The assessment of the diameter of the optic nerve sheath (ONSD) using ultrasound can be a very helpful tool in the assessment of increased intracranial pressure in patients operated for urological procedures.

Advantages of using ultrasound in the assessment of intracranial pressure:

simple, bedside examination, repetitive, generally available, cheap, no exposure to X-rays, no need to transport the patient to the CT laboratory

Differential diagnosis:

Widening of the size of the optic nerve sheath outside of increased intracranial pressure may occur in the following pathologies:

optic neuritis optic nerve injuries meningioma of the optic nerve arachnoid cyst around the optic nerve tumors of the cavernous sinus Blood edema may occur due to impaired blood flow. The research is to determine whether the patient's position for urological procedures is safe for the patients and whether as a result of staying in such a position there is no development of cerebral edema.

Inclusion Criteria:

• Patients undergoing urologic operation
• Adults 18 to 90 years of age
• American Society of Anesthesiologists Physical grade 1-3

Exclusion Criteria:

• Patients who did not agree to participate in the study
• Patients with ophthalmic diseases
• Patients with previous history of ophthalmic surgery
• Patients with neurological disorders
• Patients with history of head surgery due to neurological disorders
• Patients with history of disease with increased intracranial pressure
• Patients with history of disease with increased intraocular pressure

Patients undergoing urologic operation Adults 18 to 90 years of age American Society of Anesthesiologists Physical grade 1-3

We are undecided on this point.