Biomaterial Database

Visual fixation of caloric nystagmus with special reference to a new index. 1984

I Kato, and J Watanabe, and T Nakamura, and Y Koike

The effects of visual fixation upon caloric nystagmus were computed in each parameter as a measure. The percentage reduction established with slow-phase velocity best distinguished normal from abnormal visual fixation at the line of 60%. However, if a +/- 5% safety margin is taken into account, 11 of 176 ears showed false-negatives. The number of nystagmus beats in normals decreased markedly during the period of fixation. In abnormals, the number of nystagmus beats increased definitely during the fixation period. Based on this fact, the product of slow-phase velocity multiplied by the number of nystagmus beats was assessed as the fixation-suppression index. As a result, 11 ears showing false-negative slow-phase velocity decreased to 2 ears. Thus, this modified fixation-suppression index seems to be an appropriate parameter to separate normal from abnormal fixation-suppression of caloric nystagmus.

UI	MeSH Term	Description	Entries
D008838	Microcomputers	Small computers using LSI (large-scale integration) microprocessor chips as the CPU (central processing unit) and semiconductor memories for compact, inexpensive storage of program instructions and data. They are smaller and less expensive than minicomputers and are usually built into a dedicated system where they are optimized for a particular application. "Microprocessor" may refer to just the CPU or the entire microcomputer.	Computers, Personal,Microprocessors,Computer, Personal,Microcomputer,Microprocessor,Personal Computer,Personal Computers
D009759	Nystagmus, Pathologic	Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)	Convergence Nystagmus,Horizontal Nystagmus,Jerk Nystagmus,Pendular Nystagmus,Periodic Alternating Nystagmus,Rotary Nystagmus,See-Saw Nystagmus,Vertical Nystagmus,Conjugate Nystagmus,Dissociated Nystagmus,Fatigable Positional Nystagmus,Multidirectional Nystagmus,Non-Fatigable Positional Nystagmus,Permanent Nystagmus,Rebound Nystagmus,Retraction Nystagmus,Rotational Nystagmus,Spontaneous Ocular Nystagmus,Symptomatic Nystagmus,Temporary Nystagmus,Unidirectional Nystagmus,Non Fatigable Positional Nystagmus,Nystagmus, Conjugate,Nystagmus, Convergence,Nystagmus, Dissociated,Nystagmus, Fatigable Positional,Nystagmus, Horizontal,Nystagmus, Jerk,Nystagmus, Multidirectional,Nystagmus, Non-Fatigable Positional,Nystagmus, Pendular,Nystagmus, Periodic Alternating,Nystagmus, Permanent,Nystagmus, Rebound,Nystagmus, Retraction,Nystagmus, Rotary,Nystagmus, Rotational,Nystagmus, See-Saw,Nystagmus, Spontaneous Ocular,Nystagmus, Symptomatic,Nystagmus, Temporary,Nystagmus, Unidirectional,Nystagmus, Vertical,Ocular Nystagmus, Spontaneous,Pathologic Nystagmus,Positional Nystagmus, Non-Fatigable,See Saw Nystagmus
D002150	Caloric Tests	Elicitation of a rotatory nystagmus by stimulating the semicircular canals with water or air which is above or below body temperature. In warm caloric stimulation a rotatory nystagmus is developed toward the side of the stimulated ear; in cold, away from the stimulated side. Absence of nystagmus indicates the labyrinth is not functioning.	Barany Test,Barany's Test,Baranys Test,Caloric Test,Test, Barany,Test, Barany's,Test, Caloric,Tests, Caloric
D005188	False Negative Reactions	Negative test results in subjects who possess the attribute for which the test is conducted. The labeling of diseased persons as healthy when screening in the detection of disease. (Last, A Dictionary of Epidemiology, 2d ed)	False Negative Reaction,Reaction, False Negative,Reactions, False Negative
D005403	Fixation, Ocular	Positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.	Focusing, Ocular,Ocular Fixation,Eye Gaze,Eye Gazes,Gaze, Eye,Gazes, Eye,Ocular Focusing
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults