A novel radiological research field pursuing comprehensive quantitative image, namely “Radiomics,” gained traction along with the advancement of computational technology and artificial intelligence. This novel concept for analyzing medical images brought extensive interest to the neuro-oncology and neuroradiology research community to build a diagnostic workflow to detect clinically relevant genetic alteration of gliomas noninvasively. Although quite a few promising results were published regarding MRI-based diagnosis of isocitrate dehydrogenase (IDH) mutation in gliomas, it has become clear that an ample amount of effort is still needed to render this technology clinically applicable. At the same time, many significant insights were discovered through this research project, some of which could be “reverse engineered” to improve conventional non-radiomic MR image acquisition. In this review article, the authors aim to discuss the recent advancements and encountering issues of radiomics, how we can apply the knowledge provided by radiomics to standard clinical images, and further expected technological advances in the realm of radiomics and glioma.

Moyamoya disease (MMD) causes intracranial arterial stenosis progression. The progression of intracranial arterial stenosis will increase the risk of ischemic cerebrovascular events. This study aims to investigate the relationship between intracranial arterial stenosis progression, vessel wall enhancement (VWE), and the recent neurological symptoms. A total of 39 MMD patients (12 male; 37.6 ± 18.0 years old) were registered in this study analysis between April 2016 and July 2018. All patients received MRI at registration and 6, 12, and 24 months post-registration. The incidence of ischemic cerebrovascular events (transit ischemic attacks or cerebral infarction) was checked until December 2018. We evaluated the relationship between the intensity of VWE, intracranial arterial stenosis, and the recent neurological symptoms. During the mean follow-up period of 13.8 ± 5.5 months, the changes in VWE were observed in 33 hemispheres (42.3%), stenosis progression was observed in 21 hemispheres (26.9%), and recent neurological symptoms occurred in 10 hemispheres (12.8%). Stenosis progression was observed in 11 hemispheres (33.3%) in the VWE(+) group and ten hemispheres (22.2%) in the VWE(−) group (p = 0.310). The recent neurological symptoms were observed in eight hemispheres (21.2%) in the VWE(+) group and two hemispheres (4.44%) in the VWE(−) group (odds ratio 6.88, 95% confidence interval 1.35–34.98, p = 0.015). The intensity of VWE sometimes changes. The changes in VWE were significantly associated with the recent neurological symptoms but not with stenosis progression.

Various approaches have been tried for acute ischemic stroke (AIS) treatment to shorten the time from onset to recanalization. MRI positioning scanning (PS), which must be taken before any MRI sequences, was examined whether it can detect cerebral large vessel occlusion. A total of 68 consecutive patients with AIS who underwent MRI and were treated with intravenous recombinant tissue plasminogen activator or mechanical thrombectomy at our hospital were retrospectively included in this study. Occluded vessels were identified on the axial or coronal views of PS images, and these images were compared with 3D time-of-flight MRA and digital subtraction angiogram. The sensitivities, positive predictive values (PPVs), and negative predictive values (NPVs) for internal carotid artery (ICA), the proximal M1, distal M1, and M2 segment of the middle cerebral artery occlusion were assessed, and the number of PS slices was assessed. The sensitivities of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 62%, 21%, 35%, and 86%, respectively. The PPVs of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 81%, 88%, 100%, and 97%, respectively, and the NPVs of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 94%, 90%, 86%, and 100%, respectively. The detection rate for the ICA was significantly higher with three axial slices (91%) than with two slices (47%) (p <0.01). MRI PS is warranted to be referred to detect large cerebral vessel occlusion.

This study aimed to examine the beneficial effects of a novel prophylactic barbiturate therapy, step-down infusion of barbiturates, using thiamylal with normothermia (NOR+sdB), on the poor outcome in the patients with severe traumatic brain injuries (sTBI), in comparison with mild hypothermia (MD-HYPO). From January 2000 to March 2019, 4133 patients with TBI were admitted to our hospital. The inclusion criteria were: a Glasgow coma scale (GCS) score of ≤8 on admission, age between 20 and 80 years, intracranial hematoma requiring surgical evacuation of the hematoma with craniotomy and/or external decompression, and patients who underwent management of body temperature and assessed their outcome at 6–12 months. Finally, 43 patients were included in the MD-HYPO (n = 29) and NOR+sdB (n = 14) groups. sdB was initiated intraoperatively or immediately after the surgical treatment. There were no significant differences in patient characteristics, including age, sex, past medical history, GCS on admission, type of intracranial hematoma, and length of hospitalization between the two groups. Although NOR+sdB could not improve the patient’s poor outcome either at discharge from the intensive care unit (ICU) or at 6–12 months after admission, the treatment inhibited composite death at discharge from the ICU. The mean value of the maximum intracranial pressure (ICP) in the NOR+sdB group was <20 mmHg throughout the first 120 h. NOR+sdB prevented composite death in the ICU in patients with sTBI, and we may obtain novel insights into the beneficial role of prophylactic barbiturate therapy from suppression of the elevated ICP during the first 120 h.

