Investigation of Thiol/Disulfide Homeostasis and Clinical Parameters in Rosacea Patients According to Skin Subtypes.

Background/Objective: The aim of this study was to compare thiol/disulfide homeostasis and clinical parameters of rosacea patients across skin subtypes of the disease and healthy controls. Methods: This prospective study included 90 rosacea patients with different skin subtypes (phymatous, erythematotelangiectatic and papulopustular) and ocular involvement and 30 healthy controls. Plasma native thiol (NT), total thiol (TT) and disulfide levels of the patients and controls were measured using an automated spectrophotometric method, and disulfide/native thiol ratio (DNTR), disulfide/total thiol ratio (DTTR) and native thiol/total thiol ratio (NTTR) were calculated. Tear breakup time (TBUT), meiboscore, Schirmer, ocular surface disease index (OSDI) and rosacea-specific quality of life scale (RosaQoL) were measured clinically. Results: Disulfide, DNTR and DTTR were significantly higher, and NT, TT and NTTR were significantly lower in the rosacea patients compared to the controls (p < 0.001). TBUT and Schirmer were significantly lower, and meiboscore and OSDI were significantly higher in the patients compared to the controls (p < 0.01). According to the skin subtypes, disulfide, DNTR and DTTR were significantly higher, and NTTR was significantly lower in the erythematotelangiectatic subtype compared to the other subtypes (p < 0.002). TBUT was significantly lower, and RosaQol was significantly higher in the erythematotelangiectatic subtype (p < 0.0083). Strong correlations were found between DNTR and TBUT and between DNTR and Meiboscore in all subtypes (p < 0.005), while there were strong correlations between DNTR and OSDI and between DNTR and RosaQol only in the erythematotelangiectatic and papulopustular subtypes (p < 0.05). Conclusions: The thiol/disulfide homeostasis shifted towards disulfides, an indicator of oxidative stress in rosacea, and this was more pronounced in the erythematotelangiectatic subtype. The impairment in TBUT and RosaQol was also more prominent in the erythematotelangiectatic subtype and strongly associated with the DNTR.

Investigation of Choroidal Thickness and Choroidal Vascularity Index in Ocular Rosacea Patients According to Skin Subtypes.

BACKGROUND: To compare the choroidal thickness (CT) and choroidal vascularity index (CVI) values in ocular rosacea (OR) patients across skin subtypes of the disease and healthy controls. METHODS: This prospective study included 90 eyes of 90 mild-moderate OR patients with different skin subtypes (30 phymatous, 30 papulopustular and 30 erythematotelangiectatic) and 30 eyes of 30 age-gender matched healthy volunteers. After obtaining the enhanced depth imaging optical coherence tomography images, the CT was measured at subfoveal, 1500µm nasal and 1500µm temporal to the fovea, and the CVI was calculated using Image J software in the subfoveal, nasal and temporal areas. RESULTS: There was no CT significant difference between OR patients and healthy controls in all regions (p>0.05). CVI values of OR patients were found to be significantly lower in the subfoveal, nasal and temporal regions compared to healthy controls (p=0.02, p=0.01, p=0.01, respectively). No CT difference was detected between the subtypes and healthy controls in all regions (p>0.05). Subfoveal-CVI was significantly lower in the phymatous subtype than the other subtypes and controls (p<0.05), while nasal and temporal-CVI were significantly lower in the phymatous and papulopustular subtypes than the erythematotelangiectatic subtype and controls. CONCLUSION: Our study demonstrated no difference between rosacea skin types and healthy controls in terms of CT. Phymatous and papulopustular subtypes were more likely to be affected by chronic inflammation with having lower CVI in most of the regions. Further studies are needed to investigate the association of inflammatory factors with CVI in OR.

Comparison of Corneal Biomechanical Efficacy Between Rose Bengal-Green Light and Riboflavin-UVA Crosslinking.

