A 3D-Computed Tomography Angiography Study to Help in Surgical Planning for Retrosigmoid Craniotomies

Aims and Objectives: It is impossible to precisely anticipate the course of the transverse and sigmoid sinuses and theirindividual relationship to superficial landmarks such as the asterion during retrosigmoid approaches. This study was done todetermine the position of the asterion and the relationship between asterion and the transverse-sigmoid sinus junction (TSSJ)in making precise burr hole without damaging sinuses during retrosigmoid craniotomies.Materials and Methods: Computed tomography (CT) angiography was performed in 50 patients to obtain 3D-CT volumerendering images of cranial bone and dural sinuses. After delineating the sinuses, by simple restructuring using software andopacity modulation, bone image is reinforced. Asterion type, distance from the tip of mastoid process to asterion and root ofzygoma (ROZ) to asterion, and location of asterion in relation to TSSJ and distance between asterion and TSSJ were analyzedand measured.Results: The incidence of type 1 (presence of sutural bones) in our study was 24% and type 2 (absence of sutural bones) was76%. There was no statistically significance in the side and gender differences. The distance between the asterion and fromthe ROZ was 54.70 ± 3.68 on the right side and 54.32 ± 3.41 on the left side (P-0.612). The distance between asterion and tipof mastoid was 50.51 ± 2.67 on the right side and 50.12 ± 3.06 on the left side (P-0.716). The asterion was located on the T-Ssinus complex in 36 (72%) cases. The asterion was below the T-S sinus complex in 13 (26%) cases, and above the T-S sinuscomplex in only 1 (2%) cases.Conclusion: 3D-CT volume rendering imaging is capable of accurately visualizing the bony landmark and dural sinuses. Aneasy and simple restructured image provides precision and safety for the patient by ready and easy localization of asterionand TSSJ. This study was done to show that the previous cadaver-based anatomical studies can be done now in a moresophisticated and accurate manner with the latest technological advancements. This offers new options for anatomic researchand morphometric investigations.

Morphology And Morphometric Study On Anatomical Variations Of Jugular Foramen In Adult Human Skulls

Background: Jugular foramen, a large irregular foramen at the base of the skull , lies at the posterior end of petrooccipital suture between jugular process of occipital bone and jugular fossa of petrous part of temporal bone;above and lateral to foramen magnum. Many important structures pass through this foramen. Among these areInferior Petrosal Sinus, presence of three cranial nerves 9, 10, and 11 and Internal Jugular vein.The increasinguse of modern diagnostic procedures and new surgical approaches has created a need for much more detailedanatomical studies and explanations.Materials and Methods: The study was conducted in Osteology lab of Anatomy Department,KarpagaVinayagaInstitute of Medical Sciences, Chinnakolambakkam,Madurntakam taluk,Tamilnadu (India). 66 jugular foraminaof 33 Adult human skulls have been examined for study.Results and Conclusion: The morphometric and morphological analysis of jugular foramen were done in 33skulls, and the results obtained are mentioned below. The Mean average width of foramen is 15.26mm and theRange is between 10mm and 21mm. The Mean average length of foramen is 10mm and the Range is between 6mmand 14mm.Regarding, the size of the foramina; the Right side is larger than the Left side. Incomplete Intrajugularprocess is the commonest observation observed (in 64 foramina).Regarding,Intra Jugular Process contributionfor foramen, it is mainly from Temporal bone. Separate foramen for IPS was found only in one foramen out of 66foramina observed.The height of dome of jugular fossa is more on the Right than on the Left side (in 60.6% ofskulls).The range of Height of the Dome is 6.41mm to 18.46mm and the Mean average is 12.11mm.

An in vitro Experiment on Relationship Between Pulsatile Tinnitus and Temporal Bone Pneumatization Grade / 医用生物力学

Objective To study the relationship between pulsatile tinnitus and temporal bone pneumatization grade. Methods Through the in vitro experiment, the generation and transmission pathways of the venous sound were simulated. The sound signals at the position of eardrum were recorded and analyzed. Results In case of cortical plate dehiscence, the high pressure and pulse-synchronous venous sounds were received at eardrum. The highest sound pressure occurred in the normal pneumatization case. In case of cortical plate intactness, the non-pulsatile venous sounds with pressure close to the background control sound were received at eardrum. Temporal bone air cells (TBAC) with different pneumatization grades would transmit venous sound in different frequency ranges. Conclusions Normal pneumatization TBAC exhibited the highest amplification on venous sound, while hypopneumatization TBAC exhibited the lowest amplification on venous sound. The pneumatization grade of TBAC is neither the sufficient nor essential condition of pathogenic venous sound, while the cortical plate dehiscence is the sufficient or necessary condition of pathogenic venous sound.

