Comparing morphologic features and complications of main clear corneal incision between junior and senior residents observed using anterior segment optical coherence tomography.

Background: Wound construction is a critical step in phacoemulsification. Using anterior segment optical coherence tomography (AS-OCT), we compared the morphological features and complications of main incisions made by junior or senior residents during phacoemulsification. Methods: This cross-sectional comparative study included eyes with senile cataracts that underwent uneventful phacoemulsification with a clear corneal incision made by seven senior and eight junior ophthalmology residents. All eyes underwent postoperative image acquisition using AS-OCT on day one and at three months, examining for morphological features and potential complications of the main incision. Results: We included 50 eyes of 50 patients with a male-to-female ratio of 22 (44%) to 28 (56%); 26 (52%) were operated on by junior residents and 24 (48%) by seniors. The mean geometric features of the main incisions and the frequency of early and late wound complications were comparable between the two groups (all P > 0.05). A significant correlation was found between the incision length and angle with the superior (r = + 0.80; P < 0.001 and r = - 0.63; P < 0.001, respectively) and inferior (r = + 0.84; P < 0.001 and r = - 0.68; P < 0.001, respectively) areas of the incision, as well as between the length and angle of incision (r = - 0.74; P < 0.001). The number of planes in the wound architecture was not significantly different according to senior or junior resident status (P > 0.05). Although the number of eyes with stromal hydration was significantly greater for junior residents than for seniors (P < 0.001), the corneal thickness at the entrance to the cornea or the anterior chamber, presence of endothelial wound gaping, and Descemet's membrane detachment were comparable between eyes with and without stromal hydration (all P > 0.05). At three months, 29 (58%) patients returned for examination, in whom seven (24%) had late wound complications. Conclusions: This study found no significant differences in the performances of junior and senior residents in terms of wound construction or its associated complications. However, considering the overall rate of some observed wound-related complications, we recommended revision of the resident educational curriculum concerning the structure and complications of the main incision.

Topographic properties of the cornea in welders.

PURPOSE: The aim of the present study was to evaluate the topographic status of the welders' corneas. METHODS: In this historical cohort, a group of welders (with at least 5 years' experience in welding) and a control group were assessed and compared. Lack of exposure to welding for 3 months or more was considered an exclusion criterion. In all participants, after taking a complete history of visual and ocular problems, both eyes underwent Pentacam imaging. Then, all subjects received slit lamp biomicroscopy for evaluation of ocular surface diseases. RESULTS: The data of 140 welders (mean age: 46.66 ± 13.01 years) and 172 controls (mean age: 45.05 ± 12.61 years) were analyzed. The welders' corneas had significantly higher eccentricity (p < 0.0001), keratometry readings (p < 0.0001), and cylinder power (p < 0.0001). The central, inferior, and nasal cornea were significantly thinner in the welders than in controls (p < 0.0001) while the difference was not significant in the superior and temporal cornea. All indices of corneal irregularity except for the central keratoconus index (CKI) and index of height asymmetry (IHA) were higher in welders compared to the control group (p < 0.0001). CONCLUSION: According to the results of this study, the welders' corneas are topographically irregular. Welders exhibit characteristics like steeper keratometry readings; higher eccentricity indexes; thinner central, inferior, and nasal corneas; and higher indices of corneal irregularity, especially the CK index. Long-term ultraviolet exposure may be a possible reason for these corneal changes.

A Comparative Assessment of Intraoperative Complication Rates in Resident-Performed Phacoemulsification Surgeries According to Najjar-Awwad Preoperative Risk Stratification.

