Biomedical subjects

H Gibo

Publications and source records attributed to H Gibo.

At least 37 records · Page 2Linked to original sources

PubMed1995

Characteristics of pterional routes to basilar bifurcation aneurysm.

In an attempt to clarify the characteristics of the pterional routes to the basilar bifurcation aneurysm, 65 consecutive surgical cases were retrospectively analyzed concerning the size of the aneurysm, the height of the aneurysm neck, the length of the clip blades, and the direction of clip application. Clipping was performed through the pterional route in 59 cases consisting of 14 opticocarotid and 45 retrocarotid routes. A subtemporal approach was performed for six low-positioned aneurysms. The opticocarotid approach was undertaken because of the following situations: 1) laterally protruded and/or highly sclerotic internal carotid artery (n = 8); 2) long, redundant A1 segment (n = 3); 3) an associated aneurysm of the internal carotid artery obstructing the retrocarotid space (n = 2); and 4) a short and/or large posterior communicating artery obstructing the retrocarotid space (n = 1). The range in height of the aneurysm neck was narrower in the opticocarotid approach (1-10 mm) than in the retrocarotid approach (-7-15 mm). The direction of clip application on the axial plane was more anteriorly deviated in the opticocarotid approach (41.4 +/- 12.8 degrees from the glabella-inion line) than in the retrocarotid approach (58.8 +/- 11.1 degrees; P = 0.01). The retrocarotid route (n = 45) was further subdivided into the medial or lateral retrocarotid routes, depending on the medial or lateral side to the posterior communicating artery, respectively. The medial retrocarotid approach (n = 9) made it possible to reach relatively high-positioned aneurysms (7.0 +/- 3.9 mm) compared with the lateral retrocarotid approach (4.2 +/- 4.7 mm; n = 29).(ABSTRACT TRUNCATED AT 250 WORDS)

Basilar Artery↗

PubMed1995

The blood supply of the trigeminal nerve root, with special reference to the trigeminocerebellar artery.

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 microns. 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.

Adult↗

PubMed1994

The neurovascular relationships and the blood supply of the oculomotor nerve: the microsurgical anatomy of its cisternal segment.

The 27 oculomotor nerves were examined after injection of India ink or methylmethacrylate into the vertebral and the internal carotid arteries. The ventral surface of the cisternal segment of the nerve was noted to be in close relationship with the superior cerebellar artery (96.3%) and its pontine (37.0%), mesencephalic (25.9%) and perforating branches (81.5%); the posterolateral pontine artery (70.4%) and its branches; the anterolateral pontine branches (29.6%), and the perforating branches (85.2%) of the basilar artery; the mesencephalic perforating arteries (11.1%) and their peduncular branches (62.9%); the peduncular branches of the diencephalic perforators (11.1%) and the P1 segment (18.5%); and the accessory collicular artery (3.7%). The dorsal surface of the nerve was in close relationships to the P1 and P2A segments (100%) of the posterior cerebral artery and their peduncular branches (22.2%); the posterior communicating artery (100%); the collicular (100%) and the accessory collicular artery (33.3%), and their peduncular (51.8%) or the perforating branches (22.2%); the medial posterior choroidal artery (25.9%) and its branches (11.1%); and the mesencephalic and diencephalic perforating arteries (100%). Vascular penetration was noted in 51.8% of the third nerves. The most common penetrating vessel was the collicular artery (18.5%) and its branches (22.2%). The cisternal segment of the oculomotor nerve was most often supplied by the mesencephalic perforators (88.9%). The authors discuss the possible clinical significance of the obtained anatomic data.

Humans↗

PubMed1994

Vertebrobasilar junction fenestration associated with dissecting aneurysm of intracranial vertebral artery.

BACKGROUND: Vertebrobasilar junction fenestration is considered to be a subtype of fenestration of the proximal basilar artery, which has been described only in autopsy cases. The fenestration associated with a dissecting vertebral aneurysm is extremely rare. CASE DESCRIPTION: A 47-year-old man presented with subarachnoid hemorrhage. The four-vessel angiogram showed a fusiform dilatation with an intimal flap of the left vertebral artery distal to the origin of the posterior inferior cerebellar artery and a fenestration at the vertebrobasilar junction, in which a small limb of the fenestration arising from the distal portion of the left vertebral artery bridged the proximal basilar trunk, while another limb had a large diameter showing the same diameter as the basilar artery. The dissecting aneurysm was treated with body clipping by directly clipping the ruptured portion of the aneurysm via a suboccipital approach in an early operation 48 hours after the ictus. The patient had a good recovery and returned to his work. He is well at a 5-year follow-up. CONCLUSIONS: The relevant angiographic features of the vertebrobasilar junction fenestration and the surgical treatment of such associated aneurysms are discussed.

