Superficial Sylvian Vein Research Articles

Biocompatibility of Plastic Clip in Neurocranium - Experimental Study on Dogs.

A potential advantage of the use of the plastic clips in neurosurgery is their property of causing fewer artifacts than titanium clips as assessed by computed tomography and magnetic resonance scans. The biocompatibility of plastic clips was demonstrated in the peritoneal cavity, but their behavior in the neurocranium is not known. Twelve aggressive stray dogs designated for euthanasia were taken for this experimental study. The animals were divided into two groups. In all cases, after anesthesia, a craniotomy was performed, and after opening the dura, a proximal part titanium clip was placed on the isolated superficial Sylvian vein (a permanent Yasargil FT 746 T clip at a 90° angle, while a plastic Hem-o-lok clip ML was placed on another part of the vein). The first group of animals was sacrificed on the 7 < sup > th < /sup > postoperative day and the second group on the 60 < sup > th < /sup > postoperative day. Samples of tissue around the clips were taken for a histopathological evaluation. The plastic clip caused a more intensive tissue reaction than the titanium clip on the 7 < sup > th < /sup > postoperative day, but there was no statistical difference. Even on the 60 < sup > th < /sup > postoperative day there was no significant difference in tissue reaction between the titanium and plastic clips. These preliminary results confirm the possibility for the use of plastic clips in neurosurgery. Before their use in human neurosurgery, further studies are needed to investigate the long-term effects of the presence of plastic clips in the neurocranium, as well as studies of the aneurysmal model.

Indocyanine green videoangiography for assessment of postoperative hyperperfusion in moyamoya disease

Postoperative cerebral hyperperfusion (HP) is a notable complication that occurs more frequently in moyamoya disease (MMD) than in atherosclerosis. This study aimed to clarify the characteristics of intraoperative indocyanine green (ICG) videoangiography in MMD and atherosclerotic disease in terms of postoperative HP. This prospective study included 47 patients with 60 sides that underwent superior temporal artery (STA)-middle cerebral artery (MCA) single bypass. ICG videoangiography was performed after revascularization. The ICG time intensity curve was recorded in the STA, proximal MCA, distal MCA, and superficial Sylvian vein, and the angiographic differences among adult MMD, pediatric MMD, and atherosclerosis were analyzed. Twenty-two patients (27 sides) had adult MMD, 14 patients (22 sides) had pediatric MMD, and 11 patients (11 sides) had atherosclerosis. Postoperative HP was significantly higher in adult MMD (40.7%) than in pediatric MMD (18.2%) and atherosclerosis (0%). Adult MMD with HP was associated with a longer ICG peak time (P < 0.001). There was no correlation between the ICG peak time and preoperative cerebral blood flow or vascular reserve. The ratio of the vessel caliber was also higher in adult MMD with HP (P < 0.001). ICG videoangiography provides different characteristics of bypass flow among adult MMD, pediatric MMD, and atherosclerosis. Poor run-off and stagnation of blood flow from the STA might contribute to postoperative HP in MMD. The occurrence of postoperative HP in MMD could depend on two factors: donor STA size and poor run-off and integrity of the blood brain barrier in the recipient MCA.

Abstract T MP36: Indocyanine Green Videoangiography for Assessment of Postoperative Hyperperfusion in Moyamoya Disease

Introduction: Postoperative cerebral hyperperfusion (HP) is a notable complication that occurs more frequently in moyamoya disease (MMD) than in atherosclerosis of unknown etiology. This study aimed to clarify the characteristics of intraoperative indocyanine green (ICG) videoangiography in MMD and atherosclerotic disease in terms of postoperative HP. Methods: This prospective study included 47 patients with 60 sides that underwent superior temporal artery (STA)-middle cerebral artery (MCA) single bypass. ICG videoangiography was performed after revascularization. The ICG time intensity curve was recorded in the STA, proximal MCA, distal MCA, and superficial Sylvian vein, and the angiographic differences among adult MMD, pediatric MMD, and atherosclerosis were analyzed. Results: Twenty two patients (27 sides) had adult MMD, 14 patients (22 sides) had pediatric MMD, and 11 patients (11 sides) had atherosclerosis. Postoperative HP was significantly higher in adult MMD (40.7%) than in pediatric MMD (18.2%) and atherosclerosis (0%). Adult MMD with HP was associated with a longer ICG peak time (P&lt;0.001). There was no significant difference in ICG peak time among presentations in MMD, and no correlation between ICG peak time and preoperative hemodynamic parameters. The ratio of the vessel caliber was also higher in adult MMD with HP (P&lt;0.001). Conclusions: ICG videoangiography provides different characteristics of bypass flow among adult MMD, pediatric MMD, and atherosclerosis. Poor distribution and run-off of blood flow from the STA might contribute to postoperative HP in MMD. The occurrence of postoperative HP in MMD could depend on two factors: host STA size and recipient MCA integrity.