INTRODUCTION: Phacoemulsification cataract surgery presents a challenge to resident surgeons with lower experience, which confronts with patient safety. In this study, we compared major intraoperative surgical complications of resident-performed phacoemulsification surgeries between cases with low intraoperative risk and random cases with unknown intraoperative risk. METHODS: This prospective randomized controlled study was done on patients who underwent phacoemulsification surgery by third- and fourth-year residents in Khatam-al-Anbia eye hospital, Mashhad, Iran. Preoperative risk was calculated using Najjar-Awwad risk score after slit lamp examination and the patients with scores 7 or higher were considered high-risk. Patients were randomly assigned into a study group, in which only low-risk cases were operated by third-year residents, or control group, in which third-year residents were able to operate any patient regardless of the risk score. In both groups, the remaining patients were operated by fourth-year residents. All intraoperative complications were recorded. Data were analyzed using SPSS, considering P<0.05 significant. RESULTS: Overall, 475 patients with cataract in the study (N=232) and control (N=243) groups were operated. Mean overall Najjar-Awwad risk scores did not differ significantly between the groups, but pseudoexfoliation and poor pupil dilatation occurred significantly more frequently in the control group (P=0.010 and P=0.014, respectively). Overall, 36 surgeries in the study group (15.5%) and 47 surgeries in the control group (19.3%) were complicated (P=0.273). There was a significant difference between the third- and fourth-year residents regarding the inability to complete continuous curvilinear capsulorhexis (P=0.033). The risk of overall and major complications in high-risk cases was significantly higher among those operated by 3rd-year residents compared with those operated by 4th-year residents (OR=3.45, 95% CI=1.2-9.9, P=0.016 and OR=6.37, 95% CI=1.99-20.34, P=0.001, respectively). CONCLUSION: Although supervised resident-performed phacoemulsification has a relatively safe learning curve in our residency program, it is best to stratify preoperative risk and assign high-risk cases to senior residents with higher experience.

The ocular surface status in individuals having long-term exposure to ionizing X-radiations.

PURPOSE: The present investigation was done to assess the status of tear film and corneal topography in individuals with long-term exposure to X-ray. METHOD: This historical cohort study was carried out to compare the lacrimal and corneal findings between radiographers (n = 126) and non-radiographers (n = 172). Radiographers included individuals with at least 5 years of experience in radiography while subjects in the control group had no history of exposure to X-ray. The Ocular Surface Disease Index (OSDI) was filled out by all individuals. Besides, the Pentacam imaging of both eyes was done. Finally, the lacrimal tests including tear break-up time and Schirmer (with anesthesia) were performed for both eyes of the participants. RESULTS: The mean values of the Schirmer and Tear breakup time (TBUT) in the radiographer group (Schirmer: 11.1 ± 3.2 mm, TBUT: 11.3 ± 4.1 s) were significantly lower than the values in control group (14.6 ± 8.1 mm, TBUT: 12.8 ± 4.8 s) (P < 0.0001). The mean OSDI score of the radiographers was significantly higher compared to the control group (24.1 ± 17.6, and 12.3 ± 12.4 respectively (P < 0.0001)). The corneal thickness in the center, inferior, superior, temporal and nasal parts was significantly higher in radiographers versus the control group. In addition, the maximum thickness difference was observed in temporal part (34.00 µm thicker) (P < 0.0001). On the other hand, the corneal eccentricity factor was lower in radiographers compared to the control group (P < 0.0001). CONCLUSION: Based on the findings of this study, it is concluded that the radiographers have thicker and flatter corneas are than the corneas of the subjects in the control group. However, their corneas had no irregularities. Regarding the tear point, a higher prevalence of dry eye symptoms was observed in the radiographers compared to the control group.

Tear film secretion and stability in welders.

