEF was the only significant risk factor for symptomatic hyperperfusion (P<0.05). This study revealed that symptomatic hyperperfusion in MMD is characterized by temporary increases in CBF >100% over preoperative values caused by prolonged recovery of increased CBV.

Transcondylar fossa (supracondylar transjugular tubercle) approach: anatomic basis for the approach, surgical procedures, and surgical experience

The authors clarify the anatomic basis and the usefulness of the transcondylar fossa approach (T-C-F A), in which the posterior portion of the jugular tubercle is removed extradurally through the condylar fossa with the atlanto-occipital joint intact. The authors first performed an anatomic study to identify the area to be removed using cadaveric specimens and then applied the T-C-F A to foramen magnum surgeries. The surgeries included clipping a vertebral artery-posterior inferior cerebellar artery aneurysm in 11 cases, microvascular decompression for glossopharyngeal neuralgia in 15 cases, and removing intradural foramen magnum tumors in 17 cases. Only the condylar fossa was removed, but the approach offered very good visualization of the lateral part of the foramen magnum and sufficient working space. These surgeries were performed safely without major complications. This skull base approach is minimally invasive and is not difficult. Therefore, it can be a standard approach for accessing intradural lesions of the foramen magnum. It can be combined with the transcerebellomedullary fissure approach from the lateral side and can also be easily changed to the transcondylar approach, if necessary.

Meningioma manifesting as cerebral infarction

A previously healthy 31-year-old man presented with an extremely rare case of small meningioma associated with cerebral infarction preceded by recurrent transient ischemic attacks manifesting as a 3-day history of recurrent and transient weakness of the left lower limb lasting several minutes for each episode. The symptoms became persistent and complete on the following day. Magnetic resonance imaging revealed acute cerebral infarction in the right frontal lobe and a 20 mm diameter tumor in the planum sphenoidale encasing the right anterior cerebral artery. Cerebral angiography demonstrated occlusion of the right A(2) portion. The patient underwent surgery and the tumor was gross totally removed. The histological diagnosis was meningothelial meningioma. Cases of meningioma causing cerebral infarction are very rare, but the possibility should be considered even if the tumor is small.

Microvascular decompression for glossopharyngeal neuralgia through the transcondylar fossa (supracondylar transjugular tubercle) approach

OBJECTIVE

Our surgical results were reviewed to clarify the cause of glossopharyngeal neuralgia (GPN) and the effects of the microvascular decompression (MVD) procedure.

METHODS

Fourteen cases of idiopathic GPN were operated on through the transcondylar fossa (supracondylar transjugular tubercle) approach. Their clinical data and operative records were retrospectively reviewed.

RESULTS

In every case, vascular compression on the glossopharyngeal nerve was found and MVD was performed without any major complications. In 13 of the 14 cases the neuralgia completely disappeared postoperatively. Recurrence of pain was found in 1 case. Offending vessels were the posterior inferior cerebellar artery (PICA) in 10 cases, the anterior inferior cerebellar artery (AICA) in 2 cases, and both arteries in 2 cases. In 10 of the 14 cases, the high-origin PICA formed an upward loop between the glossopharyngeal and vagus nerves, compressing the glossopharyngeal nerve upward. In those cases, the PICA was transposed and fixed to the dura mater by the stitched sling retraction technique, and MVD was very effective.

CONCLUSION

The offending artery was the PICA in most cases. MVD is expected to be very effective, especially when the radiological images show the following 3 findings: 1) high-origin PICA, 2) the PICA making an upward loop, and 3) the PICA coursing the supraolivary fossette. The transcondylar fossa approach is suitable for transposing the PICA by the stitched sling retraction technique, and provides sufficient surgical results.

Adhesion of rhomboid lip to lower cranial nerves as special consideration in microvascular decompression for hemifacial spasm: Report of two cases

BACKGROUND

Although the rhomboid lip is a well-known structure constructing the foramen of Luschka, less attention has been directed to the structure for posterior fossa microsurgeries. The authors report two cases of the hemifacial spasm (HFS) with a large rhomboid lip, focusing on the importance of the structure during microvascular decompression.

CASE DESCRIPTION

A 59-year-old female presenting with left HFS was admitted to our hospital. A preoperative magnetic resonance image demonstrated an offending artery at the root exit zone of the VII nerve. The patient underwent microvascular decompression through the lateral suboccipital approach. The intraoperative findings showed that a large rhomboid lip adhered to the IX and X cranial nerves and prevented the exposure of the root exit zone of the VII cranial nerve. The rhomboid lip was meticulously separated from the cranial nerves so that the choroid plexus of the foramen of Luschka and the rhomboid lip could be safely lifted with a spatula, and the offending artery was successfully detached from the root exit zone. In another case of a 60-year-old male, the rhomboid lip was so large that it needed to be incised before separating it from the lower cranial nerves. In each case, the HFS was resolved following surgery without any new deficits.

CONCLUSION

The large rhomboid lip adhering to the cranial nerves should be given more attention in the posterior fossa surgeries and should be managed based on the microsurgical anatomy for preventing unexpected lower cranial nerve deficit.

