Yee RW, Matsuda M, Schultz RO, et al. Changes in the normal corneal endothelial cellular pattern as a function of age
ABSTRACT Human endothelial morphologic changes were quantitated by specular microscopy and computer-assisted morphometry to establish normal baselines of various morphologic parameters. Cellular polymegethism and cellular pleomorphism increases with age, and normal baseline parameters are detailed. Furthermore, no significant difference in any morphologic parameters between the right and left eye and between central and peripheral endothelium was detected in the normal corneas examined. These normal morphologic baselines can possibly be utilized to detect early corneal endothelial pathology and/or cell loss nondetectable by cell density measurement.
- SourceAvailable from: Allan Storr-Paulsen
[Show abstract] [Hide abstract]
- "This indicates that the surgery is more harmful to the endothelium probably due to more manipulation in the anterior chamber because of the floppy iris, use of iris hooks, etc. There were no significant differences in the percentage of hexagonal cells, CV or CCT, which implies equal and normal postoperative healing of the corneal endothelium in both study groups (Yee et al. 1985). This indicates that the higher cell loss in the tamsulosin group was not due to a toxic effect. "
ABSTRACT: Purpose: The purpose of this study was to assess the incidence of intraoperative floppy iris syndrome (IFIS) and the morphology of the corneal endothelium after cataract extraction in Caucasian male patients exposed to the α-1a adrenergic receptor antagonist tamsulosin. Methods: In a clinical prospective study, 23 male patients (23 eyes) treated with tamsulosin due to benign prostatic hyperplasia and 25 male patients (25 eyes) with no tamsulosin treatment had cataract surgery. The divide-and-conquer technique was used with the Infinity OZil(®) machine. A combination of Healon and Healon5 was used in all patients, but the use of additional Vision Blue, iris retractors or intracameral phenylephrine in the tamsulosin group was at the discretion of the surgeon. The endothelial cell density, variation in endothelial cell size (CV), percentage of hexagonal cells and central corneal thickness (CCT) were recorded at baseline and at 3 months postoperatively. Results: In the tamsulosin-treated group, 19 of 23 eyes (83%) developed IFIS, compared with no IFIS in the control group. Compared with the control group, the tamsulosin group showed significantly less dilatation at the start of the operation, significant miosis during surgery and significantly greater corneal endothelial cell loss 3 months postoperatively (12% versus 3%; p < 0.001). Conclusion: Intraoperative floppy iris syndrome during cataract surgery is significantly associated with tamsulosin-treated male patients. Patients on tamsulosin showed less preoperative dilatation, significant miosis during surgery, and had significantly greater postoperative endothelial cell loss compared with nontreated patients despite recommended precautions.Acta ophthalmologica 04/2013; 92(4). DOI:10.1111/aos.12140 · 2.51 Impact Factor
[Show abstract] [Hide abstract]
- "ª 2010 The Authors Journal compilation ª 2010 Acta Ophthalmol doi: 10.1111/j.1755-3768.2010.01974.x Acta Ophthalmologica 2010 Morphometric variables of the corneal endothelium such as cell density, sometimes referred to as average cell size and cell size variation, usually expressed as coefficient of variation for cell size, are frequently analysed (Bursell et al. 1981; Lester et al. 1981; Schimmelpfennig 1984; Yee et al. 1985). Presently, morphometric variables of the corneal endothelium are most commonly estimated by CSM (Sturrock et al. 1978; Rao et al. 1982; Stur & Grabner 1983; Hartmann & Koditz 1984; Hirst et al. 1984; Glasser et al. 1985a,b; Hartmann et al. 1985; Matsuda et al. 1986; Siertsema et al. 1993). "
ABSTRACT: The current simulator is a further development of previously published work on emulation of cell structure (Honda 1978; Weliky & Oster 1990; Fitzke et al. 1997; Meineke et al. 2001; Sanchez-Marin 2005; Bucht et al. 2006). The algorithm in the current study is in every part a new development but based on experience gathered from application of previously published algorithms. We here included generation of the cell structure by automated randomization with fully defined resulting cell morphometry parameters for each individual cell in each image simulated. This is necessary to simulate realistic unbiased images. The randomization makes it impossible to set exact morphometric characteristics of an image before it has been created. It is only possible to preset the mean level of the cell density and the variation of cell size, respectively. Pleomorphism and polymegethism are related in the simulator as are they in real-life corneal endothelium (Doughty 1998). The problem of not knowing beforehand the exact outcome of morphometric parameters because of the randomization is made up for by the ability to automatically create literally thousands of images, and each image is, once generated with randomization, calculated for morphometrical characteristics. Thus, a subset of generated images with specified morphometric characteristics can secondarily be selected for any strategy for specific morphometric analysis.Acta ophthalmologica 05/2011; 89(3):e242-50. DOI:10.1111/j.1755-3768.2010.01974.x · 2.51 Impact Factor
[Show abstract] [Hide abstract]
- "Preoperatively, demographic as well as endothelial cell parameters were similar in the three groups, indicating that no sampling bias was present. Loss of endothelial cells is compensated by cellular enlargement, cell gliding, rearrangement and cell coalescence (Mishima 1982; Yee et al. 1985). Specular microscopy should be performed at least 3 months postoperatively , when this reorganization has stabilized (Schultz et al. 1986). "
ABSTRACT: To compare the ability of cohesive and dispersive ophthalmic viscoelastic devices (OVDs) to protect the corneal endothelium following in-the-bag phacoemulsification with implantation of a foldable posterior chamber intraocular lens (IOL). In a prospective single-masked randomized study, 60 eyes of 60 cataract patients were assigned to three groups of 20 patients each, according to which OVD was used: Celoftal, Vitrax or Healon. The corneal response to surgery was evaluated by measuring the endothelial cell loss, the variation in mean cell area of the endothelial cells (CV), the frequency of hexagonal cells, and the central corneal thickness. Data were recorded preoperatively and 3 months postoperatively. Preoperatively, no significant difference was observed in cell count, CV, hexagonal pattern or pachymetry among groups. Postoperatively, all three groups had a significant decrease in cell count, but the decrease was significantly less in the Vitrax group (6.97%) than in the Celoftal (18.03%) and Healon groups (18.46%). No changes in CV, hexagonality or corneal thickness were observed within any of the three groups or among the groups. There was an equal and significant increase in visual acuity. Phacoemulsification with implantation of a posterior chamber lens is known to affect the density and morphology of corneal endothelial cells. Viscoelastics facilitate cataract surgery and protect the corneal endothelium during the procedure. Choosing a dispersive hyaluronate OVD during the phaco procedure may allow for protection of the endothelial cells while suppressing the formation of free radicals. This may be the reason for the superior protective effect on the corneal endothelial cells of Vitrax compared with Celoftal and Healon.Acta Ophthalmologica Scandinavica 04/2007; 85(2):183-7. DOI:10.1111/j.1600-0420.2006.00784.x · 1.85 Impact Factor