• Written By:
    Cataract/Anterior Segment, Pediatric Ophth/Strabismus

    Review of: Osmotically induced removal of lens epithelial cells to prevent PCO after pediatric cataract surgery: Pilot study to assess feasibility

    Zhang J, Hussain A, Yue S, et al. Journal of Cataract & Refractive Surgery, , October 2019

    Researchers describe a new preventive method to mitigate posterior capsule opacification after cataract surgery in children.

    Study design

    This laboratory pilot study—conducted in Shanghai, China—involved the development of an osmotic-shock technique to remove lens epithelial cells (LECs) as a preventive measure for post-surgery posterior capsule opacification. Human LECs were prepared by cultures on coverslips/collagen-coated membrane inserts, human lens capsule biopsies and lens organ cultured models of posterior capsule opacification. The tissues were subjected to single or incremental hyperosmotic shock (NaCl, 350–4,000 mOsm/L) in the presence of Na+-K+-2Cl− cotransporter (NKCC) inhibitors to disable the regulatory volume increase process. The integrity of the cell monolayer was then determined.

    Outcomes

    This method was effective in rapidly detaching LECs from their basement membranes. Hyperosmotic shock (400 mOsm/L) caused cells to shrink within 5 minutes. However, in the absence of the NKCC inhibitor, the shrunken cells returned to original cell volume and architecture. Inhibition of the regulatory volume increase process led to persistent cell shrinkage and cell detachment from the underlying support medium.

    Limitations

    The technique is not ready for clinical prime time. Safe and optimal exposure time to the hyperosmotic agent has yet to be determined. Consideration must also be given to the strength of the hyperosmotic shock to avoid collateral damage to adjacent tissues in case of accidental leakage of the solution.

    Clinical significance

    Pediatric posterior capsular opacification caused by LEC proliferation and migration occurs following nearly every case of pediatric cataract surgery. So far, there is no cure for this condition; the only option is the preventive measure of performing primary posterior capsulotomy at the time of cataract extraction. Use of this new osmotic-shock method could save some children—specifically those who cannot sit for Nd:YAG laser capsulotomy—from having to have repeat posterior capsule operations under general anesthesia.