Dexmedetomidine Versus Propofol for Sedation in Stereotactic Brain Biopsy

Inclusion criteria: Patients with: * brain secondaries from the lung/breast/pancreas * tuberculoma * pyogenic abscess * intra-axial supratentorial space occupying lesion with or without hydrocephalus \*an average duration of the procedure 1- 2hr 30 min * an available caregiver for overnight observation * patient relative proximity to the hospital Exclusion criteria Patients with: * morbid obesity (body mass index \>35 kg/m2) * significant comorbidities (a known history of hepatic disease, renal dysfunction, hypertension, and chronic pain) * history of drug or alcohol abuse * an allergic reaction to one of the study medications * anticipated difficult airway * uncontrolled epilepsy * poor neurological status * neuropsychological unsuitability taking psychotropic drugs (benzodiazepines and barbiturates) * patients with brain stem lesions (vital areas of brain) * un-cooperative * refusing adults * patients with ventricular drain * already inpatient * Intubated patients and those who had a prior craniotomy .