What is Benign Paroxysmal Positional Vertigo? Benign Paroxysmal Positional Vertigo (BPPV) is a condition in which a patient has brief, sometimes severe attacks of rotatory vertigo with and without nausea, which are caused by rapid changes in head position relative to gravity. Typical triggers of BPPV include lying down or sitting up in bed, turning around in bed, getting in and out of bed and also bending over to tie the shoelaces, or extending the head in order to look up. Patients suffering from BPPV can be treated with certain well established exercises/maneuvers and relief is obtained in ninety percent of such cases in a week’s time.
What is pathophysiology of BPPV? The Otoliths become detached from hair cells in utricle, inappropriately and most commonly enter the posterior semicircular canal owing to its gravity dependent position. In the normal situation as one turns head, for example, to the right the endolymph moves and SCC receptors fire. The nerve impulses generated in the vestibular nerve reach the vestibular nuclei and through medial longitudinal fasciculus impulses reach the subnuclei of oculomotor nerves carrying the information that "head is turning to the right". These oculomotor subnuclei turn the eyes in the same plane to the same degree but in the opposite direction so that the target of fixation falls on fovea. When the head stops turning, the endolymph stops moving and the SCC receptors stop firing and previously generated nerve impulses in the vestibular nerve cease. This information also reaches through the vestibular nuclei and medial longitudinal fasciculus to the subnuclei of oculomotor nerves informing that "head has stopped turning to right" so that the corrective eye movements induced as a consequence of disruptive head movements stop.In BPPV even after the head has stopped moving, the otoliths keep moving and drag the endolymph. As a result the receptors continue to fire inappropriately giving a false information to the oculomotor subnuclei that "head is still moving". Since the eyes know that “head is not moving”, this leads to visual-vestibular mismatch and this is interpreted by the brain as “surrounding must be spinning in the opposite direction.
”What is cupulithiasis? In 1962, Dr Harold Schuknecht proposed the cupulolithiasis (heavy cupula) theory. Via photomicrographs, he discovered basophilic particles or densities that were adherent to the cupula. He postulated that the PSC was rendered sensitive to gravity by these abnormal dense particles attached to, or impinging on, the cupula. This is analogous to the situation of a heavy object attached to the top of a pole. The extra weight makes the pole unstable and thus harder to keep in the neutral position. This produces persistent nystagmus and also explains the dizziness when a patient tilts the head backward.
What is canalithiasis theory? In 1980 Epley published his canalithiasis theory. He believed that the symptoms of BPPV were more consistent with free-moving densities (canaliths) in the PSC rather than fixed densities attached to the cupula. While the head is upright, the particles sit in the PSC at the most gravity-dependent position. When the head is tilted back supine, the particles are rotated up to about 90 degrees along the arc of the PSC. After a momentary (inertial) lag, gravity pulls the particles down the arc. This causes the endolymph to flow away from the ampulla and causes the cupula to be deflected. The cupular deflection produces nystagmus.
What is Epley maneuver?
The Epley maneuver (also called canalith repositioning procedure or CRP) is a technique which is used to treat benign paroxysmal positional vertigo (BPPV). The maneuver consists of moving the patient through a series of positions which are designed to dislodge the debris (also called canaliths or otoconia made up of calcium carbonate) that has inappropriately entered the semicircular canal (mostly posterior semicircular canal) to the utricle where they are normally present in the form of calcium carbonate. In around 70% of cases, the Epley maneuver is very effective and the patient may require no further follow up treatment. Epley maneuver may be carried out by a doctor or a physical therapist and even by the patient himself. The diagnosis of BPPV is established on the basis of clinical history and Dix-Hallpike test (also called Nylen Barany test). It is important to lateralize the disorder to right or left and to localize it to the involved canal (posterior/anterior/horizontal) which can be done most of the times with the help of performing the Dix-Hallpike testing and observing the positional nystagmus. In most of the cases by practice, the treating doctor is able to lateralize the side (left or right) and localize the involved canal by observing the nystagmus elicited by Dix-Hallpike testing.
How is Dix-Hallpike testing done and what is expected to be seen and interpreted?
The video below shows Dix-Hallpike testing done by Dr. Ajay Kumar Vats, D.M. (Neurology), Udaipur, Rajasthan on a patient with left posterior semicircular canal BPPV, which is the most common variant of positional vertigo. This elicits an ageotropic upbeat nystagmus in the Hallpike position (diseased ear undermost).How is Dix-Hallpike testing done and what is expected to be seen and interpreted?
