Dizziness

Original Editor - Maryellen Tighe, PT, DPT Top Contributors - Maryellen Tighe, PT, DPT, Vidya Acharya and Alexandra Stead

Introduction

Dizziness is a broad term encompassing a range of symptoms including light-headedness, unsteadiness, and vertigo (the sensation that the environment or oneself is spinning). It is a fairly common condition, with a 2017 study, reviewing population-level data from the United States in 2008, found that 14.8% of people would experience dizziness or balance problems in a year. Other studies have estimated 15-35% of people will be affected over their lifetimes. The highest estimates suggest that it affects more than 50% of people over 60, with the incidence increasing with age.

Dizziness can be divided into central nervous system or peripheral nervous system aetiology. The most common peripheral causes of dizziness are benign paroxysmal positional vertigo (BPPV), vestibular neuritis and Ménière disease. Less common diagnoses include: acute coronary syndrome (secondary symptom), anaemia, aortic dissection, arrhythmia, behavioural health concerns, ectopic pregnancy, hormonal imbalance, infection, metabolic disorders, otosclerosis, pulmonary embolism, thyroid disease, and vasovagal reflex. The most common central causes of dizziness are vestibular migraines and vertebrobasilar ischaemia. Less common diagnoses include: cerebellopontine angle tumours, craniocervical dissection, encephalitis, intracranial haemorrhage, meningitis, multiple sclerosis, and seizures.

Clinically Relevant Anatomy

Internal ear with anatomy labeled.

The vestibular system sits within the inner ear. With vision and somatosensation, it co-ordinates eye-head movements and maintains postural orientation. It is composed of three parts:

• Peripheral apparatus (bony & membranous labyrinth: semi-circular canals and otolith organs)
• Central processors (vestibular nuclei and cerebellum)
• Motor outputs (vestibulo-ocular, vestibulo-spinal and vestibulo-collic reflexes)

The cervical spine is comprised of 7 vertebrae, which support the head and the neck and allow for movement. Errors in processing positional information in this region can cause dizziness and unsteadiness.

Causes and Pathological Processes

Dizziness may be caused by a wide variety of conditions, stemming from many different pathological processes. The most common are:

• benign paroxysmal positional vertigo: a condition where calcium-carbonate crystals (otoconia) become displaced from the otolith organs into one of the semi-circular canals, causing vertigo, nystagmus, and occasionally nausea.
• vestibular neuritis: an inflammation of the vestibular branch of the vestibulocochlear nerve (CN VIII), typically preserving hearing.
• Ménière disease: a progressive idiopathic inner ear disorder causing episodic vertigo, hearing loss, and tinnitus.
• vestibular migraines: a type of migraine which may not include a headache but has similar triggers and symptoms to headache type migraines including: visual aura, or sensitivity to visual stimulation and motion.
• vertebrobasilar ischaemia: a transient reduction in blood flow through the vertebral and basilar arteries to the posterior structures of the brain.

Some other examples include:

• orthostatic hypotension, an autonomic response to standing where blood pressure drops more than normal resulting in potential faints or falls.
• hypoglycaemia, when blood glucose levels fall.
• thiamine deficiency, a condition impacting parts of the brain reliant on thiamine causing nystagmus, ataxia and potentially memory problems.

These causes of dizziness can be clinically classified into four categories: vertigo, disequilibrium, presyncope, or light-headedness. Vertigo includes benign paroxysmal positional vertigo, Ménière disease, vestibular neuritis, and labyrinthitis. Presyncope is the sensation that one is about to faint without fainting, which can be caused by many types of medications. Disequilibrium may be associated with Parkinson's disease and diabetic neuropathy. Finally, vague light-headedness can be caused by psychiatric disorders such as depression, anxiety and hyperventilation syndrome.

Diagnostic Procedures

When people seek treatment for dizziness, 61% report experiencing more than one type of dizziness. A subjective screen will help determine the cause of dizziness.

TiTraTE

A 2018 approach suggests dividing patients into three categories using timing and triggers. The first distinction is for acute vestibular syndrome, where the clinician would differentiate vestibular neuritis or a stroke. The second category would be spontaneous episodic vestibular syndrome, where a clinician would differentiate between a vestibular migraine and a transient ischaemic attack. Finally the third category would be triggered episodic vestibular syndrome, where a clinician will differentiate between benign paroxysmal positional vertigo and posterior fossa structural lesions.

Another way of thinking about this is using the TiTraTE mnemonic:

• Ti: Timing of the symptoms
• Tr: triggers that provoke the symptoms
• aTE: a Targeted Examination

Ti: (Timing) This will help distinguish between episodic and continuous dizziness. Episodic dizziness lasts for seconds to hours. Continuous dizziness lasts for days to weeks.

Tr: (Triggers) Look for actions, movements, or situations that provoke dizziness in patients with intermittent symptoms. Both peripheral and central pathologies can be triggered by positional changes, such as head position testing for benign paroxysmal positional vertigo and transfers from supine to sitting or standing for orthostatic hypotension.

Dix Hallpike Manoeuvre for testing the left ear.

aTE: (a Targeted Examination) If a patient has triggered episodic vestibular symptoms, follow up with a Dix-Hallpike and orthostatic vitals to differentiate between the two conditions. Orthostatic hypotension is a reduction in systolic blood pressure of at least 20 mmHg or diastolic blood pressure of at least 10 mmHg three minutes after standing from a supine or sitting position. A Dix-Hallpike manoeuvre can rule in benign paroxysmal positional vertigo if the patient demonstrates transient upbeating torsional nystagmus. A negative test does not rule out BPPV.

