Effects of viscoelastic injection into Schlemm’s canal in primate and human eyes: Potential relevance to viscocanalostomy
Section snippets
Primate eyes
Postmortem eyes of Macaca nemestrina, six females and one male ages 9 to 14.5 years, were obtained immediately after the animals were killed for unrelated research. The eyes were dissected to a limbal ring encompassing SC and associated tissues. This limbal tissue was either cut into quarters or hemisected. A single suture was placed at the distal end of the tissue section, closing one end of SC. The suture was used to more closely approximate the situation in the living eye; viscoelastic entry
Primate eyes
In regions of both cannulation and viscoelastic injection, marked dilation of SC was seen (Fig 2A–C). In cannulated sections, the walls of SC were disrupted, and no structures were noted within SC (Fig 2B). In the proximal portion just beyond the cannula, where hydrostatic pressure from the viscoelastic would be expected to be the greatest, there was evidence of disruption of the endothelial lining of the anterior and posterior walls of SC (Fig 2D). In some areas there was also splitting into
Discussion
The desire to avoid trabeculectomy complications underlies the current interest in alternative surgeries for lowering intraocular pressure. Trabeculectomy, a guarded filtration surgery, is the most commonly used surgical technique for lowering intraocular pressure. Short-term complications of trabeculectomy related to anterior chamber entry such as hypotony, shallow or flat anterior chamber, choroidal detachments, and hemorrhage, can generally be avoided by tighter flap closures and modulation
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