The crystalline pattern of calcium in different topographical regions of the otoconial membrane. An electron probe and spectroscopic diffraction study

Low Bone Mineral Density and the Risk of Benign Paroxysmal Positional Vertigo

OBJECTIVE

This study aimed to comprehensively analyze the relationship between low bone mineral density (BMD) and the risk of benign paroxysmal positional vertigo (BPPV) based on the large prospective population-based UK Biobank (UKB) cohort.

STUDY DESIGN

Prospective population-based cohort study.

SETTING

The UKB.

METHODS

This prospective cohort study included UKB participants recruited between 2006 and 2010 who had information on BMD and did not have BPPV before being diagnosed with low BMD. Univariable and multivariable logistic regression models were constructed to assess the association between low BMD (overall low BMD, osteopenia, and osteoporosis) and BPPV. We further conducted sex and age subgroup analysis, respectively. Finally, the effects of antiosteoporosis and female sex hormone medications on BPPV in participants with osteoporosis were evaluated.

RESULTS

In total, 484,303 participants were included in the final analysis, and 985 developed BPPV after a maximum follow-up period of 15 years. Osteoporosis was associated with a higher risk of BPPV (odds ratio [OR] = 1.37, P = .0094), whereas osteopenia was not. Subgroup analyses suggested that the association between osteoporosis and BPPV was significant only in elderly females (≥60 years, OR = 1.51, P = .0007). However, no association was observed between antiosteoporosis or female sex hormone medications and BPPV in the participants with osteoporosis.

CONCLUSION

Osteoporosis was associated with a higher risk of developing general BPPV, especially in females aged ≥ 60 years old, whereas osteopenia was not associated with BPPV.

Effects of Neurological Disorders on Bone Health

Neurological diseases, particularly in the context of aging, have serious impacts on quality of life and can negatively affect bone health. The brain-bone axis is critically important for skeletal metabolism, sensory innervation, and endocrine cross-talk between these organs. This review discusses current evidence for the cellular and molecular mechanisms by which various neurological disease categories, including autoimmune, developmental, dementia-related, movement, neuromuscular, stroke, trauma, and psychological, impart changes in bone homeostasis and mass, as well as fracture risk. Likewise, how bone may affect neurological function is discussed. Gaining a better understanding of brain-bone interactions, particularly in patients with underlying neurological disorders, may lead to development of novel therapies and discovery of shared risk factors, as well as highlight the need for broad, whole-health clinical approaches toward treatment.

Risk Factors for the Recurrence of Benign Paroxysmal Positional Vertigo: A Systematic Review and Meta-Analysis

OBJECTIVE

Benign paroxysmal positional vertigo (BPPV) has a high recurrence rate, but the risk factor-associated recurrence are elusive.

METHODS

Searches were performed in PubMed, Embase, Cochrane library, Web of science, Chinese National Knowledge Infrastructure, and Sino Med up to November 3, 2019. The effect size was analyzed by odds ratio and 95% CI. Data from eligible studies were meta-analyzed using Stata version 15.0.

RESULTS

Our search resulted in a total of 4076 hits. Twenty-four outcomes of sixty articles were included in the meta-analysis. Risk factors for the recurrence of BPPV included female gender, age (≥65years), hyperlipidemia, diabetes, hypertension, migraine, cervical spondylosis, osteopenia/osteoporosis, head trauma, otitis media, abnormal vestibular evoked myogenic potential, and long use of computers. No significant differences were found in side, type of the involved semicircular canals, smoking, alcohol consumption, stroke, ear surgery, duration of vertigo before treatment, the times of repositioning, Meniere disease, sleep disorders, hypercholesterolemia, and 25-hydroxy vitamin D.

CONCLUSION

These findings strengthen clinical awareness of early warning to identify patients with potential relapse risk of BPPV and clinicians should counsel patients regarding the importance of follow-up after diagnosis of BPPV.

Can Osteopenia Induce Residual Dizziness After Treatment of Benign Paroxysmal Positional Vertigo?

OBJECTIVE

This study aimed to determine whether there is an association between osteopenia and residual dizziness after successful treatment of benign paroxysmal positional vertigo (BPPV).

METHODS

In all, 62 patients with canalolithiasis-type BPPV were included in the study. Patients were divided into two groups according to the presence of residual dizziness after resolution of BPPV. Univariate and multivariate analyses were performed to determine the factors associated with residual dizziness. Patients were analyzed based on age, sex, affected semicircular canal, affected side, BPPV duration, and presence of hypertension, diabetes mellitus, hyperlipidemia, and osteopenia.

RESULTS

In univariate analysis, BPPV duration and osteopenia showed a relatively significant association (p < 0.20) with the development of residual dizziness. On subsequent multivariate analysis using these factors, osteopenia remained a statistically significant factor in association with residual dizziness (p = 0.012, odds ratio, 9.916).

