Impact of removing soft contact lenses 1 day versus 1 month before surgery on the outcomes of microkeratome laser in situ keratomileusis.

PURPOSE: To compare the outcomes, safety, efficacy, and predictability of microkeratome laser in situ keratomileusis (LASIK) 24 h and one month or more after removing soft contact lenses. SETTING: ULTRALASIK Eye Center, Dubai, United Arab Emirates. METHODS: The patients were divided based on the time of discontinuation of the soft contact lenses before LASIK (Group 1 at 24 h and Group 2 at one month or longer), and the two groups were well matched. Schirmer's testing, tear break-up time, corrected distance visual acuity, uncorrected distance visual acuity, manifest refraction spherical equivalent, and infection rate were evaluated preoperatively and at one week, one month, and six months after treatment. RESULTS: Group 1 (G1) comprised 1025 eyes, and group 2 (G2) had 1052 eyes. The groups were comparable preoperatively. The overall-mentioned outcomes were comparable between groups with uncorrected distance visual acuity of - 0.084 ± 0.12 logMAR in G1 and - 0.078 ± 0.17 logMAR in the G2 at 6 months (P = 0.322). Tear break-up time as well as Schirmer's testing results was also comparable with no evidence of increased risk of dry eyes or non-inflammatory complications in any of the groups on follow-up visits at 1 week (P = 0.421), 1 month (P = 0.101), and 6 months (P = 0.399) postoperatively. Finally, no infectious complications were recorded in either of the groups. CONCLUSION: With the absence of corneal warpage, no statistical or clinical difference in microkeratome LASIK outcomes and safety was spotted between the groups despite the difference in SCL discontinuation time before the procedure.

Femtosecond-assisted LASIK flaps resistant to lift secondary to corneal epithelial defects: Case reports and ex vivo studies.

PURPOSE: To evaluate why epithelial defects created before femtosecond laser ablation result in laser in situ keratomileusis (LASIK) flaps resistant to lift. SETTING: Boston Eye Group, Brookline, Massachusetts, USA. DESIGN: Case reports and ex vivo studies. METHODS: To examine the mechanism of resistance to flap lift after epithelial defects, flap creation with a femtosecond laser was performed in 30 fresh porcine eyes. Before ablation, the eyes were assigned to 3 groups. Group 1 was a control group with intact corneal epithelium. In Group 2, a central 2.0 mm corneal epithelial defect was created by marking it with a 2.0 mm trephine. In Group 3, a peripheral 2.0 mm epithelial defect was created similarly. After the femtosecond laser procedure was performed, the flaps were lifted and the resistance to lift was documented. The corneas were further examined using anterior segment optical coherence tomography. RESULTS: In Group 1, no resistance was felt during flap lifts. In Group 2, significant resistance was encountered at the edge of the epithelial defects and the flaps could not be lifted in 7 of 10 eyes. In Group 3, similar significant resistance was encountered in all 10 eyes. Six of 10 flaps could not be lifted. Anterior segment optical coherence tomography from a representative cornea from Group 2 demonstrated a deeper dissection plane in the area where the overlying epithelium was missing. CONCLUSION: Epithelial defects can interfere with proper LASIK flap creation with the femtosecond laser. This seems to be attributable to a deeper cutting plane under the area of the epithelial defects compared with the surrounding area with intact epithelium.

Surgical adhesives in ophthalmology: history and current trends.

Tissue adhesives are gaining popularity in ophthalmology, as they could potentially reduce the complications associated with current surgical methods. An ideal tissue adhesive should have superior tensile strength, be non-toxic and anti-inflammatory, improve efficiency and be cost-effective. Both synthetic and biological glues are available. The primary synthetic glues include cyanoacrylate and the recently introduced polyethylene glycol (PEG) derivatives, while most biological glues are composed of fibrin. Cyanoacrylate has a high tensile strength, but rapidly polymerises upon contact with any fluid and has been associated with histotoxicity. Fibrin induces less toxic and inflammatory reactions, and its polymerisation time can be controlled. Tensile strength studies have shown that fibrin is not as strong as cyanoacrylate. While more research is needed, PEG variants currently appear to have the most promise. These glues are non-toxic, strong and time-effective. Through MEDLINE and internet searches, this paper presents a systematic review of the current applications of surgical adhesives to corneal, glaucoma, retinal, cataract and strabismus surgeries. Our review suggests that surgical adhesives have promise to reduce problems in current ophthalmic surgical procedures.

