Pulsatile Tinnitus Due to a Large Mastoid Emissary Vein: Successfully Managed with Percutaneous Embolization in a Novel Approach.

Tinnitus refers to the perception of sound without any external stimuli which can be pulsatile or non-pulsatile. Dilated mastoid emissary vein (MEV) can cause pulsatile tinnitus. Herein, we report a case of persistent pulsatile tinnitus with dilated MEV managed successfully with percutaneous coiling of MEV in a 36 years male.

Novel technique utilizing polymethylmethacrylate cement for the treatment of pulsatile tinnitus caused by different sigmoid sinus pathologies.

PURPOSE: Sigmoid sinus anomalies such as dehiscence or diverticula may present with pulsatile tinnitus (PT) and low-frequency hearing loss. Occasionally, these symptoms are severe, necessitating resurfacing of the affected area to restore a normal-appearing sinus wall. This study describes three cases wherein we managed PT attributed to sigmoid sinus anomalies using polymethylmethacrylate (PMMA) bone cement, a novel material. METHODS: Three patients with PT without any history of illnesses initially underwent cortical mastoidectomy to expose the affected area and resurface the sinus wall. Subsequently, PMMA bone cement was used to reconstruct any bony defects causing PT symptoms. Viscosity of the bone cement was altered based on specific characteristics and causes of the affected area. Additionally, we performed the water occlusion test (WOT), audiological assessment, the Tinnitus Handicap Inventory score (THI), and temporal computed tomography, both pre- and postoperatively, to assess the extent of PT. RESULTS: Preoperatively, all three patients had tinnitus that dissipated with pressure on the neck and the water occlusion test (WOT), with no reported vertigo, trauma, or ear infections. Moreover, all three cases had a severe handicap according to the THI. In contrast, all cases had reduced PT and a significantly decreased THI score postoperatively, as well as no recurrence or complications and no instances of increased intracranial hypertension at the 12-month follow-up. CONCLUSION: All cases showed promising results, emphasizing the sustained benefits of this novel intervention for the management of PT.

Pipeline embolization device as a standalone curative approach for recurrent sigmoid sinus DAVF.

Dural arteriovenous fistulas (dAVFs) can occur as complications after surgical procedures, especially following the resection of meningiomas near the dural sinus. This case report presents a 74-year-old male who developed a recurrent sigmoid dAVF following meningioma resection. Initially treated with transvenous embolization and middle meningeal artery embolization, the dAVF recurred with worsening clinical symptoms. Conventional treatment options, including sinus sacrifice and transarterial embolization, were unsuitable due to the critical role of the patient's dominant right sigmoid sinus in cerebral venous drainage. Consequently, a reconstructive approach was employed using a pipeline embolization device (PED) construct. The PED successfully occluded the dAVF while preserving the function of the sigmoid sinus. A follow-up angiogram confirmed stable occlusion and normalization of intracranial venous drainage. This case underscores the potential of flow diversion as a viable treatment option for dAVFs, particularly in scenarios where preserving venous sinus function is paramount.

Topographic anatomy of the endolymphatic sac: a pilot cadaveric dissection study.

PURPOSE: The precise location of the endolymphatic sac (ES) may be difficult during surgical approaches. This morphometric study aimed to determine the exact location of ES in adult human cadavers for the management of pathologies such as Meniere's disease. METHODS: Twenty temporal bones of 10 adult cadavers (mean age: 70 ± 13.40 years, range: 45-92 years; sex: 4 males and 6 females) fixed with 10% formalin were bilaterally dissected to obtain numeric data about the location of ES. RESULTS: Distances of ES to the posterior semicircular canal (PSC), Donaldson line (DL), sigmoid sinus (SS) and sinodural angle (SA) were found as 2.76 ± 1.18 (0.96-5.58) mm, 1.74 ± 1.13 (0.58-5.07) mm, 2.30 ± 1.09 (0.54-4.91) mm and 16.04 ± 3.15 (9.82-22.18) mm, respectively. In addition, the angle between the tangents passing through the cortical bone (CB) and SS was determined as 35.37°±11.32° (21.30°-60.58°). No statistical difference was found between right-left or male-female measurements (p > 0.05). CONCLUSION: DL, SS, and PSC are essential anatomical landmarks for determining the location of ES. The spatial location of SS, including its depth to the cortical bone and the distance to anteriorly located anatomical structures of the mastoid cavity consisting of the facial nerve and PSC, is believed to be underlined for ES surgery. Our data may be used as a database to further define the relationship between ES and adjacent anatomical structures (SS, PSC, etc.) during the application of surgical approaches.

