Head to head comparison of diagnostic performance of three non-mydriatic cameras for diabetic retinopathy screening with artificial intelligence.

BACKGROUND: Diabetic Retinopathy (DR) is a leading cause of blindness worldwide, affecting people with diabetes. The timely diagnosis and treatment of DR are essential in preventing vision loss. Non-mydriatic fundus cameras and artificial intelligence (AI) software have been shown to improve DR screening efficiency. However, few studies have compared the diagnostic performance of different non-mydriatic cameras and AI software. METHODS: This clinical study was conducted at the endocrinology clinic of Akdeniz University with 900 volunteer patients that were previously diagnosed with diabetes but not with diabetic retinopathy. Fundus images of each patient were taken using three non-mydriatic fundus cameras and EyeCheckup AI software was used to diagnose more than mild diabetic retinopathy, vision-threatening diabetic retinopathy, and clinically significant diabetic macular oedema using images from all three cameras. Then patients underwent dilation and 4 wide-field fundus photography. Three retina specialists graded the 4 wide-field fundus images according to the diabetic retinopathy treatment preferred practice patterns of the American Academy of Ophthalmology. The study was pre-registered on clinicaltrials.gov with the ClinicalTrials.gov Identifier: NCT04805541. RESULTS: The Canon CR2 AF AF camera had a sensitivity and specificity of 95.65% / 95.92% for diagnosing more than mild DR, the Topcon TRC-NW400 had 95.19% / 96.46%, and the Optomed Aurora had 90.48% / 97.21%. For vision threatening diabetic retinopathy, the Canon CR2 AF had a sensitivity and specificity of 96.00% / 96.34%, the Topcon TRC-NW400 had 98.52% / 95.93%, and the Optomed Aurora had 95.12% / 98.82%. For clinically significant diabetic macular oedema, the Canon CR2 AF had a sensitivity and specificity of 95.83% / 96.83%, the Topcon TRC-NW400 had 98.50% / 96.52%, and the Optomed Aurora had 94.93% / 98.95%. CONCLUSION: The study demonstrates the potential of using non-mydriatic fundus cameras combined with artificial intelligence software in detecting diabetic retinopathy. Several cameras were tested and, notably, each camera exhibited varying but adequate levels of sensitivity and specificity. The Canon CR2 AF emerged with the highest accuracy in identifying both more than mild diabetic retinopathy and vision-threatening cases, while the Topcon TRC-NW400 excelled in detecting clinically significant diabetic macular oedema. The findings from this study emphasize the importance of considering a non mydriatic camera and artificial intelligence software for diabetic retinopathy screening. However, further research is imperative to explore additional factors influencing the efficiency of diabetic retinopathy screening using AI and non mydriatic cameras such as costs involved and effects of screening using and on an ethnically diverse population.

Evaluation of macular vascular density and foveal avascular zone changes by optical coherence tomography angiography (OCT-A) after intravitreal dexamethasone implant in diabetic macular edema resistant to Anti-VEGF treatment.

PURPOSE: Analysis of foveal avascular zone (FAZ) width and vascular density (VD) changes before and after intravitreal dexamethasone implant (IDI) treatment in diabetic macular edema (DME) patients resistant to anti-VEGF treatment. METHODS: In this retrospective study, patients who were regularly treated with at least 5 doses of intravitreal Anti-VEGF (bevacizumab, ranibizumab or aflibercept) for DME and whose DME continued were considered resistant to Anti-VEGF and were treated with IDI for the first time. Thirty-four eyes of 34 patients were included in the study. FAZ and VD values of optical coherence tomography angiography (OCT-A) scans at 0, 1 and 3 months were examined. RESULTS: In OCT-A measurements, the pre-IDI superficial plexus FAZ (SFAZ) area (0.350 ± 0.120 mm2) was decreased at 1 (0.292 ± 0.132 mm2, p < 0.001) and at 3 months (0.311 ± 0.153 mm2, p = 0.017). Pre-IDI deep plexus FAZ (DFAZ) area (0.651 ± 0.313 mm2) was decreased at 1-month post-IDI (0.481 ± 0.247 mm2, p < 0.001) while no significant change was observed at 3 months (0.575 ± 0.259 mm2, p = 0.197). There was no significant change in the mean post-IDI total VD rate in both superficial (pre 39.2% ± 2.4; 1st month 39.2% ± 2.6%; 3rd month 39.5% ± 3.4%) and deep retinal plexus (pre 43.3% ± 2.6%; 1st month 43.5 ± 2.8%; 3rd month 43.6% ± 4.6%) (p = 0.408 and p = 0.607, respectively). CONCLUSION: The study showed that IDI caused a significant decrease in the FAZ area without any change in VD in patients with DME resistant to the anti-VEGF agents. IDI might be related to a decrease in the macular ischemia secondary to diabetic retinopathy.

