Benign paroxysmal positional vertigo

The purpose of this case report is to describe the evaluation and treatment of a patient with vertigo. The patient was a 32-year-old male carpenter with a 17-year history of episodic vertigo that occurred when his neck was in the extended position while positioned supine and during walking. His medical and physical therapy evaluative findings were consistent with a diagnosis of benign paroxysmal positional vertigo (BPPV). He was treated with an individualized home exercise program of eye movement exercises, Brandt/Daroff exercises, and general conditioning exercises. Twenty-four days from the start of physical therapy, the patient was free of symptoms even when his neck was in the extended position. [Ford-Smith CD. The individualized treatment of a patient with benign paroxysmal positional vertigo. Phys Ther. 1997;77:848-855.]

Key Words: Benign paroxysmal positional vertigo, Brandt/Daroff exercises, Dizziness, Vertigo.

Vertigo, the false perception of motion,l can be a debilitating and annoying impairment, causing patients to seek medical assistance.

Patients with vertigo often are referred for physical therapy without a clear differential diagnosis. Therefore, a thorough physical therapy evaluation is essential to designing an effective treatment plan.

One of the most common causes of vertigo in adults is benign paroxysmal positional vertigo (BPPV).2 Benign paroxysmal positional vertigo is defined as vertigo induced by rapid extension of the head or lateral tilt of the head toward the affected ear.2 One hypothesized cause of BPPV is "cupulolithiasis," a term coined by Schuknecht3 to describe a labyrinthine disorder that previously had been called "positional vertigo." Schuknecht's description came after postmortem histological studies of the temporal bones of two persons who previously had been diagnosed with unilateral BPPV. The examination revealed basophilic deposits on the cupula of the posterior canal (Figure) of the affected labyrinth. In most cases, the deposits are thought to be disrupted otoconia (calcium carbonate crystals) from the utricular membrane that settle on the cupula of the posterior semicircular canal.3 The deposits located on the cupula had a higher specific gravity than the specific gravity of the surrounding endolymph, creating an imbalance. Normally, the cupula and the endolymph have the same specific gravity. The deposits on the cupula create an oversensitivity of the posterior canal to angular acceleration in the plane specific to the canal.4 When the head is placed in the provoking position (eg, head extension), the cupula deflects abnormally, causing nystagmus (nonvoluntary rhythmic oscillation of the eyes5(pp115-116)), vertigo, and nausea. The latency of the onset of vertigo and nystagmus is thought to be related to the amount of time required to deflect the cupula.3 The fatigability (this sensation of vertigo diminishes and stops within 60 seconds) may be due to the dispersement of the deposits into the endolymph and a return of the cupula to its upright position. The patient, therefore, avoids the provoking position to prevent the onset of vertigo and nausea.

Benign paroxysmal positional vertigo is diagnosed based on the patient's history and the characteristic clinical findings.36 Clinical manifestations of BPPV include (1) vertigo that is induced when the patient is placed in a supine position with the head turned to one side and extended approximately 30 degrees below the horizontal, (2) vertigo that has a delayed onset of 1 to 40 seconds and that eventually stops once the patient is in the provoking position, (3) the presence of torsional nystagmus that coincides with the latency and duration of the complaint of vertigo, and (4) vertigo that rises to a plateau of intensity and then gradually decreases, subsiding within 60 seconds.6 Seventy percent of individuals experience spontaneous recovery within weeks or months. The condition, however, can persist for years, if untreated, or it can remit and recur after varying periods of time in 20% to 30% of individuals.2 About 10% of individuals with BPPV can have symptoms bilaterally, but the time of onset, duration, and intensity of symptoms can be different for each side.2

