Clinical outcome, radiological findings, and genetic features of IDH-mutant brainstem glioma in adults.

BACKGROUND: With the recent advent of genetic testing, IDH-mutant glioma has been found among adult brainstem gliomas. However, the clinical outcome and prognosis of IDH-mutant brainstem gliomas in adults have not been elucidated. This study aimed to investigate the clinical outcome, radiological findings, and genetic features of adult patients with IDH-mutant diffuse brainstem gliomas. METHODS: Data from adult patients with brainstem glioma at Hokkaido University Hospital between 2006 and 2022 were retrospectively analyzed. Patient characteristics, treatment methods, genetic features, and prognosis were evaluated. RESULTS: Of 12 patients with brainstem glioma with proven histopathology, 4 were identified with IDH mutation. All patients underwent local radiotherapy with 54 Gray in 27 fractions combined with chemotherapy with temozolomide. Three patients had IDH1 R132H mutation and one had IDH2 R172G mutation. The median progression-free survival and overall survival were 68.4 months and 85.2 months, respectively, longer than that for IDH-wildtype gliomas (5.6 months and 12.0 months, respectively). At the time of initial onset, contrast-enhanced lesions were observed in two of the four cases in magnetic resonance imaging. CONCLUSION: As some adult brainstem gliomas have IDH mutations, and a clearly different prognosis from those with IDH-wildtype, biopsies are proactively considered to confirm the genotype.

Carotid Endarterectomy for a Case with an Extremely Twisted Internal Carotid Artery.

The internal carotid artery (ICA) typically runs posterolaterally to the external carotid artery (ECA) at the level of the common carotid artery (CCA) bifurcation in the neck. The "twisted ICA" is an anatomical variation, wherein the ICA is medial to the ECA. Several studies on the twisted ICA have discussed its anatomical definition, incidence, clinical features, and surgical results in patients with luminal stenosis. Computed tomography angiography (CTA)-based analyses of surgically treated cohorts documented a twist angle, reaching up to 95°. Carotid endarterectomy (CEA) was successfully performed for these patients. This study reports a case of a significantly twisted ICA with severe luminal stenosis that was successfully treated with CEA. An 81-year-old male was incidentally diagnosed with asymptomatic right ICA stenosis based on magnetic resonance (MR) angiography. Three-dimensional (3D)-CTA showed that the ICA revealed 74% stenosis of the ICA, based on the North American Symptomatic Carotid Endarterectomy Trial criteria. The 3D-CTA showed the ICA medial to the ipsilateral ECA at the level of the CCA bifurcation in the neck. It extended proximally to the pharynx, and the twist angle was 102°. Black-blood MR of the carotid plaque exhibited a high intensity on T1-weighted imaging, indicating vulnerability. Intraoperatively, the position of the ICA was corrected using multiple hooks instead of a surgical retractor. He showed no permanent deficits, such as an ipsilateral cerebral infarction, although transient postoperative hoarseness was observed. This case report documented a significantly twisted ICA with luminal stenosis, successfully treated via CEA, by correcting the carotid position using multiple hooks with gentle manipulation.

Slow-growing WNT medulloblastoma with atypical magnetic resonance imaging findings: illustrative case.

BACKGROUND: Medulloblastomas, with four molecular subgroups, are generally rapid-growing tumors with significant contrast enhancement and well-defined margins. However, each subgroup's clinical features, including disease time course and imaging characteristics, are not well defined. OBSERVATIONS: The authors describe the case of a 15-year-old female who presented with a 7-month history of impaired left-hand movement and was found to have a lesion on the dorsal side of the fourth ventricle. T2-weighted magnetic resonance imaging (MRI) at the patient's first presentation showed diffuse hyperintense signal without apparent mass, and gadolinium-enhanced T1-weighted imaging showed very slight contrast enhancement. In 1 month, her symptoms progressed, and follow-up MRI revealed an increase in the size of the lesion, showing greater diffusion restriction and contrast enhancement. She underwent gross-total resection, and pathology was consistent with classic medulloblastoma. Genetic analysis of the tumor confirmed the wingless (WNT) molecular subgroup. Adjuvant chemotherapy and proton beam therapy were performed. At the 18-month follow-up, MRI showed no recurrence of disease. LESSONS: Slow-growing medulloblastoma is very rare and not known to be associated with a specific molecular subgroup. Here, the authors report a case of slow-growing WNT medulloblastoma, indicating that slow growth may be a feature of this subgroup.

Transferring neurointerventionalists saves time compared with interhospital transfer of stroke patients for endovascular thrombectomy: a collaborative pooled analysis of 1001 patients (EVEREST).