Aortic Dissection↗

PubMed1994

Huge uncal branch of the anterior choroidal artery.

A huge uncal branch of the anterior choroidal artery was found in one of 22 cerebral hemispheres. The uncal artery measured 0.7 mm in diameter. It gave off small branches to the uncus, as well as a large parahippocampal artery, the accessory anterior temporal artery, and the anterior hippocampal artery. This uncal artery supplied, in addition to the uncus, most of the ventromedial surface of the parahippocampal gyrus, part of its dorsal surface, the rostromedial portion of the lateral occipitotemporal gyrus, and the rostral part of the hippocampal formation. Such a huge uncal artery has implications for surgery in the uncohippocampal region.

Autopsy↗

PubMed1994

The neurovascular relationships and the blood supply of the abducent nerve: surgical anatomy of its cisternal segment.

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.

Abducens Nerve↗

PubMed1993

Preservation of cochlear nerve function in acoustic neurinoma surgery.

A total of 55 cases with unilateral acoustic neurinoma which were operated on by the lateral suboccipital approach was studied to elucidate factors which influence postoperative hearing acuity. We analyzed several factors: preoperative hearing level, tumour size, tumour consistency (cystic or solid), and anatomical location of the cochlear nerve. The size of the tumours ranged from 1.2 to 5.8 cm in diameter. Thirty of 55 cases (55%) preoperatively had remaining cochlear function. The smaller the size of tumour, the higher was the preoperative hearing level excepting those tumours with a diameter of 5 cm or greater, which had relatively good hearing and often contained large cysts. As to the consistency of the tumours, 41 were solid and 14 were cystic, where 19 (46%) and 11 (79%) cases had had preoperative hearing, respectively. Anatomical continuity of the cochlear nerve was maintained at surgery in 15 of 30 cases with preoperatively remaining hearing; cochlear function was preserved after surgery in 9 of the 15 cases. It was located counter-clockwise (caudally) to the facial nerve at an angle of 50 degrees on average when they were projected on the right side. The distance or interrelation between the two nerves had no bearing on postoperative hearing preservation. Postoperatively, hearing acuity was improved in 6 cases (20%) with a mean value of 5.6 dB, unchanged in 3 (10%), and deteriorated in 21 (70%) among the 30 cases with remaining preoperative-hearing. When the tumour was less than 2 cm or cystic, better hearing preservation was expected.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

The surgical anatomy of the perforating branches of the basilar artery.

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 microns. 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 microns. 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 microns. 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.

Basilar Artery↗

PubMed1993

Large dorsal internal carotid artery aneurysm--report of two cases.

Two patients with unusually large dorsal internal carotid artery aneurysms manifesting as subarachnoid hemorrhage are described. Surgery in both cases resulted in intraoperative rupture of the sac. The outcome was poor in the first patient and excellent in the second. The importance of wide exposure of the proximal and distal vasculature to the aneurysm, subpial dissection of the frontal and temporal lobes not to injure the fragile aneurysmal dome, and parallel clipping was emphasized for this rare type of aneurysm.

Adult↗

PubMed1993

A study of safe entry zones via the floor of the fourth ventricle for brain-stem lesions. Report of three cases.

Direct surgery for intra-axial lesions of the brain stem is considered a hazardous procedure, and morbidity of varying degrees cannot be avoided even with partial removal or biopsy. The main causes of morbidity relate to direct damage during removal of the lesion, selection of an entry route into the brain stem, and the direction of brain stem retraction. The authors examined the possibility of making a medullary incision and retracting the brain stem, taking into account the symptomatology and surgical anatomy, and found two safe entry zones into the brain stem through a suboccipital approach via the floor of the fourth ventricle. These safe entry zones are areas where important neural structures are less prominent. One is the "suprafacial triangle," which is bordered medially by the medial longitudinal fascicle, caudally by the facial nerve (which runs in the brain-stem parenchyma), and laterally by the cerebellar peduncle. The second is the "infrafacial triangle," which is bordered medially by the medial longitudinal fascicle, caudally by the striae medullares, and laterally by the facial nerve. In order to minimize the retraction-related damage to important brain-stem structures, the brain stem should be retracted either laterally or rostrally in the suprafacial triangle approach and only laterally in the infrafacial triangle approach. Three localized intra-axial brain-stem lesions were treated surgically via the safe entry zones using the suprafacial approach in two and the infrafacial approach in one. The cases are described and the approaches delineated. Both approaches are indicated for focal intra-axial lesions located unilaterally and dorsal to the medial lemniscus in the lower midbrain to the pons. Magnetic resonance imaging is useful in selecting these approaches, and intraoperative ultrasonography is helpful to confirm the exact location of a lesion before a medullary incision is made. These approaches can also be used as routes for aspiration of brain-stem hemorrhage as well as for tumor biopsy.

