tinnitus (high-pitched ringing in the ear) and a sense of aural fullness, typically evolving slowly over the course of several months or years. Presentation of vestibular impairments is not a main feature; the slow growing nature of this tumor allows for ongoing compensation of the CNS to the gradual loss of vestibular function (Baloh & Halmagyi, 1996), but can be a chief complaint in more than 30% of patients (Olshan et al., 2014). Given the location of the neoplasm and its proximity to the facial nerve at the level of the brainstem (CN VI), patient presentation can also include hemifacial paralysis (Baloh & Halmagyi, 1996; Olshan et al., 2014). A perilymphatic fistula is an abnormality or patency that occurs in the round and oval windows of the middle ear, allowing leakage of perilymph fluid from the semicircular canals to the middle ear. The perilymphatic fistula may be a result of chronic pathological elasticity of the bony labyrinth, leading to episodic changes in fluid pressure and results in fluctuating symptoms of vertigo and imbalance, as well as hearing changes. Often, it is a result of an injury, such as a closed head injury, penetrating injury to the tympanic membrane, barotrauma, or vigorous straining, creating a sudden onset of vertigo, imbalance, and tinnitus. If diagnosed immediately, the patient is placed on bedrest with the head elevated for 5 to 10 days to allow healing to take place. The symptoms will often subside and come on only with forceful maneuvers such as straining or sneezing, or changes in pressure in the inner ear. Persons with chronic or worsening symptoms may go on for surgical management.
patients receiving this therapy, permanently damaging hair cells in the vestibular apparatus. As ototoxicity generally affects vestibular structures bilaterally, the patient will present without symptoms of vertigo or dizziness due to the lack of “mismatch” in bilateral vestibular inputs (Baloh & Halmagyi, 1996; Huth et al., 2011). Acoustic neuroma (vestibular schwannoma) is a benign schwannoma that arises on the vestibular portion of CN VIII at the location of the cerebellopontine angle. The incidence of acoustic neuroma is rare, with an incidence of 1.09 per 100,000 in the United States (Kshettry et al., 2015). The initial presentation is unilateral sensorineural hearing loss, Fluctuating function Ménière’s disease and perilymphatic fistula are the vestibular system disorders in this category, with structural abnormalities in the vestibular apparatus underlying the cause of distorted vestibular function. Ménière’s disease is a function of malabsorption of endolymph (endolymphatic hydrops) in the endolymphatic duct and sac within the semicircular canals, creating an altered flow of endolymph. The clinical feature of Ménière’s disease is an acute spontaneous onset of disabling vertigo, postural imbalance, nausea, and vomiting, persisting for 24 hours. Recovery is also spontaneous, with no residual impairments. However, symptoms of balance limitations can persist for several days or weeks for some patients (Herdman & Clendaniel, 2014). Ménière’s disease is primarily managed through medical, surgical, and pharmacological means, with physical therapy care addressing any residual postural control deficits that may present after persistent attacks.
CLINICAL EXAMINATION OF THE VESTIBULAR SYSTEM
process. The clinician should establish whether the patient is experiencing an acute attack of dizziness, described as onset within the last 3 days, is experiencing chronic dizziness, lasting more than 3 days, or if the patient’s dizziness is episodic. Understanding whether the onset was abrupt or insidious as well as particular provoking factors or preceding illness events is also diagnostic. For episodic dizziness, the provoking factor and duration of symptoms in terms of seconds, minutes, or hours are important to elucidate for the purposes of differentiating the source of symptoms and vestibular system impairment. Clinical examination of vestibular function includes a review of systems, specific testing of the oculomotor and vestibular systems, assessment of postural control, and the use of standardized tools to measure the impact the disorder has on the patient’s life. look for changes in muscle strength and coordination, muscle tone, sensation, vision, hearing, speech, and cognition. Cardiac and vascular disorders may cause dizziness upon exertion, postural hypotension, and dizziness provoked with cervical extension motions due to vertebral circulation insufficiency. For the patient with a history of psychological disorders, the onset of psychogenic-related dizziness and balance dysfunction will have a situational trigger, be associated with palpitations, trembling, and shortness of breath, or be motivated by some aspect of secondary gain. A comprehensive review of the patient’s medications, both prescribed and over the counter, is essential to determine whether possible medication side effects or medication interactions are contributing to the patient’s primary complaints. Of particular importance is to determine whether the patient has been prescribed
The clinician begins a clinical or “bedside” examination of vestibular system function by achieving an accurate description of the patient’s complaints. Often, the term dizzy is used to describe a host of symptoms not related to vestibular system dysfunction, such as difficulty with walking, unsteadiness, headache, and lightheadedness. Symptoms of vertigo strongly indicate a vestibular system contribution to the patient’s complaints, while complaints of “lightheadedness” are suggestive of medication side effects, migraine, cardiac, and anxiety among other nonvestibular disorders as the source of the patient’s symptoms. Nausea and vomiting along with dizziness or vertigo is indicative of either central or peripheral vestibular lesions. The temporal nature, onset, and duration of symptoms of dizziness also guide the clinician’s differential assessment Review of systems A review of systems (ROS) is an important component of a comprehensive clinical examination. The ROS, in conjunction with the patient’s subjective report and medical history, gathers information that is vital to the process of differential assessment. In an ROS, the examiner performs a systematic screening of all body systems to identify the source of the patient’s symptoms. For the patient who presents with symptoms that implicate vestibular system dysfunction, it is of utmost importance to determine whether the cardiac system, vascular system, neurological system, psychological disorders, and polypharmacy are contributing factors to the patient’s chief complaint of dizziness and imbalance. When assessing the presence of neurological system impairment as the possible etiology of symptoms of dizziness and impaired postural control, the examiner should
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