Conjunctivitis as a sign of persistent SARS-COV-2 infection? An observational study and report of late symptoms.

PURPOSE: To investigate if symptomatic conjunctivitis during the recovery phase of the disease could be associated to a persistent presence of SARS-CoV-2 in the upper respiratory tract. Secondary end points were to analyze the presence of SARS-CoV-2 in the conjunctiva of ocular symptomatic patients and to record the presence of ocular disturbances at this point of the disease. METHODS: An observational study including consecutive COVID19 patients treated at Humanitas Clinical and Research Hospital who were attending for nasopharyngeal swab to confirm the resolution of SARS-CoV-2 infection and end of isolation. We examined 129 consecutive patients from May to June 2020. The primary end point was to determine if symptomatic conjunctivitis at this point of the disease could be associated to a persistent presence of SARS-CoV-2 in the upper respiratory tract. Secondary end points were to analyze the presence of SARS-CoV-2 in the conjunctiva of ocular symptomatic patients and to record the presence of ocular disturbances at this point of the disease. RESULTS: One hundred twenty eight patients were included, 9.38% had conjunctivitis, none resulted positive to conjunctival PCR swab test, while two of them had positive nasopharyngeal result. Mean time elapsed since the first COVID-19 positive swab to the time of examination was 6 weeks ( ± 3). The only significant association was the presence of conjunctivitis with older age (65.3 ± 12.7 vs 56.7 + 13.5. p = 0.046). Nasopharyngeal swab resulted positive in 22 patients (17.19%). While 88 patients (68.2%) did not have any ocular complain during their COVID19 disease. The 40 patients (31.8%) reporting ocular disturbances complained about: redness (25.43%), tearing (19.53%), burning (18.35%), foreign body sensation (17.18%), itching (15.62%), and discharge (12.5%). CONCLUSION: This study showed that late conjunctivitis cannot be considered as a marker of persistent infection when patients are sent to confirm the resolution of SARS-CoV-2 infection.

Late Onset Descemet Membrane Detachment after Radial Keratotomy Resolved with Medical Therapy.

PURPOSE: To report a case of a Descemet membrane's (DM) detachment after radial keratotomy (RK). METHODS: A patient (male) underwent RK (16 cuts) 20 years before referring to the Eye Center of Humanitas (Milan) for a progressive visual loss. The slit-lamp examination showed severe corneal stromal edema and a large DM detachment in the lower half of the cornea. Anterior segment optical coherence tomography (AS-OCT) and endothelial cells count confirmed DM detachment and endothelial cells damage. Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) was planned and topical hypertonic therapy was prescribed before the surgery. RESULTS: Eight months later, the patient mentioned a spontaneous increase in visual acuity; the slit-lamp examination and the AS-OCT displayed a recovery of corneal transparency with a resolution of DM detachment. CONCLUSIONS: This is the first report of spontaneous DM detachment with severe corneal edema after RK. We suggest that hypertonic therapy may reduce DM detachment and restore corneal transparency.

Role of inflammation in endophthalmitis.

Inflammation originating from infection of the vitreous cavity is called endophthalmitis. Attention has been focused on the epidemiologic, microbiologic reports, and treatment options; unfortunately, the role of the host immune reaction in the visual function damage is still not well understood. Endophthalmitis occurs most frequently after cataract surgery. In this paper we review the published literature regarding inflammatory mediators and apoptosis during the course of endophthalmitis. Toll-like receptors, cytokines, high-mobility group box 1 proteins, aB-crystallin and apoptosis have been studied during clinical and experimental cases of endophthalmitis. Further understanding of the host-immune reaction to vitreous infection is essential for the development of new therapies. The use of intravitreal antibiotics and corticosteroids, vitrectomy and systemic antibiotics for the preservation of visual function is still discouraging.

Vitreo-papillary adhesion as a prognostic factor in pseudo- and lamellar macular holes.

