Global Journal of Otolaryngology ISSN 2474-7556 Powerpoint presentation Glob J Otolaryngol - Special Issue March 2017 Copyright © All rights are reserved by Lalsa Shilpa Perepa DOI: 10.19080/GJO.2017.05.555664 Subjective Tests for Vestibular Dysfunction Basic Advantages a) Well established - criteria for diagnostic testing Indications pontomedullary b) Insights into site of lesion lesions produce ipsiversive tilts (deviation of a) Brandt and Dietrich [2] found that c) Alerts the examiner Pontomesencephalic lesions produce contraversive tilts subjective visual vertical toward the side of the lesion), Basicd) Disadvantages High specificity (away from the lesion). The deviations accompanied by the a) Require New and improvised versions of test ocularb) Disruption tilt reaction. of both the otolithic and vertical b) Not well supported for diagnosing semicircular canal pathways are thought to be involved inc) theThalamic deviations. lesions c) Low sensitivity may produce either ipsiversive or of the parietoinsular vestibular cortex tend to produce Subjectived) Requires Visual objective Vertical tests test to support findings contraversive tilts of subjective visual vertical. Lesions level of the thalamus and above contraversive deviations. Lesions at the Given By-Bohmer A, Rickenmann J [1]. will not produce an accompanying SVV is an estimation technique whereby a subject adjusts a oculard) Lesions tilt reaction. in the inner ear also produce deviation of visible luminescent line, while seated in complete darkness, to subjective visual vertical due to differences in the tonic whatPrinciple they consider to be upright or true vertical. outpute) Abnormal from the inotolithic headache organs in the inner ear [3]. with migraine SVV or SVH a s me a su r ed i n t he upr ig ht posit ion i s i n f luenced sufferers, particularly those byPurpose the utricles, saccules and horizontal semicircular canals. Limitations . a) To assess utricular function a) Bilateral utricular defects are not assessed Findings questionable to be supported with other tests Sensitivity and specificity b) central connections, including superior vestibular nerve.c) To assess the degree of ocular torsion b) Inability to properly estimate the true vertical when Procedure the light bar was initially inclined in the opposite direction compensation c) SVV is subject to variation over time, due to central a) Subject is made to sit in a dark room. Fukuda Stepping Test position that the individual judges to be vertical b) Individual is asked to align a luminous bar with a Given By Fukuda [4] c) 10 trials are given before the mean and standard would turn to the side of lesion Persons with unilateral peripheral vestibular dysfunction Resultsdeviations of the offset from true vertical are determined. Normal: 2 degrees tilt is considered to be able to set History- middle ear pathology can influence results of A. caloric stimulation due to alteration of thermal conductivity the SVV correctly when the light bar has an initial inclination acrossPrinciple middle ear space. relativelyAbnormal: parallel to theMore body than axis. 2 degrees tilt indicates the peripheral problem that is ipsilateral and offset is towards the B. a) Body rotation results from the unbalanced static activity of the two end organs same side. Glob J Otolaryngol 5(3): GJO.MS.ID.555664 (2017) 001 Global Journal of Otolaryngology rotation plane towards the contra-lesioned b) Imbalance in the yaw ear is interpreted centrally as system. b) Given By Barany in 1910( Related articles in German) c) Deviation of body occurs towards the ipsi-lesioned c) The past-pointing test was one of the first attempts to Purposeside. clinicallyd) The assesspast pointing vestibular falling functions. and slow component of a) Used to assess peripheral VS impairment manifested tone nystagmus are in the same direction. as asymmetry in lower extremity vestibulospinal reflex past pointing and slow component on ipsilateral side I. Acute VS failure-nystagmus on the opposite side but e) Past pointing occurs on same side of target and will b) Labyrinthine dysfunction occur with either limb Procedurec) Indicates possible acoustic neuroma. PrincipleI. Both limbs- vestibulopathy a) With the arms extended at a 90˚ angle in front of the body and the eyes closed, the patient marches in place for a) Asymmetric tonic signals from afferent system 50 steps. organ manifested as a relative abundance of activity from intact end b) Stepping rate -110 steps per minute. c) The angle, direction, and distance of deviation from b) Compensatory VSR elicited in order to maintain the origin should be recorded. position. Hence body rotates towards the lesioned organ, Purpose d) It is helpful to make use of a reference mark system resulting in past pointing. such as a band of tape