Table 2: Canal Repositioning Maneuvers for BPPV Maneuvers Canal Initial Position
Treatment
Epley
Anterior or Posterior Canalithiasis Posterior Cupulolithiasis
Patient in supine with 20° neck extension and 45° head rotation to affected side. Affected side down , 45° head rotation away from affected side ( nose up ). Affected side down , 45° head rotation toward affected side ( nose down ). Sidelying on unaffected side for 2 minutes. Sidelying on affected side without cervical rotation. Supine, head turned toward affected side.
2 subsequent positions: head rotation to opposite side, then continue with trunk and head rotation, then to sit. Move quickly to lying on unaffected side (through returning to sit), without rotating head (nose down).
Semont
Semont
Anterior Cupulolithiasis
Move quickly to lying on unaffected side (through returning to sit), without rotating head (nose up).
Appiani
Horizontal Canalithiasis Horizontal Cupulolithiasis Horizontal Canalithiasis
Quick 45° cervical rotation toward unaffected side (nose down). Immediate quick 45° cervical rotation toward affected side (nose down). Maintain 3 minutes. 3 subsequent steps: head roll to opposite side, patient rolls to side, patient rolls to prone.
Casani (aka Modified Semont)
Barbeque Roll (270° roll)
Vestibular hypofunction As previously discussed, spontaneous rebalancing of tonic inputs occurs within 2 weeks for the patient with altered vestibulo-ocular and vestibulospinal responses due to disruption of function in CN VIII or the otoliths. Patients presenting with residual deficits in postural control, gaze stabilization, and symptoms of dizziness due to vestibular hypofunction require a program of vestibular rehabilitation. A wealth of studies demonstrates that recovery of the disturbances due to loss of peripheral vestibular function is dependent on activities that incorporate visual inputs and head and body movement (Gill-Body et al., 1994; Herdman, 1998; Herdman, Blatt, et al., 2000; Herdman, Clendaniel, et al., 1995; Herdman, Schubert, et al., 2003; Whitney & Rossi, 2000), which is the basis for vestibular rehabilitation. Vestibular rehabilitation programs should include habituation exercises, adaptation exercises as warranted for patients with impaired gaze stabilization, balance retraining, and exercises to restore or maintain physical conditioning. Habituation exercises Habituation exercises are performed to reduce symptoms of motion-provoked dizziness or imbalance. The underlying principle of habituation exercises is to reduce the CNS response to normal movement stimulus, or “habituating,” driving compensation in the CNS. Any head motion that the patient finds symptomatic, such as bending forward or walking with head turns, can be used as a habituation exercise. However, a habituation program should also incorporate the items in the MSQ; the MSQ is composed of the most common activities that provoke dizziness in patients with peripheral vestibular hypofunction, and is a valuable tool to document recovery (Shepard et al., 1990; Smith-Wheelock et al., 1991). The patient starts with 4 to 5 of the activities on the MSQ that moderately provoke their symptoms, repeating three times and performing them two to three times daily, resting between each exercise to allow the symptoms to return to baseline. Habituation is characterized by decreased intensity and duration of symptoms in response to performing the exercise. Once patients can tolerate an activity, with minimal or no symptoms, they can be progressed to other items on the MSQ that they found more provocative. The clinician should be careful not to overprescribe habituation exercises at the risk of overstimulating the patient. In order to drive CNS neuroplasticity and habituation, exercises must provoke symptoms, but symptoms should resolve within a few
minutes. Symptoms lasting an hour or more necessitate a review of how the patient is performing the exercises and program modification. The patient may need to perform exercises for a few months before being able to modify the program, and may take as long as 6 months for habituation to take place, although incremental recovery should be observed to determine efficacy (Herdman & Clendaniel, 2014; Smith-Wheelock et al., 1991). Gaze stabilization (adaptation) exercises Gaze stabilization exercises, also called “adaptation exercises,” have been found to be effective in restoring the VOR gain (1:1 ratio of head-eye movement) in patients with vestibular dysfunction who are experiencing blurred vision or dizziness when performing activities that require visual tracking during head movement (Hillier & McDonnell, 2011). Not all patients with vestibular loss will experience difficulties with gaze stabilization, but positive findings on DVA testing or symptoms of blurred vision while walking or scrolling text on their computer screen are indicative of diminished gaze stabilization. Gaze stabilization exercises require the patient to maintain visual fixation on a target while moving the head. Visual fixation is mediated by the CNS. During visual fixation on a stationary object, any slip of the image on the retina due to drifts in ocular position will cause the brain to generate a responsive eye movement to hold the image steady on the retina. The retinal “slip” of the image on the fovea during head motion due to the altered VOR gain induces centrally mediated changes in interpretation of vestibular signals from the residual vestibular function. The retinal “slip” produces an error signal, and the CNS compensates to decrease the error signal by increasing the VOR gain. Retinal slip can be induced by both horizontal and vertical head movements applied at various amplitudes and frequencies to allow for adaptive changes to occur in the VOR gain. These changes, or adaptation, are the basis for restoring adequate VOR function. The first level of the exercise is termed X1 (“times one”) viewing. It has the patient fix gaze on a discrete target, such as a card with a single letter on it, which is held at arm’s length. The patient moves his or her head in a small trajectory (20° to 30°) from side to side as fast as possible while maintaining a clear focus on the target (see Resources section for link). He or she should continue the motion for 1 minute without stopping, modulating the speed of the head
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