PURPOSE: To investigate corneal biomechanical changes after corneal cross-linking (CXL) treatments with rose bengal-green light (RB-CXL) and riboflavin-UVA (RF-CXL). METHODS: A total of 60 freshly enucleated lamb eyes were obtained for this experimental study. Fifteen eyes were treated with RB-CXL using 0.1% RB solution (Group 1), 15 eyes were treated with RB-CXL using 0.2% RB solution (Group 2), 15 eyes were treated with RF-CXL using 0.1% RF solution (Group 3), and 15 eyes were used as controls (Group 4). The same treatment protocol (10-minute irradiation using a total of 5.4 J/cm2 energy) was applied to all treatment groups. To evaluate corneal biomechanical changes, the stress-strain test was used for both the treated and control corneas. The elastic modulus was calculated using the tension strain curves obtained during the test. RESULTS: The average elastic modulus values were calculated to be 18.9, 23.5, 22.3, and 14.1 MPa in Groups 1, 2, 3, and 4, respectively. Statistically significant differences were found between the groups (p < 0.001 for Group 1 vs. 2; p < 0.001 for Group 1 vs. 3; p < 0.001 for Group 1 vs. 4; p = 0.002 for Group 2 vs. 3; p < 0.001 for Group 2 vs. 4; and p < 0.001 for Group 3 vs. 4). CONCLUSIONS: In this study, the efficacy of RB-CXL treatment applied using different concentrations of RB solutions at a total energy of 5.4 J/cm2 was investigated, and 0.2% RB solution was found to have at least as much and even more effective than the RF-CXL (0.1% RF) on the corneal elasticity module. These results are encouraging for the treatment of ectatic corneas particularly below 400 µm. It is considered that the findings obtained from this study will guide future experimental and clinical studies.

Evaluation of Ocular and Systemic Oxidative Stress Markers in Ocular Rosacea Patients.

Purpose: To investigate oxidative stress markers in tears and serum of patients with ocular rosacea and to examine their association with both ocular surface parameters and cutaneous rosacea subtypes. Methods: This prospective study includes rosacea patients with ocular involvement and healthy controls. We performed ophthalmological examination of all participants and collected tear breakup time (TBUT), Schirmer, Meibomian gland dysfunction (MGD) and Ocular Surface Disease Index (OSDI) scores. We quantified the total antioxidant status (TAS), total oxidant status (TOS), and arylesterase (ARE) levels from tear and serum samples, and calculated the oxidative stress index (OSI). We also classified patients into phymatous, erythematotelangiectatic, papulopustular subtypes. Results: We included 90 ocular rosacea patients and 30 healthy controls. Oxidative stress (TOS, OSI) levels were significantly higher (P < 0.01) and antioxidant levels (TAS, ARE) were significantly lower (P < 0.01) in both tear and serum samples of ocular rosacea patients as compared to controls. We found a significant positive correlation between the tear and serum values regarding oxidative stress parameters (P < 0.05). Besides, OSI was negatively correlated with TBUT and positively correlated with MGD score (meiboscore) and OSDI (P < 0.05). The Schirmer score was not correlated with OSI. No difference was found between the cutaneous subtypes with respect to TAS, TOS, ARE, and OSI results. Conclusions: In this study, we identified oxidative stress markers in the serum and tears of ocular rosacea patients and showed their correlation with clinical signs of MGD, suggesting that oxidative stress contributes to ocular rosacea pathogenesis and that oxidative stress could be an indicator of MGD severity.

Comparison of Hybrid Contact Lenses and Rigid Gas-Permeable Contact Lenses in Moderate and Advanced Keratoconus.

