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eMedicine = Specialties >=20 Emergency = Medicine=20 > Neuro= logy

Benign Positional Vertigo

Author: Andrew K Chang, = MD,=20 Associate Professor, Department of Emergency Medicine, Albert Einstein = College=20 of Medicine, Montefiore Medical Center
Contributo= r=20 Information and Disclosures

Updated: Aug 24, 2009

Print=20 This
Email=20 This

Overview
Different= ial=20 Diagnoses & Workup
Treatment= =20 & Medication
Follow-up<= /A>
Multimedia

References
Keywords

Introduction

Background

Benign positional vertigo (BPV) is the most common cause of vertigo. = Vertigo=20 is an illusion of motion (an illusion is a misperception of a real = stimulus) and=20 represents a disorder of the vestibular proprioceptive system.

BPV was first described by Adler in 1897 and then by B=E1r=E1ny in = 1922; however,=20 Dix and Hallpike did not coin the term benign paroxysmal positional=20 vertigo until 1952. This terminology defined the characteristics of = the=20 vertigo and introduced the classic provocative test that is still used = today.=20 Using positional testing, benign positional vertigo can readily be = diagnosed in=20 the emergency department. Benign positional vertigo is one of the few = neurologic=20 entities the emergency physician can cure at the patient's bedside by = performing=20 a series of simple and safe head-hanging maneuvers.

For further=20 information, see Benign = Positional=20 Vertigo in the Neurology volume.

Pathophysiology

Benign positional vertigo (BPV) is caused by calcium carbonate = particles=20 called otoliths (or otoconia) that are inappropriately displaced into = the=20 semicircular canals of the vestibular labyrinth of the inner ear. These = otoliths=20 are normally attached to hair cells on a membrane inside the utricle and = saccule. Because the otoliths are denser than the surrounding = endolymph,=20 changes in head movement vertically causes the otoliths to tilt the hair = cells,=20 which triggers a nerve that send a signal to the brain letting the brain = know=20 that the head is tilting up or down.

The utricle is connected to the 3 semicircular canals. The otoliths = may=20 become displaced from the utricle by aging, head trauma, or labyrinthine = disease. When this occurs, the otoliths have the potential to enter the=20 semicircular canals. When they do, they almost always enter the = posterior=20 semicircular canal because this is the most dependent (inferior) of the = 3=20 canals.

Anatomy of the semicircular canals.

[ CLOSE = WINDOW ]

Anatomy of the semicircular=20 canals.

According to the=20 canalolithiasis theory (the most widely accepted theory of the = pathophysiology=20 of benign positional vertigo), the otoliths are free-floating within the = canal.=20 Changing head position causes the otoliths to move through the canal. = Endolymph=20 is dragged along with the movement of the otoliths, and this stimulates = the hair=20 cells of the cupula of the affected semicircular canal, causing vertigo. = When=20 the otoliths stop moving, the endolymph also stops moving and the hair = cells=20 return to their baseline position, thus terminating the vertigo and = nystagmus.=20 Reversing the head maneuver causes the particles to move in the opposite = direction, producing nystagmus in the same axis but reversed in = direction of=20 rotation. The patient may describe that the room is now spinning in the = opposite=20 direction. When repeating the head maneuvers, the otoliths tend to = become=20 dispersed and thus are progressively less effective in producing the = vertigo and=20 nystagmus (hence, the concept of fatigability).

Frequency

United States

The incidence of benign positional vertigo (BPV) is 64 cases per = 100,000=20 population per year (conservative estimate).^{1 =}

International

One study in Japan found an incidence of 11 cases per 100,000 = population per=20 year, but patients were counted only if examined by a subspecialist or = at a=20 referral center.

Mortality/Morbidity

The B of BPV stands for benign and designates that = the=20 cause of the vertigo is peripheral to the brainstem and, hence, likely = to be=20 benign. However, BPV can be severely incapacitating to the=20 patient.

Sex

Women are affected twice as often as men.

Age

BPV, in general, is a disease of elderly persons, although onset can = occur at=20 any age. Several large studies show an average age of onset in the mid = 50s.=20 Vertigo in young patients is more likely to be caused by labyrinthitis=20 (associated with hearing loss) or vestibular neuronitis (normal = hearing).

