Abstract
Purpose :
Patients have lowering of intraocular pressure (IOP), post phacoemulsification cataract surgery. Histopathology studies reported trabecular meshwork (TM) changes in pseudophakic eyes with posterior chamber intraocular lens (PCIOL) and have eluted to the mechanisms for IOP decrease. In selected cases, an anterior chamber IOL (ACIOL) may be implanted. Unlike PCIOLs, TM changes following implantation of ACIOL have not been studied. This study aims to examine the histopathological changes in TM and corneal endothelium among eyes with ACIOL and PCIOL and compare them with phakic eyes.
Methods :
Thirty-five fixed post-mortem eyes with IOL implants and five phakic eyes of the MUHC-McGill University Ocular Pathology Laboratory were studied, along with relevant clinical information. The anterior segments were bisected and processed routinely. Slides were stained with Masson’s Trichrome and CD31 vascular endothelial antibody, and digitalized. Customized Medical Parachute TMAN software quantified the cellular components, the trabecular extracellular matrix (ECM), fibrosis and trabecular area on each slide. Schlemm’s Canal and corneal endothelium were quantified and compared across the phakic, PCIOL and ACIOL groups.
Results :
Cellular component of the TM were lower in the ACIOLs and PCIOLs compared to phakic eyes, however, significant only between PCIOL and phakic eyes (p=0.0023). ECM area component, TM fibrosis, and TM lamellae area and ciliary process fibrosis showed no differences (p=0.40, 0.99, 0.10, 0.83). CD31 stained Schlemm’s Canal endothelial cells, no differences between groups were seen (p=0.45). Significantly lower corneal endothelial cells were seen in ACIOLs compared to both PCIOLs and phakic eyes (P=0.0002).
Conclusions :
Anterior andposterior chamber IOLs demonstrated a loss of cellular components in the TM compared to the phakic eyes. PCIOLs displayed the least amount of TM cells. The ACIOLs led to a greater loss of corneal endothelial cells than PCIOLS and phakic eyes. The endothelial cells in Schlemm’s canal did not seem to be affected by the IOL placements. Therefore, the number of these endothelial cells probably does not play a role in the decrease of intraocular pressure seen in those patients.
This is a 2020 ARVO Annual Meeting abstract.