A new method based on deep learning and image processing for detection of strabismus with the Hirschberg test.

Strabismus is a condition in which one or both eyes do not work in parallel or in harmony. People with strabismus have one eye looking straight ahead while the other eye looks inwards, outwards, upwards or downwards. This condition can affect both eyes. Strabismus is a common eye condition that affects about 4 % of the world's population. Tests such as Hirschberg, Cover and Krimsky are used to detect strabismus. In the Hirschberg test, a light source is held at a distance of 50 cm so that it falls on the centre of each eye. The horizontal and vertical distance between the centre of gravity of the light reflected from the cornea and the centre of the pupil indicates the degree of strabismus. In this study, deep learning and image processing algorithms are used to detect the eye, corneal reflection, iris and pupil on a patient's facial image. Based on the Hirschberg test, the horizontal and vertical shifts for both eyes were measured to determine the patient's degree of strabismus. In this way, the Hirschberg test used in strabismus screening was performed automatically by software. The correct detection of the pupil and the light reflected from the cornea by the algorithm means that the eye has been measured correctly. The software was tested on the facial images of 88 strabismic patients of different sexes and ages. 91 % of the 88 patients, or 80 patients, had their left eye measured correctly. 90 % of the 88 patients, or 79 patients, had their right eye measured correctly. The results for each eye obtained from the correct measurements were found to have an error of maximum ± 2°. This error is due to the fact that a real eye is in three-dimensional space, while the digital eye image is in two-dimensional space, and was only observed in the test results of some patients. This algorithm can be tested on patients of all ages and is not affected by morphological differences in the patients' faces. Successful results have been observed experimentally that this newly proposed method can be used in strabismus screening.

Plasma and aqueous levels of subfatin, preptin and betatrophin in patients with diabetic retinopathy.

AIM: To examine subfatin, preptin and betatrophin levels in plasma and aqueous in patients with diabetes mellitus (DM) (with and without retinopathy). MATERIAL AND METHOD: Sixty patients, who were similar in terms of age and gender, and were scheduled for operation due to cataract, were included in the study. The patients were divided into three groups as Group C (20 weeks without diabetes and comorbidity), Group DM (20 patients with DM but no retinopathy) and Group DR (20 patients with diabetic retinopathy). The preoperative body mass index (BMI), fasting plasma glucose, HbA1c, lipid profile levels of all patients in the groups were examined. Blood samples were also taken for plasma subfatin, preptin and betatrophin levels. At the beginning of the cataract surgery, 0.1 ml of aqueous fluid was taken from the anterior chamber. Plasma and aqueous subfatin, preptin and betatrophin levels were analyzed by ELISA (enzyme-linked immunosorbent assays) method. RESULTS: In our study results, there was a significant difference in BMI, fasting plasma glucose and hemoglobin A1c levels (p < 0.05 for all parameters). Plasma and aqueous subfatin levels were higher in Group DR compared to Group C (p < 0.001, p = 0.036, respectively). Plasma and aqueous preptin levels were higher in group DR and group DM than in group C (p = 0.001, p = 0.002, p < 0.001, p = 0.001, respectively). Plasma and aqueous betatrophin levels were higher in Group DR compared to group C (p = 0.001, p = 0.010, respectively). CONCLUSION: Subfatin, preptin and betatrophin molecules may have an important role in the pathogenesis of diabetic retinopathy.

Evaluation of central corneal epithelial thickness with anterior segment OCT in patients with type 2 diabetes mellitus.

