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PURPOSE: To describe 2-year results of deep intrastromal arcuate keratotomy with in situ keratomileusis (DIAKIK) for the treatment of high astigmatism after keratoplasty. METHODS: This prospective study included 20 eyes from 20 patients presenting with high astigmatism after keratoplasty. All were treated by two-step femtosecond laser surgery, with two intrastromal arcuate keratotomies and a corneal flap, followed a few months later by excimer photoablation after reopening of the flap. RESULTS: At 24 months, both uncorrected (UDVA) and corrected (CDVA) distance visual acuity had improved from 1.12 ± 0.42 logMAR (20/200 Snellen) before surgery to 0.58 ± 0.23 logMAR (20/80 Snellen) ( P < .001) and from 0.31 ± 0.26 logMAR (20/40 Snellen) to 0.20 ± 0.20 logMAR (20/32 Snellen) ( P = .04), respectively. The mean spherical equivalent improved from −5.01 ± 4.35 to −1.54 ± 2.42 diopters. The mean efficacy index was 0.63. The mean correction index was 0.93 ± 0.32. The mean flattening index was 1.09 ± 0.75 and the mean safety index was 1.39. No graft rejection or epithelial ingrowth was observed. CONCLUSIONS: This two-step procedure was an effective treatment for high astigmatism after keratoplasty. The use of both femtosecond and excimer lasers helped to avoid some complications that would have jeopardized the grafts. Refractive and topographic stability was good 2 years after surgery. [ J Refract Surg . 2019;35(4):239–246.]

Partial lead service line replacement (PLSLR) results in the addition of a new galvanic connection and can increase lead concentrations at the tap. Focus has been given to minimizing lead release after PLSLR, but little information is available on the impact of lead remedial actions on copper concentrations, especially before passivation occurs. The impact of water quality (decreased chloride-to-sulfate mass ratio from 0.9 to 0.3; addition of orthoP; pH increase to 8.3) on lead and copper concentrations was investigated after stagnation (30 min–336 h) in a pipe rig comparing full lead service line (LSL), and two configurations of partial LSLs (Cu-Pb and Pb-Cu). Results show different trends for lead and copper: maximum lead concentrations were reached in 16 h while copper concentrations continued to increase over 336 h. Lead release rates were also the highest in the first 16 h of stagnation and were strongly impacted by water quality and the configuration of PLSLR (Cu-Pb vs Pb-Cu). Increasing the sampling flow rate from 5 to 15 LPM drastically increased the particulate lead release (78-fold) in Pb-Cu configurations; this effect was however not observed in 100% Pb or Cu-Pb configurations. High velocity flushing prior to 16 h stagnation decreased total Pb release by a factor of 12-fold for Cu-Pb, 1.6-fold for Pb-Cu and 2.0-fold for 100% Pb. Results support the definition of sampling protocols targeted for the detection of lead and copper sources and the proscription of flushing prior to sampling.

PURPOSE: To assess epithelial corneal remodeling by anterior segment optical coherence tomography (AS-OCT) after intracorneal ring segments (ICRS) implantation in keratoconic eyes. METHODS: This prospective observational study included patients with keratoconus receiving ICRS of different arc lengths according to their tomographic pattern. AS-OCT and corneal topography (Scheimpflug camera) were performed before and 1, 3, and 6 months after surgery. Corneal pachymetry mapping was performed and total corneal and epithelial thicknesses (3-mm central and 16 points on 6-mm zone) were measured over the pupil center using AS-OCT. Topographic parameters were also assessed. RESULTS: A total of 68 keratoconic eyes were analyzed (Amsler-Krumeich stages 1 to 4) in four groups of 17 eyes: 210° ICRS, 320° ICRS, double 160° ICRS, and single 160° ICRS. Corneal pachymetry mapping revealed that epithelial thickness increased significantly in the internal zones juxtaposed to the ICRS without smoothing during the postoperative period ( P < .05). Mean maximum epithelial thickness increased from 67 ± 6 to 79 ± 7 µm for 210° ICRS, 66 ± 9 to 82 ± 4 µm for 320° ICRS, 63 ± 6 to 78 ± 7 µm for double 160° ICRS, and 62 ± 5 to 77 ± 5 µm for single 160° ICRS ( P < .0001). Significant epithelial thickening at the apex of the cone was observed in all groups ( P < .05). CONCLUSIONS: Significant epithelial thickening occurs after ICRS implantation adjacent to the ICRS to compensate for the ridge created with a thickening of epithelium over the cone due to regularization of the stromal surface. [ J Refract Surg . 2021;37(6):404–413.]

PURPOSE: To study corneal remodeling during the first 6 months after myopic small incision lenticule extraction (SMILE) with a 10% overcorrection nomogram, by spectral-domain optical coherence tomography (SD-OCT) and in vivo confocal microscopy (IVCM). METHODS: This prospective non-randomized observational study included 60 eyes from 30 patients treated by SMILE for low to moderate myopia. A 10% overcorrection nomogram was applied for all eyes. Epithelial and corneal thickness maps were obtained within the central 6 mm, by SD-OCT, at each visit. Lenticule thickness was calculated by subtracting the postoperative central stromal thickness from the preoperative central stromal thickness. IVCM was performed at each visit. RESULTS: The mean surgical refractive correction was −3.99 ± 1.50 diopters (D) before and −0.09 ± 0.37 D after surgery. Central epithelial thickness increased from 53.7 ± 4.0 to 57.1 ± 4.1 µm at 6 months after SMILE ( P < .001). The measured lenticule thickness was 16 ± 6.1 µm less than the programmed lenticule thickness ( P < .001). Both central epithelial hyperplasia and the mismatch between measured and programmed lenticule thickness were positively correlated to the degree of myopia ( r 2 = 0.60, P < .001 and r 2 = 0.47, P < .001, respectively). Fibrosis at the interface was not correlated with epithelial thickening ( r 2 = 0.06, P = .29) or lenticule thickness error ( r 2 = 0.07, P = .22). CONCLUSIONS: Both epithelial thickening and the mismatch between the targeted and achieved lenticule thickness resulted in a slight undercorrection with a 10% overcorrection nomogram in low and moderate myopia. Fibrosis at the interface was not responsible for lenticule thickness error. Additional overcorrection is required to increase accuracy. [ J Refract Surg . 2020;36(9):597–605.]

