STMO-4 INITIAL EXPERIENCE WITH BRAIN TUMOR SURGERY USING STEALTH AUTOGUIDE

Tissue sampling of brain tumors is generally performed by biopsy with large or small craniotomy and stereotaxic brain biopsy. Recently, Stealth Autoguide, a robotic system for stereotactic deep electrode implantation and brain tumor biopsy in epilepsy, has become available. We report the initial experience of brain tumor surgery using stealth Autoguide in our hospital.Case: A man in his 70s. Left paralysis occurred during chemotherapy for esophageal cancer. Magnetic resonance imaging (MRI) revealed a ring-enhanced lesion from the right basal ganglia to the coronal radiatum. Because he was under steroid administration, he was diagnosed with metastatic brain tumor, malignant lymphoma, malignant glioma, or demyelinating disease. Since paralysis was progressing and MRS was suspected to be a malignant tumor, a stereotactic biopsy using a stealth autoguide was performed. Biopsies were performed with skin incisions of 1 cm or less from two locations that were automatically positioned based on the preoperative planning, and a sufficient amount of tissue was collected from the lesions. No complications such as bleeding were observed. Since the histological diagnosis was glioblastoma, chemotherapy with temozolomide and radiotherapy were promptly started.Brain tumor biopsy using stealth Autoguide allows accurate tissue sampling in a short period of time, and is a very useful tool for brain tumor diagnosis in the future.

One step fabrication of aligned carbon nanotubes using gas rectifier

We report the one-step fabrication of aligned and high-quality carbon nanotubes (CNTs) using floating-catalyst chemical vapor deposition (FCCVD) with controlled fluidic properties assisted by a gas rectifier. The gas rectifier consists of one-dimensional straight channels for regulating the Reynolds number of the reaction gas. Our computational fluid dynamics simulation reveals that the narrow channels of the gas rectifier provide steady and accelerated laminar flow of the reaction gas. In addition, strong shear stress is induced near the side wall of the channels, resulting in the spontaneous formation of macroscopic CNT bundles aligned along the direction of the gas flow. After a wet-process using chlorosulfonic acid, the inter-tube voids inherently observed in as-grown CNT bundles are reduced from 16 to 0.3%. The resulting CNT fiber exhibits a tensile strength of 2.1 ± 0.1 N tex⁻¹ with a Young’s modulus of 39 ± 4 N tex⁻¹ and an elongation of 6.3 ± 0.6%. FCCVD coupled with the strong shear stress of the reaction gas is an important pre-processing route for the fabrication of high-performance CNT fibers.

STMO-12 Efforts for safe malignant brain tumor surgery at our hospital

Although maximal safe resection is the current standard for glioblastoma surgery, its safety and removal rate conflict with each other. Electrophysiological monitoring, such as motor evoked potential monitoring and awake craniotomy, can be utilized as safety measures; not all facilities can perform them. Herein, we present a representative case report on our efforts for a safe malignant brain tumor surgery.

Case: A 77-year-old woman with glioblastoma in the premotor cortex presented with seizure of the upper left lower limb. Her pyramidal tract ran from the medial bottom to the posterior of the tumor. We performed excision from the site using the lowest gamma entropy. We then removed all parts of the tumor, with the exception of the pyramidal tract infiltration, and no paralysis was observed. She was definitively diagnosed with glioblastoma and is currently on maintenance chemotherapy.

As a preoperative examination, we performed cerebrovascular angiography. We then performed various other tests to ascertain the patient’s condition. Considering lesions that affect language, Wada tests were performed regardless of laterality. For all patients with epilepsy onset, preoperative 256-channel electroencephalogram measurement and intraoperative the gamma entropy analysis were performed to confirm epileptogenicity. Considering lesions that affect eloquence, subdural electrodes were placed and brain function mapping was performed the next day. Based on the results, the safest cortical incision site and excision range were determined, and excision was performed on the following day.

Of the 14 operated glioblastoma cases after November 2018, more than 85% of the contrast-enhanced lesions were completely removed in 7 cases, partially removed in 5 cases, and underwent biopsy in 2 cases. Postoperative Karnofsky performance status scores remained unchanged in 11 cases, improved in 1 case, and deteriorated in 2 cases.

Our efforts have resulted in safe and sufficient removal of malignant brain tumors during surgery.

