Multiple XEN Gel Stents for Refractory Pediatric Glaucoma.

Although trabeculotomy and goniotomy are currently the mainstay of surgical management for congenital glaucoma, XEN Gel Stent (Allergan) implantation and other microinvasive glaucoma surgery technologies may offer the advantage of having a lower risk of postoperative complications than conventional techniques. A 10-year-old boy presented with aphakic glaucoma in his left eye secondary to previous cataract surgery. Intraocular pressure (IOP) in the left eye at initial presentation was 31 mm Hg with maximal tolerated medical therapy. Surgical history included tube shunt, shunt revision, and subsequent shunt removal. Shunt surgery and revision had been unsuccessful at achieving target IOP. The patient underwent two treatments of micro-pulse transscleral laser therapy that failed to achieve target IOP. At this time, an open conjunctiva ab externo superior XEN Gel Stent (Allergan) was implanted. Within 1 month of surgery, conjunctival dehiscence and contraction occurred. Following this, ab interno inferonasal air-ophthalmic viscosurgical device XEN Gel Stent implantation was performed. In the 6 months following the second XEN Gel Stent, IOP in the left eye was stable at 6 to 8 mm Hg. This report describes the effective use of a XEN Gel Stent implant in the management of congenital glaucoma, while also highlighting a complication. Further studies are required to determine the comparative outcomes of this technique with conventional surgical management. [J Pediatr Ophthalmol Strabismus. 2022;59(1):e11-e14.].

Treatment of Severe Infectious Keratitis With Scleral Contact Lenses as a Reservoir of Moxifloxacin 0.5.

PURPOSE: To report the outcomes of using scleral contact lenses as antibiotic reservoirs as a therapeutic approach in a case series of severe infectious keratitis and to discuss the clinical potential. METHODS: This was a prospective consecutive case series study of 12 eyes treated for infectious keratitis at the "Conde de Valenciana" Institute of Ophthalmology. A scleral lens (SL) filled with 0.5% moxifloxacin was used as a reservoir and replaced every 24 hours until epithelization was complete or the culture report and/or antibiogram demonstrated either a microorganism not susceptible to or resistant to moxifloxacin. RESULTS: The study included 12 eyes of 12 patients (7 women; 58.33%; average age of 63 ± 20.11 years). All patients completed at least 1 month of follow-up. Patients had a diagnosis of infectious keratitis, and the SL was fitted on initial consultation. Of the 12 eyes, 7 had culture-positive bacterial infection, 2 eyes were mycotic, and 3 eyes had no culture growth. In 3 eyes, SL was discontinued because of the lack of response (one eye) and to the presence of mycotic infection (2 eyes). All infections resolved favorably at the final follow-up. CONCLUSIONS: The use of SLs could be an alternative for antibiotic impregnation and treatment of infectious keratitis. No complications or side effects were observed related to the use of the scleral contact lens as a reservoir for the antibiotic. This treatment modality could offer a comfortable treatment for the patient, ensuring good impregnation and maintenance of antibiotic concentrations during the 24-hour wear periods.

Cool Crosslinking: Riboflavin at 4°C for Pain Management After Crosslinking for Keratoconus Patients, A Randomized Clinical Trial.

PURPOSE: To explore corneal cooling as a method of pain management in corneal-accelerated collagen cross-linking. METHODS: This was a prospective and interventional randomized clinical trial registered in the National Institutes of Health Clinical Trials through the identifier NCT030760770. The research was conducted at the Institute of Ophthalmology "Conde de Valenciana." A total of 98 patients were randomly assigned to one of the following 2 groups: cold riboflavin (4°C) group or control group (riboflavin at room temperature). The inclusion criteria were patients of any sex, older than 18 years of age with keratoconus diagnosis who needed management with cross-linking in both eyes because of the evidence of progression. The exclusion criteria were patients who had cross-linking without epithelial debridement, unilateral cross-linking, or any other ocular pathologies besides keratoconus and any cognitive incapacity that would make the understanding of the pain test difficult. The main outcome measures were pain, tearing, photophobia, foreign body sensation, and irritation. RESULTS: At 2 hours post-op, pain in the case and control groups was 3.80 ± 3.00 and 8.08 ± 2.21 (P < 0.05), tearing was 1.56 ± 1.96 and 8.29 ± 2.42 (P < 0.05), photophobia was 5.44 ± 3.57 and 7.83 ± 2.64 (P < 0.05), foreign body sensation was 2.20 ± 2.78 and 6.54 ± 2.73 (P < 0.05), and irritation was 3.48 ± 2.98 and 6.79 ± 3.00 (P < 0.05), respectively. A statistical significant difference was maintained in pain values on day 1 (2.79 ± 3.09 and 4.91 ± 3.27 [P < 0.05]), 2 (2.54 ± 2.41 and 4.00 ± 2.43 [P < 0.05]), and 4 (0.45 ± 0.76 and 1.22 ± 1.67 [P < 0.05]). CONCLUSIONS: This study demonstrated that pain and associated symptoms decreased significantly in the riboflavin 4°C group.