Adult↗

PubMed1993

[Arteries to the pituitary].

The arteries of the pituitary stalk and gland were described using our results as well as data obtained from the literature. There were three types of vessels to the pituitary from above: the superior hypophyseal artery originating from the internal carotid artery, the infundibular artery originating from the posterior communicating artery, and the prechiasmal artery from the ophthalmic artery. There were also three arteries from the cavernous carotid artery; the inferior hypophyseal artery, the capsular artery, and the artery of the inferior cavernous sinus. These arteries were anastomosed each other, making the rich vascular networks, called the "circuminfundibular anastomosis" around the pituitary stalk, and the "inferior hypophyseal arterial circle (or inferior capsular arterial rete)" in the base of the pituitary.

Carotid Artery, Internal↗

PubMed1992

Introduction of high definition television system to neurosurgical documentation.

The high definition television (HDTV) system is introduced to microneurosurgery. Five cases with intracranial lesions: three cerebral aneurysms (giant aneurysms of the anterior communicating artery and internal carotid artery, aneurysm of the basilar artery), one acoustic neurinoma and one skull base meningioma, were operated on under the microscope using the HDTV system. The surgical procedures of each case were relayed and recorded by the system. In two of the five cases, we used two sets of HDTV system to produce stereoscopic projection. The HDTV system provided us with images of superior quality with a distinctly greater resolution than ordinary video systems.

Adult↗

PubMed1991

Development of the operating computerized tomographic scanner system for neurosurgery.

A computerized tomographic (CT) scanner system for intraoperative imaging is presented. The system consists of the following: 1) CT scanner with a mobile gantry, 2) digitally controlled operating table with central processing unit (CPU) and encoder unit; the table can be controlled by the scanner computer as accurately as the scanner bed, and 3) exclusively designed head fixation devices. It allows us to scan the patient on the operating table in the operating room pre-operatively, intra-operatively and immediately after surgery.

Computer Systems↗

PubMed1991

The thalamogeniculate perforators of the posterior cerebral artery: the microsurgical anatomy.

The thalamogeniculate (TG) arteries of 30 forebrain hemispheres were examined. These vessels varied from 2 to 12 in number (mean, 5.7), and from 70 to 580 microns in caliber (mean, 345.8 microns). The average caliber of all the TG vessels per posterior cerebral artery ranged from 700 to 3400 microns (mean, 1972 microns). The TG arteries most often originated as individual vessels; however, in 26.67% of the hemispheres examined they shared a common site of origin, and 33.33% of the hemispheres they arose from common stems. The common stems ranged from 320 to 800 microns in diameter (mean, 583 microns). The TG branches arose from the crural or ambient (P2) segment of the posterior cerebral artery in 80% of the hemispheres, from the P2 and the quadrigeminal (P3) segment in 20%, from both the distal segment of the posterior cerebral artery and the common temporal artery (13.33%), or from the distal segment and either the calcarine (3.33%) or parieto-occipital artery (3.33%). The TG arteries usually penetrated the medial geniculate body (100%), pulvinar thalami (80%), brachium of the superior colliculus (53.33%), or lateral geniculate body (13.33%). The collateral branches of the TG arteries were noted to reach the medial geniculate body (76.67%), pulvinar (70%), brachium of the superior colliculus (40%), crus cerebri (40%), and lateral geniculate body (6.67%). The anastomoses were present in 66.67%, usually between the TG vessels and the medial posterior choroidal artery (33.33%), or the mesencephalothalamic artery (26.67%). They ranged in number from 1 to 3 (mean, 1.2), and in caliber from 90 to 400 microns (mean, 197 microns).(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral Arteries↗

PubMed1989

Removal of an arteriovenous malformation in the optic chiasm. A case of Bonnet-Dechaume-Blanc syndrome without retinal involvement.

A rare case of an arteriovenous malformation involving the optic chiasm associated with vascular anomaly in the left maxillary region is presented. The angiogram demonstrated an arteriovenous malformation arising from the anterior circle of Willis (internal carotid, posterior communicating, and proximal anterior cerebral arteries), and located in the region of the optic chiasm and hypothalamus. The case was diagnosed as the Bonnet-Dechaume-Blanc syndrome without intraorbital and retinal arteriovenous malformations. The suprasellar arteriovenous malformation was removed, except for a small portion in the hypothalamus, with satisfactory results.