Brandt/Daroff exercises7 often are used for the treatment of BPPV.8 The exercises are based on the etiology of cupulolithiasis. The goal of this mechanical form of therapy is to dislodge and disperse the otolithic material from the cupula of the posterior canal. In 1980, Brandt and DarofU described the treatment of 67 subjects who demonstrated the classical signs and symptoms of BPPV, as described by Schuknecht.3 Subjects were 37 to 74 years of age, and symptom duration ranged from 2 days to 8 months. Each subject in the study was seated and assumed a side-lying position on the affected side until the induced vertigo ceased. The subject returned to a sitting position for 30 seconds and then assumed a side-lying position on the opposite side for 30 seconds. Subsequently, each subject repeated the positioning every 3 hours while awake and discontinued the exercises after the subject experienced 2 consecutive days of exercise without vertigo. Sixty-six of the 67 subjects were reported to be completely recovered within 3 to 14 days of initiating treatment, with absence of both vertigo and nystagmus when assuming the provoking head positions. Two of the 66 subjects experienced a recurrence after a few months that responded to a second session of positional therapy. The authors did not describe the characteristics of the reoccurrences or the time frames for each subject's symptoms to once again remit. The subjects were followed at varying intervals over a period of 3 years.

Horak and colleagues9 examined the effectiveness of three treatment approaches: an individualized vestibular rehabilitation program, a general conditioning exercise program, and a vestibular suppressant medication program. Each treatment program was administered over a period of 6 weeks. Twenty-five subjects with peripheral vestibular disorders and positional or movement-related dizziness and imbalance were randomly assigned to one of the three treatment groups. In the vestibular rehabilitation group, a physical therapist designed individual exercises to deal with each subject's particular combination of problems. The vestibular habituation exercises addressed six domains: (1) position habituation training, (2) sensory or balance retraining, (3) gaze stabilization, (4) general conditioning exercises designed to address dizziness, (5) balance and gaze stability, and (6) therapeutic intervention for secondary impairments. Subjects in all three treatment groups exhibited improvement in symptoms, with the greatest improvement being demonstrated in the vestibular rehabilitation group. The authors concluded that the individualized vestibular rehabilitation approach resulted in both improved balance and reduction in vertigo in patients with chronic peripheral vestibular disorders. The purpose of this case report is to describe the evaluation and individualized treatment, including the use of Brandt/ Daroff exercises, of a patient with vertigo who was referred for physical therapy.

Patient Description

The patient was a 32-year-old male carpenter with a complaint of dizziness or heavy-headedness. The patient reported having episodes of dizziness when lying under a cabinet with his neck extended and looking up, reaching overhead with his neck extended, looking up and extending his neck while walking down a store aisle, being awakened at night when turning over in bed, and engaging in physical exercise such as jogging. These episodes of dizziness resulted in poor job performance and occasional nights of interrupted sleep. In his description of an episode, he said that the room seemed to spin around and that he had a feeling of being off balance. He reported having this problem for 17 years, following a motorcycle accident that caused an ankle fracture. He was wearing a helmet at the time of the accident.

The patient previously had used scopolamine ear patches (Transderm Scop transdermal therapeutic system*) intermittently to relieve the symptoms of dizziness. Scopolamine is used for the prevention of nausea and vomiting related to motion sickness.10 It is administered via an adhesive disk that is placed behind the ear, over the mastoid process, several hours before a person travels. The patch is reported to be more effective if worn prior to having an episode of dizziness.9 The patient used this medication as needed, but found it to be relatively ineffective in stopping his episodes of dizziness when his neck was extended. He was taking no medication prior to or during the initial physical therapy evaluation session and had never received physical therapy for his problem. The goals of therapy were (1) for the patient to be free of dizziness when his neck was extended in a supine position or during walking and when turning over in bed and (2) for the patient to be able to resume jogging on a regular basis.

Medical Examination

Prior to being seen for physical therapy, the patient underwent an examination by the audiologist in the Department of Otolaryngology at Virginia Commonwealth University, Medical College of Virginia Campus. The patient received electronystagmography, which is a battery of tests using electrodes around the eyes to quantitatively assess vestibular function. The battery includes ocular motility testing, bithermal caloric testing, and positional testing." The test battery is capable of determining the function of the peripheral vestibular system of the left and right ears separately. Physical therapy is focused on the involved ear.