Pain Management in Corneal Collagen Crosslinking for Keratoconus: A Comparative Case Series.

Purpose: To compare management of postoperative pain after corneal collagen crosslinking (CXL) with oral gabapentin or ketorolac. Methods: Prospective interventional comparative case series in a single center. Patients undergoing epithelium-off (epi-off) or epithelium-on (epi-on) techniques performed by a single surgeon for progressive keratoconus were enrolled and randomly assigned to the ketorolac (10-mg tablets every 8 h) or the gabapentin (300-mg capsules every 8 h) group and instructed to take the medication for the first 3 postoperative days. Using a numeric scale of pain, scores were assessed for current pain (at the time of applying the questionnaire), and average pain over the preceding 24 h. Eye symptoms and systemic adverse events related to oral medication were also assessed. Results: Thirty-seven patients were included, with 22 (10 epi-on and 12 epi-off) assigned to the ketorolac group and 15 (7 epi-on and 8 epi-off) to the gabapentin group. No statistically significant differences were noted on the pain scale between groups at any point of the study, in the median pain scores of patients at the time of applying the questionnaire, nor in the severity of pain during the 24-h period before the assessment. Also, no differences were found among groups for the eye symptoms and the systemic adverse events. The median regression analysis showed no effect of the type of surgery or gender in the severity of pain. Conclusions: Both oral ketorolac and oral gabapentin can be used with similar results for pain and symptomatic control after epi-on or epi-off CXL procedures.

Anterior segment optical coherence tomography angle and vault analysis after toric and non-toric implantable collamer lens V4c implantation in patients with high myopia.

OBJECTIVE: To assess anterior segment changes, including iridocorneal angle and vault, after toric and non-toric implantable collamer lens (ICL) V4c (STAAR Surgical AG) implantation under different lighting conditions. METHODS: Longitudinal, prospective, case series. Patients with high myopia (>6 dioptres) underwent toric and non-toric ICL V4c implantation. Optical coherence tomography measurements were taken under different lighting conditions preoperatively and at 1 week and 1, 6 and 12 months of follow-up. RESULTS: Seventy-six eyes of 42 patients underwent ICL V4c implantation. Mean age was 27.4 years (±5.14 years, range 20 to 39 years). The average iridocorneal angle showed a statistically significant decrease (p<0.05) in all mesopic, scotopic and photopic conditions after 1 week of surgery compared with the preoperative measurements; in mesopic conditions, it decreased 14.1°, in photopic conditions 14.8° and scotopic conditions 13.2°. The angle measurement had a statistically significant change only in mesopic conditions (p=0.01) over the 1-year follow-up. The average vault under mesopic conditions was 0.661±0.21 mm at week 1. The vault measurement change was statistically significant over the 1-year follow-up in mesopic conditions (p=0.01). Refractive results showed a significant improvement in both uncorrected and corrected distance visual acuity (p<0.001). CONCLUSION: There is a significant reduction in the iridocorneal angle after ICL V4c implantation. Furthermore, there is a change under mesopic conditions in both the iridocorneal angle and vault during long-term follow-up.

Trans-epithelial accelerated corneal cross-linking for keratoconus in children.

