Metastasis infiltrating tumor to meningioma: a case report.

BACKGROUND: There have been many reports of tumor-to-tumor metastasis, in which cancer metastasizes directly into meningiomas. However, metastasis infiltrating tumors in which cancer metastasizes around meningiomas are rare. Therefore, we report a case of metastasis originating from lung cancer that infiltrated meningioma. CASE PRESENTATION: A 79-year-old Japanese woman underwent head magnetic resonance imaging for brain metastasis screening before lung cancer surgery. At that time, asymptomatic meningioma of the left frontal region was accidentally found. Magnetic resonance imaging 6 months later revealed a lesion suspected to be a metastatic brain tumor close to the meningioma. Brain tumor resection was performed, and histopathological diagnosis was meningioma and metastatic brain tumor. Metastatic cancer had invaded the meningioma at the boundary between the brain tumor and metastasis. CONCLUSIONS: A sudden change in imaging findings on routine examination of meningiomas in patients with lung carcinoma may indicate a metastatic brain tumor. The form of cancer metastasis to meningioma is not limited to tumor-to-tumor metastasis, but also includes metastasis infiltrating tumors near the meningioma.

Local and systemic factors associated with quantitative stiffness of carotid plaque.

PURPOSE: Plaque stiffness in carotid artery stenosis is a clinically important factor involved in the development of stroke and surgical complications. The purpose of this study was to clarify which local and systemic factors are associated with the quantitatively measured stiffness of plaque. METHODS: The subjects were 104 consecutive patients who underwent carotid endarterectomy at our institution. To measure quantitative stiffness of plaque, we used an industrial hard meter in the operating room within 1 h after removal of plaque. Local factors related to carotid plaque hardness were evaluated, including maximum intima-media thickness (max IMT), degree of stenosis using the European Carotid Surgery Trial (ECST), presence of ulceration or calcification, and echo brightness on preoperative carotid ultrasound. The degree of stenosis was also evaluated using the North American Symptomatic Carotid Endarterectomy Trial method in digital subtraction angiography. Age, sex, and presence or absence of hypertension, diabetes, and dyslipidemia (low-density lipoprotein cholesterol and triglyceride [TG] levels) served as systemic factors and were compared with the quantitative stiffness of carotid plaque. RESULTS: In multivariate analysis, ECST stenosis degree, calcification, and IMT max as local factors affected plaque stiffness. As a systemic factor, plaque stiffness was statistically significantly negatively correlated with TG values in multivariate analysis (p < 0.05). CONCLUSION: The quantitative stiffness of the plaque was negatively correlated with TG levels as a systemic factor in addition to local factors. This might suggest that reducing high TG levels is associated with plaque stabilization.

Differentiation between Anterior and Posterior Roots Using Compound Muscle Action Potential in Intradural Extramedullary Spinal Tumor Surgery.

This study aims to determine the cutoff values for the compound muscle action potential (CMAP) stimulus in anatomically identified anterior (motor nerve) and posterior roots (sensory nerve) during cervical intradural extramedullary tumor surgery. The connection between CMAP data from nerve roots and postoperative neurological symptoms in thoracolumbar tumors was compared with data from cervical lesions. The participants of the study included 22 patients with intradural extramedullary spinal tumors (116 nerve roots). The lowest stimulation intensity to the nerve root at which muscle contraction occurs was defined as the minimal activation intensity (MAI) in the CMAP. In cervical tumors, the MAI was measured after differentiating between the anterior and posterior roots based on the anatomical placement of the dentate ligament and nerve roots. The MAIs for 20 anterior roots in eight cervical tumors were between 0.1 and 0.3 mA, whereas those for 19 posterior roots were between 0.4 and 2.0 mA. The cutoff was <0.4 mA for both the anterior and posterior roots, and sensitivity and specificity were both 100%. In thoracolumbar tumors, the nerve root was severed in 12 of 14 cases. All MAIs were determined to be at the dorsal roots as their scores were higher than the cutoff and did not indicate motor deficits. The MAIs of the anatomically identified anterior and posterior root CMAPs were found to have a cutoff value of <0.4 mA in the cervical lesions. Similar MAI cutoffs were also applicable to thoracolumbar lesions. Thus, CMAP may be useful in detecting anterior and posterior roots in spinal tumor surgery.

Academic Activities of Female Neurosurgeons in All Branch Meetings of the Japan Neurosurgical Society.