CONCLUSION

Osteopenia is associated with the development of residual dizziness. BPPV patients with osteopenia more frequently suffer from residual dizziness after successful treatment of BPPV than those without osteopenia.

Calcium Homeostasis During Attack and Remission in Patients With Idiopathic Benign Paroxysmal Positional Vertigo

OBJECTIVE

To evaluate changes in calcium metabolism in patients with idiopathic benign paroxysmal positional vertigo (BPPV) on initial presentation and at the follow-up visit.

SUBJECTS AND METHODS

The study comprised a total of 31 patients aged greater than 18 years who presented at the otorhinolaryngology outpatient clinic of our hospital, newly diagnosed as idiopathic BPPV based on the history compatible with BPPV and positive provocative maneuver (either Dix-Hallpike or Roll test). The first blood sample was obtained on the day of initial presentation when the patient was found to have active unilateral BPPV. After 6 months, a blood sample was again drawn in accordance with the procedure. Blood samples were analyzed for data on 25-hydroxyvitamin D (25(OH)-D), total calcium, parathormone and ionized calcium on initial presentation, and at the follow-up visit.

RESULTS

The patients comprised 20 (64.5%) women and 11 (35.5%) men with a mean age of 49.78 years (range, 23-75 years). During an attack a higher prevalence of decreased serum Vitamin D is less than 20 ng/ml, was determined (93.5% versus 38.7%). There were statistical differences between the Vitamin D values, parathormone, and corrected by pH ionized calcium in both periods (p < 0.05).

CONCLUSION

A statistically significant association was determined between Vitamin D and calcium metabolism in patients with idiopathic BPPV. It can be considered that Vitamin D deficiency and decreased ionized Ca level may be a risk for BPPV, not only in patients with osteoporosis but also in all patients. Very low levels of 25(OH)-D seem to be associated with recurrence of BPPV. The recurrences might possibly be prevented with supplementary Vitamin D especially in those with recurrent idiopathic BPPV but further studies would be necessary to determine this.

Osteoporosis as a risk factor for the recurrence of benign paroxysmal positional vertigo

OBJECTIVES/HYPOTHESIS

Benign paroxysmal positional vertigo (BPPV) frequently occurs in females over 50 years old, suggesting that a postmenopausal decrease in estrogen secretion might be involved in its onset. An estrogen deficiency is generally known to cause osteoporosis through a reduction in bone mass. This study was designed to investigate a clinical association between idiopathic BPPV and osteoporosis.

STUDY DESIGN

Case-control study.

METHODS

We measured the bone mineral density (BMD) at the lumbar vertebrae in 61 patients with idiopathic BPPV who were postmenopausal women over 50 years old using dual-energy x-ray absorptiometry. After being treated with the canalith repositioning maneuver, the patients were followed up for at least 1 year.

RESULTS

Our results showed that the incidence of osteoporosis in patients with BPPV was 26.2%, which was similar to those observed in epidemiological surveys conducted in Japan. However, we found that in BPPV patients with osteoporosis, the incidence of recurrence was 56.3%, which was significantly higher than that observed in patients with normal bone mineral density (16.1%). Furthermore, the frequency of BPPV recurrence increased as BMD decreased.

CONCLUSIONS

These results suggest that osteoporosis is a risk factor for BPPV recurrence. The prognosis of BPPV might be clinically predicted by BMD reduction.

Meniere's disease in the elderly

Menière disease usually begins in adults from 20 to 60 years old, and occurs in more than 10% of patients older than 65. The treatment of Menière disease in the elderly represents a challenge because of polymedication. Antivertiginous drugs such as betahistine and cinnarizin give good results with minor secondary effects. In contrast, major vestibular suppressor drugs such as thiethylperazin must be avoided as long-term treatment because of their side effects. Definitive vestibular surgical deafferentations such as labyrinthectomy and selective vestibular neurectomy represent optional procedures but must be carefully evaluated from case to case. Ablative procedures remain the efficient treatment of drop attacks, which represent a high potential risk of severe injuries by older patients sometimes with important social consequences.

