To evaluate the changes in several ocular parameters, including choroidal thickness, during and after hemodialysis. Twenty-seven eyes of 27 patients with chronic renal failure undergoing hemodialysis were included. The patients underwent an ophthalmic examination, including intraocular pressure, central corneal thickness, iridocorneal angle, subfoveal choroidal thickness, and blood pressure, just before a hemodialysis session, during the second hour of the session, and half an hour after the end of the session. Body weight was measured before and after the session, and ultrafiltration volume was noted after the session. Central corneal thickness, intraocular pressure, and subfoveal choroidal thickness were measured by optical coherence tomography. In comparison with baseline levels, mean intraocular pressure and central corneal thickness increased significantly during the second hour of hemodialysis (p=0.001 and p=0.011, respectively) and showed no significant changes after hemodialysis (p=0.844 and p=0.246, respectively). Mean iridocorneal angle did not significantly change during the second hour of hemodialysis (p=0.101) and after hemodialysis (p=0.589). Mean subfoveal choroidal thickness was significantly lower during the second hour of hemodialysis (p<0.001) and after hemodialysis (p<0.001). Mean intraocular pressure and central corneal thickness increased and subfoveal choroidal thickness decreased during the second half of the hemodialysis session. During the second half of the session, intraocular pressure and central corneal thickness had a trend toward reduction, while subfoveal choroidal thickness had a relatively steady course. Because of possible fluctuations in the values, it would be reasonable to evaluate the changes not only from before to after hemodialysis but also during hemodialysis when analyzing the ocular effects of dialysis.
1 October 2019 in Turkish Journal of Ophthalmology
To evaluate the clinical results of combined pars plana vitrectomy (PPV) with Landers wide-field temporary keratoprosthesis and penetrating keratoplasty (PK). From January 2016, traumatic eyes with coexisting corneal and vitreoretinal diseases that underwent combined keratoprosthesis/PPV/PK surgery were retrospectively evaluated. Demographic characteristics, visual acuity (VA), intraocular pressure (IOP) and clinical findings of the cornea, lens, and retina were recorded during the follow-up. Cases with clear corneal graft, attached retina, normotonic IOP, and improved or stable VA were considered successful. Eight eyes were enrolled in the study. The mean follow-up time was 21.1±8.20 months. Surgery was performed a mean of 23 (10-40) days after trauma. Preoperative VA ranged from no light perception to counting fingers from 50 cm. Postoperatively, corneal graft was clear in 5 patients (62.5%) and retina was attached in 6 eyes (75%). Chronic hypotonia developed in 3 patients (37.5%). VA was unchanged in 3 patients and improved in 5 patients. A total of 5 cases (50%) were considered successful. Shorter interval between trauma and surgery was associated with higher likelihood of success (p=0.043). No significant difference was observed between the groups in terms of type or location of trauma (p=1; p=0.143). Although the functional results are not very satisfactory, the combined procedure provides a final opportunity for preserving remaining vision and anatomic reconstruction in eyes that will otherwise result in phthisis due to severe anterior and posterior segment pathologies.
18 November 2020 in International Journal of Ophthalmology
To compare changes in anterior segment topography and axial length (AL) evaluated with Pentacam and IOL Master after pars plana vitrectomy (PPV) performed with and without vitreous base shaving. This prospective study included patients who underwent PPV or phacoemulsification+PPV (Phaco+PPV) for various indications. Patients who underwent total posterior hyaloid detachment and excessive vitreous base shaving with scleral indentation were referred to as complete PPV (c-PPV). The patients whom posterior hyaloid was separated as far as the posterior arcades and vitreous base shaving with scleral depression was not performed were classified as the partial PPV (p-PPV) group. All patients underwent detailed ophthalmologic examinations preoperatively and 1wk, 1, and 3mo postoperatively. Changes in the anterior chamber depth (ACD), anterior chamber volume (ACV), iridocorneal angle (ICA), central corneal thickness (CCT), and keratometric measurements (K1 and K2) were evaluated with Pentacam HR. Changes in the AL measurements were analyzed with IOL Master. A significant increase in ACD was observed in c-PPV cases (P=0.02), but this increase was not significant in the p-PPV group (P=0.053). In contrast, ICA increased significantly in the c-PPV group (P=0.02) but decreased in the p-PPV group (P=0.09). BCVA was significantly improved in the c-PPV group from week 1 (P0.05 for all). Incomplete posterior hyaloid excision and not removing the vitreous base in PPV surgeries may create a more stable anterior chamber, thus preventing the downward movement of the lens-iris diaphragm, and may cause ciliary body retraction, thereby reducing ICA. Awareness of these effects can provide some amount of guidance to physicians in selecting the appropriate PPV procedure and preempting surgical complications.