HINTS

For patients with continuous dizziness, the next step is to determine a central versus peripheral cause of dizziness, using the mnemonic HINTS (head impulse, nystagmus, test of skew). This will allow a clinician to determine if the cause of dizziness is vestibular neuritis or stroke.

Head impulse

In this test the examiner holds the patient's head and makes a small, rapid, unpredictable horizontal rotation toward the examiner. The patient is asked to maintain fixation on the examiner's nose throughout. A positive test is a saccade (rapid movement of both eyes in which the gaze overcorrects to keep focused on the examiner). If a patient has continuous dizziness, the clinician would expect an abnormal result for peripheral causes. If they have a normal test with continuous dizziness that indicates a central pathology.

Nystagmus

The patient may have primary or spontaneous nystagmus, which is nystagmus at baseline. They may also have gaze evoked nystagmus. If the nystagmus is unidirectional and horizontal, it suggests a peripheral cause. Suppression of nystagmus with visual fixation also usually indicates peripheral vertigo.  Primarily vertical, torsional or bidirectional nystagmus indicates a central cause.

Test of Skew

Test of skew is assessed by asking the patient to look straight ahead, then covering and uncovering each eye. Vertical (up or down) deviation of the covered eye after uncovering is an abnormal result suggesting central pathology.

Outcome Measures

Potential outcome measures for dizziness overlap with balance and the cervical spine. They include:

• Dizziness Handicap Inventory (DHI)
• Neck Disability Index (NDI)
• Activities Balance Confidence (ABC)
• Falls Efficacy Scale
• Dizziness Handicap Inventory (DHI)
• Balance Evaluation Systems Test (BESTest)
• Berg Balance Scale
• Functional Gait Assessment (FGA)
• Performance Oriented Mobility Assessment (POMA)
• UCLA Dizziness Questionnaire
• Activities of Daily Living Questionnaire (ADLQ)
• Vestibular Disorders Activities of Daily Living Scale (VADL)
• Prototype Questionnaire
• Vertigo Handicap Questionnaire (VHQ)
• Vestibular Rehabilitation Benefit Questionnaire

Clinician administered testing is also effective for tracking changes in dizziness, including:

• Gait speed
• Timed Up and Go (TUG)
• Dynamic Gait Index (DGI)
• modified Clinical Test of Sensory Integration and Balance (mCTSIB)

Management / Interventions

Physical therapy interventions

Interventions will vary based on the cause of the dizziness, which can be determined using the methods above. Dizzy patients, regardless of the diagnosis, experience less injurious falls over a 12 month time period if they start physical therapy within three months of their symptoms starting.

For BPPV, a canalith repositioning procedure (e.g., Epley manoeuvre) is a good first-line intervention.

For patients with vestibular hypofunction, habituation training, including balance training and gaze stabilisation exercises, is an appropriate intervention. Gaze stabilisation or vestibulo-ocular reflex (VOR) adaption exercises can be performed in a lighted room with active eye and head movements. The exercise can be progressed by modifying the distance from the target, the speed of the eye and the head movements, the plane of the head movement, the base of the support, support surface compliance, the amount of light, and the posture of the subject. The time that it takes for these exercises to improve dizziness is still being studied, though home exercise programme compliance is associated with better outcomes at one year than discontinuing the exercises at home. Clinic-based interventions may last from one week to several months. These interventions are shown to be particularly effective for people whose dizziness is worsened in social situations or in situations with head movements. Optokinetic Stimulation may help improve enjoyment of and adherence to a vestibular therapy program.

For symptoms originating centrally, it may be appropriate to refer the patient to another provider. Cervical manipulation can improve proprioception and dizziness for these patients, while acupuncture can reduce the perceived dizziness. And research supports habituation or vestibular rehabilitation as described above for these patients to improve their ability to compensate for their balance limitations.

Cervicogenic dizziness may be effectively treated by acupuncture, according to a 2014 meta analysis. And a 2005 systematic review found that manual therapy shows promising results for cervicogenic dizziness treatment.

It is not yet clear if Persistent Postural-Perceptual Dizziness (PPPD), a type of dizziness where being upright and dynamic visual environments worsen your symptoms, responds well to habituation training as described above due to the heterogeneity of the interventions.

If the patients dizziness is as a result of a concussion, the clinician should start with BPPV and cervicogenic dizziness treatments as appropriate in the first three weeks after the injury, then follow with vestibular therapy as described above for the best clinical and patient-reported outcomes. There is research supporting auditory biofeedback (e.g. changing the volume of a sound by changing your position) instead of visual feedback during physical therapy sessions for resolution of unsteadiness following a concussion.

Additional interventions

Pharmacological management may include antihistamines and vestibular suppressants.

For patients with PPPD, symptoms may be improved by emotion-focused integrative treatment approaches, which combines cognitive reframing with acupoint tapping, according to some preliminary evidence. These patients may also respond to Cognitive Behavioural Therapy visual desensitization (i.e. optokinetic stimulation) and vagus nerve stimulation.

Summary

Dizziness is a broad collection of symptoms which has the potential to affect people across their lifespan. Physical therapists can differentiate dizziness which will respond to their interventions can, such as vertigo or cervicogenic, from dizziness which is related to other causes such as migraines, hormone imbalances or medication management. Once it is determined that physical therapy is the appropriate course of care, it may take just a few visits to resolve an issue such as benign paroxysmal positional vertigo, or the patient may start a course of care which involves regular visits for months, such as balance training for patients with Parkinson's Disease.