PURPOSE: Welders are prone to ocular injuries and ocular surface problems due to exposure to ultraviolet light. The aim of this study was to evaluate the tear film comprehensively and assess objective and subjective indices of dry eye in welders. METHODS: In this historical cohort, welders with at least 5 years of experience were compared with controls. A complete evaluation of ocular health was done for all participants. The Schirmer test (invasive and non-invasive) and Invasive Tear Break-Up Time (ITBUT) were applied for objective evaluation and the Ocular Surface Disease Index (OSDI) was used for subjective assessment of the tear film status. The results were compared between the two groups using the SPSS software. RESULTS: The results of 140 welders (mean age: 46.66 ±â€¯13.01 years) and 172 controls (mean age: 45.05 ±â€¯12.61) were analyzed. The values of the Schirmer test and ITBUT were significantly lower in welders than controls; the difference was more prominent for the Schirmer test as compared to TBUT (Schirmer difference = 4.98 mm, ITBUT difference = 2.23 s). OSDI values were also significantly lower in welders than controls (P < 0.001). Considering a cut-off point of 12, 81.2% of welders had degrees of dry eye which was severe in 46.2% while 35.5% of controls had dry eye. CONCLUSION: The results indicate that the percentage of dry eye and tear problems is far higher in welders than non-welders. Most of the affected welders have severe dry eye. It seems that the main reason for dry eye in these people is aqueous deficiency.

Endothelial cell changes after photorefractive keratectomy with graded usage of mitomycin C.

PURPOSE: To compare differences in the endothelial cells before and after photorefractive keratectomy (PRK) for myopia with refractive error graded mitomycin C (MMC) application. METHODS: In a prospective randomized clinical trial, forty-eight myopic patients referred to Khatam-al-Anbia Eye Hospital, Mashhad, Iran, for PRK. Patients were treated with PRK by a Bausch and Lomb Technolas 217z excimer laser (Bausch and Lomb, Rochester, NY). MMC was applied after PRK 5 s for each diopter of spherical equivalent myopic refractive error corrected. The manifest refraction, visual acuity, MMC treatment length, corneal pachymetry and specular microscopy were evaluated preoperatively and at 1 and 6 months postoperatively. RESULTS: A total of 48 cases (96 eyes, 68.75% female) were treated, with a mean age of 26.70 ± 4.89 years (range, 18-34 years). Postoperative cell density, cell size and polymegathism did not significantly change. On the other hand, standard deviation (SD) of cell size (P = 0.008), pleomorphism (P = 0.003) and coefficient of variation (CV) (P = 0.016) were significantly increased. None of these parameters was related to the length of MMC application. Corneal thickness decreased significantly after the operation but it increased 6 months postoperatively compared with the first month (P < 0.001). CONCLUSION: MMC application for PRK in myopia can affect the endothelial cells, but in early follow-ups, it does not affect the cell density or size. Cell size was changed but it was obvious not in mean cell size, but in SD and CV. MMC time below the 30 s was not significant on endothelial cell changes.

Evaluation of transforming growth factor-beta1 gene expression in pterygium tissue of atopic patients.

BACKGROUND: The exact pathogenesis of pterygium is still not fully understood. Growth factors are considered to play an important role in the formation of pterygium. Transforming growth factor (TGF)-ß1 is considered to be one of the main mediators of fibroblast stimulation and tissue remodeling in allergic conditions. The objective of the present study was to investigate the association between TGF-ß1 gene expression and pterygium in atopic and nonatopic participants. METHODS: We used questionnaires to record demographic and clinical information from patients who underwent pterygium excision surgery. Skin prick examination was done to confirm or rule out atopy in 30 patients with atopy (Case Group) and 30 individuals without atopy (Control Group). Additionally, measurement of serum immunoglobulin E, cytokines, including interleukin-4 and interferon-γ, and peripheral blood eosinophil count was performed to confirm atopy in 30 consecutive patients (Case Group). A semiquantitative reverse transcription polymerase chain reaction was performed to determine TGF-ß1 gene expression in all individuals. RESULTS: TGF-ß1 mRNA gene expression was significantly higher (p = 0.0001) in atopic patients 2.50 ± 1.11 compared to nonatopic individuals 1.40 ± 0.46. Eosinophil count and serum immunoglobulin E were significantly higher (p = 0.031 and p = 0.001, respectively) in atopic patients compared to the Control Group. Serum interleukin-4 was also significantly higher (p = 0.01) in atopic patients compared with nonatopic individuals. CONCLUSION: Excess expression of TGF-ß1 gene in pterygium tissue of atopic individuals suggests that growth factors play a role in the pathogenesis of pterygium.

