JCRS HIGHLIGHTS

Crosslinking and straylight

Despite promising clinical results, corneal crosslinking (CXL) frequently causes a reduction in visual acuity during the initial postoperative phase. Looking into potential factors for this, a retrospective cohort study evaluated the change in backward-directed and forward-directed corneal straylight in eyes after CXL and its correlation with corrected distance visual acuity (CDVA) and changes in corneal topography. Crosslinking-induced stromal changes resulted in an increase in densitometry, especially in the anterior stroma of the central (0.0 to 2.0mm) zone. These changes correlated with an increase in retinal straylight but not with the postoperative CDVA values. Although post-CXL corneal transparency remained altered for at least 12 months, this transparency change did not seem to affect high-contrast visual acuity. No correlation was found between corneal straylight and retinal straylight and CDVA. This study also provides evidence that a more pronounced transparency loss in the central anterior layer seems to be associated with a more pronounced reduction in maximum K readings.
N Pircher, JCRS, “Changes in straylight and densitometry values after corneal collagen crosslinking”, In Press, May 2015.

Stromal lenticules for keratoconus

Tailored stromal expansion for performing CXL in thin and ultrathin corneas, by adding a myopic lenticule to the ectatic corneal surface following epithelial debridement, represents a potential new approach to treating keratoconus. The stromal lenticule is placed and spread over the host cornea following epithelial debridement so the thickest area of the 6.2mm diameter lenticule corresponds to the thinnest area of the cone. The remaining collagen crosslinking procedure is carried out in a routine manner. Early results indicate the approach is safe and effective. M Sachdev et al, JCRS, “Tailored stromal expansion with a refractive lenticule for crosslinking the ultrathin cornea”, In Press, May 2015.

Corneal ectasia and SMILE

Corneal ectasia has not been reported after small-incision lenticule extraction (SMILE)- until now. Researchers describe a case of a 19-year-old patient with forme fruste keratoconus who developed ectasia six months after SMILE. Ectasia was diagnosed based on anterior and posterior surface keratometry of 38.4/39.5 dioptres (D) and −6.3/−6.8D, respectively, in the right eye and 38.6/40.8D and −7.1/−6.6D, respectively, in the left eye. The keratometry increased gradually and the corneal thickness decreased after surgery, and these trends continued during the 13-month follow-up. This finding suggests a need to apply the same regulations used for LASIK to SMILE. This includes stricter regulation of patient recruitment before the procedure and postoperative follow-up.
Y Wang et al, JCRS, “Corneal ectasia 6.5 months after small-incision lenticule extraction”, In Press, May 2015.