Investigation of serum calcium and vitamin D levels in superior semicircular canal dehiscence syndrome: A case control study

Objective: It remains unknown whether calcium metabolism has any effect on the clinical presentation of superior semicircular canal dehiscence(SSCD). Our aim was to analyse the adjusted calcium and vitamin D levels in SSCD patients compared to a control group.Methods: This was a prospective case-control study performed in a tertiary referral center, university teaching hospital in the UK. It included all new patients with SSCD seen in a dedicated skull base clinic over a 5-year period(2015-2019) compared to a gender and age matched control group. The main outcome of the study was adjusted calcium and Vitamin D levels between the two groups.Results: A total of 31 SSCD patients were recruited with a matched number of control patients. The mean Vitamin D level on the SSCD group was 44.8 nmoL/l(SD: 20.8) compared to 47.5 nmoL/l(SD: 27.4) on the control group(p = 0.702). Mean Adjusted calcium level was 2.34 mmoL/l(SD: 0.7) for SSCD compared to2.41 mmoL/l(SD: 0.11) for controls(p = 0.01), being within normal limits for both the SSCD and the control group.Conclusion: Our study did not identify a link between Vitamin D levels and presence of SSCD. Normal adjusted calcium values were found in both groups. Despite that a statistically significant lower calcium level was found in the SSCD group which could indicate that suboptimal levels of calcium may affect the micro-environment of the otic capsule at the SSC region.

An evidenced-based diagnostic tool for superior semicircular canal dehiscence syndrome

Purpose:To construct a symptoms-based prediction tool to assess the likelihood of superior canal dehiscence(SSCD)on high-resolution CT.Materials and methods:Mathematical modeling was employed to predict radiologic evidence of SSCD at a tertiary neurotology referral center.Results:A total of 168 patients were included,of which 118 had imaging-confirmed SSCD.On univariate analysis significant predictors of SSCD presence were:sound/pressure-induced vertigo(p?0.006),disequilibrium(p?0.008),hyperacusis(p?0.008),and autophony(p?0.034).Multivariate analysis enabled a 14-point symptom-weighted tool to be developed,wherein a score of6 raised the suspicion of SSCD(70%likelihood of being present),R2?0.853.Conclusions:The likelihood of SSCD on CT scan can be determined with a high degree of certainty based on symptoms recorded at presentation.Using the evidenced-based diagnostic tool validated herein,a score6 with any symptom combination justifies ordering a CT scan.

Bilateral Superior Semicircular Canal Dehiscence without Signs of Vestibular Involvement about a Case

Superior semicircular canal dehiscence (SSCD) is a rare entity recently described whose typical clinical symptomatology is represented by dizziness triggered by a variation of pressure. We reported a case of SSCD which was diagnosed thanks to computed tomography (CT) scan of the petrous bone conducted systematically in front of mixed deafness with normal eardrum. The SSCD was bilateral and was revealed by mixed deafness on the left side and perception deafness on the right with a normal eardrum without the notion of vertigo. The cervical vestibular evoked myogenic potential (cVEMP) and an ultra-high resolution CT scan of the petrous bones in coronal and sagittal sections allowed the diagnosis. The SSCD should be considered in the presence of any conductive or mixed hearing loss with a normal eardrum. The CT scan in coronal and sagittal submillimetric sections allows the diagnosis.

Subtemporal Extradural Approach for Dehiscence of the Superior Semicircular Canal: Surgical Technique and Results in Three Consecutive Patients

We describe three patients with severe disabling symptoms of unilateral dehiscence of the superior semicircular canal (DSSC) who had surgical treatment. Each patient underwent a unilateral subtemporal extradural approach with resurfacing the DCCS. In all 3 patients, all symptoms were completely resolved and remained symptom free on the long term. There were no postoperative complications. Only one patient experienced a temporary CSF hypotension syndrome and some dizziness. The pseudo-conductive hearing loss improved or resolved in all patients. Surgical treatment should be considered in patients with severe, disabling DSSC symptoms. Surgical resurfacing of the DSSC is a safe and rewarding surgical technique. The long term success rate regarding the elimination of the pseudo-conductive hearing loss and resolution of vestibular symptoms outweigh the potential surgical risks of this technique in these patients.

Transmastoid Approach for Resurfacing the Superior Semicircular Canal Dehiscence with a Dumpling Structure

Background： Superior semicircular canal dehiscence （SSCD） is gradually recognized by otologists in recent years. The patients with SSCD have a syndrome comprising a series of vestibular symptoms and hearing function disorders which can be cured by the operation. In this study, we evaluated the characteristics of patients with SSCD and determined the effectiveness of treating this syndrome by resurfacing the canal via the transmastoid approach using a dumpling structure. Methods： Patients with SSCD, confirmed by high-resolution computed tomography and hospitalized at Beijing Tongren Hospital between November 2009 and October 2012, were included in the study. All of the patients underwent the unilateral transmastoid approach for resurfacing the canal, and received regular follow-up after surgery. Data from preoperative medical records and postoperative follow-up were comparatively analyzed to evaluate the effect of surgery. Results： In total, 10 patients and 13 ears （three left ears, four right ears, three bilateral ears） were evaluated in the study, which included 7 men and 3 women. Different symptoms and distinctive manifestations of vestibular evoked myogenic potential were found in these patients. Alter surgery, 4 patients had complete resolution, 5 had partial resolution, and 1 patient, with bilateral SSCD, had aggravation. None of the patients suffered from serious complications such as sensorineural hearing loss, facial paralysis, cerebrospinal fluid leakage, or intracranial hypertension. Conclusions： In patients with unilateral SSCD, resurfacing the canal via the transmastoid approach using a dumpling structure is an effective and sate technique. However, more consideration is needed for patients with bilateral SSCD.