Efficacy and Safety of Contact Lens-Assisted Corneal Crosslinking in the Treatment of Keratoconus With Thin Corneas.

OBJECTIVE: To evaluate the safety and efficacy of contact lens-assisted crosslinking (CA-CXL) in progressive keratoconus with thin corneas (350-400 µm). METHODS: Forty eyes (30 patients) underwent epithelium-off CA-CXL with iso-osmolar riboflavin and ultraviolet-A irradiation for 30 min (fluence, 3 mW/cm2). A non-ultra-violet-absorbing soft contact lens (sCL) soaked in riboflavin was applied over the cornea during irradiation. Demarcation line (DL) depth was measured 1 month postoperatively. Endothelial cell count (ECC) was measured preoperatively and 3 months postoperatively. Distance uncorrected visual acuity (UDVA) and best spectacle-corrected visual acuity (BDVA), and maximum keratometric values (K max) were evaluated preoperatively and 9 months postoperatively. RESULTS: The sCL added a mean thickness of 100.05±1.23 µm. The mean ECC was 2,982±165 cell/mm2 preoperatively and 2,955±125 cell/mm2 postoperatively (endothelial cell loss, 0.9%, P=0.21). The mean DL depth was 204.8±20.2 µm. There was significant improvement in UDVA (P<0.001) and BDVA (P=0.011) with a stable K max (P=0.06). CONCLUSION: Contact lens-assisted crosslinking was safe and effective, with endothelial loss less than 1% after 3 months and stable corneal tomography over 9 months, with improved visual acuity. Demarcation line depth was found to be shallower than conventional CXL. Therefore, the long-term efficacy of CA-CXL requires further study. CLINICAL TRIAL REGISTRY NUMBER: NCT04504578 Clinical trials.gov.

The prevalence of keratoconus in children with allergic eye disease in an Egyptian population.

PURPOSE: To determine the prevalence of keratoconus (KC) among children with ocular allergy. METHODS: A cross-sectional study was conducted on all children presenting with ocular allergic disease from September 2017 to September 2018. All study participants were subjected to history taking (a specially designed questionnaire), routine ophthalmological examination, and corneal tomography. RESULTS: A total of 79% of the study patients had vernal keratoconjunctivitis (VKC) while the remaining had perennial allergic conjunctivitis (10%), seasonal allergic conjunctivitis (9%) and atopic keratoconjunctivitis (2%). Manifest KC was seen in 7% of cases, suspect KC was found in 27% of cases, and 66% had no evidence of KC. For the manifest KC, 56% had clinical signs, while 44% were diagnosed by tomography. For the purpose of statistical analysis, the cohort was divided into group KC (manifest or suspicious KC) and group non-KC (no KC). The mean age was 11.2 years in group KC, and 9 years in group non-KC (p < 0.001). The mean duration of allergic symptoms was 3.75 years in group KC, and 2.5 years in group non-KC (p = 0.001). The mean duration of eye rubbing was 2.5 years in group KC, and 0.83 years in group non-KC (p = 0.02). Systemic atopy was present in 35.3% of group KC, and in 12.5% in group non-KC (p = 0.005). CONCLUSION: The overall prevalence of KC was 34%. Risk factors for the development of KC in patients with ocular allergy were age, duration of symptoms specially eye rubbing, systemic atopy and VKC. Tomographic diagnosis of KC can be present in absence of clinical signs.

Surgical outcome of exotropic Duane syndrome.

Purpose: To evaluate the surgical outcome of exotropic Duane syndrome and the factors that can influence the outcome.Methods: A retrospective study was performed on patients who had surgery for exotropic Duane syndrome with a minimum follow-up of 3 months. The ocular motility, the angles of deviation, the presence of abnormal head turn or overshoots, the surgical procedures performed, and their outcome were analyzed.Results: Sixty-seven patients were identified (mean age, 11.3 years). In unilateral cases with exotropia <25 PD (n = 28), ipsilateral lateral rectus (LR) recession was performed in all cases, and orthophoria was achieved in 25 patients (89.3%). In unilateral cases with angle ≥25 PD, ipsilateral LR recession was performed in 13 patients, bilateral symmetrical LR recession in eight patients, and unilateral LR recession and medial rectus (MR) resection in seven patients. Sequential contralateral LR recession for undercorrection was performed in seven patients. The success rate was highest in those who had unilateral LR recession and MR resection (66.7%). An increase in face turn occurred in 6 of 15 patients (40%) who had a simultaneous or sequential bilateral LR recession. In bilateral Duane syndrome, bilateral LR recession was performed in 10 patients, and was combined with ipsilateral MR resection in two patients with a success rate of 75%. Higher success rate was associated with young age at surgery (P = .03) and smaller angle of deviation (p = .04). The mean follow-up was 6.3 months.Conclusions: Surgical results in exotropic Duane syndrome are better in small angles of deviation and in younger age groups.