EFFICACY OF INTRAVITREAL RANIBIZUMAB INJECTIONS IN THE TREATMENT OF VITREOUS HEMORRHAGE RELATED TO PROLIFERATIVE DIABETIC RETINOPATHY.

PURPOSE: To investigate the efficacy of intravitreal ranibizumab injections in proliferative diabetic retinopathy associated with vitreous hemorrhage (VH). METHODS: A prospective study including patients with proliferative diabetic retinopathy who presented with persistent VH. Vitreous hemorrhage was graded into mild, moderate, and severe. Patients were randomized into two groups: the ranibizumab group was treated with intravitreal injections of ranibizumab and the control group was assigned to observation alone. Vitrectomy was performed if there was any aggravation of the VH in patients with mild, moderate, and severe VH or in the absence of improvement by 16 weeks in patients with moderate and severe VH. RESULTS: The ranibizumab group included 71 patients and the control group included 62 patients. There was a statistically significant difference in the vitrectomy rate in patients with mild-to-moderate VH (5 patients [7.04%] and 12 patients [19.35%], respectively; P = 0.04). However, there was no statistically significant difference in the overall vitrectomy rate, and in the vitrectomy rate in severe VH (17 [23.94%] and 12 [16.90%] patients in the ranibizumab group vs. 22 [35.48%] and 10 [16.13%] patients in the control group, P = 0.14 and P = 0.83, respectively). Recurrence of the VH occurred in 22 patients in the ranibizumab group and 29 patients in the control group (P = 0.06). Better visual acuity measurements were recorded on all follow-up visits in the ranibizumab group (P ≤ 0.04). CONCLUSION: Intravitreal ranibizumab injections could be considered in proliferative diabetic retinopathy patients with mild and moderate VH.

Accuracy of Visual Estimation of LASIK Flap Thickness.

PURPOSE: To assess the accuracy of surgeons' visual estimation of LASIK flap thickness when created by a femtosecond laser by comparing it to ultrasound measurements. METHODS: Surgeons were asked to visually estimate the thickness of a femtosecond flap during the procedure. Total corneal thickness was measured by ultrasound pachymetry prior to the procedure and the stromal bed was similarly measured after flap lifting. The estimates from three experienced surgeons (cornea fellowship trained and more than 5 years in practice) were compared to those of three cornea fellows, with each surgeon evaluating 20 eyes (120 total). Surgeons were not told the thickness of the flaps unless required for safety reasons. RESULTS: The average difference between visual and ultrasonic estimation of LASIK flap thickness was 15.20 µm. The flap was 10 µm thicker than estimated in 37% of eyes, 20 µm thicker in 17% of eyes, and 30 µm thicker in 10% of eyes. The largest deviation was 53 µm. There was no statistically significant difference between the accuracy of experienced surgeons and fellows (P = .51). CONCLUSIONS: There are significant differences between surgeons' visual estimates and ultrasonic measurements of LASIK flap thickness. Relying on these visual estimates may lead to deeper excimer laser ablation than intended. This could lead to thinner residual stromal beds and higher percent tissue altered than planned. The authors recommend that surgeons measure flaps intraoperatively to maximize accuracy and safety. [J Refract Surg. 2017;33(11):765-767.].

Safety and Efficacy of Sequential Intracorneal Ring Segment Implantation and Cross-linking in Pediatric Keratoconus.

