Two-stage treatment of ametropia in patients with keratoconus and cataracts

Keratoconus (KC) is a progressive degenerative corneal disease, leads to the aberration of biomechanical and optical properties and thinning of the cornea, causes astigmatism and decreases visual acuity.Materials and methods. 33 patients (35 eyes) with stages II–III of non-progressive keratoconus and concomitant cataracts of various stages of maturity were operated on. The average age of the patients was 46.5 ± 2.7 (41–63) years old. The operations were performed according to our proposed two-stage method of treating ametropia in patients with KC and cataracts (Patent of the Russian Federation No. 2748634 of 28.05.2021). The first stage was the implantation of FERRARA intrastromal corneal ring segments (ICRS) with thickness from 150 to 350 μm. To correct residual refractive error in 5–7 months after stage 1, patients underwent stage 2: cloudy lens was removed and replaced with toric posterior chamber intraocular lens (TIOL) – AcrySof IQ Toric (Alcon, USA), T-fl ex Toric RayOne (Rayner, UK).Results and discussion. After stage 1 of the operation (ICRS implantation), the uncorrected visual acuity (NCVA) was 0.2 ± 0.03, the best corrected visual acuity (BCVA) was 0.4 ± 0.02. In 1 month after stage 2 (phacoemulsifi cation + TIOL) NCVA was 0.64 ± 0.11 and BCVA was 0.74 ± 0.12. During the entire follow-up period after the surgery visual functions, refraction, and rotational stability of TIOL were stable.Conclusions. Conducting a two-stage surgical intervention in patients with keratoconus and cataracts allows to stop the progression of the disease and effectively correct the ametropia concomitant with keratoconus.

Ferrara Rings for Visual Rehabilitation in Eyes with Keratoconus and Previous Cross-Linking Using the Ferrara Ring Nomogram

Purpose: To report the visual, refractive and tomographic outcomes following the implantation of intrastromal corneal ring segments (ICRS) (Ferrara rings, AJL Ophthalmics, Miñano, Spain) in eyes with a history of keratoconus and corneal cross-linking using the Ferrara ring nomogram. Methods: Retrospective, interventional case series performed at the Corneoplastics Unit, Queen Victoria Hospital, East Grinstead, United Kingdom. Results: 21 eyes of 19 patients with a history of keratoconus and prior corneal collagen cross-linking had Ferrara Intrastromal Corneal Ring Segments implanted between December 2015 and October 2017. The number, thickness and length of ring segments was chosen based on the Ferrara ring company nomogram. Mean uncorrected visual acuity (UDVA) improved from 0.88 to 0.52 logMAR (p < 0.001). Mean corrected visual acuity (CDVA) improved from 0.47 to 0.36 logMAR (p = 0.046). The percentage of eyes achieving 20/40 UDVA and CDVA increased from 5% to 38% and from 38% to 67%, respectively. Of the eyes, 52.3% gained at least two lines of CDVA. The spherical equivalent improved from −7.51D to −3.76D (p < 0.001) and the refractive astigmatism magnitude improved from 5.14D to 2.76D (p = 0.004). There were significant improvements in the corneal tomography with mean keratometry (KM) improving from 50.40D (3.53) to 48.24D (3.00) (p = 0.01) and keratometric astigmatism magnitude improving from 5.14D (2.91) to 2.76D (1.67) (p = 0.004). Conclusion: Insertion of Ferrara rings in keratoconic eyes with a history of prior cross-linking using the company nomogram results in significant improvements in visual, refractive and tomographic outcomes.

Assesment of the quality of information patients on treatment of keratoconus on YouTube

Purpose To evaluate the reliability, quality and effectiveness of YouTube videos adressing treatment of keratoconus. Methods This is a retrospective, cross-sectional and register-based study. A YouTube search was performed using the keyword treatment of keratoconus and the first 100 videos that came out were included in the study. The numbers of views, likes, dislikes, comments, daily viewing rate (number of views per day), uploaded source (physicians, public or private institution, health channel or patients), country of origin, video type (patient experience, scholarly information), and describe treatment technique (contact lens, corneal crosslinking, intrastromal corneal ring, topography guided-photorefractive keratectomy, keratoplasty) were evaluated for all videos. They were also evaluated regarding their DISCERN, Journal of the American Medical Association (JAMA), global quality (GQS) and usefulness scores by two independent ophthalmologists. Results Of the top 100 videos, 83 videos met the criteria. The mean DISCERN, JAMA, GQS and usefulness score were 42.92 ± 18.14, 2.7 ± 0.73,3.07 ± 1.25 and 2.99 ± 1.44, respectively. Of the 83 videos, 35(42.2%) had been uploaded by physicians, 19(22.9%) by patients, 15(18.1%) by health channel and 14(16.9%) by institutions/private health institutions. In the correlation analysis, the four scoring systems showed a statistically significant and strong positive correlation with each other (p < 0.001). In addition, viewing rate DISCERN, GQS, usefulness scores, number of likes, dislikes and comments showed a statistically significant positive correlation. Conclusion The content of YouTube videos regarding treatment of keratoconus is of generally good quality and is educational for patients. Increasing the number of videos uploaded by healthcare professionals will increase the quality, reliability and informative features of the videos.

