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Rundle's Curve: A Useful Construct That Does Not Fit All
Antonio A V Cruz1, Juliana A Guimarães, Denny M Garcia
1Department of Ophthalmology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil.
Purpose:
The purpose of this study was to analyze Rundle's original data and subsequent articles on Graves orbitopathy (GO) natural history.
Methods:
Rundle's texts were analyzed qualitatively and quantitatively. Serial measurements were plotted and fitted with different functions. Subsequent articles in the English literature on the natural history of GO were also analyzed.
Results:
Different functions such as simple linear regressions, parabolic, saturating exponential growth, and exponential decay functions were well fitted for Rundle's data on measurements of proptosis and supraduction along time. The few quantitative data of the same variables post-Rundle were also well-fitted with various functions.
Conclusion:
Rundle described in his articles, from 1945 to 1957, 2 phases of ocular changes in GO: dynamic and static. However, he did not mention the pathophysiology of these phases nor used the terms inflammatory and cicatricial. Actually, most of his observations and the subsequent data in the literature on proptosis and supraduction did not obey the biphasic pattern of the so-called Rundle's curve.
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