Browsing by Author "Gibo, Hirohiko (7003507969)"

The aim of this study was to examine the morphology and the immunohistochemical features of displaced ganglion cells in the trigeminal nerve root (TNR). Forty human TNRs of 20 persons, obtained during routine autopsy in accordance with the Declaration of Helsinki, were examined following Klüver-Barrera and azan trichrome histological staining, and immunohistochemical reactions against certain neuronal markers, neuropeptides and neurotransmitters. A total number of 61 displaced neurons were investigated, which were present in 80% of individuals studied. Displaced neurons were found in 55.0% of the TNRs, either in the sensory portion (22.5%), motor portion (22.5%) or both (10.0%). Neuronal diameter varied from 12.5 × 25.0 to 45.0 × 63.7 (mean 27.6 × 41.6) μm, and in area between 245 and 2,065 (mean 927) μm2. Each neuron was surrounded by 2-17 elongated satellite cells per slice. The immune reaction was positive in all the neurons studied for neuron-specific enolase, protein gene product 9.5, neurofilament protein and synaptophysin, and in some neurons for calcitonin gene-related peptide (CGRP; 24.4%), cholecystokinin (CCK; 13.3%), somatostatin (SST; 17.8%), substance P (SP; 15.6%), vasoactive intestinal polypeptide (4.4%), neuropeptide Y (8.9%), and serotonin (11.1%). The immune reactions were most frequent against the CGRP, SP, CCK and SST. We concluded that displaced neurons in the TNR morphologically and immunohistochemically resembled the sensory neurons in the trigeminal ganglion. Copyright © 2009 S. Karger AG, Basel.

OBJECTIVE: Intraventricular surgery requires a detailed knowledge of the microanatomy of the choroid plexus vasculature. METHODS: Twenty choroid plexuses were microdissected, and two additional plexuses were prepared for microscopic examination. RESULTS: The choroid plexus was perfused primarily by the anterior choroidal artery (AChA) and the lateral posterior choroidal artery (LPChA). The AChA, which averaged 650 μm in diameter, most often (in 75% of cases) divided into the medial and lateral trunks, which averaged 450 μm in diameter. The medial trunk gave off the bush-like intrachoroidal branches, whereas the lateral trunk divided into the parallel arteries. The inferior LPChA was present in 50% of the hemispheres, both the inferior and superior LPChAs in 40%, and their common trunk in 10%. In 40%, the LPChA, which averaged 670 μm in diameter, divided into the terminal trunks, with a mean diameter of 490 μm. The anastomoses involving the trunks of the LPChA and other choroidal arteries averaged 310 μm in diameter. All primary intrachoroidal branches of the AChA and LPChA were divided into three groups. The parallel branches, which averaged from 220 to 230 μm in diameter, coursed along the lateral part of the choroid plexus. The tortuous glomus vessels, which averaged 310 μm in size, originated from the AChA (45%), the LPChA (15%), or both (40%). The bush-like vessels, with a mean diameter between 155 and 190 μm, ramified into smaller twigs, up to the intrachoroidal capillaries. CONCLUSION: The data obtained on the microanatomy of the intrachoroidal vasculature may have certain neurosurgical implications.

Background: Scarce information about the anatomy of the subependymal arteries (SEAs) is present in the scientific literature. Methods: Twenty cerebral hemispheres with injected arteries were microdissected, and the magnetic resonance imaging scans of 100 patients with lacunar infarcts were examined. Results: The SEAs were found to range in diameter from 40 to 490 μm (mean, 149 μm) and in number between 3 and 12 (average, 5.2). Of these, numbers from 1 to 3 originated from the anterior choroidal artery (AChA), between 1 and 10 from the lateral posterior choroidal artery (LPChA), 1 from the medial posterior choroidal artery (MPChA), and 1 from the internal carotid artery. The SEAs most often arose from the choroidal branches (90%) and less frequently from the thalamic (30%), caudate (35%), or thalamocaudate twigs (20%). The SEAs of the AChA supplied the walls of the temporal horn (100%), the occipital horn (85%), and the atrium (35%). Those of the LPChA perfused the walls of the occipital horn (15%), the atrium (65%), the body of the ventricle (100%), and partially the frontal horn. The SEAs of the MPChA partially nourished the body and the frontal horn (10%). The SEAs may also occasionally supply the caudate nucleus (20%) and the stria terminalis. The anastomoses involving the SEAs were absent. In spite of this, ischemia in the territory of a single SEA was noticed in only 1% of our patients. Conclusions: The SEAs are tiny vessels that supply the walls of the lateral ventricle, as well as the caudate nucleus and the stria terminalis occasionally. The obtained anatomic data can have important neurosurgical implications in intraventricular operations. © 2005 Elsevier Inc. All rights reserved.