CT and MRI findings of otogenic sigmoid sinus thrombophlebitis / 中国耳鼻咽喉头颈外科

OBJECTIVE To explore the CT and MRI appearances of otogenic sigmoid sinus thrombophlebitis(SST) and abscess. METHODS The HRCT, plain MRI, magnetic resonance venography(MRV), enhanced MRI findings in 11 patients with otogenic SST were retrospectively analyzed. RESULTS On CT, the bony wall of sigmoid sinus was eroded in 10 cases (10/11), and air bubbles were found in or around sigmoid sinus in 4 cases. On plain MRI, sigmoid sinus flow void effect disappeared in all 11 cases. SST manifested as high signal on T2W1 in all 11 cases, and as low signal on T1WI in 2 cases, isointense signal on T1WI in 6 cases, high signal on T1WI in 3 cases. Contrast enhancement MRI showed enhancement in wall of venous sinus, but venous sinus thrombosis did not enhanced, but showed as irregular filling defect or empty triangle. MRV showed that involved venous sinus was not visualized. CONCLUSION CT can show the erosion of the bony wall of sigmoid sinus which may indicate the SST; and if air bubbles are found around or in the sigmoid sinus, the abscess around or in the sigmoid sinus should be doubted. Conventional MRI combined with MRV are effective and noninvasive methods in the diagnosis of SST.

Influencing Factors Analysis of Facial Nerve Function after the Microsurgical Resection of Acoustic Neuroma

OBJECTIVE: To explore and analyze the influencing factors of facial nerve function retainment after microsurgery resection of acoustic neurinoma. METHODS: Retrospective analysis of our hospital 105 acoustic neuroma cases from October, 2006 to January 2012, in the group all patients were treated with suboccipital sigmoid sinus approach to acoustic neuroma microsurgery resection. We adopted researching individual patient data, outpatient review and telephone followed up and the House-Brackmann grading system to evaluate and analyze the facial nerve function. RESULTS: Among 105 patients in this study group, complete surgical resection rate was 80.9% (85/105), subtotal resection rate was 14.3% (15/105), and partial resection rate 4.8% (5/105). The rate of facial nerve retainment on neuroanatomy was 95.3% (100/105) and the mortality rate was 2.1% (2/105). Facial nerve function when the patient is discharged from the hospital, also known as immediate facial nerve function which was graded in House-Brackmann: excellent facial nerve function (House-Brackmann I–II level) cases accounted for 75.2% (79/105), facial nerve function III–IV level cases accounted for 22.9% (24/105), and V–VI cases accounted for 1.9% (2/105). Patients were followed up for more than one year, with excellent facial nerve function retention rate (H-B I–II level) was 74.4% (58/78). CONCLUSION: Acoustic neuroma patients after surgery, the long-term (≥1 year) facial nerve function excellent retaining rate was closely related with surgical proficiency, post-operative immediate facial nerve function, diameter of tumor and whether to use electrophysiological monitoring techniques; while there was no significant correlation with the patient’s age, surgical approach, whether to stripping the internal auditory canal, whether there was cystic degeneration, tumor recurrence, whether to merge with obstructive hydrocephalus and the length of the duration of symptoms.

Infantile Dural Arteriovenous Fistula of the Transverse Sinus Presenting with Ocular Symptoms, Case Reports and Review of Literature

Dural arteriovenous fistula (DAVF) of the transverse sinus with ophthalmic manifestations in young children are rare. We reviewed two cases of direct AVF of the transverse sinus with ocular manifestations managed at our institution. The first, a 2.5 years old male child presented with left exophthalmos. Angiography revealed AVF between the occipital artery and the transverse sinus. The second, a 2 years old female child, complained of left exophthalmos. Imaging studies showed bilateral direct AVFs of the transverse sinus with bilateral dysmaturation of the sigmoid sinus. Transarterial embolization was done in both cases. Clinical and radiological follow up revealed complete cure.This report suggests that DAVF of the transverse sinus supplied by the external carotid branches can present with ophthalmic manifestations especially if there is distal venous stenosis or obliteration involving sigmoid sinus. Transarterial embolization using coils and liquid embolic agents could be safe and feasible to obliterate the fistula.

