Background/Objectives: Late epilepsy occurring in the late stage after glioblastoma (GBM) resection is suggested to be caused by increased extracellular glutamate (Glu). To elucidate the mechanism underlying postoperative late epilepsy, the present study aimed to investigate the expressions and relations of molecules related to Glu metabolism in tumor tissues from GBM patients and cultured glioma stem-like cells (GSCs). Methods: Expressions of CD44, xCT and excitatory amino acid transporter (EAAT) 2 and extracellular Glu concentration in GBM patients with and without epilepsy were examined and their relationships were analyzed. For the study using GSCs, expressions and relationships of the same molecules were analyzed and the effects of CD44 knock-down on xCT, EAAT2, and Glu were investigated. In addition, the effects of hypoxia on the expressions of these molecules were investigated. Results: Tumor tissues highly expressed CD44 and xCT in the periphery of GBM with epilepsy, whereas no significant difference in EAAT2 expression was seen between groups with and without epilepsy. Extracellular Glu concentration was higher in patients with epilepsy than those without epilepsy. GSCs displayed reciprocal expressions of CD44 and xCT. Concentrations of extracellular Glu coincided with the degree of xCT expression, and CD44 knock-down elevated xCT expression and extracellular Glu concentrations. Hypoxia of 1% O2 elevated expression of CD44, while 5% O2 increased xCT and extracellular Glu concentration. Conclusions: Late epilepsy after GBM resection was related to extracellular Glu concentrations that were regulated by reciprocal expression of CD44 and xCT, which were stimulated by differential hypoxia for each molecule.
Granular cell tumor (GCT) of the sellar region is a rare tumor of the sellar and suprasellar regions that originate from the neurohypophysis. This tumor is very difficult to differentiate from other pituitary neoplasms, such as pituitary adenoma, pituicytoma, and spindle cell oncocytoma. We report a rare case of GCT arising from the posterior pituitary of the sellar region and suggest a useful indicator for accurate diagnosis and pitfalls for surgical procedures.A 42-year-old woman was admitted to our hospital with bitemporal hemianopsia. Neuroimaging showed a large pituitary tumor in the sellar and suprasellar regions with a hypointense part on T2-weighted magnetic resonance imaging, and the enhanced anterior pituitary gland was displaced anteriorly. Laboratory findings showed mild hyperprolactinemia. Subtotal resection of the tumor was achieved using an endoscopic endonasal transsphenoidal approach. Histological findings showed round or polygonal cells with abundant granular eosinophilic cytoplasm staining strongly for thyroid transcription factor 1. The tumor was, therefore, diagnosed as a GCT of the sellar region, belonging to tumors of the posterior pituitary. After surgery, visual impairment and anterior pituitary function were improved. Follow-up neuroimaging after 1 year showed no signs of recurrence.GCT of the sellar region is difficult to diagnose on routine neuroimaging. Therefore, accurate diagnosis requires careful identification of clinical signs, magnetic resonance imaging including hypointensity on T2-weighted imaging, and analysis of combined morphological and immunohistochemical studies.
Purpose . We investigate the usefulness of multimodal assistant systems using a fusion model of preoperative three-dimensional (3D) computed tomography (CT) and magnetic resonance imaging (MRI) along with endoscopy with indocyanine green (ICG) fluorescence in establishing endoscopic endonasal transsphenoidal surgery (ETSS) as a more effective treatment procedure. Methods . Thirty-five consecutive patients undergoing ETSS in our hospital between April 2014 and March 2015 were enrolled in the study. In all patients, fusion models of 3D-CT and MRI were created by reconstructing preoperative images. In addition, in 10 patients, 12.5 mg of ICG was intravenously administered, allowing visualization of surrounding structures. We evaluated the accuracy and utility of these combined modalities in ETSS. Results . The fusion model of 3D-CT and MRI clearly demonstrated the complicated structures in the sphenoidal sinus and the position of the internal carotid arteries (ICAs), even with extensive tumor infiltration. ICG endoscopy enabled us to visualize the surrounding structures by the phasic appearance of fluorescent signals emitted at specific consecutive elapsed times. Conclusions . Preoperative 3D-CT and MRI fusion models with intraoperative ICG endoscopy allowed distinct visualization of vital structures in cases where tumors had extensively infiltrated the sphenoidal sinus. Additionally, the ICG endoscope was a useful real-time monitoring tool for ETSS.
We report the case of a patient who has progressed well over 5 years following single-stage aneurysm clipping and superficial temporal artery-middle cerebral artery(STA-MCA)double anastomoses in the acute phase, for a ruptured distal anterior choroidal artery(AChA)aneurysm accompanied by a twig-like MCA. The patient was a 49-year-old female who developed a sudden severe headache and disturbance of consciousness due to subarachnoid hemorrhage and intraventricular hemorrhage(IVH). Cerebral angiography showed a right twig-like MCA associated with an abnormal vascular network and a ruptured aneurysm in the distal AChA. A day after emergency ventricular drainage for acute hydrocephalus, right frontotemporal craniotomy enabled distal AChA aneurysm clipping, together with removal of the IVH via transchoroidal fissure approach, in addition to STA-MCA double anastomoses to prevent recurrence of hemorrhage. The IVH resolved after surgery and no new infarct area was observed. Cerebral angiography revealed the disappearance of the aneurysm, good patency of the double bypass, and reduction of the abnormal vascular network. The patient gradually recovered without any neurological deficits, except for mild memory disturbance. Five years after the surgery, the patient has experienced no recurrence. The single-stage operation of aneurysm clipping and STA-MCA double anastomoses was made possible by devising an approach for a ruptured cerebral aneurysm, even in the acute stage. The successful improvement of cerebral circulation and prevention of cerebral hemorrhage from an early stage could serve as a reference for the treatment of similar hemorrhagic cases.