This study aims to evaluate the academic activities of female neurosurgeons at all branch meetings of the Japan Neurosurgical Society and identify related issues they encountered. The programs of all seven branch meetings of the Japan Neurosurgical Society (Hokkaido, Tohoku, Kanto, Chubu, Kinki, Chugoku/Shikoku, and Kyushu) were used to determine the number of presentations and chairpersons by sex. The covered period was from January 2008 to December 2020, which was available for viewing during the survey. Of note, only the Kinki branch used data from January 2008 to December 2019. The Neurologia Medico-chirurgica (NMC), the journal of the Japan Neurosurgical Society, was also reviewed to identify publication achievements during the same period. In all seven branches, the percentage of presentations given by female physicians increased from 7.9% in 2008 to 9.6% in 2020 (p < 0.05).Conversely, the percentage of female chairpersons in all branch meetings did not change over time and it was significantly lower (1.1%) than that of female presenters (7.9%) for all branch meetings combined in over 13 years (p < 0.01). In the NMC, the number of articles with female physicians as first authors did not increase or decrease over the years. We conclude that efforts to smoothly promote female neurosurgeons as chairpersons and increase the number of female first authors are necessary to facilitate their academic activities.

Diagnosis and treatment of vertebral artery injuries due to blunt trauma: A case series.

Blunt traumatic vertebral artery injuries are rare, but they cause rapid secondary strokes with worsening prognoses. We report four blunt traumatic vertebral artery injury cases that were diagnosed before developing stroke and successfully treated with coil embolization. All four patients were male, aged between 45 and 71 years (mean 57 years). The injuries were caused by road accidents in 2 cases and falls in 2 cases. The GCS at initial examination was 15, except for one case of hypoxic encephalopathy associated with pulmonary contusion (11 points). The vertebral arteries were completely occluded (Denver grade IV). Before treatment, only one patient had a mild right cerebellar hemispheric stroke, but three patients were asymptomatic. All patients underwent coil embolization (2 on 0 days, 1 on 7 days, and 1 on 17 days), and the postoperative course was uneventful. The neuroradiological imaging studies should be performed as early as possible in vertebral artery injuries due to blunt neck trauma. Moreover, endovascular coil embolization is a safe, effective treatment for blunt traumatic vertebral artery injuries.

Intraperitoneal hemorrhage due to segmental arterial mediolysis associated with cerebral vasospasm after subarachnoid hemorrhage.

A man in his 50s with no significant past medical history developed subarachnoid hemorrhage due to ruptured left middle cerebral artery aneurysm. On the ninth hospital day, he had a ruptured visceral aneurysm with segmental arterial mediolysis, and we successfully treated with transarterial embolization using metallic coils.

A Case of Lateral Ventricular Subependymoma with Intratumoral Hemorrhage via Neuroendoscopic Surgery.

Subependymoma (SE) is a rare, usually asymptomatic, brain tumor predominantly affecting older adults and occurring in the fourth and lateral ventricles. We report a rare case of SE with intratumoral hemorrhage that could be removed by neuroendoscopy. The 81-year-old patient had been followed as an outpatient for 10 years due to an intraventricular tumor. It did not grow over the patient's lengthy follow-up. The patient was transferred to our hospital after he fainted near his home; at the time of admission, he had mild consciousness disturbance, and his Glasgow Coma Scale score was 10 points (E3V3M4). Computed tomography showed intratumoral hemorrhage and slight ventricular enlargement. Magnetic resonance (MR) imaging showed a 4 cm-sized tumor in the anterior horn of the right lateral ventricle. The lesion appeared as a mixed-intensity solid tumor and showed irregular enhancement with gadolinium. The patient underwent neuroendoscopic tumor resection on the 30th day of the patient's hospital stay. A histopathological examination revealed small tumor cells with round nuclei scattered in the glial fibrillary background. Immunostaining was positive for glial fibrillary acidic protein; these findings are consistent with an SE diagnosis. The patient in this study had hypertension and used anticoagulants, risk factors for intratumoral hemorrhage. For intraventricular tumors with bleeding-particularly in older or more physically frail patients-minimally invasive neuroendoscopic surgery should be considered an option for tumor resection.

Quantitative comparison between carotid plaque hardness and histopathological findings: an observational study.

BACKGROUND: Plaque hardness in carotid artery stenosis correlates with cerebral infarction. This study aimed to quantitatively compare plaque hardness with histopathological findings and identify the pathological factors involved in plaque hardness. METHODS: This study included 84 patients (89 lesions) undergoing carotid endarterectomy (CEA) at our institution. Plaque hardness was quantitatively measured immediately after excision using a hardness meter. Collagen and calcification were evaluated as the pathological factors. Collagen was stained with Elastica van Gieson stain, converted to a gray-scale image, and displayed in a 256-step histogram. The median gray-scale median (GSM) was used as the collagen content. The degree of calcification was defined by the hematoxylin-eosin stain as follows: "0:" no calcification, "1:" scattered microcalcification, or "2:" calcification greater than 1 mm or more than 2% of the total calcification. Carotid echocardiographic findings, specifically echoluminance or the brightness of the narrowest lesion of the plaque, classified as hypo-, iso-, or hyper-echoic by comparison with the intima-media complex surrounding the plaque, and clinical data were reviewed. RESULTS: Plaque hardness was significantly negatively correlated with GSM [Spearman's correlation coefficient: -0.7137 (p < 0.0001)]: the harder the plaque, the higher the collagen content. There were significant differences between plaque hardness and degree of calcification between "0" and "2" (p = 0.0206). For plaque hardness and echoluminance (hypo-iso-hyper), significant differences were found between hypo-iso (p = 0.0220), hypo-hyper (p = 0.0006), and iso-hyper (p = 0.0015): the harder the plaque, the higher the luminance. In single regression analysis, GSM, sex, and diabetes mellitus were significant variables, and in multiple regression analysis, only GSM was extracted as a significant variable. CONCLUSIONS: Plaque hardness was associated with a higher amount of collagen, which is the main component of the fibrous cap. Greater plaque hardness was associated with increased plaque stability. The degree of calcification may also be associated with plaque hardness.