[Surgical technique and effect of the pulsatile tinnitus associated with sigmoid sinus on the dominant side of reflux].

Objective:To explore the effect of surgical treatment of the pulsatile tinnitus associated with sigmoid sinus on the dominant side of reflux. Methods:The clinical data of 43 patients with reflux dominant side pulsating tinnitus admitted by the same doctor from 2017 to 2023 were retrospectively studied to observe the curative effect of surgical treatment. Operation method: The sound insulation barrier was established by repair technique of bone wall defect of sigmoid sinus with "capping method", without changing the blood flow and blood vessel wall of sigmoid sinus. Results:No surgical complications occurred in all patients. During the follow-up period of 3 months to 6.9 years, 14 patients（32.6%） were cured, 18 patients（41.9%） were significantly effective, 4 patients（9.3%） were effective, and 7 patients（16.3%） were ineffective. The difference of tinnitus grade before and after surgery was statistically significant. Conclusion:In this group of cases, the sound insulation barrier was established by "capping method" technique of repairing bone wall defect of sigmoid sinus, which effectively avoided the disturbance of hemorheology status and vascular wall, thus avoiding the risk of venous wall stenosis and thrombosis on the dominant reflux side. The surgical method was easy to master, and the curative effect was significant, which was worthy of clinical promotion.

Flow Analysis of Central Venous Outflow Tract: A New Approach to Understanding Pulse-Synchronous Tinnitus.

OBJECTIVE: Pulse-synchronous tinnitus (PST) has been linked to multiple anatomical variants of the central venous outflow tract (CVOT) including sigmoid sinus (SS) dehiscence and diverticulum. This study investigates flow turbulence, pressure, and wall shear stress along the CVOT and proposes a mechanism that results in SS dehiscence and PST. STUDY DESIGN: Case series. SETTING: Tertiary Academic Center. METHODS: Venous models were reconstructed from computed tomography scans of 3 patients with unilateral PST. Two models for each patient are obtained: a symptomatic and contralateral asymptomatic side. A turbulent model-enabled commercial flow solver was used to simulate the pulsatile blood flow over the cardiac cycle through the models. Fluid flow through the transverse and SS junction was analyzed to observe the velocity, pressure, turbulent kinetic energy (TKE), and shear stress over a simulated cardiac cycle. RESULTS: Fluid flow on the symptomatic side showed increased vorticity in the presence of an SS diverticulum. Higher TKE with periodicity following the cardiac cycle was observed on the symptomatic side, and a sharp increase was observed if SS diverticulum was present. Shear stress was highest near the narrowest segments of the vessel. Pressure was observed to be lower on the symptomatic side at the transverse-SS junction for all 3 patients. CONCLUSION: Computational fluid dynamics modeling of blood flow through the CVOT in PST suggests that low pressure may be the cause of dehiscence, and tinnitus may result from periodic increases in TKE.

What should otolaryngologists know about dural venous sinus stenting?

Dural venous sinus stenting is an emerging and exciting area in otolaryngology in collaboration with neurosurgeons and neuroradiologists. The first cases were reported 20 years ago. It is now considered part of the routine treatment of increased intracranial pressure due to transverse sinus stenosis. ENT doctors are the first to see these patients in their clinics, as sinus headaches, pulsating tinnitus, and dizziness are the most common symptoms. Previously, with limited success, high-dose diuretics and intracranial shunts had been the only options for treating these patients. Other methods, such as covering the sigmoid sinuses with graft material, appear to cause a sudden increase in intracranial pressure that can lead to blindness and even death. This overview summarizes the clinical and imaging characteristics of patients who will benefit from endovascular sinus stenting for elevated intracranial pressure.

Endovascular stenting using a sagittal sinus approach for sigmoid sinus wall dehiscence related to intractable pulsatile tinnitus: a case series.

BACKGROUND: Sigmoid sinus wall dehiscence can lead to pulsatile tinnitus with a significant decrease in quality of life, occasionally leading to psychiatric disorders. Several surgical and endovascular procedures have been described for resolving dehiscence. Within endovascular procedures, the sagittal sinus approach could be a technical alternative for tracking and accurate stent positioning within the sigmoid sinus when the jugular bulb anatomy is unfavorable. CASE PRESENTATION: A retrospective case series of three patients with pulsatile tinnitus due to sigmoid sinus wall dehiscence without intracranial hypertension was reviewed from January 2018 to January 2022. From the participants enrolled, the median age was 50.3 years (range 43-63), with 67% self-identifying as female and 33% as male. They self-identified as Hispanic. Sigmoid sinus dehiscence was diagnosed using angiotomography, and contralateral transverse sinus stenosis was observed in all patients. Patients underwent surgery via a navigated endovascular sagittal sinus approach for sigmoid sinus stenting. No neurological complications were associated with the procedure. Pulsatile tinnitus improved after the procedure in all patients. CONCLUSIONS: Superior sagittal sinus resection for sigmoid sinus wall stenting is a safe and effective technique. Pulsatile tinnitus due to sigmoid sinus wall dehiscence could be treated using the endovascular resurfacing stenting technique. However, further research is needed to evaluate the potential benefit of contralateral stenting for removing sinus dehiscence when venous stenosis is detected. However, resurfacing sigmoid sinus wall dehiscence results in symptomatic improvement.

Anatomical Study of the Supratentorial Extension for the Retrolabyrinthine Presigmoid Approaches.

BACKGROUND: Supratentorial craniotomy represents the upper part of the combined trans-tentorial or the supra-infratentorial presigmoid approach. In this study, we provide qualitative and quantitative analyses for the supratentorial extension of the presigmoid retrolabyrinthine suprameatal approach (PRSA). METHODS: The infratentorial PRSA followed by the supratentorial extension craniotomy with dividing and removal of the tentorial strip were performed on both sides of 5 injected human cadaver heads (n = 10 sides). Quantitative analysis was performed for the surface area gained (surgical accessibility) by adding the supratentorial craniotomy. Qualitative analysis was performed for the parts of the brainstem, cranial nerves, and vascular structures that became accessible by adding the supratentorial craniotomy. The anatomical obstacles encountered in the added operative corridor were analyzed. RESULTS: The supratentorial extension of PRSA provides an increase in surgical accessibility of 102.65% as compared to the PRSA standalone. The mean surface area of the exposed brainstem is 197.98 (standard deviation: 76.222) and 401.209 (standard deviation: 123.96) for the infratentorial and the combined supra-infratentorial presigmoid approach, respectively. Exposure for parts of III, IV, and V cranial nerves is added after the extension, and the surface area of the outer craniotomy defect has increased by 60.32%. Parts of the basilar, anterior inferior cerebellar, and superior cerebellar arteries are accessible after the supratentorial extension. CONCLUSIONS: The supratentorial extension of PRSA allows access to the supra-trigeminal area of the pons and the lower part of the midbrain. Considering this surgical accessibility and exposure significantly assists in planning such complex approaches while targeting central skull base lesions.

Jugular Foramen Paragangliomas.

Paragangliomas are the most common tumors at jugular foramen and pose a great surgical challenge. Careful clinical history and physical examination must be performed to adequately evaluate neurological deficits and its chronologic evolution, also to delineate an overview of the patient performance status. Complete imaging evaluation including MRI and CT scans should be performed, and angiography is a must to depict tumor blood supply and sigmoid sinus/internal jugular vein patency. Screening for multifocal paragangliomas is advisable, with a whole-body imaging. Laboratory investigation of endocrine function of the tumor is necessary, and adrenergic tumors may be associated with synchronous lesions. Preoperative prepare with alpha-blockage is advisable in norepinephrine/epinephrine-secreting tumors; however, it is not advisable in exclusively dopamine-secreting neoplasms. Best surgical candidates are young otherwise healthy patients with smaller lesions; however, treatment should be individualized each case. Variations of infratemporal fossa approach are employed depending on extensions of the mass. Regarding facial nerve management, we avoid to expose or reroute it if there is preoperative function preservation and prefer to work around facial canal in way of a fallopian bridge technique. If there is preoperative facial nerve compromise, the mastoid segment of the nerve is exposed, and it may be grafted if invaded or just decompressed. A key point is to preserve the anteromedial wall of internal jugular vein if there is preoperative preservation of lower cranial nerves. Careful multilayer closure is essential to avoid at most cerebrospinal fluid leakage. Residual tumors may be reoperated if growing and presenting mass effect or be candidate for adjuvant stereotactic radiosurgery.