Objectives: We aimed to compare the clinical results and topographic data of the new generation hybrid contact lens (HCL) and rigid gas-permeable contact lens (RGPCL) in patients with moderate and advanced keratoconus. Materials and Methods: In this prospective study, HCL users comprised group 1 and RGPCL users comprised group 2. Snellen uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), and lens-corrected visual acuity (LCVA); manifest spherical-cylindrical values; corneal topography measurements (flat keratometry [K1], vertical keratometry [K2], mean K, maximum K [Kmax], central corneal thickness [CCT], and thinnest corneal thickness [TCT]); and cone location were recorded. Results: The study included 83 eyes of 51 patients in group 1 and 61 eyes of 40 patients in group 2. The groups were similar in age and gender (p>0.05). Mean LCVA (logMAR) was significantly lower than BCVA in both groups (p<0.001). The mean visual gain with contact lenses (Snellen chart) was 3.4±1.8 lines in group 1 and 4.0±2.1 lines in group 2. There was no significant difference between the two groups in BCVA, LCVA, or lines gained (p>0.05). There was also no significant difference between the two groups in terms of keratoconus stages, mean Kmax, CCT, TCT, or cone location (p>0.05), while mean UCVA (logMAR) and mean K were higher in group 2 (p<0.05). In both groups, the visual gain with lenses was higher in eyes with central cones, and there was significantly greater visual increase in group 2 (p=0.039). Conclusion: In moderate and advanced keratoconus, HCLs improved vision as much as RGPCLs and both lenses were more effective for central cones. Nevertheless, longer term of follow-up and larger numbers of patients are needed for long term follow-up results of HCL.

Toll-like receptor-4 expression and oxidative stress in ocular rosacea.

Purpose: To investigate systemic and ocular toll-like receptor (TLR)-4 expression and its association with oxidative stress markers in ocular rosacea (OR). Methods: This prospective study included 40 patients with rosacea with ocular involvement and 20 healthy volunteers. Tear break-up time (TBUT), Schirmer test, meibomoscore, and ocular surface disease index (OSDI) scores were estimated for all participants. TLR-4 expression in conjunctival epithelium and peripheral blood mononuclear cells was quantified using real-time polymerase chain reaction (RT-PCR). In the tears and serum samples of all participants, antioxidant status (TAS), total oxidant status (TOS), and arylesterase (ARE) activation levels were measured using a fully automated spectrophotometric method, and the oxidative stress index (OSI) was calculated. Results: TLR-4 expression levels and oxidative stress status (TOS and OSI values) were significantly higher (p < 0.01), and antioxidant status (TAS and ARE values) were significantly lower (p < 0.01) in both ocular and blood samples of patients with OR compared with those in controls. A significant positive correlation was found between the ocular and blood values in all parameters (p < 0.05). According to the clinical associations of these results, we found negative correlations between TLR-4, OSI, and TBUT and between TLR-4 and Schirmer, whereas a positive correlation was observed between TLR-4, OSI, and meiboscore and between TLR-4, OSI, and OSDI (p < 0.05). No correlation was found between the OSI and Schirmer results (p = 0.92). Conclusions: TLR-4 and oxidative stress both play important roles in OR pathophysiology and are closely related to clinical findings.

Aquaporin-4 protein antibody-associated optic neuritis related to neuroendocrine tumor after receiving an inactive COVID-19 vaccine.

Neuromyelitis optica (NMO), also known as Devic's disease, is a rare, autoimmune, and recurrent demyelinating disorder that primarily affects the spinal cord and optic nerve. We report a case with recurrent optic neuritis caused by the paraneoplastic NMO spectrum disorder in the setting of a gastric neuroendocrine tumor 2 weeks after receiving an inactive COVID-19 vaccine.

36-Month Outcomes of Mechanical and Transepithelial PTK Epithelium Removal Techniques Prior to Accelerated CXL for Progressive Keratoconus.

PURPOSE: To compare the 36-month visual, refractive, and topographic results and the optical quality of the cornea between mechanical and transepithelial phototherapeutic keratectomy (PTK) epithelium removal techniques prior to the accelerated corneal cross-linking (CXL) procedure in patients with progressive keratoconus. METHODS: Keratoconic eyes that received either mechanical epithelium removal or transepithelial PTK epithelium removal prior to accelerated CXL with 36 months of follow-up were included. The uncorrected (UDVA) and corrected (CDVA) distance visual acuity, spherical equivalent (SE), manifest astigmatism, flat keratometry (K1), steep keratometry (K2), maximum keratometry (Kmax) readings, thinnest corneal thickness (TCT), topographic astigmatism, point spread function (PSF), and aberrometric parameters including root mean square higher order aberrations (RMS HOAs), vertical coma, and spherical aberration (SA) were assessed preoperatively and 12, 24, and 36 months postoperatively. RESULTS: One hundred ten eyes of 110 patients with keratoconus were included (mechanical epithelium removal group: 69 eyes, transepithelial PTK epithelium removal group: 41 eyes). After the CXL procedure, the mean UDVA, CDVA, manifest astigmatism, RMS HOAs, SA, vertical coma, and PSF improved significantly throughout the follow-up visits in both groups (P < .05 for all variables). The improvement in the mean UDVA, CDVA, manifest astigmatism, K1, K2, Kmax, RMS HOAs, SA, vertical coma, and PSF were significantly better in eyes that underwent transepithelial PTK epithelium removal when compared to eyes that underwent mechanical epithelium removal during the follow-up period (P < .05 for all variables). CONCLUSIONS: Transepithelial PTK-assisted accelerated CXL seems to be more efficient in improving the visual acuity and the optical quality while stabilizing the cornea compared to the accelerated CXL with mechanical epithelium removal in patients with progressive keratoconus. [J Refract Surg. 2022;38(3):191-200.].

