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Yukimasa Yasumoto - One of the best experts on this subject based on the ideXlab platform.
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Diploic Veins of the cranial base: an anatomical study using magnetic resonance imaging
Surgical and Radiologic Anatomy, 2019Co-Authors: Satoshi Tsutsumi, Hisato Ishii, Yukimasa YasumotoAbstract:Purpose The anatomy and distribution of the Diploic Veins (DVs) of the cranial base have not been fully documented. The aim of this study was to characterize these Veins using contrast magnetic resonance imaging (MRI). Methods In total, 95 patients underwent thin-sliced, contrast MRI. Coronal and sagittal images were used for the analysis. The cranial base was divided into the anterior, middle, and posterior bases. Then, each base was further subdivided into three equal parts in the anteroposterior and lateromedial directions. The anteroposterior parts were evaluated on coronal images, while the lateromedial parts were evaluated on sagittal images. Results The DVs were identified over the entire cranial base. However, they were more frequent in the posterior-third of the lateral-third region of the anterior, middle-third of the lateral and middle-third regions of the middle, and middle-third region of the posterior cranial base, and sparse in the posterior and medial-third regions of the middle cranial base. The DVs showed marked morphological variability. For instance, the DVs of the pterional area were generally well defined, as pivotal channels connecting the lateral parts of the anterior and middle cranial base, but were highly varied in appearance. Conclusions The DVs of the cranial base are distinct structures characterized by morphological variability and topographical predilection. Contrast MRI is useful for delineating these Veins.
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Diploic Veins of the cranial base an anatomical study using magnetic resonance imaging
Surgical and Radiologic Anatomy, 2019Co-Authors: Satoshi Tsutsumi, Hisato Ishii, Yukimasa YasumotoAbstract:Purpose The anatomy and distribution of the Diploic Veins (DVs) of the cranial base have not been fully documented. The aim of this study was to characterize these Veins using contrast magnetic resonance imaging (MRI).
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Visualization of the supraorbital notch/foramen using magnetic resonance imaging.
Journal of Clinical Neuroscience, 2019Co-Authors: Satoshi Tsutsumi, Hisato Ishii, Yukimasa YasumotoAbstract:Abstract The supraorbital notch/foramen involving the segment of the supraorbital nerve (SON) and the supraorbital artery (SOA) has little been explored with magnetic resonance imaging (MRI). Therefore, we explored these structures using MRI. A total of 90 patients underwent thin-sliced contrast MRI. In addition, eight sides of the orbits were dissected in four cadaveric heads. Cadaver dissections showed that the SOA coursed consistently beneath and in close proximity to the SON and reached the supraorbital notch/foramen. On axial MRI images, the supraorbital notch/foramen was identified in 98% on the right side and in 99% on the left. The distance from the midline to the midpoint of the supraorbital notch/foramen and depth from the skin surface to the supraorbital foramen/exit were measured. The median distance was 22.6 ± 3.08 mm on the right side and 22.8 ± 3.07 mm on the left, whereas the depth was 7.7 ± 1.39 mm on the right and 7.7 ± 1.43 mm on the left. Eighty percent of the sagittal images showed well-developed Diploic Veins in the supraorbital rim. Of these, 8.3% had anastomotic channels with the subcutaneous Veins through the anterior wall of the supraorbital rim, 11.8% through the inferior wall, and 9% through the SOF. The SON and SOA segments passing through the supraorbital exit can be reliably located using contrast MRI. The supraorbital rim may function as the intracranial to extracranial anastomotic channel.
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Pile driving into the skull and suspending the bridging Veins? An undescribed role of arachnoid granulations
Surgical and Radiologic Anatomy, 2017Co-Authors: Satoshi Tsutsumi, Yukimasa YasumotoAbstract:Purpose Arachnoid granulations (AGs) occasionally appear to protrude into the calvarial convexity, lying close to the bridging Veins (BVs). This study aims to characterize such AGs and BVs using magnetic resonance imaging (MRI). Methods Ninety-five patients were enrolled in this study. Initially, stepwise frontal craniotomy was performed in an injected cadaver head. Next, examinations with contrast MRI were performed involving the whole cranial vault. Results In cadaveric dissection, the AGs located in the parasagittal regions appeared as outward protrusions through the dura mater and in contact with the Diploic Veins. Forming tent-shaped sleeves, these AGs and the continuous arachnoid membranes suspended the BVs coursing just below. A total of 237 AGs were identified on contrast MRI that protruded into the skull, lying close to the BVs. Among them, 78 % were located in parasagittal regions as AG–BV pairs. These pairs were most frequently found in the middle third of the calvarial hemisphere, followed by the anterior and posterior thirds. In 34 %, the BV segments were lodged in the AGs. Conclusions Some AGs located in the parasagittal regions and cerebral convexity pass through the dura mater and pile drive into the skull, which contribute to forming hanging-type arachnoid sleeves suspending the BVs. These structures may underpin the predisposition of BVs to injury following mechanical impacts.