Retinal vascular density evaluated by optical coherence tomography angiography in macular telangiectasia type 2.

PURPOSE: To evaluate the retinal and choroidal vascular changes through optical coherence tomography angiography (OCTA) in patients with macular telangiectasia type 2 (MacTel 2). METHODS: Our study included 20 patients (40 eyes) with MacTel 2, and age-matched and sex-matched 18 subjects (36 eyes) in the control group. Fundus color photographs, fundus autofluorescence, fundus fluorescein angiography, spectral-domain optical coherence tomography and OCTA were performed. Foveal vascular density and parafoveal vascular density (PFVD), and foveal retinal thickness and parafoveal retinal thickness, choroidal thickness (CT) and retinal ganglion cell-inner plexiform layer (GCIPL) were compared between MacTel 2 patients and normal age-matched controls. RESULTS: The retinal whole vascular density and PFVD of the deep plexus were significantly lower in patients with MacTel 2 than that of the control group (56.93% vs. 58.54%, p = 0.003; and 60.38% vs. 61.66%, p = 0.045). The foveal avascular zone (FAZ) of the deep plexus was significantly enlarged in patients with MacTel 2 than that of the control group (0.44 vs. 0.36, p = 0.009). There was a positive and statistically significant correlation between the FAZ of the superficial and deep plexus and CT in patients with MacTel 2. There was a positive and statistically significant correlation between retinal whole, parafoveal temporal quadrant vascular density of the superficial and deep plexus and GCIPL thickness in patients with MacTel 2. CONCLUSIONS: Our study demonstrated that important retinal vascular density and FAZ changes in MacTel 2 occur in the deep capillary plexus of the retina.

Neutrophil/lymphocyte ratio and mean platelet volume in central serous chorioretinopathy.

PURPOSE: This study aimed to evaluate mean platelet volume (MPV) and neutrophil/lymphocyte ratio (NLR) values and their relationship with clinical findings in patients with central serous chorioretinopathy (CSCR). METHODS: Overall, 87 patients fulfilling inclusion criteria and 320 age- and sex-matched healthy individuals as controls were included in the study. The CSCR patients (n=87) were classified into 2 groups as acute CSCR (group 1, n=43) and chronic CSCR (group 2, n=44). RESULTS: It was found that NLR (P<0.05) and C-reactive protein (CRP) (P<0.05) values were higher in acute CSCR group than the other groups. MPV value was found to be higher in chronic CSCR group than the other groups (P<0.001). CONCLUSION: It seems that neutrophils play a major role in acute CSCR while platelets are involved in progression to chronic CSCR. Larger, prospective studies are needed on this topic.

Frequency of fibromyalgia syndrome in patients with central serous chorioretinopathy.

PURPOSE:: To investigate frequency of fibromyalgia syndrome (FMS) among patients with central serous chorioretinopathy (CSCR). METHODS:: The study included 83 patients with CSCR and 201 age- and sex-matched healthy controls; the mean age was 47.5 ± 11.3 years in the CSCR group (18 women; 21.7%) and 47.2 ± 11.2 years in the control group (44 women; 21.9%). All participants were assessed for FMS based on 2010 American College of Rheumatology diagnostic criteria and for depression and anxiety with the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). RESULTS:: FMS was diagnosed in 35 patients (42.2%) from the CSCR group and in 21 individuals (10.4%) from the control group (p<0.001). It was found in 77.77% of the women (14/18) and 32.3% of the men (21/65) in the CSCR group and in 22.7% of the women (10/44) and 7.0% of the men (11/157) in the control group. Familial stress, BDI and BAI scores were higher in the patients with FMS than in those without. When independent risk factors were evaluated by logistic regression analysis, it was found that only the presence of familial stress was a significant risk factor for FMS. CONCLUSIONS:: Patients with CSCR should be assessed for the presence of FMS, and this should be taken into consideration when developing a treatment plan. Further studies with a larger sample size are needed to clarify the relationship between FMS and CSCR.

