Purpose
To evaluate outcomes at 4 and 5 years after cross-linking (CXL) for progressive keratoconus (KC) performed in children up to 18 years of age.
Methods
Retrospective evaluation of CXL in children with 4- and 5-year follow-up periods. Of 50 eyes treated with the standard Dresden protocol, 19 (15 patients) met the inclusion criteria. Pre- and postoperative exams included topography and tomography. Mean age was 14.6±2.9 years (range 8-18 years).<br />
Results
There was one case of progression 3 years after CXL in a 13 year old girl (KMax increased from 64.4 to 71.3D). Of the remaining 18 eyes, 16 had 4-year data and 11 5-year data. CDVA remained unchanged or improved in every eye. Average Ks flattened (47.7±3.2D preoperatively, 46.9±3.0D at 4 year; 48.6±2.8 pre-CXL and 47.9±2.4 at 5 years). The cylinder did not change. The spherical equivalent changed significantly (preoperatively -3.5±4 and -4.2±3.9, at 4 years; -2.0±-3.9 pre-CXL and -2.6±3.2 at 5 years). Mean Kmax decreased from 53.7±5.9D and 56.5±5.7D preoperatively to 51.4±5.7D and 54.9±3.9D at 4 and 5 years, respectively. These changes were all borderline statistically significant (p=0.05). Topographic indices (SAI and SRI) showed minimal improvement. Pachymetry at the thinnest point decreased significantly (493±36 µm and 488±45 preoperatively, to 451±38D µm and 440±38µm at 4 and 5 years).
Conclusions
CXL is very effective in arresting KC progression in children. However, longer term follow-up is needed , since progression may develop years after surgery.