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cerebrospinal fluid drainage through the Diploic and spinal epidural Veins
Journal of Anatomy, 2015Co-Authors: Satoshi Tsutsumi, Ikuko Ogino, Masakazu Miyajima, Hajime Arai, Yukimasa YasumotoAbstract:: The aim of this study was to quantitatively evaluate the function of the cranial Diploic and spinal epidural Veins as cerebrospinal fluid (CSF) drainage pathways by measuring lipocalin-type prostaglandin D synthase (PGDS) and cystatin C (CysC) dissolved in the blood of these Veins. This was a prospective study involving 51 consecutive patients, 31 males and 20 females, who underwent 41 cranial and 10 spinal surgeries. Intraoperatively, peripheral venous blood and Diploic venous blood, or peripheral venous blood and spinal epidural venous blood samples were simultaneously collected and immediately centrifuged. For all samples, dissolved albumin (for reference), PGDS and CysC were measured using an enzyme-linked immunosorbent assay. The Diploic vein/peripheral vein ratios in five cranial locations and epidural vein/peripheral vein ratios were calculated and statistically evaluated for the three biomarkers. For PGDS, the Diploic vein/peripheral vein ratio was significantly increased in the frontal (P = 0.011), temporal (P = 0.028), parietal (P = 0.046) and skull base (P = 0.039), while it did not reach statistical significance for CysC. For patients older than 45 years, the Diploic vein/peripheral vein ratio for PGDS was significantly decreased in the frontal region (P = 0.028), and the epidural vein/peripheral vein ratio for CysC was significantly decreased (P = 0.014). These results show that the Diploic Veins constitute CSF drainage pathways with heterogeneous functional intensity at different cranial locations. Compared with the Diploic Veins, spinal epidural Veins seem to drain less CSF. The cranial Diploic and spinal epidural Veins may jointly function as an alternative, age-related trans-dural CSF drainage system.
Satoshi Tsutsumi - One of the best experts on this subject based on the ideXlab platform.
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Diploic Veins of the cranial base: an anatomical study using magnetic resonance imaging
Surgical and Radiologic Anatomy, 2019Co-Authors: Satoshi Tsutsumi, Hisato Ishii, Yukimasa YasumotoAbstract:Purpose The anatomy and distribution of the Diploic Veins (DVs) of the cranial base have not been fully documented. The aim of this study was to characterize these Veins using contrast magnetic resonance imaging (MRI). Methods In total, 95 patients underwent thin-sliced, contrast MRI. Coronal and sagittal images were used for the analysis. The cranial base was divided into the anterior, middle, and posterior bases. Then, each base was further subdivided into three equal parts in the anteroposterior and lateromedial directions. The anteroposterior parts were evaluated on coronal images, while the lateromedial parts were evaluated on sagittal images. Results The DVs were identified over the entire cranial base. However, they were more frequent in the posterior-third of the lateral-third region of the anterior, middle-third of the lateral and middle-third regions of the middle, and middle-third region of the posterior cranial base, and sparse in the posterior and medial-third regions of the middle cranial base. The DVs showed marked morphological variability. For instance, the DVs of the pterional area were generally well defined, as pivotal channels connecting the lateral parts of the anterior and middle cranial base, but were highly varied in appearance. Conclusions The DVs of the cranial base are distinct structures characterized by morphological variability and topographical predilection. Contrast MRI is useful for delineating these Veins.
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Diploic Veins of the cranial base an anatomical study using magnetic resonance imaging
Surgical and Radiologic Anatomy, 2019Co-Authors: Satoshi Tsutsumi, Hisato Ishii, Yukimasa YasumotoAbstract:Purpose The anatomy and distribution of the Diploic Veins (DVs) of the cranial base have not been fully documented. The aim of this study was to characterize these Veins using contrast magnetic resonance imaging (MRI).
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Visualization of the supraorbital notch/foramen using magnetic resonance imaging.