A comparative study on visual and optical performance of Akreos AO and Kontur AB IOLs after phacoemulsification cataract surgery.

PURPOSE: Akreos AO and Kontur AB are two commonly used intraocular lenses (IOLs) in Iran. This study was designed to evaluate the visual performance of these lenses. METHODS: In a comparative interventional study, 35 patients (70 eyes) were recruited, and each IOL was implanted in one eye of the patients, randomly. Best corrected visual acuity (BCVA), contrast sensitivity, aberrometric analysis, and depth of focus were evaluated 1 month and 3 months postoperatively. A visual quality questionnaire was also filled for each eye, and the results were compared. RESULTS: Mean age of the patients was 60.97 ± 7.00 years. BCVA was not significantly different between the two eyes, before, 1 month, and 3 months postoperatively (p > 0.05 for all). Photopic and mesopic contrast sensitivity was not different between the two lenses instead of photopic 18 cycles per degree, 3 months postoperatively and in mesopic 6 cycles per degree 1 month postoperatively (p = 0.034 and p = 0.002, respectively). Aberrometric factors including HoRMS, Total RMS, and Higher order without Z(4,0) were not significantly different between the two lenses (p > 0.05 for all), but they were slightly lower for Akreos AO. Post-operative distance-corrected visual acuity for intermediate and near vision were not different between the two groups (p > 0.05, respectively). CONCLUSION: Visual performance of Akreos AO and Kontur AB is similar. However, contrast sensitivity and aberrometric parameters are slightly better for Akreos AO IOL.

Stereoacuity after photorefractive keratectomy in myopia.

PURPOSE: Stereopsis, as a part of visual function, is the ability of differentiating between the two eyes' views (binocular disparity), due to the eyes' different positions. The aim of this study was to compare stereoscopic vision before and after photorefractive keratectomy (PRK) in myopia. METHODS: In a prospective interventional case series study clinical trial, forty-eight myopic individuals (age range: 18-34 years) who had undergone PRK surgery by a Bausch & Lomb Technolas 217z excimer laser were included. In all patients, stereoscopic vision was assessed using TNO test charts at 40 cm distance preoperatively and at 3 and 6 months postoperatively. RESULTS: A total of 48 cases (96 eyes, 69% female) with a mean age of 26.70 ± 4.89 years (range: 18-34 years) were treated. Uncorrected visual acuity (UCVA) was improved and refraction was corrected significantly after PRK surgery. The stereoscopic vision in patients was 246.56 ± 98.43 s of arc before PRK surgery. Postoperatively, the stereoacuities were recorded as 365.38 ± 112.65 s of arc and 343.51 ± 88.96 s of arc at 3 and 6 months, respectively. These differences were statistically significant (p < 0.001). CONCLUSION: PRK was successful and safe in improving refractive error and UCVA, but it may deteriorate the stereoscopic vision. It may be due to an increase in higher order aberrations.

Aspheric versus wavefront-guided photorefractive keratectomy: contralateral eye study.

PURPOSE: To compare the refractive, visual, and aberrometric outcomes between wavefront-guided photorefractive keratectomy (PRK) and aspheric PRK in myopic patients. SETTING: Khatam-al-Anbia Eye Hospital, Mashhad, Iran. DESIGN: Prospective randomized clinical trial. METHODS: One eye of each patient was randomly assigned to excimer laser wavefront-guided PRK (Zyoptix) and the other eye to excimer laser aspheric PRK (Technolas 217z). The preoperative and 3-month and 6-month postoperative refractive errors, visual acuity, contrast sensitivity, and higher-order aberrations (HOAs) were compared between the groups. RESULTS: Ninety-six eyes (48 patients) were enrolled. At the last postoperative visit, there were no between-group differences in uncorrected distance visual acuity (UDVA) (P = .987) or corrected distance visual acuity (P = .416). The mean spherical equivalent was -0.076 diopter (D) ± 0.029 (SD) in the wavefront-guided group and -0.077 ± 0.075 D in the aspheric PRK group (P = .684). Postoperatively, the mean area under the log of contrast sensitivity function (AULCSF) with and without glare testing improved over preoperative values (both P < .001). There was no statistically significant between-group difference in the AULCSF with glare (P = .903) or without glare (P = .978). Total HOAs increased after PRK in both groups, although aspheric PRK induced fewer HOAs than wavefront-guided PRK (P = .04). CONCLUSIONS: Both PRK methods equally improved postoperative UDVA and contrast sensitivity. The HOAs increased after treatment with both methods; however, aspheric ablation induced statistically fewer HOAs than wavefront-guided ablation. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Angle Kappa Measurements: Normal Values in Healthy Iranian Population Obtained With the Orbscan II.

