Vestibular Glossary

Jeff Walter PT, DPT, NCS complier edited and linked by Timothy C. Hain, MD Page last modified: January 7, 2012

Acephalgic: Without head pain, usually in the context of migraine.

Acrophobia: Fear of heights

Ageotropic nystagmus: Movement tendency directed away from the earth, usually found in lateral canal BPPV

Agoraphobia: Fear of busy, open marketplaces

Alexander’s Law: Peripheral vestibular-origin nystagmus is enhanced with gaze directed toward the fast phase. See gaze-evoked nystagmus.

Aminoglycosides: Group of antibiotics that can produce vestibular or cochlear toxicity

Ampulla: Dilated ending of the semicircular canal containing the cupula

Ampullofugal: Refers to displacement “away” from the ampulla

Ampullopetal: Refers to displacement “toward” the ampulla

Antihistamine: Class of medications utilized to address chronic vertigo or motion sickness. An example is meclizine.

Antivert (Meclizine): Antihistamine used to promote vestibular sedation with chronic vertigo or motion sickness

Ataxia: incoordination

Ativan (Lorazepam): Benzodiazepine used to promote vestibular sedation with acute vertigo

Audiometry: Test of hearing

Autophony: Hearing of a person's own voice, breathing or other self-generated sounds. Usually seen in eustachian tube disorders (ETD).

Barany Maneuver (aka Dix-Hallpike, Hallpike): Testing procedure intended to identify anterior or posterior canal BPPV

Benzodiazepines: Class of medications utilized to promote vestibular sedation with acute vertigo

Caloric Testing: Component of ENG/VNG testing, intended to assess for asymmetric horizontal canal / superior vestibular nerve function, that involves irrigation of warm and cold water or air into the external auditory canal

Canalithiasis: Variant of BPPV where otoconia are free floating within the semicircular canal

Canalith Repositioning Maneuvers: Treatments intended to move displaced otoconia from the affected semicircular canal to the utricle

Cephalgia: Head pain

Cerebellum: Portion of the brain that modulates balance, limb and eye movements

Cholesteatoma: Mass growing within a confined space, often the middle ear

Cisplatin: Chemotherapy agent toxic to hearing

Cochlea: the auditory portion of the labyrinth

Collic: Referring to the neck

Cupulolithiasis: Variant of BPPV where otoconia are adherent to the cupula

Dehiscence: Refers to a split or opening in a structure, such as in superior canal dehiscence

Diazepam (Valium): Benzodiazepine used to promote vestibular sedation

Dimenhydrinate (Dramamine): Antihistamine used to promote vestibular sedation with chronic vertigo or motion sickness

Diplopia: Double vision

Dix-Hallpike Maneuver (aka Barany, Hallpike): Testing procedure intended to identify anterior or posterior canal BPPV

Dizziness: Non-specific term encompassing feelings of imbalance, spinning and lightheadedness

Dramamine (Dimenhydrinate): Antihistamine used to promote vestibular sedation with chronic vertigo or motion sickness

Dysarthria: Difficulty articulating words

Disequilibrium (or Dysequilibrium): Subjective sense of unsteadiness

Electronystagmography: Measurement of eye movements with electrodes surrounding the orbit

Emesis: vomiting

Epley Maneuver: Treatment for posterior canal BPPV

Ewald’s Laws

1st:: The axis of nystagmus parallels the anatomic axis of the semicircular canal that generated it.
2nd: Ampullopetal endolymphatic flow produces a stronger response than ampullofugal flow in the horizontal canal

Fistula (Perilymph): Abnormal opening between the fluid-filled inner ear and the air-filled middle ear

Fixation: Maintenance of gaze on a single location

Fovea: Center portion of the retina, the region of highest visual acuity

Frenzel goggles: Utilized to block gaze fixation with the use of magnified lenses and illumination

Fukuda Step Test: Postural control test utilized to uncompensated unilateral vestibular loss

Fullness: Perception of ear pressure

Gentamicin: Antibiotic with vestibular-toxic properties

Geotropic: Movement tendency directed toward the earth

Habituation: An acquired tolerance gained by repeated exposure to a particular stimulus

Hallpike Maneuver (Barany, Dix-Hallpike): Testing procedure intended to identify anterior or posterior canal BPPV

Hydrops: Distention of the labyrinth with fluid, a likely component of Meniere’s Disease

Hyperacusis: Discomfort induced by noises that are not painful to most people.

Imbalance: Observable unsteadiness

Labyrinth: Refers to the inner ear which includes the cochlea and vestibular organs

Latency: The time between the initiation of a stimulus and the clinical manifestation of the disease

Lateropulsion: Tendency to fall to the side

Lightheadedness: Feeling of faintness

Lorazepam (Ativan): Benzodiazepine used to promote vestibular sedation with acute vertigo

Otolithic Crisis of Tumarkin: A sudden unexplained fall without loss of consciousness or vertigo, attributed to an abrupt change in otolithic input. Usually found in Meniere's disease.