Clinical

History

When asked about their dizziness, patients with benign positional = vertigo=20 (BPV) characteristically describe that the room or world is spinning. = However,=20 other descriptions, such as rocking, tilting, somersaulting, and the = like, are=20 also possible. All that matters is that an illusion of motion is caused = by a=20 misperception of a stimulus (the otoliths). Diagnosis of BPV is based on = a=20 characteristic history and a positive Hallpike test.

Episodic vertigo may occur with the following head movements:
- Rolling over in bed
- Lying down
- Sitting up
- Leaning forward
- Turning the head in a horizontal plane
Symptoms of BPV are usually worse in the morning (the otoliths are = more=20 likely to clump together as the patient sleeps and exert a greater = effect when=20 the patient gets up in the morning) and mitigate as the day progresses = (the=20 otoliths become more dispersed with head movement).
Nausea is typically present (vomiting is less common).
A history of head trauma may be present, especially in young = patients with=20 BPV. The head trauma may dislodge the otoliths off the hair = cells within=20 the utricle, allowing them the opportunity to enter the semicircular = canals.
Eliciting that the individual episodes of vertigo in BPV last for = seconds=20 at a time is important. Patients may describe that they are having = continuous=20 vertigo, when in reality, they are having repeated episodes (with each = episode=20 typically lasting seconds or less than a minute). Patients with = vestibular= =20 neuritis and labyrinthi= tis=20 have continuous vertigo, often for hours to days.
During the interview, if patient states that the "room is=20 spinning" while the patient's head is still and prior to any = manipulative=20 tests, then it is highly unlikely that the patient has BPV = because the=20 vertigo in BPV lasts for seconds at a time and occurs only after head=20 movement.

Physical

In addition to the patient's history, a diagnosis of = benign=20 positional vertigo (BPV) is confirmed by a positive Hallpike = test.^{2,3 =}In this=20 test, the patient is placed in the head-hanging position after turning = the head=20 to the side. After a short delay of a few seconds, nystagmus and = reproduction of=20 the vertigo occurs and typically resolves within 30-60 seconds. The = neurologic=20 examination is otherwise unremarkable.

