When nystagmus is observed post head shake, can the side of peripheral lesion be determined based on the direction of nystagmus observed? Are there typical abnormal response patterns? What treatments or additional tests would be indicated when an abnormal response is observed?
Answer
Post head-shaking nystagmus (HSN) is induced by oscillating the head at high frequency in the horizontal plane, as when you shake your head to indicate a "No" response. This test is used in the clinic to detect the presence of a unilateral loss of vestibular function.
There have been two distinct types of HSN in the horizontal plane reported: monophasic with fast-phase direction towards either side, or biphasic with the direction of fast phases reversing after a few seconds. Peripheral vestibular loss of function intensifies existing non-linearities in the vestibular system, so that imposed oscillations of the head can induce biases which are the source of HSN.
Clinical and research observations demonstrate that the sign and amplitude of the bias is variable and does not lateralize the lesioned side, unless high head velocities are imposed. This explains why the direction of the initial phase of HSN in the clinic seems so prone to error. Subsequent monophasic or biphasic characteristics of HSN are simply the reflection of interactions between two main time constants associated with "velocity storage" and "gaze holding" in the vestibular central processes.
Other tests that might be helpful would be tests that measure VOR gain, such as the Vorteq, or possibly tests that help in identifying oscillopsia, such as the Dynamic Visual Acuity Test.
Henry P. Trahan, Au.D., is Assistant Professor of Audiology at the Arizona School of Health Sciences.
Henry Trahan, MCD
Related Courses
1https://www.audiologyonline.com/audiology-ceus/course/vestibular-schwannoma-medical-and-surgical-36879Vestibular Schwannoma: Medical and Surgical Evaluation and ManagementThis course reviews the common symptoms and findings associated with vestibular schwannoma, as well as workup and differential diagnosis for lesions of the cerebellopontine angle. A discussion of the natural history of vestibular schwannoma and general current paradigms for treatment are included.auditory, textual, visual129USDSubscriptionUnlimited COURSE Access for $129/yearOnlineOnlyAudiologyOnlinewww.audiologyonline.comVestibular Schwannoma: Medical and Surgical Evaluation and ManagementThis course reviews the common symptoms and findings associated with vestibular schwannoma, as well as workup and differential diagnosis for lesions of the cerebellopontine angle. A discussion of the natural history of vestibular schwannoma and general current paradigms for treatment are included.36879OnlinePT60M
This course reviews the common symptoms and findings associated with vestibular schwannoma, as well as workup and differential diagnosis for lesions of the cerebellopontine angle. A discussion of the natural history of vestibular schwannoma and general current paradigms for treatment are included.
2https://www.audiologyonline.com/audiology-ceus/course/vestibular-schwannoma-comprehensive-evaluation-management-36901Vestibular Schwannoma: Comprehensive Evaluation, Management, and Intraoperative MonitoringExperienced providers from Michigan Medicine will detail the patient journey from identification through intervention for vestibular schwannomas. This series will provide an overview of diagnostic auditory and vestibular evaluations relevant to vestibular schwannomas, medical and surgical management of these tumors from the perspective of a neurotologist, as well as intraoperative monitoring considerations.auditory, textual, visual129USDSubscriptionUnlimited COURSE Access for $129/yearOnlineOnlyAudiologyOnlinewww.audiologyonline.comVestibular Schwannoma: Comprehensive Evaluation, Management, and Intraoperative MonitoringExperienced providers from Michigan Medicine will detail the patient journey from identification through intervention for vestibular schwannomas. This series will provide an overview of diagnostic auditory and vestibular evaluations relevant to vestibular schwannomas, medical and surgical management of these tumors from the perspective of a neurotologist, as well as intraoperative monitoring considerations.36901OnlinePT180M
Experienced providers from Michigan Medicine will detail the patient journey from identification through intervention for vestibular schwannomas. This series will provide an overview of diagnostic auditory and vestibular evaluations relevant to vestibular schwannomas, medical and surgical management of these tumors from the perspective of a neurotologist, as well as intraoperative monitoring considerations.
3https://www.audiologyonline.com/audiology-ceus/course/vestibular-migraine-in-children-most-41033Vestibular Migraine in Children: The Most Common Cause of DizzinessVestibular migraine is the most common cause of dizziness in children, yet often underdiagnosed due to challenges in symptom reporting and the lack of objective biomarkers. This course explores the clinical presentation, pathophysiology, diagnostic approach, and multidisciplinary management strategies of vestibular migraine in the pediatric population.auditory, textual, visual129USDSubscriptionUnlimited COURSE Access for $129/yearOnlineOnlyAudiologyOnlinewww.audiologyonline.comVestibular Migraine in Children: The Most Common Cause of DizzinessVestibular migraine is the most common cause of dizziness in children, yet often underdiagnosed due to challenges in symptom reporting and the lack of objective biomarkers. This course explores the clinical presentation, pathophysiology, diagnostic approach, and multidisciplinary management strategies of vestibular migraine in the pediatric population.41033OnlinePT90M
Vestibular migraine is the most common cause of dizziness in children, yet often underdiagnosed due to challenges in symptom reporting and the lack of objective biomarkers. This course explores the clinical presentation, pathophysiology, diagnostic approach, and multidisciplinary management strategies of vestibular migraine in the pediatric population.
4https://www.audiologyonline.com/audiology-ceus/course/neurotology-for-audiologists-39015Neurotology for AudiologistsThis course discusses various otologic diseases and how audiologists can participate in the care.auditory, textual, visual129USDSubscriptionUnlimited COURSE Access for $129/yearOnlineOnlyAudiologyOnlinewww.audiologyonline.comNeurotology for AudiologistsThis course discusses various otologic diseases and how audiologists can participate in the care.39015OnlinePT60M
5https://www.audiologyonline.com/audiology-ceus/course/vestibular-care-for-diabetic-patients-37736Vestibular Care for Diabetic PatientsVestibular dysfunction and significant fall risks are more prevalent in the diabetic population. Learn about the pathophysiology and epidemiology of diabetes to improve your understanding of the impact this disease can have on balance function.auditory, textual, visual129USDSubscriptionUnlimited COURSE Access for $129/yearOnlineOnlyAudiologyOnlinewww.audiologyonline.comVestibular Care for Diabetic PatientsVestibular dysfunction and significant fall risks are more prevalent in the diabetic population. Learn about the pathophysiology and epidemiology of diabetes to improve your understanding of the impact this disease can have on balance function.37736OnlinePT60M
'I am a type 1 diabetic myself, so while I know a lot of this information just from years of living with the disease and being educated on it, it is nice to see it portrayed in the context of Audiology'Read Reviews
Vestibular dysfunction and significant fall risks are more prevalent in the diabetic population. Learn about the pathophysiology and epidemiology of diabetes to improve your understanding of the impact this disease can have on balance function.