Imaging Characteristics of Sigmoid Sinus Wall Anomalies, Idiopathic Intracranial Hypertension, and Spontaneous CSF Leaks

Sigmoid Sinus Wall Anomalies Can Progress and May Not Be Congenital

OBJECTIVE

Sigmoid sinus wall anomalies (SSWA) are closely linked to venous pulsatile tinnitus (PT). This study aims to demonstrate that SSWA develops progressively rather than being congenital.

METHODS

We retrospectively analyzed 42 PT patients with SSWA who had at least two non-operative CT scans at our clinic. CT images were longitudinally assessed to track SSWA progression, while MRI and Doppler ultrasound evaluated transverse sinus stenosis and venous hemodynamics. Changes in PT perception were tracked using the tinnitus handicap inventory (THI) questionnaire.

RESULTS

Among the 42 SSWA patients, 12 (28.6%) exhibited progression. Anastomosis between diploic vein and diverticulum was significantly higher compared to the dehiscence cohort (p < 0.01). Within the diverticulum group, seven individuals (30.4%) experienced enlargement, with a mean diverticular wall expansion of 5.9% ± 11.4%. Progressive erosion was observed in two cases (12.5%) in the dehiscence cohort, with a mean sigmoid plate erosion of 3.8% ± 10.1%. In cases progressing from dehiscence to diverticulum, three subjects transitioned, with a mean sigmoid sinus wall length expansion of 43.8% ± 31.9%. SSWA progression showed a significant negative correlation with QBILATERAL (r = -0.857, p = 0.014), and there was a significant difference between initial and revisit THI scores (p < 0.01).

CONCLUSION

SSWA can undergo morphological progression, indicating it is a progressive clinical condition rather than congenital.

LEVEL OF EVIDENCE

4 Laryngoscope, 2024.

Resurfacing Dehiscence(s) Without Reducing Diverticulum Effectively Silences Pulsatile Tinnitus: Novel Surgical Techniques for Diverticulum and Intraoperative Microphone Monitoring

OBJECTIVE

To emphasize the surgical importance of addressing dehiscence over diverticulum in resolving pulsatile tinnitus (PT) in patients with sigmoid sinus wall anomalies (SSWAs) and investigate anatomical differences.

STUDY DESIGN

Retrospective data analysis.

SETTING

Multi-institutional tertiary university medical centers.

PATIENTS

Fifty participants (dehiscence/diverticulum, 29:21 cases) with SSWA-associated PT were included in the study. All 21 diverticulum participants underwent surgical intervention.

INTERVENTIONS

1) Surgical intervention with novel techniques monitored by intraoperative microphone. 2) Radiologic and ophthalmologic imaging methods.

MAIN OUTCOME MEASURES

Quantitative and qualitative preoperative and postoperative alterations of PT and anatomical differences between dehiscence and diverticulum.

RESULTS

Addressing dehiscence overlying diverticulum and sigmoid sinus wall dehiscences significantly reduced visual analog score and Tinnitus Handicap Inventory ( p < 0.01). Sinus wall reconstruction led to substantial PT sound intensity reduction in the frequency range of 20 to 1000 Hz and 20 to 500 Hz (paired-sample t test, p < 0.01). Diploic vein analysis showed a significant positive correlation in 85.7% of the diverticulum cohort compared with the dehiscence cohort ( p < 0.01). Eight percent of the participants exhibited papilledema, which was limited to the dehiscence cohort.

CONCLUSION

1) Effective reduction of PT can be achieved by addressing all dehiscences, including those overlying the diverticulum, without the need to exclude the diverticulum. 2) Diploic vein may involve in the formation of diverticulum, and loss of dura mater and vascular wall thickness are observed at the SSWA locations.

Multiple skull base defects in the setting of spontaneous cerebrospinal fluid rhinorrhea; a dual institution view

PURPOSE

Idiopathic intracranial hypertension (IIH) is a condition of high cerebrospinal fluid (CSF) pressure that presents with CSF leak. The implications of multiple skull base defects (SBD) and associated synchronous CSF leaks have not been previously explored.

MATERIALS AND METHODS

A dual institutional case-control study examined multiple SBD's and encephaloceles on the risk of CSF leak and postoperative failures post-repair. IIH patients with CSF leaks and IIH controls without leaks were selected retrospectively. Chi square analysis evaluated for statistically significant alterations in probability with CSF leak development.

RESULTS

192 patients were selected with 108 IIH controls and 84 spontaneous CSF leak cases. Signs and symptoms for IIH controls and CSF leak cases respectively were pulsatile tinnitus (60.2 % and 29.8 %), headaches (96.3 % and 63.1 %), papilledema (74.1 % and 12.5 %), visual field defects (60.8 % and 13 %) (p < 0.001). Encephalocele formation in controls was 3.7 % compared to cases at 91.6 % (p < 0.001). Multiple SBD's in controls compared cases was 0.9 % and 46.4 % respectively (p < 0.001). Subgroup analysis of CSF leak cases showed 15 patients with two CSF leak repairs due to a recurrence. 27 (39.1 %) single leak cases had multiple SDB's while 12 (80 %) recurrent leaks had multiple SDB's (p = 0.004).

CONCLUSIONS

Patients with radiographic evidence of multiple SBD's and encephaloceles represent a high-risk population with a propensity for CSF leaks. Secondary SBD's are common in patients with spontaneous CSF rhinorrhea and higher in patients with a recurrence.

