Revisiting "Meniere's Disease" as "Cervicogenic Endolymphatic Hydrops" and Other Vestibular and Cervicogenic Vertigo as "Spectrum of Same Disease": A Novel Concept

Cervicogenic Somatic Tinnitus: A Narrative Review Exploring Non-otologic Causes

Cervicogenic somatic tinnitus (CST) is a subgroup of somatosensory tinnitus that arises from altered sensory input from the cervical spine due to changes in anatomical and physiological functions. Unlike primary tinnitus, usually caused by auditory system issues, CST is due to somatosensory disruptions from the cervical region. Conditions such as degenerative disc disease, cervical spondylosis, whiplash injuries, and neck muscle stress or spasms are commonly associated with CST. The pathophysiology of CST involves complex interactions between the cervical spine's somatosensory inputs and central auditory pathways, particularly affecting the dorsal cochlear nucleus (DCN) in the brainstem, leading to enhanced excitability and synaptic reorganization, giving rise to tinnitus. Accurate diagnosis and management of CST require a comprehensive approach, including patient history, physical examination, audiological assessments, and imaging studies. Treatment strategies encompass physical therapy, medications, interventional procedures, and complementary therapies, aiming to reduce tinnitus perception, alleviate neck dysfunction, and improve overall quality of life. Emerging therapies, such as neuromodulation and regenerative medicine, show promise in further improving CST management. This multidisciplinary approach highlights the importance of addressing both musculoskeletal and auditory health in the effective treatment of CST.

Vestibular, Central, and Non-Vestibular Etiologies of Vertigo and Disequilibrium: A Rural Hospital-Based Cross-Sectional Comparative Analysis

INTRODUCTION

Vertigo/dizziness is defined as disturbed postural awareness and could range from a feeling of sensation of spinning of self or surrounding. Dizziness or disturbed postural awareness is a common presentation in varying age groups. Vertigo has varied clinical presentations. Classically, there are four vertigo syndromes: vertigo, imbalance/disequilibrium, presyncope/lightheadedness, and psychogenic dizziness. The present study was conducted to examine the various etiologies involved in these syndromes and to help unmask the overlaps between them. This study also aimed to further classify the etiologies underlying these vertigo syndromes and overlaps into peripheral or vestibular, central, and non-vestibular. This would help develop a comprehensive management protocol for vertigo of any origin.

METHODS

A prospective observational cross-sectional study was undertaken in a rural hospital in Central India. We studied patients with giddiness and categorized them into vertigo syndromes according to the site of origin of vertigo. We also compared overlaps in the presentation of vertigo.

RESULTS

Out of the 80 patients that were studied, vertigo with disequilibrium was observed in 72.50% of the patients. Non-vestibular vertigo of cervicogenic origin was the common cause of vertigo seen in 36.25% of the patients occurring alone or in association with vestibular vertigo. Among patients with overlaps, vestibular vertigo with non-vestibular vertigo was the most common etiology observed in 89.65% of the patients with overlaps.

CONCLUSION

The syndrome of "vertigo with disequilibrium" was the commonest presentation in the patients studied, followed by "vertigo syndrome" as an isolated symptom, not associated with "disequilibrium." Ours is probably the first study to report this observation of overlaps of two syndromes, with diagnostic implications.

Proprioceptive Cervicogenic Dizziness Care Trajectories in Patient Subpopulations: A Scoping Review

Proprioceptive cervicogenic dizziness (PCGD) is the most prevalent subcategory of cervicogenic dizziness. There is considerable confusion regarding this clinical syndrome's differential diagnosis, evaluation, and treatment strategy. Our objectives were to conduct a systematic search to map out characteristics of the literature and of potential subpopulations of PCGD, and to classify accordingly the knowledge contained in the literature regarding interventions, outcomes and diagnosis. A Joanna Briggs Institute methodology-informed scoping review of the French, English, Spanish, Portuguese and Italian literature from January 2000 to June 2021 was undertaken on PsycInfo, Medline (Ovid), Embase (Ovid), All EBM Reviews (Ovid), CINAHL (Ebsco), Web of Science and Scopus databases. All pertinent randomized control trials, case studies, literature reviews, meta-analyses, and observational studies were retrieved. Evidence-charting methods were executed by two independent researchers at each stage of the scoping review. The search yielded 156 articles. Based on the potential etiology of the clinical syndrome, the analysis identified four main subpopulations of PCGD: chronic cervicalgia, traumatic, degenerative cervical disease, and occupational. The three most commonly occurring differential diagnosis categories are central causes, benign paroxysmal positional vertigo and otologic pathologies. The four most cited measures of change were the dizziness handicap inventory, visual analog scale for neck pain, cervical range of motion, and posturography. Across subpopulations, exercise therapy and manual therapy are the most commonly encountered interventions in the literature. PCGD patients have heterogeneous etiologies which can impact their care trajectory. Adapted care trajectories should be used for the different subpopulations by optimizing differential diagnosis, treatment, and evaluation of outcomes.

Clinical, oculographic and vestibular test characteristics of Ménière's disease

Seventy Ménière's disease (MD) patients with spontaneous vertigo (100%), unilateral aural fullness (57.1%), tinnitus (78.6%), and subjective hearing loss (75.7%) self-recorded nystagmus during their episodes of vertigo using portable video oculography goggles. All demonstrated ictal spontaneous nystagmus, horizontal in 94.3% (n = 66) and vertical in 5.7% (n = 4), with a mean slow-phase velocity (SPV) of 42.8 ± 31.1°/s (range 5.3-160.1). Direction reversal of spontaneous horizontal nystagmus was captured in 58.6%, within the same episode in 34.3%, and over different days in 24.3%. In 18.6%, we observed ipsiversive then contraversive nystagmus, and in 12.9% contraversive to ipsiversive direction reversal. Ictal nystagmus SPV (42.8 ± 31.1°/s) was significantly faster than interictal (1.4 ± 3.1°/s, p < 0.001, CI 34.277-48.776). Compared to age-matched healthy controls, interictal video head impulse test gains in MD ears were significantly lower, cumulative and first saccade (S1) amplitudes were significantly larger, and S1 peak velocities were significantly faster (p = 0.038/0.019/0.008/ < 0.001, CI 0.002-0.071/0.130-1.444/0.138-0.909/14.614-41.506). Audiometry showed asymmetrically increased thresholds in 100% of MD ears (n = 70). Significant caloric, air-conducted (AC) cervical vestibular-evoked myogenic potential (VEMP), and AC ocular VEMP asymmetries were found in 61.4, 37.9, and 44.4% of patients (MD ear reduced). Transtympanic electrocochleography tested in 36 ears (23 patients) showed 81.8% of MD ears had a positive result for hydrops (either a summating potential at 1/2 kHz < - 6 µV, or an SP/AP ratio > 40%). Using ictal nystagmus findings of SPV > 12°/s, and a caloric canal paresis > 25%, we correctly separated a diagnosis MD from Vestibular Migraine with a sensitivity and specificity of 95.7% and 85.1% (CI 0.89-0.97).