Journal of Clinical Neuroscience, 2019Co-Authors: Satoshi Tsutsumi, Hisato Ishii, Yukimasa YasumotoAbstract:Abstract The supraorbital notch/foramen involving the segment of the supraorbital nerve (SON) and the supraorbital artery (SOA) has little been explored with magnetic resonance imaging (MRI). Therefore, we explored these structures using MRI. A total of 90 patients underwent thin-sliced contrast MRI. In addition, eight sides of the orbits were dissected in four cadaveric heads. Cadaver dissections showed that the SOA coursed consistently beneath and in close proximity to the SON and reached the supraorbital notch/foramen. On axial MRI images, the supraorbital notch/foramen was identified in 98% on the right side and in 99% on the left. The distance from the midline to the midpoint of the supraorbital notch/foramen and depth from the skin surface to the supraorbital foramen/exit were measured. The median distance was 22.6 ± 3.08 mm on the right side and 22.8 ± 3.07 mm on the left, whereas the depth was 7.7 ± 1.39 mm on the right and 7.7 ± 1.43 mm on the left. Eighty percent of the sagittal images showed well-developed Diploic Veins in the supraorbital rim. Of these, 8.3% had anastomotic channels with the subcutaneous Veins through the anterior wall of the supraorbital rim, 11.8% through the inferior wall, and 9% through the SOF. The SON and SOA segments passing through the supraorbital exit can be reliably located using contrast MRI. The supraorbital rim may function as the intracranial to extracranial anastomotic channel.
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Pile driving into the skull and suspending the bridging Veins? An undescribed role of arachnoid granulations
Surgical and Radiologic Anatomy, 2017Co-Authors: Satoshi Tsutsumi, Yukimasa YasumotoAbstract:Purpose Arachnoid granulations (AGs) occasionally appear to protrude into the calvarial convexity, lying close to the bridging Veins (BVs). This study aims to characterize such AGs and BVs using magnetic resonance imaging (MRI). Methods Ninety-five patients were enrolled in this study. Initially, stepwise frontal craniotomy was performed in an injected cadaver head. Next, examinations with contrast MRI were performed involving the whole cranial vault. Results In cadaveric dissection, the AGs located in the parasagittal regions appeared as outward protrusions through the dura mater and in contact with the Diploic Veins. Forming tent-shaped sleeves, these AGs and the continuous arachnoid membranes suspended the BVs coursing just below. A total of 237 AGs were identified on contrast MRI that protruded into the skull, lying close to the BVs. Among them, 78 % were located in parasagittal regions as AG–BV pairs. These pairs were most frequently found in the middle third of the calvarial hemisphere, followed by the anterior and posterior thirds. In 34 %, the BV segments were lodged in the AGs. Conclusions Some AGs located in the parasagittal regions and cerebral convexity pass through the dura mater and pile drive into the skull, which contribute to forming hanging-type arachnoid sleeves suspending the BVs. These structures may underpin the predisposition of BVs to injury following mechanical impacts.
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cerebrospinal fluid drainage through the Diploic and spinal epidural Veins
Journal of Anatomy, 2015Co-Authors: Satoshi Tsutsumi, Ikuko Ogino, Masakazu Miyajima, Hajime Arai, Yukimasa YasumotoAbstract:: The aim of this study was to quantitatively evaluate the function of the cranial Diploic and spinal epidural Veins as cerebrospinal fluid (CSF) drainage pathways by measuring lipocalin-type prostaglandin D synthase (PGDS) and cystatin C (CysC) dissolved in the blood of these Veins. This was a prospective study involving 51 consecutive patients, 31 males and 20 females, who underwent 41 cranial and 10 spinal surgeries. Intraoperatively, peripheral venous blood and Diploic venous blood, or peripheral venous blood and spinal epidural venous blood samples were simultaneously collected and immediately centrifuged. For all samples, dissolved albumin (for reference), PGDS and CysC were measured using an enzyme-linked immunosorbent assay. The Diploic vein/peripheral vein ratios in five cranial locations and epidural vein/peripheral vein ratios were calculated and statistically evaluated for the three biomarkers. For PGDS, the Diploic vein/peripheral vein ratio was significantly increased in the frontal (P = 0.011), temporal (P = 0.028), parietal (P = 0.046) and skull base (P = 0.039), while it did not reach statistical significance for CysC. For patients older than 45 years, the Diploic vein/peripheral vein ratio for PGDS was significantly decreased in the frontal region (P = 0.028), and the epidural vein/peripheral vein ratio for CysC was significantly decreased (P = 0.014). These results show that the Diploic Veins constitute CSF drainage pathways with heterogeneous functional intensity at different cranial locations. Compared with the Diploic Veins, spinal epidural Veins seem to drain less CSF. The cranial Diploic and spinal epidural Veins may jointly function as an alternative, age-related trans-dural CSF drainage system.