Frequency of fibromyalgia syndrome in patients with central serous chorioretinopathy / Frequência de síndrome de fibromialgia em pacientes com coriorretinopatia serosa central

ABSTRACT Purpose: To ınvestigate frequency of fibromyalgia syndrome (FMS) among patients with central serous chorioretinopathy (CSCR). Methods: The study included 83 patients with CSCR and 201 age- and sex-matched healthy controls; the mean age was 47.5 ± 11.3 years in the CSCR group (18 women; 21.7%) and 47.2 ± 11.2 years in the control group (44 women; 21.9%). All participants were assessed for FMS based on 2010 American College of Rheumatology diagnostic criteria and for depression and anxiety with the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). Results: FMS was diagnosed in 35 patients (42.2%) from the CSCR group and in 21 individuals (10.4%) from the control group (p<0.001). It was found in 77.77% of the women (14/18) and 32.3% of the men (21/65) in the CSCR group and in 22.7% of the women (10/44) and 7.0% of the men (11/157) in the control group. Familial stress, BDI and BAI scores were higher in the patients with FMS than in those without. When independent risk factors were evaluated by logistic regression analysis, it was found that only the presence of familial stress was a significant risk factor for FMS. Conclusions: Patients with CSCR should be assessed for the presence of FMS, and this should be taken into consideration when developing a treatment plan. Further studies with a larger sample size are needed to clarify the relationship between FMS and CSCR.

RESUMO Objetivo: Investigar a frequência da fibromialgia (FMS) entre os pacientes com coriorretinopatia serosa central (CSCR). Métodos: O estudo incluiu 83 pacientes com CSCR e 201 controles saudáveis pareados por idade e sexo. Todos os participantes foram avaliados com base nos critérios de diagnóstico de FMS do American College of Rheumatology de 2010 (ACR), Beck Anxiety Inventory (BAI) e Beck Depression Inventory (BDI). Resultados: A idade média foi 47,53 ± 11,33 anos no grupo CSCR (18 mulheres; 21,7%) e 47,19 ± 11,19 anos (44 mulheres; 21,9%) no grupo controle. FMS foi diagnosticada em 35 pacientes (42,2%) do grupo CSCR e em 21 indivíduos (10,4%) do grupo controle (p<0,001). FMS foi encontrado em 77,77% das mulheres (14/18) e 32,3% dos homens (21/65) no grupo CSCR e em 22,7% das mulheres controles (10/44) e 7,0% dos homens controles (11/157). Estresse familiar, BDI e BAI foram maiores nos pacientes com FMS em comparação com aqueles sem FMS. Quando os fatores de risco independentes foram avaliados por análise de regressão logística, verificou-se que apenas a presença de estresse familiar foi um fator de risco significativo para FMS. Conclusões: Os pacientes com CSCR devem ser avaliados para presença de FMS e a FMS deve ser levada em consideração durante o desenvolvimento de um plano de tratamento. São necessários mais estudos com maior tamanho da amostra para esclarecer relações entre FMS e CSCR.

Keratoconus presenting with bilateral simultaneous acute corneal hydrops.

PURPOSE: To report a case of unknown keratoconus presenting with bilateral simultaneous acute corneal hydrops. METHODS: Case report. RESULTS: A case of a 12-year-old male patient with Leber congenital amaurosis (LCA) presented with sudden whitening and lacrimation for 2 days in both eyes simultaneously. At the initial examination, there were bilateral acute corneal hydrops, enophthalmic eyes and roving nystagmus. Ultrasonography revealed clear crystalline lenses and attached retina. Initial management consisted of topical hypertonic solutions, steroids and artificial tears. CONCLUSION: Bilateral simultaneous acute corneal hydrops has not been reported before in the literature. It may be the presenting sign of keratoconus.