Intracranial mast cells contribute to the control of social behavior in male mice

Mast cells (MCs) exist intracranially and have been reported to affect higher brain functions in rodents. However, the role of MCs in the regulation of emotionality and social behavior is unclear. In the present study, using male mice, we examined the relationship between MCs and social behavior and investigated the underlying mechanisms. Wild-type male mice intraventricularly injected with a degranulator of MCs exhibited a marked increase in a three-chamber sociability test. In addition, removal of MCs in Mast cell-specific Toxin Receptor-mediated Conditional cell Knock out (Mas-TRECK) male mice showed reduced social preference levels in a three-chamber sociability test without other behavioral changes, such as anxiety-like and depression-like behavior. Mas-TRECK male mice also had reduced serotonin content and serotonin receptor expression and increased oxytocin receptor expression in the brain. These results suggested that MCs may contribute to the regulation of social behavior in male mice. This effect may be partially mediated by serotonin derived from MCs in the brain.

HGG-29. A CASE OF CIRCUMSCRIBED HIGH-GRADE ASTROCYTOMA WITH ATRX AND CDKN2A/B ALTERNATIONS WHO WAS INITIALLY DIAGNOSED AS GLIOBLASTOMA AND HAS 20 YEARS SURVIVAL

Pediatric high-grade gliomas are rare and often hard to classify, which grow locally and show longer survival than diffuse high-grade gliomas in adults. We report a case of circumscribed high-grade astrocytoma who was initially diagnosed as glioblastoma and has 20 years survival. A 7-year-old girl suffered from epileptic seizure due to a left occipital lobe tumor. The tumor was resected in another hospital and diagnosed as glioblastoma. The tumor disappeared after extended local irradiation and chemotherapy using nimustine hydrochloride (ACNU) and cisplatin (CDDP). Eighteen years after initial onset, first recurrence was confirmed as the intra-tumoral hemorrhage. The tumor was resected and diagnosed as anaplastic oligoastrocytoma. After 6 courses of temozolomide (TMZ), the tumor disappeared. Twenty years after initial onset, the second local recurrence was confirmed. Although gamma knife and TMZ was performed, the tumor did not disappear. The tumor was surgically resected. Histopathology showed localized growth with some infiltration and mitosis but lacked pseudopallisading and microvascular proliferation. The tumor was diagnosed as circumscribed high-grade astrocytoma. Immunostaining revealed ATRX nuclear loss and CDKN2A / B homozygous deletion. After 10 courses of TMZ, the third local recurrence was confirmed. The tumor was completely removed and has not occurred recurrence more than 3 months after the last operation. Circumscribed high-grade glioma is expected to survive longer than invasive glioma. Pediatric gliomas should differ from adult gliomas in the genes of tumorigenesis. Care should be taken for its diagnosis and treatments. We also need a new classification based on histology and gene profile. HGG-30, ANALYSIS OF PEDIATRIC GLIOMAS IN OUR INSTITUTE Kaoru Tamura, Mai Fujioka, Masae Kuroha, Motoki Inaji, Yoji Tanaka, Tadashi Nariai, and Taketoshi Maehara; Tokyo Medical and Dental University, Tokyo, Japan. PURPOSE: Recent advances in genetic interrogation of pediatric glioma increase the importance of molecular diagnosis using surgical specimen. However, surgical resection may be avoided to preserve quality of life, especially in brain stem glioma cases. We retrospectively examined diagnosis and treatment of pediatric gliomas in our hospital. METHODS: This study includes 14 consecutive glioma patients under the age of 18 who underwent initial treatment at our hospital from 2000 to 2019. Histopathological diagnosis, clinical course and molecular status such as IDH, H3F3A and BRAF were analyzed. RESULTS: 5 patients (1 pilocytic astrocytoma (PA), 3 diffuse astrocytomas, 1 oligodendroglioma were treated only by surgical resection (group A). 7 patients (1 PA, 1 anaplastic oligodendroglioma, 2 diffuse midline gliomas and 3 glioblastomas (GBM)) received radiation and/or chemotherapy after surgical resection (group B). 2 diffuse intrinsic pontine gliomas (DIPG) received radiation and chemotherapy without surgical resection (Group C). No IDH mutation was observed in all pathological specimen obtained cases. BRAF alteration was observed in all PA cases. 1 case of GBM had BRAF V600Emutation and the other had H3K27M mutation. During a median of 7.7 years of follow-up, group A patients have no recurrence. Group B includes various diagnosis and prognosis. 2 group C patients diagnosed DIPG by MRI showed different clinical courses. CONCLUSION: Pediatric gliomas include diverse biological subgroups and show broad range of clinical behavior. Since pediatric glioma has a low incidence and a wide variety of genetic mutations, multicenter study is important to improve the treatment of pediatric glioma.

