Steep keratometry and central pachymetry after corneal collagen cross-linking procedure in patients with keratoconus

Mirko Resan; Miroslav Vukosavljević; Elisaveta Stanić; Bojan Kovač; Dragana Ristić; Maja Petrović; Brigitte Pajić-Eggspuehler; Bojan Pajić

doi:10.2298/VSP171024074R

Mirko Resan Military Medical Academy, Eye Clinic, Belgrade, Serbia
Miroslav Vukosavljević Military Medical Academy, Eye Clinic, Belgrade, Serbia
Elisaveta Stanić Special Ophthalmic Hospital „Milmedic“ Belgrade, Serbia
Bojan Kovač Military Medical Academy, Eye Clinic, Belgrade, Serbia
Dragana Ristić Military Medical Academy, Eye Clinic, Belgrade, Serbia
Maja Petrović Clinical Center of Niš, Eye Clinic, Niš, Serbia
Brigitte Pajić-Eggspuehler Eye Clinic ORASIS, Swiss Eye Research Foundation, Reinach AG, Switzerland
Bojan Pajić University of Defence, Faculty of Medicine of the Military Medical Academy, Belgrade, Serb

DOI: https://doi.org/10.2298/VSP171024074R

Keywords: keratoconus, corneal topography, corneal pachymetry, collagen

Abstract

Background/Aim. Keratoconus is a disorder of the eye
which results in progressive thinning of the cornea. The
cross-linking procedure (CXL) is applied in the treatment of
initial progredient forms of keratoconus. It is aiming at increasing
biomechanical stability of corneal stromal tissue to
slow down or stop progressing the ectatic disorder. The aim
of the study was to examine the effect of CXL procedure
on values of steep keratometry (K2) and central pachymetry
(CCT) six months after the intervention in keratoconusaffected
patients. Methods. Clinical prospective cohort
study included 30 eyes of 29 patients suffering from keratoconus.
All patients were examined on Allegro-Oculyzer in
order to diagnose and follow up keratoconus, thus obtaining
corneal topography parameters and parameters important
for this study: K2 and CCT, preoperatively and six
months postoperatively. The CXL procedure was carried
out by following the modified Dresden Protocol. Results.
K2 mean value was 49.01 ± 3.99 diopter (Dpt) preoperatively
and 48.06 ± 4.46 Dpt six months postoperatively. K2
decreased six months postoperatively by 0.95 Dpt, proportionally
in all patients. Student's paired sample t test showed
that average decrease of K2 (d̄ = 0.95 Dpt) was highly statistically
significant (t = 3.381; p < 0.01). CCT mean value
was 480.17 ± 36.62 μm preoperatively and 444.37 ± 45.01
μm six months postoperatively. CCT decreased six months
postoperatively by 35.8 μm, proportionally in all patients.
Student's paired sample t test showed that average decrease
of CCT (d̄ = 35.8 μm) was highly statistically important (t =
6.40; p < 0.001)). Conclusion. Application of CXL procedure
in the treatment of keratoconus with confirmed progression
highly reduces steep keratometry and central pachymetry
six months postoperatively. By steep keratometry
reducing effect the CXL procedure is efficient in the treatment
of keratoconus, especially its initial stages.

Author Biography

Mirko Resan, Military Medical Academy, Eye Clinic, Belgrade, Serbia

oftalmolog

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