New direct oral anticoagulants (DOAC) have been approved for treatment and prevention of some thromboembolic diseases: acute and chronic phase of thromboembolic disease, deep venous thrombosis prophylaxis in orthopedic surgery and prevention of stroke in patients with atrial fibrillation. These molecules are an alternative to heparins and vitamin K antagonists. Among these, rivaroxaban (Xarelto®, Bayer Schering Pharma) is a direct factor Xa inhibitor, and dabigatran etexilate (Pradaxa®, Boehringer Ingelheim) is a direct free thrombin inhibitor. These molecules are almost the ideal anticoagulant: oral administration, few drug and food interactions, wide therapeutic target, and especially no lab monitoring. However, their use remains associated with hemorrhagic complications such as gastrointestinal, intracranial or urinary hemorrhages. We describe two clinical cases of spontaneous choroidal hemorrhage in patients treated with direct oral anticoagulants (rivaroxaban and dabigatran etexilate) for atrial fibrillation. These cases show that an ocular hemorrhagic risk exists with these drugs. Patients treated with DOAC should have the therapeutic dose adjusted based on creatinine clearance. Special monitoring should be performed in patients with age-related macular degeneration or with hypertension even though meta-analysis shows that the risk of intraocular bleeding is reduced by 22% compared with warfarin.

PURPOSE: To evaluate and compare epithelial remodeling after standard corneal cross-linking (S-CXL) and iontophoresis-assisted CXL (I-CXL) in eyes with keratoconus by anterior segment optical coherence tomography (AS-OCT). METHODS: In this prospective, observational study, AS-OCT and corneal topography were performed before and 1, 3, and 6 months after surgery. Corneal pachymetry was performed and epithelial and stromal thicknesses (central and 16 points on the 6-mm central zone) and the maximum simulated keratometry value (Kmax) were measured. RESULTS: Two groups of 30 patients (60 eyes total) with progressive keratoconus underwent S-CXL or I-CXL. Before surgery, both groups of patients presented with an irregular epithelial thickness profile. At 6 months postoperatively, localized corneal epithelial thinning was observed in the superior ( P = .026), inferior ( P = .034), inferonasal ( P = .024), and nasal ( P = .035) areas at 3 mm and in the superior ( P = .039), nasal ( P = .043), and inferior ( P = .01) areas at 6 mm in the SCXL group. Localized corneal epithelial thinning was observed at 3 ( P = .04) and 6 ( P = .01) mm in the inferior area in the I-CXL group. No significant stromal changes were observed for either group. Kmax was stable in both groups at 6 months. CONCLUSIONS: Significant epithelial remodeling occurs after S-CXL, resulting in a thinner, more regular thickness profile than after I-CXL. Epithelial thickness profile measurements after I-CXL could be used as an adjunctive follow-up tool for monitoring the efficacy of CXL in progressive keratoconus. [ J Refract Surg. 2018;34(8):551–558.]

Infectious keratitis are a frequent cause of ocular morbidity. Today, new treatments are necessary to combat the emergence of antibiotic resistant germs. Corneal collagen cross-linking has been suggested to treat corneal infectious (PACK-CXL). Its action would be both antimicrobial and protective for the cornea, increasing its biochemical resistence to proteolytic enzymes. In vivo, PACK-CXL might demonstrate good efficacy against bacterial keratitis, contrary to herpetic keratitis for which it is contraindicated. For fungal or amoebic keratitis, results are uncertain regarding its safety and efficacy. The purpose of this paper is to clarify the use of corneal collagen cross-linking to treat infectious keratitis.

To compare the pupil dynamics of an intracameral combination of 2 mydriatics and 1 anesthetic (Mydrane) to a standard topical regimen for cataract surgery.Sixty-two centers in Europe and 6 centers in Algeria.Prospective case series.Pupil size measurements were performed in 2 randomized studies (phase 2 and phase 3) under masked conditions (recorded videography, masked reading center). The outcomes in the phase 2 study supported evaluation of the timeframe to obtain pupil dilation and the phase 3 study provided results on mydriasis stability.Phase 2 and phase 3 comprised 139 patients and 591 patients, respectively. After intracameral combination administration, 95% of the pupil dilation was achieved within a mean of 28.6 seconds ± 4.6 (SD). At the beginning of capsulorhexis creation, the mean pupil diameter was larger than 7.0 mm in both groups. The intraoperative pupil diameter remained stable in the intracameral combination group and decreased in the topical group. The mean change in pupil size just before capsulorhexis to the end of surgery (just before cefuroxime injection) was -0.22 ± 0.72 mm and -1.67 ± 0.98 mm, respectively. No clinically significant change in pupil diameter (change1.0 mm) occurred in the majority of the intracameral combination group (89.3%) compared with the topical group (26.8%).Intracameral combination of 2 mydriatics and 1 anesthetic is an alternative to topical mydriatics for cataract surgery. The prompt onset of pupil dilation and the stable mydriasis induced by this drug combination improved the intraoperative conditions during crucial steps, such as intraocular lens implantation.