BACKGROUND: The angle kappa is important in proper centration of corneal ablation in keratorefractive surgery. Orbscan II device is widely used preoperatively in photoablation surgeries and can be used to measure the angle kappa. OBJECTIVES: This study aimed to determine the mean angle kappa and its intercepts in healthy young Iranian adults. PATIENTS AND METHODS: In this cross-sectional study, orthotropic patients (age range, 18-35 years) who were referred to the Khatam Eye Hospital (Mashhad, Iran) were included. Exclusion criteria were as follows: history of any eye deviation or strabismus with or without orthoptic or surgical treatment; any intraocular, corneal, or keratorefractive surgery; contact lens use; any corneal anomaly; any ophthalmic or systemic drug consumption; and hyperopic spherical refraction > + 3.00 diopters (D), spherical refraction > -5.00 D, or cylindrical refraction > 2.00 D. All of the parameters were measured by the same operator through an Orbscan II device. RESULTS: A total of 977 healthy participants who aged 18 to 45 years were included consecutively. The study population consisted of 614 females and 363 males. The average angle kappa was 5.00º ± 1.36º at 240.21º ± 97.17º in males and 4.97º ± 1.30º at 244.22º ± 94.39º in females (P = 0.63). The average horizontal (x-axis) angle kappa was -0.02º ± 0.49º, with a mean of -0.02º ± 0.50º in males and -0.02º ± 0.49º in females (P = 0.93). The average vertical (y-axis) angle kappa was -0.09º ± 0.32º, with a mean of -0.09º ± 0.33º in males and -0.09º ± 0.32º in females (P = 0.74). CONCLUSIONS: By using the normal angle kappa determined in this study, pseudodeviations can be identified more precisely in those who might undergo keratorefractive surgery.

Effectiveness of Technolas torsional eye tracking system on visual outcomes after photorefractive keratectomy.

PURPOSE: To investigate the efficacy of Technolas 217Z eye tracking system (torsional component) in corneal surface irregularity and high order aberrations (HOAs) after photorefractive keratectomy. METHODS: Patients with compound myopic astigmatism among persons demanding refractive surgery in Khatam-al-Anbia Eye Hospital with the mean age of 29 years were enrolled in this double-blind randomized interventional study. The mean spherical equivalent (SE) of refractive error was -4.75 diopters(D) (range: -1.5 to -7.0), and the mean astigmatism was 3 D (range:1.0-4). Many studies were performed for each patient including: A complete eye examination, visual acuity and Monocular contrast sensitivity evaluation, and refraction. Corneal topography, Orbscan II, and wavefront aberrometry were conducted. One eye was randomly assigned for aspheric treatment and applying eye tracking system. The other eye was treated without torsional eye tracking system. The outcome measures were uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), contrast sensitivity, corneal irregularity index in 3 mm and 5 mm optical zones in Orbscan II, and mean total HOAs at the 6-monthvisit. RESULTS: Fifty eyes of 25 patients were enrolled. Mean UCVA was improved significantly in both the study and control groups in the 6-month post-operative follow-up. There was no significant difference between the 2 groups in UCVA and BCVA (P = 0.185 and P = 0.176, respectively). Total HOAs increased in both groups after PRK. However, they were lower in eyes treated with the eye tracking system (P < 0.001). Corneal irregularity index in 3 mm and 5 mm central zones in Orbscan II was significantly lower in the study group (P = 0.045 and P = 0.031 respectively). Contrast sensitivity function was not different in the 2 groups (P = 0.15). CONCLUSION: Our study findings suggest that applying 'Technolas 217z' eye tracker system (Bausch and Lomb Advanced) results in a more regular anterior surface of cornea. Therefore, we recommend it for surface laser refractive surgery.

