Hirotaka Hasegawa

Neoadjuvant nivolumab monotherapy is feasible with an acceptable safety profile and induces a MPR in certain patients with resectable GC. (Registration: clinicaltrials.jp, JapicCTI-183895).

OBJECTIVE Skull base chondrosarcoma is one of the most intractable tumors because of its aggressive biological behavior and involvement of the internal carotid artery and cranial nerves (CNs). One of the most accepted treatment strategies for skull base chondrosarcoma has been surgical removal of the tumor in conjunction with proactive extensive radiation therapy (RT) to the original tumor bed. However, the optimal strategy has not been determined. The goal of this study was to evaluate the earl

The efficacy of radiosurgery for neurofibromatosis type 2 (NF2)-associated vestibular schwannoma (VS) remains debatable. We retrospectively analyzed radiosurgical outcomes for NF2-associated VS compared to sporadic VS using our database of 422 consecutive VS patients. Twenty-five patients with 30 NF2-associated VSs with a mean follow-up of 121 months were identified. NF2-associated VSs exhibited excellent tumor control (10-year cumulative rate, 92% vs. 92% in sporadic VSs; <i>p</i> = 0.945) and

OBJECTIVEIn Gamma Knife radiosurgery (GKS) for arteriovenous malformations (AVMs), CT angiography (CTA), MRI, and digital subtraction angiography (DSA) are generally used to define the nidus. Although the AVM angioarchitecture can be visualized with superior resolution using rotational angiography (RA), the efficacy of integrating RA into the GKS treatment planning process has not been elucidated.METHODSUsing data collected from 25 consecutive patients with AVMs who were treated with GKS at the

GTR/NTR seems to contribute to better disease control without significantly impairing functional status. Initial resection offers the best chance to achieve better EOR, leading to better disease control.

Gamma Knife radiosurgery (GKRS) has long been used for treating brain vascular malformations, including arteriovenous malformations (AVMs), dural arteriovenous fistulas (DAVFs), and cavernous malformations (CMs). Herein, current evidence and controversies regarding the role of stereotactic radiosurgery for vascular malformations are described. 1) It has already been established that GKRS achieves 70-85% obliteration rates after a 3-5-year latency period for small to medium-sized AVMs. However, l

SRS is one of the standard therapies for meningiomas in elderly patients, providing both favorable tumor control and a low risk of adverse events under minimum invasiveness.

It is debated whether the efficacy and long-term safety of gamma knife radiosurgery (GKRS) for arteriovenous malformations (AVMs) differs between adult and pediatric patients. We aimed to clarify the long-term outcomes of GKRS in pediatric patients and how they compare to those in adult patients. We collected data for 736 consecutive patients with AVMs treated with GKRS between 1990 and 2014 and divided the patients into pediatric (age < 20 years, n = 144) and adult (age ≥ 20 years, n = 592) coh

Acute internal carotid artery (ICA) terminus occlusion is associated with extremely poor functional outcomes or mortality, especially when it is caused by plaque rupture of the cervical ICA with engrafted thrombus that elongates and extends into the ICA terminus. The goal of this study was to evaluate the efficacy and safety of surgical embolectomy in conjunction with carotid endarterectomy (CEA) for acute ICA terminus occlusion associated with cervical plaque rupture resulting in tandem occlusi

The outcomes for large AVMs were generally favorable when treated with ablative doses. Single-session SRS could be acceptable for AVMs up to ≈20 mL if treated with ablative doses.

A procedure for lateral approach to the ventral portion of the foramen magnum and the upper cervical canal is described. The patient was placed in the lateral position and a curvilinear skin incision was made from the retoroauricular area down to the lateral neck across the sternocleidomastoid muscle, and underlying muscle layers were divided. A suboccipital hemicraniotomy and hemilaminectomies were performed with an air drill. Because the medulla and the cervical cord are displaced posteriorly