This study is a comparative study of the relationship between corneal structure, morphology, and function in a range of mammalian species. Xray scattering patterns were gathered at regular spatial intervals over the excised cornea (and in most cases also the scleral rim) of humans, marmosets, horses, cows, pigs, rabbits, and mice. All patterns were analyzed to produce quantitative information regarding the predominant orientation of fibrillar collagen throughout the tissue. The predominant direction of corneal collagen varies between mammals. This variation is not related to the size, shape, or thickness of the cornea or the frequency with which the animal blinks. A relationship does, however, appear to exist between corneal collagen arrangement and visual acuity. An excess of collagen directed toward one or both sets of opposing rectus muscles is a feature of animals that have an intermediate to high level of visual acuity. There is a significant variation in the arrangement of corneal collagen between different mammalian species. This finding may be related to differences in the frequency of action and the forces generated by the various extraocular muscles during eye movement and image fixation. Anat Rec, 290:1542Rec, 290: -1550Rec, 290: , 2007Rec, 290: . 2007 Wiley-Liss, Inc.

Changes in corneal thickness before and after eye opening are not caused by widespread alterations in the collagen fibrillar array but are more likely caused by expansion and contraction of regions devoid of regularly arranged collagen. The postnatal development of a corneal annulus of collagen, thought to play a role in stabilizing the curvature of the cornea, may be triggered by visual factors.

In this study 5-FU did not provoke an intraocular inflammatory response and had minimal effect on extraocular structures. Changes in corneal epithelium and endothelium detectable by confocal microscopy suggest a small toxic effect. These in vivo measurements by confocal microscopy were confirmed by SEM. Repeated administration did not cause additional cumulative toxic effects in the anterior segment. Therefore, multiple injections of 5- FU into the filtering bleb pose minimal risk to intraocular structures.

Purpose With the increasing use of minimally invasive surgical techniques for intraocular pressure (IOP) lowering in glaucoma patients, there is a need to examine best practices regarding the postoperative management of these patients. Corticosteroids, though effective in controlling postoperative ocular pain and inflammation, present distinct challenges in glaucoma surgery patients, as their use can be associated with IOP elevation. Loteprednol etabonate (LE) is an ocular corticosteroid designed to have an improved safety profile relative to other corticosteroids. Methods We report here a representative selection of cases in which patients were successfully treated with LE ophthalmic gel 0.5% (LE gel) following a variety of minimally invasive glaucoma surgery (MIGS) procedures. Cases included patients undergoing various procedures including a Trabectome combined with cataract surgery; micro-stent surgery (iStent) combined with cataract surgery; supraciliary CyPass Micro-Stent placement combined with cataract surgery; Kahook Dual Blade goniotomy; and ab interno canaloplasty using the iTrack catheter. Observations In all cases, use of LE gel during the postoperative period appeared effective and safe in reducing inflammation and controlling pain. No adverse events or IOP elevations were noted, even in those patients continuing use of LE gel past the postoperative period for longer than six months with documented follow-up. In two cases, patients with elevated IOP using either prednisolone or difluprednate postoperatively were switched to LE gel, with a subsequent reduction in IOP. Conclusions This selection of cases involving patients undergoing MIGS suggests that LE gel may be an effective and safe option for treating postoperative inflammation and pain following such procedures with minimal to no effect on IOP or other negative sequalae.