Analysis of clinical characteristics of sigmoid sinus diverticulum / 中国耳鼻咽喉头颈外科

OBJECTIVE To analyze the clinical features of 8 patients with sigmoid sinus diverticulum and to improve the level of diagnosis and treatment. METHODS The tinnitus patients were asked in detail about the history, and performed a series of routine hearing tests (pure tone audiometry, acoustic impedance audiometry, otoacoustic emission inspection and brainstem auditory evoked potential (BAEP) etc.) and temporal bone HRCT scan. Eight cases were diagnosed with sigmoid sinus diverticulum, in which six cases undertook a surgery to reconstruct the sinus wall while the other 2 cases chose conservative treatment. RESULTS The diagnosis of 6 cases was proved to be correct by surgery, and the pulsatile tinnitus disappeared after reconstructing the sinus wall. No one recurred after following up from 2 to 12 months. Two cases of conservative treatment had no obvious improvement in symptoms. CONCLUSION Clinical manifestation, hearing examination, temporal bone CT/HRCT and Cranial CTA/CTV contributed to the diagnosis of sigmoid sinus diverticulum. Sinus wall reconstruction is a better approach.

The localization of the asterion according to the anatomical landmarks of posterior cranial fossa in newborns: clinical implications / Localización del asterión de acuerdo con los puntos anatómicos de la fosa craneal posterior en recién nacidos: implicaciones clínicas

The purpose of this study was to determine the localization of the asterion according to the anatomical landmarks of posterior cranial fossa and its relation with sinuses for posterolateral surgical approaches in newborns. On 70 head-halves, a needle about 2 mm with diameter was placed on the centre point of asterion (posterolateral fontanel) by inserting into the whole cranial bony tissue by forming an right angle with the bony surface. Various localizations of asterion and its measurements from the internal and external anatomical landmarks were investigated on term neonatal cadavers. The localization of asterion was found as on the sigmoid-transverse sinus junction (STJ) (5., 6., 7., 8. squares) in 40% of cases on right side and in 34%, on left side. Additionally, it was located below the STJ (9., 10., 11., 12. squares) in 60% of cases, on right side and in 63% of cases on left side. We determined that the most frequent localization of asterion as the 11. square both for the right and left sides 12 (34%) cases for the right side and 11 (31,4%) cases for the left side. The asterion was not located on 1., 2., 3., 4., 5. and 12. squares on right side and 1., 3., 4., 8. and 9. squares on left side. It has been found that the region of asterion has an average distance value of 19.9 mm to internal acoustic meatus (MI), 31.7 mm to posterior clinoid process (PC), 34.4 to dorsum sellae (DS), 19.2 mm to jugular foramen (FJ), 23.0 mm to hypoglossal canal (HC), internally. The distance of asterion as 28.8 mm to zygoma root (ZR) and 22.3 mm to Henle's spine (HS) and 15.8 mm to mastoid tip (MT) and 35.9 mm to external occipital protuberance (PE) were observed. By the guide of point asterion on newborns the area of 1cm2 on this point which was placed on superior 4 squares of our scale diagram is suggested as a safe area of placement of first burr hole to avoid from the risk of bleeding of sigmoid and transverse sinuses on craniotomies of posterior fossa.