Makoto Taniguchi - One of the best experts on this subject based on the ideXlab platform.
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A rare case of Diploic venous anomaly: asymptomatic venous sac expanding in the diploe.
SpringerPlus, 2016Co-Authors: Hirokazu Iwamuro, Shunsuke Ikeda, Makoto TaniguchiAbstract:Background Vascular anomalies accompanied with the Diploic Veins are rare. Among them, sinus pericranii, which is characterized by abnormal connections between intra- and extracranial venous systems, is relatively common. Besides sinus pericranii, a few cases of subepicranial varix with connections to Diploic Veins have been reported, but these varices had no connections to intracranial venous sinuses. Herein, we present a rare case of an expanding venous sac in the diploe which communicated with the intracranial sinus but not with the extracranial venous systems.
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A rare case of Diploic venous anomaly: asymptomatic venous sac expanding in the diploe
SpringerPlus, 2016Co-Authors: Hirokazu Iwamuro, Shunsuke Ikeda, Makoto TaniguchiAbstract:Background Vascular anomalies accompanied with the Diploic Veins are rare. Among them, sinus pericranii, which is characterized by abnormal connections between intra- and extracranial venous systems, is relatively common. Besides sinus pericranii, a few cases of subepicranial varix with connections to Diploic Veins have been reported, but these varices had no connections to intracranial venous sinuses. Herein, we present a rare case of an expanding venous sac in the diploe which communicated with the intracranial sinus but not with the extracranial venous systems. Case presentation An adult woman presented to us with a minor transient headache. Although no abnormal appearances were found on her scalp, imaging studies showed a club-shaped venous sac in the left parietal diploe that communicated with the superior sagittal sinus and Diploic Veins on the medial and lateral sides, respectively. It was revealed that the lesion had expanded as compared with a previous computed tomography image. Surgery was performed to intercept venous supply from the Diploic Veins, and the lesion was filled with thrombi. In a follow-up of 15 months, there was no recurrence of abnormal venous flow. Histological examination showed the endothelial lining in the membranous wall of the sac, which is typically observed in sinus pericranii. However, no communication with the pericranial Veins of the scalp was identified on the imaging studies and intraoperative observation. Accordingly, it was diagnosed as another entity “intraDiploic varix”. Conclusions The abnormal connection between the intracranial and the Diploic venous systems via the large venous sac was surgically treated. It was pathologically similar to sinus pericranii, but anatomically considered to be another form of venous anomaly. In cases of expanding lesions, surgical treatment is recommended.
Hirokazu Iwamuro - One of the best experts on this subject based on the ideXlab platform.
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A rare case of Diploic venous anomaly: asymptomatic venous sac expanding in the diploe.
SpringerPlus, 2016Co-Authors: Hirokazu Iwamuro, Shunsuke Ikeda, Makoto TaniguchiAbstract:Background Vascular anomalies accompanied with the Diploic Veins are rare. Among them, sinus pericranii, which is characterized by abnormal connections between intra- and extracranial venous systems, is relatively common. Besides sinus pericranii, a few cases of subepicranial varix with connections to Diploic Veins have been reported, but these varices had no connections to intracranial venous sinuses. Herein, we present a rare case of an expanding venous sac in the diploe which communicated with the intracranial sinus but not with the extracranial venous systems.
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A rare case of Diploic venous anomaly: asymptomatic venous sac expanding in the diploe
SpringerPlus, 2016Co-Authors: Hirokazu Iwamuro, Shunsuke Ikeda, Makoto TaniguchiAbstract:Background Vascular anomalies accompanied with the Diploic Veins are rare. Among them, sinus pericranii, which is characterized by abnormal connections between intra- and extracranial venous systems, is relatively common. Besides sinus pericranii, a few cases of subepicranial varix with connections to Diploic Veins have been reported, but these varices had no connections to intracranial venous sinuses. Herein, we present a rare case of an expanding venous sac in the diploe which communicated with the intracranial sinus but not with the extracranial venous systems. Case presentation An adult woman presented to us with a minor transient headache. Although no abnormal appearances were found on her scalp, imaging studies showed a club-shaped venous sac in the left parietal diploe that communicated with the superior sagittal sinus and Diploic Veins on the medial and lateral sides, respectively. It was revealed that the lesion had expanded as compared with a previous computed tomography image. Surgery was performed to intercept venous supply from the Diploic Veins, and the lesion was filled with thrombi. In a follow-up of 15 months, there was no recurrence of abnormal venous flow. Histological examination showed the endothelial lining in the membranous wall of the sac, which is typically observed in sinus pericranii. However, no communication with the pericranial Veins of the scalp was identified on the imaging studies and intraoperative observation. Accordingly, it was diagnosed as another entity “intraDiploic varix”. Conclusions The abnormal connection between the intracranial and the Diploic venous systems via the large venous sac was surgically treated. It was pathologically similar to sinus pericranii, but anatomically considered to be another form of venous anomaly. In cases of expanding lesions, surgical treatment is recommended.