Dynamics of keratoconus progression after a previous successful accelerated crosslinking treatment during and after pregnancy.

PURPOSE: To evaluate the effectiveness of previously applied successful accelerated corneal crosslinking (CXL) treatment in keratoconus stabilization during and after pregnancy. SETTING: Ankara Yildirim Beyazit University, Ataturk Training and Research Hospital, Turkey. DESIGN: Prospective clinical study. METHODS: Patients with stable keratoconus (after having an accelerated CXL procedure) who became pregnant were included. Uncorrected (UDVA) and corrected distance visual acuity (CDVA), manifest astigmatism (MA), keratometry (K)1, K2, Kmax, central corneal thickness (CCT), thinnest corneal thickness (TCT), and anterior (AE) and posterior elevation (PE) were recorded at baseline (before CXL), before pregnancy (the last visit after CXL), during pregnancy (third trimester), and after pregnancy (the last visit after pregnancy). RESULTS: 24 eyes of 19 patients were included. The mean time between CXL and conception was 12.4 ± 5.1 months. The mean postpartum follow-up period was 27.6 ± 13.3 months. The mean UDVA, CDVA, MA, and PE values did not show any statistically significant differences during and after pregnancy compared with the post-CXL values (P > .05). The mean Kmax flattened significantly after the CXL procedure (P = .011); however, it increased during pregnancy (P = .037, after CXL vs pregnancy) and then decreased back to the prepregnancy level after pregnancy (P = .035, pregnancy vs after pregnancy). The mean K1, K2, AE, CCT, and TCT remained stable during pregnancy and significantly decreased after pregnancy (P < .05). CONCLUSIONS: Keratoconus seems to progress during pregnancy in corneas that have previously received successful accelerated CXL treatment. However, this progress was mostly temporary, and generally, regression occurred after delivery.

CENTRAL SEROUS CHORIORETINOPATHY: High-Resolution Imaging of Asymptomatic Fellow Eyes Using Adaptive Optics Scanning Laser Ophthalmoscopy.

PURPOSE: To investigate cone density in the asymptomatic fellow eye of patients with unilateral central serous chorioretinopathy (CSCR). METHODS: Seventeen asymptomatic fellow eyes of patients with unilateral CSCR and 17 eyes of aged-matched and gender-matched healthy controls underwent adaptive optics ophthalmoscopy. Cone density and spacing were assessed at the fovea. Clinical and multimodal imaging findings were also recorded. RESULTS: In the CSCR group, the patient mean age was 48.9 ± 9.8 years. The mean (±SD) subfoveal choroidal thickness was 417.8 ± 125.2 µm. The foveal external limiting membrane and ellipsoid zone were intact in all patients. Adaptive optics fundus imaging showed a significant decrease in cone density at 2° of eccentricity nasal and temporal to the fovea in asymptomatic fellow eyes of patients with unilateral CSCR compared with controls (P = 0.001 and P = 0.027, respectively). No statistically significant difference in cone density was found at 4° of eccentricity nasal and temporal to the fovea between both groups. CONCLUSION: Asymptomatic fellow eyes of patients with unilateral CSCR showed a reduced density of foveal cones in the absence of a decreased visual acuity and photoreceptor line disruption on optical coherence tomography. These results suggest that the photoreceptors could be damaged independently of the occurrence of a serous retinal detachment.

