Assertion: astigmatism's meridian | /r/HasProperty | phi
Facets:
Source sentences:
text: As Naeser  described, any net astigmatism is fully characterized by two polar values, that is the meridional (AKP) and torsional (AKP + 45) powers, where the former is the power acting along a given meridian [PHI] (i.e., preoperatively steeper meridian) and the latter is the force twisting the astigmatic direction out of that plane, thereby giving rise to a cylinder rotation.