The expression of vascular endothelial growth factor in pterygium tissue of atopic patients.

The exact pathogenesis of pterygium has not been completely elucidated. Growth factors have been considered to play a role in pterygium formation. Vascular endothelial growth factor (VEGF) is one of the principal mediators of angiogenesis, fibroblast stimulation and tissue remodeling in allergic conditions. The aim of this study was to compare the association between pterygium and VEGF gene expression between atopic and non-atopic individuals. At first visit, all patients with pterygium underwent blood tests, serum immunoglobulin E (IgE), serum cytokines including interleukin-4 (IL-4) and interferon-γ (IFN-γ) and peripheral blood eosinophil count. After obtaining informed consents, questionnaires were used to obtain demographic and clinical data from patients who underwent pterygium excision surgery. Skin prick test was performed to confirm or rule out atopy in 30 patients with (case group) and 30 patients without (control group) atopy. Pterygium tissues were then removed by surgery. A semi-quantitative reverse transcriptase polymerase chain reaction was performed to determine VEGF gene expression in all patients. Our results illustrated that VEGF mRNA expression in atopic patients was significantly higher than in the non-atopic group (P = 0.01). Eosinophil count, serum IgE and IL-4 were also significantly higher in atopic patients than in the non-atopic group (P = 0.03, 0.001 and 0.001, respectively). However, no significant difference was noted in serum IFN-γ between the two groups (P = 0.06). The excessive expression of VEGF gene in pterygium tissue of patients with atopy suggests that growth factors may play a role in the pathogenesis of pterygium or accelerate its formation.

Anterior and posterior corneal curvature: normal values in healthy Iranian population obtained with the Orbscan II.

The objective of study was to determine the normative values of anterior and posterior best fit sphere (A-BFS and P-BFS) measured with Orbscan II Topography System. In this cross-sectional study, patients (age range: 18-40 years) referred to the Khatam Eye Hospital (Mashhad, Iran) were put in an observational cross-sectional study. The A-BFS and P-BFS were measured with the Orbscan II. The differences between genders, between right and left eyes, and age-related changes were evaluated. A total of 977 healthy participants consisted of 614 female and 363 male subjects aged 18-35 years participated. The average A-BFS in our study population was recorded as 43.060 ± 1.541 D (median: 43.00 D, mode: 43.10 D, range: 38.80-55.80 D). The average P-BFS in our study population was recorded as 52.702 ± 2.190 D (median: 52.60 D, mode: 53.10 D range: 46.9-62.20 D). The A-BFS and P-BFS were respectively 42.753 ± 1.629 and 52.327 ± 2.376 D in males and 43.242 ± 1.457 and 52.924 ± 2.041 D in females, which were statistically different between the genders (P < 0.001). However, A-BFS and P-BFS were not statistically different between right and left eyes (P = 0.649 and P = 0.688 respectively). In addition, A-BFS and P-BFS were not correlated with the age (r = 0.038, P = 0.096 and r = -0.142, P = 0.178 respectively). Considering 95 % confidence interval, A-BFS less than 43.13 D and greater than 42.99 D and P-BFS less than 52.80 D and greater than 52.60 D would be considered abnormal. Detailed description and analysis of A-BFS and P-BFS with Orbscan demonstrated that the obtained average value of BFS were higher in male than female and did not change with increasing age.

White-to-white corneal diameter: normal values in healthy Iranian population obtained with the Orbscan II.

