Optic Nerve Sheath Diameter: A Non-Invasive Indicator of Intracranial Pressure in the Intensive Care Unit Monitoring

Evaluation of the Effect of Cerebrospinal Fluid Drainage on Optic Nerve Sheath Diameter in Patients Installed External Ventricular Drainage Catheter Due to Intracranial Pathology in the Intensive Care Unit

Determination of high intracranial pressure (ICP) is necessary for the treatment of patients with raised ICP to improve long-term neurological outcomes. Ultrasonographic optic nerve sheath diameter (ONSD) measurement is a noninvasive, easily performed and cost effective technique for detecting high ICP.

ICP measurements via ventricular catheters provide CSF drainage and ICP reduction. The normal ICP value is less than 15 mmHg in adults. In the literature the correlation of ONSD and invasive ICP measurements were determined. The aim of study is to evaluate the correlation of ONSD and direct ICP measurements and to determine cut off ONSD value to detect ICP ≥15 mmHg.

Inclusion Criteria:

• 18-80 aged patients
• With an external ventricular drainage catheter due to intracranial pathology

Exclusion Criteria:

• Under the age of 18
• Orbital tumors
• Graves' disease
• Exophthalmos
• Sarcoidosis
• Optic neuropathy
• Meningitis
• Ocular trauma
• Lung diseases