PURPOSE: To evaluate the safety and visual outcome of intracorneal ring segment (ICRS) implantation followed by cross-linking in pediatric keratoconus patients. DESIGN: Retrospective interventional case series. METHODS: This retrospective study included pediatric patients (aged ≤14 years) with keratoconus and poor corrected distance visual acuity (CDVA) that underwent ICRS implantation and cross-linking (CXL). ICRS were inserted under topical anesthesia after creating a corneal tunnel with a femtosecond laser. Cross-linking was performed 1 month subsequently. Records were reviewed and data collected preoperatively and at 6 months, 1 year, 2 years, and 4 years postoperatively. RESULTS: Twelve patients (17 eyes; 10 male, 2 female) aged 9-14 years (mean age 12.3 years) received ICRS implantation followed by CXL. Follow-up times ranged from 6 months to 4 years after surgery. At the 6-month follow-up all eyes were evaluated; at the 1-year, 2-year, and 4-year follow-up 11, 10, and 7 eyes were evaluated, respectively. At the 6-month follow-up, mean CDVA in comparison to preoperative levels improved significantly (P = .001) from 0.30 ± 0.19 logMAR to 0.12 ± 0.1 logMAR; mean uncorrected distance visual acuity (UDVA) also improved significantly from 0.90 ± 0.50 logMAR to 0.43 ± 0.31 logMAR. A significant decrease in both keratometry readings and spherical equivalent (from -4.0 to -1.56 diopters) was also noted after ICRS insertion. At the 1-year, 2-year, and 4-year follow-up refractive values remained relatively stable in comparison to the 6-month follow-up, except for a minor but significant improvement in cylinder and, at 4 years, in UDVA. All patients tolerated the surgery well and no intraoperative or postoperative complications were reported, except for 1 ring segment that had to be removed after 2 years owing to vascularization and corneal thinning. CONCLUSION: ICRS implantation is a safe and effective procedure for visual rehabilitation in children with keratoconus and poor CDVA.

Choroidal tuberculoma as a presenting sign of tuberculosis.

Choroidal tuberculoma is a rare ocular form of tuberculosis (TB) that raises both a diagnostic and a therapeutical challenge, especially when occurring without other manifestations of the disease. This study reports the case of a 27-year-old woman who had a unilateral drop of vision (20/100) with ocular pain. Her fundus examination revealed an elevated juxtapapillary choroidal mass measuring 892 µm in diameter, as calculated by optical coherence tomography (OCT), and associated with a serous retinal detachment involving the macula. The diagnosis of choroidal tuberculoma was established by positive QuantiFERON-TB and tuberculin skin test. Laboratory and imaging workup ruled out pulmonary and systemic TB as well as other possible etiologies. Antituberculosis therapy was started and led to an improved visual acuity (20/30) and a shrinkage of the tuberculoma to a diameter of 499 µm at 3 months. This is one of the few reported cases of solitary choroidal tuberculoma in a patient with no other sign of TB. It sheds light on the place of OCT in the diagnosis and follow-up of the choroidal mass, in terms of measuring the size of the mass and revealing the associated serous retinal detachment and the distinctive "contact sign" between the neurosensory retina and the retinal pigment epithelium (RPE)-choriocapillaris layer surmounting the tuberculoma.

Corneal Resistance to Keratolysis After Collagen Crosslinking With Rose Bengal and Green Light.

Purpose: The purpose of this study was to evaluate the resistance to degradation by collagenase A of corneas that have been crosslinked with Rose Bengal and green light (RGX). Methods: The ex vivo crosslinking procedure was performed on enucleated rabbit corneas. Corneas were deepithelialized after applying 30% alcohol. Corneas were stained with Rose Bengal (RB, 0.1%) for 2 minutes and then exposed to green light (532 nm) at 0.25 W/cm2 for times to deliver doses of 50, 100, 150, or 200 J/cm2 (n = 5 per group). Five corneas were pretreated with riboflavin solution (0.1% riboflavin) for 15 minutes and irradiated with ultraviolet A (UVA) light (370 nm, 3 mW/cm2) for 30 minutes. Five corneas underwent only de-epithelialization and were otherwise untreated. Five corneas were stained with RB without light exposure. The central corneas of each group was removed with a 8.5-mm trephine and incubated at 37°C in 0.3% collagenase A solution. Time to dissolution of each cornea was compared across treatments. Results: Corneas treated with RGX were treated with light fluences of 50, 100, 150, and 200 J/cm2; these corneas dissolved completely at 8.3 ± 1.2, 11.1 ± 1.4, 12.4 ± 1.7, and 15.7 ± 1.8 hours, respectively. Corneas treated by riboflavin and UVA light dissolved at 15.7 ± 1.7 hours, and nontreated corneas dissolved at 6.1 ± 1.3 hours. Corneas treated with only RB (no green light) dissolved at 9.3 ± 1.7 hours. Compared with the untreated corneas, all of the RB groups and the riboflavin-UVA-treated group of corneas degraded statistically significantly slower than untreated corneas (P < 0.05). Conclusions: Crosslinking with RGX increased corneal resistance to digestion by collagenase comparable to that produced by riboflavin and UVA treatment.

