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C. A. Foster
must then be done from the supine position to determine whether it is apogeotropic
or geotropic [26]. There are a few simple ways to determine the affected side once
this information is obtained.
The simplest and fastest localizing clue is nystagmus intensity, which is often
more severe on one side. The nystagmus on the most intense side usually beats
toward the affected ear. In a geotropic nystagmus with the greatest response with
the right ear down, the nystagmus will beat toward the dependent right ear, which is
the affected ear. If the nystagmus is greatest with the right ear down but is apogeotropic, it will beat upward toward the left ear, and the left ear is the affected ear.
Unfortunately, the intensity of the nystagmus is not always clearly different between
sides and additional localizing methods must then be used.
The result of the initial head centered Asprella test can determine the side once
the nystagmus has been characterized as geo- or apogeotropic. For geotropic BPPV,
the nystagmus will beat away from the affected ear with the head centered. In the
apogeotropic form, it will beat toward the affected ear. The direction of the nystagmus in the “lean” (face-up) portion of the bow-and-lean test gives the same outcome.
If VNG monitoring is being used, a third method can determine the side of
involvement. There will be a null point (cessation of the nystagmus) as the head is
slowly rotated from right to left or vice versa [27]. The null point is usually found
at about 20° toward the affected side in both geotropic and apogeotropic forms
[28]. A null point that is centered or symmetric suggests that the problem maybe not
be due to BPPV.If particles obstruct the canal or ampullary neck forming a canalith
jam, a canal paresis on the affected side may be seen on caloric testing [29] and this
provides additional localizing information.
Rarely, a transient direction xed nystagmus can be seen during maneuvers for
apogeotropic H-BPPV.This unusual situation has been attributed to separate clumps
of otoconia in both the ampullary and utricular limbs of the canal moving in opposite directions during head positioning [30, 31]. Unusual mixed forms of paroxysmal nystagmus (horizontal transitioning to vertical, for example) can indicate BPPV
affecting more than one canal.
Determining the affected ear and canal is less difcult with the vertical canals.
When reux into the common crus occurs during maneuvers, particles usually pass
into the posterior canal, and the affected ear is the downward ear on Dix–Hallpike
to the symptomatic side. Entrapment is indicated when the nystagmus is unusually
persistent (greater than 1min) and many repeated maneuvers over several sessions
fail to result in improvement or resolution.
The anterior canal is oriented superiorly, so it requires rotation to a face-down
placement to cause reux, and in this position, it is difcult for the operator to detect
unless recording goggles are in use. Because free-oating particles in the utricular
arm of the canal in A-BPPV can exit when the head is returned to the upright position, patients presenting with A-BPPV typically have the type caused by ampullary
arm or trapped particles. Otoconia that pass more than halfway around the semicircular canal will fall toward the cupula instead of exiting when the patient returns to
the upright position. This allows particles to directly impact the cupula, resulting in
a continuous low-grade dizziness. The Deep Dix–Hallpike allows detection of this
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type [32]. The seated patient is placed in head hanging with the head centered. Any
particles in or near the ampulla will be displaced in this position, resulting in a ne
downbeating oblique nystagmus. The axis of ocular rotation will be in the lower
quadrant of the eye very close to one canthus, so very little torsion will be seen with
the pupil in mid-position (Fig.7.5(3)). Particles in the right anterior canal will cause
a nystagmus that beats obliquely downward and slightly toward the patient’s left,
while the left anterior canal causes a nystagmus that beats obliquely downward and
slightly toward the patient’s right [15].
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Diagnostic Dilemmas
Direction changing positional nystagmus occurs in a number of central and peripheral vestibular disorders other than BPPV.Disorders that alter the specic gravity of
the endolymph or the cupula mimic cupulolithiasis but do not respond to maneuvers. The most common form is positional alcohol-induced nystagmus (PAN),
which causes a geotropic nystagmus in its acute phase reecting alcohol uptake into
the cupula, resulting in a “light cupula.” This causes the cupulae in all six ampullae
to oat upward [33]. The reversal phase to an apogeotropic nystagmus indicates an
elevation in alcohol levels in the endolymph with respect to the cupula. This results
in a “heavy cupula” relative to endolymph that reverses the nystagmus direction as
the cupulae sink downward in the direction of gravity. PAN is easily differentiated
from BPPV by the acute history of alcohol intoxication and its disappearance over
the course of several hours.
