Assertion: astigmatism | /r/HasProperty | necessary
Facets:
Source sentences:
text: If the astigmatism is irregular or of a high degree, glasses or a soft contact lens may not fully correct the astigmatism and a hard contact lens may be necessary to allow the eye to see normally.
text: Astigmatism is an eye condition that can be corrected with the right astigmatism correction techniques, so there is no need to worry if you have developed this problem.
text: If the astigmatism is irregular or of a high degree, glasses or a soft contact lens may not fully correct the astigmatism and a hard (rigid) contact lens may be necessary to allow the eye to see normally.