Unilateral corneal ectasia developed after small-incision lenticule extraction for mild myopia in a 43-year-old man with preoperative asymmetric astigmatism. The ectasia was diagnosed 4 years postoperatively. Preoperative data showed asymmetric astigmatism with no signs of forme fruste keratoconus. Inferior anterior curvature steepening exceeded 2.00 diopters without bulging of the posterior curvature, and pachymetric thickness exceeded 515 μm. Corneal ectasia can occur after small-incision lenticule extraction in patients older than 40 years with preoperative asymmetric astigmatism.

Purpose We describe the first case of minimally invasive corneal neurotization with the great auricular nerve (GAN) to treat unilateral neurotrophic keratopathy. We assessed corneal sensation and reinnervation by esthesiometry and confocal microscopy over 12 months of follow-up, and we provide a detailed description of the surgical technique. Methods Corneal neurotization was successfully achieved with the ipsilateral GAN in a 58-year-old woman. Cochet-Bonnet esthesiometry and in vivo confocal microscopy were performed before and after corneal neurotization, to monitor the recovery of corneal sensation and corneal reinnervation by subbasal nerve fibers. Results Neurotrophic keratopathy was a complication of the surgical treatment of meningioma. Before surgery, the patient had no corneal sensation or corneal innervation. Six months after surgery, confocal microscopy confirmed regrowth of a large number of nerve fibers in the subepithelial space of the cornea. Nine months after surgery, a central esthesiometry score of 10-mm was attained. Conclusions Corneal neurotization leads to reinnervation of the cornea and recovery of ocular sensation in adults. The GAN is suitable for use in corneal neurotization because of its anatomical proximity and the low level of associated morbidity. Confocal microscopy demonstrated the occurrence of corneal reinnervation, which preceded the recovery of corneal sensation.

Purpose To provide quantitative parameters for assessment of human donor corneal stroma by imaging stromal features of diseased and normal human corneas with full-field optical coherence microscopy (FFOCM), using confocal microscopy (CM) and histology as reference techniques. Methods Bowman's layer (BL) thickness and keratocyte density were assessed ex vivo in 23 human donor corneas and 27 human pathological corneas (keratoconus and other corneal disorders) with FFOCM, CM and histology. Stromal backscattering was assessed with FFOCM. Additionally, 10 normal human corneas were assessed in vivo with CM. Results In FFOCM, the logarithm of the normalized stromal reflectivity was a linear function of stromal depth (R2 = 0.95) in human donor corneas. Compared with keratoconus corneas, human donor corneas featured higher BL thickness (p = 0.0014) with lower coefficient of variation (BL-COV; p = 0.0002), and linear logarithmic stromal reflectivity with depth (higher R2, p = 0.0001). Compared with other corneal disorders, human donor corneas featured lower BL-COV (p = 0.012) and higher R2 (p = 0.0001). Using the 95% confidence limits of the human donor cornea group, BL thickness 18.6% (79%; 100%) and R2

Background To evaluate quantitative and qualitative changes in subbasal corneal nerves (SBN) via in vivo confocal microscopy (IVCM) in patients with Sjogren syndrome dry eye (SSDE) treated with topical cyclosporine A (CsA). Design Prospective, observational, non-randomized study. Participants Thirty eyes of 30 patients with SSDE refractory to conventional treatment treated with CsA 0.05% twice daily for six months. Fifteen eyes of 15 healthy, age and gender matched, volunteers constituted the control group at baseline. Methods A clinical evaluation of dry eye (DE), corneal sensation using Cochet-Bonnet esthesiometry and IVCM analysis of the central cornea were performed prospectively at baseline for all patients, and after six months of treatment with CsA. Main outcome measures Density, number, reflectivity and tortuosity of SBN, dendritic cell (DC) density, esthesiometry, and DE signs and symptoms. Results Topical CsA 0.05% improved clinical signs and symptoms, and increased corneal sensitivity. Following treatment, SBN density was significantly increased (P

To analyze refractive results after hyperopic presbyopia surgery by Q-factor modulation without additive monovision.Quinze-Vingts National Ophthalmology Hospital, Paris, France.Prospective nonrandomized study.Forty-five hyperopic presbyopic patients not tolerating monovision were included. The target for the dominant eye was emmetropia, whereas that for the nondominant eye was emmetropia associated with a target Q factor of -0.8. The postoperative follow-up included assessments of spherical equivalent (SE) refraction, monocular and binocular corrected and uncorrected (UDVA) distance visual acuities, and binocular corrected and uncorrected (UNVA) near visual acuities. Corneal pachymetry, topography, aberrometry and an analysis of patient satisfaction were performed at the 12-month examination.The study comprised 90 eyes of 45 consecutive patients. The mean age at surgery was 53.8 years ± 4.99 (SD). The mean preoperative SE was +2.33 ± 1.16 diopters (D) in the dominant eyes and +2.26 ± 1.17 D in the nondominant eyes. At 12 months postoperatively, 42 patients (93%) had a binocular UDVA of Snellen 20/20 and 37 patients (82%) had a binocular UNVA of Jaeger 2 (Parinaud 3). The mean SE at 12 months was -0.22 ± 0.35 D in the dominant eyes (P .0001) and -0.83 ± 0.50 D in the nondominant eyes (P .0001). Two eyes required retreatment. Overall, 39 patients (87%) said that they were satisfied and would recommend the intervention.The Q-factor modulation without additive monovision aims to compensate for presbyopia by changing the Q factor of the nondominant eye to generate a greater depth of field in hyperopic presbyopic patients who are unable to tolerate monovision. The visual outcomes and quality of vision were satisfactory, and only a few patients required additional correction.

