neurologic disorders
Post–Lumbar Puncture and Other Low–Pressure Headaches
Diagnosis of Post LP and Other Low Pressure Headaches
Clinical evaluation Post-LP headache is clinically obvious, and testing is rarely needed; other low-pressure headaches, regardless of cause, may require brain imaging. MRI with gadolinium often shows evidence of low CSF pressure, with diffuse enhancement of the pachymeninges and, in severe cases, downward sagging of the brain. CSF pressure is typically low or unobtainable if patients have been upright for any length of time. Spontaneous CSF leaks are more difficult to diagnose and should be considered in patients with orthostatic headache relieved by recumbency. 