Nystagmus= =20 (an involuntary rhythmic oscillation of the eyes) is described in = terms of the=20 fast-phase component.
- Classic nystagmus occurs when the patient's head is dependent = and turned=20 to the affected side.
- The nystagmus is torsional or rotatory. In the head-hanging = position,=20 the fast phase should beat toward the forehead (upbeat) and in the = same=20 direction as the affected side (ipsilateral). Although some describe = the=20 fast phase in terms of being clockwise or counterclockwise, most = experts=20 avoid this terminology because it can be unclear if the clock is = being=20 viewed from the patient's or physician's perspective.
- Nystagmus usually occurs within 10 seconds after positioning but = may=20 present as late as 40 seconds. Hence, if the history is classic, = observe the=20 patient for at least 40 seconds while he or she is in the = head-hanging=20 position during the Hallpike test.
- Duration varies from a few seconds to a minute and parallels the = sensation of vertigo.
- Response fatigues if the patient is repeatedly placed into the = provoking=20 position (due to dispersion of the otoliths).
Note: If the patient has a classic history of BPV (after a short = delay,=20 the room spins, but then revolves in 20-30 seconds, and then the rooms = spins=20 in the opposite direction when he or she sits back up) but no = nystagmus is=20 seen during the Hallpike test, most experts would agree to go ahead = and treat=20 the patient with the modified Epley maneuver (see
Treatment).
- Nystagmus may be blocked by fixation suppression. Most emergency = physicians do not have access to Frenzel lenses or infrared = nystagmography=20 that specialists use to prevent fixation suppression.
- One study showed that treating such patients with the Epley = maneuver is=20 still effective (despite the lack of nystagmus). Again, these = patients must=20 have a classic history.
Perform the Hallpike test as follows (Caution: For patients with = cervical=20 spondylosis, it may not be advisable to extend the neck. However, = because=20 having the head dependent is important, the same effect can be = achieved if the=20 gurney is placed in the Trendelenburg position for such patients).
- First, warn the patient that symptoms of vertigo will likely be=20 reproduced but will resolve after a few seconds.
- Seat the patient close enough to the end of the gurney so that = when he=20 or she lies supine, the head can extend backward an additional = 30-45=B0.
- Instruct the patient to keep his or her eyes open because you = want to=20 observe the direction of the nystagmus. The examiner may need to use = his=20 thumb to hold the eyelid open because patients may involuntarily = close their=20 eyes even when instructed to keep them open.
- To test the left posterior canal, follow these steps:
  - Turn the patient's head 45=B0 to the left. This position = orients the=20 head such that the left posterior semicircular canal is going to = be in the=20 same plane as the upcoming head movement (next step). This is the = most=20 provocative way to move the otoliths (if they are indeed in the = posterior=20 semicircular canal) which will result in a positive test.
  - With your hands on either side of the patient's head, lay the = patient=20 down until the head is dependent (hanging over the edge of the = gurney).=20 Note that this step does not need to be performed rapidly.
  - Check for reproduction of symptoms and nystagmus. In most = cases, the=20 fast phase of the nystagmus should be upbeat (toward the forehead) = and=20 ipsilateral (in this example, toward the patient's left).
  - Return the patient to the upright position. Nystagmus may be = observed=20 in the opposite direction, and the patient may describe that the = world is=20 spinning in the opposite direction.
- To test the right posterior canal, repeat the Hallpike test with = the=20 head turned 45=B0 to the right side. In general, if the patient has = BPV, only=20 one side should test positive during the Hallpike test. Although = having=20 bilateral posterior semicircular canal BPV is possible, it is = unlikely and=20 should suggest horizontal canal involvement, vestibular=20 neuritis/labyrinthitis, or a central cause.
- Note that almost all patients experience mild dizziness when = being=20 brought up from the head-hanging position to the sitting position. = It is=20 important not to confuse this dizziness (which is more near-syncope = in=20 character) with true vertigo.
If the patient's head cannot be extended over the edge of the = gurney, 2=20 additional options exist. The first is to place the patient in the=20 Trendelenburg position if a gurney that allows this position is = available. The=20 other alternative is to use the side-lying test; the patient sits with = his or=20 her legs over one side of the gurney. To test the left posterior = semicircular=20 canal, turn the patient's head 90=B0 to the opposite side (in this = case, the=20 right side). Then, lay the patient on his or her left side. By turning = the=20 patient's head to the right, the left posterior semicircular canal is = aligned=20 in the same plane as the sideways movement. As in the Hallpike test, = this will=20 allow the greatest chance for otoliths to move if they are indeed = located in=20 the posterior semicircular canal.
The neurologic examination findings should be otherwise normal; if = not,=20 strongly consider alternative diagnoses.

Causes

Several disorders affecting the peripheral vestibular system may = precede the=20 onset of benign positional vertigo (BPV).

Idiopathic (50-60%)
Infection (viral neuronitis)
Head trauma, especially in younger patients
Degeneration of the peripheral end organ
Surgical damage to the labyrinth

