Retinal Toxicity Assessment Following Vitreoretinal Surgery: A Comparison of Silicone Oil and Perfluoropropane Tamponade Using Diopsys® NOVA™.

PURPOSE: This study aimed to assess and compare the retinal toxicity associated with silicone oil (SO) and perfluoropropane (C3F8) tamponade following vitreoretinal surgery for fresh rhegmatogenous retinal detachment (RRD), utilizing the office-based Diopsys® NOVA™ system for evaluation. METHODS: Patients who underwent vitreoretinal surgery for fresh RRD and had SO (group 1) or C3F8 (group 2) tamponade were included in a prospective analysis. Flicker full field electroretinography (ffERG) and pattern electroretinography (PERG) tests were performed at 6 months postoperatively. RESULTS: Postoperative best corrected visual acuity (logMAR) was significantly different in group 1 and group 2 patients, 0.48 ± 0.3 and 0.30 ± 0.2, respectively. No significant disparities were found in demographic variables. Flicker ffERG and PERG recordings revealed notable alterations in retinal function parameters in the group 1 compared to the group 2. CONCLUSION: Our findings suggest a correlation between SO tamponade and retinal dysfunction, evidenced by office-based ERG measurements. The Diopsys® NOVA™ protocol offers clinical ease in assessing retinal function. Further controlled studies are essential to validate these findings and guide clinical practice effectively.

Perifoveal retinal thickness changes after intravitreal aflibercept injection for choroidal neovascularization in age-related macular degeneration.

OBJECTIVE: There has been some concern that anti-vascular growth factor treatment accelerates the development of macular atrophy in eyes with neovascular age-related macular degeneration. During the treatment with aflibercept, the thickness of choroid may decrease. This may lead to photoreceptor death. The rod cells are more susceptible to atrophic changes than cones during the disease. We aimed to find any thickness changes in the perifoveal outer nuclear layer, where the highest density of rods is found, during the aflibercept intravitreal injection therapy. MATERIALS AND METHODS: Retrospectively, forty-two patients who were treated for age-related macular degeneration with choroidal neovascularization were included in the study. After the first three loading doses, intravitreal injections were repeated every two months. Outer nuclear layer thicknesses were measured 2000 µm away from the center of the fovea with OCT, at a total of 20 points, located at 180 and 90°. The mean of these measurements was obtained before the treatment and 1 year after the therapy. Results were compared by using the Wilcoxon Rank Test. RESULTS: The mean visual acuity was 1,11±0,287 logMAR at the beginning and increased to 0,53±0,32 LogMAR after. Perifoveal thickness was significantly reduced when compared with the thickness before the treatment (p = 0.039, p < 0.05). This result was also significantly lower than the control group thicknesses (p = 0.035, p < 0.05). CONCLUSION: Anti-VEGFs can cause loss of phagocytic functions of RPE. The mechanism of the observed thinning of the ONL may be described as follows: VEGF emitted by the RPE normally helps to maintain the choriocapillaris. Thus, injecting an anti-VEGF intravitreally causes RPE atrophy, which leads to a decrease in the choroidal vascular index. This in turn causes first the rods, and later the cones, that are part of the outer nuclear layer, to start to die and disappear, hence the thinning of this layer. As aflibercept consists of parts of the extracellular domain of both the VEGFR1 and VEGFR2 receptors, that are held together by a human IgG1 backbone, this makes the binding of aflibercept to VEGF-A and VEGF-B stronger as compared to the binding of the previously used ranibizumab or bevacizumab (by nearly a factor 100 in the case of the most abundant isoform VEGF-A 165). Besides, aflibercept also binds very well to placental growth factor (PIGF), which is also associated with several ocular diseases.

MRI Results of Patients with Acute Isolyted Cranial Nerve Palsies.

AIM: To investigate the magnetic resonance imaging (MRI) results of patients complaining from diplopia with ocular nerve palsy. MATERIAL AND METHODS: A routine ophthalmic examination was performed, a neurological consultation was requested, and cranial MRI was performed for all patients. The image results were sorted into four groups: ischemic lesions, demyelinating disease lesions, tumors, and no lesions. White matter gliosis and cerebral infarcts were included in the ischemic lesion group. The medical histories of the patients were acquired from medical records. The chi-squared test was used to analyze the relationship between age and cranial MRI images and to analyze the relationship between the image and paresis type. The statistical significance threshold was set at p < 0.05, unless otherwise stated. RESULTS: Ischemic MRI images were the most common image type seen in our study. Third nerve paresis was significantly correlated with ischemic cerebral lesions observed by MRI (p=0.009). Furthermore, lesions were significantly correlated with patients aged above 50 years (p=0.004). There were no significant correlations between fourth or sixth nerve paresis and cranial ischemic images (p=0.680 and p=0.678, respectively). There were two instances of cerebral artery aneurysm, three instances of cerebral infarct, and one instance of intracranial mass, all in patients aged over 50 years. CONCLUSION: Although our patients had minimal or nonexistent neurological symptoms, some had serious cranial pathologies. These pathologies were commonly seen in patients aged over 50 years. We recommend performing MRI on all patients with binocular diplopia.

