Benign Paroxysmal Positional Vertigo: Pearls for diagnosis

A 68 yo patient presents with a complaint of having developed sudden onset of dizziness, the evening before, after turning in bed. The whole room was spinning. It was exacerbated by turning his head to the left. The patient was able to get up out of bed and move around, however became very dizzy. The symptoms had not resolved in the morning, so an ambulance was called.

By the time the patient arrives in the emergency department, all symptoms have resolved. Examination shows a well patient with normal vital signs. heart sounds are dual and chest and abdominal examinations are normal. The neurological examination including cranial nerves,  cerebellar signs and nystagmus are also normal.

1. Can we make the diagnosis based on these findings?
2. What should we do now?
3. Is there a place for the Dix-Hallpike manoeuvre in this patient?
4. Does the patient need a CT Brain?

Benign paroxysmal positional vertigo (BPPV) has a cumulative life incidence of 10%, so the chances are that we will have already seen, and will see several patients presenting with BPPV. Studies have shown that only a small group of patients that are seen with BPPV have a Dix-Hallpike manoeuvre(DHM) performed on them, however approximately 30% will have a brain CT performed, with low yield(1, 2). I believe that one aspect that causes confusion, is that these patients may present with no nystagmus, when the symptoms have mostly resolved and that can lead us to perform low yield diagnostic tests or manoeuvres.

How does BPPV present?

BPPV is usually a sudden onset of brief vertigo, which lasts for only a few minutes. It is caused by particular head movements, such as looking up or down, or rolling over in, or getting out of bed. The occurrence of symptoms at nighttime whilst in bed, have been associated with a high likelihood ratio for BPPV. (3-5)

Although the acute episode may be short-lived, there is a possibility that patients will have a reduced level of ‘dizziness’ that continues to linger. If the vertigo is constant, the differentials  include vestibular neuronitis and a posterior circulation stroke.

What is often confusing to us, is that patients with a diagnosis of vestibular neuronitis or stroke, may sometimes feel better with the head in certain positions, or  by keeping their head still.

Mimics of BPPV and Presentations that suggest other causes

• Patients with BPPV should not have gaze evoked nystagmus, if they do, then consider a diagnosis of vestibular neuronitis or stroke.
• Acute headache
• Diplopia
• Any neurological findings, including cranial nerve  and cerebellar findings.
• Abnormal nystagmus
  • Persistent nystagmus that is downbeating, seesaw, rotational or bidirectional
  • Nystagmus with no dizziness
  • Bilateral Nystagmus

Making the Diagnosis

In most cases a rapid onset, short history, and associated events such as moving the head suddenly exacerbating symptoms, can assist with the diagnosis. The DHM is an essential part of the examination.

Things to note about the DHM

• If it reproduces dizziness on one side, but not nystagmus:
  • This may be due to less otoliths in the canal
  • It can be due to incorrect DHM technique, where the patient is lowered too slowly and/or the head is not tilted back by 20 degrees.
• If it reproduces dizziness bilaterally without nystagmus:
  • The BPPV may have resolved spontaneously, or there are a reduced number of otoliths in the canal.
  • There is another cause of the
• The DHM should be used on patients who:
  • do not have other obvious medical causes
  • do not have an abnormal neurological examination
  • do not have spontaneous or gaze-evoked nystagmus. An important pitfall is to diagnose BPPV in patients who cannot walk independently; this would be rare in BPPV and another diagnosis should be sought. Moreover, discharging a patient who newly cannot walk is usually unsafe, whatever the cause.

The Epley Manoeuvre

The Epley manoeuvre can be used in patients with a positive DHM. When used in the appropriate patients,  it is very effective with number needed to treat of 3 (8). One of the key parts of this manoeuvre is to lower the head rapidly enough, to not allow redistribution of the otoliths. The speed used, is just a little faster than the patient would lay their head down on the bed.

What causes BPPV?

Otoliths which are embedded in the membrane of the utricle and the saccule can dislodge and float in the endolymph. If they enter one of three  semicircular canals, they move with head movement, affecting the flow of endolymph and resulting in the nystagmus we often see. There are three variants of BPPV dependent on which canal the otolith enters:

• Posterior semicircular canal
  • Most common
  • Longer duration of symptoms (average of 39 days)(6)
  • The DHM will produce transient upbeating and torsional nystagmus
• Horizontal semicircular canal
  • Less common
  • Symptoms can last about a week (7)
  • The supine head roll (head turned to either side ) test will result in a triggered response on both sides, but more pronounced on the affected side.
    • The nystagmus will be horizontal, but can beat either towards the ceiling or the floor, depending on the position of the otolith.
  • Anterior semicircular canal
    • Rare
    • Resolves rapidly
    • The DHM will result in transient downbeating horizontal nystagmus

References

1. Kerber KA, et al. Use of BPPV processes in emergency department dizziness presentations: a population- based study. Otolaryngol Head Neck Surg. 2013;148(3):425-430.
2. Polensek SH, Tusa R. Unnecessary diagnostic tests often obtained for benign paroxysmal positional vertigo. Med Sci Monit 2009;15(7):MT89-94, MT94.
3. Lindell E, et al. Asking about dizziness when turning in bed predicts examination findings for benign paroxysmal positional vertigo. J Vestib Res J Vestibul Res-Equil. 2018;28(3–4):339-347.
4. Lindell E, et al. Investigation of self-reported dizziness in the elderly when lying down or turning over in bed, and possible benign paroxysmal posi- tional vertigo. J Laryngol Otol. 2019;133(4):275-280.
5. van Dam VS, et al. Two symptoms strongly suggest benign paroxysmal positional vertigo in a dizzy patient. Front Neurol. 2020;11:625776.
6. Imai T, et al. Natural course of the remission of vertigo in patients with benign paroxysmal positional vertigo. Neurology. 2005;64(5):920-921.
7. Shim DB, et al. Natural history of horizontal canal benign paroxysmal positional vertigo is truly short. J Neurol. 2015;262(1):74-80.
8. Hilton M, Pinder D. The Epley (canalith repositioning) manoeuvre for benign paroxysmal positional vertigo. Cochrane Database Syst Rev. 2014;12(8):CD003162.
9. Edlow J A, et al. Benign Paroxysmal vertigo: A practical approach for emergency physicians. Acad Emerg Med 2023;30:570-588