PURPOSE: To determine the incidence of vitreopapillary adhesion (VPA) and to investigate its value as a prognostic factor in the surgical outcome of pseudo- (PMH) and lamellar macular holes (LMH). METHODS: A total of 76 consecutive patients, diagnosed with PMH (41 eyes) or LMH (35 eyes) were included. Eyes with VPA were alternatively assigned to the surgical or control group. Surgery consisted of a 25G vitrectomy and internal limiting membrane peeling with blue dye staining. There were six visits: baseline, the day of surgery, and 1, 3, 6, and 9 post-operative months. Main outcome measures were the incidence of VPA and changes in the outer retinal layers and visual acuity. RESULTS: VPA was found in 27% (11/41) of patients with PMH and 37% (13/35) with LMH (P=0.03). In presence of VPA, the best-corrected visual acuity (BCVA) improved in the surgery group from 32 ± 8 to 47 ± 8 letters, whereas the control group went from 34 ± 7 to 31 ± 8 letters. The difference in letters between the surgery and control groups was statistically significant for both distance (P=0.032) and near (P=0.04) vision. Intra-retinal cysts were significantly correlated with a poor functional prognosis (P=0.01). We found the presence of focal damage to the outer retinal layers in LMH and PMH. CONCLUSION: VPA is more frequent in the presence of LMH vsPMH. It significantly influences the tangential forces at the vitreoretinal interface, exacerbating anatomical changes, and worsening the functional prognosis. Functional difference between the surgical and control groups was statistically significant for distant and near vision in presence of VPA.

The yeast hnRNP-Like proteins Yra1p and Yra2p participate in mRNA export through interaction with Mex67p.

Yra1p is an essential nuclear protein which belongs to the evolutionarily conserved REF (RNA and export factor binding proteins) family of hnRNP-like proteins. Yra1p contributes to mRNA export in vivo and directly interacts with RNA and the shuttling mRNP export receptor Mex67p in vitro. Here we describe a second nonessential Saccharomyces cerevisiae family member, called Yra2p, which is able to complement a YRA1 deletion when overexpressed. Like other REF proteins, Yra1p and Yra2p consist of two highly conserved N- and C-terminal boxes and a central RNP-like RNA-binding domain (RBD). These conserved regions are separated by two more variable regions, N-vr and C-vr. Surprisingly, the deletion of a single conserved box or the deletion of the RBD in Yra1p does not affect viability. Consistently, neither the conserved N and C boxes nor the RBD is required for Mex67p and RNA binding in vitro. Instead, the N-vr and C-vr regions both interact with Mex67p and RNA. We further show that Yra1 deletion mutants which poorly interact with Mex67p in vitro affect the association of Mex67p with mRNP complexes in vivo and are paralleled by poly(A)(+) RNA export defects. These observations support the idea that Yra1p promotes mRNA export by facilitating the recruitment of Mex67p to the mRNP.

Prevention of corneal ectasia in laser in situ keratomileusis.

PURPOSE: Ectasia after laser in situ keratomileusis (LASIK) is a rare but serious complication. Prevention includes proper patient selection with detection of those at particular risk. Causes of ectasia include predisposition, excessive ablation with less than 250 microm of residual stromal bed, thicker than normal flap, irregular corneal thickness, and different ablation rates. METHODS: We evaluated corneal curvature patterns and their relationship to corneal topography and pachymetry maps. RESULTS: Corneal topography (axial, tangential, and altimetric) and pachymetry map characteristics of normally astigmatic corneas, keratoconus, false-positive and false-negative cases, as well as contact lens-induced warpage are discussed. CONCLUSIONS: Preoperative pachymetry maps for LASIK surgery allow accurate case selection through detection of borderline cases, and provide important documentation of preoperative status, as well as useful information for improving surgical strategy. Another important parameter is the asphericity index.

Decentration after refractive surgery.

