Comparison of dynamic vault changes following implantation of two different models of phakic intraocular lenses.

Eyecryl phakic or Eyecryl phakic toric IOL and Visian implantable collamer lens are posterior chamber phakic intraocular lens (pIOL) that have been reported to be safe and effective surgical option for correction of moderate to high myopia , hyperopia and astigmatism. Vault is the distance between anterior surface of crystalline lens and posterior surface of phakic iol. Low vault may lead to mechanical contact with the crystalline lens , which is responsible for high incidence of anterior capsular opacification and cataract formation. Conversely , excessively high vault causes mechanical contact between the pIOL and iris, resulting in inflammation , high intraocular pressure, angle closure glaucoma and pigment dispersion syndrome. As both models of pIOL are made up of different material , it will be interesting to evaluate the vault height in both brands in varying light conditions. In this is a prospective comparative  study we aim to compare the difference in dynamic vault between two lenses owing to difference in their material.