Isolated Superficial Sylvian Vein Thrombosis With Long Cord Sign: Case Report and Review of the Literature

Isolated cortical vein thrombosis (ICVT) is extremely rare. Only single case or small series of ICVT have been reported; clinical details are still uncertain. We report a case of isolated superficial sylvian vein thrombosis with exceedingly long cord sign. A 14-year-old female with severe sudden onset headache visited our hospital. Fluid attenuated inversion recovery and echo-planar T2* susceptibility-weighted imaging (T2*SW) showed a long cord sign on the surface of the sylvian fissure. The patency of dural sinuses and deep cerebral veins were confirmed by magnetic resonance venography (MRV), and diagnosis of ICVT was made. She recovered completely without anticoagulant agents. To clarify the clinical characteristics of ICVT, we reviewed 51 ICVT cases in the literature. In many cases, T2*SW was the most useful examination to diagnose ICVT. In contrast with general cerebral venous thrombosis, MRV and conventional angiography were either supporting or useless. Anastomotic cortical veins were involved frequently; symptoms of gyri around the veins were common. It also suggested that ICVTs of the silent area might have been overlooked because of nonspecific symptoms, and more patients with ICVT may exist. In cases involving patients with nonspecific symptoms, the possibility of ICVT should be considered.

Contemporary Angiographic Assessment and Clinical Implications of the Vein of Labbé in Neurotologic Surgery

To better understand the drainage patterns of the 3 largest superficial anastomotic veins (SAVs), namely, vein of Labbé (VL), the vein of Trolard (VT), and the superficial sylvian vein (SSV). To assess the dominance of the VL in the superficial cortical venous system, because this vein may be encountered in neurotologic surgery and its interruption may result in a venous infarct of the temporal lobe. The database of the radiology department at the University of Cincinnati was used to identify all patients who underwent a diagnostic angiographic study between September 1, 2009, and January 1, 2010. Studies were excluded if there were intracranial masses or vascular lesions. Angiograms were assessed for the presence of the VL, VT, and SSV, as well as vessel dominance, determined by their relative calibers. A total of 101 patients (81%) underwent bilateral and 48 unilateral angiography, for a total of 250 studies. Mean age was 55 years (range, 16-83 yr). Seventy-seven patients (53%) were females. The most common pattern observed was the presence of all 3 SAVs (78%). The VL was absent or poorly developed in 34 studies (14%) and was the dominant superficial vein in 51 (20%), of which 28 (55%) occurred on the right. Considerable variability is demonstrated in the drainage patterns of the SAVs. Care should be taken in neurotologic surgery to avoid injuring the VL because this may represent the single dominant drainage pathway of the lateral surface of the temporal lobe in a large number of patients.

Dural Arteriovenous Fistula Between Inferolateral Trunk of the Internal Carotid Artery and Superficial Sylvian Vein -Case Report-

A 40-year-old Brazilian man presented with headache followed by consciousness disturbance. Computed tomography showed subarachnoid hemorrhage with right frontal hematoma. Angiography revealed a dural arteriovenous fistula (dAVF) fed by the inferolateral trunk of the internal carotid artery and draining into the superficial sylvian vein with varix formation. The shunting point was directly obliterated through a pterional approach. Postoperative angiography showed complete disappearance of the fistula. A ventriculoperitoneal shunt was needed for normal pressure hydrocephalus during his hospitalization. The modified Rankin scale at discharge was grade 2 with mild cognitive dysfunction. This case of dAVF may represent congenital dAVF.