Summary Standard corneal collagen crosslinking (S-CXL) is a safe, approved procedure, but it may result in severe pain, early vision loss and possible complications, such as infectious or sterile keratitis , in some cases. We describe four cases of sterile infiltrates after uneventful S-CXL for keratoconus , from diagnosis to medical management with six months of follow-up, reporting their pathophysiological features, and comparing our findings with published reports. We discuss various possibilities for diagnosing sterile infiltration more rapidly. In terms of the pathophysiology of sterile infiltrate formation, we separated our patients into two types, one with sterile infiltrate from an antigen reaction and the other with sterile infiltrate due to excessive scarring. Early local steroid treatment resulted in a good visual outcome in our cases.

PURPOSE To determine the anatomic criteria for diagnosing keratoconus progression by corneal optical coherence tomography (OCT). SETTING Quinze-Vingts National Ophthalmology Hospital, Paris, France. DESIGN Prospective case series. METHODS Scanning-slit corneal topography (Orbscan II) and Fourier-domain corneal OCT (RTVue) were performed in eyes with mild to moderate keratoconus (progressive or nonprogressive [stable] ectasia) at each examination to assess the keratoconus. Disease progression was defined as an increase of at least 1.0 diopter (D) in the steepest keratometry (K) measurement over 6 months. RESULTS Of the 134 eyes of 134 patients with mild to moderate keratoconus, 98 had had progressive ectasia and 36 nonprogressive ectasia. The mean maximum K increased significantly in the progressive group (2.1 D ± 1.2 [SD], P

The cornea has the densest sensory innervation of the body, originating primarily from neurons in the trigeminal ganglion. The basic principles of cornea nerve patterning have been established many years ago using classic neuroanatomical methods, such as immunocytochemistry and electrophysiology. Our understanding of the morphology and distribution of the sensory nerves in the skin has considerably progressed over the past few years through the generation and analysis of a variety of genetically modified mouse lines. Surprisingly, these lines were not used to study corneal axons. Here, we have screened a collection of transgenic and knockin mice (of both sexes) to select lines allowing the visualization and genetic manipulation of corneal nerves. We identified multiple lines, including some in which different types of corneal axons can be simultaneously observed with fluorescent proteins expressed in a combinatorial manner. We also provide the first description of the morphology and arborization of single corneal axons and identify three main types of branching pattern. We applied this genetic strategy to the analysis of corneal nerve development and plasticity. We provide direct evidence for a progressive reduction of the density of corneal innervation during aging. We also show that the semaphorin receptor neuropilin-1 acts cell-autonomously to control the development of corneal axons and that early axon guidance defects have long-term consequences on corneal innervation.SIGNIFICANCE STATEMENTWe have screened a collection of transgenic and knockin mice and identify lines allowing the visualization and genetic manipulation of corneal nerves. We provide the first description of the arborization pattern of single corneal axons. We also present applications of this genetic strategy to the analysis of corneal nerve development and remodeling during aging

We report the clinical features and management of a patient with severe bilateral infectious keratitis developing after simultaneous bilateral small-incision lenticule extraction. A 39-year-old man was referred to our emergency department 2 days after a small-incision lenticule extraction procedure for moderate myopia. He reported decreased vision, photophobia, and pain bilaterally. Visual acuity was counting fingers in the right eye and hand motion in the left eye. Slitlamp examination showed multiple white corneal infiltrates at the corneal cap–stromal bed interface. The interface was first rinsed with povidone–iodine 10.0% and then with vancomycin (50 mg/mL). Fortified antibiotics eyedrops administration was initiated. Cultures showed Streptococcus pneumonia. Anterior segment spectral-domain optical coherence tomography scans were performed daily. Once the infection was controlled 4 days later, corticosteroids eyedrops were begun. Three months postoperatively, the patient had a corrected distance visual acuity of 20/32 in the right eye and 20/25 in the left eye. Financial Disclosure None of the authors has a financial or proprietary interest in any material or method mentioned.

Cyclosporine A (CsA) is a cyclic undecapeptide, which is an immunosuppressive drug in the calcineurin inhibitor class. CsA was initially used as a systemic immunosuppressant to minimize rejection of solid organ transplants. In ophthalmology, topically applied CsA was first used to inhibit corneal allograft rejection in the 1980s and later in various inflammatory ocular surface disorders (OSD). Currently, topical ophthalmic CsA is available as a licensed commercial emulsion or is prepared by hospital pharmacies with concentration ranging from 0.05 to 2%. Many of its pharmacological effects on the ocular surface are direct consequences of its ability to inhibit T ciclosporine activation and apoptosis. Topical CsA differs from topical steroids in its favourable local and systemic tolerability at the concentrations used. Most clinical studies have evaluated topical CsA in moderate to severe dry eye disease (DED) and demonstrated its efficacy for improvement of signs and symptoms, thus providing the sole indication for market approval and treatment protocols. For the other indications - corneal graft rejection, blepharitis, allergic or viral keratitis, and ocular surface disease due to graft versus host disease or post-operative DED - evidence-based medicine remains unclear due to the lack of major randomized controlled trials. Despite the lack of standardized protocols or market approval for these conditions, numerous studies suggest clinical efficacy.

This work aimed to evaluate the ability of four regulatory sampling protocols to accurately determine weekly water lead levels (WLLs) of exposure at the kitchen tap in twenty-nine households with or without a lead service line (LSL). Proportional sampling was used as the gold standard to which the other protocols, 5-min flush, 30-min stagnation, 6-h stagnation and random daytime were compared. Random daytime samples provided mean WLLs closest to true exposure in the households monitored overall compared to other sampling protocols. Strikingly, mean WLLs after 5 min of flushing underestimated lead exposure by 47%. Supporting these observations, water usage patterns revealed that full flushing only occurs in 3.4% of usage events within the service line and in 0.26% at the tap. The time between usage events in the service line was approximately 30 min but the 30-min protocol tended to slightly underestimate WLLs. These differences were explained by flushing prior to the 30-min stagnation sampling, which limited the contribution of the LSL to WLLs. Furthermore, the average stagnation at the kitchen time was 106 min and usage events rarely exceeded the water volume within premise plumbing (1.1 L). Mean WLLs after 6 h of stagnation without flushing overestimated exposure by 29% but provided a conservative indicator of WLLs of exposure.