on the floor oriented along the a) Used to assess tonic imbalance in the output of the sagittal plane at the start of the test or a thin, dense rubber Resultsmat with a polar pattern marked on it peripheralb) Test for vestibular defective system functioning of the vestibular nerve c) Indicative of cerebellar signs A. Normal: 50 steps without significant angular deviation from the starting position (i.e., normal rotation ≤ 30˚). Procedured) Used for assessing vestibulospinal pathways. B. Abnormal: A rotation of greater than 45 degrees in The patient is instructed to extend the arms and place the eitherAdvantages direction is considered to be abnormal. [4,5]. a) Useful test for peripheral VS lesion index finger of one hand on the index finger of the examiner or a static target. Eyes are then closed and arms raised above headResult ands quickly returned to the perceived starting position b) Reveals deficits of VSR compensation when VOR A. Normal: c) A useful screening tool compensation is complete. little lateral deviation finger returns to the starting point with Limitations Abnormal: B. The patient’s hand will drift away from a) FST with and without head shake component is not a the targetPeripheral as the trunkVS lesion: rotates. deviation to one side and reliable screening tool for peripheral vestibular asymmetry in chronic dizzy patients i. compensated peripheral weakness in case of less consistent b) Reliability of predicting imbalance of the labyrinthine Advantagescase. system based on the poor reliability scores- questionable lesion a) Detects acute lesions c) Not reliable for lateralization and localization of b) Gives insight about compensated and decompensated lesions Pastd) pointing Limited and use infalling spontaneous test nystagmus cases Limitations a) Past-pointing is considered to be a sign of tonic imbalance in the output of the peripheral vestibular a) Not reliable in case of chronic vestibulopathy after 002 How to cite this article: Lalsa Shilpa P, Subjective Tests for Vestibular Dysfunction. Glob J Oto 2017; 5(3): 555664. DOI: 10.19080/GJO.2017.03.555664 Global Journal of Otolaryngology compensation has occurred b) Repeated testing produces variable results No vision, proprioception and vestibular function. b) Vestibular problem -eyes open balance maintained lateralization information maintain balance c) Eyes closed-only proprioception insufficient to c) d) LowCannot sensitivity detect compensated vestibular lesions functioning Vertical writing d) Only propioreception- eyes closed - improper VS Purpose a) Variant of past- pointing a) Identifies imbalance in the vestibulospinal reflex due b) Described by Fukuda-1959 [4] to tonic imbalance in peripheral vestibular system afferent vestibular input to the brainstem c) Deviation tendency is due to relative difference in b) To assess the integrity of the dorsal columns of the Procedure spinalProcedure cord. Patients instructed to write a series of characters or The patient is asked to stand with feet together and arms symbols in vertical direction on a piece of paper. With eyes byResults side with eyes first opened and then closed. openResults and then with eyes closed. imbalance compensated a) Open eyes - relative reduction of vestibular input line of characters to cerebellum a) Eyes open- Normals and Vestibular patients-vertical b) Closed eyes- cerebellar ataxia. and deviation to the side of lesion b) Eyes closed- Unilateral Peripheral lesions-slanting c) With eyes open poorproblem balance - in vestibular or c) Central overcompensation of unilateral peripheral proprioceptive systems. vestibular impairment-opposite side of lesion d) Eyes closed- e) Peripheral lesion- Limitation f) Central lesion- patient sways to side of lesion g) Bilateral or Unilateral Instability Peripheral VS lesion- a) b) CannotSome mild only concludeotologic asdisorders-otitis Vestibular site media-similarof lesion IndicationsNegative (Table 1). Rombergfinding Test a) Vitamin B12 deficiency - Subacute combined a) First described by Moritz Heinrich von Romberg who degeneration of the cord, found that patients with tabes dorsalis (neurosyphilis) often complainedb) The of test increased should unsteadiness be performed in thein dark.all patients who b) Diabetic peripheral large fibre neuropathy, c) d) Tabes Friedrich’s dorsalis ataxia, ataxia complain of dizziness, imbalance or falls to rule out sensory Table 1: Sensary Inputs. c) Romberg’s test is a test of the proprioception Test Condition Description Sensory inputs receptorsRomberg and sign pathways function. vestibularVisual, The Romberg sign demonstrates loss of postural control Eyes open firm surface proprioceptive, in the absence of visual input suggestive of proprioceptive vestibular Proprioceptive,
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