Comparison of 2 types of intrastromal corneal ring segments for keratoconus.
OBJECTIVE
To assess the effectiveness and safety of 2 types of 6.0 mm intrastromal corneal ring segments (ICRS) in patients with mild to severe keratoconus.


METHODS
Lebanese American University, Beirut, Lebanon.


METHODS
Retrospective comparative case series.


METHODS
Eyes had implantation of Intacs SK ICRS (Group 1) or Keraring SI6 ICRS (Group 2). Visual acuity (logMAR), refraction, keratometry, and higher-order aberrations were compared 6 months and 1 year postoperatively.


RESULTS
Group 1 comprised 66 eyes and Group 2, 107 eyes. The groups were comparable preoperatively. One-year postoperatively, the mean uncorrected distance visual acuity improved by 0.62 logMAR ± 0.19 (SD) in Group 1 and by 0.67 ± 0.17 logMAR in Group 2 (P=.211). The mean corrected distance visual acuity improved by 0.12 ± 0.11 logMAR and by 0.08 ± 0.13, respectively (P=.301). The spherical equivalent decreased by a mean of 2.80 ± 2.87 D and 2.65 ± 3.00 D, respectively (P=.572). Keratometry (K) flat and K steep decreased by a mean of 1.51 ± 1.57 D and 2.24 ± 1.61 D, respectively, in Group 1 and by 1.10 ± 2.00 D and 1.44 ± 1.64 D, respectively, in Group 2 (P=.667 and P=.184, respectively). Primary coma root mean square decreased by a mean of 1.09 ± 0.66 μm in Group 1 and 0.99 ± 0.72 μm in Group 2 (P=.716).


CONCLUSIONS
Both ICRS models significantly improved visual function in patients with keratoconus, with comparable postoperative profiles and no major complications.


BACKGROUND
No author has a financial or proprietary interest in any material or method mentioned.
Ophthalmic Consultants of Beirut, Laser Vision Center, and Lebanese American University, Beirut, Lebanon.
Walid
W
Haddad
Ali
A
Fadlallah
Ali
A
Dirani
Hala
H
El Rami
Daoud
D
Fahd
Dana
D
Khanafer
Sharbel
S
Fahed
D000328:Adult; D003319:Corneal Stroma / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography; D057108:Corneal Wavefront Aberration / Q000503:physiopathology; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D019904:Polymethyl Methacrylate; D011183:Postoperative Complications; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology
D019904:Polymethyl Methacrylate