The KAMRA small-aperture corneal inlay can compensate for presbyopia. A small number of complications have been reported, including glare, halos, decentration, iron deposition, compromised distance and night vision, infectious keratitis and reversal corneal haze. We describe a case of corneal fibrosis after small-aperture corneal inlay implantation and its persistence after late explantation. The postoperative period was uneventful, with good uncorrected near and distance visual acuities. Six years after implantation, the patient reported vision loss in the left eye. A slitlamp evaluation and optical coherence tomography showed stromal opacity and a stromal hyperreflective signal at the level of the small-aperture corneal inlay. The corneal inlay was removed, but persistent decreased visual acuity and fibrosis were observed even 8 months after explantation and did not respond to steroids. Long-term monitoring with multimodal imaging methods is important to detect late adverse events after small-aperture corneal inlay implantation.

Profile, regulatory, and investigative sampling were completed in six utilities to study the impact of partial and full lead service line replacements (LSLRs) on water lead levels (WLLs) and consumer's exposure. As compared to households with no replacement, lead release after partial LSLR (PLSLR) was generally greater in the short term (3-50 days), and comparable or lower in the medium (2 years) and long-term (2 years). This was mainly explained by insufficient time elapsed to stabilize scales after disturbances to the service line. One utility showed sustained lead release over 18 months after PLSLR. Moreover, the reduction in WLLs was small when analyzing results for the same households. As a comparison, full LSLR decreased WLLs drastically and immediately. The occurrence of low (0-5 μg/L) to high (≥50 μg/L) WLLs in the profiles varied between households and reflected the variability of exposure among households in the same system. Using this probability of occurrence, the distribution of WLLs of exposure was estimated for households with or without a PLSLR, and used to model young children blood lead levels (BLLs) for both groups of households. The range of modeled BLLs decreased slightly for households with PLSLR, but still overlapped the range estimated for households with no replacement. This analysis suggests that, in a system, PLSLRs do not reduce young children blood lead levels except in a fraction of households.

Long-term (155 weeks) Pb concentrations, following partial lead service lines replacements (PLSLR), were measured in a flow through pilot made of harvested lead service lines (LSL) from the distribution system of the City of Montreal. The present study also investigates how release of Pb from full and partial LSLs is influenced by: pipe diameter, decrease in chloride-to-sulfate mass ratio (CSMR) from 0.9 to 0.3, addition of orthophosphate (1 mg P/L), and increase in pH to 8.3. Pb concentrations were measured after 16 h of stagnation and under flow conditions. In this study, Pb concentrations did not decrease, in the long term, after partial LSL replacement. Moreover, the most effective corrosion control treatment in full LSLs was the addition of orthoP. In contrast, the decrease of the CSMR best reduced lead release from partial LSLs. The impact of pipe configuration therefore influenced the effectiveness of corrosion control treatments. It is noteworthy that the increase in Pb concentrations following PLSLR were attributed to particulate Pb release from the galvanic section of the pipe. The occurrence of galvanic corrosion, caused by the connection between Pb and copper pipes, adds a new source of Pb in the partial LSL. At least, this new source of lead has to be offset by the removal of a long enough section of LSL during PLSLR. Full LSL replacements may be warranted to minimize the exposure of consumers to elevated Pb levels caused by galvanic corrosion in LSLs.

Integrons are genetic elements that can acquire and rearrange gene cassettes. The bla BEL-1 gene encodes an extended-spectrum β-lactamase, BEL-1, that is present at the second position of the variable region of class 1 integrons identified in Pseudomonas aeruginosa . The mobility of the bel-1 gene cassette was analyzed under physiological conditions and with the integrase gene being overexpressed. Cassette mobility in Escherichia coli was detected by excision/integration into the recipient integron In 3 on the conjugative plasmid R388 with the overproduced integrase. Despite several antibiotic pressures, the bel-1 cassette remained at the second position in the integron, highlighting its stability in P. aeruginosa . Overexpression of the integrase gene in E. coli induced bel-1 cassette recombination. However, cassettes containing two genes ( bla BEL-1 and smr2 or bla BEL-1 and aacA4 ) were excised, suggesting that the bel-1 cassette attC site was defective. We show that bel-1 is a stable gene cassette under physiological growth conditions, irrespective of the selective antibiotic pressure, that may be mobilized upon overexpression of the integrase gene.

Purpose To define the optical coherence tomography (OCT) corneal changes predisposing to acute corneal hydrops among patients with advanced keratoconus. Design Retrospective cohort study. Participants A total of 191 advanced keratoconic eyes from 191 patients with advanced keratoconus cases were studied. Methods Data collected from patients with advanced keratoconus cases were studied during a minimum period of 24 months of follow-up. High-resolution Fourier-domain corneal OCT (5 μm of axial resolution) and corneal topography were performed every 4 months during the follow-up. Several anatomic features at the keratoconus cone were analyzed with OCT, including epithelial and stromal thicknesses, the aspect of Bowman's layer, the presence of Vogt's striae, and stromal opacities. A comparative analysis between anatomic corneal features in eyes that developed corneal hydrops and those that did not develop this complication during the follow-up was performed. Main Outcome Measures Evaluation of anatomic corneal changes at risk of developing a corneal hydrops on the basis of OCT findings. Results Eleven cases of corneal hydrops (5.8%) occurred in our series during a mean follow-up of 30 months (24–36 months). All of these patients were male and younger (23.7±5.9 years) than patients with no acute keratoconus (32.7±11.3 years). Increased epithelial thickening with stromal thinning at the conus and the presence of anterior hyperreflectives at the Bowman's layer level were significantly associated with corneal hydrops, whereas the presence of corneal scarring was a preventive factor. At the healing stage, a pan-stromal scar occurs, with a significant stromal thickening and cornea flattening. Conclusions Increased epithelial thickening, stromal thinning at the keratoconus cone, anterior hyperreflectives at the Bowman's layer level, and the absence of stromal scarring are associated with a high risk of developing corneal hydrops. These aspects should be taken into account by the clinician in the evaluation of keratoconus eyes and in the planning of corneal keratoplasty.

