Ophthalmodynamometric measurement of central retinal vein pressure as surrogate of intracranial pressure in idiopathic intracranial hypertension

Since a direct non-invasive measurement of the cerebrospinal fluid pressure is not available, it was the purpose of the study to describe the non-invasive determination of the central retinal vein pressure as an estimate of an elevated cerebrospinal fluid pressure.

A 28-year-old female patient with blurred vision, nuchal pain and prominent optic discs underwent modified ophthalmodynamometry to determine the central retinal vein pressure as surrogate of the intracranial pressure. A Goldmann contact lens with a pressure sensor mounted into its holding ring was placed onto the cornea. Pressure was applied to the globe by slightly pressing the contact lens until the central retinal vein started to pulsate/collapse.

Despite an abnormally high central retinal vein pressure (OD: 17 arbitrary units; OS: 33 arbitrary units), the neurological examination including magnetic resonance imaging of the brain was unremarkable on the first day. A lumbar puncture revealed a cerebrospinal fluid pressure of 25 cm H₂O, which was at the upper limit of the normal range. Over the next 2 days, ophthalmodynamometry showed increasing measurements of the central retinal vein pressure for both eyes, parallel to elevated cerebrospinal fluid pressure measurements by lumbar puncture, leading to the diagnosis of idiopathic intracranial hypertension. After treatment, the cerebrospinal fluid pressure returned to normal levels, parallel to a decrease in the central retinal vein pressure as determined by ophthalmodynamometry.

Ophthalmodynamometry of the central retinal vein was helpful in the diagnosis of an elevated intracranial pressure, with direct lumbar pressure measurement running parallel to the ophthalmodynamometric measurements.