Characteristics of Wax Occlusion in the Surgical Repair of Superior Canal Dehiscence in Human Temporal Bone Specimens

Occlusion of the Lateral Semicircular Canal, Endolymphatic Sac Surgery, and Cochlear Implantation: A Low Destructive Treatment for Unilateral Ménière's Disease and Deafness

INTRODUCTION

Surgical treatment of Ménière's disease (MD) and deafness aims to treat vertigo and hearing disabilities. Current treatment options like labyrinthectomy and cochlear implantation (CI) have shown acceptable results but are destructive. Less destructive procedures, like the occlusion of the lateral semicircular canal and endolymphatic sac surgery, have been shown to be successful in vertigo control. The combination of both procedures with CI has not been investigated; therefore the objective of this study was to investigate the outcome of this combination in patients with single-sided MD and moderately severe to complete sensorineural hearing loss.

METHODS

In this retrospective study, 10 patients with single-sided MD and moderately severe to complete sensorineural hearing loss were included. In all of them, a single-staged surgery, which consisted of CI, endolymphatic sac surgery, and occlusion of the lateral semicircular canal, was performed. The surgery was performed after a failed conservative therapy trial. The clinical outcome was evaluated by the Dizziness Handicap Inventory (DHI) and audiological tests. These were assessed preoperatively, 3 and 6 months after surgery. An MRI with a hydrops sequence was performed to support the clinical diagnosis.

RESULTS

After the combined surgery, the mean DHI testing improved significantly from 71 to 30. Mean audiological monosyllabic speech testing outcome with the cochlea implant was 65% at 65 dB. The residual hearing of 2 patients could be preserved after the surgical procedure.

CONCLUSION

The combination of occlusion of the lateral semicircular canal, endolymphatic sac surgery, and CI is an efficient low traumatic treatment for patients with a single-sided MD and moderately severe to complete sensorineural hearing loss.

Triple Semi-Circular Canal Occlusion and Cochlear Implantation: A Treatment Option for Single-Sided Menière's Disease with Functional Deafness-A Case Series

The surgical options for patients with single-sided Menière's disease and functional deafness are challenging. Our case series reports the outcomes of surgical treatments of patients with single-sided Menière's disease and functional deafness. These patients have undergone a one-staged occlusion of all semi-circular canals and cochlear implantation. Five patients (four female and one male; 62 ± 8.2 years with a range from 50 to 72 years) with single-sided Menière's disease and functional deafness were included in this study. In all cases, the patients suffered from frequent rotational vertigo episodes for many years. Other treatment options (e.g., medication) had not yet been successful. Preoperatively, the Dizziness Handicap Inventory (DHI) of all patients indicated severe emotional, physical, and functional deficits. Patients showed a functional (near-total) deafness of the affected ear in all cases. All patients were supplied with cochlear implants in combination with a triple occlusion of all semi-circular canals in a one-stage procedure. After a short period of increased dizziness following surgery and after the activation of the cochlear implant and CI rehabilitation (auditory-verbal therapy), vertigo control and an adequate audiological outcome were achieved. The DHI showed a constant decrease after surgery. The combination of a triple semi-circular canal occlusion and cochlear implantation can be an efficient treatment for patients with single-sided Menière's disease.

Transmastoid Occlusion Surgery for Superior Semicircular Canal Dehiscence Syndrome Improves Patient-Reported Quality-of-Life Measures and corrects cVEMP Thresholds and Amplitudes

OBJECTIVE

To determine the pre- and postoperative clinical, audiological, vestibular, and patient-reported measures in patients undergoing transmastoid occlusion surgery for superior canal dehiscence syndrome (SCDS).

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral centre, UK.

PATIENTS

All primary transmastoid occlusion surgeries for SCDS were included (tertiary centre, single-surgeon), January 2008 to July 2019.

INTERVENTIONS

Transmastoid superior canal occlusion surgery for SCDS.

MAIN OUTCOME MEASURES

We collated audiological (pure tone audiogram), vestibular (cervical vestibular evoked myogenic potentials [cVEMPs]), and patient-reported outcome measures (Dizziness Handicap Inventory and subjective symptom grading).

RESULTS

Fifty-two patients (55 ears) met the inclusion criteria. Thirty-one (56%) were female. Mean age was 47 years (range 29-63) and mean follow-up of 11.2 months. Six patients had bilateral disease, four of whom underwent sequential, bilateral surgery.Autophony was the most frequent presenting symptom, improving in 92%.Significant improvements were self-reported in patients' autophony (p < 0.0001), pressure- and noise-induced dizziness (p < 0.0001 and p < 0.0001), aural fullness (p = 0.0159), pulsatile tinnitus (p < 0.0001), perceived hearing loss (p = 0.0058), and imbalance (p = 0.0303).Overall Dizziness Handicap Inventory scores reduced from 45.9 to 27.4 (p < 0.0001), and across all subgroups of functional (p = 0.0003), emotional (p < 0.0001), and physical handicap (p = 0.0005).A 6.4-dB HL improvement in the air-bone gap (500-1000 Hz) occurred (95% confidence intervals 3.3-9.4 dB HL, p < 0.0001). There were no dead ears. cVEMP thresholds, when recordable, normalized in all except two ears.