References

Froehling DA, Silverstein MD, Mohr DN, Beatty CW, Offord KP, = Ballard=20 DJ. Benign positional vertigo: incidence and prognosis in a=20 population-based study in Olmsted County, Minnesota. Mayo Clin = Proc. Jun 1991;66(6):596-601. [Medline].<= /P>
[Guideline] Bhattacharyya N, Baugh RF, Orvidas L, Barrs D, Bronston = LJ,=20 Cass S, et al. Clinical practice guideline: benign paroxysmal = positional=20 vertigo. Otolaryngol Head Neck = Surg. Nov 2008;139(5=20 Suppl 4):S47-81. [Medline].= [Full Text].
Furman JM, Cass SP. Benign paroxysmal positional = vertigo. N=20 Engl J Med. Nov 18 1999;341(21):1590-6. [Medline].=
[Guideline] Fife TD, Iverson DJ, Lempert T, Furman JM, Baloh RW, = Tusa RJ,=20 et al. Practice parameter: therapies for benign paroxysmal = positional=20 vertigo (an evidence-based review): report of the Quality Standards=20 Subcommittee of the American Academy of=20 Neurology. Neurology. May=20 27 2008;70(22):2067-74. [Medline].= [Full Text].
Epley JM. Particle repositioning for benign paroxysmal = positional=20 vertigo. Otolaryngol Clin North=20 Am. Apr 1996;29(2):323-31. [Medline].<= /P>
Baloh RW. Dizziness and vertigo. In: Samuels MA, Feske=20 S. Office Practice of = Neurology. London: Churchill=20 Livingstone; 1996:83-91.
Brandt T, Daroff RB. Physical therapy for benign paroxysmal = positional=20 vertigo. Arch=20 Otolaryngol. Aug 1980;106(8):484-5. [Medline].<= /P>
Chang AK, Schoeman G, Hill M. A randomized clinical trial to = assess=20 the efficacy of the Epley maneuver in the treatment of acute benign = positional=20 vertigo. Acad Emerg = Med. Sep 2004;11(9):918-24. [Medline].=
Froehling DA, Bowen JM, Mohr DN, et al. The canalith = repositioning=20 procedure for the treatment of benign paroxysmal positional vertigo: a = randomized controlled trial. Mayo Clin=20 Proc. Jul 2000;75(7):695-700. [Medline].=
Lempert T, Gresty MA, Bronstein AM. Benign positional vertigo: = recognition and treatment. BMJ. Aug=20 19 1995;311(7003):489-91. [Medline].<= /P>
Marill KA, Walsh MJ, Nelson BK. Intravenous Lorazepam versus=20 dimenhydrinate for treatment of vertigo in the emergency department: a = randomized clinical trial. Ann Emerg=20 Med. Oct 2000;36(4):310-9. [Medline].=
Massoud EA, Ireland DJ. Post-treatment instructions in the = nonsurgical=20 management of benign paroxysmal positional vertigo. J=20 Otolaryngol. Apr 1996;25(2):121-5. [Medline].<= /P>
Troost BT, Patton JM. Exercise therapy for positional=20 = vertigo. Neurology. Aug 1992;42(8):1441-4. [Medline].<= /P>

[ CLOSE = WINDOW=20 ]

Keywords

benign positional vertigo, benign = paroxysmal=20 positional vertigo, BPV, = vertigo, dizziness= ,=20 dizziness symptoms, dizziness treatment, inner ear, Hallpike test, Epley = maneuver, lightheade= dness,=20 canalolithiasis theory, otoliths,= Brandt=20 exercise, Daroff exercise

near-synco= pe,=20 dysequilibriu= m,=20 disequilibrium, orthostat= ic=20 hypotension, vasovagal = episode, neurocardi= ogenic=20 syncope, disorder = of=20 thevestibular proprioceptive system, labyrinthi= tis,=20 vestibular= =20 neuronitis, nystagmus= ,=20 torsional nystagmus, rotatory nystagmus, dizzy= ,=20 head-hanging maneuvers, labyrinthine = disease, otoconia,= =20 psychophysiologic dizziness

[ CLOSE = WINDOW=20 ]

Contributor Information and Disclosures

Author

Andrew K Chang, MD, Associate Professor, = Department of=20 Emergency Medicine, Albert Einstein College of Medicine, Montefiore = Medical=20 Center
Andrew K Chang, MD is a member of the following medical = societies: American Academy of = Emergency=20 Medicine, American=20 Academy of Neurology, American College of Emergency Physicians, and Society for Academic = Emergency=20 Medicine
Disclosure: Nothing to disclose.