BACKGROUND: There is limited data in the literature related to the microanatomic features of the perforating branches of the vertebral artery. METHODS: The 44 vertebral arteries and their branches were injected with india ink or a radiopaque substance and examined under the stereoscopic microscope. RESULTS: The perforating arteries were noted to range in number from 1 to 11 (mean, 6.5) and in diameter between 100 μm and 520 μm (average, 243 μm). They arose from the vertebral artery (VA) (54.54%), 8 from the right, the left or both VAs. The anterior spinal artery (ASA), which was singular (81.82%), duplicated (13.64%), or plexiform (4.55%), always gave rise to the perforators. The vascular roots of the ASA were the source of the perforators in 95.45% of the brains. The latter vessels arose from the anterolateral arteries in 50% of the cases. The anastomoses involving the perforators, which were present in 40.91% of the brains, varied in diameter between 100 μm and 350 μm (mean, 169 μm). The perforating vessels gave rise to the side branches in 95.45% of the brains that varied in diameter from 100 μm to 300 μm (average, 161 μm). The perforators usually entered the foramen cecum and the anterior median sulcus, and then continued close and parallel to the raphe of the medulla. The perforators can be compressed by a VA aneurysm, which was found in one among the 71 examined patients with cerebral aneurysms. CONCLUSIONS: The obtained data give additional information about the vascular anatomy of the pontomedullary region. © 2004 Elsevier Inc. All rights reserved.

BACKGROUND: While the characteristics of the vasculature of the second (intracanalicular) segment of the hypoglossal nerve are well known, the vascularization of the first (cisternal) segment of this nerve has not been examined so far. Many pathologic processes and malformations can be located in the premedullary cistern, which may affect the vasculature of the cisternal segment. Consequently, we decided to examine the blood supply of the cisternal segment. METHODS: The anatomic features of the cisternal segment and its vasculature were examined in 15 hypoglossal nerves after injection of india ink and gelatin into the vertebrobasilar arterial system. RESULTS: The cisternal segment was noted to consist of 3-15 long roots, which usually formed two trunks of the hypoglossal nerve. The roots of each nerve received blood from the anterolateral and the lateral medullary arteries, which ranged from 3 to 5 in number and between 100 μm and 500 μm in caliber. These arteries may arise from the perforating branches or the pontomedullary branch of the basilar artery; the vertebral artery or its perforators; the anterior spinal artery or its vascular roots; the posterior spinal artery; and the posterior inferior cerebellar artery. The main hypoglossal arteries, which ranged in diameter from 20 μm to 80 μm, always coursed along the dorsal surface of the roots of the hypoglossal nerve. CONCLUSIONS: The cisternal segment of the hypoglossal nerve was always vascularized by several vessels, which mainly originated from the vertebral artery and its branches. This observation was discussed from the neurosurgical point of view.

THE VASCULATURE OF the 29 roots of the trigeminal nerve was examined after india ink and gelatin had been injected into the vertebrobasilar arterial system. The trigeminal arteries were most often noted to arise from the superolateral pontine branch of the basilar artery (89.66%), and from the peduncular cerebellar branch of the anterior inferior cerebellar artery (75.86%). The trigeminocerebellar artery supplied two roots (6.89%) of the trigeminal nerves. The number of trigeminal arteries ranged from two to six, and their diameters ranged from 100 to 510 μm. Anastomoses among them were seen in 37.93% of the cases. The arteries formed the vascular rings around 58.61% of the roots. The motor portion of the trigeminal nerve most often received blood from the superolateral pontine artery (79.31%). The same artery most commonly supplied the rostral part of the sensory portion, which corresponded to the ophthalmic division of the trigeminal nerve. The superolateral artery, together with the inferolateral pontine artery and the peduncular cerebellar branch of the anterior inferior cerebellar artery, irrigated the middle part of the sensory portion, which corresponded to the maxillary division. The caudal part of that portion, which corresponded to the mandibular division, was commonly perfused by the peduncular cerebellar branch of the anterior inferior cerebellar artery. In this article, we discuss the possible clinical significance of the anatomic data observed. © by the Congress of Neurological Surgeons.

