Comparison of measurements from patients with IIH and control subjects^{^a}

	Tonsillar Position (mm)	Obex Position (mm)	Prepontine Cistern Width (mm)
Patients with IIH (n = 43)	2.3 ± 2.8^{^b}	−7.9 ± 2.8^{^b}	5.1 ± 1.8
Control subjects (n= 44)	0.7 ± 1.9	−9.4 ± 2.9	4.9 ± 1.5

↵a Results are reported as mean ± SD. Note that negative numbers are above the foramen magnum and positive numbers are below the foramen magnum.
↵b Results that demonstrated significant difference (P < .05) between patients with IIH and healthy subjects.