Mathematical and computer simulation modelling of intracameral forces causing pupil block due to air bubble use in Descemet's Stripping Endothelial Keratoplasty: the mechanics of iris buckling.

Background: Descemet's Stripping Endothelial Keratoplasty has been associated with a steep learning curve. Angle closure post Descemet's Stripping Endothelial Keratoplasty has been reported, either because of air posterior to the iris causing iridocorneal adhesions, or by air anterior to the iris causing pupillary block. The mechanics of floppy iris syndrome and pupil block have not been discussed.

Repeatability of a novel technique for in vivo measurement of three-dimensional patellar tracking using magnetic resonance imaging.

Purpose: To determine the repeatability of a novel noninvasive MRI-based technique for measuring patellofemoral kinematics in vivo.

Materials And Methods: The patellar kinematics measurement method relies on registering bone models (with associated coordinate systems) developed from a high resolution MRI scan to loaded bone positions derived from fast, low resolution MRI scans. The intrasubject variability, high resolution to low resolution registration error, and interexperimenter repeatability were quantified in experiments on three healthy subjects.