The association of low-grade systemic inflammation with hypertensive retinopathy.

High-sensitivity C-reactive protein (hs-CRP) is a marker of systemic low-grade inflammation. The pathophysiologic mechanism of hypertensive retiopathy (HR) is not fully established. Elevated blood pressure (BP) alone does not fully account for the extent of retinopathy, other pathogenic mechanisms may be involved, such as low-grade inflammation. Therefore, this study was designed to answer the following questions. (i) Do hs-CRP levels change in HR? (ii) Is there any relation between degree of HR and hs-CRP levels? This study included 84 hypertensive patients with HR. The hypertensive patients were divided into two groups according to the Keith-Wagener classification. Group 1 comprised 42 patients with grade I HR, and Group 2 comprised 42 patients with grade II HR. We selected 42 healthy subjects matched for age, sex, and body mass index (BMI) for control group. The level of hs-CRP in group 2 was significantly higher than in group 1 group (p = 0.018) and control group (p = 0.001), it was also higher in group 1 than in control group (p = 0.002). Also, hs-CRP showed positive correlations with degree of HR (r = 0.29, p = 0.017). Our study suggests that there is a relationship between HR and hs-CRP levels, which may be associated with systemic low- grade inflammation.

Conversion to deep anterior lamellar keratoplasty (DALK): learning curve with big-bubble technique.

BACKGROUND AND OBJECTIVE: To report the perioperative complications and clinical outcomes of 50 deep anterior lamellar keratoplasty (DALK) cases. PATIENTS AND METHODS: Fifty eyes of 50 patients with pathologies involving the corneal stroma and sparing the Descemet's membrane and endothelium were included consecutively in this prospective, noncomparative interventional case series study. DALK was performed using the big-bubble technique. RESULTS: The most frequent indication for DALK surgery was keratoconus (26 eyes), followed by corneal dystrophy (10 eyes) and superficial corneal scar (14 eyes). The average follow-up period was 12.0 ± 3.9 months. DALK was completed in 41 cases (82%). A big bubble was achieved successfully in 37 cases (74%). Descemet's membrane perforations occurred in 14 (28%) eyes, 8 of which were macroperforation and necessitated conversion to penetrating keratoplasty. Complications tended to decrease throughout the study. Postoperative best-corrected visual acuity of 0.5 or better was present in 30 of 41 (73.2%) eyes that underwent DALK. There was no episode of graft rejection. CONCLUSION: DALK big-bubble technique may be a valuable procedure during transition from penetrating keratoplasty to anterior lamellar keratoplasty. It provided acceptable visual and refractive outcome even during the learning period in a variety of corneal lesions.

Serum ferritin levels correlate with hypertensive retinopathy.

BACKGROUND: In recent years several studies showed an association between body iron stores, represented by serum ferritin, and oxidative stress. The pathophysiological mechanism of hypertensive retinopathy (HR) is not fully established. Elevated blood pressure alone does not fully account for the extent of retinopathy; other pathogenic mechanisms may be involved, such as increased oxidative stress. Therefore this study was designed to determine whether ferritin levels change in HR and whether there is any relationship between the degree of HR and ferritin level. MATERIAL/METHODS: This study included 72 essential hypertensive patients with HR. The hypertensive patients were divided into two groups according to the Keith-Wagener classification. Group 1 comprised 36 patients with grade I HR and group 2 36 patients with grade II HR Thirty-six normotensive healthy subjects matched for age, sex, and body mass index were selected for the control group. RESULTS: The level of ferritin in group 2 was significantly higher than in group 1 (92.9+/-31.8 vs. 77.8+/-23.7 ng/ml, p=0.027) and the normotensive control group (92.9+/-31.8 vs. 59.9+/-19.2 ng/ml, p=0.001). It was also higher in group 2 than in the control group (77.8+/-23.7 vs. 59.9+/-19.2 ng/ml, p=0.018). Ferritin level also showed positive correlation with the degree of HR in the hypertensive group (r=0.31, p=0.026). CONCLUSIONS: This study suggests that there is a relationship between HR and ferritin level, which may be associated with an increased level of oxidative stress.