El propósito de este estudio fue determinar la localización del asterion de acuerdo con los puntos anatómicos de la fosa craneal posterior y su relación con los senos de abordajes quirúrgicos posterolaterales en los recién nacidos. Fueron utilizadas 70 hemicabezas y se colocó una aguja de alrededor de 2 mm de diámetro en el punto central del asterion (fontanela posterolateral) en todo el tejido óseo craneal produciéndose la formación de un ángulo recto con la superficie ósea. La localización del asterion y las mediciones de los puntos de referencia anatómicos internos y externos fueron investigados en cadáveres de neonatos a término. La localización del asterion se encontró en la unión sinusal transverso sigmoide (STJ) (cuadrados 5., 6., 7., 8.) en el 40% de los casos en el lado derecho y en el 34%, en el lado izquierdo. Además, se encontró por debajo del STJ (cuadrados 9., 10., 11., 12.) en un 60% de los casos en el lado derecho y en el 63% de los casos en el lado izquierdo. Se determinó que la localización más frecuente del asterion fue 11., tanto para los lados derecho e izquierdo, 12 casos (34%) para el lado derecho y 11 casos (31,4%) para el lado izquierdo. El asterion no se encuentra en los cuadrados 1., 2., 3., 4., 5. y 12. del lado derecho y 1., 3., 4., 8. y 9. del lado izquierdo. Se determinó que la región del asterion tiene una distancia promedio de 19,9 mm al meato acústico interno, 31,7 mm al proceso clinoides posterior, 34,4 mm al dorso selar, 19,2 mm al foramen yugular y 23,0 mm al canal hipogloso, internamente. La distancia del asterion a la raíz del hueso cigomático fue 28,8 mm y 22,3 mm a la columna vertebral, siendo de 15,8 mm al proceso mastoides y 35,9 mm a la protuberancia occipital externa. En los recién nacidos, se sugiere un área de 1cm2 y se colocan en 4 casillas superiores de nuestro diagrama a escala, como una zona segura para la realización de la primera trepanación para evitar el riesgo de sangrado de los senos sigmoide y transverso en craneotomías de fosa posterior.

Early Spontaneous Recanalization of Sigmoid Sinus Thrombosis Following a Closed Head Injury in a Pediatric Patient : A Case Report and Review of Literature

Cerebral venous sinus thrombosis (CVST) following a closed head injury in pediatric patients is a rare condition, and an early spontaneous recanalization of this condition is extremely rare. A 10-year-old boy was admitted with a mild, intermittent headache and nausea five days after a bicycle accident. The brain computed tomography showed an epidural hematoma at the right occipital area with pneumocephalus due to a fracture of the occipital skull bone. The brain magnetic resonance imaging and the magnetic resonance venography demonstrated a flow signal loss from the right sigmoid sinus to the right jugular vein. The diagnosis was sigmoid sinus thrombosis, so close observations were selected as a treatment for the patient because of his gradually improving symptoms; however, he complained of vomiting 14 days the after conservative treatment. The patient was readmitted for a further examination of his symptoms. The laboratory and the gastroenterological examinations were normal. Due to concern regarding the worsening of the sigmoid sinus thrombosis, the brain magnetic resonance venography was rechecked and it revealed the recanalization of the venous flow in the sigmoid sinus and in the jugular vein.

Comparative morphometric study of the sigmoid sinus sulcus and the jugular foramen / Estudo morfométrico comparativo do sulco do seio sigmóideo e do forame jugular

Objective To compare the right and left sides of the same skulls as far as the described landmarks are concerned, and establish the craniometric differences between them. Method We carried out measurements in 50 adult dry human skulls comparing both sides. Results The sigmoid sinus width at the sinodural angle level was larger on the right side in 78% of the cases and at the level of the digastric notch in 72%. The jugular foramen width was also larger on the right side in 84% of the cases. The sigmoid sinus distance at the level of the digastric notch was larger on the right side in 64% of the cases, and the sigmoid sinus distance at the level of the digastric notch to the jugular foramen was larger on the right side in 70% of the cases. Conclusion Significant craniometric differences were found between both sides of the same skulls. .

Objetivo Comparar os lados direito e esquerdo no mesmo crânio nos pontos referenciais descritos e definir as diferenças craniométricas entre ambos. Método Realizamos mensurações em 50 crânios secos de humanos adultos comparando os lados direito e esquerdo. Resultados Como resultado, obtivemos as medidas da largura do seio sigmóideo na altura do ângulo sinodural maiores no lado direito em 78% dos casos e na altura do ponto digástrico em 72%. A largura do forame jugular foi também maior no lado direito em 84% dos casos. A distância do seio sigmóideo na altura do ângulo sinodural até a altura do ponto digástrico foi maior do lado direito em 64% dos casos, e a distância do seio sigmóideo na altura do ponto digástrico até o forame jugular foi maior do lado direito em 70% dos casos. Conclusão Diferenças craniométricas significativas foram encontradas entre os dois lados do crânio. .