The aim of the study is to evaluate the safety and efficacy of trans-epithelial accelerated corneal cross-linking (TE-ACXL) in children with progressive keratoconus. Retrospective, case-series of 23 eyes of 14 children who underwent TE-ACXL. Evaluations were performed at baseline and 1, 3, 6, 12 and 18mo postoperatively. Mean follow-up time of 23.82±3.15mo and mean age was 13.7±1.4y (range 11 to 16y). Mean preoperative uncorrected distance visual acuity changed from 0.92±0.45 logMAR (20/160) to 0.71±0.40 logMAR (20/100) (P=0.001). Mean keratometry (Km) changed from 53.87± 6.03 to 53.00±5.81 (P=0.001). Pachymetry did not have significant changes at last follow-up (P=0.30). The mean preoperative sphere was -5.58±2.48 and -4.89±4.66 D (P=0.11) at last follow-up; refractive cylinder from -5.58±2.48 to -5.02±2.23 (P=0.046). In conclusion, tomographic and refractive stability are shown in over 91% of eyes with pediatric progressive keratoconus who underwent TE-ACXL.

Bacterial Keratitis in Toronto: A 16-Year Review of the Microorganisms Isolated and the Resistance Patterns Observed.

PURPOSE: To review the incidence, distribution, current trends, and resistance patterns of bacterial keratitis isolates in Toronto over the past 16 years. METHODS: Microbiology records of suspected bacterial keratitis that underwent a diagnostic corneal scraping and cultures from January 1, 2000, through December 31, 2015, were retrospectively reviewed. The distribution of the main isolated pathogens and in vitro laboratory minimum inhibitory concentration testing results were used to identify resistance patterns. RESULTS: A total of 2330 corneal scrapings were taken over 16 years. A pathogen was recovered in 1335 samples (57.3%), with bacterial keratitis accounting for 1189 of the positive cultures (86.0% of all isolates). The total number of gram-positive and gram-negative isolates was 963 and 324, respectively. Coagulase-negative Staphylococcus and Pseudomonas aeruginosa were the most common gram-positive and gram-negative bacteria isolates, respectively. A decreasing trend in the number of isolates in gram-positive bacteria (P = 0.01), specifically among Staphylococcus aureus (P < 0.0001) and Streptococcus species (P = 0.005), was identified. When analyzing the susceptibilities of gram-positive and gram-negative isolates, an increasing trend in antibiotic resistance was observed in erythromycin (P = 0.018), ceftazidime (P = 0.046), and piperacillin/tazobactam (P = 0.005). The susceptibility of tested gram-positive microorganisms to vancomycin was 99.6%. CONCLUSIONS: There has been a decreasing trend in the number of isolates in gram-positive microorganisms over the past 16 years. An increasing trend in resistance for various antibiotics against gram-negative and gram-positive isolates was identified. High susceptibility to vancomycin reinforced the empirical use of fortified tobramycin and vancomycin in the initial management of severe bacterial keratitis.

Long-term Outcomes of Pediatric Penetrating Keratoplasty for Herpes Simplex Virus Keratitis.

PURPOSE: To analyze the characteristics and long-term outcomes of patients that underwent pediatric penetrating keratoplasty (PPK) for herpes simplex virus (HSV) keratitis. DESIGN: Retrospective, interventional, consecutive case series. METHODS: Observational report of outcomes and findings for 9 patients with history of HSV keratitis that underwent PPK and were followed in a single institution. Difference between the median preoperative and final best-corrected visual acuity (BCVA) was assessed and the outcomes are reported. RESULTS: We included 9 eyes; median age at the moment of the PPK was 14 years. The median initial BCVA was 20/400 (range 20/60 to hand motion) and final was 20/50 (range 20/30 to 20/400) (P < .05). Follow-up was a median of 94 months. Complications in these patients included glaucoma (1), graft rejection (1), recurrence of disease (1), and amblyopia (3). No graft failures were present. CONCLUSION: The long-term outcomes with PPK for HSV keratitis in children provide improvement in BCVA when not compromised by amblyopia.

Outcomes of photorefractive keratectomy following laser in situ keratomileusis: a cohort study.