Effect of intrathecal FK506 administration on intraorbital optic nerve crush: an ultrastructural study.

OBJECTIVE: Trauma to the optic nerve caused by fractures of the midface and (or) skull base has been simulated by an optic nerve crush injury model. Because the intraorbital segment of the optic nerve is surrounded by subarachnoidal cerebrospinal fluid and dura mater, we aimed to study the influence of intrathecal tacrolimus (FK506) administration after optic nerve crush injury and to determine its role in optic nerve protection or sparing after injury. STUDY DESIGN: Experimental study. PARTICIPANTS: All optic nerves of the animals were included in the study. METHODS: A total of 48 female Wistar rats were randomly divided into 4 groups (control, sham operated, FK506 treated, and vehicle treated). In vehicle- and FK506-treated groups, intrathecal catheter implantation and crush injury to the intraorbital part of the optic nerve were performed and then the animals were treated intrathecally. The optic nerve samples were harvested on the 30th postoperative day. Optic nerve appearances were analyzed qualitatively. RESULTS: Light and electron microscopic evaluations revealed that numerous damaged myelin residues were present in the vehicle-treated group, whereas fibres of the optic nerve showed a well-shaped appearance in the FK506-treated group. CONCLUSION: We propose that such an intrathecal administration route and small-dose regimen should be used to obtain lesser immunosuppression and neurotoxicity and higher protection or sparing after injury.

Assessment of an effective visual field testing strategy for a normal pediatric population.

AIM: To investigate which visual field testing strategy yields more reliable and tolerable field analysis in a normal pediatric population. MATERIAL AND METHODS: 68 healthy children aged 6-13 years with no ocular or systemic diseases were included in the study. One randomly selected eye of each child underwent standard achromatic visual field analysis using a Model 750 Humphrey Field Analyzer II (Carl Zeiss Meditec, Dublin, Calif., USA). We evaluated the reliability criteria (false negative, false positive and fixation loss scores) and the duration of the visual field tests performed by Fastpac (with stimulus sizes III and V, respectively) and SITA Fast with stimulus size III. Moreover, subjects underwent Goldmann perimetry testing with stimulus V. Ability to complete the perimetry tests was also scored. Perimetric analysis was stopped before the end if signs of fatigue appeared. Mean sensitivity, mean defect and pattern standard deviation were recorded for automated tests. RESULTS: All subjects but 8 successfully completed each of four tests. The mean duration of the tests was 4.23, 5.46, 6.35 and 11.06 min for SITA Fast with stimulus size III, Fastpac with stimulus size V, Size III and Goldmann perimetry, respectively (p < 0.001). Both false-negative and false-positive test scores were found to be significantly lower for SITA Fast with stimulus size III compared to the other automated tests (p < 0.01). Children older than 8 years (n = 35) achieved significantly higher test reliability scores (p < 0.01). CONCLUSION: As early detection of structural and functional visual abnormalities may be of utmost importance in the pediatric population considering many potentially serious neurological and ocular problems met with, accurate and reproducible visual field testing is vital. To achieve this goal, visual field testing with SITA Fast algorithm seemed to be a promising strategy for a pediatric population in a typical clinical setting.

Effect of laser spot diameter on the reproducibility of visual field analysis in diabetic patients with upper temporal retinal vein occlusion.