Clinical trial data of Carmustine implant (Gliadel Wafer) in Japanese patients with malignant glioma are limited; thus, we conducted a postmarketing surveillance study to evaluate the safety of Gliadel in real-world clinical practice in Japan. In this postmarketing surveillance study, all patients who received Gliadel placement for malignant glioma surgeries from its market launch (January 9, 2013) to July 10, 2013 were enrolled from 229 institutions using a central registration system. Up to eight wafers of Gliadel (containing 61.6 mg of carmustine) were used to cover the site of brain tumor resection intraoperatively according to the size and shape of the tumor resection cavity. The observation period lasted 3 months after Gliadel placement. Patients were followed up for 1 year postoperatively. Safety was assessed by the incidence of adverse events (AEs) and adverse drug reactions (ADRs). In total, 558 patients were included. Most patients (66.7%) received eight Gliadel wafers. The percentage of patients with ADRs was 35.7% (365 ADR episodes in 199 patients). Of the AEs of special interest, the most common were cerebral edema (22.2%, 124/558 patients), convulsion (9.9%, 55/558 patients), impaired healing (4.8%, 27/558 patients), and infection (3.4%, 19/558 patients). This first all-case postmarketing surveillance report of the safety of Gliadel in real-world clinical practice in Japan suggests that the risk of toxicity with Gliadel placement is relatively tolerable. The survival benefits of Gliadel placement should be evaluated and considered carefully by the clinician taking into account possible toxicities.

We developed a new cranioplasty method that utilizes artificial bone made of ultra-high-molecular-weight polyethylene, with a wedge-shaped edge (UHMWPE Wing). This study shows the methods and data of case series and finite element analyses with the UHMWPE Wing. A circumferential wing was preoperatively designed for a custom-made artificial bone made of UHMWPE to achieve high fixed power and to minimize the usage of cranial implants. Here, we present 4 years of follow-up data and finite element analyses for patients treated with the UHMWPE Wing between February 2015 and February 2019. Eighteen consecutive patients underwent cranioplasty using our UHMWPE Wing design. There were no postoperative adverse events in 17 of the patients for at least 18 months. One case of hydrocephalus experienced screw loosening and graft uplift due to shunt malfunction. Placement of a ventriculo-peritoneal shunt immediately returned the artificial bone to normal position. Finite element analyses revealed that a model using the UHMWPE Wing had the highest withstand load and lowest deformation. This is the first report on the UHMWPE Wing method. This method may enable clinicians to minimize dead space and achieve high strength in cranioplasty.

Extensive traumatic anterior skull base fractures from the frontal sinus to the parasellar region are frequently accompanied by multiple dural defects that cause persistent cerebrospinal fluid (CSF) leakage. Conventional transcranial reconstruction using a frontal periosteal flap is frequently insufficient, and parasellar dural defects are often deep, complex, and difficult to identify. In this report, we describe a combined transcranial–endonasal reconstructive technique and report our experience. Simultaneous combined transcranial and endoscopic surgery was performed in three patients with CSF leakage resulting from traumatic anterior skull base fractures. Dural defects were thoroughly identified from the transcranial and endonasal surgical fields, and covered using a multilayer sealing technique. The anterior regions of the anterior skull base were reconstructed using a free fascial flap and frontal periosteal flap; posterior and parasellar regions were reconstructed using a fat graft, vascularized nasoseptal flap, and endonasal balloon. Suturing the transcranial grafts to the parasellar dura mater was performed collaboratively by the transcranial and endonasal surgeons. In our cases, complete cessation of CSF leakage was achieved without perioperative lumbar drainage in all patients. Mean time to postoperative ambulation was 7 days (range, 3–11). No surgical complications occurred. Simultaneous transcranial and endonasal procedures were helpful to detect all sites of CSF leakage and secure reconstructive grafts. The combined transcranial and endonasal reconstructive technique achieved secure skull base reconstruction without recurrence of CSF leakage, and allowed early postoperative ambulation. This technique can be a reliable surgical option to repair CSF leakage resulting from extensive anterior skull base fractures.