Surgical clip occlusion of the V3 segment to prevent recurrent cerebral infarction associated with extracranial vertebral artery dissection: A case report

Background:

Recurrent cerebral infarction caused by traumatic extracranial vertebral artery dissection (EVAD) is treated medically and surgically. We report a case of EVAD that was treated using surgical clip occlusion of the V3 segment to prevent recurrent cerebral infarction.

Case Description:

A 48-year-old man was admitted for a cerebral infarction caused by EVAD and was treated using 200 mg/day cilostazol. Afterward, the cerebral infarction recurred. Digital subtraction angiography revealed that initial severe stenosis of the VA ostium resulted in the final occlusion and that collateral vessels to the VA remained. We continued antiplatelet therapy, but the cerebral infarction recurred due to thromboembolism of the collateral vessels. Parent artery occlusion was planned. We exposed the V3 segment of the VA and clipped it to prevent the recurrence of cerebral infarction.

Conclusion:

Surgical clip occlusion of the V3 segment was effective for treating recurrent cerebral infarction caused by traumatic EVAD that had remained an issue despite continuing medical therapy.

COT-18 TWO CASES OF GLIOBLASTOMA WITH ASYMPTOMATIC PULMONARY ARTERY EMBOLISM AND DEEP VEIN THROMBOSIS FROM ADMISSION TO HOSPITAL

Patients with malignant tumors are susceptible to concurrent venous thromboembolism. We report two cases of glioblastomas that showed asymptomatic pulmonary embolism and deep vein thrombosis on admission. The first case was a 77-year-old male. He was referred to our clinic for a tumor found in the left temporal lobe on computed tomography scan performed when he suffered pneumonia. On admission,he had a Karnofsky performance status (KPS) score of 50 and an elevated D-dimer level (16.46 μg/ml). Pulmonary embolism and deep vein thrombosis were noted on detailed examination. Direct oral anticoagulant (DOAC) therapy resulted in the disappearance of pulmonary embolism. On biopsy,the tumor was diagnosed as glioblastoma. The patient underwent radiation therapy in combination with chemotherapy. The second case was a 71-year-old female. She developed a disorder of consciousness and was admitted to a clinic. Brain magnetic resonance imaging (MRI) revealed a high T2 signal area in the left temporal lobe. The patient was initially diagnosed with encephalitis. Though the consciousness disorder improved quickly,she was referred to our clinic after a hyperintense area was observed on MRI. On admission,she had a KPS score of 100,and an elevated D-dimer level (7.59μg/ml),revealing pulmonary embolism and deep vein thrombosis. She was started on a DOAC and underwent surgical removal of the tumor via craniotomy. She was diagnosed with glioblastoma and underwent radiation therapy in combination with chemotherapy. Approximately 20% of the patients with glioblastomas suffer concurrent symptomatic venous thromboembolism. The incidence of venous thromboembolism is further elevated in patients with a poor KPS score or elderly people. Many patients with glioblastomas suffer asymptomatic venous thromboembolism. In this report,asymptomatic venous thromboembolism was noted in patients with a good KPS score. In glioblastoma patients,it is necessary to test for venous thromboembolism by measuring D-dimer levels before surgery.

Enhancement of fear learning in PPARα knockout mice

Peroxisome proliferator-activated receptor alpha (PPARα) is a member of the nuclear receptor superfamily and regulates fatty acid oxidation. Although PPARα is expressed not only in the peripheral tissues but also in the brain, its role in higher brain function is unclear. In this study, we investigated the role of PPARα in the control of behavior, including memory/learning and mood change, using PPARα knockout (KO) mice. A significant difference between wild-type (WT) and KO mice was seen in the passive avoidance test, demonstrating that KO mice showed enhanced fear leaning. In the amygdala of KO mice, the levels of dopamine and its metabolites were increased, and the mRNA expression of dopamine degrading enzyme was decreased. When dopamine D1 receptor antagonist was administered, the enhanced fear learning observed in KO mice was attenuated. These results suggest that PPARα is involved in the regulation of emotional memory via the dopamine pathway in the amygdala.

