Interventions for Vestibular System Disorders

• Benign paroxysmal positional vertigo (BPPV)


  A mechanical disruption that can be corrected
• Particle repositioning maneuver


  Guide the patient's head through a series of movements consistent with the plane and shape of the affected canal, using endolymph flow to clear the otoconia
• Cupulolithiasis


  Otoconia adhered to the cupula
• Canalith Repositioning Maneuver (Epley maneuver)


  • Based on the canalithiasis theory of free-floating debris in the semicircular canal, used to treat the canalithiasis form of posterior and anterior semicircular canal BPPV
• Canalith Repositioning Maneuver (Epley maneuver)


  Sequential movement of the head into five positions to move the debris out of the semicircular canal and into the vestibule
• Liberatory or Semont Maneuver


  • Based on the cupulolithiasis theory of debris adhering to the cupula in the semicircular canal, used to treat cupulolithiasis of the posterior and anterior semicircular canal BPPV
• Liberatory or Semont Maneuver


  Rapidly moving a patient from lying on one side to lying on the other to dislodge debris adhering to the cupula
• Bar-B-Que Roll or Lempert Maneuver


  • Used to treat the canalithiasis form of horizontal semicircular canal BPPV
• Bar-B-Que Roll Maneuver


  Moving the head through a series of 90-degree angles and pausing between each turn for 10–30 seconds
• Compensation


  Substitution of other structures for lost vestibular function
• Adaptation


  Reestablishment of the gain, phase, or direction of the VOR by the cerebellum
• Habituation


  Decreased response to a nonpainful stimulus after repeated stimuli
• Recovery of function after unilateral vestibular loss

  Functional recovery of hair cells or vestibular nerves, spontaneous rebalancing of the tonic firing rate centrally, adaptive changes in the residual vestibular system, the substitution of alternative strategies, and habituation of unpleasant sensations
• Recovery of gaze stability in bilateral vestibular hypofunction (BVH)

  Central preprogramming of eye movements and modifications in saccadic and smooth pursuit eye movements
• Recovery for individuals with bilateral vestibular deficits is slower than for unilateral lesions and may take up to 2 years
• Recovery from central lesions is often prolonged, ≥6 months and may be incomplete because areas of the central nervous system that are likely responsible for adaptive mechanisms may be damaged by the initial lesion
• Restoration of postural control relies heavily on compensation from the visual and somatosensory systems, thus preexisting conditions such as visual impairment or diabetes limit the ability for sensory reorganization
• Early strategies to enhance recovery

  Early mobility and visual stimulation in room light, repeated movement to reduce symptoms via habituation and promote compensation and adaptation, using visual fixation on a stationary target during transitional movements, pausing at points within a transition, enhancing sensory inputs from the body
• Early gait characteristics include wide BOS, veering to one side, increased stepping strategies, reduced head and trunk movements, and using furniture or walls for haptic cues
• Positive head impulse test and dynamic visual acuity tests

  Leads to the movement diagnoses of gaze instability due to VOR loss, appropriate intervention is gaze stabilization exercises

  
• Scores on the Dynamic Gait Index, Functional Gait Assessment, and Timed Up and Go

  Support a movement diagnosis of gait instability due to vestibulospinal reflex loss, appropriate intervention is balance training
• Motion sensitivity movement diagnosis

  Leads to the proper selection of Brandt-Daroff exercises
• Positive Dix-Hallpike or Roll test


  Leads to a movement diagnosis of BPPV and selection of Canalith Repositioning Maneuvers
• VOR X 1 viewing paradigm

  Visual target is stationary, patient moves head back and forth while maintaining visual fixation

  
• VOR X 2 viewing paradigm

  Patient's head and the visual target move in opposite directions while the person keeps the target in focus

  
• Exercises that induce adaptation via retinal slip can facilitate adaptation of the VOR in patients with some vestibular function
• Visual blurring and dizziness


  When performing tasks that require visual tracking or gaze stabilization
• Adaptation of the VOR

  1. Exposing the patient to small amounts of retinal slip

  2. Error signal generated by retinal slip stimulates vestibular adaptation within the brain
• VOR X 2 viewing paradigm

  Patient's head and visual target move in opposite directions while keeping target in focus

  
• Exercises to induce adaptation via retinal slip


  • Can be progressed by increasing directions of head movements, duration and frequency of exercise bouts, speed of head movements, distance and size of target, changing body position
• Saccadic and pursuit eye movements

  Used in exercises for persons with poor or no VOR
• Exercises for persons with poor or no VOR

  1. Active eye movements followed by head movements between two horizontal targets

  2. Visualization of remembered targets

  
• Habituation exercises


  Repeated exposure to provoking positions or movements causes a reduction in the response to the stimuli
• Habituation exercise program


  1. Up to four movements chosen from Motion Sensitivity Quotient

  2. Patient repeats movements 3-5 times, 2-3 times a day, with rests between

  3. Performed quickly enough and through enough range to produce mild to moderate symptoms
• Habituation exercises should be incorporated into the person's daily activities
• Habituation exercises are best performed frequently throughout the day, but for short durations of time
• Saccades


  Trained by alternatively looking at two objects in the near visual field, practiced in both horizontal and vertical planes

  
• Smooth pursuit


  Trained by focusing on a moving target without head movement
• Postural control exercises


  Aim to improve the patient's balance control and prevent falls
• Postural control interventions


  • Consider impairments across all systems, rehabilitate or compensate/substitute, include head movements, incorporate motor learning concepts, emphasize safety and function