AIM: To determine the normative values of white-to-white corneal diameter with Orbscan II Topography System and to compare right and left eyes data in the normal young population. METHODS: A total of 1001 healthy participants aged 18-45y participated in this observational cross-sectional study. The study population consisted of 616 female and 385 male subjects. The corneal diameter was measured with the Orbscan II. The differences between genders, between right and left eyes and age-related changes were evaluated. Statistical analyses were performed using Student's t-test. RESULTS: The average white-to-white distance in our study population was recorded as 11.65±0.36 mm (median: 11.60 mm, mode: 11.70 mm, minimum: 10.50 mm and maximum: 13.60 mm). The white-to-white distance was 11.60±0.35 mm in males and 11.71±0.36 mm in females which was statistically different between genders (P<0.01). However, white-to-white distance was not statistically different between right and left eyes. In addition, this parameter decreased with increasing age. Considering 95% confidence interval, corneal diameter less than 10.93 mm and greater than 12.34 mm would be considered as microcornea and megalocornea, respectively based on this study population, using the Orbscan II topography. CONCLUSION: Detailed description and analysis of corneal diameter with Orbscan demonstrate that the obtained average value of horizontal white-to-white is higher in male than female and decreases slightly with increasing age. Our data also suggests the cut off values for definition of microcornea and megalocornea, which can be employed with this population.

Angle kappa changes after photorefractive keratectomy for myopia.

The goal of this study was to compare differences in the mean angle kappa and its intercepts before and after photorefractive keratectomy (PRK) for myopia. In a prospective controlled study, myopic patients were treated with aspheric wavefront-guided (personalized) PRK with a Bausch & Lomb Technolas 217z excimer laser. The manifest refraction, visual acuity, and angle kappa were evaluated preoperatively and at 1 and 6 months postoperatively. The same operator performed all angle kappa measurements using Orbscan IIz. A total of 48 cases (96 eyes, 68.75 % female) with a mean age of 26.70 ± 4.89 years (18-34 years) were treated. The preoperative and postoperative mean angle kappa values were not significantly different (4.97 ± 1.24 vs 4.99 ± 1.10 at 6 months). The average horizontal distance (x-intercept) between the visual axis and pupillary axis intersection on the corneal surface measured before surgery (-0.562 ± 0.074 mm) did not significantly differ from the values measured at 1 and 6 months after surgery (-0.559 ± 0.048 and -0.554 ± 0.055 mm, respectively). Similarly, the average vertical distance (y-intercept) values did not differ before and at 1 and 6 months after surgery (0.156 ± 0.225, 0.142 ± 0.040, and 0.149 ± 0.33 mm, respectively). No differences in the angle kappa or its corneal intercepts were observed between pre- and post-PRK. This finding implies that PRK does not change the corneal vertex locations.

Anesthetic keratopathy presenting as bilateral Mooren-like ulcers.

This observational case report describes the development of bilateral Mooren-like ulcers in a patient with anesthetic keratopathy. A 42-year-old man with a recent history of minor eye trauma and pain self-treated with tetracaine eye drops presented with complaints of acutely worsening vision and severe pain bilaterally. His visual acuity at presentation was limited to hand motion. Slit-lamp examination revealed bilateral epithelial defects at the center of the cornea, and an area of stromal infiltration and thinning with an undermining leading edge resembling a Mooren's ulcer in both eyes. Corneal haze and hypopyon were visible. Anesthetic use was halted immediately and the patient was started on prednisolone and mycophenolate mofetil (Cellcept(®)), after which visual acuity gradually improved and pain decreased. Despite improvement of symptoms, residual epithelial defects remained, and the patient was ultimately treated with keratoplasty for recovery of vision. We suggest that anesthetic keratopathy should be included in the differential diagnosis for any patient presenting with ring-shaped stromal infiltrates or nonhealing epithelial defects.

Infectious scleritis after subtenon triamcinolone acetonide injection.