Supine No-Retractor Method in Microvascular Decompression for Hemifacial Spasm: Results of 100 Consecutive Operations

Objectives In microvascular decompression (MVD) for hemifacial spasm (HFS), the patient is placed in the lateral or park-bench position that is complicated and uncomfortable for anesthesiologists, nurses, and even the patient. Careless retraction of the cerebellum by a spatula could be the major cause of surgical complications. In our method, a patient is laid supine avoiding the complicated positioning. The subfloccular approach from a small cranial window sited on the more lateral and basal side of the occipital cranium enables the surgeon to reach all the segments of the facial nerve root without a spatula. We introduce our surgical procedures in detail along with our excellent results. Methods A total of 100 consecutive patients experiencing primary HFS were operated on with MVD by a single surgeon in our institution from August 2012 to April 2014. Results Overall, 94 patients showed the complete disappearance or a satisfactory alleviation of HFS. De novo neurologic deficits were not encountered after surgery including hearing impairment. In 47 cases, multiple offending vessels were observed in multiple possible affected sites in addition to the root entry/exit zone. Conclusions We believe this approach is superior for the safe and precise decompression of any part of the facial nerve root.

Clinical characteristics and treatment outcomes of nineteen Japanese patients with gastrointestinal bezoars

OBJECTIVE

To analyze the clinical characteristics of patients with gastrointestinal bezoars and their response to therapy. Patients We retrospectively reviewed the cases of 19 patients diagnosed with gastrointestinal bezoars at the Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences or one of 15 collaborating institutions between December 2004 and August 2013. We investigated the epidemiology and etiology of the gastrointestinal bezoars by determining the gender, age at diagnosis, medical history, symptoms, complications, modalities used for diagnosis, treatments, outcomes and bezoar location, color and contents.

RESULTS

There were 17 patients with gastric bezoars and two patients with small intestinal bezoars. All patients were 62 years of age or older, except for one case of a trichobezoar in a 10-year-old patient. Some of the patients had a history of surgery of any part of the gastrointestinal tract (n=5) and/or diabetes mellitus (n=2). The two patients with small intestinal bezoars required surgical removal in order to relieve ileus. Approximately one-half of the patients with gastric bezoars had ulcerations in the stomach (9/17 patients, 52.9%) and/or gastrointestinal bleeding (8/17, 47.1%). Endoscopic fragmentation was performed in 10 patients, whereas bezoar dissolution was achieved with a gastroprokinetic agent (n=1) and without any treatment (n=3) in the remaining cases.

CONCLUSION

As previously reported, elderly individuals with a positive history of surgery and/or diabetes mellitus were observed in this bezoar patient series. Gastric ulcers and gastrointestinal bleeding were frequently observed. The majority of patients underwent endoscopic fragmentation, while spontaneous resolution of the gastric bezoar was observed in several cases.

Helix-Sense-Selective Polymerization of Achiral Phenylacetylenes with Two N-Alkylamide Groups to Generate the One-Handed Helical Polymers Stabilized by Intramolecular Hydrogen Bonds

In this study, we investigated the helix-sense-selective polymerizations of newly synthesized achiral phenylacetylenes having two N-alkylamide groups, such as 3,5-bis(dodecylamide)phenylacetylene (DAPA), 3,5-bis(octylamide)phenylacetylene (OAPA), and 3,5-bis(butylamide)phenylacetylene (BAPA), by using a chiral rhodium catalyst system ([Rh(nbd)Cl]₂-(R)-(+)-1-phenylethylamine [(R)-PEA]). Poly(BAPA) was insoluble in any solvents. On the other hand, poly(DAPA) and poly(OAPA) were soluble in toluene, THF, and CHCl₃, and the obtained polymers showed intense circular dichroism signals at the absorption region of the main chain in the UV-vis region. This result suggested those polymers were present in helical conformations with an excess of one-handed screw sense. The chiral helix structures of the formed polymers were stable in toluene at room temperature for a long time because of intramolecular hydrogen bonds. This result is the second example about polyacetylenes with one-handed helical conformation stabilized by intramolecular hydrogen bonds.