AIM: To evaluate the effect of the laser spot diameter on the reproducibility of the visual field analysis in diabetic patients with upper temporal retinal vein occlusion. MATERIAL AND METHODS: Thirty-six eyes of 36 consecutive type-2 diabetes mellitus patients with upper temporal retinal vein occlusion who required sectoral retinal photocoagulation (SRP) treatment were enrolled for the study. Patients with a history of previous retinal laser photocoagulation, significant lenticular opacities and those whose perimetric test reliability criteria were low (fixation loss >20% and false-positive or false-negative responses >33%) were excluded from the study. SRP was applied to the upper temporal retinal quadrant. Nineteen eyes received SRP treatment with 500-mum laser spots (group 1) while the rest of the eyes (n = 17) received SRP with 300-microm laser spots (group 2). Patients underwent five consecutive visual field analyses, each on a different day during a 2-week period, both before and 6 weeks after SRP. The Humphrey field analyzer central 30-2 threshold test using SITA Standard strategy was applied for visual field testing. RESULTS: The mean age of the patients in groups 1 and 2 were 58.6 +/- 6.7 and 59.1 +/- 7.1 years, respectively (p > 0.05). Pre-SRP mean retinal sensitivities of the lower nasal quadrant in groups 1 and 2 were not different statistically (p > 0.05). Post-SRP mean retinal sensitivity of the lower nasal quadrant was significantly higher in group 2 than group 1. Moreover, mean defect has been found to be lower in group 2 (p < 0.05). The coefficient of variation for pre-SRP retinal sensitivity measurements were 7.9 and 7.6% for groups 1 and 2, respectively (p > 0.05). The coefficient of variation for post-SRP retinal sensitivity measurements were 3.8 and 2.1% for groups 1 and 2, respectively (p < 0.05). CONCLUSION: SRP treatment with 300-microm diameter laser spots may yield more reproducible visual field data than that with 500-mum diameter laser spots. Moreover, the improvement in the retinal sensitivity of the patients with branch retinal vein occlusion is more marked in case where 300-microm laser spots are used.

Corneal protein nitration in experimental uveitis.

Increased expression of inducible nitric oxide synthase (NOS-2) in inflammatory diseases like uveitis suggests that it contributes to the observed pathological state. The aim of this study was to evaluate corneal expression of NOS-2 and corneal protein nitration in a rat model of uveitis. A single injection of intravitreal lipopolysaccharide was used to induce uveitis. Corneal proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and visualized by Coomassie blue staining. Expression of NOS-2 and nitrotyrosine (NO(2)Tyr) formation were determined via immunohistochemistry and Western blot analysis. Total nitrate/nitrite levels in the vitreous were measured by spectral analysis via the Griess reagent. Immunohistochemical analysis revealed increased corneal NOS-2 and NO(2)Tyr immunoreactivity in rats with uveitis compared with controls. NOS-2 and NO(2)Tyr immunoreactivity was observed in and around basal cells in the corneal epithelium. Western blot analysis of corneal lysates showed multiple nitrated protein bands in uveitic rats. Spectrophotometric measurement of total nitrate/nitrite levels in the vitreous affirmed significantly increased levels of nitric oxide generation in uveitis (126 +/-2.63 microM/mg protein) compared with controls (65 +/-6.57 microM/mg protein). The presented data suggests that extensive formation of protein nitration and reactive nitrogen species in the cornea contributes to tissue destruction in uveitis. Hence, selective inhibition of NOS-2 may prevent long-term complications and lead to an improvement in the management of uveitis.

Interocular differences in optic nerve head topography of the subjects with unilateral peripapillary myelinated nerve fibers.

PURPOSE: To determine the interocular differences in optic nerve head topography of the subjects with unilateral peripapillary myelinated nerve fibers. MATERIALS AND METHODS: A total of 21 healthy subjects with unilateral peripapillary myelinated nerve fibers were included into the study. Patients had no ocular disease except refractive disorders. Optic nerve head topographic analyses of both eyes of each subject were performed using a confocal scanning laser ophthalmoscope, HRT-II (Heidelberg Retina Tomography II, version 1.6). The disc area, topography standard deviation, and a total of 12 topographic parameters were calculated by the HRT-II. RESULTS: The mean age of the subjects was 28.3+/-3.4 years. The mean refractive error of the eyes with and without myelinated nerve fibers were -3.56+/-1.73 D and -0.98+/-0.66 D, respectively (P<0.05). There were no significant interocular differences in the disc area of the eyes with and without peripapillary myelinated nerve fibers (P>0.05). Eyes with peripapillary myelinated nerve fibers were found to have significantly less "neuroretinal rim area" and "neuroretinal rim area-to-disc area ratio" than those eyes with no myelination (P<0.05 for both). All other parameters were found not to reveal any significant interocular differences (P>0.05 for all of them). Sectorial analysis of the parameters including neuroretinal rim area and neuroretinal rim area-to-disc area ratio did not reveal any significant differences between the groups (P>0.05). CONCLUSIONS: Neuroretinal rim area and rim area-to-disc area ratio of the eyes with peripapillary myelinated nerve fibers were found to be significantly less than that of the fellow eyes with no myelination. This should be taken into consideration when monitoring glaucoma suspects with peripapillary myelinated nerve fibers.