Ocular motility testing was used to identify neurological lesions. The patient was asked to follow a moving target while quantitative recordings were made of eye movements. Eye velocity and target velocity should demonstrate a 1:1 ratio. The patient demonstrated no spontaneous nystagmus, and his ocular motility was within normal limits. Electronystagmography, however, is considered to be less sensitive than direct visual inspection, so examination of eye movements during the physical therapy evaluation is an important component.5(PtI9)

During caloric testing, each ear is irrigated with warm or cool water. In the normal ear, the stimulus produces nystagmus and may produce vertigo, nausea, and vomiting; the response is absent or diminished in the involved ear. Warm irrigation of the patient's left ear produced a normal response, but there are no comparative data for the right ear. The patient refused to continue with caloric testing following initial irrigation of the left ear because he feared it would provoke his symptoms of vertigo in the right ear. A disadvantage of caloric testing is that because the test simulates only one frequency of head rotation and gives only information about the horizontal canal, the examiner is unable to infer the condition of the entire membranous labyrinth.

Positional testing was performed in five different positions while eye movements were recorded via the electrodes. The positions were sitting, right and left side lying, supine, and supine head-hanging (the patient was rapidly taken from a long sitting position to a supine position with the head rotated to the right or left side and hanging 30deg-45deg below the horizontal). The patient reported extreme dizziness in the supine position with the head turned to the right and in the head-hanging position with the head rotated to the right. The audiologist reported noting some dizziness in the left side-lying position and in the supine position with the head turned to the left, but no nystagmus occurred and dizziness was not as severe.

In summary, the patient had a normal response to caloric testing of the left ear (which would indicate that the left horizontal canal was not involved), a normal response to ocular motility testing, and an abnormal response to positional testing on the right side, with mild dizziness noted in the left ear-down position. The findings would indicate possible bilateral vestibular system involvement, but the caloric testing was incomplete.

Physical Therapy Examination

A physical therapy evaluation was performed to substantiate the diagnosis of BPPV, to determine vestibular ocular reflex (VOR) function, and to rule out loss of muscle performance or joint range of motion, which could contribute to the patient's feeling being offbalance. Bilateral gross muscle performance testing12 of the major muscle groups of the shoulders, elbows, wrists, hands, hips, knees, and ankles yielded muscle test grades of greater than fair (ie, normal limb strength). Active range of motion was within normal limits for the shoulders, elbows, wrists, hips, knees, and ankles. Eye movements were visually inspected in the vertical and horizontal directions. Smooth-pursuit eye movements13(pl58) (characterized by the ability to track a moving target with the eyes while the head is stationary) and saccadic eye movements13(plI) (characterized by the ability to rapidly redirect the line vision with the head stationary) exhibited no slowing and no spontaneous nystagmus or provoked symptoms of vertigo. Testing of the VOR in the vertical and horizontal directions produced symptoms of vertigo, with evidence of right-beating horizontal nystagmus (eye movements with a fast component to the right side and a slow component to the left side), implicating right-sided vestibular involvement. The VOR was tested by asking the patient to focus on a stationary target (such as the top of a pen) held at a distance of an arm's length from the eyes while shaking the head side to side, then up and down. The examiner observes the eye movements for accuracy (eye movements equal to head movements), speed, and nystagmus. The VOR enables an individual to maintain a steady stationary image on the retina during head movements.

