Publications by authors named "Yasutaka Imada"

Article Synopsis
  • The sylvian fissure stem and its deep cisternal part (SDCP) primarily include the orbital gyrus and the front part of the temporal lobe, and their adhesions can complicate surgical approaches.
  • The study categorized SDCP morphology in 81 patients into tight, moderate, and loose types based on arachnoid membrane adhesion and analyzed features via intraoperative videos.
  • Findings indicated that tighter adhesions correlated with larger orbital gyri and younger patients, and the degree of adhesion affected the width of the subarachnoid space, which is important for planning safe surgical approaches.
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In the interhemispheric approach (IHA) for the distal anterior cerebral artery (DACA) aneurysms, the surgical trajectory to a DACA aneurysm is very important because surgeons sometimes encounter the intraoperative disorientation and the premature rupture. The purpose of this study was to clarify the anatomical landmarks indicating the trajectory to the genu of the corpus callosum (GCC) at the early stage of dissection for the correct intraoperative orientation. "Point A" was defined as the crossing point between the frontal bone and the line connecting the projected external acoustic opening (EAO) and the GCC on the midline slice of the sagittal three-dimensional computed tomography angiography (3D-CTA) images.

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Article Synopsis
  • The superficial middle cerebral vein (SMCV) is crucial for opening the sylvian fissure during surgery, and understanding its structure can enhance surgical outcomes.
  • A study analyzed SMCVs in 116 patients using intraoperative videos to classify them into five morphological types, revealing variations in bridging veins between different veins.
  • The findings suggest that recognizing these SMCV types can lead to optimal dissection techniques, minimizing the risk of venous infarction and improving the effectiveness of the trans-sylvian approach.
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The medial frontal cortex (MFC) is a part of the medial surface of the frontal lobe situated in the rostral portion of the corpus callosum (CC). In a surgical interhemispheric approach (IHA), the MFC covers the anterior communicating artery (Aco) complex until the final stage of dissection. To clarify the anatomical relationship between the MFC and the Aco complex, and to facilitate orientation in IHA, we analyzed the morphological features of the MFC in number, size, and pattern of gyri from the medial surface of the hemisphere in the subcallosal portion using 53 adult cadaveric hemispheres.

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In this study, we used 45 adult cadaveric cerebral hemispheres to investigate the anatomical classification of the superficial middle cerebral vein (SMCV) based on the number of stems, course, and anastomosis at the distal portion. We classified the SMCVs into five types based on embryological concept. Type A (18 cases, 40.

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Chronic subdural hematomas (CSDHs) occur often in elderly persons and can occur with mild head trauma. With burr-hole irrigation as standard treatment, symptoms usually improve and can be cured, and outcomes are good, but postoperative recurrences are a common problem. This study investigated the effectiveness and recurrence rates when using artificial cerebrospinal fluid (ACF) instead of normal saline (NS) as an irrigation solution for burr-hole irrigation in patients with CSDH.

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Familial cerebral cavernous malformations (FCCM) are autosomal-dominant vascular malformations. At present, 3 cerebral cavernous malformation genes (KRIT1/CCM1, MGC4607/CCM2, and PDCD10/CCM3) have been identified. Few genetic analyses of Japanese FCCM have been reported.

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The objectives of this study were to elucidate the normal anatomy of middle cerebral artery (MCA) bifurcations and to analyze the differences in patients with MCA aneurysms. In the present study, 62 patients underwent three-dimensional magnetic resonance angiography, and no intracranial lesions were noted. The widths of M1 and the superior and inferior M2 branches, as well as their respective lateral angles, were measured.

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Method: We followed a two-step surgical strategy using miniature Ommaya's reservoirs in an early neonate with multiple large arachnoid cysts.

Conclusion: Percutaneous fluid aspiration through the reservoirs placed during the first operation permitted the infant to develop sufficiently to withstand the second, more radical cyst wall excision.