Maculae: Sensory epithelium contains hair cells that are stimulated by linear acceleration and deceleration within the otolithic organs

Mastoid: Sinus at the base of the skull behind the ear, containing air spaces that connect with the middle ear cavity

Meclizine (Antivert): Antihistamine used to promote vestibular sedation

Nystagmus: Involuntary jumping of eyes that resets the eyes during prolonged rotation and directs gaze towards the oncoming visual scene

Ocular flutter: Bursts of saccadic activity that involve rapid, involuntary, uni-planar, conjugate eye movements around the point of fixation without an inter-saccadic interval

Ophthalmoplegia: Weakness of one or more of the eye muscles that control eye movment

Optokinetic: generates eye movements in response to sustained rotations of objects that encompass a large portion of the visual field

Opsoclonus: Bursts of saccadic activity that involves rapid, involuntary, non-rhythmic, multidirectional, conjugate eye movements without significant inter-saccadic interval.

Orthogonal: Intersecting at 90 degree angles

Orthostatic Tremor: Rhythmical muscle contractions present with standing

Oscillopsia: Gaze instability, usually due to bilateral vestibular reduction

Ossicles: Middle ear bones (malleus, incus and stapes) that transmit sound from the tympanic membrane to the oval window of the inner ears.

Otalgia: Pain in the ear

Otoconia: Calcium carbonate crystals embedded within the maculae within the otolith organs.

Otolithic Crisis of Tumarkin: Sudden, conscious falls that occur without warning likely due to inappropriate otolith activity, usually associated with Meniere's disease.

Otolith Organs: Refers to the utricle and saccule

Otoliths: Otoconia

Ototoxic: Having a harmful affect on labyrinthine structures

Paraneoplastic: Caused by the presence of cancer in the body but not the physical presence of cancerous tissue in the part or organ affected

Paroxysmal: Recurrent and sudden intensification of symptoms

Perilymph: Fluid situated between the bony and membranous labyrinth

Phenergan (Promethazine): Antihistamine utilized to address chronic vertigo and motion sickness

Phonophobia: Fear/sensitivity to sound. Associated with migraine and hyperacusis

Photophobia: Fear/sensitivity to light, usually associated with migraine.

Pitch: To turn about a medial-lateral (y) axis. In other words, the axis between your ears. See here for more.

Promethazine (Phenergan): Antihistamine utilized to address chronic vertigo and motion sickness

Pulsion: The feeling of being pulled in a certain direction

Roll: To turn about an anterior-posterior (x) axis. See here for more.

Roll Test: Maneuver intended to identify horizontal canal BPPV

Saccades: Abrupt, rapid movement of both eyes utilized to change the point of fixation

Saccule: Otolithic organ that primarily detects vertical and forward linear accelerations

Schwannoma: Solid, usually benign tumor derived from Schwann cells. When involving the 8th nerve, termed an acoustic neuroma.

Semicircular canal: Circular, fluid-filled, ducts within the vestibular organ responsible; structure promotes the detection of angular accelerations

Semont Maneuver: Treatment for posterior canal BPPV, canalithiasis or cupulolithiasis

Smooth pursuit: Maintains image of a small moving target on the fovea

Stapedectomy: Surgical removal of the stapes followed by prosthetic replacement. Usually for otosclerosis.

Syncope: Loss of consciousness

Temporal Bone: Portion of the skull containing the labyrinth. Hardest bone in the body.

Tinnitus: Ringing in the ears

Torsion: Rotation around the anterior-posterior. Also known as roll.

Tropia: Deviation in ocular alignment that persists with both eyes viewing.

Tullio’s Phenomena: Vestibular symptoms elicited by sound. Usually associated with superior canal dehiscence.

Utricle: Otolithic organ that primarily detects horizontal linear accelerations

Utriculofugal: displacement away from the utricle

Utriculopetal: displacement toward the utricle

Valium (Diazepam): Benzodiazepine used for vestibular sedation.

Valsalva Maneuver: Attempt to forcibly exhale with the glottis, nose and mouth closed. Used to diagnose superior canal dehiscence as well as some types of syncope.

Vestibular-Evoked Myogenic Potential (VEMP): Laboratory test of saccular / inferior vestibular nerve function

Vergence: Movement of the eyes in opposite directions, usually induced by taking up near or far vision

Vertigo: Dizziness characterized by a sense of spinning

Vestibular: Refers to the vestibular (balance) portion of the labyrinthine organ

Vestibulopathy: Disease to the vestibular organ

Visual fixation: Holds the image of a stationary object on the fovea by minimizing ocular drifts

Videonystagmography: Measurement of eye movements with the use of video

Yaw: To turn about a vertical (z) axis

Abbreviations

ABC: Activities specific Balance Confidence scale. Used to quantify balance by physical therapist.

BOS: Base Of Support

BPPV: Benign Paroxysmal Positional Vertigo