Reduced Pulsatile Trabecular Meswork Motion Helps Identify Outflow Pathway Changes

close up head of young patient fix in Tomography in Optical Coherence (OCT) equipment.
A study explores how imaging the pulsatile trabecular meshwork motion may provide new insights into glaucoma pathophysiology.

Pulsatile trabecular meshwork motion was reduced in primary open-angle glaucoma (POAG) cases compared with patients without glaucoma with phase-sensitive optical coherence tomography (PhS-OCT) — possibly because of altered tissue stiffness or other trabecular meshwork (TM), according to a study in Investigative Ophthalmology & Visual Science.

“Our evidence suggests that the measurement of pulsatile TM motion with PhS-OCT may help in characterizing outflow pathway abnormalities,” according to investigators.

The cross-sectional study looked at 16 eyes of 8 healthy subjects and 18 eyes of 9 participants with POAG. Researchers used a laboratory-based prototype PhS-OCT system to measure pulsatile TM motion, and those images were analyzed to find the parameters of pulsatile TM motion (ie, maximum velocity [MV] and cumulative displacement [CDisp]). Pneumotonography measured outflow facility and ocular pulse amplitude. Investigators compared detection sensitivity in various parameters using the area under the receiver operating characteristic curves (AUCs).

The study found a pulsatile TM motion waveform synchronous with digital pulse using PhS-OCT in healthy and POAG eyes. 

“The mean MV in eyes with glaucoma was significantly lower than in healthy eyes (P <.001),” the study shows. “The mean CDisp in POAG eyes was also significantly lower than in healthy eyes (P <.001). CDisp showed a significant correlation (P =.0088) with ocular pulse amplitude in the study. Compared with the outflow facility, both the MV and CDisp were found to have better discrimination of glaucoma (P <.001 and P =.0074, respectively).”

One limitation of the study is its small sample size, but the results show further study is needed. Another limitation was that POAG subjects were on glaucoma medications, which change pressure as well as the biomechanics related to TM motion.

Disclosure: One study author declared affiliations with the biotech or pharmaceutical industries. Please see the original reference for a full list of authors’ disclosures.


Gao K, Shaozhen Song S, Johnstone MA, et al. Reduced pulsatile trabecular meshwork motion in eyes with primary open angle glaucoma using phase-sensitive optical coherence tomography. Invest Ophthalmol Vis Sci. 2020;61(14):21. doi:10.1167/iovs.61.14.21.