Comparison of effects of mydriatic drops (1% cyclopentolate and 0.5% tropicamide) on anterior segment parameters.

Purpose: The purpose of this study is to investigate and compare the effects of cyclopentolate and tropicamide drops on anterior segment parameters in healthy individuals. Methods: Two hundred and fifty-eight eyes of 129 healthy volunteers were included in this randomized clinical study. Cyclopentolate 1% drop was applied to 75 (58%) participants (group 1) and tropicamide 0.5% drop was applied to 54 (42%) participants (group 2). Flat keratometry (K1), steep keratometry (K2), axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), white-to-white (WTW) distance, pupil diameter, total pupil offset and intraocular lens (IOL) power were measured before and after drops, using Lenstar 900 optical biometry. Results: The increase in CCT, ACD, pupil diameter, and pupil offset was significant in group 1 after the drop (P < 0.05), while the increase in ACD, pupil diameter, and pupil offset was significant in group 2 (P < 0.05). When the two groups were compared, there was no significant difference in K1, K2, CCT, ACD, WTW, pupil diameter, pupil offset, and IOL power (using Sanders-Retzlaff-Kraff T formula) changes after drops (P > 0.05), whereas the change in AL was significant (P = 0.01). Conclusion: The effects of cyclopentolate and tropicamide drops on anterior segment parameters were similar; they did not make significant changes in K1, K2, AL, WTW, and third-generation IOL power calculation. However, ACD values significantly changed after these drops; thus, measuring anterior segment parameters before mydriatic agents should be taken into account particularly for fourth-generation IOL formulas and phakic IOL implantation. The change in pupil offset, which can be important in excimer laser and multifocal IOL applications, was not clinically significant.

Cutaneous and ocular rosacea: Common and specific physiopathogenic mechanisms and study models.

Rosacea is a chronic inflammatory disease that affects the face skin. It is clinically classified into the following four subgroups depending on its location and severity: erythematotelangiectatic, papulopustular, phymatous, and ocular. Rosacea is a multifactorial disease triggered by favoring factors, the pathogenesis of which remains imperfectly understood. Recognized mechanisms include the innate immune system, with the implication of Toll-like receptors (TLRs) and cathelicidins; neurovascular deregulation involving vascular endothelial growth factor (VEGF), transient receptor potential (TRP) ion channels, and neuropeptides; and dysfunction of skin sebaceous glands and ocular meibomian glands. Microorganisms, genetic predisposition, corticosteroid treatment, and ultraviolet B (UVB) radiation are favoring factors. In this paper, we review the common and specific molecular mechanisms involved in the pathogenesis of cutaneous and ocular rosacea and discuss laboratory and clinical studies, as well as experimental models.

Outcomes of toric intraocular lens implantation after femtosecond laser and traditional cataract surgery.

CLINICAL RELEVANCE: Having an understanding of the refractive outcomes of different forms of cataract surgery will assist optometrists in explaining the implication of such procedures to patients being referred for such procedures. BACKGROUND: The purpose of this study was to compare the refractive outcomes after toric intraocular lens implantation between femtosecond laser-assisted cataract surgery and traditional phacoemulsification. METHODS: This retrospective non-randomised case series included 114 eyes of 92 consecutive patients (59 male and 55 female) aged 71.65 ± 10.46-years (range 57 to 92-years), who underwent either femtosecond laser-assisted cataract surgery (using two laser platforms) (group 1) or traditional phacoemulsification (group 2) between August 2013 and September 2015. Pre-operative keratometric values, the attempted refraction from the biometry platform and the toric intraocular lens web-based calculator, and the one month post-operative manifest refraction were assessed to evaluate the refractive outcomes of the two groups. RESULTS: Mean pre-operative topographic corneal astigmatism was -1.94 ± 0.73 D (range 0.91 to 4.61 D) and -1.98 ± 0.60 D (range 1.07 to 3.43 D) for groups 1 and 2, respectively (p > 0.05). Mean axial length was 24.22 ± 0.73-mm (range 21.78 to 29.30-mm) and 24.60 ± 1.09-mm (range 21.82 to 25.95-mm) for groups 1 and 2, respectively (p > 0.05). Multivariate vector analysis of the remaining refractive error between the two groups (desired refraction minus achieved refraction) revealed no statistically significant difference (p > 0.05). Analysis within each group demonstrated a higher accuracy of refractive outcomes for the femtosecond laser-assisted cataract surgery eyes (p < 0.05) when compared to the traditional phacoemulsification (p > 0.05). CONCLUSION: Femtosecond laser-assisted cataract surgery and traditional phacoemulsification demonstrate similar refractive outcomes after toric intraocular lens implantation, while femtosecond laser-assisted cataract surgery seems to provide a slightly higher accuracy.

