TY - JOUR
T1 - Efficacy of intacs intrastromal corneal ring segment relative to depth of insertion evaluated with anterior segment optical coherence tomography
AU - Hashemi, Hassan
AU - Yazdani-Abyaneh, Alireza
AU - Beheshtnejad, Amirhushang
AU - Jabbarvand, Mahmood
AU - Kheirkhah, Ahmad
AU - Ghaffary, Seyed Reza
PY - 2013
Y1 - 2013
N2 - Aim: To evaluate the effect of implantation depth of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, California) on visual and topographic outcomes in patients with post- laser-assisted in situ keratomileusis (LASIK) ectasias. Settings and Design: Retrospective, observational case series. Materials and Methods: In this case series, 16 eyes of 12 patients were evaluated. All cases were post-LASIK ectasia that had undergone intrastromal corneal ring segment (ICRS) implantation. The planned insertion depth was 70% of stromal thickness using a manual dissector. At least 12 months postoperatively, all eyes underwent Visante (Carl Zeiss Meditec) AS-OCT to determine insertion depth. Cases were categorized into 3 groups based on the measured implantation depth: 40-59% thickness; 60-79% thickness; and =80% thickness. Visual, refractive and topographic outcomes were evaluated relative to implantation depth. Results: The lowest improvement in the study parameters ocurred when the implantation depth was =80%. In this group, uncorrected visual acuity (UCVA) and best spectacle corrected VA (BSCVA) improved less than 0.5 lines. Manifest refractive spherical equivalent (MRSE) and mean keratometry (Km) change was less than 0.5 diopters (D). The greatest improvements were observed with implantation depth of 60-79% where UCVA and BSCVA increased by 4.5 and 2.5 lines respectively, and MRSE and Km changed by approximately 2.00 D. Less improvement was found when ICRS were implanted between 40-59% of stromal thickness. Conclusion: Implantation of ICRS greater than 80% of stromal thickness may have no effect on visual and topographic status.
AB - Aim: To evaluate the effect of implantation depth of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, California) on visual and topographic outcomes in patients with post- laser-assisted in situ keratomileusis (LASIK) ectasias. Settings and Design: Retrospective, observational case series. Materials and Methods: In this case series, 16 eyes of 12 patients were evaluated. All cases were post-LASIK ectasia that had undergone intrastromal corneal ring segment (ICRS) implantation. The planned insertion depth was 70% of stromal thickness using a manual dissector. At least 12 months postoperatively, all eyes underwent Visante (Carl Zeiss Meditec) AS-OCT to determine insertion depth. Cases were categorized into 3 groups based on the measured implantation depth: 40-59% thickness; 60-79% thickness; and =80% thickness. Visual, refractive and topographic outcomes were evaluated relative to implantation depth. Results: The lowest improvement in the study parameters ocurred when the implantation depth was =80%. In this group, uncorrected visual acuity (UCVA) and best spectacle corrected VA (BSCVA) improved less than 0.5 lines. Manifest refractive spherical equivalent (MRSE) and mean keratometry (Km) change was less than 0.5 diopters (D). The greatest improvements were observed with implantation depth of 60-79% where UCVA and BSCVA increased by 4.5 and 2.5 lines respectively, and MRSE and Km changed by approximately 2.00 D. Less improvement was found when ICRS were implanted between 40-59% of stromal thickness. Conclusion: Implantation of ICRS greater than 80% of stromal thickness may have no effect on visual and topographic status.
KW - Intacs implantation depth
KW - Laser-assisted in situ Keratomileusis
KW - Optical coherence tomography
KW - Post-lasik ectasia
KW - Visual Acuity
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U2 - 10.4103/0974-9233.114800
DO - 10.4103/0974-9233.114800
M3 - Article
C2 - 24014988
AN - SCOPUS:84888167157
SN - 0974-9233
VL - 20
SP - 234
EP - 238
JO - Middle East African Journal of Ophthalmology
JF - Middle East African Journal of Ophthalmology
IS - 3
ER -