The 50 premamillary arteries (PremA), arising from 39 posterior communicating arteries (PCoA), were examined in injected human brains. The PremA, which commonly was single (71.8%) and less frequently double (28.2%), more often arose from the PCoA (97.4%) than from the posterior cerebralartery (PCA) (2.6%). The PremA ranged between 280 and 780 μm in diameter. It gave off side branches to the hypothalamus (23.1%), optic tract (10.2%), mamillary body (17.9%) and the crus cerebri (35.9%). The anastomoses involving the extracerebral segment of the PremA were present in 35.9% of the cases. They varied in caliber from 50 to 230 μm. The intracerebral segment of the PremA ranged from 280 to 490 μm in diameter. Our study gives a precise anatomic basis for safer operations on the aneurysms of the posterior communicating artery and adjacent vessels. © 2001 Harcourt Publishers Ltd.

The 50 premamillary arteries (PremA), arising from 39 posterior communicating arteries (PCoA), were examined in injected human brains. The PremA, which commonly was single (71.8%) and less frequently double (28.2%), more often arose from the PCoA (97.4%) than from the posterior cerebralartery (PCA) (2.6%). The PremA ranged between 280 and 780 μm in diameter. It gave off side branches to the hypothalamus (23.1%), optic tract (10.2%), mamillary body (17.9%) and the crus cerebri (35.9%). The anastomoses involving the extracerebral segment of the PremA were present in 35.9% of the cases. They varied in caliber from 50 to 230 μm. The intracerebral segment of the PremA ranged from 280 to 490 μm in diameter. Our study gives a precise anatomic basis for safer operations on the aneurysms of the posterior communicating artery and adjacent vessels. © 2001 Harcourt Publishers Ltd.

TWENTY-EIGHT ABDUCENT NERVES were examined after injecting india ink and gelatin into the vertebrobasilar arterial system. All the abducent nerves were found to be crossed and/or penetrated by the surrounding vessels. The ventral surface of the nerves was crossed by the anterior inferior cerebellar artery (AICA) (75.0%), the posterior inferior cerebellar artery (17.85%), the common trunk of the AICA and posterior inferior cerebellar artery (7.14%), the internal auditory artery (14.28%), the anterolateral artery (46.43%), the pontomedullary artery (92.86%), and the corresponding veins (46.43%). The dorsal surface of the cisternal segment was crossed by the AICA (35.71%), the inferolateral pontine artery (10.71%), the anterolateral artery (82.14%), and the certain veins (46.43%). Sixty-four percent of the cisternal segments were penetrated by one or more of the following vessels: the AICA (25.0%), the anterolateral artery (17.86%), the pontomedullary artery (3.57%), and/or by the corresponding veins (42.86%). The majority of the cisternal segments of the abducent nerves were supplied by the anterolateral arteries (85.71%), and only some of them by the AICA (14.29%) or the pontomedullary artery (7.14%). The authors discuss the possible clinical significance of the anatomical data. © by the Congress of Neurological Surgeons.

WE EXAMINED IN detail the cisternal segments of 15 trochlear nerves in brain stems injected with India ink and fixed in formalin. The nerves were found to emerge as singular trunks (33.3%), singular trunks with accessory rootlets (13.3%), or two or three roots with (26.7%) or without accessory rootlets (26.7%). The nerves were in close relationship or in contact with the superior cerebellar artery, that is, with the main trunk of the superior cerebellar artery, its medial and lateral terminal stems, the accessory superior cerebellar artery, and the vermian, paravermian, collicular, and lateral hemispheric arteries as well as their small branches. Some of these vessels were connected by anastomoses in 86.7% of the cases. The anastomotic channels varied from 40 to 530 pm in diameter. The cisternal segment of each trochlear nerve was usually supplied by a single long artery, which most often arose from the vermian artery (26.7%) or the collicular artery (26.7%). The feeding vessel ranged from 30 to 80 μm in caliber. We discuss the possible clinical significance of the anatomic data observed in the present study.