Abordaje retrosigmoideo / Retrogigmoid approach

OBJETIVO: describir en forma detallada, paso a paso, la realización de un abordaje retrosigmoideo. DESCRIPCIÓN: posición: existen 3 posiciones descritas para la realización de este abordaje, semisentada, decubito dorsal y en banco de plaza. Incisión: se extiende desde la parte superior del pabellón auricular hasta 2 cm por debajo del vertice mastoideo, y 1 cm medial a la ranura digástrica. Disección de partes blandas: se realiza una disección subperiostica, teniendo especial cuidado con la vena hemisaria mastoidea (posible fuente de embolia aérea). Craniectomía: es necesario identificar previamente algunos puntos anatómicos de referencia para la ubicación de los senos transverso y sigmoides. En la etapa final de la remoción ósea, se procede al fresado de la porción más superior y lateral del abordaje, con la necesaria exposición de la porción inferior del seno transverso y de la porción medial del seno sigmoides. Apertura dural: se realiza una apertura en forma de letra "C" (lado izquierdo), o letra "C invertida" (lado derecho), con base medial, comenzando en la porción superior y medial de duramadre expuesta. Disección microquirúrgica: dependiendo de la ubicación de la patologia a abordar se debe realizar una retracción gentil del hemisferio cerebeloso hacia medial. En la mayoría de los casos es necesario abrir la cisterna cerebelobulbar, con el objeto de evacuar LCR. CONCLUSIÓN: el refinamiento alcanzado actualmente hace que el abordaje retrosigmoideo sea el más utilizado para el tratamiento de las múltiples patologías ubicadas en la región del ángulo pontocerebeloso. El acceso que proporciona esta vía a la mayoría de los nervios craneales que se encuentran en la fosa posterior, y a sus complejos neurovasculares correspondientes, lo convierte en un abordaje de obligatorio aprendizaje para todo neurocirujano

OBJECTIVE: the aim of this paper is to describe, step by step, the retrosigmoid approach to accessing the cerebellopontine angle (CPA). DESCRIPTION: patient position: three potential positions have been described for this approach: semi-sitting, dorsal decubitus and park bench. Incision: The incision extends from the top of the ear to 2 cm below the mastoid apex, and 1 cm medial to the digastric groove. Soft tissue dissection: A subperiosteal dissection is performed, taking special care to avoid the mastoid emissary vein. CRANIOTOMY: At the outset, it is necessary to identify certain anatomical landmarks to localize the transverse and sigmoid sinuses. Dural opening: The dural incision is made in the shape of the letter "C" on the left side or an inverted letter "C" on the right. Microsurgical dissection: Depending on the location of the pathology being treated, it may be necessary to perform gentle cerebellar retraction medially. CONCLUSIONS: the refinements now achieved with the retrosigmoid approach make it the most widely-used approach for the treatment of lesions located within the CPA. The access provided by this approach to the vast majority of the cranial nerves in the posterior fossa, as well as their neurovascular complexes, makes it a mandatory approach for all neurosurgeons to learn

Fatal Septic Internal Jugular Vein-Sigmoid Sinus Thrombosis Associated with a Malpositioned Central Venous Catheter

Septic internal jugular vein-sigmoid sinus thrombosis (IJV-SST) associated with a malpositioned central venous catheter is a rare condition. It is potentially life-threatening and necessitates early diagnosis and rapid administration of appropriate medications. Unfortunately, it is difficult to diagnose due to vague clinical presentations. Several studies such as CT, MRI, and cerebral angiography should be performed and carefully examined to help make the diagnosis. We report a case of septic IJV-SST due to a malpositioned central venous catheter.