Dermoid cysts are rare benign intracranial neoplasms derived from embryonal remnant tissues. Here, we describe a case of dermoid cyst located in the right frontal lobe, which showed repeated changes on CT. An 11-year-old girl was referred to our hospital to treat a brain neoplasm. Brain CT and MRI revealed a cystic tumor in the right frontal lobe. Incidentally, brain CT had been performed 6, 2, and 1 year before the presentation, which demonstrated repeated changes in the tumor over the clinical course. Gross total resection of the tumor was achieved through right frontal craniotomy. Histological findings revealed keratin flakes, mature bones, cholesterol crystals, and granulation with macrophages. The cyst wall was composed of squamous epithelium with adnexal structures, such as hair follicles and sebaceous glands. Therefore, we diagnosed the tumor as a dermoid cyst. The postoperative course was uneventful, and she was discharged on postoperative day 10 without neurological deficits. Dermoid cysts are difficult to be diagnosed on routine neuroimaging. An accurate diagnosis requires details of the clinical course and analysis of both imaging and pathological studies.
Abstract Background: Recognizing the anatomical orientation surrounding the sellar floor is crucial in endoscopic endonasal transsphenoidal surgery (ETSS). Zero-echo-time (ZTE) sequences were recently suggested for a new bone identification technique on magnetic resonance imaging (MRI). This study aimed to evaluate the clinical usefulness of three-dimensional (3D)-ZTE-based MRI models in providing anatomical guidance for ETSS.Methods: ZTE-based MRI and magnetic resonance angiography (MRA) data from 15 consecutive patients with pituitary tumor treated between September 2018 and May 2019 were used to create 3D-MRI models. From these, the architecture surrounding the sellar floor, particularly anatomical relationships between tumors and internal carotid arteries (ICAs), was visualized to preoperatively plan surgical procedures. In addition, 3D-ZTE-based MRI models were compared to actual surgical views during ETSS to evaluate model applicability.Results: These 3D-ZTE-based MRI models clearly demonstrated the morphology of the sellar floor and matched well with intraoperative views, including pituitary tumor, by successively eliminating sphenoidal structures. The models also permitted determination of the maximum marginal line of the opening of the sellar floor by presenting vital structures such as ICAs and tumors. With such 3D-MRI models, the surgeon could access the intracranial area through the sellar floor more safely, and resect the pituitary tumor maximally without complications. Conclusions: Our 3D-MRI models based on ZTE sequences allowed distinct visualization of vital structures and pituitary tumor around the sellar floor. This new method using 3D-ZTE-based MRI models showed low invasiveness for patients and was useful in preoperative planning for ETSS, facilitating maximum tumor resection without complications.
Patients with severe internal carotid artery (ICA) stenosis with multiple medical problems generally undergo carotid artery stenting (CAS). However, it is difficult to perform CAS in some patients because iodinated contrast medium is hard to use. We report a patient with asymptomatic ICA stenosis and chronic renal failure, in whom successful treatment was achieved using CAS with minimal use of iodinated contrast medium. A 68-year-old man with severely chronic renal failure was consulted for treatment of left ICA stenosis. Magnetic resonance angiography (MRA) and carotid echography revealed left ICA severe stenosis, and systemic non-contrast MRA showed left femoral artery constriction, but right femoral artery to be intact. CAS was therefore performed through the right femoral artery, using non-contrast three-dimensional computed tomography (3D-CT) with MRA fusion imaging, intravascular ultrasonography, and a small amount of iodinated low-osmolar contrast medium. Postoperative course was uneventful with no aggravation of renal dysfunction, and he was discharged 7 days postoperatively. These techniques are very useful for patients with chronic renal failure, and this present case represents the first report of CAS treated by using non-contrast 3D-CT with MRA fusion image technique.
Sarcoidosis is a multisystem disorder characterized by noncaseating epithelioid granulomas. However, neurosarcoidosis occurring only in the medulla oblongata is very rare and lacks specific imaging and clinical features. We report a rare case of neurosarcoidosis arising from the medulla oblongata alone, suggesting the significance of pathological findings for accurate diagnosis.A 78-year-old woman with a history of rheumatoid arthritis was admitted to our hospital with a 3-month history of progressive numbness in bilateral lower extremities and gait disturbance. Neurological examination on admission showed mild bilateral paired paralysis of the lower limbs (manual muscle test: right 2/V; left 4/V) and marked numbness in the right lower limb. Neuroimaging revealed a solid mass with clear boundaries in the dorsal medulla oblongata appearing hypointense on T1-weighted imaging (WI), hyperintense on T2-WI, and hypointense on diffusion WI (DWI), with strong enhancement on gadolinium-enhanced T1-WI. Cerebrospinal fluid analysis showed moderately elevated levels of protein and lymphocytic cells. Biopsy to determine the exact diagnosis revealed histological findings of noncaseating epithelioid granulomas and inflammatory infiltration, consistent with sarcoidosis. Postoperatively, corticosteroid therapy with prednisolone was initiated as soon as possible, resulting in marked reductions in lesion size. Follow-up neuroimaging after 12 months showed no signs of recurrence.Neurosarcoidosis is difficult to diagnose from routine neuroimaging and laboratory findings. Accurate diagnosis requires careful identification of clinical signs, hypointensity on DWI, and morphological findings from surgical biopsy.
