• Outflow facility was measured in human eye bank eyes following penetrating keratoplasty (PKP) and cataract extraction. After measuring baseline outflow facility, a PKP and lens extraction was performed with the corneal button replaced by both interrupted "through-and-through" sutures and a conventional mid-to-deep stromal running suture. Outflow facility was unchanged from baseline with both sutures. However, following removal of through-and-through sutures outflow facility decreased 37%. This same suturing procedure was repeated in a second group of phakic eyes in which suture depth did not influence outflow facility.
Zimmerman TJ, Krupin T, Grodzki W, Waltman SR. The Effect of Suture Depth on Outflow Facility in Penetrating Keratoplasty. Arch Ophthalmol. 1978;96(3):505-506. doi:10.1001/archopht.1978.03910050273018