Repeat Positional Testing - Are You Willing To Risk It For The Biscuit?

Mar 11, 2023

A recent Instagram post caught my eye as it indicated that given a particular study, clinicians should not repeat positional testing after performing a canalith repositioning technique for BPPV. The reason for this, I believe, was due to the risk of causing the loose otoconia to fall right back into one of the canals.

To be honest this post surprised me. I just assumed that it was common practice now-a-days to repeat positional testing to see the effect of treatment. Don’t we want to evaluate the effect of our treatment? Then, when I went back to find that post and hopefully get the study they were referring to, it was buried deep in the social media abyss.

I was a bit disappointed that I could not find that post, but to be honest I agree and disagree with the post. Let me tell you why.

My journey with repeat positional testing

I was first taught the canalith repositioning techniques in the early 2000's. Back then I was never instructed to retest the effect of treatment in the same session. I was, however, instructed to clear for VBI first, use vibration, and give strict (temporary) activity restrictions.

Along the journey I changed my approach with all of these given our understanding of BPPV. Specifically, I started to perform repeat positional testing on the same session.

Benefits of Repeat Positional Testing

With immediate repeat testing I found that I was able to:

Confirm if I cleared the canal. If not, as long as the patient was doing well, I could repeat the treatment. I think the most times that I have repeated a canalith repositioning technique in one session was eight. Usually patients either got better before then, turned a bit green so I stopped and booked them in in the next day or two, or I ran out of time. If I ran out of time I sometimes showed them how to perform the maneuver on their own. I then instructed them to do it daily until they were either 100% or they saw me for their next appointment, whichever came first.
Rule out canal conversion, which according to Bhattacharyya in the clinical practice guidelines occurs 6-7% of the time. Interestingly, the Friday after I saw that social media post I had a patient come in with BPPV affecting the posterior canal. I performed the modified Epley maneuver and repeated the Dix-Hallpike test which revealed lateral conversion. Now, did the treatment or the repeat Dix-Hallpike cause the conversion, who knows? Regardless, left untreated before a long weekend was not ideal. Fortunately, I recognized the conversion and was able to utilize the BBQ Roll.

Bottom line is, why not get our patients as good as we can in the first visit? With one treatment maneuver we may potentially only get a portion of the otoconia out of the canal. Or, the maneuver in some cases can cause canal conversion that should be addressed.

Of note, the 2017 clinical practice guidelines for BPPV also confirm that there is a demonstrated beneficial effect of multiple treatment maneuvers, during the initial appointment, for patients with persistent nystagmus following the initial maneuver.

Cons of Repeat Positional Testing

As indicated previously there is the risk of the test causing the loose otoconia to fall right back into a canal. This is noted in a 2012 study. The study, however, states, “If the first CRP clears the posterior canal, there is an elevated risk of reentry or canal conversion if another Dix-Hallpike is performed immediately. These complications can be treated by additional maneuvers …”. This study goes on and does not say not to retest, but rather that if you do not know how to treat lateral canal BPPV do not repeat the Dix-Hallpike test for at least 15 minutes.

Hack to Address the Risk

Remember that I initially stated that I agreed and disagreed with the social media post. I agree that repeat positional testing increases the risk of otoconia falling back into a canal. On the other hand, I do not agree that we should not retest for the reasons outlined above. To mitigate the risk I always finish off with a canalith repositioning maneuver, just incase, even if testing is negative.

Some Other Things to Consider

I am disappointed that I was not able to track down that article on Instagram as I wanted to see what the strength of the recommendations were based on sample size and other factors in the study design.

Regardless, if we want to be evidence based let’s take a practical approach to research. We should look at what a study brings to the table with what research has already shown. In this case, this study in question brought to light the risk for repeat testing causing BPPV. BUT, with complementing the assessment with repeat treatment we can be reassured that our patient can go home with less of a risk with sleeping on their affected side. Remember that the evidence shows that post treatment instructions are not routinely required. So, why should we avoid repeat testing when we can let patients go home and lay on their affected side?

If you are looking for more evidence for the benefits of repeat testing here are 4 articles:

Are You Going To Risk It For the Biscuit?

With reading through this I hope that it provides you with a practical and evidence based approach that will improve your confidence and outcomes.

If you have any questions or comments, it would be great to hear from you. Learning from each other always makes everyone better. Kregg can be reached at [email protected].

Finally, have you ever wondered where the term “risk it for the biscuit” came from? No, it was not Jimmy Fallon playing Truth or truth?, but you can click HERE to find out its roots.