BACKGROUND: Interhospital transfer of stroke patients (drip and ship concept) is associated with longer treatment times compared with primary admission to a comprehensive stroke center (mothership concept). In recent years, studies on a novel concept of performing endovascular thrombectomy (EVT) at external hospitals (EXT) by transferring neurointerventionalists, instead of patients, have been published. This collaborative study aimed at answering the question of whether EXT saves time in the workflow of acute stroke treatment across various geographical regions. METHODS: This was a patient level pooled analysis of one prospective observational study and four retrospective cohort studies, the EVEREST collaboration (EndoVascular thrombEctomy at Referring and External STroke centers). Time from initial stroke imaging to EVT (vascular puncture) was compared in mothership, drip and ship, and EXT concepts. RESULTS: In total, 1001 stroke patients from various geographical regions who underwent EVT due to large vessel occlusion were included. These were divided into mothership (n=162, 16.2%), drip and ship (n=458, 45.8%), and EXT (n=381, 38.1%) cohorts. The median time periods from onset to EVT (195 min vs 320 min, p<0.001) and from imaging to EVT (97 min vs 184 min, p<0.001) in EXT were significantly shorter than for drip and ship thrombectomy concept. CONCLUSIONS: This pooled analysis of the EVEREST collaboration adds evidence that performing EVT at external hospitals can save time compared with drip and ship across various geographical regions. We encourage conducting randomized controlled trials comparing both triage concepts.

[A Case of Positional Vertebral Artery Occlusion due to Physiological Cervical Extension with Occipital Condylar Spur].

Positional vertebral artery occlusion(PVAO)is a mechanical occlusion of the extracranial vertebral artery(VA)due to physiological movement of the head and neck. However, only a few cases of mechanical VA compression due to routine flexion-extension of the neck have been reported. We present a unique case of PVAO due to neck extension with an occipital condylar spur. A 78-year-old man was admitted to our hospital for sudden onset of right hemiparesis and dysarthria. Magnetic resonance imaging(MRI)revealed bilateral occipital and cerebellar infarctions and vessel occlusion extending from the VA to the basilar artery. Mechanic thrombectomy resulted in partial recanalization. Computed tomography angiography(CTA)performed the next day showed spontaneously recanalized left VA with some wall irregularity. CTA in the neck-extended position revealed a severely compressed left VA in its V3 segment, which was attributed to the left occipital condylar spur with degenerative changes of the condyle-C1 facet. Cervical MRI also showed a pseudotumor from the lower clivus to the odontoid process that indicated mechanical stress on the occipitocervical ligaments. An occiput to C2 fusion was performed to stabilize and avoid dynamic vascular compression. Postoperative CTA revealed no evidence of restricted flow with flexion or extension movements of the neck. It should be noted that physiological head and neck movements accompanied by condylar degenerative changes could be a cause of vertebrobasilar insufficiency.

Long-Term Clinical Outcome and Prognosis After Thrombectomy in Patients With Concomitant Malignancy.

Endovascular thrombectomy (EVT) is the preferred treatment strategy for patients with acute ischemic stroke (AIS). However, clinical outcome and prognosis in patients who undergo EVT in response to AIS with concomitant malignancy have not been fully elucidated. Data of patients with malignancy who underwent EVT at participating institutions between January 2015 and April 2019 were retrospectively analyzed. Patient characteristics, treatment methods, posttreatment strategy, and long-term prognosis were evaluated in 12 patients with prediagnoses of malignancy. Good revascularization (TICI 2b or higher) was achieved in 10 of 12 patients. Among the eight patients who survived more than 2 weeks from onset, four patients showed good clinical outcome [modified Rankin Scale (mRS) <2] at 60 days posttreatment and were able to continue treatment for malignancy. However, seven of eight patients died within a year of EVT (median survival, 83 days) due to progression of malignancy. One-year survival was achieved in only one patient whose etiology of stroke was determined as infectious endocarditis and not Trousseau syndrome. Even after successful revascularization and good short-term clinical outcome, the long-term prognosis after thrombectomy in patients with malignancy was poor. Thrombectomy for concomitant malignancy requires judicious decision, and further studies are necessary to fully elucidate its efficacy.

Rare Case of Spinal Dural Arteriovenous Fistula with Radiculopathy, without Myelopathy or Spinal Edema on Magnetic Resonance Imaging.

BACKGROUND: Spinal dural arteriovenous fistulas (SDAVFs) are the most common type of spinal arteriovenous malformations; they frequently cause progressive myelopathy including gait disturbances and sensory disorders. CASE DESCRIPTION: We report a rare case of a middle-aged man who experienced right-sided chest pain and Th4 radiculopathy, without any other neurologic presentations. Magnetic resonance imaging showed a flow void sign on the dorsal aspect of the spinal cord; spinal angiography revealed an arteriovenous shunt between a radicular artery and an intradural vein. Suspecting SDAVF as the cause of the chest pain, we performed surgical resection. Intraoperatively, we observed compression of the rootlet by the draining vein. Right chest pain disappeared completely after obliteration of the SDAVF. The present patient had vascular compression of the spinal nerve rootlet without any venous congestion. CONCLUSIONS: Our experience shows that SDAVF can present not only as a myelopathy but also as a radiculopathy, indicating that radiculopathy may become a main symptom of SDAVF.

A Rare Case of Idiopathic Temporal Muscle Abscess in a Nine-month-old Infant.

Temporal muscle abscess in children usually occurs from acute otitis media, and rapid progression and concomitant infectious disease often make it easy to diagnose. We report a rare case of a nine-month-old infant who showed right temporal mass with no evidence of infection. Computed tomography showed an osteolytic round mass, and magnetic resonance imaging revealed heterogenous enhancement with a high apparent diffusion coefficient. Malignant tumor was first suspected, but an open biopsy revealed the swelling to be temporal muscle abscess. It should be noted that temporal abscess may mimic the features of a malignant tumor, and multiple examinations should be performed for an accurate diagnosis.