Atypical venous drainage system and distinct vascular characteristics in pediatric intracerebral hemorrhage caused by multiple micro arteriovenous malformations.

BACKGROUND: Hemorrhagic brain micro-arteriovenous malformations (micro-AVMs) are considered to constitute a relatively significant portion of pediatric AVMs, though they are often associated with a low bleeding rate, as seen in hereditary hemorrhagic telangiectasia, which frequently involves multiple micro-AVMs. We present a rare case of a 10-year-old girl with multiple hemorrhagic micro-AVMs. Intraoperative findings during the emergency operation for hematoma evacuation and post-operative superselective angiography highlighted the unique angioarchitecture of three micro-AVMs (two lesions in the superficial areas and one lesion in the deep-seated area) and the atypical bleeding source due to the complex congestive venous drainage system. One micro-AVM was successfully occluded by a transarterial emboliozation, and remaining two micro-AVMs underwent gamma knife irradiation as a salvage therapy. CONCLUSION: Superselective angiography is crucial for detecting micro-AVMs, offering detailed insights into small, localized abnormal vascular drainage systems, and guiding therapeutic strategy. Additionally, micro-AVM-associated unique vascular hypersensitivity, such as vasospasm, requires careful consideration, as invasive procedures may significantly alter the visibility of the entire micro-AVM network.

A retrospective cohort study of stereotactic radiosurgery for vestibular schwannomas: Comparison of two age groups (75 years or older vs. 65-74 years).

Background: Treatment outcome data of stereotactic radiosurgery (SRS) for vestibular schwannomas (VS) in patients ≥75 years (late elderly) are lacking. Approximately 39% of patients ≥75 years with VS were reported to experience severe facial palsy after surgical removal. This study compared the treatment outcomes post-SRS for VS between patients ≥75 and 65-74 years (early elderly). Methods: Of 453 patients who underwent gamma knife SRS for VS, 156 were ≥65 years old. The late and early elderly groups comprised 35 and 121 patients, respectively. The median tumor volume was 4.4 cc, and the median radiation dose was 12.0 Gy. Results: The median follow-up periods were 37 and 56 months in the late and early elderly groups, respectively. Tumor volume control was observed in 27 (88%) and 95 (83%) patients (P = 0.78), while additional procedures were required in 2 (6%) and 6 (6%) patients (P = 1.00) in the late and early elderly groups, respectively. At the 60th and 120th months post-SRS, the cumulative tumor control rates were 87%, 75%, 85%, and 73% (P = 0.81), while the cumulative clinical control rates were 93% and 87%, 95%, and 89% (P = 0.80), in the late and early elderly groups, respectively. In the early elderly group, two patients experienced facial pain, and one experienced facial palsy post-SRS; there were no adverse effects in the late elderly group (both P = 1.00). Conclusion: SRS is effective for VS and beneficial in patients ≥75 years old as it preserves the facial nerve.

[Preoperative Simulation of Endoscopic Endonasal Approach for Craniopharyngiomas or Tuberculum Sellae Meningiomas].

Preoperative simulation for endoscopic endonasal approach(EEA)using computed tomography and magnetic resonance imaging evaluates tumor extension and the relationship between adjacent structure(the pituitary stalk, major vessels, and cranial nerves); therefore, preoperative planning of nasal procedure, skull base bony removal, and cranial base reconstruction are possible. Additionally, three-dimensional(3D)fusion image aids surgeons to visualize intraoperative 3D findings. These preoperative simulations are critical to avoid complications and predict pitfalls perioperatively. However, tumor consistency or adhesion with adjacent structure cannot be predicted but is judged perioperatively, which affects the extent of tumor resection. This manuscript describes important points of preoperative simulation for EEA, especially the transplanum-transtuberculum approach for craniopharyngiomas or tuberculum sellae meningiomas, showing some examples in patients.

Rise of oligodendroglioma hypermutator phenotype from a subclone harboring TP53 mutation after TMZ treatment.

Oligodendrogliomas characterized and defined by 1p/19q co-deletion are slowly growing tumors showing better prognosis than astrocytomas. TP53 mutation is rare in oligodendrogliomas while the vast majority of astrocytomas harbor the mutation, making TP53 mutation mutually exclusive with 1p/19q codeletion in lower grade gliomas virtually. We report a case of 51-year-old woman with a left fronto-temporal oligodendroglioma that contained a small portion with a TP53 mutation, R248Q, at the initial surgery. On a first, slow-growing recurrence 29 months after radiation and nitrosourea-based chemotherapy, the patient underwent TMZ chemotherapy. The recurrent tumor responded well to TMZ but developed a rapid progression after 6 cycles as a malignant hypermutator tumor with a MSH6 mutation. Most of the recurrent tumor lacked typical oligodendroglioma morphology that was observed in the primary tumor, while it retained the IDH1 mutation and 1p/19q co-deletion. The identical TP53 mutation observed in the small portion of the primary tumor was universal in the recurrence. This case embodied the theoretically understandable clonal expansion of the TP53 mutation with additional mismatch repair gene dysfunction leading to hypermutator phenotype. It thus indicated that TP53 mutation in oligodendroglioma, although not common, may play a critical role in the development of hypermutator after TMZ treatment.

Risk Factors for Radiation Necrosis and Local Recurrence after Proton Beam Therapy for Skull Base Chordoma or Chondrosarcoma.

