By Dr. Vishal Pawar, Specialist Neurologist, DNB Neuro, SCE Neurology (RCP, UK), VAM (The American Institute of Balance), and Vertigo clinic, Aster Specialty Medical Center, International City, Dubai
Vertigo and dizziness rank among the most common reasons for neurological consultation. Dizziness and vertigo affect about 15 per cent to over 20 per cent of adults yearly in large population-based studies. The prevalence of dizziness rises with age and it is about two to three times higher in women than in men.
If we apply the incidence statistics for instance to the current population of Dubai (3.1 million), approximately 4,65,000 to 6,20,000 adult population suffer from some form of dizziness and vertigo every year.
Dizziness or giddiness is a symptom which encompasses a variety of sensations experienced by the patients. It includes vertigo, blackout, imbalance of gait, confusion, light-headedness, whirling, spinning, reeling, rotating, movement of the environment, tilting, falling, pushing, rocking sensation, drunken walking, unsteadiness, swaying, visually induced vertigo, head motion induced dizziness etc.
There are five different types of dizziness.
First is ‘Vertigo’, which means the patient feels the illusory movement of head or surroundings i.e. spinning of head or environment.
The second type is ‘Syncopal dizziness’ in which the patient feels blackout or lightheaded, which may or may not be followed by loss of consciousness.
The third type is ‘Dysequilibrium dizziness’ in which the patient feels imbalance on standing and or while walking.
The fourth type of dizziness is particularly seen in elderly due to deficient vision, impaired sensations, and balance control issues. It is called ‘Multisensory deficit dizziness’.
The last and fifth type of dizziness is ill-defined dizziness in which its very difficult for the patient to describe the symptoms. It is usually seen in patients with anxiety and panic disorder.
Vertigo is one of the most common types of dizziness in which patient feels spinning, reeling, whirling, rotating, tilting or pushing sensation. The patient feels either the head is rotating, or the environment is rotating.
Vertigo can be caused by three main categories in the causes.
First one is called Peripheral vertigo, which is the problem in balance control system of the body located in the inner ear. The most common causes of peripheral vertigo are Benign paroxysmal positional vertigo (BPPV), Vestibular neuronitis, Meniere’s disease etc.
The second one is called Central vertigo, which is due to a problem in the balance controlling structures in the brain (Brainstem and small brain). The most common causes of Central vertigo are Vestibular migraine, Stroke, Multiple sclerosis, Tumours etc.
Thirdly, other causes of dizziness like stress, panic disorder, anxiety, dizziness triggered in crowded places (Agoraphobia), dizziness due to complex lights etc.
It is diagnosed by detailed history taking, symptom analysis and focused examination of the patient, which involves specialised positioning manoeuvres done by experts. There are various specialised tests for the diagnosis of vertigo like Video-nystagmography (VNG), MRI Brain, Audiometry, Vestibular evoked myogenic potentials (VEMP), Posturography etc. These tests are requested based on the symptoms described by the patient.
Eyes serve the important function of vision. The movements of eyeballs help in focusing the attention on one target and also in shifting the attention from one target to another target. The eye movements are adjusted according to the position and velocity of the head with the help of widespread brain circuits.
Various diseases can affect these brain circuits and can lead to eye movement abnormalities. Hence, the eyes provide a window for the diagnosis of numerous neurological disorders.
Video-nystagmography (VNG) is an equipment which does video-recording of the eye movements. During the VNG test, the patient wears the VNG goggles and sits in front of a TV screen, which displays various stimuli as shown in the diagram. The eye movements occurring in response to these stimuli are recorded in graphical as well as video format. This record aids in the accurate diagnosis, monitoring and treatment of the neurological disorders.
The most important thing which needs to be understood is ‘Vertigo is a symptom, not a diagnosis’. Hence, the most important step is correct diagnosis of the cause of vertigo. The treatment of the Vertigo differs according to the cause.
If the cause of the Vertigo is benign paroxysmal positional vertigo, the treatment is various repositioning manoeuvres which are done by experts in this field.
If the cause of the Vertigo is Vestibular migraine, the treatment is lifestyle modifications and preventive medications for migraine.
If the cause of the Vertigo is stroke, multiple sclerosis or tumours, we have to treat the underlying disease.
Dr. Pawar discussed ‘Every positional vertigo is not BPPV’ as part of the Audiology & Speech Pathology conference, at ME OTO Exhibition and Conference 2019.