Recurrence of keratoconus in two corneal grafts after penetrating keratoplasty.

PURPOSE: To report the recurrence of postkeratoplasty keratoconus in 2 corneal grafts harvested from the same donor. DESIGN: Interventional case reports. METHODS: A 21-year-old-man with advanced keratoconus in his right eye and a 28-year-old-woman with corneal leucoma in her right eye underwent penetrating keratoplasty with 2 grafts coming from the same donor. Approximately 1.5 years after grafting, corneal irregularity and astigmatism caused visual acuities of the patients to decrease to counting fingers. Clinical findings and corneal topography suggested the recurrence of keratoconus. A repeat keratoplasty was performed in both patients. RESULTS: Histopathology of the excised corneal grafts was consistent with keratoconus and confirmed the preoperative diagnosis. CONCLUSIONS: Recurrence of keratoconus in a patient who had no preexisting keratoconus and in 2 corneal grafts coming from the same donor suggested transmission of the disorder from the donor instead of true recurrence.

Outbreak of toxic anterior segment syndrome associated with glutaraldehyde after cataract surgery.

PURPOSE: To present clinical findings of a cluster of cases of toxic anterior segment syndrome (TASS) after uneventful phacoemulsification cataract surgery. SETTING: Department of Ophthalmology, Akdeniz University, Antalya, Turkey. METHODS: Six eyes of 6 patients developed TASS after uneventful phacoemulsification cataract surgery with implantation of a 3-piece acrylic IOL performed by 2 ophthalmologists on the same day. Clinical findings included corneal edema, Descemet's membrane folds, anterior chamber reaction, fibrin formation, and irregular, dilated, and unreactive pupils. RESULTS: Glutaraldehyde 2% solution was used inadvertently by the operating room staff who cleaned and sterilized reusable ocular instruments before autoclaving. None of the affected corneas improved. Additional surgical procedures were required and included penetrating keratoplasty, trabeculectomy, and glaucoma tube implantation. CONCLUSIONS: Glutaraldehyde in concentrations generally used for cold sterilization is highly toxic to the corneal endothelium. The operating room staff involved in sterilizing instruments should be well educated about and careful to follow the protocols to properly clean and sterilize reusable ocular instruments.

Brinzolamide 1% versus apraclonidine 0.5% to prevent intraocular pressure elevation after neodymium:YAG laser posterior capsulotomy.

PURPOSE: To compare the efficacy of brinzolamide 1% with that of apraclonidine 0.5% in preventing intraocular pressure (IOP) rise after neodymium:YAG (Nd:YAG) laser posterior capsulotomy. SETTING: Department of Ophthalmology, Akdeniz University, Antalya, Turkey. METHODS: One hundred fifteen patients who had Nd:YAG laser posterior capsulotomy for posterior capsule opacification were prospectively randomized to receive brinzolamide 1% (57 patients) or apraclonidine 0.5% (58 patients) approximately 1 hour before laser surgery. A masked observer measured IOP by Goldmann applanation tonometry before treatment and after treatment at 1, 2, and 3 hours and 7 days. RESULTS: The mean IOP changes from baseline were not statistically different between the study groups at 1, 2, and 3 hours and 7 days (P =.109, P = .764, P =.275, and P =.879, respectively). The incidence of IOP elevation of 5 mm Hg or higher was 12.2% (7 of 57 eyes) in the brinzolamide group and 10.3% (6 of 58 eyes) in the apraclonidine group (P = .743); IOP elevations of 10 mm Hg and greater occurred in 3.5% (2 of 57 eyes) and 1.7% (1 of 58 eyes) (P = .618), respectively. There were no IOP elevations greater than 20 mm Hg in either group. CONCLUSION: Brinzolamide 1% and apraclonidine 0.5% given prophylactically before Nd:YAG laser capsulotomy were effective in preventing IOP spikes after treatment.