PURPOSE: To report a case of Staphylococcus epidermidis infection after subtenon injection (STI) of triamcinolone acetonide (TA). DESIGN: Interventional case report. METHODS: A 20-year-old patient with corneal graft rejection received STI of TA after insufficient response to topical and oral corticosteroids. RESULTS: After conjunctival necrosis, necrotizing scleritis progressed although topical and systemic steroids were discontinued. Systemic ciprofloxacin, topical fortified amikacin, and vancomycine drops were used. Complete recovery was obtained after 3 weeks. Smears and cultures showed Staphylococcus epidermidis infection. CONCLUSIONS: Although uncommon, infectious scleritis can occur following uncomplicated subconjunctival corticosteroid injections. Infectious scleritis can be very difficult to diagnose as it may mimic an immune mediated disease. If the conjunctiva is suspected to be involved, a smear should always be taken. Prevention by sterilizing the injection site (prep and drape) and strong antibiotic prophylaxis are recommended to reduce the risk of the infectious scleritis.

The effects of riboflavin/ultraviolet: a corneal cross-linking on the signs and symptoms of bullous keratopathy.

PURPOSE: To evaluate the effectiveness of corneal cross-linking in improving the signs and symptoms of bullous keratopathy. MATERIALS AND METHODS: This prospective non-randomized case series evaluated 20 eyes with bullous ketratopathy that underwent corneal cross-linking (C3R) with riboflavin and ultraviolet-A (UVA, 370 nm, 3 mW/cm(2)). C3R was performed for 30 min in a routine procedure after removal of epithelium. Central corneal thickness (CCT), corneal haze, visual acuity (VA), and the presence of irritating symptoms were recorded before the procedure, and at 1 week, 1 months, 3 months, and 6 months after the procedure. RESULTS: The mean CCT was 872 ± 162 µm (range: 665-1180 µm) before the procedure. Following the procedure, CCT was 855 ± 175 µm after 1 week, 839 ± 210 µm after 1 month, 866 ± 185 µm after 3 months, and 863 ± 177 µm after 6 months (P>0.05, all visits). There was no significant improvement in VA or corneal clarity after 6 months. Improvement of the following symptoms: burning, pain, and foreign body sensation were reported after 6 months by 83.3%, 75.0%, and 66.7% of patients, respectively. Persistent epithelial defect occurred in five patients (25%) resolved with frequent lubrication and bandage contact lenses. CONCLUSION: The outcomes of this study indicate corneal cross-linking is not an effective treatment for bullous keratopathy with respect to VA and CCT, although it can improve irritation and discomfort.

Correlation between Corneal Endothelial Cell Loss and Location of Phacoemulsification Incision.

PURPOSE: To assess the relationship between corneal endothelial cell loss after phacoemulsification and the location of the clear corneal incision. METHODS: A total of 92 patients (92 eyes) with senile cataracts who met the study criteria were included in this cross sectional study and underwent phacoemulsification. The incision site was determined based on the steep corneal meridian according to preoperative keratometry. Endothelial cell density was measured using specular microscopy in the center and 3 mm from the center of the cornea in the meridian of the incisions (temporal, superior, and superotemporal). Phacoemulsification was performed by a single surgeon using the phaco chop technique through a 3.2 mm clear cornea incision. Endothelial cell loss (ECL) was evaluated 1 week, and 1 and 3 months postoperatively. RESULTS: At all time points during follow-up, ECL was comparable among the 3 incision sites, both in the central cornea and in the meridian of the incision (P > 0.05 for all comparisons). However, 3 months postoperatively, mean central ECL with superior incisions and mean sectoral ECL with temporal incisions were slightly higher. Superotemporal incisions entailed slightly less ECL than the other 2 groups. Overall, one month after surgery, mean central ECL was 10.8% and mean ECL in the sector of the incisions was 14.0%. Axial length and effective phaco time (EFT) were independent predictors of postoperative central ECL (P values 0.005 and < 0.0001, respectively). CONCLUSION: A superotemporal phacoemulsification incision may entail less ECL as compared to other incisions (although not significantly different). The amount of central ECL may be less marked in patients with longer axial lengths and with procedures utilizing less EFT.