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The authors report a rare case of petrotentorial meningioma presenting as acute subdural hematoma. A 60-year-old female was introduced to our hospital complaining of sudden headache and gait disturbance. CT and MRI demonstrated a petrotentorial tumor with a subdural hematoma in the posterior fossa.

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The authors report an atypical case of symptomatic entirely suprasellar Rathke's cleft cyst mimicking suprasellar arachnoid cyst. A 55-year-old male was introduced to our hospital complaining of bitemporal hemianopsia. CT and MRI demonstrated a cystic mass located entirely in the suprasellar cistern and to compress the optic nerve and mammillary body.

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Hemangioendothelioma (HE) is an uncommon vascular tumor that is intermediate in histological appearance between a hemangioma and an angiosarcoma. Presently, it is regarded as endothelial tumors of low-grade or intermediate malignancy. It has been reported in the liver, lung, heart, mediastinum, lymph nodes, extremity, and bone.

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Treatment of ruptured dissecting aneurysm of basilar trunk (BADAN) has been controversial yet. We report a case of ruptured BADAN successfully treated with endovascular occlusion of the bilateral vertebral artery (VA) proximal to posterior inferior cerebellar artery (PICA), allowing retrograde flow via the posterior communicating arteries to basilar artery. A 58-year-old woman who had subarachnoid hemorrhage was treated with endovascular occlusion of the right VA in acute stage after ballon occlusion test (BOT) of the right VA.

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In the distal posterior inferior cerebellar artery (PICA), saccular aneurysms originating at the first proximal segment, anterior medullary segment (AMS), are unusual but important due to the presence of critical perforators that branch off the PICA and supply the lower brainstem. Because the anatomy of the PICA varies, no standard treatment strategy has been agreed upon to date. We successfully treated 2 patients with open surgery.

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The combination of trigeminal neuralgia and ipsilateral hemifacial spasm, known as painful tic convulsif (PTC), is a relatively rare entity in neurovascular compression syndrome. A case of PTC attributable to different offending arteries is described, the mechanisms and characteristics of PTC are discussed, and a review of the literature is presented. This 80-year-old woman had a 10-year history of left trigeminal neuralgia and ipsilateral hemifacial spasm.

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The data for subarachnoid hemorrhage (SAH) from the Japanese Standard Stroke Registry Study (JSSRS) were analyzed to evaluate the incidence of SAH according to age, neurological grading and outcome, and outcome of surgical clipping, for comparison with the International Subarachnoid Aneurysm Trial (ISAT). From the ISSRS data, the peak incidence of SAH was the sixth decade in males and the eighth decade in females. The overall mortality was 22%, and good outcome, better than 2 on the modified Rankin Scale (mRS), at discharge was achieved in 58% of cases.

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We present the usefulness of Diffusion-weighted magnetic resonance images (DWI) in diagnosis and therapeutic strategy of deep cerebral venous thrombosis (VT). We report a 37-year-old man who suffered general convulsion and deep coma. Magnetic resonance imaging (MRI) showed high intensity in the right caudate nuclei and bilateral thalamus on T2-weighted images.

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We reported a case of subacute subarachnoid hemorrhage with watery clear cerebrospinal fluid. Emergent magnetic resonance image was useful not only for diagnosis by fluid attenuated inversion recovery image but also for evaluation of cerebral ischemia and vasospasm by magnetic resonance angiography, diffusion weighted image and perfusion weighted image. A 50-year-old man presented disturbance of consciousness and dysarthria.

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A 63-year-old male was admitted to our hospital, complaining of a scalp mass located at the frontoparietal area of his head. He noticed that it had been growing for 2 months. The mass was elastic hard and non-moving.

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An intradiploic epidermoid cyst of the skull in infancy is rare. We report a case of a 7-month-old girl with an intradiploic epidermoid cyst of the left parietal bone. The patient was admitted to the department of pediatrics in, our hospital in March, 2000, complaining of a lump in the scalp with a diameter of 1.

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