Cause:
Our inner ear is composed of hollow bones (semicircular canals) filled with fluid, the position of the fluid within the bones informs our brain of our head’s position relative to gravity. Outside of these canals, small crystals made of calcium carbonate exist which perform a similar role in providing sensory information. These crystals can however dislodge and become trapped in the fluid. As the crystals are not in their usual position, the brain receives two conflicting sets of information regarding our head position which results in dizziness known as vertigo.
This specific cause of vertigo is referred to as BPPV as it relates to the position of the head and as such is often triggered by rolling in bed, fast head movements, or rotating the head to look over one’s shoulder. The cause of BPPV is idiopathic (arises spontaneously), it is more common in the elderly (>60yrs) but can occur after head trauma or prolonged bed rest.
Signs & Symptoms:
If your Vertigo is cause by BPPV, you may experience symptoms in the following manner:
Paroxysmal – Sudden onset of symptoms lasting seconds to a few minutes (1-3 minutes)
Positional onset – Symptoms primarily brought on by looking in a specific direction
Nausea/vomiting – depending on the intensity of the vertigo
Nystagmus – the eyes pulse towards the affected side. This should last approximately seconds to a minute and should decrease in intensity over that time.
Diagnosis & Treatment:
BPPV can be diagnosed by your Physiotherapist or General Practitioner by taking a careful history and performing the Dix-Hall Pike Test. This test involves positioning the head in such a way to disturb the crystals of the inner ear, it is considered positive if symptoms are reproduced.
If you have tested positive for BPPV, your Physiotherapist can perform a repositioning manoeuvre designed to relocate the crystals from where they have become lodged. The most common and successful treatment is the Epley manoeuvre however, other types can be administered depending on the location of the crystals. Most cases can be resolved in 1-3 treatment sessions and the patient should have a resolution of symptoms in approximately 1-2 weeks. Be aware, there are certain protocols that must be followed once the treatment is performed to ensure the crystals do not dislodge again.
If symptoms persist following this treatment, it is important to return to your General Practitioner or Physiotherapist to consider other diagnoses. Medical imaging or a neurological assessment may be indicated.