Rose Bengal-Mediated Photodynamic Antimicrobial Treatment of Acanthamoeba Keratitis.

Purpose: To evaluate the in vivo efficacy of rose bengal (RB)-mediated photodynamic antimicrobial therapy (PDAT) for treatment of Acanthamoeba castellanii keratitis (AK). Materials and Methods: An animal (rabbit) AK model was successfully achieved via intrastromal inoculation of a suspension of A. castellanii cells and trophozoites. Prior to RB-PDAT (pre-treatment, day-5), the severity of the induced corneal infection was graded numerically for epithelial defects, stromal edema, neovascularity, and stromal opacity/infiltration. The right eyes of rabbits (n = 18) were divided equally into three groups (n = 6/group): control (no treatment); 0.1% RB+518 nm irradiation (5.4 J/cm2); and 0.2% RB+518 nm irradiation (5.4 J/cm2). On post-treatment day-5, animals were euthanized, after which corneal buttons were excised and submitted for real-time polymerase chain reaction (RT-PCR) analysis. Results: Post-treatment clinical scores of the 0.1 and 0.2% RB groups indicated significant improvement compared to control group scores (pre-treatment clinical scores; 5.17 ± 0.98, 7.50 ± 0.62, and 6.17 ± 0.70 and post-treatment clinical scores; 4.50 ± 0.56, (p = .043), 3.50 ± 0.99 (p = .039), 6.83 ± 1.66 (p = .34), respectively). RT-PCR analysis revealed that the mean cycle threshold (Ct) values were significantly higher in treated-group corneas compared to control-group corneas, with no significant differences between treated-groups (Mean Ct values; 34.33, 34.5, and 29.67 for 0.1 and 0.2% RB, and control groups). There was a statistically significant negative correlation between post-treatment clinical scores and Ct values (r = -0.474, p-value 0.047). Conclusions: Our results demonstrate that RB-PDAT is effective in decreasing the parasitic load and clinical severity of AK.

Comparison of Mix-and-Match Implanted Bifocal IOLs and Bilateral Implanted Trifocal IOLs After Femtosecond Laser-Assisted Cataract Surgery.

PURPOSE: To compare the visual performance of mix-and-match implanted bifocal intraocular lenses (IOLs) and bilateral implanted trifocal IOLs from the same manufacturer with the same IOL platform after femtosecond laser-assisted cataract surgery (FLACS). METHODS: This prospective, comparative, non-randomized study included patients who underwent FLACS (LenSx; Alcon Laboratories, Inc., Fort Worth, Texas) with bilateral implantation of bifocal IOLs (ReSTOR +2.50 D/+3.00 D; Alcon Laboratories, Inc.) or trifocal IOLs (PanOptix; Alcon Laboratories, Inc.). Visual acuities, manifest refraction, defocus curve, contrast sensitivity, quality of life measured by the Visual Function Index (VF-14), and spectacle independence were assessed at 6 months after surgery. RESULTS: A total of 70 eyes of 35 patients were included in this study. There was no difference in patient demographics and preoperative measurements between groups (P > .05). There was no difference in uncorrected distance visual acuity and corrected distance visual acuity outcomes between groups (P > .05), but uncorrected intermediate visual acuity and uncorrected near visual acuity outcomes were significantly better in the PanOptix group (P < .01). Correspondingly, the binocular defocus curve of the PanOptix IOLs showed significantly better visual acuity between -1.00 and -3.00 diopters compared to the ReSTOR IOLs (P < .05). The PanOptix group showed higher contrast sensitivity scores than the ReSTOR group for 12 and 18 spatial frequencies in photopic conditions and for 18 spatial frequencies in mesopic conditions (P < .05). The average VF-14 score was similar between groups (P = .78). None of the patients required spectacles. CONCLUSIONS: Bilateral implanted PanOptix IOLs seem to provide better intermediate and near vision, defocus curve, and contrast sensitivity compared to mix-and-match implanted ReSTOR IOLs. However, similar vision-related quality of life and spectacle independence were achieved with both IOLs. [J Refract Surg. 2019;35(9):559-564.].

