Large-diameter deep anterior lamellar keratoplasty for keratoconus: visual and refractive outcomes

Abstract

Chinese Clinical Trial Registry (TRC-13003122).

Single-piece femtosecond-assisted mushroom keratoplasty in children

“…13,[18][19][20] The large 9 mm anterior lamella used in this technique also provides a refractive advantage by reducing the chance of inducing significantly high-degree astigmatism. 2 Our case series included patients from 8 to 17 years of age, and none of the cases required amblyopia treatment. The fast visual recovery and spectacle-correctable postoperative astigmatism could potentially also be an advantage for younger children, and the advantage might include an earlier possibility to treat amblyopia.…”

“…Large-diameter PKP has the advantage of improved refractive outcome compared to small-diameter PKP, but it carries a greater risk of immunologic rejection. [2][3][4] Small-diameter PKPs are less likely to experience immunologic events but carry an increased risk of poor visual outcome due to high-degree postoperative astigmatism. [5][6][7] In 2003 Busin and colleagues 8 described a two-piece microkeratome-assisted mushroom keratoplasty technique in which a two-piece donor tissue consisting of a 9 mm top hat and a 6 mm posterior stem was placed in a manually dissected recipient cornea.…”

How to Improve Visual Acuity in Keratoconic Cornea?

“…The objective of the corneal transplant is to achieve an acceptable visual acuity with a minimum of retraction error and with a long duration. DALK was introduced by Eduardo Archila in 1984 [39]; it is a very innovative technique indicated for patients who have no compromise of the corneal endothelium or Descemet's membrane and for mild cases of keratoconus [40][41][42][43][44][45].…”

“…Few of the advantages of this technique over penetrating keratoplasty (PKP) are the preservation of the host's endothelium; a low rate of graft rejection; minimal loss of endothelial cells; lower postsurgical risk; a short term of steroid use during the postoperative period, reducing complications such as cataract, glaucoma, and late wound healing; and lower risk of intraocular infections; adding to this, Romano et al [45] refer that it produces a stronger cornea, being less prone to spontaneous or posttraumatic wounds, as well as a longer graft survival than PKP [39,43,44,47].…”

“…However, a fairly long learning curve is required, since the technique can be complicated for some surgeons, and the surgery time is longer than PKP; it also has unpredictable visual results compared to PKP since it takes between 6 and 12 months to reach an acceptable visual acuity and generate high degrees of spherical and astigmatic refractive errors, and this depends on the thickness of the stromal bed or the presence of folds in the Descemet's membrane; there may also be graft tears that require conversion to PKP [42][43][44][45][46].…”