Corneal collagen crosslinking (CXL) is, at present, the only treatment that can slow or even stop the progression of keratoconus. It uses riboflavin and ultraviolet A (UVA) to create covalent bonds ("crosslinks") between collagen fibrils thus increasing corneal rigidity. Although to date there has been no direct evidence of intrastromal corneal crosslinking, several studies have reported the safety and efficacy of the conventional CXL protocol. This protocol is indicated for progressive keratoconus with a minimal corneal thickness (without the epithelium) of at least 400 μm. It should be performed as early as possible in patients under 18 years with keratoconus or with post-LASIK ectasia. Because of the epithelial debridement, it may rarely induce complications such as infectious keratitis or stromal scars. A variety of new protocols is under investigation and may reduce the rate of these complications. In addition, combination of CXL with other surgical treatments (intracorneal ring segments or photorefractive keratectomy) may improve visual outcomes in patients with keratoconus. Finally, the antimicrobial and anti-edematous properties of CXL have been shown, suggesting new therapeutic indications of this procedure such as infectious keratitis or stromal edema in the future.

Thirty-three households were monitored in a full-scale water distribution system, to investigate the impact of recent (2 yr) or old partial lead service line replacements (PLSLRs). Total and particulate lead concentrations were measured using repeat sampling over a period of 1-20 months. Point-of-entry filters were installed to capture sporadic release of particulate lead from the lead service lines (LSLs). Mean concentrations increased immediately after PLSLRs and erratic particulate lead spikes were observed over the 18 month post-PLSLR monitoring period. The mass of lead released during this time frame indicates the occurrence of galvanic corrosion and scale destabilization. System-wide, lead concentrations were however lower in households with PLSLRs as compared to those with no replacement, especially for old PLSLRs. Nonetheless, 61% of PLSLR samples still exceeded 10 μg/L, reflecting the importance of implementing full LSL replacement and efficient risk communication. Acute concentrations measured immediately after PLSLRs demonstrate the need for appropriate flushing procedures to prevent lead poisoning.

To compare the efficacy, safety, and microstructural corneal changes during 2 years after conventional corneal collagen cross-linking (C-CXL) and transepithelial corneal CXL by iontophoresis (I-CXL) for keratoconus.Eighty eyes of 80 patients with progressive keratoconus were treated by C-CXL (n = 40) or I-CXL (n = 40). Patients were investigated before surgery and 1, 3, 6, 12, and 24 months after treatment. We measured central corneal thickness and maximal simulated keratometry values (Kmax) and performed specular microscopy and in vivo confocal microscopy at each time point. The demarcation line was assessed 1 month after treatment.Kmax remained stable after I-CXL during the entire study period (P = 0.56), whereas the average keratometry increased by 0.2 diopter (50.9 ± 5.6-51.1 ± 5.2). Kmax significantly decreased 1 (P = 0.02) to 2 years (P0.01) after C-CXL, with an average decrease of 1.1 diopters (49.9 ± 4.5-48.8 ± 4.2). The failure rate of I-CXL was 20% and that of C-CXL 7.5%. The demarcation line was superficially visible in 35% of cases after I-CXL compared with 95% of cases after C-CXL. Endothelial cell density and central corneal thickness remained stable during the entire study period. The change in Kmax 2 years after C-CXL and I-CXL and the preoperative Kmax were negatively correlated (r = 0.14, P = 0.013, and r = 0.17, P = 0.007, respectively).I-CXL halted progression of keratoconus less efficiently than did C-CXL after 2 years of follow-up. Longer prospective studies are still needed to ensure I-CXL efficacy.

Resume Objectif Comparer a l’aide de l’Orbscan et de la pachymetrie ultrasonique les caracteristiques de la cornee dans un groupe de myopes forts et dans un groupe sans ametropie spherique. Methodes La pachymetrie ultrasonique et l’Orbscan ont ete prospectivement realises sur 105 myopes forts (longueur axiale superieure a 26 mm) et sur 105 patients sans ametropie spherique (equivalent spherique inferieur a 1,25D en valeur absolue, independamment du cylindre). Les donnees de l’astigmatisme ont ete transformees en coordonnees rectangulaires dans un plan dioptrique. L’axe a ete decompose en 2 composantes (directe/inverse et oblique) analysees par les fonctions trigonometriques (Cos2axe et Sin2axe). L’enantiomorphisme (symetrie en miroir) des 2 yeux d’un patient a ete quantifie par une distance euclidienne pour la localisation du point le plus fin et par la difference (en valeur absolue) entre la somme des 2 axes et 180° pour l’astigmatisme. Resultats Dans le groupe myope, la longueur axiale etait de 27,82 mm (±2,14 ; 26,00 a 34,06) et l’equivalent spherique subjectif de −9,00D (±3,46 ; −4,71 a −19,82). L’astigmatisme corneen moyen etait de +0,92D × 91,3° pour les myopes et de +0,65D × 89,3° pour l’autre groupe. Le cylindre corneen etait significativement plus eleve chez les myopes (1,44D contre 0,91D ; p p = 0,03) contrairement a la keratometrie moyenne et a la keratometrie minimale qui ne presentaient pas de difference. Aucune difference significative entre les 2 groupes n’a ete retrouvee pour l’epaisseur centrale (myopes : 540,2 μm versus 546,9 μm ; p = 0,10), l’epaisseur peripherique, le diametre corneen, l’irregularite corneenne, l’asphericite ou l’astigmatisme irregulier. Le degre d’enantiomorphisme ne presentait aucune difference entre les 2 groupes. Dans le groupe myope, la correlation avec la longueur axiale etait uniquement significative pour l’equivalent spherique ( r = −0,86 ; p r = 0,16 ; p = 0,04). Conclusion A l’exception de la toricite, la cornee des myopes forts est similaire a la cornee des yeux sans ametropie spherique. Contrairement a l’elongation du segment posterieur, le developpement de la myopie forte ne semble pas concerner la cornee. En perturbant le mecanisme d’emmetropisation de l’œil, la toricite de la cornee pourrait etre un facteur favorisant l’evolution vers la myopie forte.