BACKGROUND: This study aimed to evaluate the central corneal thickness (CCT) and central corneal epithelial thickness (CCET) in patients with Type 2 diabetes mellitus (DM), and the effect of the duration of diabetes, the degree of diabetic retinopathy (DR), and HbA1c level. METHODS: CCT and CCET values of 72 patients diagnosed with type 2 DM and 72 healthy individuals were measured by anterior segment optical coherence tomography. The eye tear function was evaluated with the Tear Break-up Time test (TBUT) and the Schirmer test. From the results of fundus examination, the diabetic patients were grouped as those without DR, non-proliferative DR, and proliferative DR. The disease duration and the HbA1c levels were recorded. RESULTS: In the diabetic patients, the mean CCT was determined to be thicker (p = 0.025), the CCET was thinner (p = 0.003), and the TBUT and Schirmer values were lower (p <0.001, p <0.001, respectively). The duration of diabetes and the HbA1c level was not found to have any statistically significant effect on these parameters (p >0.05). The presence of retinopathy had no significant effect on CCT, TBUT, and Schirmer values. The CCET was determined to be thinner in patients with retinopathy (p <0.001). CONCLUSIONS: As the corneal epithelial thickness is reduced in patients with advanced diabetic retinopathy, corneal epithelial pathologies can be seen more often. Therefore, early and effective treatment can be started by taking into consideration the complications which may develop associated with the corneal epithelium following surgical procedures, especially those applied to the cornea.

A rare cause of pediatric oculomotor nerve palsy: neurobrucellosis.

Neurobrucellosis is a significant complication of brucella, which is seen more rarely in children than in adults. As there are no specific symptoms, it may be confused with several diseases which involve the nervous system. Although various cranial nerves can be affected in neurobrucellosis, oculomotor nerve involvement is extremely rare. The case is here presented of a 13-year-old patient who presented at the polyclinic with complaints of double vision and left eyelid droop. The diagnosis of neurobrucellosis was made from the determination of brucella antigens in the serum and cerebrospinal fluid, and following treatment, the patient recovered without sequelae. The aim of this case presentation was to emphasise that a reason for oculomotor nerve palsy in the paediatric age group, especially in regions where brucella is endemic, could be neurobrucellosis.

Automated Diabetic Retinopathy Detection Using Horizontal and Vertical Patch Division-Based Pre-Trained DenseNET with Digital Fundus Images.

Diabetic retinopathy (DR) is a common complication of diabetes that can lead to progressive vision loss. Regular surveillance with fundal photography, early diagnosis, and prompt intervention are paramount to reducing the incidence of DR-induced vision loss. However, manual interpretation of fundal photographs is subject to human error. In this study, a new method based on horizontal and vertical patch division was proposed for the automated classification of DR images on fundal photographs. The novel sides of this study are given as follows. We proposed a new non-fixed-size patch division model to obtain high classification results and collected a new fundus image dataset. Moreover, two datasets are used to test the model: a newly collected three-class (normal, non-proliferative DR, and proliferative DR) dataset comprising 2355 DR images and the established open-access five-class Asia Pacific Tele-Ophthalmology Society (APTOS) 2019 dataset comprising 3662 images. Two analysis scenarios, Case 1 and Case 2, with three (normal, non-proliferative DR, and proliferative DR) and five classes (normal, mild DR, moderate DR, severe DR, and proliferative DR), respectively, were derived from the APTOS 2019 dataset. These datasets and these cases have been used to demonstrate the general classification performance of our proposal. By applying transfer learning, the last fully connected and global average pooling layers of the DenseNet201 architecture were used to extract deep features from input DR images and each of the eight subdivided horizontal and vertical patches. The most discriminative features are then selected using neighborhood component analysis. These were fed as input to a standard shallow cubic support vector machine for classification. Our new DR dataset obtained 94.06% and 91.55% accuracy values for three-class classification with 80:20 hold-out validation and 10-fold cross-validation, respectively. As can be seen from steps of the proposed model, a new patch-based deep-feature engineering model has been proposed. The proposed deep-feature engineering model is a cognitive model, since it uses efficient methods in each phase. Similar excellent results were seen for three-class classification with the Case 1 dataset. In addition, the model attained 87.43% and 84.90% five-class classification accuracy rates using 80:20 hold-out validation and 10-fold cross-validation, respectively, on the Case 2 dataset, which outperformed prior DR classification studies based on the five-class APTOS 2019 dataset. Our model attained about >2% classification results compared to others. These findings demonstrate the accuracy and robustness of the proposed model for classification of DR images.