Medical Editor

Edward Bessman, MD, Chairman, Department of = Emergency=20 Medicine, John Hopkins Bayview Medical Center; Assistant Professor, = Department=20 of Emergency Medicine, Johns Hopkins University
Edward Bessman, MD is = a=20 member of the following medical societies: American Academy of Emergency Medicine, American College = of Emergency=20 Physicians, and Society for=20 Academic Emergency Medicine
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior = Pharmacy=20 Editor, eMedicine
Disclosure: = eMedicine Salary Employment

Managing Editor

J Stephen Huff, MD, Associate Professor, = Emergency=20 Medicine and Neurology, Department of Emergency Medicine, University of = Virginia=20 Health Sciences Center
J Stephen Huff, MD is a member of the = following=20 medical societies: American Academy=20 of Emergency Medicine, American Academy of Neurology, American College = of Emergency=20 Physicians, and Society for=20 Academic Emergency Medicine
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of=20 Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; = Chief=20 Information Officer, CareGroup Healthcare System and Harvard Medical = School;=20 Attending Physician, Division of Emergency Medicine, Beth Israel = Deaconess=20 Medical Center
John D Halamka, MD, MS is a member of the following = medical=20 societies: American=20 College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic = Emergency=20 Medicine
Disclosure: Nothing to disclose.

Chief Editor

Rick Kulkarni, MD, Assistant Professor of = Surgery,=20 Section of Emergency Medicine, Yale-New Haven Hospital
Rick Kulkarni, = MD is a=20 member of the following medical societies: Alpha Omega = Alpha, American Academy of = Emergency=20 Medicine, American=20 College of Emergency Physicians, American Medical Association, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic = Emergency=20 Medicine
Disclosure:=20 WebMD Salary Employment