Purpose To evaluate an automated process to find borders of corneal basal epithelial cells in pictures obtained from in vivo laser scanning confocal microscopy (Heidelberg Retina Tomograph III with Rostock corneal module). Methods On a sample of 20 normal corneal epithelial pictures, images were segmented through an automated four-step segmentation algorithm. Steps of the algorithm included noise reduction through a fast Fourier transform (FFT) band-pass filter, image binarization with a mean value threshold, watershed segmentation algorithm on distance map to separate fused cells and Voronoi diagram segmentation algorithm (which gives a final mask of cell borders). Cells were then automatically counted using this border mask. On the original image either with contrast enhancement or noise reduction, cells were manually counted by a trained operator. Results The average cell density was 7722.5 cells/mm2 as assessed by automated analysis and 7732.5 cells/mm2 as assessed by manual analysis (p = 0.93). Correlation between automated and manual analysis was strong (r = 0.974 [0.934–0.990], p

Topography-guided transepithelial photoablation using the Wavelight Allegretto excimer laser was performed in a patient whose corrected distance visual acuity (CDVA) was severely impaired by superficial fibrosis and major irregular corneal astigmatism. One month postoperatively, the CDVA had improved from 20/400 to 20/50 with spectacle correction and 20/25 with a rigid gas-permeable contact lens. Postoperative corneal topography showed a substantial reduction in the irregular component of the astigmatism. Optical coherence tomography analysis revealed a major decrease in the central fibrotic scarring around the corneal visual axis. No complication occurred, and the patient was very satisfied. Topography-guided custom ablation seems to be a safe and efficient technique for reduction of the irregular component of corneal astigmatism in a scarred cornea. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Keratoplasty may induce major spherical refractive error related to abnormal corneal radius of curvature (CRC).Two hundred and thirty-eight consecutive eyes of 238 patients with clear graft and at least one postoperative Orbscan examination performed after suture removal (average follow-up time, 86 months) were retrospectively analyzed. Anterior lamellar keratoplasties (ALK group, n = 119) and penetrating keratoplasties (PK group, n = 119) were matched for preoperative diagnosis and lens status.The average postoperative, suture-out, Orbscan 3-mm CRC was 7.17 mm with a wide 95 % confidence interval [6.26 mm; 8.37 mm]. It was 7.05 mm in the ALK group and 7.31 mm in the PK group (p 0.01). In the ALK group, this figure was 7.00 mm for oversized grafts and 7.67 mm for non-oversized grafts (p 0.001). CRC values were significantly lower for eyes with keratoconus (7.00 mm) or stromal scar after infectious keratitis (7.06 mm) compared with stromal scar after trauma (7.74 mm) or stromal dystrophies (8.17 mm). Values were significantly lower for big-bubble ALKs (6.92 mm) and manual dissection-ALKs (7.14 mm) compared with PKs (7.31 mm) and microkeratome-assisted ALKs (7.45 mm). The average Orbscan 3-mm SimK cylinder, irregularity, and refractive power symmetry index were, respectively, 4.7 D/4.8 D/1.9 D for ALKs and 5.2 D/4.8 D/1.8 D for PKs (p = 0.99).The CRC is lower after ALK compared with PK, and features important variability. In eyes with ALK, non-oversized grafts result in postoperative CRC close to normal values and corneal diseases associated with stromal thinning and DALK result in lower postoperative CRC.