Acute vestibulopathies can also result in light cupula [34]. A brisk spontaneous
nystagmus beating away from the affected ear is often found in these cases. The
positional and spontaneous nystagmus resolves over the course of several days, in
contrast to cupulolithiasis which can persist for months. As in PAN, light cupula can
result either from any process that lowers specic gravity in the cupula or that raises
the specic gravity in endolymph [35].
Heavy cupula is at present thought to be primarily due to cupulolithiasis but can
also occur if endolymph specic gravity is lowered or in canalith jam near the
ampulla. Cupulolithiasis usually involves only one semicircular canal, so the presence of both horizontal and vertical direction changing positional nystagmus indicates a more widespread aural or central problem.
Management
BPPV can be quickly relieved by removing the particles from the semicircular
canals. Many maneuver variations have been devised to achieve this goal. It may
require repeated maneuvers in a single session to completely clear all particles from
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the affected canal. All maneuvers rotate the head in the plane of the treated canal,
but it is also necessary to rotate the entire body in order to achieve this.
Most patients do not require medication to suppress the vertigo during maneuvers. For patients with intractable vomiting during maneuvers, meclizine, benzodiazepines, and antiemetics can make the patient more comfortable. These can also be
given for motion-sensitive patients who wish to do maneuvers at home.
C. A. Foster
Maneuvers forthePosterior Canal
For classic P-BPPV, the Epley maneuver is the most efcacious for clinic use with
a success rate after repeated maneuvers exceeding 90% [21]. Most patients are
cleared after 1–3 maneuvers. The diagnostic test, the Dix–Hallpike maneuver, is the
rst step in the maneuver and moves particles about halfway toward the exit. The
patient is then rolled to the opposite shoulder. After pausing to allow further gravitymediated movement of particles, the patient is moved to the sitting position during
which the particles exit the canal (Fig.7.6).
The Epley maneuver has several advantages over other maneuvers for clinic use.
First, by incorporating the diagnostic test as the rst movement, the clinician can
see the nystagmus and conrm the location of particles, while simultaneously and
efciently moving them toward the exit. Second, it is designed to move the particles
continuously toward the canal exit using both gravity and uid motion, while other
maneuvers may slosh particles back and forth. Disadvantages are that after a successful maneuver, repeating the Dix–Hallpike can cause reux of newly removed
particles into the common crus or horizontal canal [15]. This can be mitigated by
waiting 15min between maneuvers. It also causes substantial vertigo and nausea
because the particles are moving swiftly in the most stimulatory direction. This
means that an assistant is usually required to help restrain the patient on the table
and move them as needed.
The Semont maneuver is also effective for P-BPPV, although there is less evidence supporting it than for the Epley maneuver [36]. The patient is seated on the
exam table facing the examiner. A variation of the Dix–Hallpike is performed, with
the patient moved onto one side instead of supine, ending with the head in typical
Dix–Hallpike position, face up, chin elevated and rotated 45° toward the shoulder
on the unaffected side. This allows identication of P-BPPV and begins movement
of the particles toward the exit. The patient is then raised to the upright position
maintaining the 45° rotation of the head toward the shoulder. Without pause, movement continues until the opposite shoulder is down on the table (Fig.7.7). The head
will then be turned facing the oor at a 45° angle. The patient is then raised to the
upright seated position.