Positional testing was performed using the Hallpike-Dix maneuver.14 The patient was placed in a long sitting position on the treatment table with the head turned to one side and the patient's gaze focused on the examiner's forehead. The examiner held the patient's head and rapidly moved the patient into a supine position with the head hanging 30 degrees below the horizontal. The patient was monitored for the onset latency and duration of vertigo, in addition to nystagmus that usually dissipates within 60 seconds. The vertigo and nystagmus usually coincide for both time of onset and duration after the onset. The time of onset and duration of vertigo were not recorded initially because the patient struggled to return to a sitting position immediately after the onset of his symptoms. A modified Hallpike-Dix maneuver was positive with head turning to the right and left, provoking vertigo bilaterally. Nystagmus was difficult to evaluate due to the patient's apprehension and eye blinking. The patient reported that symptoms were more severe on the right side than on the left side. A modified Hallpike-Dix maneuver was used because the patient would not allow his neck to be extended farther than approximately 10 degrees below the horizontal on each side while positioned supine.

As part of the initial evaluation, the patient received dynamic posturography on the Equitest System* in the Physical Therapy Department at the Medical College of Virginia Hospitals. The Equitest System has been extensively described in a previous publication.l5 The Equitest System has two test protocols to examine standing balance: the Sensory Organization Test (SOT) and the Motor Control Test. The SOT protocol has six sensory conditions designed to assess the patient's ability to make effective use of visual, vestibular, and proprioceptive inputs, as well as the patient's ability to suppress inaccurate sensory information required to maintain standing balance. The patient received a computergenerated SOT composite equilibrium score of 82 out of a possible 100 points. Scores near 100 indicate maintenance of upright position with no anterior or posterior excursion. When compared with the performance of age-matched controls, the patient's performance was judged to be normal. The mean composite score for individuals aged 20 to 59 years is 80.16 The patient was able to maintain a standing position in all six sensory conditions. Patients with BPPV will usually have normal equilibrium scores because their symptoms are caused by neck extension and lateral tilt of the head. During the test, the head is held in midline.

The Motor Control Test consists of a series of linear and rotational platform translations. It assesses the patient's ability to generate force, scale responses to meet the amplitude of the perturbation, and coordinate movement in standing to maintain the center of mass over the base of support. When compared with the performance of age-matched controls, the patient's performance was consistent with normal latency to response and amplitude scaling during forward and backward platform translations. During upward and downward platform rotations, he demonstrated the ability to maintain the upright position. I concluded that the patient's history, medical laboratory test findings, and physical therapy findings of a normal SOT, normal limb strength and active range of motion, abnormal response to VOR testing, and a positive Hallpike-Dix maneuver were consistent with the diagnosis of bilateral BPPV.

Course of Treatment

The patient was given a home exercise program of eye movement exercises to enhance vestibular adaptation and visual-vestibular interaction during movement of the head, along with Brandt/Daroff exercises. The patient was given eye movement exercises because of his decreased VOR response during head movements and his complaint of vertigo with physical activity. Eye movement exercises were used to increase VOR response to head movements and eliminate the onset of vertigo during head movements. The human vestibular system has the capacity to adapt to environmental changes.'7 This attribute can be accentuated to promote recovery after unilateral dysfunction by moving a target across the retina in conjunction with head movements at varied frequencies.lg Movement of a target across the retina combined with head movements results in an error signal that the brain attempts to rectify by increasing the VOR response. The eye exercises used were similar to those described by Herdman.19 The patient was asked to hold a business card at arm's length, while sitting and keeping the print in focus. He moved his head from side to side for 2 minutes without stopping and then moved his head up and down for 2 minutes. Next, to facilitate visual-vestibular interactions, the patient held a business card at arm's length while sitting and moved the card and his head from side to side in opposite directions. He repeated this activity moving his head and the card up and down in opposite directions. I emphasized to the patient that initially the home exercise program could make the frequency and intensity of his vertigo worse, but that he should not be alarmed because the symptoms would subside with continued performance. Each eye exercise was performed twice daily for 2 minutes. The frequency and duration of the exercises were based on the patient's response to the initial evaluation and his work schedule, and on previous findings that adaptation requires time (more than a few seconds each day).19