PURPOSE: To examine factors useful in evaluation of suspect decentration after refractive surgery. METHODS: We evaluated 148 cases (eyes) referred to us for recentering procedures by review of information obtainable by evaluation of pupil position, corneal topography, and corneal curvature gradient. RESULTS: Only a minority of eyes (n=5, 3.4%) were truly decentered; in the remaining majority a high dioptric gradient with consequent focal scarring was present (n=107, 72.3%). In 28 eyes (18.9%), a drifting of the eye during treatment was responsible, and in eight eyes (5.4%), a central island was observed. CONCLUSIONS: Proper corneal topographical diagnosis reduces the risk of improperly suspecting decentration, and for most cases, smoothing of the central cornea is a simple and efficacious solution. Recommendations for the prevention of decentration include proper patient positioning, special care in treating high myopes, preoperative check of pupil displacement nasally, evaluation of preoperative map with detection of high temporal curvature gradient, and use of the cross-cylinder technique in the treatment of astigmatism.

Photorefractive keratectomy to correct myopic or hyperopic astigmatism with a cross-cylinder ablation.

PURPOSE: To assess the efficacy and safety of a combined ablation of the steep and flat meridian to correct astigmatism with the excimer laser. METHODS: Twenty-two eyes with myopic, mixed, or hyperopic astigmatism (mean preoperative spherical equivalent refraction -4.30 +/- 4.70 D [range, -12.50 to +1.50 D] and mean preoperative cylinder magnitude -3.40 +/- 1.40 D [range, -1.50 to -6.00 D]) underwent PRK with the Nidek EC-5000 excimer laser. The surgical strategy involved ablating half the amount of the cylinder (in diopters) along steepest meridian, the other half in a subsequent step along the flattest meridian; thereafter, the spherical equivalent was corrected. RESULTS: Six months postoperatively, mean spherical equivalent refraction was -0.07 +/- 0.87 D and mean cylinder was -0.44 +/- 0.36 D. Mean spectacle-corrected visual acuity was 0.86 +/- 0.13 compared to 0.75 +/- 0.22 preoperatively. Mean corneal haze was 0.67 +/- 0.31. No patient lost 2 or more lines of spectacle-corrected visual acuity and there were no complaints about night halos or glare. CONCLUSIONS: Unlike other ablation strategies, the cross-cylinder method creates a smooth transition (low dioptric gradient) between the treated and untreated cornea. This is achieved by first treating the cylinder and making the corneal surface spherical and then ablating the spherical component of the refractive error.

Algorithm to correct hyperopic astigmatism with the Nidek EC-5000 excimer laser.

BACKGROUND: The efficacy of a new ablation algorithm for the correction of hyperopic astigmatism with the Nidek EC-5000 excimer laser was evaluated. METHODS: Twenty-five eyes with mean preoperative hyperopia of +3.76 +/- 1.70 D and a mean hyperopic cylinder of 2.20 +/- 0.80 D underwent photorefractive keratectomy (PRK) using a new algorithm with the Nidek EC-5000 excimer laser (software version 3.0). The new algorithm differed from previous algorithms in that less tissue was removed for the same amount of diopters, and there was less of a dioptric gradient between the optical zone and the transition zone. Mean preoperative spectacle-corrected visual acuity was 0.8 +/- 0.09. Minimum follow-up was 6 months. RESULTS: Mean postoperative spectacle corrected visual acuity (geometric mean) increased significantly to 0.89 +/- 0.1. The mean sphere decreased by 3.08 D and the mean cylinder by 1.60 D. CONCLUSION: Hyperopic PRK using the Nidek EC-5000 excimer laser with this new algorithm for hyperopic astigmatism appears to be safe and effective.

Zonal photorefractive keratectomy for presbyopia.

