Lumbar puncture may also be indicated in selected cases such as patients who are immunocompromised, suspected subacute or chronic meningitis, and a low or high cerebrospinal fluid pressure syndrome. The yield of neuroimaging in patients with new daily headaches and then a few examples of secondary causes PI3K inhibitor will be discussed. Subacute or Chronic Headaches and a Normal Neurologic

Examination.— A number of studies have reported the yield of neuroimaging in headaches present for 1 month or more mostly with a normal neurological exam but none specifically with patients meeting criteria for NDPH. Tsushima and Endo22 retrospectively reviewed the clinical data and magnetic resonance (MR) studies of 306 adult patients (136 men and 170 woman) referred for MRI evaluation of chronic or recurrent headache with a duration of 1 month or more, no other neurologic symptoms or focal findings at physical examination, and no prior head surgery, head trauma, or seizure with the following results: 55.2% had no abnormalities, 44.1% had minor abnormalities, and 0.7% (2) had clinically significant abnormalities (pituitary macroadenoma and subdural hematoma). Neither contrast material enhancement (n = 195) nor repeated

MRI (n = 23) contributed to the diagnosis. Sempere and colleagues23 reported a study of 1876 consecutive patients (1243 women, 633 men) aged 15 years or older, with a mean age of 38 years, with headaches that had an onset at least 4 weeks previously who were referred to 2 neurology clinics in Spain. One-third of PKC inhibitor see more the headaches were new onset, and two-thirds had been present for more than 1 year. Subjects had the following types: migraine (49%), tension (35.4%), cluster (1.1%), posttraumatic (3.7%), and indeterminate

(10.8%). Normal neurological examinations were found in 99.2% of the patients. CT scan was performed in 1432 patients and MRI in 580; 136 patients underwent both studies. Neuroimaging studies detected significant lesions in 22 patients (1.2%), of whom 17 had a normal neurological examination. The only variable or “red flag” associated with a higher probability of intracranial abnormalities was an abnormal neurological examination with a likelihood ratio of 42. The diagnoses in these 17 patients were pituitary adenoma (n = 3), large arachnoid cyst (n = 2), meningioma (n = 2), hydrocephalus (n = 2), Arnold-Chiari Type I malformation, ischemic stroke, cavernous angioma, arteriovenous malformation, low-grade astrocytoma, brain stem glioma, colloid cyst, posterior fossa papilloma (one of each). Of these 17 patients, 8 were treated surgically: hydrocephalus (n = 2), pituitary adenoma, large arachnoid cyst, meningioma, arteriovenous malformation, colloid cyst and papilloma (one of each). The rate of significant intracranial abnormalities in patients with headache and normal neurological examination was 0.9%.