A canalith repositioning procedure (CRP) is a treatment for benign paroxysmal positional vertigo (BPPV), the most common cause of vertigo.
The letters of the term “BPPV” stand for:
The cause of BPPV is the displacement of small crystals of calcium carbonate (also known as canaliths) in the inner ear.
The crystals become trapped in the inner ear’s fluid-filled semicircular canal. Usually the posterior semicircular canal is affected because its structure works with the pull of gravity.
The semicircular canals are normally not sensitive to head and body position changes. With BPPV, however, head and body movements such as lying down cause the crystals to move, which stimulates nerve endings inside the semicircular canals.
The nerves send false signals to the brain, causing dizziness and other unsettling symptoms of vertigo including nausea, vomiting, disorientation or instability, as well as a back-and-forth rhythmic eye movements called nystagmus.
CRP uses a series of changes in head position to move the detached crystals in the inner ear out of the semicircular canals into an adjacent structure called the utricle, a sac where the crystals first formed. Once back in the utricle the crystals can either reattach, dissolve, be broken up or move somewhere else where they won’t cause symptoms.
Anyone with BBPV who can go through the procedure safely may benefit from it. If BBPV returns after CRP, the procedure can be used again to treat recurrences.
CRP is used only for the treatment of BBPV. An examination of the patient should rule out other possible causes of vertigo before CRP is used.
Other causes of vertigo could include:
There the two most common types of CRP available to treat BPPV and called the Epley maneuver and the Semont-Liberatory maneuver. Which one is chosen depends on the results of a Dix-Hallpike test (see next section).
A medical examination will determine if the patient is a good candidate for CRP. People with certain health conditions should not undertake the procedure. These conditions include existing inner ear problems that could be made worse with CRP, detached retina, certain vascular (blood vessel) disorders and esophageal reflux disease.
A Dix-Hallpike test is administered to confirm a diagnosis of BPPV. The patient is laid back onto an examination table in such a position that canaliths (crystals), if present, will trigger vertigo and nystagmus. If the test is positive it will also show if the canaliths are in the right or left ear, and where they are within those. This helps determine the exact movements that will help the most during CRP.
The procedure can be performed in a doctor’s office and usually takes about 15 minutes. An anti-nausea medication may be given beforehand.
CRP uses a specific pattern of head and body movements. It must be delivered by an expert in the procedure to exclude those who are not good candidates, and guard against injury during the procedure.
The exact head movements chosen and the amount of time between movements are based on the location of the crystals within the ear and are determined by the medical team giving the procedure.
Best practice recommendations strongly advice against post-treatment restrictions after CRP for posterior canal BPPV. There is limited medical evidence to support avoiding head movements, sleeping in a reclined position after treatment or avoiding sleeping over the affected ear for days following treatment. However, some consideration of post-treatment restrictions may be made in some cases such as frequently recurring BPPV.
CRP is a unique medical procedure because it does not require any special tools or equipment other than an examination table, and is not invasive in any way. Once the position of the canaliths is determined, the patient is led through the correct series of movements and should find relief quickly.
Possible complications of CRP include injury to the neck or back, or crystals being dislodged and moving to another semicircular canal.
Reviews of CRP find it to have a very high level of effectiveness. A number of studies have been conducted showing that 85-90 percent of patients treated with CRP were relieved of the symptoms of BPPV, compared to only 10-20 percent of untreated patients who found relief.
CRP cures vertigo in about 85 percent of the cases in which it is used. Recurrence of symptoms is infrequent however additional treatments are sometimes needed. CRP may be used again if symptoms return.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition. This document was last reviewed on: 10/22/2018