Interleukin 18, soluble cluster of differentiation 40, platelet factor 4 variant 1, and neutrophil gelatinase-associated lipocalin can be used as biomarkers to aid activity and diagnosis in ocular Behçet's disease.

PURPOSE: The molecules human interleukin (IL-18), the soluble cluster of differentiation (sCD40), platelet factor 4 variant 1 (PF4V1), and neutrophil gelatinase-associated lipocalin (NGAL) are all markers of inflammation in biological systems and are linked to prognosis in several inflammatory diseases as well. Since there is no study in which the above-mentioned molecules are studied together in ocular Behçet's disease (OBD), the aim of this study is to reveal whether these molecules are activity markers in active (OABD) and inactive (OIBD) disease. METHODS: 30 OABD and 30 OIBD and 30 healthy individuals were included in the study. IL-18, sCD40, PF4V1, and NGAL molecules were studied in blood samples by the ELISA method. RESULTS: When OABD and OIBD were compared to healthy individuals, the levels of IL-18, sCD40, PF4V1, and NGAL molecules were found to be statistically significant. These values were even more significantly higher in patients with OABD. CONCLUSION: When ROC values of IL-18, sCD40, PF4V1, and NGAL are evaluated, it is clear that these four molecules can be used as biomarkers to aid activity and diagnosis in OBD.

Plasma and aqueous levels of alarin and adipsin in patients with and without diabetic retinopathy.

BACKROUND: Diabetic retinopathy is a disease seen with microvascular complications as a result of hyperglycemia and insulin resistance. Alarin and Adipsin are molecules with a role in energy and glucose metabolism. The aim of this study was to determine plasma and aqueous levels of Alarin and Adipsin in patients with and without diabetic retinopathy to evaluate their potential roles in diabetic retinopathy. METHODS: The study included one eye from each of 20 cataract patients without diabetes (C), 20 cataract patients with diabetes and without diabetic retinopathy (DM + C), and 20 cataract patients with diabetes and diabetic retinopathy (DR + C). Plasma and aqueous humour samples were taken from all patients during the cataract operation. Alarin and Adipsin levels were examined with the enzyme-linked immunosorbent assay (ELISA) method. RESULTS: Both plasma and aqueous Alarin levels were significantly higher in the patients with diabetic retinopathy than in the control group (p < 0.001, p = 0.006). Adipsin levels were found to be significantly higher in plasma in the control group than in the DR + C group and significantly higher in aqueous in the DR + C group than in the control group (p < 0.001, p < 0.001). CONCLUSION: These findings suggest that Alarin and Adipsin may play important role in diabetic retinopathy.

Plasma and aqueous humor levels of adiponutrin and pannexin 1 in patients with and without diabetic retinopathy.

AIM: To evaluate plasma and aqueous levels of adiponutrin and pannexin 1 in patients with and without diabetic retinopathy. METHODS: The study included three age and gender-matched groups of 20 cataract patients with no diabetes or additional disease (Group C), 20 cataract patients with diabetes and no retinopathy (Group DM+C), and 20 cataract patients with diabetic retinopathy (Group DR+C). All the patients were examined with respect to body mass index (BMI), fasting plasma glucose, hemoglobin A1c (HbA1c), and lipid profile. Phacoemulsification and intraocular lens (Phaco+IOL) implantation were performed to all patients in all the groups, and aqueous samples were taken during the operation. The plasma and aqueous adiponutrin and pannexin 1 levels were analyzed using enzyme-linked immunosorbent assays. RESULTS: A statistically significant difference was determined between the groups with respect to BMI, fasting plasma glucose, and HbA1c levels (P<0.05 for all parameters tested). The plasma adiponutrin levels of Group DR+C were statistically significantly lower than those of Group C and Group DM+C (P<0.001, P=0.004). No statistically significant difference was determined in the aqueous adiponutrin levels in three groups. The plasma pannexin 1 levels of Groups DM+C and DR+C were statistically significantly lower than those of Group C (both P=0.001). The aqueous pannexin 1 levels of Group DR+C were statistically significantly higher than those of Group C and Group DM+C (P=0.001, P<0.001). CONCLUSION: Adiponutrin and pannexin 1, which play an important role in the pathophysiology of diabetes and obesity, and have a regulatory role in hyperglycemia and insulin resistance. The measurement of adiponutrin and pannexin 1 levels may support clinicians in determining the risk of DR development.