The Brandt/Daroff exercises were performed as described by Brandt and Daroff.7 The patient was asked to turn his head to the left about 45 degrees so that the lateral aspect of his occiput would rest on the mat and his chin tilted upward. That position was maintained as he lay on the right side. The position was reversed when he lay on the left side. The Brandt/Daroff exercises were performed for 5 repetitions to each side and increased to 10 repetitions as tolerated by the patient for two to five sessions daily. I decided on the initial number of repetitions in the clinic, where the patient performed repetitions until the perceived intensity of his vertigo and nausea exceeded his tolerance. The frequency and duration of the exercises were based on the patient's work schedule; he was unable to perform sessions every 3 hours while awake, as suggested by Brandt and Daroff.7

Three days after the evaluation and initiation of the home exercise program, the patient called the clinic to report that he had experienced a violent attack of vertigo during the Brandt/Daroff exercises and had been seen in the emergency department, where the physician agreed that his treatment was appropriate and prescribed 2.5 mg of Valium(R)* to be taken as needed. The patient reported that he was too scared to continue therapy, but I encouraged him to continue his home exercise program and suggested that a psychological consultation might help him develop strategies to manage his anxiety. Psychological counseling was not acceptable to the patient. The next day, he discontinued the Valium and reinitiated his home exercise program. The patient was seen for two follow-up visits, the first visit 10 days after the initial evaluation and the second visit 14 days later. Follow-up visits consisted of reassessment of eye movements and review of the Brandt/Daroff exercises. On the first follow-up visit, review of eye movements revealed no slowing or nystagmus in the horizontal and vertical directions for smooth-pursuit and saccadic eye movements. Reassessment of the VOR with head movements from side to side and up and down showed right-beating horizontal nystagmus with head movements from side to side. Vestibular ocular reflex performance with head movements up and down demonstrated no deficits. Review of Brandt/Daroff exercises revealed no vertigo in the left side-lying position after 60 seconds. With initiation of exercises in the right sidelying position, the patient had a sensation of vertigo for 1 second. He was told to continue his home exercise program until he experienced 2 consecutive days without vertigo. Eye movement exercises were to be performed in a standing position instead of a sitting position to promote the use of visual and proprioceptive cues with vestibular cues. To meet the patient's goal of jogging again, he began a walking program because he had been sedentary for more than 5 years. The program was to be done on varying surfaces (gravel, concrete, grassy areas, and a track) five times weekly for 15 to 20 minutes. He was instructed to turn his head from left to right and up and down intermittently for 1-minute intervals while walking to enhance visual-vestibular interaction with the environment during dynamic postural responses.

Twenty-four days after the initial evaluation, the patient's complaints, performance of the Hallpike-Dix maneuver, and eye movements were reassessed. He no longer had episodes of vertigo when extending his neck while lying supine or when rolling over in bed. Neck extension to view upper shelves while walking in a store did not provoke vertigo. He also reported being able to perform all aspects of his job without discomfort, such as lying under a sink with his neck extended and gazing overhead.

The Hallpike-Dix maneuver was performed to the right and left sides with no vertigo or nystagmus. The patient assumed the full head-hanging position of 30 degrees below the horizontal, to the right and left while lying supine, without resistance to assuming the position. Smooth-pursuit, saccadic, and VOR eye movements produced no symptoms of vertigo or nystagmus in a sitting or standing position. The patient was instructed to continue his walking program with head maneuvers for 3 weeks, and then to progress to walking and running five times weekly for 20 to 30 minutes on level surfaces and to discontinue the head maneuvers.

The patient was followed by phone at 1-month intervals for 3 months. One year after the initial evaluation and the start of physical therapy, the patient reported no further episodes of vertigo and a complete return to all activities without symptoms. He reported being anxious about the positions that used to make him dizzy, but symptoms were not provoked.

Discussion

After a 17-year history of positional vertigo, this patient's episodes of vertigo with neck extension were resolved after performing an individualized treatment program including Brandt/Daroff exercises. The patient also was able to begin and maintain a regular exercise program of walking and eventually could jog without provoking episodes of vertigo.

