January 2013 Dizzy Quiz Answers

Welcome to BalanceMD's first ONLINE Dizzy Quiz Answers! 

Congratulations to Dr. James Watson of American Health Network - he is the winner of the iPod Shuffle!


We have been hosting a "Dizzy Quiz" several times a year for the past four years in order to bring awareness to physicians and other healthcare providers regarding the great advances in knowledge and technology that have been made over the past two decades in the field of vestibular medicine.  We are now able to diagnose and treat conditions causing dizziness and vertigo FAR better than we could just 20 years ago.
  Below are the answers to the questions, highlighted in yellow, with explanations in green, as well as additional information about the best manner to approach the diagnosis and treatment of the "dizzy" patient.  Thank you for participating.


Betty is a 52 year old woman who reports that for the past 3 months, she has been experiencing brief spells of vertigo associated with looking up, laying down, and rolling over in bed.  She presented to her primary care physician who diagnosed her with "vertigo" and she was sent for an EKG, CBC, BMP, and TSH.  When these tests were found to be normal, Betty was given a prescription for meclizine 25 mg po tid and was told that she may just have to learn to live with vertigo.  Needless to say, her vertigo symptoms continued, the meclizine was ineffective and it caused her to be drowsy.  She presents to BalanceMD seeking a second opinion.


Recognizing that Betty's vertigo symptoms are positional in nature, we proceeded to check her for benign paroxysmal positional vertigo (BPPV).  To the right is a video demonstrating left Dix-Hallpike position in checking for BPPV and the typical upbeat rotational nystagmus that occurs.  To the far right is a VNG tracing illustrating brief right and up-beat (rotational) nystagmus in left Dix-Hallpike position.


QUESTION 1:  WHICH STATEMENT IS CORRECT?

A.  This patient is suffering from BPPV of the left posterior semicircular canal and should continue taking meclizine
B.  This patient is suffering from BPPV of the right posterior semicircular canal and should be given instructions on doing Brandt-Daroff or Cawthorne-Cooksey exercises
C.  This patient is suffering from BPPV of the left posterior semicircular canal and should undergo an Epley or Semont maneuver
D.  This patient may have a brain tumor causing her vertigo and should proceed to her nearest neuroimaging facility for an MRI of her brain
E.  This patient may have a significant carotid stenosis and should undergo a carotid ultrasound

COMMENTS:  Since Dr. John Epley published his journal article about the "canalith repositioning maneuver" treatment for BPPV, which bears his name, we have been able to cure patients suffering from BPPV instantly.  We should no longer be prescribing vestibular suppressant medications, such as meclizine, diazepam or phenergan, or having patients perform habituation exercises, such as Brandt-Daroff or Cawthorne-Cooksey.  While a brain tumor might cause "positional" vertigo symptoms, BPPV has a typical pattern of nystagmus that occurs with changes in head position, best observed in Dix-Hallpike position, which is not something that would been noted from a brain tumor.  Brain tumors are always a cause for concern, but the likelihood that a brain tumor is causing dizziness or vertigo in a patient with normal hearing and a non-focal neurologic examination is extremely small.  Statistics tell us that you would have to order 10,000 MRI scans to pick up just one brain tumor in the above scenario.  To put this in context, if you were to see one such patient (dizziness with normal hearing and non-focal neurologic examination) every day you worked (assuming 5 days/week and 50 weeks per year), and you ordered an MRI scan on each of these patients, it would take you 40 years to find that one patient.  Finally, the carotid arteries do NOT supply blood to parts of the brain involved in causing the sensation of dizziness or vertigo when blood flow is reduced.  Carotid artery TIA or stroke symptoms most commonly include transient ipsilateral monocular vision loss, contralateral hemiparesis or hemisensory loss and aphasia.  It is the vertebrobasilar circulation that would cause dizziness or vertigo with a reduction in blood flow to the brainstem, inner ear, and/or cerebellum.  For completeness, seizures are an extremely rare cause of vertigo and almost never occur in a patient without a prior history of seizures, so performing an EEG on a patient for dizziness is also an essentially worthless test.



Betty underwent a modified Epley maneuver immediately and left the office CURED of her left posterior canal BPPV.  However, after two weeks of being symptom-free, her positional vertigo symptoms returned and she presented to the office for further treatment.  Knowing her recent history of BPPV of the left posterior canal, she was placed into left Dix-Hallpike position once again and the video to the right reveals what was observed.








Hmmmm.  No nystagmus was present.  So, her recurrent positional vertigo symptoms are not due to recurrent left posterior canal BPPV.  Betty was then placed in right Dix-Hallpike position and this was also negative for BPPV.  Knowing that  BPPV can also affect the horizontal semicircular canals, Betty was then placed in supine, head right and head left position, to check for horizontal canal BPPV.  The video at the right indicates what was observed.  The VNG tracing at the far right reveals "geotropic" nystagmus (nystagmus that beats toward the ground, ie, right-beating in head right and left-beating in head left), most pronounced in head position left.





QUESTION 2:  WHICH STATEMENT IS INCORRECT?

A.  The horizontal nystagmus, worse in head left position, is characteristic of left horizontal canal BPPV
B.  Horizontal canal BPPV is not treated with an Epley maneuver, but with a Lempert, BBQ or Log Roll maneuver
C.  Horizontal canal BPPV is less common than posterior canal BPPV, representing about 15% of BPPV
D.  Betty needs to get a refill on her meclizine
E.  Treatment of horizontal canal BPPV with a Lempert roll is over 90% effective

COMMENT:  We now know that BPPV can involve not only the posterior canal (80-85%), but also the horizontal (10-15%) and anterior (1-2%) semicircular canals, and the 'canalith repositioning maneuver' for each type of BPPV is at least 90% effective in providing and instant cure.  Therefore, if the patient is reporting positional vertigo symptoms, it is important to check for "crystals" in the other semicircular canals if the Dix-Hallpike position does not reveal the upbeat rotational nystagmus that is observed with BPPV of the posterior semicircular canal.  Once again, it is always better to cure the patient of their condition, in this case BPPV, than to suppress symptoms of BPPV with medications (meclizine) that often are ineffective and have intolerable side effects.  Below is a table summarizing the various types of BPPV, with the type of nystagmus noted with what head position, and best treatment option.


 Semi-circular Canal  Head Position Nystagmus  Canalith Repositioning Maneuver 
 Posterior  Dix-Hallpike Upbeat Rotational modified Epley
 Horizontal Supine, elevated 30 deg Right-beat in head right; Left-beat in head left  Lempert Roll
 Anterioor  Dix-Hallpike Downbeat Rotational modified Epley from deep Dix-Hallpike



Thank you for participating in this activity.  I hope it has been educational.  If you have patients that would benefit from our services, please feel free to print off the "Consultation Request Form" found under the "Referring Physicians" tab.


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