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PURPOSE: To compare the clinical and tomographic properties of adult patients with keratoconus treated with accelerated corneal cross-linking (A-CXL) versus accelerated contact lens–assisted corneal cross-linking (A-CACXL). METHODS: Patients who underwent A-CXL and A-CACXL due to progressive keratoconus were enrolled from January 2015 to January 2018 in this retrospective case–control study. The treatment group (minimum corneal thickness of less than 400 µm after epithelium removal; 30 patients, 30 eyes) was treated with A-CACXL; the control group (minimum corneal thickness of 400 µm or greater, 32 patients, 32 eyes) was treated with A-CXL. Assessments occurred before treatment and 12 months postoperatively. Demographic, clinical, and tomographic data were obtained from outpatient clinic reports. RESULTS: Significant improvement in visual acuity was evident at 12-month follow-up for the control group in uncorrected distance visual acuity (0.62 ± 0.42 vs 0.43 ± 0.31 logMAR, P = .01) and the treatment group in corrected distance visual acuity (0.51 ± 0.30 vs 0.40 ± 0.49 logMAR, P = .03). Progression of keratoconus was halted at similar rates for both groups (76.7% treatment, 84.4% control, P = .21). Mean minimum corneal thickness showed minor but significant thinning at the 12-month follow-up visit compared to baseline (control group = 463 ± 31 vs 450 ± 35 µm, P > .01; treatment group = 398 ± 32 vs 388 ± 41 µm, P = .02). CONCLUSIONS: A-CACXL halted keratoconus progression in 76.7% of eyes and achieved regression in 33.3% of eyes, with rates comparable to A-CXL. Visual outcomes improved for both groups, with similar keratometry changes. A-CACXL is an effective and safe option for patients with keratoconus and thin corneas, with results similar to A-CXL treatment in patients with a minimum corneal thickness of 400 µm or greater. [ J Refract Surg . 2021;37(9):623–630.]

PURPOSE: To compare the outcomes of accelerated photoactivated chromophore for keratitis corneal cross-linking (PACK-CXL) as an adjunct treatment for bacterial keratitis (PACK-CXL plus standard antibiotic therapy) for patients receiving only standard antibiotic therapy. METHODS: Retrospective cohort study of outcomes of patients with moderate infectious presumed bacterial keratitis (ulcer diameter 2 to 7 mm and stromal depth < 300 µm) were compared before and after initiation of a new treatment protocol of PACK-CXL in addition to standard antibiotic treatment. RESULTS: A total of 70 eyes of 70 patients were included: 39 eyes in the PACK-CXL plus antibiotic (PACK-ABX) group and 31 eyes in the antibiotic only (ABX) control group. The PACK-ABX group showed shorter times to complete reepithelialization (9.3 ± 6.0 vs 16.0 ± 12.7 days, P = .01) and did not require tectonic emergency keratoplasty (0% versus 19.4%, P = .006). The PACK-ABX group also showed a higher percentage of eyes with complete reepithelialization in 6 days or less (46.2% vs 6.5%, P < .001) and a trend for shorter hospitalizations (6.3 ± 5.0 vs 8.5 ± 4.5 days, P = .06). A multivariate analysis controlling for age showed that PACK-ABX treatment remained significantly associated with early ulcer reepithelialization (odds ratio = 0.09, 95% confidence interval = 0.02 to 0.48, P = .005). CONCLUSIONS: This study validates previous findings regarding the use of accelerated PACK-CXL in the treatment of bacterial keratitis. Adding PACK-CXL improved clinical outcomes (reducing healing time) when compared to antibiotics alone. [ J Refract Surg . 2020;36(4):258–264.]

PURPOSE: To present a case of infectious keratitis in a wheel-chair user who was treated twice with high-fluence accelerated photoactivated chromophore for infectious keratitis–corneal cross-linking (PACK-CXL) at the slit lamp. METHODS: Case report. RESULTS: A 39-year-old man with progressive Duchenne muscular dystrophy presented with pain, deep corneal infection, and tearing in his left eye. Ophthalmological examination revealed a 3 × 3.5 mm corneal ulcer in the presence of a 2.5-mm hypopyon. Following a corneal scrape, antimicrobial treatment was initiated. Two consecutive adjuvant high-fluence PACK-CXL procedures (10.8 J/cm 2 each) were performed within 5 days. To avoid cardiopulmonary difficulties associated with the patient lying supine to receive PACK-CXL, the procedure was performed in the sitting (upright) position at the slit lamp. Full reepithelialization occurred 6 days after the second PACK-CXL procedure. CONCLUSIONS: In patients with reduced mobility or difficulties breathing in the supine position, CXL at the slit lamp significantly simplifies treatment. [ Journal of Refractive Surgery Case Reports. 2021;1(3):e36–e39.]