Phacoemulsification with topical anesthesia: Resident experience.

PURPOSE: To compare the intraoperative and postoperative complications and outcomes of phacoemulsification performed by residents using topical and retrobulbar anesthesia. SETTING: Two university ophthalmology departments. METHODS: One hundred fifty phacoemulsification procedures were performed by 3 residents who used retrobulbar anesthesia (retrobulbar group), and 146 phacoemulsification procedures were performed by another 3 residents who used topical anesthesia and who had no experience with retrobulbar or peribulbar anesthesia (topical group). Case notes were prospectively compared. The data analyzed included the ocular history, intraoperative and postoperative complications, and final best spectacle-corrected visual acuity (BSCVA). RESULTS: There were no differences between the 2 groups in complication rates. Anterior capsule tears occurred in 8 eyes (5.3%) in the retrobulbar group and 7 eyes (4.7%) in topical group. Capsulorhexis was continuous but not curvilinear in 14 eyes (9.3%) and 12 eyes (8.2%), respectively. Capsulorhexis tear or posterior capsule rupture that necessitated conversion to extracapsular cataract extraction occurred in 3 eyes (2.0%) in the retrobulbar group and in 1 eye (0.6%) in the topical group. Posterior capsule rupture with vitreous loss occurred in 10 eyes (6.6%) and 9 eyes (6.1%), respectively. Loss of lens fragments in the vitreous cavity occurred in 3 eyes (2.0%) and 4 eyes (2.7%), respectively. The 63 postoperative complications (41 eyes [27.3%], retrobulbar group; 22 eyes [15.0%], topical group) included cystoid macular edema, intraocular lens decentration, endophthalmitis, bullous keratopathy, transient intraocular pressure elevation, temporary corneal edema, and vitreous hemorrhage. Some cases had more than 1 complication. The BSCVA, including in eyes with preexisting ocular pathology, was 20/40 or better in 86.7% in the retrobulbar group and 84.9% in the topical group. CONCLUSION: When supervised and in selected patients, residents who have no retrobulbar or peribulbar anesthesia experience can safely perform phacoemulsification using topical anesthesia.

Transmission electron microscopy and autofluorescence findings in the cornea of diabetic rats treated with aminoguanidine.

BACKGROUND: The accumulation of advanced glycation end products (AGEs) has been implicated in the pathogenesis of diabetic keratopathy. The present study was aimed to understand if aminoguanidine (AG), an AGE inhibitor, was protective against the development of corneal complications in a diabetic rat model. METHODS: Wistar rats were divided into three experimental groups: control, diabetic, and AG-treated diabetic. Diabetes was induced in rats via a single intraperitoneal injection (60 mg/kg) of streptozocin (STZ) and AG was administered in drinking water at a dose of 1 g/L. All animals were sacrificed at the end of 10 weeks and corneas from diabetic and nondiabetic rats were analyzed via transmission electron microscopy (TEM). Corneal autofluorescence measurements were also performed in all experimental groups. RESULTS: Electron microscopic evaluation revealed that aminoguanidine treatment in diabetic rats prevented the formation of intracellular spaces between neighbouring cells in the superficial corneal epithelium. Hyperglycemia-induced degeneration of intracellular organelles and formation of cytoplasmic vacuoles in the corneal stroma was also prevented with the treatment of AG. Corneal autofluorescence detected in the diabetic group (5.98 +/- 2.17 Fi/mg protein) was found to be significantly greater than the control (3.92 +/- 0.56 Fi/mg protein) and the AG-treated diabetic group (4.18 +/- 0.59 Fi/mg protein) (p < 0.05). INTERPRETATION: The presented data provide evidence that AG is preventive against corneal alterations in experimental diabetes.