Neuro-Otology

Terry D. Fife, MD

Knowledge is a process of piling up facts; wisdom lies in their simplification—Martin H. Fischer, 1879–1962

Although it can be forgotten amidst the avalanche of physician duties and requirements, it is a privilege to be a clinician entrusted with the care of other people. It can also be rewarding, especially when we can improve their lives. Dizziness, vertigo, and imbalance are very common afflictions. Our understanding and ability to ameliorate these symptoms continues to improve with scientific advances in neurobiology, diagnosis, and treatment. This issue on Neuro-Otology in Seminars in Neurology assembles a group of internationally renowned experts covering the current state of knowledge of selected disorders affecting vestibular function and equilibrium.

The issue begins with several articles on vestibular function tests. Head impulse testing is a quick, inexpensive, and noninvasive way to assess the function of each semicircular canal of each ear. Drs. Luke Chen and G. Michael Halmagyi provide a review of the current state of video head impulse testing (vHIT). Vestibular evoked myogenic potential (VEMP) testing is an established method of assessing vestibular function of the utricle and saccule and their vestibular connections. Drs. Rachael Taylor, Miriam Welgampola, Benjamin Nham, and Sally Rosengren outline the use of VEMP in vestibular localization and clinical practice. VEMP testing can reasonably assess the function of the utricle and saccule, which raises the question whether these structures may be damaged in isolation. Drs. Ian Curthoys, Ann Burgess, and Leonardo Manzari thoughtfully present the evidence for selective loss of otolith funcion. Vestibular testing by caloric, rotational chair, vHIT, and VEMP can detect and localize vestibular dysfunction. An article by Drs. Sun-Uk Lee, Hyo-Jung Kim, and Ji-Soo Kim addresses bilateral vestibular dysfunction.

Benign paroxysmal positional vertigo (BPPV) is the most common cause of recurrent vertigo. Drs. Daniele Nuti, David Zee, and Marco Mandalà provide an update on our knowledge of benign paroxysmal positional vertigo (BPPV). Acute spontaneous vertigo is also a common presentation. Dr. Kevin Kerber draws upon his expertise in acute vertigo and provides an up-to-date review on acute vestibular syndrome. Stroke and TIA are less common but very important causes of acute vertigo. Drs. Hyun Ah Kim, Hyung Lee, and Ji-Soo Kim review vertigo due to vascular mechanisms.

Vestibular migraine is a common and often under recognized and thus under-treated cause of dizziness. Dr. Robert Baloh reviews putative mechanisms and diagnostic criteria of vestibular migraine. This is followed by an article by Drs. Michael von Brevern and Thomas Lempert on treatment and prognosis of vestibular migraine despite our current lack guidance from clinical treatment trials.

We do not often think of cerebellar disorders presenting with dizziness, but it is remarkably common for patients with cerebellar ataxia to report dizziness. Drs. Andreas Zwergal, Katharina Feil, Roman Schniepp, and Michael Strupp review cerebellar dizziness and vertigo. Following this is a comprehensive review of uncommon and rare but treatable autoimmune vestibulocerebellar disorders by Drs. Ram Narayan, Andrew McKeon, and Terry Fife.

Motion sickness and visual vertigo are common in the human population, but for some patients, these can be overwhelming and intrusive symptoms. Drs. Adolfo Bronstein, John F. Golding, and Michael Gresty review visual vertigo, motion sickness, and disorientation in vehicles. Chronic dizziness with normal brain imaging and vestibular function can still be disabling for some patients. Dr. Jeffrey Staab reviews persistent postural-perceptual dizziness as one cause of such chronic dizziness.

Next, Drs. Patricia Perez-Carpena and Jose Antonio Lopez-Escamez provide a systematic review of our current understanding and clinical management of Meniere's disease. Superior canal dehiscence is a treatable anatomic disorder of the inner ear. Drs. Kristen Steenerson, Benjamin Crane, and Lloyd Minor expertly summarize our current knowledge of superior semicircular canal dehiscence syndrome. Persistent “sea legs” after departing a ship can be an uncomfortable and sometimes disabling cause of chronic dizziness for some people. Dr. Kamala Saha and Yoon-Hee Cha give an overview on Mal de Debarquement syndrome. Finally, Drs. Susan Whitney, Patrick Sparto, and Joseph Furman offer insights on vestibular rehabilitation and factors influencing patient outcome.

I greatly appreciate the contributions of these distinguished authors and thank them for their effort in disseminating their expertise in the field. I also thank Dr. David Greer, the editor-in-chief of Seminars in Neurology, for his guidance and careful review of the manuscripts. It is our hope that this issue will serve to update all clinicians to promote better health for people with dizziness, imbalance, and related symptoms.