FIG 4.

Development of hyperostosis in a 67-year-old man with 2 decades of waxing and waning SIH symptoms with a history of remote CSF leak at C2–C4. A, Axial CT head image at 45 years of age shows qualitatively normal calvarial thickness. B, Sagittal T1-weighted MR image at 48 years of age demonstrates severe brain sag and a suggestion of developing layered hyperostosis. Diffuse pachymeningeal thickening and enhancement are also present (not shown). C, The most recent axial head CT at 67 years of age demonstrates new layered calvarial hyperostosis.