OBJECTIVE: To analyze the outcomes of photorefractive keratectomy (PRK) on residual myopia and hyperopia post-laser in situ keratomileusis (LASIK) and to compare these results with PRK on eyes without previous laser refractive surgery. DESIGN: Retrospective comparative cohort study. PARTICIPANTS: Patients undergoing PRK between 2006 and 2010 were reviewed. METHODS: Patients were divided into 4 groups, myopic or hyperopic PRK post-LASIK (mPRK-PL and hPRK-PL, respectively) and myopic or hyperopic PRK on corneas without previous laser refractive surgery (mPRK and hPRK, respectively). Uncorrected and corrected distance visual acuity, mean refractive spherical equivalent (MRSE), and mean keratometry and aberrations (total, higher order [HOA], coma, trefoil, and spherical aberration) were recorded at months 3 and 6 postoperatively, as were complications and attempted versus achieved MRSE. RESULTS: Thirty-three eyes of 25 patients who underwent PRK post-LASIK (21 eyes of 14 patients for hPRK-PL and 12 eyes of 11 patients for mPRK-PL) and 35 eyes of 21 patients who underwent PRK on virgin eyes (11 eyes of 8 patients for hPRK and 24 eyes of 13 patients for mPRK) were included in the study. The only significant differences in outcomes were found to be HOA at 3 months for hPRK-PL as compared with both hPRK and mPRK. Achieved MRSE was significantly different from expected MRSE for hPRK-PL at 3 months postoperatively. No haze- or flap-related complications were observed. CONCLUSION: Outcomes of PRK were not different in myopic and hyperopic corrections post-LASIK by 6 months or when compared with PRK in virgin eyes. HOA may render hPRK-PL results less predictable early in the postoperative period.

Scheimpflug and Optical Coherence Tomography Analysis of Posterior Keratoconus.

PURPOSE: To report a case series of 7 eyes of 6 patients with posterior keratoconus, evaluating corneal Scheimpflug tomographic changes and anterior-segment optical coherence tomography (OCT). METHODS: In our descriptive study, 6 patients were diagnosed with posterior keratoconus: 5 unilateral (7-, 33-, and 42-year-old males and 64- and 60-year-old female) and 1 bilateral (45-year-old female). Patients were diagnosed with slit-lamp examination, which revealed corneal opacity with an underlying posterior corneal depression. Additional analysis with anterior-segment OCT and Scheimpflug tomography evaluation was performed. RESULTS: Localized paracentral posterior keratoconus was diagnosed in 7 eyes. Scheimpflug images demonstrated posterior corneal depression. Clinical findings were examined by OCT. Genetic analysis revealed no alterations or associated syndromes. All patients were amblyopic in the affected eye, and no surgery was offered to improve their visual acuity. CONCLUSIONS: Posterior keratoconus is a rare noninflammatory condition usually present at birth and sometimes related to developmental abnormalities. Posterior keratoconus is usually unilateral and can present as a generalized or localized change in posterior corneal curvature.

Combined small-incision lenticule extraction and intrastromal corneal collagen crosslinking to treat mild keratoconus: Long-term follow-up.

PURPOSE: To report visual, refractive, and topographic outcomes of sequential, same-day small-incision lenticule extraction and intrastromal corneal collagen crosslinking (CXL) in eyes with mild keratoconus. SETTING: Institute of Ophthalmology Conde de Valenciana, Mexico City, Mexico. DESIGN: Prospective interventional case series. METHODS: Fifteen eyes with forme fruste keratoconus and/or irregular corneas, corrected distance visual acuity 20/40 or better, stable refraction of at least 1 year, age 18 years or older, and residual corneal thickness of greater tan 400 µm before performing collagen crosslinking were studied. Patients were treated with small-incision lenticule extraction followed by intrastromal injection of riboflavin inside the pocket. Ultraviolet A light with a wavelength of 370 nm to 3 mW/cm(2) was applied for 30 minutes. Follow-up was done at 1 day, at 1 week, and at 1, 3, 6, 12, 18, and 24 months. RESULTS: Eight patients were included in the study. The mean age was 29.5 years ± 5.5 (SD) (range 20 to 36 years). Twenty-four months of follow-up were completed in 13 eyes, and 12 months were completed in 2 eyes. Preoperative uncorrected distance visual acuity improved from 1.6 ± 0.3 LogMAR (Snellen 20/796) to postoperative 0.12 ± 0.20 LogMAR (Snellen 20/26) and was statistically significant (P < .001). Best-corrected distance visual acuity did not change significantly (P = .186), from 0.006 ± 0.02 LogMAR (Snellen 20/20) preoperatively to 0.04 ± 0.05 LogMAR (Snellen 20/21) postoperatively, and spherical equivalent improved from -4.3 ± 1.02 preoperatively to 0.2 ± 0.66 (P < .001). CONCLUSION: Although further follow-up and larger samples are needed to fully confirm these findings, the results suggest that combined small-incision lenticule extraction and intrastromal corneal collagen crosslinking are a promising treatment option for patients for whom conventional laser refractive surgery is contraindicated. FINANCIAL DISCLOSURE: Drs. Ramirez-Miranda and Navas are consultants to Carl Zeiss Meditec. No other author has a financial or proprietary interest in any material or method mentioned.

