TY - JOUR
T1 - Decision making nomogram for intrastromal corneal ring segments in keratoconus
AU - Shetty, Rohit
AU - D'Souza, Sharon
AU - Ramachandran, Sarika
AU - Kurian, Mathew
AU - Nuijts, Rudy M. M. A.
PY - 2014/1
Y1 - 2014/1
N2 - Purpose: To create a nomogram for the insertion of intrastromal corneal ring segments (ICRS) (Intacs (R)) in eyes with keratoconus. Setting: Tertiary eye care center in South India. Materials and Methods: This prospective, non-randomized, interventional case series used a self-designed decision-making nomogram for the selection of ICRS in keratoconus patients based on the centration of the cone, mean refractive spherical equivalent (MRSE), and mean keratometry (Km) values. The 3, 6, and 12 months clinical outcomes were compared to historical controls. Primary endpoints were improvement in uncorrected and best-corrected vision and change in the keratometric values. Results: Group A comprised of 52 eyes of 50 patients that followed the nomogram, while Group B comprised of 25 eyes of 23 non-nomogram historical controls matched for baseline parameters. In Group A, the uncorrected distance visual acuity (UDVA) improved from 0.16 +/- 0.15 to 0.25 +/- 0.16 (P <0.001), corrected distance visual acuity (CDVA) from 0.58 +/- 0.2 to 0.69 +/- 0.21 (P = 0.022), MRSE from -5.41 +/- 4.94 to -1.71 +/- 2.88 (P <0.001), Km from 51.77 +/- 5.45 to 48.63 +/- 4.37 (P <0.001), and astigmatism reduced from 5.86 +/- 2.61 to 4.91 +/- 2.72 diopters (P <0.001). In Group B, improvement in the average MRSE was from -6.44 +/- 5.32 to -3.26 +/- 2.82 (P <0.013) and in the average Km from 53.64 +/- 5.32 to 50.31 +/- 5.02 (P <0.001). Other parameters did not improve significantly. A statistically significant difference was present in the percentage of patients achieving a good clinical outcome between the two groups (P <0.001; Chi-square). Conclusion: The nomogram provides a means to choose the appropriate ICRS, hence improving the outcome in patients with keratoconus.
AB - Purpose: To create a nomogram for the insertion of intrastromal corneal ring segments (ICRS) (Intacs (R)) in eyes with keratoconus. Setting: Tertiary eye care center in South India. Materials and Methods: This prospective, non-randomized, interventional case series used a self-designed decision-making nomogram for the selection of ICRS in keratoconus patients based on the centration of the cone, mean refractive spherical equivalent (MRSE), and mean keratometry (Km) values. The 3, 6, and 12 months clinical outcomes were compared to historical controls. Primary endpoints were improvement in uncorrected and best-corrected vision and change in the keratometric values. Results: Group A comprised of 52 eyes of 50 patients that followed the nomogram, while Group B comprised of 25 eyes of 23 non-nomogram historical controls matched for baseline parameters. In Group A, the uncorrected distance visual acuity (UDVA) improved from 0.16 +/- 0.15 to 0.25 +/- 0.16 (P <0.001), corrected distance visual acuity (CDVA) from 0.58 +/- 0.2 to 0.69 +/- 0.21 (P = 0.022), MRSE from -5.41 +/- 4.94 to -1.71 +/- 2.88 (P <0.001), Km from 51.77 +/- 5.45 to 48.63 +/- 4.37 (P <0.001), and astigmatism reduced from 5.86 +/- 2.61 to 4.91 +/- 2.72 diopters (P <0.001). In Group B, improvement in the average MRSE was from -6.44 +/- 5.32 to -3.26 +/- 2.82 (P <0.013) and in the average Km from 53.64 +/- 5.32 to 50.31 +/- 5.02 (P <0.001). Other parameters did not improve significantly. A statistically significant difference was present in the percentage of patients achieving a good clinical outcome between the two groups (P <0.001; Chi-square). Conclusion: The nomogram provides a means to choose the appropriate ICRS, hence improving the outcome in patients with keratoconus.
KW - Intacs
KW - keratoconus
KW - nomogram
U2 - 10.4103/0301-4738.126170
DO - 10.4103/0301-4738.126170
M3 - Article
C2 - 24492498
SN - 0301-4738
VL - 62
SP - 23
EP - 28
JO - Indian Journal of Ophthalmology
JF - Indian Journal of Ophthalmology
IS - 1
ER -