[Proposal] Here, we retrospectively evaluate risk factors for radiation necrosis and local recurrence after PBT for skull base chordoma or chondrosarcoma. [Patients and Methods] We analyzed 101 patients who received PBT for skull base chordomas and chondrosarcomas from January 1989 to February 2021. Multivariable logistic regression models were applied for local recurrence, temporal lobe radiation necrosis rates, and temporal lobe radiation necrosis. [Results] In multivariate analysis, chordoma and large tumor size were independent significant factors for local recurrence. The 1-, 2-, 3-, 4- and 5-year local recurrence rates were 3.9%, 16.9%, 20.3%, 28.5% and 44.0% for chordoma and 0%, 0%, 0%, 0% and 7.1% for chondrosarcoma, respectively. The local recurrence rates of small tumors (<30 mm) were 4.3%, 14.7%, 17.7%, 17.7% and 25.9%, and those for large tumors were 3.6%, 15.1%, 19.2%, 32.7% and 59.6%, respectively. In multivariate analysis, BED Gy10 and total dose were risk factors for radiation necrosis. [Conclusions] For skull base chordoma and chondrosarcoma, the risk factors of local recurrence were chordoma and large tumor size, and those of radiation necrosis were BED Gy10 and total dose, respectively. DVH analysis is needed to investigate the risk factors for brain necrosis in more detail.

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.

[Epidemiology, Genetics and Pathophysiology of Pituitary Tumors].

Pituitary tumors or tumors of the sella turcica include pituitary neuroendocrine tumors, Rathke's cleft cysts, craniopharyngiomas, tuberculum sellae, planum sphenoidale meningiomas, germ cell tumors, and hypophysitis. In addition, some rare tumors, such as pituicytomas, granular cell tumors, spindle cell oncocytomas, and chordomas or chondrosarcomas, arise from the parasellar regions. The treatment strategy is completely different for each lesion; therefore, accurate diagnosis is essential.

Differentiation of silent corticotroph pituitary neuroendocrine tumors (PitNETs) from non-functioning PitNETs using kinetic analysis of dynamic MRI.

PURPOSE: Silent corticotroph pituitary adenomas (SCAs)/pituitary neuroendocrine tumors (PitNETs) are common non-functioning pituitary adenomas (NFAs)/PitNETs with a clinically aggressive course. This study aimed to investigate the ability of time-intensity analysis of dynamic magnetic resonance imaging (MRI) for distinguishing adrenocorticotropic hormone (ACTH)-positive SCAs and ACTH-negative SCAs from other NFAs. MATERIALS AND METHODS: We retrospectively evaluated the dynamic MRI findings of patients with NFAs. The initial slope of the kinetic curve (slopeini) obtained by dynamic MRI for each tumor was analyzed using a modified empirical mathematical model. The maximum slope of the kinetic curve (slopemax) was obtained by geometric calculation. RESULTS: A total of 106 patients with NFAs (11 ACTH-positive SCAs, 5 ACTH-negative SCAs, and 90 other NFAs) were evaluated. The kinetic curves of ACTH-positive SCAs had significantly lesser slopeini and slopemax compared with ACTH-negative SCAs (P = 0.040 and P = 0.001, respectively) and other NFAs (P = 0.018 and P = 0.035, respectively). Conversely, the slopeini and slopemax were significantly greater in ACTH-negative SCAs than in NFAs other than ACTH-negative SCAs (P = 0.033 and P = 0.044, respectively). In receiver operating characteristic analysis of ACTH-positive SCAs and other NFAs, the area under the curve (AUC) values for slopeini and slopemax were 0.762 and 0748, respectively. In predicting ACTH-negative SCAs, the AUC values for slopeini and slopemax were 0.784 and 0.846, respectively. CONCLUSIONS: Dynamic MRI can distinguish ACTH-positive SCAs and ACTH-negative SCAs from other NFAs.

Endoscopic transoral resection for an upper cervical chordoma in a pediatric patient.

BACKGROUND: Upper cervical chordoma (UCC) is a rare disease, and although transoral approaches are the methods of choice, minimally invasive techniques have not been established. METHOD: We report the successful use of endoscopic transoral surgery for upper cervical chordoma at the C1-3 levels in the midline epidural space in an 8-year-old girl who presented with neck pain and quadriplegia. Three months after occipitocervical posterior fixation, endoscopic transoral surgery was performed and the tumor was nearly totally removed. CONCLUSION: Endoscopic transoral surgery in pediatric patients with UCCs is a minimally invasive and safe technique.

Successful Treatment of Basaloid Squamous Cell Carcinoma of the Nasal Cavity With Brain Invasion.

Basaloid squamous cell carcinoma (BSCC) is a rare and aggressive subtype of squamous cell carcinoma (SCC). To date, no consensus on the treatment of BSCC has been established yet, especially in cases of invasion of the skull base. In addition, long-term prognosis has not been reported in T4b cases. Herein, we report the case of a 36-year-old Japanese man with locally advanced nasal BSCC that directly invaded the skull base and the brain. The patient was then treated with induction chemotherapy (IC). Owing to his good response to IC, we planned and performed en bloc resection followed by adjuvant proton beam therapy (PBT). Follow-up examinations five years after treatment showed no evidence of recurrence. This is the first report of IC followed by radical surgery and adjuvant PBT in a patient with T4b. IC has the potential to play an important role in treatment strategies.