Introduction to Dizziness and the Vestibular System David R Friedland, MD, PhD Professor and Vice-Chairman Chief, Division of Otology and Neuro-otologic Skull Base Surgery Chief, Division of Research Department of Otolaryngology and Communication Sciences Medical College of Wisconsin, Milwaukee, WI
8:30 am 9:00 am Introduction to Dizziness and the Vestibular System David Friedland, MD, PhD, Professor & Vice-Chair of Otolaryngology & Communication Sciences, Medical College of Wisconsin, Milwaukee. 9:00 am 9:30 am Clinical Exam for Dizziness Dennis Moore, MD, Otolaryngologist at Lutheran General Hospital, Park Ridge, IL 9:45 am 10:30 am Vestibular Tests and Diagnosis Marcello Cherchi, MD, PhD, Assistant Professor of Neurology, Northwestern University, Chicago 10:30 am 11:00 am Benign Paroxysmal Positional Vertigo (BPPV) Miriam Redleaf, MD, Chief of Otology/ Neurotology/ Skull Base Surgery Services, University of Illinois, Chicago 1:00 pm 1:30 pm Meniere s Disease Richard Wiet, MD, Ear Institute of Chicago, Professor of Clinical Otolaryngology & Neurosurgery, Northwestern University Medical School, Chicago 1:30 pm 2:00 pm Migraine-Associated Vertigo Robert Battista, MD, Ear Insitute of Chicago, Assistant Professor in Clinical Otolaryngology at Northwestern University, Chicago 2:15 pm 2:45 p Vestibular Physical Therapy Janet Helminski, PhD, PT, Vestibular Therapist, Professor of Physical Therapy, Midwestern University, Downers Grove, IL 2:45 pm 3:15 pm Intra-Tympanic Therapy Alan Micco, MD, Associate Professor of Otolaryngology and Neurological Surgery, Northwestern Medical Faculty Foundation, Chicago 3:15 pm 3:45 pm Future Therapies- gene/stem cells/implants Hinrich Staecker, MD, PhD, Professor of Otolaryngology Head & Neck Surgery, University of Kansas, Kansas City, MO
Goals and Objective Understand the complexity of the vestibular system and that dizziness can come from a number of different sources Recognize features of dizziness that come from ear-related disorders Recognize the association of dizziness with migraine Learn about new treatments and potential therapies
Balance System www.resourcesonbalance.com
Descriptions of Dizziness Vertigo Sensation of inappropriate movement Spinning Disequilibrium / Imbalance Unsteadiness; listing to one side Drunk feeling Lightheadedness / Giddiness Woozy, disorientation, feeling off Faint
Descriptions of Dizziness Acute Chronic Wax and wane Episodic Seconds Minutes Hours Days Spontaneous Provoked Position change Visual stimuli Foods Stress Sound / pressure
The Vestibular System Anatomy
The Vestibular System Inner Ear
The Vestibular System Fluid Filled Compartments Balance Hearing
Semicircular Canals Angular Acceleration
Otolith Organs Linear Acceleration
The Vestibular System Passing Information to the Brain Ross et al, Histology, 1995
www.resourcesonbalance.com
The Vestibular System Functions
Vestibular System Sense of Movement Linear acceleration up/down; front/back; left/right (i.e., elevator, airport conveyor) Angular acceleration: Pitch: head shake yes Yaw: head shake no Roll: head shake na-na-nah-nah-nah-nah Sends this information to the brain, eyes, neck, spine, extremities, etc.
Central Integration Both ears send signals to the brain The brain compares both sides and determines plane, speed and degree of movement The brain tells the eyes how to adjust
Balance = Balance Activity high Put in slide with brain in the middle of a see-saw. The inner ears are on either side baseline low
Sensing Motion: Comparing signals Slide showing turning head to one side with the see saw going up on the activated side and down on the other
Vestibular Ocular Reflex VOR Most important vestibular reflex Maintains eye position during motion Extremely fast responses Disturbances are demonstrated by eye examination Eye movements that are inappropriate cause sensations of dizziness
Loss of VOR on Left Side Zee and Minor, 2002
Vestibular Physiology Laws to Live By
Ewald s First Law Stimulation of a semicircular canal generates eye movements in the plane of that canal
Eye Movements Evoked by Stimulation of Individual Semicircular Canals L. Minor, 2001
Nystagmus Opposite the direction evoked by canal excitation Corrective mechanism Rapidly bring eyes back to where they belong Named for the fast direction of motion Left / right; up / down Rotary: clockwise / counterclockwise
Nystagmus Directions
Nystagmus nystagmus
Dizziness Ear Disease Ear diseases can cause Inappropriate signals from the semicircular canals which causes Inappropriate eye movements which causes A sensation of dizziness
Dizziness Non Ear Disease Other diseases do not cause Inappropriate signals from a semicircular canal so they do not cause Inappropriate eye movements but there can be A sensation of dizziness
Ear vs. Non-Ear Clinical examination Vestibular Testing Ear Diseases BPPV Meniere s Disease Non Ear Disease Migraine
8:30 am 9:00 am Introduction to Dizziness and the Vestibular System David Friedland, MD, PhD, Professor & Vice-Chair of Otolaryngology & Communication Sciences, Medical College of Wisconsin, Milwaukee. 9:00 am 9:30 am Clinical Exam for Dizziness Dennis Moore, MD, Otolaryngologist at Lutheran General Hospital, Park Ridge, IL 9:45 am 10:30 am Vestibular Tests and Diagnosis Marcello Cherchi, MD, PhD, Assistant Professor of Neurology, Northwestern University, Chicago 10:30 am 11:00 am Benign Paroxysmal Positional Vertigo (BPPV) Miriam Redleaf, MD, Chief of Otology/ Neurotology/ Skull Base Surgery Services, University of Illinois, Chicago 1:00 pm 1:30 pm Meniere s Disease Richard Wiet, MD, Ear Institute of Chicago, Professor of Clinical Otolaryngology & Neurosurgery, Northwestern University Medical School, Chicago 1:30 pm 2:00 pm Migraine-Associated Vertigo Robert Battista, MD, Ear Insitute of Chicago, Assistant Professor in Clinical Otolaryngology at Northwestern University, Chicago 2:15 pm 2:45 p Vestibular Physical Therapy Janet Helminski, PhD, PT, Vestibular Therapist, Professor of Physical Therapy, Midwestern University, Downers Grove, IL 2:45 pm 3:15 pm Intra-Tympanic Therapy Alan Micco, MD, Associate Professor of Otolaryngology and Neurological Surgery, Northwestern Medical Faculty Foundation, Chicago 3:15 pm 3:45 pm Future Therapies- gene/stem cells/implants Hinrich Staecker, MD, PhD, Professor of Otolaryngology Head & Neck Surgery, University of Kansas, Kansas City, MO