Traumatic Carotid Cavernous Fistula Complicated With Intracerebral Hemorrhage -Case Report-

A 45-year-old woman presented with a rare case of traumatic carotid cavernous fistula (CCF) complicated with intracerebral hemorrhage after injury in a car accident. She had multiple injuries including facial bone fracture and slight subarachnoid hemorrhage around the left sylvian fissure. Emergent plastic surgery for the facial deformity was performed. Next day, she suffered intracerebral hemorrhage in the left frontal lobe. Angiography revealed CCF, predominantly draining to the left superficial sylvian vein. The left internal carotid artery was occluded by endovascular treatment. The clinical triad of traumatic CCF is orbital bruit, exophthalmos, and chemosis. Hemorrhagic complication such as subarachnoid hemorrhage, epistaxis, and otorrhagia may occur according to the venous drainage pattern. Traumatic CCF may be accompanied by intracerebral hemorrhage.

De Novo Intracranial Pial Arteriovenous Fistula After Craniotomy

Background We describe the case of a patient who developed intracranial pial arteriovenous fistulae near the site at which oxidized regenerated cellulose (ORC) was applied to promote hemostasis during a prior surgery. Case Description The patient was a 67-year-old woman who had undergone craniotomy for treatment of an unruptured aneurysm. Intraoperatively, the patient experienced bleeding from the superficial sylvian vein, and ORC was applied to the site to promote hemostasis. Twenty-one months later, magnetic resonance imaging demonstrated abnormal flow voids in the left sylvian fissure. Cerebral angiography showed a vascular anomaly fed by the left middle cerebral arteries and draining into the left sylvian veins. The vascular lesion was located in the region at which ORC was applied during the previous surgery. The patient underwent neurological and neuroradiological assessments every 4 months without treatment. The last magnetic resonance imaging performed 46 months after the previous surgery showed no interval changes of the lesions. Conclusions ORC may be associated with development of intracranial pial arteriovenous fistulae.

手術手技の工夫 Ｄｉｓｔａｌ ｓｙｌｖｉａｎ ａｐｐｒｏａｃｈにおけるｓｕｐｅｒｆｉｃｉａｌ ｓｙｌｖｉａｎ ｖｅｉｎ剥離の工夫―Ｓｕｒｇｉｃａｌ ａｎａｔｏｍｙからの検証―

While the pterional approach is one of the most used approaches, there are variations. We have practiced the distal sylvian approach by dissection between the superficial sylvian veins. To evaluate the appropriateness and rationale of this approach, we investigated the microsurgical anatomy of the superficial sylvian vein and the frontal and temporal bridging veins. Of 76 consecutive patients with a cerebral aneurysm clipped by the distal sylvian approach, significantly more had a frontal bridging vein (79%) than a temporal bridging vein (54%; p＜0.01). The superficial sylvian vein tended to influx into the main trunk of the frontal side rather than the temporal side. These results show that dissection between the superficial sylvian veins preserves the frontal bridging vein, which has a high prevalence, and dissection of the temporal side of the superficial sylvian veins is more effective.

Supratentorial craniotomy complicated by an homolateral remote cerebellar hemorrhage and a controlateral perisylvian infarction: case report

The authors present the case of a 49-year-old male patient with a right remote cerebellar hemorrhage and left perisylvian venous infarction complicating a right supratentorial craniotomy for temporal meningomia resection. These two events may result from a functional stenosis (due to perioperative brainstem sag) of the junction between the vein of Galen and the straight sinus. Remote cerebellar hemorrhage could then be explained by infarction in the territory of cerebellar veins emptying in the vein of Galen, and the left perisylvian infarction could be caused by venous infarction in the territory of a dominant superficial sylvian vein emptying in the basal vein. This hypothesis could shed light on the pathophysiology of remote cerebellar hemorrhage.

