A Pilot Study to Assess Visual Vertigo in People with Persistent Postural-Perceptual Dizziness with a New Computer-Based Tool

BACKGROUND

Visual vertigo (VV) is a common symptom in people with persistent postural-perceptual dizziness (PPPD). Few subjective scales are validated for assessing the intensity of VV, yet these scales are limited by recall bias, as they require individuals to rate their symptoms from memory. The computer-Visual Vertigo Analogue Scale (c-VVAS) was developed by adapting five scenarios from the original paper-VVAS (p-VVAS) into 30 s video clips. The aim of this pilot study was to develop and test a computerized video-based tool for the assessment of visual vertigo in people with PPPD.

METHODS

PPPD participants (n = 8) and age- and sex-matched controls (n = 8) completed the traditional p-VVAS and the c-VVAS. A questionnaire about their experiences using the c-VVAS was completed by all participants.

RESULTS

There was a significant difference between the c-VVAS scores from the PPPD and the control group (Mann-Whitney, p < 0.05). The correlation between the total c-VVAS scores and the total c-VVAS scores was not significant (r = 0.668, p = 0.07). The study showed a high acceptance rate of the c-VVAS by participants (mean = 91.74%).

CONCLUSION

This pilot study found that the c-VVAS can distinguish PPPD subjects from healthy controls and that it was well-received by all participants.

Using interpretative phenomenological analysis to probe the lived experiences of persistent postural-perceptual dizziness (PPPD)

BACKGROUND

Persistent Postural-Perceptual Dizziness (PPPD) is a chronic neuro-vestibular condition characterised by subjective dizziness, non-spinning vertigo, and postural imbalance. Symptoms are typically induced by situations of visuo-vestibular conflict and intense visual-motion.

OBJECTIVE

Little research has focused on the lived experiences of people with PPPD. Therefore, our objective was to present an in-depth exploration of patient experiences and sense-making, and the effect of PPPD on psycho-social functioning.

METHODS

We conducted semi-structured interviews with 6 people with PPPD, who were recruited from an Audiovestibular department in Wales. We present a case-by-case Interpretive Phenomenological Analysis (IPA) for each participant and present common themes.

RESULTS

Our analysis revealed a range of superordinate and subordinate themes, individualised to each participant, but broadly described under the following headings: dismissal and non-belief, identity loss, dissociative experiences, poor psychological well-being and processes of sense-making.

CONCLUSION

The qualitative experiences documented in this study will help clinicians and researchers to better understand the lived experiences of PPPD, how PPPD patients make sense of their symptoms, and the psycho-social impacts of the condition.

Categorizing individuals based on the severity of Visual Vertigo Analogue Scale symptoms

BACKGROUND

The Visual Vertigo Analogue Scale (VVAS) assesses visual vertigo. Instead of the original scoring methods (positive VVAS > 1), we propose categorizing patients as having No (0), Mild (0.1-40), Moderate (40.01-70), or Severe (70.01-100) symptoms.

OBJECTIVE

Our primary aim was to validate an alternative interpretation of the VVAS by exploring the relationship between categories of visual vertigo symptoms and measures of activity and participation, dizziness handicap, anxiety, and depression. We aimed to describe the severity of visual vertigo reported by patients in different vestibular diagnostic categories.

METHODS

Participants with vestibular disorders (n = 250) completed the VVAS, Vestibular Activities and Participation (VAP) Measure, Dizziness Handicap Inventory (DHI), and the Hospital Anxiety and Depression Scale (HADS).

RESULTS

Patients with central disorders were more symptomatic than those with peripheral vestibular disorders. As evaluated by one-way ANOVA, the scores on the VAP, HADS, and DHI significantly differed among mild, moderate, severe, and no visual vertigo categories (p < 0.001). As VVAS severity increased, activity and participation decreased (r = 0.582, p < 0.001); dizziness handicap increased (r = 0.597, p < 0.001, n = 199); anxiety increased (r = 0.405, p < 0.001); and depression increased (r = 0.521, p < 0.001).