How are central foveal and choroidal thickness affected in patients with mild COVID-19 infection?

The aim of this study was to evaluate the effects of  COVID-19 on central foveal and choroidal thicknesses. Thirty-two patients with a positive SARS-CoV-2 PCR test who received outpatient treatment within the previous two months and 32 healthy controls were included in the study. Patients requiring hospitalization due to COVID-19 as well as the patients who received either intensive care support and/or antiplatelet therapy, smokers, or patients with systemic or ocular diseases were excluded from the study. After full ophthalmological examination, central foveal and choroidal thicknesses were evaluated by using optical coherence tomography. Statistical analysis of the study data demonstrated no significant difference between the groups in terms of age or gender (p>0.05). There was also no statistically significant difference between the groups in terms of central foveal thickness, central choroidal thickness, or nasal 500, nasal 1500, temporal 500, or temporal 500-micron distances (p>0.05 for all parameters). Choroidal and retinal thicknesses were not affected in patients with recent mild COVID 19 without comorbidities.

Effects of Topical Carbonic Anhydrase Inhibitors on the Olfactory Sense.

OBJECTIVES: The sense of smell plays an important role in daily life. Olfactory impairment can significantly affect an individual's quality of life. Topical carbonic anhydrase inhibitors are commonly used to treat elevated intraocular pressure (IOP). One potential side effect of these drugs is a loss of the sense of smell. This study is an examination of changes in olfactory function in patients who used dorzolamide and brinzolamide to control IOP after a laser capsulotomy. METHODS: A total of 60 patients with posterior capsule opacification were included in the study. Sniffin' Sticks (Burghart Messtechnik GmbH, Wedel, Germany) were used to evaluate patient olfactory sensitivity before starting the topical treatment and after 1 week of treatment. RESULTS: No statistically significant decrease in olfactory performance was observed in users of either brinzolamide or dorzolamide (p=0.705, p=0.405 respectively). CONCLUSION: No negative effect on the sense of smell was determined after 7 days of topical application of a carbonic anhydrase enzyme inhibitor to the eye in patients with no previous anosmia.

Serum Cystatin C Concentrations in Patients with Graves' Ophthalmopathy.

PURPOSE: To evaluate the concentration of serum cystatin C (CysC) in patients with Graves' ophthalmopathy (GO) and the usability of the serum CysC concentrations in the follow-up of the disease. METHODS: Thirty patients with GO and 30 healthy age-matched volunteers were included in this cross-sectional study. GO was diagnosed based on the European Group on Graves' Orbitopathy consensus. Serum thyroid-stimulating hormone, free triiodothyronine, free thyroxine, and CysC concentrations were measured in the participants. The serum CysC concentrations were compared between patients with GO and controls. Patients with GO were subdivided into hyperthyroid and euthyroid patients, and their serum CysC concentrations were compared. In addition, the CysC concentrations in hyperthyroid and euthyroid patients with GO were compared separately with those of healthy subjects. Kruskal-Wallis test and Student's t-test were used for statistical evaluation. RESULTS: The mean serum CysC concentrations in GO patients and controls were 1.04 ± 0.36 and 0.74 ± 0.09 mg/L, respectively. There was a statistically significant difference in the serum CysC concentrations between patients with GO and control subjects (p < 0.001). Fifteen patients had hyperthyroid status, and 15 patients had euthyroid status. The mean serum CysC concentrations in hyperthyroid and euthyroid patients with GO were 1.35 ± 0.22 and 0.72 ± 0.13 mg/L, respectively. Serum CysC concentrations were significantly higher in hyperthyroid patients than in euthyroid patients (p = 0.001). In addition, hyperthyroid patients had significantly higher serum CysC concentrations than healthy subjects. Among patients with GO, 21 and nine had mild and moderate-to-severe GO, respectively. Active and inactive GO were observed in eight and 22 patients, respectively. CONCLUSIONS: The serum CysC concentrations in hyperthyroid patients were higher than those in healthy subjects. Moreover, hyperthyroid patients had higher serum CysC concentrations than euthyroid patients. Further studies with a larger sample size are needed to confirm these results.