Intracranial pial single-channel arteriovenous fistula presenting with significant brain edema

The authors report a rare case of pial single-channel arteriovenous fistula presenting with significant brain edema. A 51-year-old woman was admitted with a 5-day history of headache and nausea, followed by consciousness disturbance. Computed tomography showed cerebellar swelling with obstructive hydrocephalus. Magnetic resonance imaging revealed extensive vasogenic edema in the cerebellum bilaterally. Angiography demonstrated 2 different arteriovenous shunts (AVSs) at peripheral branches of the right anterior inferior cerebellar artery. One was located on the suboccipital surface. It drained through a dilated inferior vermian vein and emptied retrogradely into the contralateral cerebellar veins with marked stagnation. Focal stenosis of the dilated draining vein was present. The other AVS was located on the petrosal surface, which had a slow flow with no angiographic evidence of venous congestion. Given that the latter was believed to be asymptomatic, the former AVS was excised, and histological examination revealed that the lesion consisted of a direct communication of multiple arterial feeding vessels with a single vein, consistent with a diagnosis of pial single-channel arteriovenous fistula. The restriction of venous drainage presumably caused venous hypertension, leading to the brain edema and neurological symptoms.

Adjacent epidermoid cyst and primary central nervous system lymphoma: case report

BACKGROUND

Except for cases with radiotherapy or phacomatosis, multiple primary brain tumors of different histologic types are rare. The authors report the association of an epidermoid cyst and a primary CNS lymphoma.

CASE DESCRIPTION

A 66-year-old man with a 20-year history of gait disturbance was admitted because of recently worsening symptoms. Magnetic resonance imaging showed an abnormal mass in the posterior fossa. The mass lesion had the appearance of a cystic tumor with a large mural nodule. Gross total removal of the tumor was performed. Histologic examination disclosed the cystic portion to be an epidermoid, whereas the nodular portion exhibited the histologic and immunohistochemical features of a malignant lymphoma. The lymphoma cells were shown to harbor EBV by in situ hybridization.

CONCLUSIONS

To our knowledge, this is the first report of the coexistence of an epidermoid cyst and primary CNS lymphoma. When the lesions are adjacent, a definite preoperative diagnosis can be difficult. Epstein-Barr virus-associated CNS lymphoma is rare among the immunologically normal population. The possible pathogenesis for the coexistence of these 2 tumors is discussed.

Stratification of medulloblastoma on the basis of histopathological grading

Medulloblastoma (WHO grade IV) is an embryonal tumour of the cerebellum and the most common malignant central nervous system tumour in children. Despite significant advances in treatment, 5-year survival rates are still less than 70%, suggesting the presence of subgroups with different response to radio/chemotherapy. In the present study, we re-evaluated a series of 347 medulloblastomas from the SIOP II clinical trial of the International Society of Paediatric Oncology to identify features predictive of clinical outcome. Relapse free survival for medulloblastomas with severe anaplasia [5-year rate: S(60)=49.5%], was significantly shorter than for tumours with moderate or mild anaplasia S(60)=65.4%; P=0.001). The difference between both groups was even larger when the presence or absence of extensive apoptosis was included (46.5 vs. 66.7%; P=0.0216). Other histological features including nodularity, necrosis, vascular proliferation and the presence of beta-catenin mutations (7% of cases) were not predictive for relapse free survival. These findings indicate that degree of anaplasia is the most significant histologic feature predictive of the survival of medulloblastoma patients.

Capillary hemangioma of the central nervous system: a comparative study with lobular capillary hemangioma of the skin

Capillary hemangiomas have rarely been reported to develop in the brain or spinal cord. Here we report the histological and immunohistochemical features of ten cases of central nervous system capillary hemangiomas (CNSCH) and compare these to those of lobular capillary hemangioma (LCH) of the skin. CNSCH showed a lobular architecture with lobules that were separated by fibrous tissue septa in six cases. The lobules were composed of numerous, tightly packed, capillary-sized vessels. A highly cellular area was seen in six cases. A blood-filled cavernous space and fibroendothelial papillae that mimicked papillary endothelial hyperplasia were seen in four cases. Stromal edema was observed in nine cases. These features were not statistically different from those of LCH of the skin, although the highly cellular area was more prominent and more frequent in cases of CNSCH. Immunohistochemical studies demonstrated no positive staining of endothelial cells within either lesion for erythrocyte-type glucose transporter protein, which is a selective marker for capillary hemangioma of infancy. Vascular endothelial growth factor immunostaining demonstrated positive cells in the solid or immature-appearing areas without vessel lumen formation in both lesions. Some of the endothelial cells and stromal cells were positive for glucocorticoid receptor immunostaining. The MIB-1 index of CNSCH was variable (mean 5.6%) and the apoptotic index of CNSCH was significantly lower than that of LCH of the skin. CNSCH are benign lesions with histological and immunohistochemical features similar to those of LCH of the skin.