The advantages of the Semont maneuver are that the sideways Dix–Hallpike
variation is as effective as the supine maneuver incorporated into the Epley maneuver for diagnosis and initial movement of particles. It can also be done without an
assistant because the patient remains facing the examiner on one side of the table,
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Fig. 7.6 Epley maneuver, right ear. The Dix–Hallpike is performed, followed by rotation of the
head through 180°. The patient is then moved upright. (With permission from Foster
CA.Overcoming Positional Vertigo. Boulder, CO: Bull Publishing; 2019)
while the Epley requires rotating the patient lengthwise to face the opposite side of
the table. However, there are disadvantages. After the diagnostic Dix–Hallpike, the
next steps of the Semont maneuver raise the head of the patient, which allows some
particles to slosh back toward the ampulla rather than continuing toward the utricle
as in the Epley maneuver. Having the head then placed face down increases the risk
of reux into the anterior canal. Like the Epley maneuver, it also carries a similar
risk of reux into the posterior or horizontal canals because it incorporates a form
of the Dix–Hallpike maneuver.
These and other maneuvers have been advocated for home use but carry a risk of
canal conversion to H-BPPV because of the included Dix–Hallpike maneuver. The
Dix–Hallpike maneuver is designed to maximize nystagmus so it is easily visible to
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Fig. 7.7 Semont maneuver, right ear. The seated patient is reclined with the head turned to the left
at 45°, away from the tested right ear. After reclining with the right shoulder down (left side of
gure) the head is in typical Dix–Hallpike position. Keeping the head turned 45° to the left, the
patient is then raised back to the seated position and reclined on the left shoulder, head now facing
downward at 45° to the oor (right side of gure). (With permission from Foster CA.Overcoming
Positional Vertigo. Boulder, CO: Bull Publishing; 2019)
C. A. Foster
Fig. 7.8 Half somersault maneuver, left ear. Positions are held for 30s or until the sensation of
vertigo ceases. (1) The kneeling patient rocks the head and body back until facing the ceiling. (2)
The head is placed upside down on the oor. (3) The head is rotated 45° to face the left elbow. (4)
The head is quickly raised to back/shoulder level. The patient should view the left elbow to keep
the head at 45° from the midline. (5) The head is kept turned left and is raised fully upright as the
patient returns to the kneeling position. If the right ear is being treated, the head is turned toward
the right elbow in steps (3)–(5). (With permission from Foster CA.Overcoming Positional Vertigo.
Boulder, CO: Bull Publishing; 2019)
the clinical examiner, but at home an examiner is not present and maximizing nystagmus also maximizes the experience of vertigo and so is counterproductive. The
half somersault maneuver was devised as a home exercise to reduce the risk of
H-BPPV while still clearing particles [37] (Fig.7.8). It does not include the Dix–
Hallpike, reducing overall vertigo and the risk of canal conversion. In addition, an
assistant is not required. The patient tips the head upward to move particles away
from the ampulla, and then places the head upside down on the oor. Particles are
drawn through the canal by gravity alone. The head is then rotated 45° to place the
posterior canal in the sagittal plane. The head is then rotated upward in two stages
until the head is upright. This rotates the particles out using uid motion and gravity.
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While it avoids canal conversion and reduces vertigo, it may require more repetitions than the Epley maneuver (four on average) to completely clear the canal.
If particles become entrapped in the posterior canal ampulla, a very persistent
torsional, upbeating nystagmus is seen when supine or on Dix–Hallpike that reverses
to a ne downbeating nystagmus when seated with the head facing down and to the
affected side [24]. This may require many maneuvers to dislodge. Placing the
patient in the Dix–Hallpike head position and vibrating the head can sometimes
dislodge the particles, resulting in a burst of typical P-BPPV.An Epley maneuver
can then be used to remove the particles from the canal.