CONCLUSIONS

Transmastoid occlusion is effective at improving patient-reported outcomes and normalizing cVEMP thresholds, though some symptoms, notably disequilibrium, persist to a variable degree.

Topical hemostatic agents in neurosurgery, a comprehensive review: 15 years update

Hemostasis in neurosurgery is of utmost importance. Bleeding management is one of the crucial steps of each neurosurgical procedure. Several strategies, namely thermal, mechanical, electric, and chemical, have been advocated to face blood loss within the surgical field. Over time, countless hemostatic agents and devices have been proposed. Furthermore, the ever-growing recent technological innovation has made available several novel and interesting tools. Pursuant to their impact on surgical practice, we perceived the imperative to update our previous disclosure paper. Therefore, we reviewed the literature and analyzed technical data sheets of each product in order to provide an updated and comprehensive overview in regard to chemical properties, mechanisms of action, use, complications, tricks, and pitfalls of topical hemostatic agents.

Current Trends, Controversies, and Future Directions in the Evaluation and Management of Superior Canal Dehiscence Syndrome

Patients with superior canal dehiscence syndrome (SCDS) can present with a range of auditory and/or vestibular signs and symptoms that are associated with a bony defect of the superior semicircular canal (SSC). Over the past two decades, advances in diagnostic techniques have raised the awareness of SCDS and treatment approaches have been refined to improve patient outcomes. However, a number of challenges remain. First, there is currently no standardized clinical testing algorithm for quantifying the effects of superior canal dehiscence (SCD). SCDS mimics a number of common otologic disorders and established metrics such as supranormal bone conduction thresholds and vestibular evoked myogenic potential (VEMP) measurements; although useful in certain cases, have diagnostic limitations. Second, while high-resolution computed tomography (CT) is the gold standard for the detection of SCD, a bony defect does not always result in signs and symptoms. Third, even when SCD repair is indicated, there is a lack of consensus about nomenclature to describe the SCD, ideal surgical approach, specific repair techniques, and type of materials used. Finally, there is no established algorithm in evaluation of SCDS patients who fail primary repair and may be candidates for revision surgery. Herein, we will discuss both contemporary and emerging diagnostic approaches for patients with SCDS and highlight challenges and controversies in the management of this unique patient cohort.

Interpositional arthroplasty of post-traumatic temporomandibular joint ankylosis: A modified method

The purpose of this study was to evaluate a modified method of interpositional arthroplasty for post-traumatic temporomandibular joint ankylosis. All patients were treated with a modified interpositional arthroplasty that included: navigation-assisted accurate bone dissection with minimal removal of only 5 mm of the ankylosed bony mass, novel application of bone wax and porcine acellular dermal matrix to prevent re-ankylosis, and a unique 3D-printed splint for occlusal stabilization and gap maintaining. The pre- and post-operative physical and radiological examinations of patients were recorded during routine follow-up visits. Postoperative follow-up visits lasted at least 12 months. Twelve patients, seven males and five females, ranging from 21 years to 59 years, were enrolled in this retrospective case series. All of the twelve patients with eighteen bony ankylosed temporomandibular joints were treated by our new method. The post-operative follow-up periods ranged from 1 year to 4 years. During the follow-up visits within at least 1 year, no one manifested re-ankylosis. The mean maximum incisor opening changed from 7.4 ± 5.3 mm (p < 0.001, before surgery) to 37.6 ± 3.9 mm (p < 0.001, last follow-up visit). No sign of post-operative infection or foreign body rejection was observed during the follow-up visits. The post-operative occlusal relationship was sound and stable. It is suggested that the modified method of interpositional arthroplasty provides favorable clinical and radiographic outcomes after a short-term follow up.

Stenting the Superior Petrosal Sinus in a Patient With Symptomatic Superior Semicircular Canal Dehiscence

Patients presenting superior semicircular canal dehiscence (SSCD) can experience symptoms such as conductive hearing loss, pulsatile tinnitus, autophony, and pressure-induced vertigo. Decreased cervical vestibular-evoked myogenic potentials (cVEMPs) thresholds and high-resolution computed tomography (HRCT) of the petrous bone are essential for diagnosis of SSCD syndrome. We report the case of a 43-year-old man suffering from constant right pulsatile tinnitus, intermittent autophony, and unsteadiness induced by physical exercise. An SSCD by the superior petrosal sinus (SPS) was confirmed on the right side by axial HRCT of the temporal bone reformatted in the plane of Pöschl and ipsilateral abnormally low elicited cVEMPs. Treatment options were discussed with the patient since the pulsatile tinnitus progressively became debilitating. Two options were considered: surgery or a new endovascular treatment; the patient chose the latter option. After stenting the right SPS, the intensity of the pulsatile tinnitus dramatically decreased. As there was no complication the patient was discharged at Day 1. The other symptoms improved progressively. By the 60-day follow-up visit the patient only reported a slight tinnitus worsened by physical exercise. Angiographic follow-up at 5 months confirmed the patency of the SPS. Stenting the SPS in patients with SSCD by the SPS appears to be an alternative to the existing surgical treatments.

