Biomaterial Database

Periodic downbeat nystagmus. 1998

R Du Pasquier, and F Vingerhoets, and A B Safran, and T Landis

Neurology Clinic, Geneva's University Hospital, Genève, Switzerland.

The authors observed a periodic downbeat nystagmus with a cycle of 3 minutes 30 seconds, beating downward for a period of 90 seconds every 2 minutes. It lasted 86 hours in a patient with severe hypomagnesemia associated with complications from scleroderma. There was no lesion on brain imaging, and an EEG performed during the nystagmus was normal, indicating that the most likely explanation for this periodic nystagmus is metabolic. This form of nystagmus may have resulted from severe hypomagnesemia, possibly associated with thiamine deficiency.

UI	MeSH Term	Description	Entries
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D008275	Magnesium Deficiency	A nutritional condition produced by a deficiency of magnesium in the diet, characterized by anorexia, nausea, vomiting, lethargy, and weakness. Symptoms are paresthesias, muscle cramps, irritability, decreased attention span, and mental confusion, possibly requiring months to appear. Deficiency of body magnesium can exist even when serum values are normal. In addition, magnesium deficiency may be organ-selective, since certain tissues become deficient before others. (Harrison's Principles of Internal Medicine, 12th ed, p1936)	Deficiency, Magnesium,Deficiencies, Magnesium,Magnesium Deficiencies
D008279	Magnetic Resonance Imaging	Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.	Chemical Shift Imaging,MR Tomography,MRI Scans,MRI, Functional,Magnetic Resonance Image,Magnetic Resonance Imaging, Functional,Magnetization Transfer Contrast Imaging,NMR Imaging,NMR Tomography,Tomography, NMR,Tomography, Proton Spin,fMRI,Functional Magnetic Resonance Imaging,Imaging, Chemical Shift,Proton Spin Tomography,Spin Echo Imaging,Steady-State Free Precession MRI,Tomography, MR,Zeugmatography,Chemical Shift Imagings,Echo Imaging, Spin,Echo Imagings, Spin,Functional MRI,Functional MRIs,Image, Magnetic Resonance,Imaging, Magnetic Resonance,Imaging, NMR,Imaging, Spin Echo,Imagings, Chemical Shift,Imagings, Spin Echo,MRI Scan,MRIs, Functional,Magnetic Resonance Images,Resonance Image, Magnetic,Scan, MRI,Scans, MRI,Shift Imaging, Chemical,Shift Imagings, Chemical,Spin Echo Imagings,Steady State Free Precession MRI
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
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002136	Calcium, Dietary	Calcium compounds in DIETARY SUPPLEMENTS or in food that supply the body with calcium.	Dietary Calcium
D004569	Electroencephalography	Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.	EEG,Electroencephalogram,Electroencephalograms
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000204	Activity Cycles	Bouts of physical irritability or movement alternating with periods of quiescence. It includes biochemical activity and hormonal activity which may be cellular. These cycles are shorter than 24 hours and include sleep-wakefulness cycles and the periodic activation of the digestive system.	Activity Cycle,Cycle, Activity,Cycles, Activity