The Posterior Auricularis Muscle as Superficial Landmark for the Sigmoid Sinus and Transverse-Sigmoid Sinus Junction: An Anatomical Study.

OBJECTIVE: Neuronavigation systems coupled with previously reported external anatomical landmarks assist neurosurgeons during intracranial procedures. We aimed to verify whether the posterior auricularis muscle (PAM) could be used as an external landmark for identifying the sigmoid sinus (SS) and the transverse-sigmoid sinus junction (TSSJ) during posterior cranial fossa surgery. METHODS: The PAM was dissected in 10 adult cadaveric heads and after drilling the underlying bone, the relationships with the underlying SS and TSSJ were noted. The width and length of the PAM, and the distance between the muscle and reference points (asterion, mastoid tip, and midline), were measured. RESULTS: The PAM was identified in 18 sides (9 left, 9 right). The first 20 mm of the muscle length (mean 28.28 mm) consistently overlay the mastoid process anteriorly and the proximal half of the SS slightly posteriorly on all sides. The superior border was a mean of 2.22 mm inferior to the TSSJ and, especially when the muscle length exceeded 20 mm, this border extended closer to the transverse sinus; it was usually found at a mean of 3.11 mm (range 0.0-13.80 mm) inferior to the distal third of the transverse sinus. CONCLUSIONS: Superficial landmarks give surgeons improved surgical access, avoiding overexposure of deep neurovascular structures and reducing brain retraction. On the basis of our cadaveric study, the PAM is a reliable and accurate direct landmark for identifying the SS and TSSJ. The PAM could potentially be used for guiding the retrosigmoid approach.

Surgical Management of Pulsatile Tinnitus due to Sigmoid Sinus Diverticulum and Dehiscence - A Technical Note.

Pulsatile tinnitus (PT) is the perception of an auditory sensation without an external source and in synchrony with the heartbeat. One of the most common cases of PT is bony anomalies of the sigmoid sinus, including dehiscence or diverticula. This case report describes a 26-year-old female patient who presented with pulsatile tinnitus caused by sigmoid sinus diverticula and dehiscence, which was successfully treated with cortical mastoidectomy with diverticula closure using pedicled temporalis fascia and resurfacing of the dehiscence with autogenous bone pate along with bone cement. We recommend thorough clinical and radiological workup to rule out other possible causes of PT before surgical intervention. In addition, we would like to highlight the surgical technique using pedicled temporalis fascia that we have used in our patient, which is easily reproducible and offers successful outcomes.

Venous Sinus Thrombosis-Associated with Posterior Cranial Fossa Surgery. A Systematic Review and Meta-Analysis of Natural History, Risk Factors, Treatment, and Outcome.

BACKGROUND: Venous sinus thromboses (VSTs) are rare complications of neurosurgical procedures in the proximity of the dural sinuses. Surgery of the posterior cranial fossa (PCF) and particularly of the cerebellopontine angle (CPA) shows increased risk of VST. VST management is challenging because anticoagulant therapy must be balanced with the risk of postoperative bleeding. We performed a systematic review and meta-analysis to summarize the most important neuroradiologic and clinical aspects of VST after PCF/CPA surgery. METHODS: We performed a comprehensive literature search to identify articles reporting data on VST after PCF/CPA surgery. We selected only comparative studies providing adequate neuroimaging assessing VST and a control group. RESULTS: We included 13 articles reporting 1855 patients. VST occurred in 251/1855 cases (estimated incidence, 17.3%; 95% confidence interval [CI], 12.4%-22.2%). Only presigmoid approach (odds ratio [OR], 2.505; 95% CI, 1.161-5.404; P = 0.019) and intraoperative sinus injury (OR, 8.95; 95% CI, 3.43-23.34; P < 0.001) showed a significant association with VST. VST-related symptoms were reported in 12/251 patients with VST (pooled incidence, 3.1%; 95% CI, 1%-5.2%). In particular, we found a significantly increased OR of cerebrospinal fluid leak (OR, 3.197; 95% CI, 1.899-5.382; P < 0.001) and cerebrospinal fluid dynamic alterations in general (OR, 3.625; 95% CI, 2.370-5.543; P < 0.001). Indications for VST treatment were heterogeneous: 58/251 patients underwent antithrombotics, with 6 treatment-related bleedings. Recanalization overall occurred in 56.4% (95% CI, 40.6%-72.2%), with no significant difference between treated and untreated patients. However, untreated patients had a favorable outcome. CONCLUSIONS: VST is a relatively frequent complication after PCF/CPA surgery and a presigmoid approach and intraoperative sinus injury represent the most significant risk factors. However, the clinical course is generally benign, with no advantage of antithrombotic therapy.