Superior Canal Dehiscence Syndrome: Lessons from the First 20 Years

Superior semicircular canal dehiscence syndrome was first reported by Lloyd Minor and colleagues in 1998. Patients with a dehiscence in the bone overlying the superior semicircular canal experience symptoms of pressure or sound-induced vertigo, bone conduction hyperacusis, and pulsatile tinnitus. The initial series of patients were diagnosed based on common symptoms, a physical examination finding of eye movements in the plane of the superior semicircular canal when ear canal pressure or loud tones were applied to the ear, and high-resolution computed tomography imaging demonstrating a dehiscence in the bone over the superior semicircular canal. Research productivity directed at understanding better methods for diagnosing and treating this condition has substantially increased over the last two decades. We now have a sound understanding of the pathophysiology of third mobile window syndromes, higher resolution imaging protocols, and several sensitive and specific diagnostic tests. Furthermore, we have a treatment (surgical occlusion of the superior semicircular canal) that has demonstrated efficacy. This review will highlight some of the fundamental insights gained in SCDS, propose diagnostic criteria, and discuss future research directions.

Superior Semicircular Canal Dehiscence Syndrome - Diagnosis and Surgical Management

Introduction Superior semicircular canal dehiscence syndrome was described by Minor et al in 1998. It is a troublesome syndrome that results in vertigo and oscillopsia induced by loud sounds or changes in the pressure of the external auditory canal or middle ear. Patients may present with autophony, hyperacusis, pulsatile tinnitus and hearing loss. When symptoms are mild, they are usually managed conservatively, but surgical intervention may be needed for patients with debilitating symptoms.

Objective The aim of this manuscript is to review the different surgical techniques used to repair the superior semicircular canal dehiscence.

Data Sources PubMed and Ovid-SP databases.

Data Synthesis The different approaches are described and discussed, as well as their limitations. We also review the advantages and disadvantages of the plugging, capping and resurfacing techniques to repair the dehiscence.

Conclusions Each of the surgical approaches has advantages and disadvantages. The middle fossa approach gives a better view of the dehiscence, but comes with a higher morbidity than the transmastoid approach. Endoscopic assistance may be advantageous during the middle cranial fossa approach for better visualization. The plugging and capping techniques are associated with higher success rates than resurfacing, with no added risk of hearing loss.

Endoscopic-Assisted Repair of Superior Canal Dehiscence

Superior canal dehiscence (SCD) is a bony defect of the superior canal that can cause vestibular and/or auditory symptoms. Surgical repair of SCD provides effective relief from symptoms, and the middle fossa craniotomy approach with binocular microscopy offers direct visualization and surgical access to the arcuate eminence. However, for SCDs located along the downsloping tegmen medial to the peak of the arcuate eminence, a direct light of sight may be obscured, rendering visualization with traditional microscopy difficult. The endoscope is the ideal adjunct in middle fossa craniotomy approach SCD surgery and offers a safe, effective means to identify and repair arcuate eminence defects hidden from microscopic view.

Migration of Bone Wax into the Sigmoid Sinus after Posterior Fossa Surgery

BACKGROUND AND PURPOSE

Bone wax is a hemostatic agent that has been reported in some instances to migrate into the sigmoid sinus following posterior fossa surgery. The purpose of this study was to characterize the CT and MR imaging findings of this entity.

MATERIALS AND METHODS

The study included 212 consecutive patients who underwent posterior fossa surgery and postoperative CT and contrast-enhanced MR imaging. The presence of sigmoid sinus bone wax migration was determined with the following criteria: sigmoid sinus filling defect showing low signal on all MR imaging pulse sequences; sigmoid sinus filling defect showing low CT attenuation, similar to fat attenuation; and clinical confirmation that bone wax was used intraoperatively. CT and MR imaging of an in vitro bone wax sample was also performed.

RESULTS

We identified 6 cases of sigmoid sinus bone wax migration. In each case, a low-signal-intensity, low-attenuation filling defect was noted in the sigmoid sinus. The morphology was linear (n = 3) or globular (n = 3). In patients with serial imaging, the appearance of migrated bone wax remained stable over time. No adverse outcomes related to sigmoid sinus bone wax migration were encountered. In vitro imaging of bone wax confirmed low CT attenuation and low MR imaging signal intensity on T1WI and T2WI.

CONCLUSIONS

Bone wax migration into the sigmoid sinus is a recognizable imaging finding after posterior fossa surgery that appears to have a benign clinical course. The finding should be distinguished from more serious complications, such as venous sinus thrombosis.