CONCLUSIONS

The findings of this study support the use of an alternative VVAS interpretation method of categorizing symptoms as none, mild, moderate, and severe visual vertigo.

Acetazolamide: A New Treatment for Visual Vertigo

Visual vertigo is a disorder characterised by symptoms of dizziness, vertigo, unsteadiness, disorientation, and general discomfort induced by visual triggers. It is currently treated with vestibular rehabilitation therapy, with no effective pharmacotherapy available for treatment-resistant cases. The objective of this study was to evaluate the efficacy of oral acetazolamide in improving symptoms of visual vertigo. A comparative case series of adult patients clinically diagnosed with visual vertigo was conducted from January 1992 to May 2015. Patients without a full neurologic or otorhinolaryngologic work-up, negative magnetic resonance imaging (MRI), and an organic cause for their symptoms were excluded. The identified patients were then contacted by phone to complete a voluntary symptom survey. Main outcome was the subjective reported percentage in symptom improvement. Secondary outcomes were subjective improvement by symptom triggers. The participants were retrospectively divided into three groups based on their treatment with acetazolamide: currently on acetazolamide, terminated acetazolamide, or never initiated acetazolamide. Fifty-seven patients met the inclusion criteria and were willing to complete the phone survey (19 currently on acetazolamide, 27 terminated acetazolamide, and 11 never initiated therapy). Overall symptomatic improvement was reported by 18 (94.7%) patients currently on acetazolamide, 18 (66.7 %) who terminated acetazolamide, and 5 (45.5%) who never initiated therapy, varying significantly by group (p = 0.0061). Greatest improvement was reported in symptoms triggered by being a passenger in a car. These results show that acetazolamide has a positive association with improvement of symptoms of visual vertigo.

Persistent postural-perceptual dizziness (PPPD): a common, characteristic and treatable cause of chronic dizziness

Persistent postural-perceptual dizziness (PPPD) is a newly defined diagnostic syndrome that unifies key features of chronic subjective dizziness, phobic postural vertigo and related disorders. It describes a common chronic dysfunction of the vestibular system and brain that produces persistent dizziness, non-spinning vertigo and/or unsteadiness. The disorder constitutes a long-term maladaptation to a neuro-otological, medical or psychological event that triggered vestibular symptoms, and is usefully considered within the spectrum of other functional neurological disorders. While diagnostic tests and conventional imaging usually remain negative, patients with PPPD present in a characteristic way that maps on to positive diagnostic criteria. Patients often develop secondary functional gait disorder, anxiety, avoidance behaviour and severe disability. Once recognised, PPPD can be managed with effective communication and tailored treatment strategies, including specialised physical therapy (vestibular rehabilitation), serotonergic medications and cognitive-behavioural therapy.

Vestibular rehabilitation following surgical repair for Superior Canal Dehiscence Syndrome: A complicated case report

Superior Canal Dehiscence Syndrome (SCDS) causes auditory and vestibular symptoms. Following surgical repair of the dehiscence, patients often experience dizziness and imbalance. This case report describes a postoperative vestibular exercise program, focusing on the principles of central compensation and habituation, and how it was modified for a patient with delayed progress secondary to strabismus and visual vertigo. A 63-year-old male with history of strabismus eye surgery, right hearing loss, aural fullness, and sensitivity to loud sounds was referred for vestibular rehabilitation (VR). He was seen for one preoperative and six postoperative PT visits over eight months. Outcome measures two weeks postoperative were as follows: Dizziness Handicap Inventory (DHI) 38/100; Timed Up & Go (TUG) 9.92 seconds; Dynamic Gait Index (DGI) 16/24; and a 3-line difference in Dynamic Visual Acuity (DVA). Improved outcomes at discharge included: DHI 18/100; TUG 6.87 seconds; DGI 23/24; and 1-line difference in DVA. He was able to return to work and previously enjoyed recreational activities. Postoperative vestibular rehabilitation programs are functionally and symptomatically beneficial following surgical repair for SCDS. Deviations from expected recovery should be addressed to achieve optimal outcomes as demonstrated in this complicated case report.