Ultrastructural changes in otoconia of osteoporotic rats

The etiology of benign paroxysmal positional vertigo (BPPV) remains obscure in many cases and women are affected more often than men. A recent prospective study, performed in women >50 years of age suffering from recurrent BPPV, showed associated osteopenia or osteoporosis in a large percentage of these patients. These results suggested the possible relationship between recurrent BPPV and a decreased fixation of calcium in bone in women >50 years. To test this hypothesis, an experimental study was performed in adult female rats. Utricular otoconia of female rats in which osteopenia/osteoporosis was induced by bilateral ovariectomy (OVX) were compared to those of sham-operated adult females rats (SHAM), as control group. FIRST STUDY: The morphology of theutricles of OVX and SHAM rats was analyzed with scanning electron microscopy. In osteopenic/osteoporotic rats, the density of otoconia (i.e. the number of otoconia per unit area) was decreased (p = 0.036)and their size was increased (p = 0.036) compared to the control group. SECOND STUDY: To test the role of calcium turnover in such morphological changes, utricular otoconia of 2 other groups of OVX and SHAM rats, previously injected with calcein subcutaneously, were examined by conventional and epifluorescence microscopy. In epifluorescence microscopy, labeling with calcein showed no significant fluorescence in either group. This finding was interpreted as a lack of external calcium turnover into otoconia of adult female rats. The ultrastructural modifications of otoconia in osteopenic/osteoporotic female adult rats as well as the role of estrogenic receptors in the inner ear are discussed. The possible pathophysiological mechanisms which support the relationship between recurrent BPPV in women and the disturbance of the calcium metabolism of osteopenia/osteoporosis are debated.

Benign paroxysmal positional vertigo in older women may be related to osteoporosis and osteopenia

Benign paroxysmal positional vertigo (BPPV), so-called canalolithiasis and cupulolithiasis, usually occurs after head trauma or viral vestibular neuritis. In many cases, the cause remains obscure, and it often affects women more than 50 years old. The goal of this work was to study a possible relationship between BPPV and osteopenia or osteoporosis. Thirty-two women, whose ages ranged from 50 to 85 years (median age, 69 years), who had BPPV and were free of any other otoneurologic history, were selected. The diagnosis of osteopenia or osteoporosis was confirmed by a bone mineral density measurement made with dual x-ray absorptiometry of spine and hip (T-score). The BPPV was unilateral in 26 patients and bilateral in 6 patients. Our results showed osteopenia or osteoporosis in 24 of the 32 patients (75%) with BPPV. The T-scores were compared in 3 age groups to those of 83 healthy women. The patients with BPPV had a significantly lower (p < .026) T-score in all groups. Possible pathophysiological mechanisms are discussed to explain the apparent correlation between BPPV and osteopenia or osteoporosis.

Photoacoustic effects of carbon dioxide lasers in stapes surgery: quantification in a temporal bone model

HYPOTHESIS

The use of the CO2 laser in stapes surgery creates sound waves that could damage hearing. BACKGROUND The application of a laser to any medium has absorption, reflection, and thermal effects. To date, the majority of research on the safety of CO2 laser stapedotomy has focused on the thermal effects of the laser alone. Because of the properties of the CO2 laser, its absorption also presents some risk to the inner ear. This absorbed energy can be converted to photoacoustic or photochemical effects. The goal of this paper is to measure these photoacoustic effects (sounds) produced by the CO2 laser.

METHODS

Using a variety of settings, a Sharplan 150 XJ Laser and a Contour model Erbium:YAG laser were applied to the oval window of human temporal bones. Perilymph was simulated by fixing the temporal bone in a normal saline bath. Photoacoustic waves were measured by a hydrophone 2 mm beneath the oval window. Measurements were made with and without a simulated tissue seal over the window.

RESULTS

No detectable sounds were created below 4 watts (continuous mode) or 60 mJ (superpulse mode). Above those settings, intensities of 90 dB sound pressure level and higher were detected when the laser was applied directly to the perilymph. With the tissue seal in place, no detectable sounds were identified. The accuracy of this model was confirmed by comparing these results with previously published results using the Erbium:YAG laser.

CONCLUSIONS

Below 4 watts in continuous wave mode and below 60 mJ in superpulse mode, any sound generated by the laser is small. Above these thresholds, however, impact sounds are produced that could result in threshold shifts with repeated applications.

Development and maintenance of otoconia: biochemical considerations

The first part of this review deals with recent advances in the understanding of biochemical mechanisms of otoconial morphogenesis. Most important in this regard is the molecular characterization of otoconin 90, the principal matrix protein of mammalian calcitic otoconia, which was found to be a homologue of the phospholytic enzyme PLA2. The unique and unexpected expression pattern of this protein required radical rethinking of traditional concepts. The new data, when integrated with existing information, provide a rational basis for an explanation of the mechanisms leading to crystal nucleation and growth. Based on this information, a hypothetical model is presented that posits interaction of otoconin 90 with microvesicles derived from the supporting cells as a key event in the formation of otoconia. The second part of the review is directed at the controversial subject of maintenance of mature otoconia and systematically analyzes the available indirect information on this topic. A synthesis of these theoretical considerations is viewed in relation to the pathogenesis of the important otoneurologic entities of BPPN and senile otoconial degeneration. The last part of the review deals with several animal models that promise to help elucidate normal and abnormal mechanisms of otoconial morphogenesis, including mineral deficiencies, mutations with selective otoconial agenesis, as well as targeted disruption of essential genes.