Delayed Perforation of an Intrastromal Corneal Ring Segment into the Anterior Chamber: A Case Report and Review of the Literature

Intrastromal corneal ring segments (ICRSs) are an effective treatment for stabilizing and normalizing corneal shape in patients with keratoconus and other corneal ectasias. Intraoperative segment perforation through the corneal endothelium into the anterior chamber (AC) is an uncommon but known complication. However, perforation into the AC postoperatively is an exceedingly rare complication with only 3 reported cases in the literature. One case was due to Descemet membrane detachment and another due to ocular trauma. In the third case, the mechanism for perforation was unclear. We present the fourth case of delayed ICRS perforation due to silent migration through the endothelium into the AC. We also present all reported cases in the literature of intraoperative and postoperative perforation into the AC.

Comparison between different tonometers following intrastromal corneal ring segments implantation

Purpose: To compare different intraocular pressure (IOP) readings in corneas with intrastromal corneal ring segments (ICRS) taken by three different tonometers; Goldmann applanation tonometry (GAT), air puff tonometer, and ocular response analyzer (ORA) corneal-compensated IOP (ORA-IOPcc) and determine the relation of these measurements to different corneal parameters taken by Pentacam. Methods: An observational cross-sectional analytic study included patients who underwent ICRS keraring implantation at 3 months. In each eye, the two rings were placed using the femtosecond laser assisted technique 5.5 or 6 mm from the center. IOP was measured using three different tonometers; GAT, air puff tonometer, and ocular response analyzer (ORA) corneal-compensated IOP (ORA-IOPcc). Results: Fifty eyes of 30 patients (20 males and 10 females) aged 27.56 ± 6.38 years were included. IOP measurements by GAT, air puff tonometer, and ORA-IOPcc were 13.28 ± 2.13 mmHg, 10.47 ± 2.55 mmHg, and 13.19 ± 2.78 mmHg, respectively. Comparisons between air puff and each of GAT and ORA-IOPcc were statistically highly significant ( p-value <0.001). Conclusion: IOP measurements taken by air puff tonometer were significantly lower than those taken by GAT and ORA-IOPcc. These differences were not constant across the pressure range but increased as the pressure values determined using GAT and ORA increased. ORA-IOPcc and GAT showed similar readings. No correlation was found between any of the IOP readings taken by the three tonometers and the central corneal thickness.

Outcomes of a Single-Segment Intrastromal Corneal Ring in Early Keratoconus Versus Early Pellucid Marginal Degeneration

Purpose: To determine the effect of a single-segment intrastromal corneal ring segment (ICRS;Intacs-SK) on early keratoconus (KCN) or pellucid marginal degeneration (PMD).Methods: It is a prospective interventional study. One-hundred-twenty-four eyes (99 patients) with KCN and 36 eyes (26 patients) with PMD at early stage (the maximum keratometric reading less than 55 diopters) were included to ICRS implantation using femtosecond laser at a tertiary university-based hospital and a private outpatient center. The uncorrected distance and spectacle-corrected visual acuity (UDVA and SCDVA), manifest spherical and cylindrical refractions, and keratometry indices were measured preoperatively and postoperatively, 1 week, 2 and 6 months.Results: One week after surgery, significant improvements were observed in UDVA, SCDVA, cylinder and keratometry readings of both KCN and PMD groups (all P<0.05) with no significant changes afterwards. No significant change occurred in the sphere refraction of PMD group (P=0.10) in contrast to KCN group (P<0.001). Corneal irregularity of KCN group in central 3 and 5 mm zones increased at 1 week (both P<0.001) and then continued to decrease up to 6 months. However, the corneal irregularity of PMD group had significant reduction only at 1 week in 5-mm zone (P=0.02) and 2 months in 3-mm zone (P=0.01) postoperatively. The final efficacy indexes were 1.44±0.71 and 0.87±0.40 in KCN and PMD groups, respectively. Conclusion: Visual acuity and keratometry values reached stability at 1 week, after one-segment Intacs-SK implantation in KCN and PMD groups. The short-term efficacy of the procedure was more in early KCN compared to early PMD.