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Recurrent unilateral labyrinthine dysfunction, in association with signs and symptoms of cochlear disease (progressive hearing loss and tinnitus), is usually due to Ménière's disease (Chap. 30). When auditory manifestations are absent, the term vestibular neuronitis denotes recurrent monosymptomatic vertigo. Transient ischemic attacks of the posterior cerebral circulation (vertebrobasilar insufficiency) only infrequently cause recurrent vertigo without concomitant motor, sensory, visual, cranial nerve, or cerebellar signs (Chap. 364). Positional vertigo is precipitated by a recumbent head position, either to the right or to the left. Benign paroxysmal positional (or positioning) vertigo (BPPV) of the posterior semicircular canal is particularly common. Although the condition. | Chapter 022. Dizziness and Vertigo Part 3 Recurrent unilateral labyrinthine dysfunction in association with signs and symptoms of cochlear disease progressive hearing loss and tinnitus is usually due to Meniere s disease Chap. 30 . When auditory manifestations are absent the term vestibular neuronitis denotes recurrent monosymptomatic vertigo. Transient ischemic attacks of the posterior cerebral circulation vertebrobasilar insufficiency only infrequently cause recurrent vertigo without concomitant motor sensory visual cranial nerve or cerebellar signs Chap. 364 . Positional vertigo is precipitated by a recumbent head position either to the right or to the left. Benign paroxysmal positional or positioning vertigo BPPV of the posterior semicircular canal is particularly common. Although the condition may be due to head trauma usually no precipitating factors are identified. It generally abates spontaneously after weeks or months. The vertigo and accompanying nystagmus have a distinct pattern of latency fatigability and habituation that differs from the less common central positional vertigo Table 221 due to lesions in and around the fourth ventricle. Moreover the pattern of nystagmus in posterior canal BPPV is distinctive. When supine with the head turned to the side of the offending ear bad ear down the lower eye displays a large-amplitude torsional nystagmus and the upper eye has a lesser degree of torsion combined with upbeating nystagmus. If the eyes are directed to the upper ear the vertical nystagmus in the upper eye increases in amplitude. Mild dysequilibrium when upright may also be present. Table 22-1 Benign Paroxysmal Positional Vertigo and Central Positional Vertigo Features BPPV Central Latency 3-40 s None immediate vertigo and nystagmus Fatigability0 Yes No Habituationc Yes No Intensity of vertigo Severe Mild Reproducibility Variable Good Time between attaining head position and onset of symptoms. Disappearance of symptoms with maintenance of offending .