Hideyuki Kuyama - One of the best experts on this subject based on the ideXlab platform.
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Experimental study of venous circulatory disturbance by dural sinus occlusion
Acta Neurochirurgica, 1993Co-Authors: M. Gotoh, Takashi Ohmoto, Hideyuki KuyamaAbstract:Using a newly devised model of dural sinus occlusion, we investigated the pathophysiology of venous haemorrhage as well as venous circulatory disturbance. The superior sagittal sinus (SSS) and Diploic Veins (DV) were occluded in 16 cats. Intracranial pressure (ICP), cerebral blood volume (CBV) and regional cerebral blood flow (rCBF) were measured for 12 hours after the occlusion. At the end of the experiment, cerebral water content was estimated. In another 8 cats additional occlusions of cortical Veins were carried out. In both groups, the blood-brain barrier permeability was evaluated with Evans blue or horseradish peroxidase.
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Experimental Study in Cerebral Venous Circulatory Disturbance: With Special Reference to Venous Hemorrhage
Recent Advances in Neurotraumatology, 1993Co-Authors: M. Gotoh, Takashi Ohmoto, Toru Fukuhara, T. Shirakawa, S. Nishino, Toshikazu Saijyo, Masamitsu Kawauchi, Hideyuki KuyamaAbstract:Using a new devised model of dural sinus occlusion, we investigated the pathophysiology including venous hemorrhage. Sixteen cats received, the occlusion of superior sagittal sinus(SSS) and Diploic Veins(DV). Intracranial pressure(ICP), cerebral blood volume(CB V) and regional cerebral blood flow(rCBF) were measured for 12 hours. At sacrifice, cerebral water content was determined. Other 8 cats received the additional occlusion of cortical Veins(CV). In both groups, the blood-brain barrier(BBB) permeability was evaluated with Evans blue. The SSS and DV occlusion produced a significant increase in ICP and CBV and a significant decrease in rCBF. Cerebral water content also increased significantly. However, neither extravasated Evans blue nor venous hemorrhage could be observed, when thrombus was defined within SSS. Contrarily, the additional CV occlusion produced hemorrhagic infarctions in 6 cats, where Evans blue dye extravasated. These data suggest that durai sinus occlusion led to an increase in CBV and cerebral water content resulting in intracranial hypertension, and decreased rCBF. The brain edema in this model seemed to be hydrostatic edema. The obstruction of CV might be essential in the development of hemorrhage in this model, and the BBB was disrupted in these areas.
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Experimental study of venous circulatory disturbance by dural sinus occlusion
Acta Neurochirurgica, 1993Co-Authors: M. Gotoh, Takashi Ohmoto, Hideyuki KuyamaAbstract:Using a newly devised model of dural sinus occlusion, we investigated the pathophysiology of venous haemorrhage as well as venous circulatory disturbance. The superior sagittal sinus (SSS) and Diploic Veins (DV) were occluded in 16 cats. Intracranial pressure (ICP), cerebral blood volume (CBV) and regional cerebral blood flow (rCBF) were measured for 12 hours after the occlusion. At the end of the experiment, cerebral water content was estimated. In another 8 cats additional occlusions of cortical Veins were carried out. In both groups, the blood-brain barrier permeability was evaluated with Evans blue or horseradish peroxidase. The SSS and DV occlusion produced a significant increase in ICP and CBV concomitant with a significant decrease in rCBF. Cerebral water content also increased significantly. However, there was no transition of Evans blue and horseradish peroxidase through the cerebral vessels, and no haemorrhages could be observed. In contrast, the additional occlusion of cortical Veins produced haemorrhagic infarctions with Evans blue extravasation in 6 out of the 8 cats. These data suggest that dural sinus occlusion may lead to an increase in CBV and cerebral water content resulting in intracranial hypertension and decreased rCBF. The brain oedema in this model seemed to be mainly hydrostatic oedema, and might also be contributed by cytotoxic oedema. The additional occlusion of cortical Veins might be essential in the development of haemorrhage in this model, and the blood-brain barrier was also disrupted in these areas.