Related Experiment Video
Updated: Mar 6, 2026

Translaminar Autonomous System Model for the Modulation of Intraocular and Intracranial Pressure in Human Donor Posterior Segments
Published on: April 24, 2020
The Optic Canal: A Bottleneck for Cerebrospinal Fluid Dynamics in Normal-Tension Glaucoma?
Achmed Pircher1, Margherita Montali2, Jatta Berberat3
1Department of Ophthalmology, Cantonal Hospital , Aarau, Aargau , Switzerland.
Purpose:
To report on the optic canal cross-sectional area (OCA) in Caucasian patients with normal-tension glaucoma (NTG) compared with Caucasian control subjects without known optic nerve (ON) diseases.
Methods:
Retrospective analysis of computed tomographic images of the cranium and orbits in 56 NTG patients (30 females and 26 males; 99 of 112 eyes; mean age 67.7 ± 11.1 years). Fifty-six age- and gender-matched subjects (mean age: 68.0 ± 11.2 years) without known ON diseases served as controls. The OCA at the orbital opening was measured in square millimeters by using the tool "freehand." Statistical analysis was performed by using the independent two-tailed t-test.
Results:
The mean orbital opening OCA in NTGs measured 14.5 ± 3.5 mm2 (right OCA: 14.4 ± 3.6 mm2, left OCA: 14.5 ± 3.4 mm2) and in controls measured 18.3 ± 2.6 mm2 (right OCA: 18.5 ± 2.7 mm2, left OCA: 18.1 ± 2.5 mm2). The difference between NTG and controls was statistically significant (p < 0.000 for the right OCA, p < 0.000 for the left OCA).
Conclusion:
This study demonstrates narrower OCAs in Caucasian NTG patients compared with Caucasian control subjects without known ON diseases. Narrower OCAs might contribute to a discontinuity of the cerebrospinal fluid flow between the intracranial and orbital subarachnoid space in NTG patients. This might have an influence onto the pathophysiology in NTG.
Related Concept Videos
Glaucoma: Overview
Open Angle Glaucoma: Treatment
Drugs such as carbonic anhydrase inhibitors, α2- and...
Angle Closure Glaucoma: Treatment
Cerebrospinal Fluid
CSF Production
CSF is produced mainly in the choroid plexus, a network of capillaries and ependymal cells located within the ventricular system of the brain....
Veins of Head and Neck
On the other hand, the vertebral veins, unlike their arterial counterparts, are not primarily responsible for brain drainage. Instead, they drain the cervical vertebrae, spinal cord, and some small...
Anatomy of the Brain: Ventricles

