Mini-scleral contact lens for management of poor visual outcomes after intrastromal corneal ring segments implantation in keratoconus

Abstract

Purpose:To evaluate the feasibility and efficacy of mini-scleral design (MSD) contact lenses to treat keratoconus patients who were unsatisfied with the results of corneal inlay.Methods:In this prospective interventional case series, 9 eyes of 6 keratoconus patients who were unsatisfied with the results of corneal inlay were fitted with MSD contact lenses. Demographic data, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and higher order aberrations (HOAs) were evaluated before contact lens fitting. Corrected visual acuity by placing the MSD contact lens with or without over-refraction, and HOAs were measured one hour after contact lens fitting. One month after contact lens wearing, corrected visual acuity by placing the MSD contact lens with over-refraction and possible contact lens related problems were assessed. Ocular comfort and contact lens handling problems were asked in follow-up visits. The data was analyzed using descriptive statistical tests.Results:Nine eyes of 6 patients were successfully fitted with the mini-scleral lens. Fitting was ideal in 7 eyes and acceptable in 2 eyes. Mean corrected visual acuity by placing the MSD lens without over-refraction was 0.09 (range, 0.00-0.15) LogMAR which was significantly better than the mean BSCVA of 0.38 (range, 0.2-0.6) LogMAR (P = 0.007). The mean root mean square (RMS) of third-order coma and trefoil significantly decreased after MSD contact lens fitting (P = 0.012 and P = 0.015, respectively); however, changes in the fourth-order spherical aberration were not statistically significant (P = 0.336).Conclusion:Mini-scleral contact lenses may be helpful in the management of visually unsatisfied patients after corneal inlay.

Fitting Tips and Visual Rehabilitation of Irregular Cornea with a New Design of Corneoscleral Contact Lens: Objective and Subjective Evaluation

“…Precise edge lift control of such design with the lens movement and how easily fluorescein enters the lens at 6 o'clock with upward pressure ensure corneal safety, so no corneal staining was demonstrated in our fitted eyes. As regards the infection, no case of infectious keratitis was observed which agreed with previously reported results [ 13 , 15 , 33 , 37 ]. However, only one eye suffered from SPK but this was not considered to be a vision-threatening consequence.…”

“…Corneoscleral lenses with an improved peripheral fit and larger diameter allow for a better alignment of the peripheral cornea and reduced edge standoff, which discourages lens dislocation and provides the patients with adequate comfort and optimal vision [ 13 – 15 , 23 ]. As demonstrated by our experience, ScCL can delay and even prevent the need for surgery, which carries risks of infection, rejection, and postoperative severe astigmatism [ 24 – 27 ].…”

“…Scleral contact lens (ScCL) seems to be more effective in irregular corneas than traditional corneal RGP lens since it provides an effective option for correction of residual ametropia and high-order aberrations (HOAs) and masking surface corneal irregularities with the tear lens between the posterior lens surface and anterior corneal surface [ 13 – 15 ].…”

“…Most of the previous studies measured the clinical performance of the ScCL in terms of improvement in VA [ 13 , 15 – 17 ]. To the best of our knowledge, this is the first study reporting the objective and subjective results of a new design of corneoscleral contact lens namely Rose K2 XL in cases of irregular corneas with a recording of its role in correcting of mesopic vision and HOAs.…”

BCLA CLEAR – Medical use of contact lenses

“…Contact lenses are frequently required to achieve BCVA after the insertion of ICRS, especially with advanced keratoconus [199,583,584,587,[591][592][593][594]. Various lens types and designs have been described for this indication, and various contact lens modalities have been found to be well tolerated after surgery, including disposable soft lenses, toric soft lenses [595], custom-made soft lenses [583,592,593,596,597], rigid corneal lenses [584,596], piggy-back lenses [587,591,592,596,598], corneo-scleral lenses [599,600] and scleral lenses [542,594,601], which were reported to be useful after other lens types had failed [601].…”