Risk factors for loss of epithelial flap integrity in laser-assisted subepithelial keratectomy surgery.

PURPOSE: To evaluate risk factors leading to loss of epithelial flap integrity in laser-assisted subepithelial keratectomy (LASEK). SETTING: Boston Eye Group, Brookline, Massachusetts, USA. DESIGN: Retrospective case study. METHODS: This retrospective chart review was performed for LASEK surgeries that occurred between January 2009 and October 2013. Logistic regression was performed to determine whether epithelium preservation was correlated with age, sex, sphere, cylinder, spherical equivalent (SE), keratometry, and central corneal thickness (CCT). RESULTS: The study reviewed 1009 eyes of 509 patients with a mean age of 29.1 years ± 12.2 (SD). The mean preoperative spherical refraction was -4.7 ± 2.5 diopters (D), and the mean preoperative cylinder was -1.1 ± 0.8 D. The mean preoperative decimal corrected distance visual acuity was 1.01 ± 0.07. Single-sheet mobilization of the loosened epithelium flap was found in 72.3% of cases. Fragmented preservation events occurred in 17.6% of cases; the flap was discarded in 10.0% of cases. Epithelium preservation was significantly correlated with age (P = .048) but not with other parameters (P > .05 for sex, sphere, cylinder, SE, keratometry, CCT, and surgeon experience). Epithelial flap dissection was less likely to lead to a single epithelial sheet in patients older than 50 years than in younger patients (56.3% versus 74.9%). The mean postoperative decimal uncorrected distance visual acuity (UDVA) at 3 months was 0.98 ± 0.08. There was no statistical difference in postoperative UDVA between the undiscarded flap group and discarded flap group (P = .128). CONCLUSION: Successful dissection of single-sheet epithelial flap diminished with age. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Acute Corneal Hydrops 3 Years after Intra-corneal Ring Segments and Corneal Collagen Cross-linking.

This case report describes a 15-year-old male with allergic conjunctivitis and keratoconus, who underwent uneventful intra-corneal ring segment (ICRS) implantation and corneal collagen cross-linking (CXL) in the right eye. During the follow-up periods, the patient was noted to have several episodes of allergic conjunctivitis that were treated accordingly. At the 2 years postoperatively, he presented with another episode of allergic conjunctivitis and progression of keratoconus was suspected on topography. However, the patient was lost to follow-up, until he presented with acute hydrops at 3 years postoperatively. There are no reported cases of acute corneal hydrops in cross-linked corneas. We suspect the young age, allergic conjunctivitis and eye rubbing may be a risk factors associated with possible progression of keratoconus after CXL. Prolonged follow-up and aggressive control of the allergy might be necessary in similar cases.

An Update on the Safety and Efficacy of Corneal Collagen Cross-Linking in Pediatric Keratoconus.