Evaluation of Long-Term Corneal Morphology After Photorefractive Keratectomy by In Vivo Confocal Microscopy and Specular Microscopy; 20-Year Follow-Up.

PURPOSE: To evaluate long-term corneal morphological changes after photorefractive keratectomy (PRK) using in vivo confocal microscopy (IVCM) and specular microscopy. METHODS: This comparative case-control study included 16 eyes of 8 patients who underwent PRK for mild to moderate myopia 20 years ago and 30 eyes of 15 sex- and age-matched healthy controls. Corneal epithelial cells, sub-basal nerves, keratocytes (anterior, midstromal, and posterior), and endothelial cells were evaluated in both groups 10 and 20 years after surgery. Long-term visual outcomes were also recorded. RESULTS: In vivo confocal microscopy examination revealed similar epithelial morphology, sub-basal nerve fiber morphology/density, mid/posterior stromal keratocyte density, and endothelial cell density between PRK patients and controls at their 10th and 20th year follow-up. Anterior stromal keratocyte density was lower at 10th year; however, it reached to control group value at 20th year follow-up. Extracellular matrix reflectivity was slightly higher, and there was a trace subepithelial corneal haze in PRK group (milder in 20th year than 10th year) compared with controls. At the 20th year, uncorrected distance visual acuity was 20/20 or more in 6 eyes (37.5%), 20/40 or more in 16 eyes (100%), and all eyes had corrected distance visual acuity of 20/20 or better (spherical equivalent -0.31±0.37 D). CONCLUSIONS: Photorefractive keratectomy in low to moderate myopia seems to be safe and effective method in the long term with preserving corneal morphology (including anterior stromal keratocyte and sub-basal nerve fiber density) and refractive outcomes as shown in this study. In appropriate patients, this method can be considered confidently.

Transepithelial Phototherapeutic Keratectomy Followed by Corneal Collagen Crosslinking for the Treatment of Pellucid Marginal Degeneration: Long-term Results.

PURPOSE: To evaluate visual, refractive, topographic, and aberrometric outcomes of transepithelial phototherapeutic keratectomy (PTK) + corneal collagen crosslinking in the treatment of pellucid marginal degeneration. METHODS: This retrospective study includes 20 eyes of 15 patients with pellucid marginal degeneration treated with transepithelial PTK + accelerated corneal collagen crosslinking. Visual acuity, refraction, topographic keratometry, pachymetry, and aberrations were recorded pretreatment and 6, 12, 24, and 36 months after treatment. RESULTS: Stabilization in visual acuity was observed throughout the 36 months of follow-up (P > 0.05). The cylindrical value was significantly lower (P < 0.05) during the follow-up compared with the baseline (4.97 ± 2.00, 3.86 ± 2.01, 3.92 ± 2.27, 2.87 ± 1.70, and 3.28 ± 3.12 D at the baseline and postoperative 6th, 12th, 24th, and 36th month, respectively). Spherical equivalent was significantly lower at the 24th (P = 0.02) and 36th month (P = 0.01) follow-up intervals. A significant decrease (P < 0.05) in average keratometry readings was observed in all follow-up points (47.12 ± 4.66, 46.65 ± 4.38, 46.57 ± 4.57, 46.46 ± 4.81, and 46.27 ± 4.46 D, respectively). The maximum keratometry value remained stable (P > 0.05) in all visits (64.30 ± 10.70, 63.49 ± 10.05, 62.97 ± 9.50, 63.33 ± 10.06, and 62.27 ± 10.36 D, respectively). The Baiocchi Calossi Versaci index was significantly lower (P < 0.05) at all follow-up points compared with the baseline (3.21 ± 1.93, 2.99 ± 1.96, 2.96 ± 1.93, 2.82 ± 1.95, and 2.86 ± 1.99 µm, respectively). Central and minimum corneal thicknesses were significantly lower (P ≤ 0.01) compared with the baseline throughout the follow-up. Higher order aberration, trefoil, coma, and spherical aberration values remained stable during the follow-up compared with the baseline (P > 0.05). CONCLUSIONS: The combination of transepithelial PTK with accelerated corneal collagen crosslinking seems to be an effective treatment in patients with pellucid marginal degeneration in the long-term.