PURPOSE: We performed zonal excimer laser photorefractive keratectomy in three eyes of three presbyopic patients using a specially designed mask, with a minimum follow-up of 24-months. METHODS: Two females (ages 59 and 48) and one male (age 55) were included in the study. The procedure was performed with a mask designed by one of the authors (GMN), applied to the Aesculap-Meditec Mel 60 excimer laser. The mask consists of a mobile diaphragm formed by two blunt blades. The aim in all the eyes was a presbyopic correction of 3.00 D. RESULTS: After an initial regression of 1.00 D, the presbyopic correction remained stable during the 36-month follow-up. The patients read at least J3 at normal reading distance without correction. Since the ablated zone was only about 15% of the total area of a 3.0 mm pupil, all three patients were also able to read with their preoperative presbyopic correction (using the untreated 85% of the pupillary area). CONCLUSION: Although only three eyes were treated with the zonal presbyopia mask presented here, the visual and refractive outcome appears promising in view of the relatively long follow-up time.

Long-term results of photorefractive keratectomy for hyperopia and hyperopic astigmatism.

PURPOSE: This study was conducted to determine the safety and efficacy of using the Nidek EC-5000 excimer laser for photorefractive keratectomy to correct hyperopia and hyperopic astigmatism. METHODS: We treated 67 eyes of 44 patients for hyperopia and hyperopic astigmatism with the Nidek EC-5000 excimer laser. The algorithm provided an ablation zone of 5.5 mm diameter with the addition of a tapered transition zone of 3.5 mm diameter, for a total ablation of 9 mm diameter. RESULTS: Uncorrected visual acuity (geometrical mean) changed from 0.16 to 0.37 at 12 months; corrected visual acuity (geometrical mean) changed from 0.8 to 0.89; mean sphere decreased by 2.08 D from 3.76 to 1.40 D (range, 1.70 to 1.68 D) and cylinder by 1.40 D from 2.20 to 1.00 D. Refractive results for < or = 3.00 D were reasonably accurate and stable, but for > +3.00 D, undercorrection and regression over l year were the rule. CONCLUSION: Hyperopic PRK proved to be a safe technique in regard to the risk of loss of visual acuity with no central corneal opacities and with a generally rapid recovery of baseline spectacle-corrected visual acuity, but the predictability of correction greater than +3.00 needs improvement.

Effect of decreasing surface and interface irregularities after photorefractive keratectomy and laser in situ keratomileusis on optical and functional outcomes.

PURPOSE: To assess a new method for decreasing corneal ablated surface irregularities after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) by performing a final smoothing immediately after the treatment. METHODS: One hundred forty-seven eyes with ablation irregularities after PRK or LASIK using the Nidek ED-5000 excimer laser and examined with the Nidek EAS 1000, were randomized into two groups: 74 eyes had final smoothing and 73 eyes were patched immediately. Preoperative mean refraction for the smoothing group was -7.55 +/- 2.50 D and for the patched group, it was -7.30 +/- 1.90 D, (p = 0.04). RESULTS: AT 12 months after treatment, mean haze was 0.5 +/- 0.3 in the smoothing group and 1.2 +/- 0.4 in the patched group (p = 0.006); mean spectacle-corrected visual acuity was 1.1 +/- 0.25 in the smoothing group and 0.95 +/- 0.18 in the patched group (p = 0.02); the percentages of eyes within 1.00 D of the planned correction was 68% in the smoothing group and 33% in the patched group. CONCLUSION: Performing a final smoothing immediately after PRK or LASIK improves refractive and optical outcomes.

A method for examining surface and interface irregularities after photorefractive keratectomy and laser in situ keratomileusis: predictor of optical and functional outcomes.

