American Board of Psychiatry and Neurology (ABPN) Practice Exam 2025 - Free ABPN Practice Questions and Study Guide

The primary purpose of conducting a lumbar puncture in a patient suspected of having increased intracranial pressure is to measure cerebrospinal fluid (CSF) opening pressure. This measurement is crucial because it provides immediate information about the presence and extent of increased intracranial pressure. Elevated opening pressure can indicate various conditions, including intracranial hemorrhage, brain tumors, or idiopathic intracranial hypertension.

While diagnosing a brain tumor, checking for infections, or performing a CSF analysis for malignancy are also important reasons for conducting a lumbar puncture, they are secondary to the primary purpose of assessing the pressure within the CSF. Identifying elevated CSF pressure allows for appropriate management decisions, including therapeutic interventions such as potential lumbar drain placement or treatment for the underlying cause of increased intracranial pressure, making it a critical initial step in the evaluation of such patients.