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If a function is provided it will be invoked = upon successful * completion of the submit and will be passed the response from the = server. * If an options Object is provided, the following attributes are = supported: * * target: Identifies the element(s) in the page to be updated with = the server response. * This value may be specified as a jQuery selection string, = a jQuery object, * or a DOM element. * default value: null * * url: URL to which the form data will be submitted. * default value: value of form's 'action' attribute * * type: The method in which the form data should be submitted, = 'GET' or 'POST'. * default value: value of form's 'method' attribute (or = 'GET' if none found) * * beforeSubmit: Callback method to be invoked before the form is = submitted. * default value: null * * success: Callback method to be invoked after the form has been = successfully submitted * and the response has been returned from the server * default value: null * * dataType: Expected dataType of the response. One of: null, 'xml', = 'script', or 'json' * default value: null * * semantic: Boolean flag indicating whether data must be submitted in = semantic order (slower). * default value: false * * resetForm: Boolean flag indicating whether the form should be reset = if the submit is successful * * clearForm: Boolean flag indicating whether the form should be = cleared if the submit is successful * * * The 'beforeSubmit' callback can be provided as a hook for running = pre-submit logic or for * validating the form data. If the 'beforeSubmit' callback returns = false then the form will * not be submitted. The 'beforeSubmit' callback is invoked with three = arguments: the form data * in array format, the jQuery object, and the options object passed = into ajaxSubmit. * The form data array takes the following form: * * [ { name: 'username', value: 'jresig' }, { name: 'password', = value: 'secret' } ] * * If a 'success' callback method is provided it is invoked after the = response has been returned * from the server. It is passed the responseText or responseXML value = (depending on dataType). * See jQuery.ajax for further details. * * * The dataType option provides a means for specifying how the server = response should be handled. * This maps directly to the jQuery.httpData method. The following = values are supported: * * 'xml': if dataType =3D=3D 'xml' the server response is = treated as XML and the 'after' * callback method, if specified, will be passed the = responseXML value * 'json': if dataType =3D=3D 'json' the server response will be = evaluted and passed to * the 'after' callback, if specified * 'script': if dataType =3D=3D 'script' the server response is = evaluated in the global context * * * Note that it does not make sense to use both the 'target' and = 'dataType' options. If both * are provided the target will be ignored. * * The semantic argument can be used to force form serialization in = semantic order. * This is normally true anyway, unless the form contains input elements = of type=3D'image'. * If your form must be submitted with name/value pairs in semantic = order and your form * contains an input of type=3D'image" then pass true for this arg, = otherwise pass false * (or nothing) to avoid the overhead for this logic. * * * When used on its own, ajaxSubmit() is typically bound to a form's = submit event like this: * * $("#form-id").submit(function() { * $(this).ajaxSubmit(options); * return false; // cancel conventional submit * }); * * When using ajaxForm(), however, this is done for you. * * @example * $('#myForm').ajaxSubmit(function(data) { * alert('Form submit succeeded! Server returned: ' + data); * }); * @desc Submit form and alert server response * * * @example * var options =3D { * target: '#myTargetDiv' * }; * $('#myForm').ajaxSubmit(options); * @desc Submit form and update page element with server response * * * @example * var options =3D { * success: function(responseText) { * alert(responseText); * } * }; * $('#myForm').ajaxSubmit(options); * @desc Submit form and alert the server response * * * @example * var options =3D { * beforeSubmit: function(formArray, jqForm) { * if (formArray.length =3D=3D 0) { * alert('Please enter data.'); * return false; * } * } * }; * $('#myForm').ajaxSubmit(options); * @desc Pre-submit validation which aborts the submit operation if form = data is empty * * * @example * var options =3D { * url: myJsonUrl.php, * dataType: 'json', * success: function(data) { * // 'data' is an object representing the the evaluated json = data * } * }; * $('#myForm').ajaxSubmit(options); * @desc json data returned and evaluated * * * @example * var options =3D { * url: myXmlUrl.php, * dataType: 'xml', * success: function(responseXML) { * // responseXML is XML document object * var data =3D $('myElement', responseXML).text(); * } * }; * $('#myForm').ajaxSubmit(options); * @desc XML data returned from server * * * @example * var options =3D { * resetForm: true * }; * $('#myForm').ajaxSubmit(options); * @desc submit form and reset it if successful * * @example * $('#myForm).submit(function() { * $(this).ajaxSubmit(); * return false; * }); * @desc Bind form's submit event to use ajaxSubmit * * * @name ajaxSubmit * @type jQuery * @param options object literal containing options which control the = form submission process * @cat Plugins/Form * @return jQuery * @see formToArray * @see ajaxForm * @see $.ajax * @author jQuery Community */ jQuery.fn.ajaxSubmit =3D function(options) { if (typeof options =3D=3D 'function') options =3D { success: options }; options =3D jQuery.extend({ url: this.attr('action') || window.location, type: this.attr('method') || 'GET' }, options || {}); var a =3D this.formToArray(options.semantic); // give pre-submit callback an opportunity to abort the submit if (options.beforeSubmit && options.beforeSubmit(a, this, options) = =3D=3D=3D false) return this; // fire vetoable 'validate' event var veto =3D {}; jQuery.event.trigger('form.submit.validate', [a, this, options, = veto]); if (veto.veto) return this; var q =3D jQuery.param(a);//.replace(/%20/g,'+'); if (options.type.toUpperCase() =3D=3D 'GET') { options.url +=3D (options.url.indexOf('?') >=3D 0 ? '&' : '?') + = q; options.data =3D null; // data is null for 'get' } else options.data =3D q; // data is the query string for 'post' var $form =3D this, callbacks =3D []; if (options.resetForm) callbacks.push(function() { = $form.resetForm(); }); if (options.clearForm) callbacks.push(function() { = $form.clearForm(); }); // perform a load on the target only if dataType is not provided if (!options.dataType && options.target) { var oldSuccess =3D options.success || function(){}; callbacks.push(function(data, status) { jQuery(options.target).attr("innerHTML", = data).evalScripts().each(oldSuccess, [data, status]); }); } else if (options.success) callbacks.push(options.success); options.success =3D function(data, status) { for (var i=3D0, max=3Dcallbacks.length; i < max; i++) callbacks[i](data, status); }; // are there files to upload? var files =3D jQuery('input:file', this).fieldValue(); var found =3D false; for (var j=3D0; j < files.length; j++) if (files[j])=20 found =3D true; if (options.iframe || found) // options.iframe allows user to force = iframe mode fileUpload(); else jQuery.ajax(options); // fire 'notify' event jQuery.event.trigger('form.submit.notify', [this, options]); return this; // private function for handling file uploads (hat tip to YAHOO!) function fileUpload() { var form =3D $form[0]; var opts =3D jQuery.extend({}, jQuery.ajaxSettings, options); =20 var id =3D 'jqFormIO' + jQuery.fn.ajaxSubmit.counter++; var $io =3D jQuery('