Clinical Review of Chronic Otitis Media in Patients with Contracted Mastoid / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: High resolution computed tomography (HRCT) helps locating the anatomical structure within the temporal bone preoperatively. Contracted mastoid has lots of changed anatomical structure and outside in technique tympanomastoidectomy procedure cannot provide safe and effective access. The aims of this study are to analyze changed anatomical structure and to suggest safer and more effective surgical procedures in chronic otitis media patients with contracted mastoid. SUBJECTS AND METHOD: We measured distances between important surgical landmarks and cross sectional area of pneumatized air cells in contracted mastoid, and compared with normal groups. We analyzed postoperative complications between outside in technique and inside out technique tympanomastoidectomy. RESULTS: The shortest distance between the posterior wall of external auditory canal and the anterior edge of the sigmoid sinus, the vertical shortest distance between the superior wall of external auditory canal and the tegmen, and the cross-sectional area of mastoid air cells were significantly small in contracted mastoid group (p<0.05). There were 2 cases of postoperative facial weakness by outside in technique tympanomastoidectomy. CONCLUSION: Contracted mastoid has lots of changed anatomical structure. We suggest that inside out technique tympanomastoidectomy procedure is safer and more effective in patients with contracted mastoid.

The Experience of Ligation of Transverse or Sigmoid Sinus in Surgery of Large Petroclival Meningiomas

The authors present the experience of ligation of transverse or sigmoid sinus in the surgical removal of petroclival meningiomas. We reviewed the medical records and venograms of 14 patients with petroclival meningiomas, in whom the intraoperative ligation of transverse or sigmoid sinus had been done at our hospital between 1986 and 1999. All patients passed the intraoperative test clamping of the sinus. The drainage pattern of confluence of Herophili was classified into four types: type A, confluence and equal drainage on both transverse sinuses; type B, confluence and non-dominant transverse sinus on the tumor side; type C, confluence and dominant transverse sinus on the tumor side; and type D, unilateral transverse sinus only. Among the 14 cases, four cases were in type A, five cases in type B, and two were type C. There was no evidence of brain swelling after intraoperative test clamping of the sinus for more than 30 min. None of the patients experienced postoperative complications related with sinus ligation. Our observation suggests that the transverse or sigmoid sinus ligation is tolerable to patients sinus. who show the drainage patterns of type A, type B, and type C, if the test clamping proves to be safe.

Significance of Cerebral Venography in Surgery of Petroclival Meningiomas

OBJECTIVE: A thorough understanding of the related venous structure is mandatory for successful removal of the petroclival meningiomas. This study was planned to investigate the guideline for safe ligation and incision of transverse or sigmoid sinuses and the importance of drainage pattern of vein of Labb in surgical removal of petroclival meningiomas. MATERIALS AND METHODS: The authors reviewed the venogram of the consecutive 37 cases of petroclival meningiomas and retrospectively analyzed their surgical findings. The drainage pattern of confluence of Herophili was classified as Type A(confluent and equal on both sides), Type B(confluent and non-dominant on tumor side), Type C(confluent and dominant on tumor side) and Type D(unilateral drainage only) as these findings gave the information on safe ligation and resection of the sinus. Usefulness of intraoperative test clamping of sinus for safe ligation was also reviewed. The vein of Labb was analyzed with respect to its draining point and its collaterals to other superficial veins. RESULTS: Contraindications of the sinus ligation and resection according to the drainage pattern at the confluence of Herophili were Type C(n=10, 27%)and Type D(n=4, 11%). Patients with Type A(n=12, 32%)and Type B(n=11, 30%) were tolerable to sinus ligation ipsilateral to tumor, if the test clamping proved to be safe. Identification of no brain swelling, after intraoperative test clamping of the sinus for more than 30 minutes performed in 7 out of 11 cases, was a reliable indicator of safe sinus ligation. The drainage pattern of the vein of Labb, especially low-lying type, could predict the possibility of postoperative hemorrhage and infarction. Its drainage into tentorium or superior petrosal sinus, however, made the transtentorial approach impossible, leading to restricted operative field. CONCLUSION: For a successful removal of the petroclival meningiomas preoperative venogram should be examined carefully. The extent of exposure in a planned approach can be estimated by analyzing the variation of sinuses and the drainage pattern of vein of Labb.