Objective To study corneal morphologic changes in a large keratoconic population and to establish a structural optical coherence tomography (OCT) classification. Design Cross-sectional, observational study. Participants A total of 218 keratoconic eyes from 218 patients and 34 eyes from 34 normal subjects. Methods A Fourier-domain OCT system with 5-μm axial resolution was used. For each patient, 3 high-resolution scans were made across the keratoconus cone. All scans were analyzed by keratoconus specialists who were not given access to patients' clinical and topographic data, and who established an OCT classification. The reproducibility of the classification and its correlation with clinical and paraclinical characteristics of patients with keratoconus were evaluated. The OCT examinations were performed every 4 months to follow up structural corneal changes. Main Outcome Measures Evaluation of the structural corneal changes occurring in keratoconus cases with various stages of severity based on OCT findings. Results Fourier-domain OCT classification containing 5 distinct keratoconus stages is proposed. Stage 1 demonstrates thinning of apparently normal epithelial and stromal layers at the conus. Stage 2 demonstrates hyperreflective anomalies occurring at the Bowman's layer level with epithelial thickening at the conus. Stage 3 demonstrates posterior displacement of the hyperreflective structures occurring at the Bowman's layer level with increased epithelial thickening and stromal thinning. Stage 4 demonstrates pan-stromal scar. Stage 5 demonstrates hydrops; 5a, acute onset: Descemet's membrane rupture and dilaceration of collagen lamellae with large fluid-filled intrastromal cysts; 5b, healing stage: pan-stromal scarring with a remaining aspect of Descemet's membrane rupture. The reproducibility of the classification was very high between the corneal specialist observers. Clinical and paraclinical characteristics of keratoconus, including visual acuity, corneal epithelium and stromal thickness changes, corneal topography, biomechanical corneal characteristics, and microstructural changes observed on confocal microscopy, were concordant with our OCT grading. Conclusions Optical coherence tomography provides an accurate assessment of structural changes occurring in keratoconus eyes. These changes were correlated with clinical and paraclinical characteristics of patients. The established classification not only allows structural follow-up of patients with keratoconus but also provides insight into the pathogenesis of keratoconus and treatment strategies for future research. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Background To evaluate the incidence, evolution, clinical characteristics, possible risk factors or preventive factors, and visual outcomes of epiretinal membrane (ERM) recurrence. Methods Retrospective study of 440 consecutive patients (440 eyes) who underwent pars plana vitrectomy for ERM. The internal limiting membrane (ILM) was peeled in 266 cases, with the help of indocyanine green in 27 cases and brilliant blue in 45 cases. Cases of symptomatic ERM recurrence were reoperated. Results The incidence of ERM recurrence was 5% (22/440), and 2% of the patients were reoperated (9/440). Epiretinal membrane recurrence was symptomatic in 9 cases (41%) and asymptomatic in 13 cases (59%). ILM peeling was the only factor preventing ERM recurrence (adjusted odds ratio = 0.33, P = 0.026). The use of staining dyes did not prevent recurrence (adjusted odds ratio = 0.35, P = 0.338). In the case of ERM reproliferation, the absence of ILM peeling, the existence of ERM on the fellow eye, and poor visual acuity before surgery seemed to be associated with a high risk of symptomatic recurrence and reoperation. The mean duration for follow-up was 3.5 ± 1.7 years. Conclusion ILM peeling not only reduces the likelihood of reproliferation of ERM but also seems to improve the visual prognosis of recurrent ERMs. The use of dyes did not reduce the rate of recurrence compared with when ILM was peeled without dyes.

A 48-year-old woman with no significant past history underwent bilateral simultaneous laser in situ keratomileusis for correction of her myopia. On the tenth postoperative day, the patient complained of visual decrease and photophobia. Slit lamp exam showed corneal epithelial irregularities. Confocal microscopy was performed and revealed a characteristic appearance of epithelial basement membrane dystrophy (EBMD). The patient was successfully treated with artificial tears and autologous serum eyedrops. EBMD may be missed before LASIK surgery, even after a careful pre-operative examination. Exacerbation of EBMD after LASIK surgery is rare. It should be considered when unexplained corneal epithelial defects or irregularities occur following LASIK. Confocal microscopy is very useful to confirm the diagnosis.

PURPOSE To assess the influence of donor characteristics on the outcome of anterior lamellar keratoplasty (ALK) and to evaluate whether corneal donor tissue considered unsuitable for penetrating or posterior lamellar keratoplasty due to poor endothelial condition may be safely used for ALK. METHODS Institutional setting. One hundred sixty-six consecutive ALK (166 patients) performed for optical indication in eyes with corneal diseases not involving the corneal endothelium. The main outcome measures were graft survival, early (0-12 months postoperatively) and late (after 12 months) annual endothelial cell loss, and postoperative logarithm of the minimum angle of resolution visual acuity. RESULTS The average and extreme values of donor tissue characteristics were: donor age, 70.6 years (range, 28-88 years); organ culture time, 20.9 days (range, 12-35 days); graft endothelial cell density before transplantation, 2047 cells per millimeters (range, 100-3300 cells/mm2); and deswelling time, 2.0 days (range, 1-4 days). The average follow-up time of patients was 48.1 ± 24.8 months (mean ± SD). None of the donor characteristics significantly influenced graft survival or postoperative endothelial cell loss (early and late phase). Donor age >80 years was associated with lower postoperative visual acuity at all postoperative points in time (P < 0.05). At 3 years, the mean logarithm of the minimum angle of resolution visual acuity was 0.44 (20/55) for grafts from donors older than 80 years and 0.25 (20/35) for younger donors. This result was shown to be significant both in univariate and in multivariate analysis. CONCLUSIONS Grafts from elderly donors should be discarded before ALK. Conversely, donor tissue with poor endothelial cell density (

Release of lead from 80% partially replaced service lines was compared to full lead service lines using harvested-stabilized lead pipes and field brass connectors. After more than a year of stabilization, lead release was consistent with field samples. Over the relatively short duration partial replacement of lead pipe by copper pipe (3 months), generated high lead release, attributed to galvanic corrosion, resulting in a final outcome for lead release that was even worse than for a full lead pipe. Increased lead release was especially evident at higher flow rates. Orthophosphate reduced lead release from full lead pipes by 64%. For partially replaced samples with copper, lead concentrations were unchanged by phosphate dosing at moderate flow (103 ± 265 vs 169 ± 349 μg/L) and were increased to very high levels when sampled at high flow rates (1001 ± 1808 vs 257 ± 224 μg/L). The increase lead release was in the form of particulate lead (>90%). In comparison to the condition without treatment, increased sulfate treatment had little impact on lead release from 100%-Pb rigs but reduced lead release from partially replaced lead pipes with copper. Our results also raise questions concerning protocols based on short 30 min stagnation (as those used in Canada) due to their incapacity to consider particulate lead release generated mostly after longer stagnation.