Proton pump inhibitor dose-related healing rate of artificial ulcers after endoscopic submucosal dissection: a prospective randomized controlled trial

BACKGROUND/AIMS

Two studies have reported on the superiority of a proton pump inhibitor (PPI) compared with a histamine-2-receptor antagonist for the treatment of artificial ulcers after endoscopic submucosal dissection (ESD), but the optimal dose of PPI remains to be defined. The aim of this study was to evaluate the possibility of reducing the dose of PPI. The authors thus compared 30 mg (standard-dose) and 15 mg (half-dose) lansoprazole in terms of ulcer healing, prevention of bleeding and quality of life.

METHODS

91 patients with gastric mucosal neoplasm were enrolled. All patients who underwent ESD were administered lansoprazole 30 mg daily during the first week, after which they were randomly assigned to either the standard-dose or half-dose group.

RESULTS

One patient in each group developed hematemesis. The stage of ulcers, ulcer reduction ratios and scores on the Gastrointestinal Symptom Rating Scale did not differ at 28 and 56 days. The costs of PPI for the half-dose group and standard-dose group were 7,326.5 and 11,698.4 JPY, respectively, i.e. a difference of 471.9 JPY.

CONCLUSIONS

A reduced dose of PPI after 1 week of ESD was equivalent in treatment performance to the standard dose and cheaper.

Factors associated with adherence to combination therapy of interferon and ribavirin for patients with chronic hepatitis C: importance of patient's motivation and physician's treatment experience

BACKGROUND/AIMS

Adherence to combination therapy with interferon (IFN) or pegylated IFN plus ribavirin for chronic hepatitis C patients is important for a better virological response. However, the impact of the patient's treatment experience and treatment centre on adherence to combination therapy has not been fully analysed. In this prospective study, we analysed the factors that might have an effect on adherence to therapy in patients who had initial or retreatment IFN therapy.

PATIENTS AND METHODS

We consecutively enrolled 363 patients with chronic hepatitis C; 221 were IFN naïve and 142 were undergoing retreatment. The mean ages of the naïve and retreatment groups were 54.8 and 55.7 years respectively. IFN alpha-2b was administered daily for 2 weeks, followed by three times per week for 22 weeks, while ribavirin was administered daily. We evaluated the tolerability and response to combination therapy and analysed its relevant factors.

RESULTS

Of the 363 patients, 189 (52%) achieved 80% adherence. The multivariate logistic regression analysis revealed that retreatment, centre with more patients treated, patient age (<55 years), male, genotype 2 and dosage of IFN per weight (<0.13 million units/kg) were associated with achievement of 80% adherence to combination therapy. Accordingly, the achievement of 80% adherence was more frequent in the retreatment (62%) than that in the naïve group (46%) (P<0.01) and in centres with more patients treated (57%) than in those with less patients treated (46%) (P=0.03).

CONCLUSION

The present data suggest that the patient's motivation and the physician's treatment experience may be important for a better adherence to combination therapy for patients with chronic hepatitis C.

Novel chromoendoscopic method using an acetic acid-indigocarmine mixture for diagnostic accuracy in delineating the margin of early gastric cancers

BACKGROUND AND AIM

Recent endoscopic imaging techniques for recognition of unclear lesions in the stomach (e.g. narrow band imaging, magnifying endoscopy) require special equipment and therefore are not commonly used. The aim of the present study was to estimate the accuracy of a new chromoendoscopic method using an acetic acid-indigo carmine mixture (AIM) in diagnosing early gastric cancers (EGC).

METHODS

Studied were 108 EGC lesions in 104 patients. EGC were initially observed by white light (WL) after which indigo carmine (IC) solution was sprinkled onto the gastric mucosa. Images by WL and IC observation were recorded by a digital filing system. After washing away IC solution with water, AIM solution was sprinkled onto the gastric mucosa and images were recorded. Margin lines of EGC determined by each observation were drawn on recorded images by graphic software for comparison with resected specimens. After lines were similarly drawn on images of resected specimens, the extent of the lesions was compared with that determined by endoscopic images.

RESULTS

Diagnostic accuracy of WL, IC, and AIM observations were 50.0%, 75.9% and 90.7%, respectively. No adverse events occurred with the AIM method.

CONCLUSIONS

This chromoendoscopic method can be used to delineate the margin of EGC accurately, easily, safely and inexpensively.

Risk factors associated with local recurrence of early gastric cancers after endoscopic submucosal dissection

BACKGROUND

Although endoscopic submucosal dissection (ESD) is expected to reduce the local recurrence of gastric cancers, we still experience cases of recurrence after an ESD.

OBJECTIVE

To characterize clinical and pathologic features of cases with local recurrence of early gastric cancer after an ESD.

