TY - JOUR
T1 - ICR® (Intrastromal Corneal Ring) astigmatism arcs for the correction of corneal astigmatism
T2 - An eyebank study
AU - Verity, Steven
AU - Ito, Mitsutoshi
AU - Quantock, Andrew J.
AU - Frankel, Roddy
AU - Schanzlin, David J.
PY - 1996/2/15
Y1 - 1996/2/15
N2 - Purpose. To evaluate the effect of pairs of ICR arcuate segments on corneal astigmatism. Methods. Human donor eyes, less than 48 hours postmortem, were thinned in dextran to a paracentral corneal thickness between 550 μm and 650 μm. A standard ICR stromal channel was generated at two-thirds stromal depth, and pairs of arcuate segments of various dimensions were implanted at opposite sides of the circular dissection. We used 10-degree, 45-degree and 60-degree arcs with thicknesses of 0.30 mm, 0.35 mm and 0.40 mm. Preoperative and postoperative computer-assisted topographic analysis (EyeSys Technologies, Inc., Houston, TX., software version 2.108) was performed to assess the refractive effect. Results. Steepening was observed in the meridian in which the arcs had been placed with concomitant corneal flattening in the meridian orthogonal to arc placement. Topographic averaging analyses with standard deviation data were generated and displayed in color-coded maps in a manner similar to standard topographic maps. Keratorefractive effect, assessed as the extent of topographic shift, was proportional to both arcuate segment length and thickness. Conclusions. ICR Astigmatism Arcs may be effective for the treatment of corneal astigmatism.
AB - Purpose. To evaluate the effect of pairs of ICR arcuate segments on corneal astigmatism. Methods. Human donor eyes, less than 48 hours postmortem, were thinned in dextran to a paracentral corneal thickness between 550 μm and 650 μm. A standard ICR stromal channel was generated at two-thirds stromal depth, and pairs of arcuate segments of various dimensions were implanted at opposite sides of the circular dissection. We used 10-degree, 45-degree and 60-degree arcs with thicknesses of 0.30 mm, 0.35 mm and 0.40 mm. Preoperative and postoperative computer-assisted topographic analysis (EyeSys Technologies, Inc., Houston, TX., software version 2.108) was performed to assess the refractive effect. Results. Steepening was observed in the meridian in which the arcs had been placed with concomitant corneal flattening in the meridian orthogonal to arc placement. Topographic averaging analyses with standard deviation data were generated and displayed in color-coded maps in a manner similar to standard topographic maps. Keratorefractive effect, assessed as the extent of topographic shift, was proportional to both arcuate segment length and thickness. Conclusions. ICR Astigmatism Arcs may be effective for the treatment of corneal astigmatism.
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M3 - Article
AN - SCOPUS:8544280385
SN - 0146-0404
VL - 37
SP - S573
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 3
ER -