Fig. 1. Optic nerve sheath diameter (ONSD), strain ratio (SR), and shear wave elastography (SWE) of the optic nerve (ON) in a normal control subject.
A-C. ONSD measured on ultrasonography was 4.2 mm. (A), strain elastography shows that the SR of the ON is 0.88 (B), and SWE shows that the SWE of the ON is 12.3 kPa (C).
