It has never been entirely clear when to refer to an ENT for an asymmetric hearing loss. I understand this question may be difficult to answer specifically and answers may vary depending on the patient history and the symptoms the patient experiences. How much asymmetry is considered significant?
This excellent question has been addressed in the audiologic and medical literature for many years and indeed, there exists many referral hierarchies and cost-vs-benefit ratio analysis on this matter. Clinicians, researchers and statisticians have evaluated pure-tone average (PTA) differences across left and right ears, discrete frequency differences at particular frequencies (for example the difference between left and right thresholds at 2000 Hz), ABR differences (with respect to latencies and morphology), speech reception threshold differences, certainly word recognition scores (i.e.rollover), ipsi and contra reflex differences (elevated or absent), unilateral and even asymmetric tinnitus and more. However, to me personally, my rule of thumb is ANY unilateral or asymmetric sign or symptom is worthy of further investigation. Yes, the chances are low, yes over-referral is a real issue...but when you're a member of the "less than one percent" group, and the result is positive, it's 100 percent for you. So then, what I learned a long time ago, and what I've told students for some 25 years is anytime the test results demonstrate, or the patient reports asymmetric observations or experiences.....refer.
Dr. Beck earned his master's degree at the State University of New York at Buffalo (1984) and his doctorate from the University of Florida at Gainesville (2000). He started his career at the House Ear Institute in LA in cochlear implant research and intraoperative cranial nerve monitoring. Five years later he was Assistant Professor of Otolaryngology and the Director of Audiology at Saint Louis University. After eight years in that capacity he co-founded a private audiology-based dispensing practice in St Louis. In 1999, Dr. Beck became Editor-In-Chief of www.audiologyonline.com, www.speechpathology.com and www.healthyhearing.com. Beck joined Oticon in 2005 as Director of Professional Relations, and in 2008, he was appointed Web Content Editor for the American Academy of Audiology (AAA). Dr. Beck is a prolific author and entertaining speaker. He has addressed a wide variety of audiology and professional topics via hundreds of publications and is well known internationally for his entertaining and educational podium presentations.