Minor ipsilateral simple limbal epithelial transplantation (mini-SLET) for pterygium treatment.

We describe a novel surgical technique for pterygium removal taking advantage of the properties of amniotic membrane and limbal epithelial stem cells. A total of 10 eyes underwent pterygium excision with amniotic membrane coverage of the bare sclera and placement of pieces of limbal epithelium in a linear fashion in the affected limbal area covered by a second amniotic membrane using fibrin glue. After up to 8 months of follow-up, there were no signs of early recurrence or sight-threatening complications. The minor ipsilateral simple limbal epithelial transplantation technique for the treatment of pterygium requires less tissue than the conventional conjunctival autograft, leaving healthy conjunctiva if needed for another procedure in the future and offers the advantages of epithelial stem cells, which in the long term may reduce the rate of recurrence significantly.

Accelerated versus standard corneal collagen crosslinking combined with same day phototherapeutic keratectomy and single intrastromal ring segment implantation for keratoconus.

AIM: To compare the results of same day transepithelial phototherapeutic keratectomy (t-PTK) and single inferior intracorneal ring segment (ICRS) combined with standard versus accelerated corneal collagen crosslinking (CXL) for keratoconus. METHODS: All consecutive progressive keratoconus eyes that underwent standard or accelerated CXL treatment preceded by same day t-PTK and placement of a single inferior ICRS and had 6  and 12 months of follow-up were reviewed retrospectively. Eyes were classified into two groups, the 'standard' and the 'accelerated' group, accordingly. Visual, refractive and topographic data prior to surgery and at 6 and 12 months post-treatment were analysed. RESULTS: Sixteen eyes were included in each of the standard and the accelerated groups. Mean patient age was 27.5±8.5 years and 30.5±10.7 years (p=0.38) in the standard and accelerated groups, respectively. There was a significant improvement in uncorrected distance visual acuity, refractive cylinder and all examined corneal parameters in both groups 12 months postsurgery. The corrected distance visual acuity and manifest refraction spherical equivalent showed a significant improvement after 12 months of follow-up only in the accelerated group. However, mean changes in all evaluated parameters did not differ significantly between the two groups. CONCLUSIONS: A combined treatment of accelerated CXL preceded by same day t-PTK and single ICRS is as effective as the combined treatment using standard CXL for visual rehabilitation in progressive keratoconus.

Accelerated (9-mW/cm2) corneal collagen crosslinking for keratoconus-A 1-year follow-up.

PURPOSE: The aim of this study was to assess the efficacy of accelerated crosslinking (irradiance of 9 mW/cm; 10 minutes) in keratoconus-affected eyes through topographical, visual, and refractive end points. METHODS: Mild-moderate keratoconus-affected eyes that underwent accelerated corneal collagen crosslinking (CXL) treatment and had 6 and 12 months of follow-up were reviewed retrospectively. Data regarding uncorrected distance visual acuity (UDVA), manifest refraction, corrected distance visual acuity (CDVA), and computerized corneal topography data before surgery and post-CXL treatment were extracted and analyzed. RESULTS: Sixteen eyes of 14 patients were included in the study. The mean patient age was 24.9 ± 5.8 years (range: 17.1-38.3 years). No statistically significant changes were found in the mean CDVA, mean refractive cylinder, or mean manifest refraction spherical equivalent at either time point. There was a gain of 0.13 logarithm of the minimum angle of resolution lines in the mean UDVA (P = 0.012) at 12 months. All corneal parameters including Ksteep, Kflat, average K (Km), corneal astigmatism (Kcyl), and maximal curvature reading at the corneal apex (Kmax) were stable at 6 and 12 months in all patients. No complications were observed during the follow-up period. CONCLUSIONS: Accelerated corneal CXL is effective in stabilizing topographic parameters after 12 months of follow-up in mild-moderate keratoconus-affected corneas. Improvement in the UDVA and stabilization of all tested corneal parameters were noted after the treatment. However, a longer follow-up with larger cohorts is necessary to validate these findings.

