Ultrasonographic measurement of optic nerve sheath diameter (ONSD) is a simple, non-invasive, yet reliable technique for ICP assessment. Previous studies have demonstrated that ultrasonographic measurement of ONSD correlates with the degree of ICP and can detect intracranial hypertension in a variety of clinical settings.
It was planned to measure the optic nerve sheath throughout the surgery with the help of a linear ultrasound probe.
Ultrasonographically, in each measurement, the optic nerve sheath diameter (ONSD) was detected 3 mm behind the entry point of the optic nerve into the globe in both eyes. ONSD will be measured bilaterally 3 mm behind the papilla. It will be evaluated by transverse measurement for each optic nerve.