Iodine-Induced Retinopathy: A Case Report

Potassium iodide is used as an iodine supplement in salt as part of a national program in Turkey. An overdose of iodine has a toxic effect on the retinal pigment epithelium and photoreceptors. The case presented here is a patient who developed retinopathy following consumption of an excessive dose of iodine.

Importance of Müller Cells.

Müller cells (MCs) are the most common glial cell found in the human retina. MCs have an important role in architectural and metabolic functions in the retina. Additionally, there has been consideration that MC dysfunction might contribute to the pathogenesis of some retinal diseases, such as proliferative vitreoretinopathy, diabetic retinopathy, macular edema, retinal vein occlusion, macular telangiectasia type 2, age-related macular degeneration, retinal degeneration, hepatic and methanol-induced retinopathy, and glaucoma. This review is a summary of the functions of MCs and a discussion of the importance of these glial cells.

A Glossary for ''Pseudo'' Conditions in Ophthalmology.

The term "pseudo'' refers to ''lying, false, fake, simulation, imitation or spurious.'' In ophthalmological literature, there are many diseases/conditions/signs/phenomena that are considered as "pseudo." A literature search was conducted on the Medical Subject Headings website, and the keywords that were searched in the title and abstract were as follows: (pseudo-), (fake), (false), (mimicker), (simulator), (masquerade), AND (condition) AND(causes) AND (ophthalmology)OR (eye) OR (ocular) OR (ophthalmic) OR (cornea) OR (retina) OR (strabismus) OR (glaucoma). The search was restricted to English language. The major databases such as PubMed, Medline, Scopus, Google Scholar, OVID, EBSCO, and Cochrane Library were searched or investigated for information. The objective of this review is to summarize common ''pseudo'' conditions in ophthalmology and their respective common causes. We believe that the knowledge of these pseudo-conditions will provide significant benefits in the differential diagnosis of various ophthalmic disorders.

Pediatric Canaliculitis: A Case Report

Canaliculitis is a rare disease that relapses when not properly diagnosed and treated. It usually occurs in middle-age and advanced age. It is extremely rare in children and infants. A healthy 12-year-old girl presented with lower eyelid swelling and watery discharge in her right eye. During the last 2 years, the patient had been examined several times for the same complaints but there was no improvement despite treatment. Examination showed that the lower punctum had a pouting punctum appearance, and applying pressure to the lacrimal sac area resulted in purulent discharge. Lavage showed that the lacrimal passage was patent. In light of these clinical findings, the patient was diagnosed with canaliculitis. Punctoplasty with surgical curettage of the dacryoliths were performed. After the surgical procedure, a topical antibiotic was prescribed. Histopathological examination of the dacryoliths revealed that the infective cause was Actinomyces. No recurrence or complications were observed during 12 months follow-up.

The effect on wound healing of pazopanib and bevacizumab compared with corticosteroid in experimental glaucoma filtration surgery.

AIM: To compare the effects of bevacizumab and pazopanib with corticosteroids on wound healing after trabeculectomy. METHODS: In the study, 35 New Zealand white rabbits were randomly divided into five groups. Apart from the first group, limbus-based trabeculectomy was performed for the eyes of rabbits. No postoperative treatment was administered for group I. Topically administered saline, prednisolone acetate (1%), bevacizumab 5 mg/mL, pazopanib 5 mg/mL for group II, III, IV and V respectively were applied for groups 6h daily for 28d. On day 28 of the experiment, eyes were enucleated and histologically and immunohistochemically analyzed. RESULTS: The fibroblast counts of groups IV and V were determined to be lower than those of groups II and III (P<0.05). In the mononuclear cell (MNC) count evaluation, no statistically significant difference was determined between the treatment groups (P>0.05). The immunohistochemical staining intensity of fibroblast growth factor ß (FGF-ß) and vascular endothelial growth factor (VEGF) was determined to be lower in groups IV and V than in groups II and III (P<0.05). No statistically significant difference was determined between groups IV and V in respect of fibroblast count, MNC count, FGF-ß and VEGF staining intensity (P>0.05). The platelet derived growth factor ß (PDGF-ß) intensity was lower in group V than in groups II, III and IV (P<0.05). While the PDGF-ß staining intensity was significantly lower in group IV than in group II, the difference compared with group III was not statistically significant (P>0.05). CONCLUSION: Bevacizumab and pazopanib might be good alternatives of corticosteroid treatment on delaying wound healing in glaucoma surgery.