DESIGN

A prospective cohort study.

SETTING AND PATIENTS

A total of 306 patients with gastric cancers removed by ESD at Okayama University Hospital and Tsuyama Central Hospital between March 2001 and December 2005 were enrolled.

INTERVENTION

ESD.

MAIN OUTCOME MEASUREMENT

Local recurrence.

RESULTS

The incidence of a complete en bloc resection was 80.4% when pathologically evaluated. Within a median follow-up period of 26 months (12-64 months), a local recurrence was found in 7 cases, all of which had been declared incomplete resections. One patient underwent a second ESD, and the remaining 6 underwent a surgical resection. All removed lesions were mucosal cancers. No lymph-node metastases were found in patients with a surgical resection. There was a significant correlation between the incidence of an incomplete resection and that of a local recurrence (P < .0001). Among the clinical characteristics, tumor size (>30 mm vs <20 mm; odds ratio [OR] 16 mm [95% CI, 2.0-130 mm]) and tumor location (upper vs middle or lower; OR 7.6 [95% CI, 1.3-45]) were identified as factors that were significantly associated with the incidence of a local recurrence.

LIMITATION

Short follow-up duration.

CONCLUSIONS

The incidence of a local recurrence was strongly associated with that of an incomplete resection. The frequency of a local recurrence also showed significant correlations with the tumor size and location within the stomach.

Rathke's cleft cysts: differentiation from other cystic lesions in the pituitary fossa by use of single-shot fast spin-echo diffusion-weighted MR imaging

OBJECTIVE

Rathke's cleft cysts are often difficult to differentiate from other sellar cystic lesions using conventional MR imaging. The purpose of this study was to investigate the usefulness of single-shot fast spin-echo (SSFSE) diffusion-weighted MR imaging (DWI) in the diagnosis of a Rathke's cleft cyst.

PATIENTS AND METHODS

We examined retrospectively 29 patients with a histologically verified sellar or suprasellar lesion containing a fluid component; 12 patients had a Rathke's cleft cyst, 6 patients a craniopharyngioma, 5 patients a haemorrhagic pituitary adenoma, and 6 patients a cystic pituitary adenoma). Several regions of interest (ROIs) for apparent diffusion coefficient (ADC) measurements were identified in the fluid components of the lesions. For comparison, ADC values were normalized using a relative ADC (rADC), which was determined by dividing the ADC values of lesions by those of normal white matter and expressing the quotient as a ratio.

RESULTS

SSFSE provides diffusion-weighted images without significant susceptibility artifacts. DWI-SSFSE revealed Rathke's cleft cysts as hypointense relative to the normal brain parenchyma in all cases. The mean value of ADC for Rathke's cleft cysts was 2.12 x 10(-3) mm(2)/sec. Both the ADC and relative ADC of the Rathke's cleft cysts were significantly increased compared to those of the cystic components of craniopharyngiomas and haemorrhagic components of pituitary adenomas in the subacute phase (P < 0.05). There was not a statistically significant difference between Rathke's cleft cysts and cystic components of pituitary adenomas (P < 0.05).

CONCLUSIONS

DWI-SSFSE with ADC values provides objective information in the differential diagnosis of Rathke's cleft cysts from other sellar cystic lesions. In addition, DWI-SSFSE with ADC values is useful for differentiating Rathke's cleft cysts from craniopharyngiomas and haemorrhagic pituitary adenomas.

Electromagnetic field system for transsphenoidal surgery on recurrent pituitary lesions - technical note

BACKGROUND

Post operative scar tissue makes transsphenoidal surgery for recurrent pituitary lesions very difficult. However, with the use of a new cautery system, known as the EMF system, we were able to perform the surgical procedures with relative ease. In this article, we report the advantages and clinical applications of this new instrument in transnasal reoperation.

METHODS

The EMF system generates a high frequency current of 13.56 MHz that is focused on the target. This enables it to coagulate, cut, and vaporize tissue in a pinpoint fashion. The bayonet and pencil-type hand pieces of the EMF system are slim, and the tips of the probe are flexible. This enables the surgeon to easily reach deep narrow spaces. We have used the EMF system for transsphenoidal surgery on recurrent pituitary lesions in 18 patients. The system was used to cut and vaporize scar tissue and vaporize firm and fibrotic tumor tissue.