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.

Case report: Novel transtemporal transverse sinus decompression surgery to alleviate transverse sinus stenosis in a pulsatile tinnitus patient with restricted bilateral venous outflow

Transverse sinus (TS) stenosis is common in individuals with venous pulsatile tinnitus (PT). While PT can be addressed by endoluminal or extraluminal methods, the former has shown promise in alleviating symptoms associated with increased intracranial pressure. This study explores the potential of extraluminal methods to alleviate TS stenosis and eliminate PT caused by sigmoid sinus diverticulum. A 31-year-old male patient presenting with left-sided PT, attributed to a large, pedunculated sigmoid sinus diverticulum along with severe ipsilateral TS stenosis and contralateral TS hypoplasia, underwent ipsilateral extraluminal TS decompression surgery following sigmoid sinus wall reconstruction under local anesthesia. Postoperative CT and MR angiography revealed a significant increase in the TS lumen from 0.269 to 0.42 cm2 (56.02%) 2 years after surgery. Cervical Doppler ultrasound demonstrated a 36.07% increase in ipsilateral outflow volume to 16.6 g/s and a 77.63% increase in contralateral outflow volume to 1.35 g/s. In conclusion, this pioneering study showcases the potential of transtemporal TS decompression surgery in creating space for adaptive expansion of the TS lumen. However, the procedure should be reserved for individuals with severely compromised venous return.

Intracranial pressure, lateral sinus patency, and jugular ultrasound hemodynamics in patients with venous pulsatile tinnitus

The clinical and hemodynamic characteristics of venous pulsatile tinnitus (PT) patients with normal or elevated cerebrospinal fluid pressure (CSFP) have not been clearly differentiated. This study aimed to explore CSFP among patients with PT as the solitary symptom, as well as quantitatively and qualitatively assess the role of the degree of transverse sinus (TS) stenosis and jugular hemodynamics in venous PT patients. A total of 50 subjects with venous PT with or without sigmoid sinus wall anomalies (SSWAs) were enrolled in this study. In addition to radiologic assessments for TS stenosis and invagination of arachnoid granulation (AG) in TS, CSFP and jugular hemodynamics were measured via cerebrospinal fluid (CSF) manometry and Doppler ultrasound. Apart from group comparisons and correlation analyses, multivariate linear regression, and receiver operating characteristic (ROC) models were used to identify the sensitivity and specificity of the index of transverse sinus stenosis (ITSS) and hemodynamic variables with inferential significance. The mean CSFP of all cases was 199.5 ± 52.7 mmH2O, with no statistical difference in CSFP between the diverticulum and dehiscence groups. Multivariate linear regression analysis demonstrated that CSFP was linearly correlated with ITSS and pulsatility index (PI). ROC analysis showed that the area under the ROC curve of PI was 0.693 at 200 mmH2O threshold, and the best PI cut-off value was 0.467, with a sensitivity of 65.7% and specificity of 81.8%. For 250 mmH2O threshold, the area under the ROC curve of PI was 0.718, and the best PI cut-off value was 0.467 with a sensitivity of 68.4% and specificity of 75.0%. Additionally, the area under the ROC curve of ITSS was 0.757, and the best ITSS cutoff value was 8.5 (p = 0.002, 95% CI = 0.616–0.898) with a sensitivity of 72.4% and specificity of 75.0% at 200 mmH2O threshold. In conclusion, patients with venous PT as the only presenting symptom should be suspected of having borderline or increased CSFP when they present with high ITSS, BMI and low PI. Further, AG in TS without encephalocele and empty sellae are not limiting findings for differentiating the level of CSFP in patients with venous PT.

Evidence of air-conduction transmission pathway and strategized transtemporal operative techniques for venous pulsatile tinnitus: Combining water occlusion test and operative sensing applications

OBJECTIVES

(1) To establish evidence of the transmission pathway of venous pulsatile tinnitus (PT) associated with sigmoid sinus wall anomalies (SSWAs) and (2) quantify the efficacy of transtemporal surgery.

METHODS

This retrospective study included 33 surgical cases of PT associated with SSWAs and 15 controls with venous PT without SSWAs. Quantitative water occlusion test (q-WOT) and imaging data were acquired for preoperative evaluation prior to strategized transtemporal osteovascular reconstruction surgery. A condenser microphone and hydrophone were intraoperatively deployed to assess and monitor in vivo amplitude variations of the PT in eight participants.

RESULTS

A total of 23 (69.6%) participants with SSWA responded to the q-WOT with a median solution volume of 1.3 (1.1/1.6), which significantly differed from that observed in controls (p < 0.01). The change in the operative peak amplitude of the acoustic data was statistically significant (p < 0.01), from a median of 57.6 (55.5/57.9) dB SPL to 34.3 (33.4/38.8) dB SPL.

CONCLUSION

Intraoperative application of acoustic sensors revealed that PT associated with SSWAs is predominantly transmitted via the air-conduction pathway. If objective findings such as q-WOT and sensing applications suggest that the transmission of venous PT is involved in middle ear air conduction, the reconstruction technique should be prioritized; if less involvement of middle ear air-conduction is indicated, addressing flow pathologies may be imperative for resolving venous PT.

LEVEL OF EVIDENCE

4.