PURPOSE: To evaluate the safety and efficacy of accelerated contact lens–assisted cross-linking (A-CACXL) for patients with keratoconus and thin corneas. METHODS: This retrospective study included consecutive patients undergoing A-CACXL for progressive keratoconus from 2015 to 2017. Patients with a minimum corneal thickness of 400 µm or less after epithelium removal who underwent A-CACXL (9 mW/cm 2 for 10 minutes, using iso-osmolar 0.1% riboflavin solution and a 90-µm thick, daily disposable bandage soft contact lens) with a follow-up time of 12 months or more were included. The main outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuity and minimum corneal thickness at the last visit. Progression (increase) and flattening (decrease) were defined as a change of 1.00 diopters (D) or greater in maximum keratometry or 1.50 D or greater in mean keratometry. RESULTS: Overall, 24 eyes of 24 patients were included with a follow-up time of 18.2 ± 6.3 months and a mean minimum corneal thickness, after epithelial debridement, of 353.13 µm. There was a significant improvement in UDVA ( P = .009), maximum keratometry ( P = .03), anterior steep keratometry ( P = .04), anterior astigmatism ( P = .02), and posterior astigmatism ( P = .04) with no significant change in minimum corneal thickness ( P = .11). There was a significant improvement in UDVA (0.90 ± 0.63 to 0.64 ± 0.47 logMAR, P = .009), maximum keratometry (61.20 ± 6.30 to 59.90 ± 5.70 D, P = .03), anterior steep keratometry (55.10 ± 3.90 to 54.50 ± 4.10 D, P = .04), anterior astigmatism (5.50 ± 2.40 to 4.60 ± 2.10 D, P = .02), and posterior astigmatism (0.90 ± 0.40 to 0.80 ± 0.40 D, P = .04) with no significant change in minimum corneal thickness (from 399.8 ± 30.7 to 391.0 ± 43.8 μm, P = .11). Flattening occurred in 45.8% (n = 11) and progression in 20.8% (n = 5). There were no serious adverse events. Persistent clinically significant stromal haze occurred in one case and completely resolved by 6 months. There was no significant change in endothelial cell density ( P = .10). CONCLUSIONS: In patients with keratoconus and thin corneas, A-CACXL halted keratoconus progression in 80%, led to flattening in 45%, and significantly improved UDVA and keratometry values without any evidence of damage to the corneal endothelium or permanent adverse events. [ J Refract Surg. 2019;35(10):642–648.]

PURPOSE: To examine the rates of contamination of contact lens storage cases of refractive surgery candidates and compare the growth yields of the traditional method of culturing and a broth-based method. METHODS: Thirty contact lens storage cases of 16 asymptomatic refractive surgery candidates were studied. Samples from the lens storage case fl uid were inoculated into Bactec Peds Plus F broth (Becton Dickinson) and also directly onto blood agar, chocolate agar, and Sabouraud dextrose agar (“traditional method”). Another sample was processed for amoebal contamination. The rate of contamination of cases and the types of pathogens were evaluated for the broth-based and traditional culturing methods. Correlation between right and left storage cases of the same patient was defi ned as contamination of the two compartments with the same pathogen or pathogens. To avoid statistical bias, only one compartment was included in the study for these patients. RESULTS: Four storage cases were omitted due to growth correlation between right and left storage cases. Of the remaining 26 storage cases, 16 (61.5%) were found to be contaminated using the broth-based method and 10 (38.5%) using the traditional method (P=.011). High contamination rates were observed regardless of the type of disinfecting solution or type of contact lens used. CONCLUSIONS: The broth-based method had signifi cantly greater culture yield than the traditional method. The high rates of contamination of contact lens storage cases of refractive surgery patients may put this cohort at greater risk than non-contact lens wearing candidates for developing postoperative infections. [J Refract Surg. 2011;xx(x):xxx-xxx.] doi:10.3928/1081597X C ontact lens storage cases are a potential source and reservoir of bacteria, fungi, and amoebae. Several microbiological studies in different parts of the world have indicated consistently high rates of bacterial contamination in the contact lens cases of asymptomatic patients, ranging from 24% to 87%. 1-19 Although corneal refractive surgeries are relatively safe procedures, infection can be a rare but sight-threatening complication. The reported rates of infection after LASIK range from 0% 20 to as high as 1.2%. 21 Among the reasons leading a contact lens wearing patient to seek refractive surgery, inconvenience in wearing contact lenses was found to be either the fi rst 22 or second most important reason after the desire for improvement of unaided vision. 23 This inconvenience, to some degree, is due to the strict hygiene demands required of the patient when dealing with contact lenses and contact lens storage cases. 22 It is therefore reasonable to assume that patients’ diffi culties may have an effect on adhering to the strict hygiene rules, leading to suboptimal hygiene and possible high rates of contact lens and storage case contamination. To the best of our knowledge, no study in the literature has examined the rates of contamination of contact lens cases in refractive surgery candidates. Furthermore, all previous studies regarding contamination of contact lens storage cases examined the bacterial and fungal contamination using only the traditional method of culturing, ie, blood agar, chocolate agar, and special media for fungi such as Sabouraud agar, and not