Blunt Scissors Stromal Dissection Technique Compared With Big-Bubble Deep Anterior Lamellar Keratoplasty.

OBJECTIVES: To evaluate the clinical findings and results of new modified manual deep anterior lamellar keratoplasty (M-DALK) technique compared with a big-bubble DALK (BB-DALK) technique in eyes with corneal scars or lesions. METHODS: A prospective, nonrandomized, comparative study included 65 eyes of 65 patients treated by M-DALK using the blunt scissors lamellar dissection technique or standard BB-DALK. Visual acuity, endothelial cell density, corneal cylinder (Cyl), central corneal thickness (CCT), residual stromal thickness and aberrometric values were recorded pre-treatment and 1, 3, 6, 12 and 18 months after treatment. RESULTS: Thirty-five eyes of 35 patients underwent deep anterior lamellar keratoplasty (DALK) with successful big-bubble technique, whereas 30 eyes of 30 patients underwent DALK with manual technique (in 10 eyes as a primary technique, in 20 eyes as a secondary technique). Successful big-bubble formation was achieved in 35 of 55 (64%) eyes. Microperforations occurred in three eyes in BB-DALK group, in six eyes in M-DALK group, and DALK could be completed successfully in these eyes. Visual acuity and endothelial cell loss results were not significantly different between groups during follow-up period. Mean CCT was significantly different between groups (P=0.035). Mean corneal Cyl, residual stromal thickness, and aberrometric values were similar between groups (P>0.05) at the final visit. CONCLUSION: New modified M-DALK technique has similar clinical findings and results with BB-DALK when using as a primary or secondary approach.

Comparison of phacoemulsification parameters between manual and femtosecond laser-assisted cataract surgery.

OBJECTIVE: To compare the nucleus removal time (NRT) and cumulative dissipated energy (CDE) outcomes of traditional phacoemulsification and femtosecond laser-assisted cataract surgery (FLACS) performed by cornea attendings and fellows. DESIGN: Prospective nonrandomized comparative study. PARTICIPANTS: A total of 410 eyes of 410 patients. METHODS: Nucleus removal time and CDE were recorded from patients who underwent cataract surgery using either FLACS (Catalys, LenSx, or Victus) or traditional phacoemulsification technique performed by 3 cornea attendings and 4 cornea fellows. One-way analysis of variance with Bonferroni post hoc tests and unpaired t tests were used to determine the differences between groups. RESULTS: There was no statistically significant difference in cataract grade between groups. NRT was significantly lower only when using the Catalys system compared with the LenSx and Victus platforms and the traditional surgery, in both the attending group (p = 0.006, p = 0.002, p < 0.000, respectively) and the fellow group (p = 0.049, p = 0.038, p = 0.011, respectively). With respect to CDE, there was no significant difference when using the laser systems compared with the traditional surgery in both attending and fellow groups (p > 0.05). NRT and CDE were significantly higher in the fellow group (NRT = 269.10 ± 117.67, CDE = 7.30 ± 4.83) compared with the attending group (NRT = 218.87 ± 109.67, CDE = 5.76 ± 3.66) in traditional cases; however, in FLACS cases, there was no significant difference in NRT and CDE between the fellow group and the attending group. CONCLUSIONS: Inexperienced surgeons seem to require more time and use more ultrasound energy during traditional phacoemulsification when compared with experienced surgeons. The use of FLACS seems to significantly improve the NRT of experienced and inexperienced surgeons.