Adolescent↗

PubMed1989

Carotid cave aneurysms of the internal carotid artery.

In a series of 32 surgical cases of carotid-ophthalmic artery aneurysm, seven of the lesions were located in the "carotid cave." This special type of aneurysm is usually small and projects medially on the anteroposterior view of the angiogram. At surgery, it is located intradurally at the dural penetration of the internal carotid artery (ICA) on the ventromedial side, appears to be buried in the dural pouch (carotid cave), and is often difficult to find, dissect, and clip. The aneurysm extends into the cavernous sinus space, and the parent ICA penetrates the dural ring obliquely. An ipsilateral pterional approach was used in all 32 cases, and ring clips were used exclusively because the aneurysms were located ventromedially. Clipping was successful in five cases. All patients returned to their preoperative occupation, although vision worsened postoperatively in two cases. The technical steps required for successful obliteration of this aneurysm are summarized as follows: 1) exposure of the cervical ICA; 2) unroofing of the optic canal and removal of the anterior clinoid process; 3) exploration of the ICA around the dural ring and opening of the cavernous sinus; 4) direct retraction of the ICA and optic nerve; and 5) application of multiple ring clips to conform to the natural curvature of the carotid artery; a curved-blade ring clip is especially useful. The relevant topographic anatomy is discussed.

Adult↗

PubMed1988

Microsurgical anatomy of the arteries of the pituitary stalk and gland as viewed from above.

The microsurgical anatomy of the arteries of the pituitary stalk and gland as viewed from above was studied in 50 adult cadaveric hemispheres using the operating microscope. There were three types of vessels to the pituitary from above: the superior hypophyseal artery originating from the internal carotid artery, the infundibular artery from the posterior communicating artery, and the prechiasmal artery from the ophthalmic artery. The superior hypophyseal artery originated from the medial to posterior aspect of the internal carotid artery. The average number of vessels of the superior hypophyseal artery was 2.2 per hemisphere, and the diameter was 0.25 mm on average. The majority (76%) of superior hypophyseal arteries arose from the proximal half of the segment between the origins of the ophthalmic and posterior communicating arteries of the internal carotid artery. The infundibular artery originated mainly from the medial side (69%) of the posterior communicating artery. Its diameter was 0.22 mm, and number 0.23 per hemisphere. The number of prechiasmal arteries was 0.06 per hemisphere. As a result, there were on average 2.5 vessels per hemisphere, totally 5 per brain, with the average diameter 0.25 mm, supplying the pituitary stalk and gland from above. The clinical application of these anatomical data to the diagnosis and treatment of suprasellar tumours and carotid-ophthalmic aneurysms is discussed.

Arteries↗

PubMed1988

[Werner's syndrome associated with meningioma: case report].

We present two cases of Werner's syndrome associated with intracranial meningioma. Characteristic clinical features of Werner's syndrome include short stature with slender extremities, premature senility, juvenile cataract, skin changes, a tendency to diabetes mellitus and familial occurrence. A 44-year-old female, who had been treated for diabetes mellitus, was diagnosed as having Werner's syndrome because of various characteristic features. A falx meningioma was incidentally found on CT scan, and was surgically removed. Her diabetes mellitus improved. The second case was a 28-year-old male was diagnosed as having Werner's syndrome, diabetes mellitus, juvenile cataract, together with diabetes insipidus, and liver dysfunction. He developed severe headache, gait disturbance and then became unconscious with right hemiparesis. He was found to have a parasagittal meningioma by CT scan and angiography. After removal of the tumor, diabetes mellitus, diabetes insipidus and liver dysfunction improved. The reported incidence of neoplasms associated with Werner's syndrome is about 10%. The majority of associated tumors were mesenchymal in origin. Ten meningiomas, 1 neurinoma and 2 gliomas are reported as associated tumors in the central nervous system. Most of the associated meningiomas were asymptomatic and found incidentally at autopsies or CT scans. Diabetes mellitus associated with Werner's syndrome is generally mild with high immunoreactive insulin value and is controllable by diet therapy and oral antidiabetic drugs. Daily profile of blood sugar improved after the removal of tumor in our cases. In 50 gm glucose tolerance test, tendency of delayed appearance of peak value, which is common in Werner's syndrome, was not altered in our cases. Discussion is made as to the association of Werner's syndrome with meningioma and diabetes mellitus.

Adult↗