Safety evaluation of sinus patency after stereotactic radiosurgery for transverse-sigmoid sinus dural arteriovenous fistulas: implications of treatment options for patients with Borden type I fistulas.

OBJECTIVE: This study aimed to assess the efficacy and safety of stereotactic radiosurgery (SRS) in treating transverse-sigmoid sinus dural arteriovenous fistulas (TSS DAVFs), and to investigate post-SRS sinus patency, focusing on the risk factors associated with treated sinus occlusion. METHODS: Data from 34 patients treated with SRS between January 2006 and April 2023 were analyzed. Detailed angioarchitecture was confirmed using digital subtraction angiography before SRS. Angiography of the ipsilateral internal carotid artery and vertebral artery was performed to evaluate whether the involved side of the TSS was used for normal venous drainage. TSS stenosis was defined as sinus diameter < 50% of the normal proximal diameter. DAVF shunt obliteration, TSS occlusion, neurological status, and adverse events were also evaluated. RESULTS: Of the 34 patients, 21 had Borden type I and 14 had Borden type II DAVFs. The median age at SRS was 64 years (interquartile range 54-71 years), and the follow-up period was 31 months (interquartile range 15-94 months). Complete shunt obliteration was achieved in 24 (70.6%) patients. The cumulative 2-, 3-, and 5-year shunt obliteration rates were 49.6%, 71.2%, and 86.0%, respectively. Borden type I had higher obliteration rates (60.5%, 83.1%, and 94.4%, respectively) than Borden type II (41.7%, 51.4%, and 75.7%, respectively; p = 0.034). TSS occlusion occurred in 5 patients (14.7%). The cumulative 1-, 5-, and 10-year TSS occlusion rates were 2.9%, 8.3%, and 23.6%, respectively, across the entire cohort. All occlusions occurred exclusively in the sinuses that were not used for normal venous drainage. Cox proportional analyses revealed that TSS stenosis and the sinus not being used for normal venous drainage were significantly associated with a greater risk of TSS occlusion after SRS (HR 9.44, 95% CI 1.01-77.13; p = 0.049). CONCLUSIONS: SRS is effective and safe for TSS DAVF and results in favorable shunt obliteration, symptom improvement, and low complication rates. TSS occlusion after SRS is asymptomatic and is limited to sinuses that are not used for normal venous drainage.

Fluid-structure interaction study on the causes of mending material damage after sigmoid sinus wall reconstruction.

BACKGROUND AND OBJECTIVE: Sigmoid Sinus (SS) Wall Reconstruction (SSWR) is the mainstream treatment for pulsatile tinnitus (PT), but it has a high risk of recurrence. The damage of mending material is the key cause of recurrence, and its hemodynamic mechanism is still unclear. The purpose of this study was to investigate the hemodynamic causes of mending material breakage. METHODS: In this study, six patient-specific geometric models were reconstructed based on the data of the computed tomography angiography (CTA). The transient fluid-structure coupling method was performed to clarify the hemodynamic state of sigmoid sinus and the biomechanical state of the mending material. The distribution of stress and displacement and the flow pattern were calculated to evaluate the hemodynamic and biomechanics difference at the mending material area. RESULTS: The area of blood flow impact in some patients (2/6) was consistent with the damaged location of the mending material. The average stress (6/6) and average displacement (6/6) of damaged mending material were higher than those of complete mending material. All (6/6) patients showed that the high-stress and high-displacement proportion of the DMM region was higher than that of the CMM region. Moreover, the average stress fluctuation (6/6) and average displacement (6/6) fluctuation degree of damaged mending material is larger than that of complete mending material. CONCLUSIONS: The impact of blood and the uneven stress and displacement fluctuation of the mending material may be the causes of mending material damage. High stress and high displacement might be the key causes of the mending material damage.

