Screening Exams

The goals of The Screening Chapter (Ch 3 in my book) are twofold: Ideally, these techniques will be learned and used at the PCP level. Using these techniques will increase the chances that a patient referred for vestibular evaluation will be an appropriate referral. I would guess that ten percent of patients sent to me clearly suffer from orthostatic hypotension, yet no one has ever checked them for this. This is a problem that can be diagnosed, and should be treated, at the PCP level. By the time they get to me, I have an obligation and a liability to make sure there is no other explanation for their symptoms. The second goal is to give Audiologists and ENTs some tools they can use if they have limited testing facilities.

Screening Exams:
You will learn much more from the patient history than you will learn from any test. You need to be skilled and patient when taking the history. I block 20 to 30 minutes per patient, and sometimes that is not enough. It is sometimes very difficult to get the patient to answer specific questions, and it can be a challenge to keep the patient on task while being pleasant at the same time. If you express frustration during the history interview, you are off to a bad start. The patient will sense (whether true or not) that you don’t have time for them, or that you must have other things to do that are more important to you than they are. Take the time. Be nice. Hang in there and get the information you need. That first 30 minutes is going to set the tone for your entire relationship with that patient.

I will often think out loud with the patient at the end of the history interview. I will tell them what I am suspecting, and what tests need to be done to confirm or rule out that suspicion. All patients are sent a handout and questionnaires before they arrive for the appointment. It describes the tests, but I will usually talk them through each test so they know why I am doing it, and what they will experience. That removes a lot of fear. (fear of the unknown, eh?)

Occasionally, you get the chance to look really smart. Some patients present with such a clear history, that there is very little doubt of the diagnosis and the tests are just confirmatory. I think the most impressive is when a patient describes a history consistent with a severe vestibular neuritis (sudden onset vertigo, nausea, vomiting, resolving over a few days; no auditory symptoms, residual motion intolerance and dysequilibrium). Typically, these patients have been admitted to the hospital for at least a few days, undergone cranial MRI, EKG, been seen by Neurology, Cardiology, and of course all tests have been negative. The patient arrives at your office a week or two later, pretty convinced that no one is going to figure out why they have been so sick. You do a Head Thrust Test ( pg 54 of my book), see an abnormal response, and tell the patient, after a 5 second exam, “It is your left ear.” The head thrust test is very specific (although not so sensitive), and you can be pretty confident that your quick diagnosis will be proven correct on additional exam.

Of course, sometimes the history is anything but clear. Another basic rule (again, not always true) is that, if after ten to fifteen minutes of questions you have no idea what is wrong with the patient, there is a very good chance that there is some psychological component. At the very least, your chances of providing a firm diagnosis at the end of the exam are very small.

A third possibility is when the patient provides a very clear description of their symptoms, you are pretty sure what is wrong, yet your tests don’t support your theory. This is the case quite often with BPPV. Read my article “Reducing False-Positive in BPPV diagnosis.”

Under other screening examinations, you will read about the Romberg and Tandem gait test. I use these two together to get an idea of whether the patients is having difficulty sensing movement (as would be the case with a vestibular disorder) or if they are having difficulty generating movement (as would be the case with a cerebellar disorder). Whenever the ENG reveals unexpected abnormalities on the ocular motor portion of the exam, I will double check for significant cerebellar dysfunction by checking for dysdiadochokinesia and abnormal tandem gait. Abnormal responses support the likelihood of cerebellar dysfunction and the need for neurological evaluation or neuro-imaging.