During the initial evaluation, the patient described his symptoms as dizziness, but it was clear from his description of the dizziness that he was experiencing vertigo. Dizziness is a complaint that can be associated with many diagnoses. Descriptions can range from lightheadedness to a bandlike feeling around the head.' Vertigo is the false perception of motion, with a sensation of spinning or of the environment spinning.l Vertigo is one of the identifying characteristics of BPPV, so it was important to differentiate vertigo from dizziness.

In general, patients with vertigo are more responsive to rehabilitation if they are treated during the acute onset of symptoms. Patients who are untreated often limit their daily activities, as this patient did with jogging and certain head positions, to prevent the onset of vertigo. In some cases, this limiting of daily activities can result in loss of joint range of motion in the neck, trunk, and legs; decreased job performance; and delayed recovery from vertigo. Studies using animal models suggest that a critical period exists for optimum recovery after a unilateral vestibular lesion.20 Baboons that were restrained after surgical vestibular neurotomy had prolonged recovery of postural and locomotor function when compared with baboons that were allowed to move freely in their usual environment within hours after surgery. In my experience, patients with chronic or long-standing problems will sometimes have a long rehabilitation or less than full recovery. This patient's recovery could be considered unusual in view of the functional limitations and the 17-year duration of the problem.

There are other approaches to the treatment of persons with BPPV. The single-treatment approaches (one procedure administered one time) described by Epley21 and Semont et al22 may have been just as effective in diminishing this patient's vertigo. Herdman and colleagues8 compared the effectiveness of these single-treatment approaches to determine whether they would be effective alternatives to Brandt/Daroff exercises, which were 98.5% effective in eliminating vertigo and nystagmus.7 They randomly assigned 30 subjects to each of two groups. One group received a modified Epley maneuver, and the other group received the Semont maneuver.

Seventy percent of the subjects who received the modified Epley maneuver experienced remission of their vertigo and nystagmus, and 57% of the subjects who received the Semont maneuver experienced remission of their vertigo and nystagmus. The single-treatment approaches minimize the repeated discomfort of vertigo that is felt when using Brandt/Daroff exercises; however, there are reported cases in which the single-treatment maneuver was repeated a second time to eliminate vertigo.8,21

After both the Epley and Semont approaches, the patient is required to remain upright for 48 hours and wear a soft cervical collar. The patient described in this case report was offered the option of a single-treatment approach, but he believed that the Brandt/Daroff exercises would be less offensive because while at work he would not be able to avoid bending over. The Epley approach would have required the patient to take time away from work, which was unacceptable. This approach also would have required him to assume the supine position with his neck extended, which he refused to do early in the initial evaluation. After discussing the options and modifying the frequency of the home exercise program, the patient felt confident that he could be able to carry out the program. A positive treatment outcome of this approach is dependent on the patient's ability to adhere to the program.

In conclusion, this case report illustrates a situation in which, in the presence of BPPV, an individualized treatment program using Brandt/Daroff exercises may promote recovery even after a long-standing history of problems. Theoretically, this mechanical approach is designed to dislodge the debris from the cupula of the posterior canal. If cupulolithiasis is the mechanism for BPPV, then the approach should be effective regardless of the timing of the intervention.

* CIBA Consumer Pharmaceuticals. Div of CIBA-GEIGY Corp, 581 Main St. Woodbridge, NJ 07095

^ NeuroCom International Inc, 9570 SE Lawnfield Rd, Clackamas, OP 97015.

^^ Roche Products Inc, Manati, Puerto Rico 00674.

References

I Jensen JM. Vertigo and dizziness. In: Weiner WJ, Goetz GC, eds. Neurology for the Non-neurologist. 3rd ed. Philadelphia, Pa: JB Lippincott Co; 1994:171-172.

