TY - JOUR
T1 - Reversible alteration of the visual evoked potential in hypothyroidism
AU - Ladenson, Paul W.
AU - Stakes, John W.
AU - Ridgway, E. Chester
N1 - Funding Information:
From the Thyroid Unit, Medical Service, and the Clinical Neurophysiology Laboratory, Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts. This work was supported in part by Grants RR-1066, AM-16791, and HL-07354 from the National Institutes of Health, Bethesda, Maryland. An abstract based upon a portion of this study was presented at the 56th Annual Meeting of the American Thyroid Association, Quebec, Canada, 1982. Dr. Ladenson is a Teaching and Research Scholar of the American College of Physicians, Philadelphia, Pennsylvania. Manuscript accepted June 14, 1984. l Current address and address for reprint requests: Division of Endocrinology and Metabolism, Sinai Hospital, Baltimore, Maryland 21215.
PY - 1984/12
Y1 - 1984/12
N2 - The pattern-shift evoked potential was measured in 19 hypothyroid patients before treatment, and after short- (one week) and long-term (12 to 24 weeks) thyroid hormone replacement therapy. Before treatment, nine patients had an abnormally prolonged visual evoked potential latency, more than 115 msec. After one week of therapy with 50 μg per day of l-triiodothyronine, the mean visual evoked potential latency for the entire group was unchanged, 114 ± 8to114 ± 7 msec. However, long-term therapy with 100 to 200 μg per day of l-thyroxine significantly shortened the visual evoked potential latency to 105 ± 1 msec (p < 0.001). In eight of the nine patients with initially abnormal results, the visual evoked potential latency was completely restored to normal. The visual evoked potential amplitude was also significantly changed by long-term l-thyroxine, 4.8 ± 0.7 to 9.0 ± 1.0 μV (p < 0.01). It is concluded that the visual evoked potential is reversibly altered in hypothyroidism. This neurophysiologic parameter permits quantitation of the effects of hypothyroidism on the central nervous system and the extent and rate of response to thyroid hormone replacement therapy.
AB - The pattern-shift evoked potential was measured in 19 hypothyroid patients before treatment, and after short- (one week) and long-term (12 to 24 weeks) thyroid hormone replacement therapy. Before treatment, nine patients had an abnormally prolonged visual evoked potential latency, more than 115 msec. After one week of therapy with 50 μg per day of l-triiodothyronine, the mean visual evoked potential latency for the entire group was unchanged, 114 ± 8to114 ± 7 msec. However, long-term therapy with 100 to 200 μg per day of l-thyroxine significantly shortened the visual evoked potential latency to 105 ± 1 msec (p < 0.001). In eight of the nine patients with initially abnormal results, the visual evoked potential latency was completely restored to normal. The visual evoked potential amplitude was also significantly changed by long-term l-thyroxine, 4.8 ± 0.7 to 9.0 ± 1.0 μV (p < 0.01). It is concluded that the visual evoked potential is reversibly altered in hypothyroidism. This neurophysiologic parameter permits quantitation of the effects of hypothyroidism on the central nervous system and the extent and rate of response to thyroid hormone replacement therapy.
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U2 - 10.1016/0002-9343(84)90180-3
DO - 10.1016/0002-9343(84)90180-3
M3 - Article
C2 - 6507455
AN - SCOPUS:0021684549
SN - 0002-9343
VL - 77
SP - 1010
EP - 1014
JO - The American journal of medicine
JF - The American journal of medicine
IS - 6
ER -