Superficial Anastomotic Veins: Neurosurgical View Depending on 251 Cranitotomies

Superficial anastomotic veins (SAVs) have been studied extensively but little attention has been paid to clinical studies. The aim of this study is to provide variations in the drainage patterns of SAVs depending on the intraoperative findings. A total of 251 craniotomies due to intractable temporal lobe epilepsy were performed between 1972 and 1987 at the Montreal Neurological Institute. The courses of the three largest SAVs including the vein of Trolard (VT), vein of Labbe (VL) and superficial Sylvian vein (SSV) were studied. All three veins showed variable courses. The most common predominant vein was the combination of the VL + SSV. The VT and VL were frequently coursed at the level of the central vein and middle temporal vein, respectively. On the right hemisphere the SSV was the predominant type while the VL tended to be predominant on the left hemisphere. A combination of VL and SSV was predominant in patients with right and/or left hemispheric dominance. The SAVs showed considerable variation in their courses and it is difficult to define an exact pattern although some courses showed constant directions. Attention should be paid not to damage these veins since in a considerable number of cases a single dominant vein may be responsible for draining a majority of the lateral surface of cerebral hemisphere.

Serial Angiography of Dynamic Changes of Traumatic Middle Meningeal Arteriovenous Fistula -Case Report-

A 48-year-old woman suffered head trauma and presented with an acute epidural hematoma with a linear fracture of the right temporal bone across the middle meningeal groove. Initial angiography demonstrated no vascular abnormalities. Eight months later, she again suffered head trauma and computed tomography demonstrated traumatic subarachnoid hemorrhage. Right external carotid angiography revealed a middle meningeal arteriovenous fistula (AVF) which drained into the superficial sylvian veins via the sphenoparietal sinus. Serial angiography showed progressive dilation of the draining veins, but she refused surgical intervention and dropped out of our outpatient clinic. Fifteen years after the first head trauma, she presented with subarachnoid hemorrhage. Angiography demonstrated formation of venous aneurysms on the drainer of the AVF. The dilated superficial sylvian vein was removed together with the ruptured venous aneurysm. Histological examination of the drainer revealed an arterialized vein. The serial angiographic evaluations revealed dynamic changes of the traumatic middle meningeal AVF, including progressive dilation of the drainers, simplification of the drainage routes, and the formation of venous aneurysms, which presumably represents the entire natural course of traumatic middle meningeal AVF manifesting as hemorrhage. The present case of traumatic middle meningeal AVF with a deteriorating course suggests that surgical removal or embolization of the AVF is strongly indicated if follow-up angiography shows dilation of the drainers, which implies increased shunt flow.

Usefulness of Intravascular Ultrasonography Monitoring of Coil Embolization for Traumatic Direct Carotid-Cavernous Fistula -Case Report-

A 61-year-old woman was admitted for head injury after a traffic accident. Two months later, she developed abducens nerve palsy, chemosis, and pulsatile tinnitus. Right internal carotid angiography demonstrated a high flow direct carotid-cavernous fistula (CCF) at the C(5) portion with reflux into the superficial and deep sylvian veins, superior ophthalmic vein, superior petrosal sinus, and inferior petrosal sinus. Intravascular ultrasonography (IVUS) revealed a large fistula at the C(5) portion of the internal carotid artery (ICA). Coil embolization via transarterial and transvenous approaches under IVUS monitoring was performed. During the procedure, IVUS accurately detected protrusion of a coil into the parent ICA, and the parent artery could be preserved. IVUS monitoring is useful for embolization of direct CCF with coils.

手術トレーニング 手術トレーニングにおけるｄｉｓｔａｌ ｔｒａｎｓｓｙｌｖｉａｎ ａｐｐｒｏａｃｈの意義と安全性

We discuss the usefulness of a distal transsylvian (DTS) approach for microsurgical training of young neurosurgeons and assess the safety of this procedure by evaluating the complication ratio in our institute. In this procedure, residents learn the vulnerability of the pia mater, pial capillary vessels and small superficial sylvian veins and acquire the skill to avoid bleeding from these structures. In addition, if these vulnerable structures bleed, they learn how to keep the field dry by using suction or hemostatic materials without bipolar coagulation. These represent basic skills for dissecting the neck of an aneurysm safely and preserving critical perforators and nerves, which are the most vulnerable structures in aneurysmal surgery. From 1993 to 2008, this approach was used by 17 residents in 225 procedures. No morbidity or mortality caused by this procedure was observed. For young neurosurgeons, the DTS approach is one of the best training methods to acquire delicate microsurgical skills that cannot be acquired in conventional off-the-job training.

Clinical and angiographic characteristics of cavernous sinus dural arteriovenous fistulas manifesting as venous infarction and/or intracranial hemorrhage

Cavernous sinus (CS) dural arteriovenous fistulas (DAVFs) rarely cause venous infarction (VI) and/or intracranial hemorrhage (ICH) despite the presence of cortical venous drainage (CVD). The present study investigated the characteristics of CS DAVFs manifesting as VI/ICH. Fifty-four patients treated for CS DAVFs were retrospectively studied. Six patients presented with VI/ICH. Two of the three patients presenting with ICH had CVD only to the superficial sylvian vein (SSV) or the deep sylvian vein (DSV). Three patients presenting with VI had multiple drainages, and angiography of these patients showed a varix on the SSV, drainage into the DSV with agenesis of the second and third segment of basal vein of Rosenthal, and thrombosis of the distal petrosal vein. CS DAVF with CVD only carries higher risk of VI/ICH than multiple drainages. Many CS DAVFs presenting with VI, especially those with drainage into the petrosal vein, have multiple drainages in the early stage. Thrombosis of the inferior and superior petrosal sinuses and superior orbital vein gradually increases pressure of the CVD, and then, VI may occur. In contrast, CS DAVFs with CVD only from the beginning, common in the patients with drainage into the SSVs and DSVs, are likely to cause ICH. Angiographic risk factors causing VI/ICH are CVD only, varix formation, agenesis of the second and third segment of basal vein of Rosenthal, and thrombosis of the superior orbital vein, lateral half of the superior petrosal sinus, and distal CVD.

Plical resection in pre-temporal approach for basilar bifurcation aneurysms: preliminary surgical experience and cadaveric study

Although a pre-temporal approach (PA) can provide a wide space for preservation of thalamoperforating atrteries in direct surgery for basilar bifurcation aneurysms (BBAs), it cannot always secure adequate proximal control. The authors described the advantages of plical resection added to PA for BBAs. Between October 1998 and April 2000, eight consecutive patients with BBAs were treated in the neurosurgical department of Kurashiki Central Hospital. Among them, five patients received direct clipping using this method. There were four females and one male, ages ranging from 61 to 77 (mean 70.8 years). Mean aneurysmal size and distance between the in"terclinoidal line and the aneurysmal neck was 4.5 and 9.5 mm, respectively. The operative procedures consisted of the following components; 1) fronto-temporal craniotomy with translocation of orbito-zygomatico-malar bone for PA, 2) preservation of lateral branches of the superficial sylvian veins, 3) resection of plica dural folds to increase the operative field up to the oculomotor nerve (OMN). Complete clipping was achieved without thalamic infarction or temporal contusion in all patients. Three of the five patients suffered from transient right OMN palsy which recovered within two months after surgery. Plical resection in the pre-temporal approach might be beneficial in the surgical treatment of BBAs when proximal control seems difficult.

Microsurgical anatomy of the insula and the sylvian fissure.

The purpose of this study was to define the topographic anatomy, arterial supply, and venous drainage of the insula and sylvian fissure. The neural, arterial, and venous anatomy of the insula and sylvian fissure were examined in 43 cerebral hemispheres. The majority of gyri and sulci of the frontoparietal and temporal opercula had a constant relationship to the insular gyri and sulci and provided landmarks for approaching different parts of the insula. The most lateral lenticulostriate artery, an important landmark in insular surgery, arose 14.6 mm from the apex of the insula and penetrated the anterior perforated substance 15.3 mm medial to the limen insulae. The superior trunk of the middle cerebral artery (MCA) and its branches supplied the anterior, middle, and posterior short gyri; the anterior limiting sulcus; the short sulci; and the insular apex. The inferior trunk supplied the posterior long gyrus, inferior limiting sulcus, and limen area in most hemispheres. Both of these trunks frequently contributed to the supply of the central insular sulcus and the anterior long gyrus. The areas of insular supply of the superior and inferior trunks did not overlap. The most constant insular area of supply by the cortical MCA branches was from the prefrontal and precentral arteries that supplied the anterior and middle short gyri, respectively. The largest insular perforating arteries usually arose from the central and angular arteries and most commonly entered the posterior half of the central insular sulcus and posterior long gyrus. Insular veins drained predominantly to the deep middle cerebral vein, although frequent connections to the superficial venous system were found. Of all the insular veins, the precentral insular vein was the one that most commonly connected to the superficial sylvian vein.