Diagnostic criteria for persistent postural-perceptual dizziness (PPPD): Consensus document of the committee for the Classification of Vestibular Disorders of the Bárány Society

This paper presents diagnostic criteria for persistent postural-perceptual dizziness (PPPD) to be included in the International Classification of Vestibular Disorders (ICVD). The term PPPD is new, but the disorder is not. Its diagnostic criteria were derived by expert consensus from an exhaustive review of 30 years of research on phobic postural vertigo, space-motion discomfort, visual vertigo, and chronic subjective dizziness. PPPD manifests with one or more symptoms of dizziness, unsteadiness, or non-spinning vertigo that are present on most days for three months or more and are exacerbated by upright posture, active or passive movement, and exposure to moving or complex visual stimuli. PPPD may be precipitated by conditions that disrupt balance or cause vertigo, unsteadiness, or dizziness, including peripheral or central vestibular disorders, other medical illnesses, or psychological distress. PPPD may be present alone or co-exist with other conditions. Possible subtypes await future identification and validation. The pathophysiologic processes underlying PPPD are not fully known. Emerging research suggests that it may arise from functional changes in postural control mechanisms, multi-sensory information processing, or cortical integration of spatial orientation and threat assessment. Thus, PPPD is classified as a chronic functional vestibular disorder. It is not a structural or psychiatric condition.

Multisensory integration in balance control

This chapter provides an introduction to the topic of multisensory integration in balance control in, both, health and disease. One of the best-studied examples is that of visuo-vestibular interaction, which is the ability of the visual system to enhance or suppress the vestibulo-ocular reflex (VOR suppression). Of clinical relevance, examination of VOR suppression is clinically useful because only central, not peripheral, lesions impair VOR suppression. Visual, somatosensory (proprioceptive), and vestibular inputs interact strongly and continuously in the control of upright balance. Experiments with visual motion stimuli show that the visual system generates visually-evoked postural responses that, at least initially, can override vestibular and proprioceptive signals. This paradigm has been useful for the study of the syndrome of visual vertigo or vision-induced dizziness, which can appear after vestibular disease. These patients typically report dizziness when exposed to optokinetic stimuli or visually charged environments, such as supermarkets. The principles of the rehabilitation treatment of these patients, which use repeated exposure to visual motion, are presented. Finally, we offer a diagnostic algorithm in approaching the patient reporting oscillopsia - the illusion of oscillation of the visual environment, which should not be confused with the syndrome mentioned earlier of visual vertigo.

Magnetic resonance brain imaging in patients with visual vertigo

INTRODUCTION

Patients with visual vertigo (VV) report dizziness provoked by moving visual surroundings. It has been suggested that these subjects develop a compensation strategy for a vestibulo-proprioceptive deficit and rely excessively on visual input. We have postulated that patients with VV might have brain abnormalities that interfere with appropriate processing of visual stimulation and performed a brain MRI study to verify this hypothesis.

MATERIALS AND METHODS

Patients with VV of more than 3 months duration were included. They were asked to complete the Situational Characteristic Questionnaire (SCQ) that scores for the symptoms of VV. Dizzy patients without VV served as controls. A brain MRI was performed with a Siemens 1.5 Tesla scanner in patients and controls.

RESULTS

Twenty-four patients with VV were included. Their mean SCQ score was 1.45 ± 0.9 (normal 0.16 ± 0.28). In 50% of patients, abnormalities in MRI imaging were found. Thirty-three percent of 27 controls demonstrated an abnormal brain MRI. The two groups were similar in respect to the prevalence of a localized hemispheric or posterior fossa lesion (P = 0.13), but VV patients had more unspecific white matter brain changes than controls (P = 0.009). Patients and controls did not differ in age and gender distribution (P = 0.9) or the history of a neurotological event preceding their symptoms (P = 0.3).

CONCLUSIONS

Our study suggests that multiple white matter lesions might contribute to occurrence of the phenomenon of VV. Future prospective large-scale studies by specific MR techniques are indicated to validate our preliminary findings and elucidate the pathological mechanism of VV.