Keratoconus is a degenerative disease that affects adolescents and young adults and presents with variable thinning and conical deformation of the corneal apex. The resultant irregular astigmatism can progress to levels that can significantly affect everyday activities and overall quality of life. Therefore, stopping the progression of the disease is an essential part in managing patients with keratoconus. Corneal collagen cross-linking is a minimally invasive procedure that stiffens the anterior corneal stroma by creating strong covalent bonds between collagen fibrils. Over the past decade, many studies have proved its safety and efficacy in halting keratoconus progression in adults. This review of the literature highlights the growing trend towards using this treatment in pediatric keratoconic patients. In children, keratoconus tends to be more severe and fast progression is often encountered requiring closer follow-up intervals. Standard cross-linking shows comparable results in children with a good safety-efficacy profile during follow-up periods of up to three years. Further research is needed to standardize and evaluate transepithelial and accelerated cross-linking protocols as these could be of tremendous help in a population where cooperation and compliance are major issues.

[Screening of diabetic retinopathy and maculopathy in Lebanese population using retinography and SD-OCT: The role of telemedicine]. / DÉPISTAGE de la RÉTINOPATHE et de la MACULOPATHIE DIABÉTIQUE au LIBAN par RÉTINOGRAPHIE et par SD-OCT: INTÉRÊT de la TÉLÉMÉDECINE.

PURPOSE: Diabetes and diabetic retinopathy (DR) are nowadays a major public health threat. The aim of this study is the screening of DR and diabetic maculopathy (DM) in a primary medical care center in Lebanon. We study also the interest of retinography and of SD-OCT in a telemedicine screening program. METHODS: This is a transversal study of patients with type 2 diabetes and with a regular follow-up in a primary medical care center in Beirut. For every patient, a retinography and an SD-OCT of the macula were obtained. Photos were sent by Internet to the Ophthalmology Department of Hôtel-Dieu de France to be evaluated by a retina specialist. Visual acuity and DR risk factors were assessed. RESULTS: 119 patients were included in this study. Mean age was 51.7 ± 10.2 years (54 females and 65 males). Mean diabetes duration was 12.15 years (SD 6:2). Mean of last three measurements of glycated hemoglobin was 8.1 ± 1.34%. Diabetic retinopathy was detected in 36 patients by retinography (30.3%). Diabetic maculopathy was confirmed by SD-OCT in 13 patients. Visual acuity was significantly correlated with central macular thickness. Mean diabetes duration, mean of last three measurements of glycated hemoglobin, peripheral neuropathy, positive macroalbuminuria and treatment with insulin were independently associated to diabetic retinopathy. CONCLUSION: Teleophthalmology is an efficient way for screening diabetic retinopathy in the Lebanese population. National screening program should be undertaken to adapt teleophthalmology on a larger scale.

Safety and efficacy of femtosecond laser-assisted arcuate keratotomy to treat irregular astigmatism after penetrating keratoplasty.

PURPOSE: To determine the refractive efficacy, predictability, stability, and complication rate of Intralase femtosecond laser-assisted astigmatic keratotomy (AK) for irregular astigmatism after penetrating keratoplasty (PKP). SETTING: Ophthalmology Department, Hôtel-Dieu, Paris, France. DESIGN: Retrospective case series. METHODS: Femtosecond laser-assisted AK was performed to treat high irregular astigmatism (>5.0 diopters [D]) after PKP. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, manifest refraction, vector analysis, and complications were evaluated. RESULTS: The study evaluated 62 eyes of 57 patients over a mean follow-up of 28 months ± 3.5 (SD). Preoperatively, the mean CDVA was 0.51 ± 0.26 logMAR and the mean UDVA was 0.98 ± 0.24 logMAR; 6 months postoperatively, the mean CDVA and UDVA improved to 0.40 ± 0.22 logMAR and 0.60 ± 0.2 logMAR, respectively (both P < .01). The mean preoperative absolute astigmatism was 7.1 ± 1.72 D; 6 months postoperatively, the mean refractive astigmatism was 2.6 ± 2.4 D (P < .001). The UDVA, CDVA, and astigmatism remained stable up to the end of follow-up. The efficacy index was 0.81 at 6 months and 0.67 at 2 years. There were 2 cases of microperforation, 3 cases of infectious keratitis, 3 graft rejection episodes, and 1 case of endophthalmitis. Overcorrection occurred in 12 eyes. CONCLUSIONS: Femtosecond laser-assisted AK was effective in reducing irregular astigmatism after PKP. Predictability of astigmatism correction is variable over time with a decrease in the efficacy index 2 years postoperatively. Refinement of the treatment nomogram for femtosecond laser-assisted AK for high astigmatism after PKP remains a major issue. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Safety and Visual Outcome of Visian Toric ICL Implantation after Corneal Collagen Cross-Linking in Keratoconus: Up to 2 Years of Follow-Up.