RESULTS

During surgery, the system could easily cut and vaporize scarred tissues in the nasal cavity, the sphenoid sinus, and the sella, without damage to the surrounding tissue. In addition, in 3 patients who had extremely fibrotic and firm tumors, we were able to easily vaporize the tumor with safety.

CONCLUSIONS

The EMF system enables the surgeon to cut and vaporize tissue with ease and with minimal injury to the surrounding structures. It was particularly valuable in the resection of firm tumors. It may also shorten the operating time because of quick vaporization of the firm tissue.

[A case of cerebellar tuberculoma]

We report a case of cerebellar tuberculoma presenting with headache, without any specific data. A 22-year-old male had headache for recent three months. Because of detection of the tubercle bacillus in his sputum, he was suspected the pulmonary tuberculosis and the tuberculous meningitis. On admission the cerebrospinal fluid revealed no abnormal data and the tubercle bacillus was not detected in the culture. We started medication for the tuberculosis. MRI demonstrated a mass lesion at the right cerebellum, suggesting the presence of a tuberculoma. He underwent total removal of the tumor via the supracerebellar route. Histological examination revealed tuberculoma when there are no abnormal data. The intracranial tuberculoma may be confused with an intracranial neoplasm. It is important to make an overall evaluation to diagnose tuberculosis; for instance, compromised high age, HIV, and the type of steroid administered, will increase intracranial tuberculoma. In this report, we describe a cerebellar tuberculoma without any abnormal data, suggesting that intracranial tuberculoma should be considered in the differential diagnosis of any intracranial mass lesion.

[A case of a hemorrhagic non-functioning pituitary adenoma presenting with abducens nerve palsy]

A pituitary adenoma presenting with isolated abducens nerve palsy is an extremely rare occurrence. The authors report a rare case of a hemorrhagic non-functioning pituitary adenoma presenting with isolated abducens nerve palsy. The etiology of isolated abducens nerve palsy by a pituitary tumor is discussed. A 34-year-old male presented with severe headache, vomiting, right-sided ophthalmic pain, and diplopia. On admission, he had right-sided isolated abducens nerve palsy. Magnetic resonance (MR) images demonstrated a less-enhancing intra-and suprasellar mass lesion with intratumoral hemorrhage and right-sided slight cavernous sinus invasion, that exhibited an iso-high mixed intensity on T1-weighted image and a low-high mixed intensity on T2. Cerebral angiogram revealed no abnormality. The pituitary hormone function was within normal range. The tumor was totally resected via the transnasal route. The histological diagnosis was a typical non-functioning pituitary adenoma with hemorrhage. The abducens nerve palsy was completely resolved 7 months after surgery. It was supposed that the isolated abducens nerve palsy was caused by the direct compression of abducens nerve in the cavernous sinus by the extension of a pituitary tumor and hematoma. Pituitary adenoma should be considered in the differential diagnosis of abducens nerve palsy. Early diagnosis and transsphenoidal surgery is recommended to improve the abducens nerve palsy.

Clinicopathological examination of glioma by proton magnetic resonance spectroscopy background

Automation of proton magnetic resonance spectroscopy (MRS) in recent years has made it possible for MRS measurement to be performed in a shorter time than before, and the number of reports of its usefulness for the assessment of glioma malignancy has been increasing in the past several years. We studied the efficacy of proton MRS when used for glioma and conducted clinicopathological examination of glioma. The subjects were 15 patients who had received a pathological diagnosis of glioma at our hospital (6 cases of glioblastoma, 1 case of anaplastic astrocytoma, 4 cases of low-grade astrocytoma, and 4 cases of radiation necrosis); Siemens Magnetom Vision 1.5T was used for the study. Regions of interest (ROIs) were defined as the areas where abnormal signals were found on magnetic resonance imaging (MRI). Areas of primary peaks, such as choline (Cho), N-acetylaspartate (NAA), and lactate (Lac), were measured, and the ratios to normal brain tissue were examined. This study revealed a tendency of increased malignancy of glioma with a decrease in NAA. Some cases also displayed a decrease in Cho with an increase in malignancy. Assessment of malignancy must not be based on a single ROI alone, but several ROIs should be assessed comprehensively. Measurement was difficult when the tumor volume was small. Because diagnosis of very early glioma by MRS seemed difficult, other adjunctive diagnoses may be necessary. Proton MRS is very useful for diagnosis of glioblastoma.