BACKGROUND: The available information about certain microanatomic features of the AChA perforators is incomplete. Precise knowledge of these vessels is necessary to understand the consequences of their occlusion and to safely operate in their region. METHODS: The AChA perforators were microdissected and examined under the stereoscopic microscope in 10 vascular casts and in 20 hemispheres injected with india ink or radiopaque substance. RESULTS: The perforating branches ranged in number from 2 to 9 (mean, 4.6) and in diameter between 90 μm and 600 μm (mean, 317 μm). The most proximal perforator arose 3.2 mm on average caudal to the AChA origin. The most distal (capsulothalamic) perforator varied in size from 200 μm to 610 μm (mean, 431 μm). One or more of the perforators always originated from the AChA (100%), but some of them also from the uncal (33.3%) or parahippocampal branch (10%) of the AChA, either as individual vessels only (70%) or from common trunks (30%). The perforators gave off the peduncular (20%), optic (23.3%), or uncal side branches (26.7%). CONCLUSIONS: Our findings concerning the origin, position, number, size, branching, penetration site, and relationships of the AChA perforators gave the anatomic basis for safe operations in patients with AChA aneurysms or mediobasal limbic epilepsy.

THE PERFORATING BRANCHES of the basilar artery were examined in 14 brain stems injected with india ink or methylmethacrylate. Three groups of the perforators were distinguished: the caudal, the middle, and the rostral. The caudal perforators varied in number from two to five and in diameter from 80 to 600 μm. In addition to their terminal branches, which entered the foramen cecum, the perforators occasionally branched off the pontomedullary artery, the pyramidal vessels, and the hypoglossal branches. The middle perforators arose either separately from the basilar artery or along with the basilar artery collateral branches. They ranged in number from five to nine and in diameter from 210 to 940 μm. The perforators gave rise to the pontomedullary artery (8.3%), the long pontine arteries (25.0%), and the anterolateral vessels (100%). The rostral perforators originated from the terminal part of the basilar artery (91.6%), as well as from the superior cerebellar artery (91.6%) and the posterolateral artery (16.6%). They varied in number from one to five and in diameter from 190 to 800 μm. The anastomoses among various perforating vessels were noted in 41.6 to 66.6% of the cases. The authors discussed the possible clinical significance of the anatomical data observed in this study. © by the Congress of Neurological Surgeons.

OBJECTIVE: Despite detailed studies of the perforating arteries, their relationships with the leptomeningeal arteries are almost unknown. These relationships can be of great significance during neurosurgical operations. METHODS: The arteries of the hemispheres, which ranged in number from 17 to 36, were injected with india ink or methylmethacrylate. RESULTS: The perforating vessels were noted to arise from the following leptomeningeal arteries: the subcallosal branch of the anterior communicating artery (26.6%); the median artery of the corpus callosum (6.6%); the medial orbitofrontal (6.6%) and the olfactory branch (3.3%) of the anterior cerebral artery; the accessory middle cerebral artery (3.3%); the frontal and temporal branches of the middle cerebral artery (66.6%); the temporal branches of the internal carotid and the anterior choroidal arteries (25% each); the peduncular branch of the posterior communicating artery (4.8%); the peduncular, collicular and medial posterior choroidal branches of the posterior cerebral artery (40%); the cerebellar branches (100%); the long pontine branches (20-26.6%); the anterolateral branches (33.3%) of the basilar artery; and the anterolateral or the lateral medullary branches (35.3%) of the vertebral artery. From 19.4 to 100% of some leptomeningeal vessels originated in the large perforating arteries. CONCLUSION: From 4.8 to 100% of certain groups of the perforating vessels originated in the leptomeningeal arteries. Occlusion of a leptomeningeal artery that gives rise to the perforating vessel(s) may lead to superficial and deep infarcts in the same patient.

Objective - To examine the possible pathological changes of the trigeminal vasculature in patients with neuralgia. Background - Such a study has never been performed before. The alterations of the trigeminal vessels could have important pathophysiological implications in the trigeminal neuralgia pathogenesis. Methods - The biopsy specimens for the electronmicroscopic (EM) and immunohistochemical examination were taken during a partial rhizotomy in 6 patients with trigeminal neuralgia and in 2 persons with trigeminal neuropathy. In addition, the 32 normal trigeminal nerves were used as the control specimens. Results - The vascular pathological alterations were noticed in 3 out of 6 neuralgia patients. The EM study revealed signs of apoptosis or degeneration, respectively, of some endothelial and smooth muscle cells in the wall of the trigeminal arterioles. The immune reactions against CD31, CD34, and α-smooth muscle actin in these cells were weaker than in the control specimens, but stronger against factor VIII. In addition, the arteriolar basement membranes, which were thickened, showed an intense laminin, fibronectin, and collagen IV immunoreactivity. Similarly, some endothelial cells and pericytes of the intratrigeminal capillaries also showed signs of apoptosis or degeneration, respectively. Their basement membrane was very thick and showed an intense immune reaction against laminin, fibronectin, and collagen IV. Conclusion - The observed pathological changes of the trigeminal vasculature could be the primary factor, while demyelination of the trigeminal nerve fibers could be the secondary process in some patients with neuralgia. © 2007 the Authors.