Purpose. To evaluate the long-term safety and clinical outcome of phakic Visian toric implantable collamer lens (ICL) insertion after corneal collagen cross-linking (CXL) in progressive keratoconus. Methods. This was a retrospective study of 30 eyes (19 patients), with progressive keratoconus, who underwent sequential CXL followed by Visian toric ICL implantation after 6 months. Results. At baseline, 6 eyes had stage I, 14 eyes stage II, and 10 eyes stage III keratoconus graded by Amsler-Krumeich classification. At 6 months after CXL, only K (steep) and K (max) decreased significantly from baseline, with no change in visual acuity or refraction. Flattening in keratometric readings was stable thereafter. There was significant improvement in mean uncorrected distance visual acuity (1.57 ± 0.56 to 0.17 ± 0.06 logMAR, P < 0.001) and mean corrected distance visual acuity (0.17 ± 0.08 to 0.11 ± 0.05 logMAR, P < 0.001) at 12 months after ICL implantation that was maintained at the 2-year follow-up. Mean cylinder power and mean spherical equivalent (SE) also decreased significantly after ICL implantation. A small hyperopic shift in SE (+0.25 D) was observed at 2 years that did not alter visual outcomes. Conclusions. Visian toric ICL implantation following CXL is an effective option for improving visual acuity in patients with keratoconus up to 2 years.

Extensive superior limbic keratoconjunctivitis in Graves' disease: case report and mini-review of the literature.

BACKGROUND: Superior limbic keratoconjunctivitis (SLK) is characterized as an inflammation of the superior bulbar conjunctiva with predominant involvement of the superior limbus and adjacent epithelial keratitis. METHODS: A 51-year-old woman, with a history of medically controlled Graves' disease was seen with an extensive SLK involving 5 mm of the superior cornea. RESULTS: Total remission was observed with topical steroids (DXM). Recurrence was observed 1 week after steroid discontinuation, and steroidal treatment was reintroduced with tapering over 1 month. Total remission was then observed for 1 year. CONCLUSION: Extensive keratitis and vascular pannus in SLK is rarely reported. This form could be treated with topical steroids. Tapering treatment remains essential for long-term success.

Effect of hemodialysis on visual acuity, intraocular pressure, and macular thickness in patients with chronic kidney disease.

BACKGROUND: The aim of this study was to evaluate the effects of hemodialysis (HD) on visual acuity, intraocular pressure (IOP), and central foveal thickness (CFT) in patients with chronic kidney disease. MATERIALS AND METHODS: Forty-nine eyes from 49 chronic kidney-disease patients were analyzed. Causes of chronic kidney disease included diabetes mellitus (n=9 patients), hypertensive nephrosclerosis (n=15 patients), and other causes (n=25 patients). All patients underwent HD in the Dialysis Unit of Hôtel-Dieu de France Hospital. Best-corrected visual acuity, CFT, and IOP were evaluated before and after HD. CFT was measured with spectral domain optical coherence tomography, and IOP was measured with Goldmann applanation tonometry. RESULTS: Neither decimal best-corrected visual acuity (pre-HD 0.71±0.32, post-HD 0.72±0.31; P=0.877) nor CFT (pre-HD 251.39±39.29, post-HD 253.09±39.26; P=0.272) significantly changed after HD. However, mean IOP significantly decreased from 13.99±2.48 before HD to 12.65±2.41 mmHg after HD (P=0.001). IOP change was significantly correlated with serum albumin levels (P=0.008) and weight changes (P=0.047). CONCLUSION: HD can affect various ocular parameters. This is particularly true of IOP, which decreases significantly following HD.