A Fatal Complication Associated with Combined Posterior Petrous and Suboccipital Approach to a Giant Jugular Foramen Schwannoma

Schwannomas of the jugular foramen, originating from the glossopharyngeal nerve, vagus and accessory nerve represent approximately 0.17-0.72% of all intracranial tumor, and consists of 1.4-2.9% of all intracranial schwannomas. The clinical presentation of these tumors varies significantly according to originated nerve and it's growth pattern. Magnetic resonance(MR) image and temporal bone computed tomography(CT) scan have a major role for diagnosis of such tumor. The treatment of choice is total resection whenever possible. Generally, suboccipital approach is sufficient for the removal of the tumor, but in case with large size, combination of resection of petrous part of temporal bone with or without transection of sigmoid sinus is may be necessory. We have recently experienced one case of giant jugular foramen schwannoma and postoperative fatal complication in a 34-year-old male who was treated with combined posterior petrous and suboccipital approach with transection of sigmoid sinus.

Malformação arteriovenosa dural do seio transverso-sigmóide causando neuralgia trigeminal / Transverse-sigmoid sinus dural arteriovenous malformation presenting as trigeminal neuralgia

Os autores relatam um caso raro de malformação arteriovenosa dural (MAVD) do seio transverso-sigmóide esquerdo, causando neuralgia do trigêmeo. O paciente foi submetido a cirurgia para esqueletização do seio transversosigmóide com ressecção dos dois terços distais do seio transverso e dos dois terços proximais do seio sigmóide. O procedimento cirúrgico foi suficiente para proporcionar a cura angiográfica e clínica, com um seguimento de oito meses. Foi realizada uma completa revisão bibliográfica encontrando-se apenas cinco casos descritos de pacientes com MAVD e neuralgia trigeminal.

The authors report a rare case of transverse-sigmoid dural arteriovenousmalformation (DAVM) presenting as trigeminal neuralgia in the distribution of left V3. The patient was treated surgically by the sinus skeletonization technique with the resection of the distal 2/3 of the transverse sinus and the proximal 2/3 of the sigmoid sinus. Clinical and angiographic cure was achieved in our patient with a folow-up of 8 months. Furthermore, a thorough review of the English language literature was carried out, compiling only five cases of trigeminal neuralgia due to DAVM.

Combined Approach for Large CPA Tumor with Sacrifice of Sigmoid Sinus

With large CPA tumor(>3 mm), brain stem is usually displaced and distorted to contralateral side. It is important minimize retraction to protect brain stem and to lower morbidity. In our previous report, we reported the result and method of combined approach for large CPA tumor. In order to minimize brain stem retraction and to get good operating field, three of 7 cases of large CPA tumor with combined approach were operated with sacrifice of sigmoid sinus. The sigmoid sinus can be sacrificed if it can be angiographically verified that the sagittal sinus represents the major drainage to the contralateral sigmoid sinus. During operation, if pressure difference between before and after occlusion of sinus is less than 10 mmHg and any brain swelling does not develop after occlusion, the sigmoid sinus can be sacrificed.

"Dural A-V Malformation of Lateral and Sigmoid Sinus Associated with Intracerebral Hematoma" A Successfully Surgical Treated Case: Case Report

Most of dural arteriovenous malformations(AVM's) of lateral and sigmoid sinuses are known to acquired lesions evolving from a previously thrombosed dural sinus. Their clinical symptoms and signs are variable and their natural history is usually that of gradual progression and hence surgery is frequent necessary. The preferred surgical treatment is complete isolation or excision of the lesion. The authors have experienced 1 case of AVM's of lateral and sigmoid dural sinuses associated with intracerebral hematoma which was treated with complete excision of involved sinus with good result.

Morphometric Study on the Sigmoid Sinus of the Korean Adults / 체질인류학회지

The variations of the sigmoid sinus were studied in 50 Korean adults (average age 67). The classification of the shape and a measurement of the diameters of the sinus were done and the morpological. 1. The shape was classified into 4 types, and the round type was the most common in both sides. S shaped type was below 10% in both sides. 2. The breadth was regular in 54% of the right and in 70% of the left sinuses. According to the breadth change, the shape was classified into 4 shapes. 3. The average diameter was 8.6mm on the right side and 7.2mm on the left side. 4. Symmetry was present in 16% of all. 5. The right transverse sinus was absent in 1 case (2%) and the superior petrosal sinus did not open into the sigmoid sinus in 2 cases (4%). 6. Petrosqamous sinus was observed in 16%.