2 Brandt TH. Vertigo: Its Multisensory Syndromes. London, England: Springer-Verlag; 1991:138-140.

3 Schuknecht HF. Cupulolithiasis. Arch Otolaryngol. 1969;90:765-779. 4 Brandt TH. Vertigo and dizziness. In: Asbury AK, McKhann GM, McDonald I, eds. Diseases of the Nervous System: Clinical Neurobiology. 2nd ed. Philadelphia, Pa: WB Saunders Co; 1992:561-576. 5 Honrubia V. Quantitative vestibular function tests and the clinical examination. In: Herdman SJ, ed. Vestibular Rehabilitation. Philadelphia, Pa: FA Davis Co; 1994:115-116, 119. 6 Herdman SJ. Assessment and management of benign paroxysmal positional vertigo. In: Herdman SJ, ed. Vestibular Rehabilitation. Philadelphia, Pa: FA Davis Co; 1994:331.

7 Brandt TH, Daroff RB. Physical therapy for benign paroxysmal positional vertigo. Arch Otolaryngol. 1980;106:484-485.

8 Herdman SJ, Tusa RJ, Zee DS, et al. Single treatment approaches to benign paroxysmal positional vertigo. Arch Otolaryngol Head Neck Surg. 1993;119:450-454.

9 Horak FB, Jones-Rycewicz C, Black 0, Shumway-Cook A. Effects of vestibular rehabilitation on dizziness and imbalance. Otolaryngol Head Neck Surg. 1992;106:175-180.

10 Physicians'Desk Reference. 47th ed. Montvale, NJ: Medical Economics Co; 1993:881-882.

I1 Carl JR. Principles and techniques of electro-oculography. In: Jacobson GP, Newman CW, Kartush JM. Handbook of Balance Function Testing. St Louis, Mo: Mosby-Year Book Inc; 1993:69-100. 12 Palmer ML. Gross muscle testing: a review. Clinical Management in Physical Therapy. 1985;5(4):18-21.

13 Leigh RJ, Zee DS. Neurology of Eye Movements. Philadelphia, Pa: FA Davis Co; 1991:110, 158.

14 Dix MR, Hallpike CS. The pathology, symptomatology, and diagnosis of certain common disorders of the vestibular system. Ann Otol Rhinol Laryngol. 1952;6:987-1016.

15 Ford-Smith CD, Wyman JF, Elswick RK, et al. Test-retest reliability of the sensory organization test in noninstitutionalized older adults. Arch Phys Med Rehabil. 1995;76:77-81.

16 Equitest Operator's Manual Version 4.0. Clackamas, Ore: NeuroCom International Inc; 1990.

17 Gauthier GM, Robinson DA. Adaptation of the human vestibuloocular reflex to magnifying lenses. Brain Res. 1975;92:331-335. 18 Herdman SJ. Exercise strategies in vestibular disorders. Ear Nose Throat J 1990;68:961-964.

19 Herdman SJ. Assessment and treatment of balance disorders in the vestibular-deficient patient. In: Balance Proceedings of the APTA Forum, Nashville, Tenn, June 13-15, 1989. Alexandria, VA: American Physical Therapy Association; 1990:87-94.

20 Lacour M, Roll JP, Appaix M. Modifications and development of spinal reflexes in the alert baboon following an unilateral vestibular neurotomy. Brain Res. 1976;113:255-269.

21 Epley J. The canalith repositioning procedure: for treatment of benign paroxysmal positional vertigo. Otolaryngol Head Neck Surg. 1992;107:399- 404.

22 Semont A, Freyss G, Vitte E. Curing the BPPV with a liberatory maneuver. Adv OtorhinolaryngoL 1988;42:290-293.

CD Ford-Smith, PT, is Assistant Professor, Department of Physical Therapy, School of Allied Health Professions, Medical College of Virginia, Virginia Commonwealth University, PO Box 980224, Richmond, VA 23298-0224 (USA) (cfordsmith@gems.vcu.edu). This article was submitted September 3, 1996, and was accepted February 24, 1997.

Copyright American Physical Therapy Association Aug 1997
Provided by ProQuest Information and Learning Company. All rights Reserved