T1-weighted MRI confirms postdural puncture headache.(Obstetrics)

ASHEVILLE, N.C. -- If you suspect a postdural puncture headache but aren't sure, order a T1-weighted MRI with gadolinium contrast for the patient, David C. Mayer, M.D., advised at the Southern Obstetric and Gynecologic Seminar.

"It used to be that there were no imaging studies available to make the diagnosis of postdural puncture headache. That has now changed," said Dr. Mayer, a professor of obstetrics and gynecology and of anesthesiology at the University of North Carolina at Chapel Hill.

Signs of postdural puncture headaches (PDPH) cannot be seen on CT scans (with and without contrast) or noncontrast MRI.

MRI (T1 weighted) with gadolinium contrast, however, reveals changes that can make a difference in the diagnosis of PDPH. This particular type of MRI rules out more serious conditions, such as subdural hematoma and intracranial masses. The two key findings using T1-weighted contrast MRI are meningeal enhancement and descent or sagging of the brain. Diffuse meningeal enhancement is seen on the MRI. "The meninges ... light up with gadolinium," Dr. Mayer explained.

Less frequently, the pituitary may appear large--though this can be seen with CT as well--and engorged cerebral venous sinuses may also be seen.

Downward displacement of the brain can also be seen (similar to a Chiari ...