Gliomatosis cerebri in a young patient showing various cranial nerve manifestations: a case report

A case of gliomatosis cerebri in a 27-year-old man showing various cranial nerve manifestations is described. He was diagnosed as having cranial mononeuritis multiplex (bilateral oculomotor nerve paralysis, left facial nerve paralysis, bulbar palsy manifestations, and hypoglossal nerve paralysis) and was hospitalized in the neurology department on August 1, 2000. Although he continued to visit the neurology department after discharge, his manifestations showed no improvement. He was sent to our department for brain biopsy in August 2001. A biopsy performed at the Sylvian fissure from the frontal lobe/temporal lobe cortex showed high intensity on T2-weighted and Flair magnetic resonance imaging (MRI). The pathological findings were diffuse low-grade astrocytoma infiltrating between the pia mater and the cerebral cortex. We believed that the astrocytoma spreading on the subpia mater was responsible for the various cranial nerve manifestations, and we started whole-brain irradiation (46 Gy) + interferon (IFN)-beta D.I.V. from September 2001. The pathological findings of the brain biopsy showed diffuse astrocytoma. The clinical presentation was dramatically improved after radiotherapy. It seemed that this tumor had spread along the subpia mater and subependyma. When he was discharged in early December, he walked by himself. The characteristic features of this case are that no lesion in the cerebellum or brain stem was found on MRI, even though the main manifestations were cerebello-brain stem manifestations, and biopsy of the cerebral cortex revealed astrocytoma. It should be noted that the clinical manifestations of astrocytoma in some cases are dissociated from the imaging observations.

Transcortical transchoroidal fissure approach for ruptured distal posterior cerebral artery (P2-P3 junction) aneurysm associated with packed intraventricular hemorrhage--two case reports

A 56-year-old man with ruptured right P2-P3 junction aneurysm and a 66-year-old man with ruptured left P2-P3 junction aneurysm of the posterior cerebral artery associated with acute-stage packed intraventricular hemorrhage. The aneurysms were successfully clipped through the transcortical transchoroidal fissure approach. This approach requires less retraction of the temporal lobe, provides a wider surgical field, and the P2 segment can be easily reached. The present approach is very useful for the treatment of ruptured aneurysms at the P2-P3 junction, in particular for acute stage surgery associated with packed intraventricular hemorrhage.

[Treatment for the ruptured bilateral vertebral dissecting aneurysms]

We report a case of a bilateral vertebral dissecting aneurysm associated with subarachnoid hemorrhage. Proximal ligation of the vertebral artery on the ruptured side combined with wrapping of the contralateral dissection failed to prevent fatal rebleeding. Since enlargement of the contralateral dissection was observed by postoperative angiography, rupture of the growing contralateral dissecting aneurysm may have caused rebleeding. Hemodynamic changes following the occlusion of one vertebral artery might have led to enlargement and subsequent rupture of the contralateral dissection. Direct wrapping was unable to prevent enlargement of the dissection, so radical surgery including bilateral vertebral artery occlusion combined with vascular reconstruction may be the treatment of choice for this type of lesion.

Usefulness of gallium-67 scintigraphy in neurohypophyseal germinoma

The application of gallium-67 (67Ga) citrate has not been reported for the detection of an intracranial germinoma. The purpose of this report is to further evaluate the effectiveness of 67Ga scintigraphy in neurohypophyseal germinomas. 67Ga studies in five male patients with histologically verified intracranial pure germinomas were evaluated. Two germinomas were located in the neurohypophysis, two in the pineal region, and one in both the neurohypophysis and pineal region. The control group included 36 patients with histologically verified pituitary macro-adenomas. 67Ga study at the time of original diagnosis showed an abnormal accumulation in two neurohypophyseal germinomas, and negative accumulation in the other germinomas. In the two patients with neurohypophyseal germinomas, 67Ga study showed an abnormal accumulation in the intracranial tumour region in accordance with magnetic resonance (MR) findings. After postoperative irradiation or chemoradiotherapy, MR imaging and 67Ga studies revealed the complete disappearance of this tumour and no metastatic spread. In one of these two patients, a whole-body 67Ga study demonstrated multiple bone metastases one year later, and the reduction of these metastatic regions after chemotherapy. 67Ga study disclosed negative accumulation in all 36 pituitary macroadenomas. Although 67Ga uptake by neurohypophyseal germinomas may not be specific for this condition, this approach may provide some clues for diagnosing patients with neurohypophyseal germinomas.