Preoperative evaluation of the venous system for potential interference in the clipping of cerebral aneurysm

Background Variations of the venous system affecting the surgical treatment of cerebral aneurysm were evaluated using three-dimensional computed tomography angiography (3D-CTA) to evaluate the essential aspects of preoperative diagnosis. Methods This study included 50 patients who underwent clipping of cerebral aneurysm through the pterional and trans-sylvan approaches. The 3D-CTA and operative findings were compared to assess the characteristics of cases in which the veins restrict brain retraction, hinder operative manipulations or require sacrifice because of the position in the operative field. Results Superficial sylvian veins that restricted brain retraction were identified in 8 cases. The veins entered the cavernous sinus in a relatively high position just below either the sphenoid ridge (superior lateral type) or the anterior clinoid process (superior medial type), and the veins entering at a more medial position were closer to the spatula and tended to be compressed or directly excluded (superior medial type). The inferior medial type did not tend to become tense and so did not restrict brain retraction. The inferior lateral type hardly affected the operative manipulation. The first segment of the basal vein of Rosenthal, the uncal vein entering the cavernous sinus, or the sphenoparietal sinus were located in the operative field in six cases, and affected the manipulation of dissecting arteries, and exposure and clipping of the aneurysm. Conclusions 3D-CTA provides essential information for operative planning to protect the venous system during the pterional and trans-sylvian approaches.

Operative anatomy and classification of the sylvian veins for the distal transsylvian approach.

Methods for preservation of the sylvian veins in the transsylvian approach have not been established because of the considerable variations. This study attempted to classify the sylvian veins to facilitate systematic dissection of the sylvian fissure for sylvian veins to be preserved. The operative anatomy of the sylvian vein was examined in 82 hemispheres. The type of drainage and the pattern of branching were investigated. The superficial sylvian vein (SSV) was classified into three types according to the number of stems draining into the dural sinus on the inner surface of the sphenoid bone: The SSV was absent or hypoplastic in eight cases, the SSV was single in 38 cases, and the SSV was double in 36 cases. The SSV drained into neither the sphenoparietal sinus nor the cavernous sinus in nine cases. An anastomosis between the SSV and the deep middle cerebral vein (DMCV) was observed in 42 cases. The frontobasal bridging vein (FBBV) drained into the sphenoparietal sinus in 47 cases. The type of connection was further subdivided into four types according to the connections with the DMCV and FBBV. The venous anatomy of sylvian fissure indicates that dissection (skeletonization) of the main stem of sylvian veins from the temporal lobe should be performed to preserve the tributaries from the frontal lobe.

内頚動脈後向きの動脈りゅうに対するｔｒａｎｓｓｙｌｖｉａｎ ａｐｐｒｏａｃｈの変法としてのａｎｔｅｒｉｏｒ ｔｅｍｐｏｒａｌ ａｐｐｒｏａｃｈ

Because ventrally directing IC aneurysm is sometimes difficult to treat by the standard pterional approach, we attempted to modify our distal transsylvian approach. We describe this modified distal transsylvian approach (anterior temporal approach) in this paper. The surgical method comprises the following steps; 1. Superficial sylvian veins are displaced to the frontal side of the fissure without sacrificing those veins. An anastomotic trunk of the deep middle cerebral vein is dissected from the medial temporal lobe. 2. A posterior division of M2 segment, M1 segment and anterior temporal artery are dissected from the medial temporal lobe. 3. Arachnoid trabecula between the uncus and the anterior choroidal artery is incised. This allows posterolateral retraction of the temporal pole without significant retraction. Although the anterior temporal approach is employed for the surgical treatment of distal BA aneurysm, it is also available for the IC ventral aneurysm.