Maneuvers fortheHorizontal Canal
When H-BPPV occurs during treatment of the posterior canal, the onset of horizontal nystagmus on Dix–Hallpike indicates that particles are reuxing by gravity into
the horizontal canal. Returning the patient to upright as soon as horizontal nystagmus is identied stops further reux. Any particles remaining in the horizontal canal
can then be removed in a few simple steps. In the Gufoni maneuver, the supine
patient is raised upright to face the examiner, then reclined on the opposite side with
the shoulder down, head rotated slightly upward [38] (Fig.7.9). The head is then
rotated smoothly to face the table. Since this maneuver incorporates raising the
patient to upright, it is the best maneuver to stop and correct reux. Usually only
one maneuver is required. It can be performed without an assistant.
Patients with pre-existing, free-oating H-BPPV will usually present with geotropic H-BPPV. Identifying the side of involvement is important as noted in the
prior section. The Gufoni maneuver is highly effective for pre-existing H-BPPV.
The log roll maneuver has been used for many years for H-BPPV [39]. The
supine patient is rolled away from the affected ear, moving the particles with both
gravity and uid motion toward the vestibule. It is necessary to perform a 360°
Fig. 7.9 Gufoni maneuver, right ear. The patient is seated facing the operator. Positions are held
for 30s. (1) While upright, the head is turned 45° to the right. (2) Move the patient onto their left
side. (3) Rotate the head left toward the table. (4) Return the patient to the upright position, keeping
the head turned toward the left. (With permission from Foster CA.Overcoming Positional Vertigo.
Boulder, CO: Bull Publishing; 2019)
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rotation of the body to complete the maneuver. This type of rotation is somewhat
difcult to perform on a narrow exam table and requires an assistant. An exercise
mat on the oor can be used for log roll treatment and a mat is also useful during
any maneuver for morbidly obese patients who cannot be treated safely on an
exam table.
The Vannucchi–Asprella maneuver is a simple alternative to the log roll that
reduces the need to rotate the entire body [40]. The patient is placed supine, and the
head is next turned 90° away from the affected ear. The patient is then raised to the
seated position. This is usually sufcient to remove particles from the horizontal canal.
A disadvantage of maneuvers for free-oating particles in the horizontal canal is
that performing maneuvers for the incorrect ear can lead to conversion to the much
more serious ampullary arm or entrapped forms including cupulolithiasis and canalith jam. All maneuvers are designed to rotate the head away from the affected ear,
moving the particles toward the utricle. If a patient is accidentally rotated toward
the affected ear, particles are moved deeper toward the ampulla where they can
lodge. Determining the affected ear can be confusing and lead to this mistake.
Fortunately, most cases of H-BPPV occur during maneuvers, and the affected ear is
always the ear with P-BPPV that is undergoing treatment. The Gufoni maneuver
immediately stops reux by raising the patient upright and the design of the maneuver ensures that the correct ear is being treated.
The apogeotropic form of H-BPPV indicates that particles are in or very near the
ampulla, where they can be entrapped (lodging within the ampulla or attached to the
cupula, as in cupulolithiasis). Maneuvers have a lower success rate for this form of
H-BPPV.Due to the enhanced sensitivity of the horizontal canal, nystagmus can be
extremely severe, and vomiting may limit maneuvers. The affected side should rst
be determined. Horizontal head shaking on the upright patient can help dislodge
particles from the ampulla, followed by the maneuvers above [41]. As in the posterior canal form, vibration can be used to move particles from the ampulla. The
patient is placed supine with the head elevated 30° and turned 20–45° toward the
affected ear. Vibration is then applied to the mastoid. Repeated quick horizontal
head rotations while supine can also be used to dislodge particles. If the particles are
recalcitrant to ofce maneuvers, patients can do these exercises at home. Once converted to the geotropic forms, indicating that the particles have move to the utricular
arm, the maneuvers above resolve the problem.