PURPOSE: To develop a system for the examination of the ablated surface after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) and to correlate the surface regularity to the functional outcome. METHODS: A Nidek Eas-1000 Anterior Eye Segment Analysis System was used to examine the ablated surface or the interface regularity immediately after PRK and LASIK. Eighty eyes were evaluated and divided into three study groups; group 1; regularity (18 eyes), group 2; mild irregularity (32 eyes) group 3; severe irregularity (30 eyes). RESULTS: At 12 months postoperatively, group 1 (regularity) showed the best percentage of eyes with 0 haze (100%) and with a refraction +/- 1.00 D of plano (89%); group 2 (mild irregularity) 84% had 0 haze and 62% were +/- 1.00 D of plano; group 3 (severe irregularity) 27% had 0 haze and 47% were +/- 1.00 D of plano. CONCLUSION: The patients with no postoperative irregularity had a sharply lower incidence of haze and a better refractive outcome with respect to plano, confirming the influence of ablation regularity on the results and the importance of this analysis in clinical practice.

Excimer laser photorefractive keratectomy for presbyopia: 24-month follow-up in three eyes.

BACKGROUND: For some patients, standard optical correction for presbyopia is not satisfactory. Using a specially designed mask, we developed a procedure for correcting presbyopia with excimer laser photorefractive keratectomy (PRK). METHODS: A mask consisting of a mobile diaphragm formed by two blunt blades was used to ablate a 10 to 17 microm deep semilunar-shaped zone immediately below the pupillary center, steepening the corneal curvature in that area. Three eyes of three presbyopic patients were treated, aiming at a near addition of +3.00 D. Follow-up time was 24 months. RESULTS: After an initial regression of 1.00 D during the first 6 months, the presbyopic correction remained stable for the duration of the follow-up period, enabling uncorrected near vision of J3 in all three eyes. Uncorrected distance visual acuity was not altered. Contrast sensitivity (Regan) was slightly decreased only at the 11% level. Videokeratography confirmed corneal steepening in the ablated area. CONCLUSION: The visual and refractive outcome of excimer laser PRK for presbyopia with the Aesculap-Meditec MEL 60 is promising, especially in view of the 2-year follow-up.

Radial and staggered treatment patterns to correct hyperopia using noncontact holmium:YAG laser thermal keratoplasty.

PURPOSE: To compare the effects of two treatment patterns in the correction of hyperopia by noncontact holmium:YAG laser thermal keratoplasty (LTK). SETTING: Divisione Oculistica, Ospedale S. Gerardo, Monza, Italy. METHODS: Using two treatment patterns, we performed noncontact LTK in one session in 16 eyes of 8 patients with isometropic hyperopic refractive errors; mean preoperative subjective cycloplegic refraction was +4.90 diopters (D) +/- 1.17 (SD). The treatment consisted of 24 spots in three concentric rings of eight spots each; ring diameters were 6.0, 7.0, and 8.0 mm, respectively. Each spot received seven pulses of laser energy at 30 mJ/pulse. We treated one eye of each patient with a radial pattern (the spots of the three rings aligned on the eight semimeridians) and the fellow eye with a staggered pattern (the spots of the contiguous rings at 22.5 degrees from each other). Follow-up at 1, 15, 30, 90, 180, and 360 days included subjective cycloplegic refraction, uncorrected (UCVA) and spectacle-corrected visual acuity (SCVA), computerized videokeratography (CVK), and Scheimpflug camera examination. RESULTS: One year postoperatively, the mean subjective cycloplegic refraction was +2.75 +/- 1.6 D in the eyes treated with the radial pattern and +3.40 +/- 1.6 D in those treated with the staggered pattern; the mean change in subjective cycloplegic refraction was 2.15 and 1.50 D, respectively. Mean UCVA improved by five lines in the radial group and by four lines in the staggered group. Mean SCVA returned to preoperative levels by day 15 in the radial group and at 1 year in the staggered group; at 1 year, SCVA improved by one line in the radial group and remained unchanged in the staggered group. No eye lost one or more lines of SCVA. Refractive astigmatism was essentially unchanged in both groups. Scheimpflug photography and CVK indicated larger and more uniform corrected zones in the radial group. CONCLUSIONS: Radial and staggered patterns effectively corrected low hyperopia, although both were subject to a certain amount of regression. The radial pattern produced faster postoperative recovery of SCVA and demonstrated greater refractive stability.