Optic Nerve Head Biomechanic and IOP Changes Before and After the Injection of Aflibercept for Neovascular Age-Related Macular Degeneration

Abstract

A significant widening and deepening of the optic cup, BMO expansion, and prelaminar tissue thinning occurred following IAI for neovascular AMD. Eyes having greater optic disc cup deepening and prelaminar tissue condensation after IAI, associated with a lower IOP increase after injection, suggesting that ONH compliance might buffer the effect of additional intravitreal fluid injection on IOP values.

Lamina cribrosa position and Bruch’s membrane opening differences between anterior ischemic optic neuropathy and open-angle glaucoma

“…On the other hand, BMO expansion has been demonstrated immediately after intravitreal aflibercept injection 24 and in NAION eyes at onset that reversed with the follow-up. 36 ONH deformation by means of an IOP increase or optic nerve swelling can be explained by two mechanisms or forces; one pushing LC backwards and compressing the PT and other related to the hoop stress (inner circumferential pressure supported by the peripapillary sclera) which results in the sclera and BMO expansion.…”

“…Histological, experimental, and clinical studies have shown morphological changes in the ONH after artificial induction of IOP elevation, including an increase in ONH excavation, a decrease in PTT, and a backward LC displacement, suggesting that the ONH has viscoelastic properties. 24–29 In contrast, a forward LC displacement and PT thickening have been observed following medical or surgical reduction of IOP. 30–32…”

“…Three equidistant points (inferior, middle, and superior), corresponding to one-half and one-third of the reference, were highlighted and connected from this reference line to the anterior face of the prelaminar tissue (PT) and the anterior surface of the LC. 24…”

Influence of Chronic Ocular Hypertension on Emmetropia: Refractive, Structural and Functional Study in Two Rat Models

“…Indeed, there is increasing evidence about the development of delayed and sustained OHT associated with repeated intravitreal anti-vascular endothelial growth factor injections in retinal diseases, such as age-related macular degeneration [59,60]. Several structure optic nerve head manifestations after intravitreal volume injections have been lately described as a mechanical displacement of the optic nerve head and canal expansion, with a widening and deepening of the optic, a prelaminar tissue thinning and a Bruch membrane opening expansion, suggesting structural changes after IOP and volume increase in aged patients, with rigid sclera [61]. Our experiments started when the rats were 4 weeks old, so they should not be considered either adults or newborns, but young rats.…”

Brain Health Assessment in Macular Degeneration Patients Undergoing Intravitreal Anti–vascular Endothelial Growth Factor Injections (The Bham Study)

“…Acute optic cup changes are noted post-IVI, with an increased deepening and widening of the optic cup, along with expansion of the Bruch membrane opening within 5 minutes of IVI. 4 Repeated IVI also increased optic nerve cupping. 5 Although there is no evidence to suggest that these changes alter VRCC-CNS barriers, they do confirm that repeated IVI can cause anatomical changes at the interface of these barriers.…”