Investigating Estrogen and Progesterone Receptors in the Lacrimal Sacs of Individuals With and Without Chronic Dacryocystitis.

OBJECTIVES: Chronic dacryocystitis is usually seen in middle-aged or older women, suggesting that decreased estrogen and progesterone serum levels may be a causative factor in the disease pathology. However, the occurrence of the disease in premenopausal females and males suggests that there may be more to the explanation than the level of female sex hormones. The purpose of the present study was to investigate estrogen and progesterone receptor positivity in the lacrimal sacs of individuals with and without chronic dacryocystitis. METHODS: The study group included 50 female and 20 male patients diagnosed with chronic dacryocystitis. Lacrimal sac samples were taken during a dacryocystorhinostomy. The control group comprised 29 cadavers with no evidence of lacrimal system pathology in the health records. The samples were obtained transconjunctivally. Lacrimal sac samples from both groups were stained with the estrogen and progesterone receptor protein antigen. Fisher's exact test and a chi-square test were used to compare the receptor positivity results of premenopausal and postmenopausal women, and samples of those with dacryocystitis and cadaver sacs without the disease. RESULTS: In the control group, estrogen receptor positivity was observed in the samples of 2 premenopausal females. In the study group, estrogen receptor positivity was seen in 4 premenopausal females. There was no significant difference in estrogen receptor positivity between the premenopausal and postmenopausal female groups (p=0.41). A similar result was not established between the premenopausal and postmenopausal females in case group (p=0.056). No comparison was made of the progesterone receptor because only 1 example of progesterone receptor positivity was found in a premenopausal female in the dacryocystitis group. CONCLUSION: Estrogen receptor positivity did not seem to be a factor in chronic dacryocystitis physiopathology.

Predicting the refractive outcome and accuracy of IOL power calculation after phacoemulsification using the SRK/T formula with ultrasound biometry in medium axial lengths.

PURPOSE: To evaluate the accuracy of the SRK/T formula using ultrasound (US) biometry in predicting a target postoperative refraction of ±1.00D in eyes with medium axial length (AL) that underwent phacoemulsification. METHODS: The present study was a retrospective analysis, which included 538 eyes with an AL from 22.0 to 24.60 mm that underwent phacoemulsification and foldable intraocular lens (IOL) implantation (six different IOLs) in the bag. Preoperative AL was measured by US biometry and IOL power (IOLp) was calculated with the SRK/T formula. Patients had a complete ophthalmic examination, preoperatively and 1, 7, and 30 days after surgery. The achieved spherical equivalent (SE) and the prediction error (PE) were calculated. The prediction error was defined as the difference between attempted predicted target refraction and the achieved postoperative SE refraction. Statistical analysis was performed with SPSS V21. RESULTS: The mean age of the patients was 66.96±9.67 years, the mean AL was 23.29±0.62 mm, the mean K1 was 43.62±1.49D, the mean K2 was 43.69±1.53D, the mean IOL power was 21.066±1.464D, the mean attempted (predicted) SE was -0.178±0.266D, and the mean achieved SE was -0.252±0.562D. The mean PE (difference between predicted and achieved SE) showed a relatively hyperopic shift (mean ± standard deviation: 0.074±0.542D, ranging from -1.855 to 2.170D, P=0.001). A total of 93.87% of eyes were within ±1.00D of the PE and 92.75% of eyes within ±1.00D of achieved postoperative refraction. A total of 39 eyes (7.25%) had a refractive surprise. A total of 32 of 39 eyes were more myopic than -1.00D and 7 of them were more hypermetropic than +1.00D. There was no correlation between the mean PE and IOL type, AL, K1, K2, and IOLp. There were a positive statistically significant correlation between PE and age (r=0.095; P=0.028) and a negative statistically significant correlation between achieved SE and AL (Spearman's r=-0.125; P=0.04), and age (r=-0.141; P=0.01). CONCLUSION: The IOLp calculation using the SRK/T formula with US biometry may demonstrate very good postoperative refractive outcomes in medium eyes with a few refractive surprises.

Evaluation of bacterial contamination rate of the anterior chamber during phacoemulsification surgery using an automated microbial detection system.

AIM: To assess the incidence of anterior chamber bacterial contamination during phacoemulsification surgery using an automated microbial detection system (BacT/Alert). METHODS: Sixty-nine eyes of 60 patients who had uneventful phacoemulsification surgery, enrolled in this prospective study. No prophylactic topical or systemic antibiotics were used before surgery. After antisepsis with povidone-iodine, two intraoperative anterior chamber aqueous samples were obtained, the first whilst entering anterior chamber, and the second at the end of surgery. BacT/Alert culture system was used to detect bacterial contamination in the aqueous samples. RESULTS: Neither aqueous samples obtained at the beginning nor conclusion of the surgery was positive for microorganisms on BacT/Alert culture system. The rate of bacterial contamination during surgery was 0%. None of the eyes developed acute-onset endophthalmitis after surgery. CONCLUSION: In this study, no bacterial contamination of anterior chamber was observed during cataract surgery. This result shows that meticulous surgical preparation and technique can prevent anterior chamber contamination during phacoemulsification cataract surgery.