C. A. Foster
Maneuvers fortheAnterior Canal
Because common crus reux brought on by Dix–Hallpike reverses when the
patient’s head is returned to upright, only the cases with entrapped particles in or
near the ampulla are usually seen by a physician. An oblique and downbeating nystagmus on Dix–Hallpike indicates that particles are in the ampulla of the anterior
canal. Because anterior canal particles are often entrapped, maneuvers are less
effective than for the free-oating forms seen in the other canals. The Deep
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Dix–Hallpike is the simplest maneuver [32] (Fig.7.10). The patient is placed supine
with the neck hyperextended off the table so that the top of the head points toward
the oor. If particles can exit the ampulla, they will move about halfway toward the
canal exit in this position. The patient’s head is then raised in two steps, rst to a
semireclined position and then to a face-forward and down position, allowing particles to exit. In the Yacovino and Hain version, the head is centered so both anterior
canals are treated simultaneously, although neither canal will be exactly in the plane
of head rotation. In another version using head dependency, the head is turned away
from the affected ear to place it in the plane of head rotation, and the patient is
moved to a supine position and then the body is raised upright with the head and
chin tipped downward [42]. Performing an Epley maneuver from the opposite
(unaffected) side has also been used. Unfortunately, the success rate in resolving
A-BPPV is lower than for other forms. This is likely to be due to entrapment of
particles in the ampulla or at the common crus. Placing the patient in the deep Dix–
Hallpike position and then applying vibration for several minutes can result in an
abrupt release of particles from their entrapment, after which completing the maneuver resolves the BPPV.Patients can also do the deep Dix–Hallpike repeatedly as a
home exercise.
Prognosis
While most patients achieve a complete resolution of dizziness with maneuvers, the
condition is recurrent. Home exercises should be taught to reduce the need for ongoing clinical care. People who are too frail to perform home exercises may require
repeated clinic visits and should be taught how to avoid reux. Lying at on the
back or inverting the head increases the risk of recurrence, and avoidance of these
positions may allow these patients to reduce the frequency of spells [43].
Fig. 7.10 Deep Dix–Hallpike maneuver for both anterior canals. Each position should be held for
30–60s. (1) The patient is moved to the head-hanging position with the head centered. (2) The
patient’s head and torso are elevated until facing forward and upward. (3) The patient is moved
forward to face the knees. (With permission from Foster CA.Overcoming Positional Vertigo.
Boulder, CO: Bull Publishing; 2019)
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C. A. Foster
Surgery
Surgery should be reserved for frequently recurrent or entrapped forms that cannot
be resolved or controlled with maneuvers. Canal-plugging is highly effective [44].
It can be used for all three canal forms [45, 46]. Relief from vertigo is immediate,
but the procedure disables the canal, so there can be some residual dizziness as
compensation to the loss occurs. Rarely, ablative procedures can be used if multiple
canals are involved in one ear and attacks are very frequent.
Controversies
The original description of Epley’s maneuver included slow rotation of the head
along with continuous mastoid vibration to move the particles while causing minimal nystagmus. This was felt to be more comfortable for patients, who experienced
little vertigo during treatment [7]. Later practitioners found that rotating the head
quickly without vibration was equally effective, although the vertigo is more intense.
The use of vibration during maneuvers became unpopular after a study showed both
forms of treatment had similar 1week and long term outcomes after three maneuvers [32], and a Cochrane review recommended against its use [47]. Otoconial
masses are sticky and can become lodged during maneuvers. This is likely to occur
when particles are entrapped in or near the ampulla, such as during apogeotropic
H-BPPV and with cupulolithiasis or canalith jam. Vibration is likely to be helpful
when this occurs [48]. During the Dix–Hallpike maneuver, some patients show no
nystagmus until vibration is applied, which allows adherent particles to mobilize.
No studies comparing Dix–Hallpike with and without vibration have yet been
performed.
Requiring patients to maintain an elevated head position or wear a soft collar as
a head elevation reminder for a few days after maneuvers was advocated by early
practitioners of maneuvers. Keeping the head elevated prevents an immediate recurrence in the rst days after treatment. Many subsequent studies showed that future
long-term recurrences were not affected by short-term head position restrictions
[47]. Since there is a risk of particle reux every time the head is placed in a dependent position, head positioning restrictions would need to be used continuously to
prevent future recurrence. This is not needed for most patients who will have only
occasional recurrences.
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