What are contraindications of Epley maneuver?
Rheumatoid arthritis with atlanto-axial instability, severe degenerative cervical spinal disease including atlanto-axial instability from any cause, high grade carotid stenosis, unstable heart disease, ongoing CNS disease (TIA/stroke) and pregnancy beyond 24 weeks are contraindications to Epley maneuver.
Who should be doing Epley maneuver? Ideally it should be done by the doctor (or a physical therapist in supervision of the treating doctor) who has diagnosed BPPV, and has lateralized as well as localized the involved semicircular canal. If the treating doctor is satisfied with the fact that the patient will be able to correctly perform the Epley maneuver self, this can be taught to the patient who can do it.
Is a single time Epley maneuver enough? According to one study (Gustavo Polacow Korn et al.Repeated Epley’s maneuver in the same session in benign positional paroxysmal vertigo.Brazilian Journal of Otorhinolaryngology 2007; 73 (4): 533-539) repeated Epley maneuvers in less sessions rendered more positional nystagmus-free patients when compared to those submitted to more sessions of single maneuvers.
What is Semont maneuver? The Semont maneuver (also called the Liberatory maneuver or brisk treatment) is effective in get ridding of the symptoms of benign paroxysmal positional vertigo (BPPV) with a cure rate of 53% after one treatment and 76% to 90% after two treatments in patients with canalithiasis. The Semont maneuver involves the patient rapidly moved from lying on one side to lying on the other. A single 10 - 15 minute session is usually all that is required. The Semont maneuver is performed as per the following five steps: 1. The patient is asked to sit on a sturdy examination couch in such a way that his both lower limbs are dangling down the free edge of the couch and the treating doctor (or the physical therapist) is on the other side of the couch so that the back of the patient is towards the front of the doctor (or the physical therapist).2. In this position the patient’s head is turned 45 degrees horizontally towards the unaffected ear.3. The patient’s torso with the patient’s head is turned 45 degrees horizontally toward the unaffected ear is tilted to 105 degrees so that he is lying on the side of the affected ear with his head hanging and nose pointed upwards. Patient remains in this position for around 3 minutes - allowing debris to move to the apex of the ear canal.4. The patient is then quickly moved from this tilted half supine position, holding patient’s head in place to the opposite side through a 180 degree sweep until he is lying on the side of the unaffected ear with his nose pointed towards the ground. Patient remains in this position for 3 minutes allowing the debris to move toward the common crus.5. The patient is then slowly lifted back to the seated position. The debris/otoconia is presumed to fall into the utricle of the canal with this where it will no longer causes recurrent positional vertigo although a very severe vertigo with retropulsion often occurs when the patient is lifted to sit. The latter usually signifies a successful repositioning of the otoconia.
What is Brandt-Daroff treatment? This form of treatment, invented by Professor Thomas Brandt and Professor Robert B. Daroff is a series of repetitive exercises. The patient sits on a bed in such a way that his both lower limbs are dangling down the free edge of the bed. The patient turns his head 45° horizontally to one side and then rapidly lies to the opposite side. The patient remains in this position for about 20 seconds and then slowly sits up and waits for 20 seconds. The same movement with same head positioning is repeated on the opposite side. The whole sequence is done five times in each direction and is performed one to three times a day for up to two weeks. The exercises are continued till the patient has two consecutive days without any symptoms. The purpose of this treatment is to move the otoconia/debris in the SCC back and forth. The individual otoconia particles dissolve in the endolymph in hundred hours as per the studies carried out in the guinea pigs. Brandt-Daroff treatment is, therefore, believed to work by breaking up the otoconia to allow its dissolution rather than repositioning the otoconia in the utricle. Brandt-Daroff treatment is the optimal treatment for mild canalithiasis of the posterior or anterior SCC. This situation occurs when the patient still has symptoms but no signs of BPPV (absence of inducible nystagmus on the Dix-Hallpike testing) after a single treatment. This treatment can be used in patients with severe BPPV caused by canalithiasis or cupulolithiasis, but it is not the first choice because it causes vertigo during the maneuver and may takes up to two weeks for success.
What are the recommendations of report of the quality standards subcommittee of the American Academy of Neurology (AAN) on the practice parameters for the optimal treatment of posterior semicircular canal BPPV?
