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Victor Garcia Bennett
In the current literature of Descemet’s membrane endothelial keratoplasty (DMEK) little is known about the exact behaviour of the intraocular bubble in the post- operative period although it plays a crucial roll in the correct adherence and healing of the patient’s graft. This Thesis has characterized said bubble, by taking as representative its projection on the cornea, using computational fluid dynamics. Its shape, size and position as well as the percentage of the donor’s graft being covered have been totally described as a function of the patient’s anterior chamber geometry, two-degree-of-freedom position and post-operative period, with a series of simple coefficients.
As an output of the research, the results are available in different forms for their clinical use. A priori formats such as contour graphs, time-averages and tables have been given to have insight about the consequences of certain decisions over the graft coverage after DMEK. A posteriori designs are also proposed such as heatmaps which can be utilized after the post-operative period to asses the quality of the treatment.
It has been shown that for small anterior chambers –especially in phakic eyes- the surgeon’s ability to inject the correct amount of gas dominates over what the patient can do with his or her position. However, as the size of the anterior chamber increases -especially in pseudophakic eyes– the position of the patient gains impor- tance. Although different post-operative scenarios have been studied, if the patient is lying down facing up s/he will achieve an almost optimal graft coverage. How- ever, this compromise does not always yield a homogeneous gas contact over all the graft, hindering the bottom quadrants. To resolve this situation, the given optimal positioning should be pursued. Monitoring the position becomes more critical as the anterior chamber increases and for patients with pseudophakic eyes, while more relaxed measures could be applied to small -especially phakic- anterior chambers.