Objective - To examine the possible pathological changes of the trigeminal vasculature in patients with neuralgia. Background - Such a study has never been performed before. The alterations of the trigeminal vessels could have important pathophysiological implications in the trigeminal neuralgia pathogenesis. Methods - The biopsy specimens for the electronmicroscopic (EM) and immunohistochemical examination were taken during a partial rhizotomy in 6 patients with trigeminal neuralgia and in 2 persons with trigeminal neuropathy. In addition, the 32 normal trigeminal nerves were used as the control specimens. Results - The vascular pathological alterations were noticed in 3 out of 6 neuralgia patients. The EM study revealed signs of apoptosis or degeneration, respectively, of some endothelial and smooth muscle cells in the wall of the trigeminal arterioles. The immune reactions against CD31, CD34, and α-smooth muscle actin in these cells were weaker than in the control specimens, but stronger against factor VIII. In addition, the arteriolar basement membranes, which were thickened, showed an intense laminin, fibronectin, and collagen IV immunoreactivity. Similarly, some endothelial cells and pericytes of the intratrigeminal capillaries also showed signs of apoptosis or degeneration, respectively. Their basement membrane was very thick and showed an intense immune reaction against laminin, fibronectin, and collagen IV. Conclusion - The observed pathological changes of the trigeminal vasculature could be the primary factor, while demyelination of the trigeminal nerve fibers could be the secondary process in some patients with neuralgia. © 2007 the Authors.

The trigeminocerebellar artery was found on the left side in one of 22 brainstems, with the vasculature injected with India ink or methylmethacrylate. The trigeminocerebellar artery, which measured 910 μm in diameter, arose from the basilar artery. The artery was divided into the pontine, trigeminal, cerebellopontine, and cerebellar segments. The artery supplied the anterolateral and lateral part of the pons, the trigeminal nerve root, the middle cerebellar peduncle, and most of the petrosal surface of the cerebellar hemisphere. Although relatively rare, the trigeminocerebellar artery may cause trigeminal neuralgia. Occlusion of this artery would cause a syndrome similar to the lateral midpontine syndrome. The trigeminocerebellar artery could be misinterpreted on angiograms as the anterior inferior cerebellar artery with a high origin from the basilar artery.

Objective: Detailed ultrastructural and immunohistochemical examination of the trigeminal axons surrounded by the peripheral type of the myelin could add new information about the extent of the trigeminal nerve lesion in neuralgia. Patients, materials and methods: The examination comprised, firstly, the 10 trigeminal nerve roots (TNRs) in which the neurovascular contact was found in 20% of the cases, and the 2 additional control TNRs. Secondly, the biopsy specimens were taken from 6 patients with trigeminal neuralgia and 2 patients with trigeminal neuropathy following a partial TNR rhizotomy. The specimens were examined under the electron microscope (EM) and/or using the immunohistochemical (IHC) methods. Results: In addition to the central zone of demyelination, the EM examination of the TNR also revealed alterations of the peripheral myelin, i.e. deformation, thickening, demyelination and remyelination, as well as changes of the peripheral axons, that is, atrophy or hypertrophy, neurofilaments increase, loss of the myelin and sprouting occasionally. Some Schwann cells were also damaged. The IHC examination usually showed a moderate immune reaction against neuron-specific enolase (NSE) and protein gene product 9.5 (PGP9.5), but sporadically weaker reaction against the S-100 protein, synaptophysin (SY), neurofilament protein (NFP) and glial fibrillary acidic protein (GFAP). The substance P (SP) and calcitonin gene-related peptide (CGRP) immunoreactivity was weak at some sites, but strong at some other places. Conclusions: The pathological changes affect not only the central nerve fibers of the TNR, but also some of the peripheral axons, their myelin sheath and Schwann cells. These are signs of the retrograde ultrastructural and biochemical alterations, which could participate in the pathophysiological mechanism underlying the trigeminal neuralgia. © 2009 Elsevier B.V. All rights reserved.