Canalith repositioning procedure has been established as an effective and safe therapy that should be offered to patients of all ages with posterior semicircular canal BPPV. Recommendations have been rated as Level A as per the published Class I studies. The Semont maneuver is possibly effective for PSCCBPPV but receives only a Level C recommendation based on a single Class II study. There are many experts who believe that the Semont maneuver is as effective as canalith repositioning procedure, based on currently published articles but according to AAN practice parameters committee, the Semont maneuver can only be classified as “possibly effective.” There is insufficient evidence to establish the relative efficacy of the Semont maneuver to CRP (Level U).
What is horizontal canal BPPV? The posterior semicircular canal owing to its gravity dependent position is the most commonly affected canal as the otoconia have the ease to enter this canal when the patient lies down. This is the reason why the posterior semicircular canal BPPV is the most common form accounting for approximately 85 to 90% of the cases of BPPV. Therefore unless otherwise qualified BPPV refers to posterior canal BPPV with the side (right or left) specifically lateralized. However 5 to 10% of patients of BPPV as per the different series of published scientific data have the horizontal canal BPPV.The Pagnini-McClure maneuver (also called the supine head turn maneuver or Roll test) is used to elicit the horizontal nystagmus. In this, the head is quickly rolled to one side, and nystagmus is looked for and the patient is asked to report any vertigo. The head is then slowly rolled back to a supine position. The head is then quickly rolled to the other side, and nystagmus is looked for and the patient is asked to report any vertigo. Whether it is canalithiasis or cupulolithiasis, the patient would have nystagmus and vertigo when they are rolled to either side but the type of nystagmus would differ in these two types of BPPV. For canalithiasis, the nystagmus is transient and the direction of the quick phases is toward the earth (geotropic). This is because the cupula bends up as the otoconia moves through the SCC, which transiently increases the firing rate in the nerve from horizontal SCC. For cupulolithiasis, the nystagmus is sustained and the direction of the quick phases is away from earth (ageotropic). This is because the cupula bends down caused by the weight of the otoconia, which causes a sustained decrease in the firing rate in the nerve from the horizontal SCC. Thus a horizontal canal BPPV also has two variants- a canalithiasis caused variant and another cupulithiasis caused variant.Barbeque roll over maneuver or Lempert’s maneuver has been found to be an optimal form of treatment is for severe forms of horizontal SCC BPPV caused by canalithiasis. It can be used as an alternative treatment for horizontal SCC BPPV caused by mild canalithiasis. In the Barbeque roll over maneuver, the patient lies on his or her back on the examination bed with the affected ear down (the affected ear is being identified as the side that causes the most nystagmus and vertigo during the roll test.) The patient's head is then slowly rolled away from the affected ear until the nose is pointing up; the patient stays in this position for about 15 seconds or until the dizziness stops, whichever is more. The patient then continues to rolls the head in the same direction until the affected ear is up and remains in that position for 15 seconds or until the dizziness stops whichever is more. The patient then rolls the head and body in the same direction until the nose is down and remains there for 15 seconds. Finally, the head and body are rolled in the same direction to the original position with the affected ear down. After 15 seconds the patient then slowly sits up keeping his or her head level or pitched down 30°. The Barbeque roll over maneuver is more or less same for canalithiasis or cupulithiasis variant of the horizontal canal BPPV but each head turn is performed as quickly as possible in the latter variant as per some authorities in this subject.The video below shows Bar-be-que roll over maneuver or Lempert's maneuver being performed by Dr. Ajay Kumar Vats, D.M. (Neurology), Udaipur (Rajasthan), on a patient with left horizontal semicircular canal BPPV, which is a relatively uncommon form of positional vertigo. This elicits an ageotropic horizontal nystagmus in the first position (i.e.the fast component of nystagmus away from earth with the diseased ear undermost). This patient had a closed head trauma three days prior to complaints of vertigo. The first position of this maneuver is equivalent to Pagnini-McClure maneuver (also called the supine head turn maneuver or Roll test). The Bar-be-que 360 degree roll over maneuver or Lempert's maneuver performed in this patient coincides with reversal of ageotropic horizontal nystagmus in the first position (i.e. the fast component of nystagmus away from earth with the diseased ear undermost) to geotropic horizontal nystagmus in the fifth position (i.e. the fast component of nystagmus towards the earth with the diseased ear undermost), disappearance of vertigo and successful repositioning of otoconial particles from horizontal canal to the utriculus.
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