The diagnostic value of 123I-IMP SPECT in ocular adnexal lymphoma.

BACKGROUND: N-isopropyl- (123I) p-iodoamphetamine (123I-IMP) is specifically accumulated in primary central nervous system lymphoma (PCNSL) during single-photon emission tomography (SPECT) and contributes to its diagnostic imaging. However, whether 123I-IMP is accumulated in ocular adnexal lymphoma (OAL), one of the malignant intraorbital tumors, remains unclear. This study aimed to evaluate the diagnostic value of 123I-IMP SPECT in OAL. METHODS: Between August 2005 and June 2020, 26 patients with intraorbital tumors underwent neurosurgery at the tertiary care center. Of these, 15 patients who underwent 123I-IMPSPECT before surgery were retrospectively examined. The region of interest was set in the cerebellum ipsilateral to the intraorbital tumor on 123I-IMP SPECT, and the tumor-to-cerebellum ratio (T/C ratio) was calculated using the following formula: T/C ratio = [accumulation of tumor (count/pixel)]/[accumulation of ipsilateral normal cerebellar hemisphere (count/pixel)]. RESULTS: Six patients were included in the OAL group, who were pathologically diagnosed with extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), diffuse large B-cell lymphoma (DLBCL), and plasmacytoma. The T/C ratio in the OAL group was statistically higher than that in the non-OAL group (p < 0.01). The optimal cutoff values for both groups were between 0.76 and < 0.93. The sensitivity and specificity were 1.00, respectively. CONCLUSIONS: 123I-IMP SPECT is useful as one of the examinations in the differential diagnoses of OAL, because it showed a significantly higher accumulation in OAL group than in non-OAL group.

[A Case of Mature Teratoma in the Third Ventricle with Holmes Tremor].

Intracranial teratoma is a rare disease that frequently occurs in children and young adults. It comprises of approximately 0.1% of the brain tumors. We report a case of a large mature teratoma in the third ventricle with Holmes tremor. A 5-year-old boy presented with tremors 2 years ago. CT showed a 56×48 mm tumor in the third ventricle and hydrocephalus. The tumor was well demarcated from the surrounding brain tissue and contained calcification. MRI indicated a partially high-intensity signal on T1-weighted and T2-weighted images. The preoperative diagnosis was teratoma. Initially, the tumor was biopsied using neuroendoscopy and the Ommaya reservoir was set. The pathological results showed fat-like tissues and fibroblasts. Subsequently, the tumor was completely removed using the interhemispheric transcallosal transchoroidal approach. The tumor included fat and hair tissues. It also included calcification similar to that observed in a tooth. It was strongly adhered near the pineal gland. Pathologically, the diagnosis was a mature teratoma. Postoperatively, the tremor disappeared and the patient was discharged from the hospital without neurological deficits. We believe that compression of the Guillain-Mollaret triangle was relieved by removal of the tumor. Hence, the tremor disappeared after the operation.

A neurosurgical simulation of skull base tumors using a 3D printed rapid prototyping model containing mesh structures.

BACKGROUND: Deep regions are not visible in three-dimensional (3D) printed rapid prototyping (RP) models prepared from opaque materials, which is not the case with translucent images. The objectives of this study were to develop an RP model in which a skull base tumor was simulated using mesh, and to investigate its usefulness for surgical simulations by evaluating the visibility of its deep regions. METHODS: A 3D printer that employs binder jetting and is mainly used to prepare plaster models was used. RP models containing a solid tumor, no tumor, and a mesh tumor were prepared based on computed tomography, magnetic resonance imaging, and angiographic data for four cases of petroclival tumor. Twelve neurosurgeons graded the three types of RP model into the following four categories: 'clearly visible,' 'visible,' 'difficult to see,' and 'invisible,' based on the visibility of the internal carotid artery, basilar artery, and brain stem through a craniotomy performed via the combined transpetrosal approach. In addition, the 3D positional relationships between these structures and the tumor were assessed. RESULTS: The internal carotid artery, basilar artery, and brain stem and the positional relationships of these structures with the tumor were significantly more visible in the RP models with mesh tumors than in the RP models with solid or no tumors. CONCLUSIONS: The deep regions of PR models containing mesh skull base tumors were easy to visualize. This 3D printing-based method might be applicable to various surgical simulations.