QT interval dispersion in the patients with central serous chorioretinopathy.

AIM: To evaluate QT dispersion (QTD) in patients with central serous chorioretinopathy (CSC). METHODS: This clinical, comperative, case-control study included 30 patients with CSC at acute phase (Group 1) and 30 age- and sex-matched healthy subjects (Group 2, the control group). From all subjects, a 12-lead surface electrocardiography was obtained. The heart rate (HR), QT maximum (QTmax), QT minimum (QTmin), QT corrected (QTc), QTD and Tmean were manually measured and analyzed. Student's t-test and Pearson's method of correlation were used for statistical analysis. RESULTS: The patient and control groups were matched for age, smoking status (rate and duration) and gender. There were no significant differences with regard to these among the groups (P>0.05). The participants included 19 men (63.3%) and 11 women (36.7%) in Group 1, 20 men (66.7%) and 10 women (33.3%) in Group 2. QTmax, QTD and QTc were significantly higher than those of healthy controls (P<0.001 for QTmax, P=0.01 for QTD and P=0.001 for QTc). QTmin, Tmean and HR did not differ significantly between the study groups (P=0.28 for QTmin, P=0.56 for Tmean and P>0.05 for HR). No significant correlation was found between duration of the disorder and QTD values (r=0.13, P>0.05). CONCLUSION: These findings suggest that CSC may be associated with an increase in QTD and that the patients might be at risk for ventricular arrhythmia.

Topical infliximab for the suppression of wound healing following experimental glaucoma filtration surgery.

BACKGROUND: The purpose of this work was to look into the effects of infliximab on wound healing in experimental glaucoma filtration surgery and to compare the antifibrotic effects of this agent to that of mitomycin-C (MMC). METHODS: Twenty-eight male New Zealand White rabbits were randomly assigned to four groups, each including seven rabbits: control group, sham group, MMC group, and infliximab group. The rabbits in the control group were not operated on and did not receive any treatment. The rabbits in the sham group underwent trabeculectomy and had one drop of saline instilled four times a day for 14 days. The rabbits in the MMC treatment group underwent trabeculectomy, and a sponge soaked in 0.4 mg/mL MMC was applied intraoperatively to the scleral surgical site for three minutes. The rabbits in the infliximab treatment group underwent trabeculectomy and one drop of 10 mg/mL infliximab was instilled four times a day for 14 days after surgery. On day 14 of the experiment, the operated and control eyes were enucleated and histologically and immunohistochemically analyzed. RESULTS: The mean fibroblast and mononuclear cell (MNC) numbers and the mean immunostaining intensities of transforming growth factor-ß (TGF-ß), fibroblast growth factor-ß (FGF-ß), and platelet-derived growth factor (PDGF) in the sham group were higher than those of the control group (P<0.01). The mean fibroblast and MNC numbers and the mean immunostaining intensities of TGF-ß, FGF-ß, and PDGF in the MMC and infliximab groups were statistically significantly lower than those of the sham group (P<0.01). The mean fibroblast and MNC numbers and the mean TGF-ß, FGF-ß, and PDGF immunostaining intensities of the MMC and infliximab groups were similar (P>0.05). CONCLUSION: Our study suggests that topical infliximab effectively suppresses the subconjunctival wound healing response after experimental glaucoma filtration surgery, reducing the MNC and fibroblast numbers and immunostaining intensities of TGF-ß, FGF-ß, and PDGF.