Evaluation of the Sigmoid Sinus Morphology by Cone Beam Computed Tomography; Touchstone of the Posterior Cranial Fossa.

OBJECTIVE: In this study, we aimed to analyze the relationship of the sigmoid sinus (SS) with the external auditory canal, facial nerve, and mastoid cells from an anatomic point of view, to define the position of the SS during transmastoid, translabyrinthine, retrosigmoid (lateral suboccipital) approaches, in tympanomastoidectomy and posterior cranial fossa surgery. METHODS: In this study, the morphologic structures associated with the sigmoid sinus were evaluated in cone beam computed tomography images taken between 2015 and 2022. The images of 68 men and 106 women, aged 18-65 years, obtained from the archive of Ankara University Faculty of Dentistry, Department of Oral and Maxillofacial Radiology were analyzed. RESULTS: The most common SS pattern was type II, with a rate of 60.8% (n = 209); the second was type III, with 20.6% (n = 71); and the least common was type I, with 18.6% (n = 64). Although the distance between the horizontal line passing through the external auditory canal and facial nerve and the anterior contour of the SS was highest in type I (right, 7.26 ± 1.62; left, 7.44 ± 0.97), it was lowest in type III (right, 4.40 ± 1.50; left, 4.84 ± 1.16) (P < 0.05). CONCLUSIONS: This study highlights the importance of the SS position in surgery, with special reference to otologic, neurotologic, and posterior cranial fossa surgery. To avoid intraoperative complications, each patient should be evaluated preoperatively by appropriate radiologic methods.

Severe bilateral papilledema after sigmoid sinus constriction surgery: a case report.

BACKGROUND: Papilledema is a common sign of various diseases in the eye. It could result from any conditions of increased intracranial pressure (ICP). Underlying the etiology of papilledema and appropriate treatment in time is essential. CASE REPORT: We present a case of severe bilateral papilledema after sigmoid sinus constriction surgery. A 25-year-old female presented with a 1-month history of bilateral blurred vision, headache, and vomiting. The patient had a history of right-side sigmoid sinus constriction surgery for pulsatile tinnitus (PT) one month before in another hospital. Fundus examination showed severe bilateral papilledema. Lumbar puncture showed an elevated cerebrospinal fluid (CSF) opening pressure of 29 cm H2O. Neuroimaging examination demonstrated the right sigmoid sinus filling defect as changes after surgery. We referred the patient to the initial surgeon, who repaired the sigmoid sinus on the right side by removing the implanted gelatin sponge, as diuretic treatment could not be effective. Intracranial hypertension symptoms and signs improved soon after eliminating sigmoid sinus stenosis. Neuroimaging showed resolved right sigmoid sinus stenosis after the second surgery. CSF opening pressure was 14.5 cm H2O at the 1-month follow-up. Fundus examination showed entirely resolved papilledema. Three years of follow-up showed no recurrence. CONCLUSIONS: This is the first clinical report of intracranial hypertension associated with sigmoid sinus constriction surgery. Although rare, rapid detection and adequate etiology management could lead to a good prognosis. It highlights the need for ophthalmologists to be aware of the diagnostic approach to papilledema and enhance cooperation with multidisciplinary departments. The most likely cause of the intracranial hypertension was dominant sinus surgical constriction by mechanical external compression, as confirmed by the complete clinical remission following the second operation to remove the implanted gelatin sponge. Thus, this case also highlights the importance of selecting the appropriate therapeutic option for PT. Surgical sinus constriction should no longer be considered a viable option for PT treatment.

Experience in the management of sigmoid sinus thrombophlebitis secondary to middle ear cholesteatoma.

