Macular Metrics Predict Function in Glaucoma With Prelaminar Schisis of the ONH

Assessment of the functional status of eyes with advanced glaucoma should differ on the basis of optic nerve head (ONH) prelaminar schisis, according to results of a study published in the American Journal of Ophthalmology.

A team of researchers conducted a cross-sectional study to investigate the clinical characteristics of ONH prelaminar schisis in the eyes of patients with advanced glaucoma. They retrospectively reviewed medical records from patients (116 eyes from 116 patients) with advanced glaucoma who visited the Chonnam National University Hospital in South Korea between 2019 and 2020. All patients underwent complete ophthalmic examinations, including spectral-domain optical coherence tomography.

The mean age of the patients was 62.64±13.21 years, 71.55% were men, and ONH prelaminar schisis was identified in 41.38% of the eyes.

ONH prelaminar schisis often presented as a splitting of the superficial prelaminar tissue with floating retinal vessels. Bilateral ONH prelaminar schisis was observed among 35 patients, of whom 33 also had bilateral glaucoma.

The investigators observed prelaminar schisis among a population of patients who were older (P <.001), with shorter axial lengths (P <.001); thinner lamina cribrosa (P =.004); deeper lamina cribrosa (P =.014); and greater macular ganglion cell layer thickness (P =.001), macular inner plexiform layer thickness (P =.001), and total macular thickness (P <.001).

Prelaminar schisis was associated with axial length per millimeter (adjusted odds ratio [aOR], 0.477; 95% CI, 0.280-0.813; P =.006), lamina cribrosa depth per micron (aOR, 1.003; 95% CI, 1.000-1.006; P =.041), and lamina cribrosa thickness per micron (aOR, 0.983; 95% CI, 0.965-0.999; P =.042).

There was a general trend for functional parameters to be associated with global Bruch’s membrane opening-minimum rim width, peripapillary retinal nerve fiber layer thickness, and macular thickness. In subgroup analyses, the relationship between structural and functional parameters were less strong among patients with ONH prelaminar schisis.

This study may have been limited by not including visualization of the posterior vitreous or quantification of the degree of ONH prelaminar schisis.

The study authors concluded that ONH prelaminar schisis in patients with advanced glaucoma is associated with thin and deep lamina cribrosa with short axial lengths and a thick macula. These changes appeared to affect the relationship between structure and function and may indicate that assessing eye health among patients with advanced glaucoma and ONH prelaminar schisis should be based on macular parameters.

In addition, because they could not identify the temporal relationship between ONH prelaminar schisis and several important clinical parameters, the researchers recommended that longitudinal studies be conducted to clarify these relationships.

Reference

Sung MS, Jin HN, Park SW. Clinical features of advanced glaucoma with optic nerve head prelaminar schisis prelaminar in advanced glaucoma. Am J Ophthalmol. Published online June 18, 2021. doi:10.1016/j.ajo.2021.06.007