EndoGlide versus EndoSerter for the insertion of donor graft in descemet stripping automated endothelial keratoplasty.

PURPOSE: To compare 2 lenticule insertion methods currently in use for Descemet stripping automated endothelial keratoplasty (DSAEK). DESIGN: Prospective randomized single-masked study. PATIENTS AND METHODS: Twenty patients with Fuchs endothelial dystrophy and pseudophakic bullous keratopathy undergoing DSAEK surgery were included and randomized to the use of either EndoGlide or EndoSerter as a delivery method for the donor lenticule. Post surgery, patients were monitored for up to 1 year. Evaluation included corrected distance visual acuity (CDVA) and refraction. Specular microscopy images were obtained at the 6- and 12-month visits. Complications, including rebubbling rate, graft dislocation, and graft failure, were recorded. RESULTS: Twenty eyes were randomized to receive the Tan EndoGlide or the EndoSerter injector for lenticule insertion. Mean patient age was 65.9±8.4 years and 70.3±9.8 years in the Tan EndoGlide and EndoSerter groups, respectively (P=.3). Two eyes in each group needed rebubbling. The mean endothelial cell loss, including the rebubbled eyes, at the 12-month visit was 1093±629 cells/mm2 (range: 239-2109 cells/mm2, mean percentage cell loss 41.2%) and 877±566 cells/mm2 (range: 116-1851 cells/mm2, mean percentage cell loss 31.4%) in the Tan EndoGlide and EndoSerter groups, respectively (P=.45). Mean CDVA did not show a statistically significant difference between the 2 groups at the 6- or 12-month visit. CONCLUSION: The EndoSerter shows comparable results to the Tan EndoGlide. However, further investigation is warranted in order to validate these findings.

Collagen crosslinking after radial keratotomy.

PURPOSE: The aim of this study was to report the outcomes of corneal collagen crosslinking (CXL) after previous radial keratotomy (RK) in patients with decreasing visual acuity and/or diurnal visual fluctuations. METHODS: The charts of all patients who had undergone CXL because of a worsening corrected distance visual acuity (CDVA) and/or diurnal visual fluctuations after RK were reviewed retrospectively. Uncorrected distance visual acuity, CDVA, manifest refraction, and corneal topography were recorded preoperatively and at 1, 3, 6, and 12 months after the procedure. RESULTS: Nine eyes of 6 patients that had undergone an RK 15 to 23 years before the CXL were included in the study. In 5 patients (8 out of 9 eyes), discontinuation of diurnal visual fluctuation was reported between 6 and 12 months after the CXL. The mean uncorrected distance visual acuities pre and 12 months after the CXL were 0.7 logarithm of the minimum angle of resolution (logMAR) and 0.6 logMAR, respectively (P = 0.3). The mean CDVAs pre and 12 months after the CXL were 0.2 logMAR and 0.1 logMAR (P = 0.5), respectively. The mean average keratometry pre and 12 months after the CXL were 40.1 and 39.1 diopters (P = 0.06), respectively. The mean corneal astigmatism values pre and 12 months after the CXL were 2.3 and 1.9 diopters (P = 0.06), respectively. The mean manifest refraction spherical equivalents (MRSEs) before and 12 months after the CXL were +1.4 and +2.5 (P = 0.1), respectively. CONCLUSIONS: CXL is a safe and effective method to restore corneal stability in eyes with a history of RK. However, some of the effect that was achieved at the 6-month visit was blunted at the 12-month visit. Therefore, a longer follow-up is necessary to validate these findings.