OBJECTIVE: To discuss the management of sigmoid sinus thrombophlebitis secondary to middle ear cholesteatoma. METHODS: We retrospectively analyzed all cases of sigmoid sinus thrombophlebitis caused by middle ear cholesteatoma over a period of 7 years. 7 male and 2 female patients, ranging in age from 9 to 66 years, were diagnosed with sigmoid sinus thrombophlebitis by clinical presentation and radiological examination. By executing a modified mastoidectomy and tympanoplasty (canal wall-down tympanoplasty) to entirely remove the cholesteatoma-like mastoid epithelium, all patients were effectively treated surgically without opening the sigmoid sinus. All patients were treated with broad-spectrum antibiotics, but no anticoagulants were used. RESULTS: 9 patients had otogenic symptoms such as ear pus, tympanic membrane perforation, and hearing loss. In the initial stage of the surgery, modified mastoidectomy and tympanoplasty were performed on 8 of the 9 patients. 1 patient with a brain abscess underwent puncturing (drainage of the abscess) to relieve cranial pressure, and 4 months later, a modified mastoidectomy and tympanoplasty were carried out. Following surgery and medication, the clinical symptoms of every patient improved. After the follow-up of 6 months to 7 years, 3 patients were re-examined for MRV and showed partial sigmoid sinus recovery with recanalization. 4 months following middle ear surgery, the extent of a patient's brain abscess lesions was significantly reduced. 1 patient experienced facial paralysis after surgery and recovered in 3 months. None of the patients had a secondary illness, an infection, or an abscess in a distant organ. CONCLUSION: The key to a better prognosis is an adequate course of perioperative antibiotic medication coupled with surgical treatment. A stable sigmoid sinus thrombus can remain for a long time after middle ear lesions have been removed, and it is less likely to cause infection and abscesses in the distant organs. The restoration of middle ear ventilation is facilitated by tympanoplasty. It is important to work more closely with multidisciplinary teams such as neurology and neurosurgery when deciding whether to perform lateral sinusotomies to remove thrombus or whether to administer anticoagulation.

Intracranial Interdural and Extradural Cerebellar Convexity Dermoid Cyst: A Case Report of Rare Tumor at the Rarest Location.

Intracranial dermoid cysts are rare dysembryonic tumors of benign nature. These are uncommon in adults. If present, they are usually located in the midline or along the lines of embryonic fusion. The posterior fossa region is an infrequent site. Extradural or interdural locations are even more rare. In this case report, the authors report a laterally located large posterior fossa right cerebellar convexity interdural and extradural dermoid cyst over the sigmoid sinus. It was managed by totally extradural maximum possible safe decompression with microneurosurgical technique. The authors share their experience of addressing this rare pathology at the rarest location with unusual imaging findings.

Thrombosis of sigmoid sinus, transverse sinus, and internal jugular vein in chronic otitis media in 9-year-old girl: a case report.

Introduction and importance: Chronic otitis media can lead to dreadful intracranial complications, the most common being meningitis. A concomitant finding of thrombosis in more than one sinus with a cerebral vein is extremely rare. Septic sigmoid sinus thrombosis has an infectious origin and the treatment is debatable between antibiotics and surgery. Case presentation: A case of 9-year-old female with prolonged symptoms of right sided ear discharge, fever, right sided neck pain, and vomiting. Examination revealed tachycardia and neck rigidity suggesting meningitis. The child developed shock, generalized seizure, and a persistent high grade fever in the course of hospital stay. Brain imaging revealed sigmoid, transverse, and internal jugular thrombosis. Blood culture grew both gram-positive and gram-negative bacteria, suggesting the infectious origin of the thrombus. The authors treated meningitis with cephalosporin and vancomycin at first, and then additional antibiotics to treat the septic sigmoid sinus thrombosis. Clinical discussion: Sigmoid sinus thrombosis is a rare condition caused by infections, thrombophilia, head trauma, some types of cancer, and intravenous drug use. Cerebral vein or sinus thrombosis can lead to raised intracranial pressure and can cause fever, otalgia, headache, vomiting, cranial nerve palsies, papilledema altered mental status and may cause seizures, stupor, and coma. Prompt diagnosis by CT scan or MRI and prompt treatment with antibiotics are crucial. Conclusion: Sigmoid sinus thrombosis with involvement of the transverse sinus and internal jugular vein is a rare complication of chronic otitis media, and should be suspected if a recurring fever with features of raised intracranial pressure is present in a child with chronic otitis media.