20 October 2020 in European Journal of Ophthalmology
The structural and vascular changes in the retina and choroid in women in the third trimester of pregnancy were analyzed using optical coherence tomography angiography (OCTA). Forty women in the third trimester of uncomplicated pregnancy and 40 age-matched healthy women were included. Vascular density (VD) in the superficial and deep capillary plexuses (SCP/DCP), foveal density (FD), and foveal avascular zone (FAZ) area and perimetry measured with OCTA, as well as OCT measurements of central macular thickness (CMT) and choroidal thickness (CT) were compared between the groups. Correlations between structural OCT parameters and vascular OCTA metrics were analyzed. The mean gestational age was 34 (28–41) weeks. Mean age was comparable in the groups (p = 0.732). The pregnant women had significantly higher parafoveal DCP-VD (p = 0.015), FAZ area (p = 0.044), and FD (p = 0.002). Mean subfoveal CT was 21 µm higher in pregnant women but was not significant (p = 0.472). There was no difference in CMT (p = 0.448). FAZ metrics were positively correlated with CT in pregnants and with CMT in the control group (p < 0.05). Parafoveal VD was negatively correlated with CT in the control group (p < 0.05). After adjusting for CT and CMT, the significant difference in VD and FD persisted (p < 0.05), while the difference in FAZ area lost significance (p > 0.05). Considering the effects of the probable covariant factors CMT and CT, systemic changes in pregnant women in their third trimester may cause an increase in VD in the macula and parafoveal DCP.
23 November 2018 in Cutaneous and Ocular Toxicology
Objective: To compare the possible toxic effects of three light sources used in vitreoretinal endoillumination systems; halogen, xenon, and light-emitting diode (LED) on retinal pigment epithelium (RPE) cell cultures, after two different exposure times. Materials and Methods: ARPE-19 human RPE cell cultures were exposed to halogen, xenon and LED light sources at a distance of 1,5 cm for 30 and 60 minutes with equal lumen output levels. Cells in the control group were not exposed. RPE cell cultures were compared in terms of cell viability, DNA damage, apoptosis rate and IL-1ß, IL-6 and TNF- α levels. Results: The halogen light group showed significantly more DNA damage, higher TNF-α, IL-1β and IL-6 levels and lower viable cell count at 30 minutes compared to the control group. The rates of early and late apoptosis were also significantly higher at 60 minutes. There were no statistically significant differences in any of the parameters between the xenon and LED light sources and the control group at 30 or 60 minutes. Conclusion: New generation lights, xenon and LED, seem to be safe in terms of RPE cells. Halogen light may cause toxic effects on RPE cells when used for a long time with maximal power output.
10 August 2021 in European Journal of Ophthalmology
Purpose: This study aimed to compare type 1 choroidal neovascularization (CNV) characteristics in eyes with pachychoroid neovasculopathy (PNV) and neovascular age-related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA). Methods: Treatment naive 23 eyes of 23 patients with PNV and 24 eyes of 24 patients with nAMD were evaluated. The height of pigment epithelial detachment (PED) and the central macular thickness were determined. OCTA sensitivity, CNV area, morphological patterns, and retinal superficial capillary plexus vessel density (SCP-VD) values were compared. The frequency of quiescent CNV, subretinal hyperreflective exudation (SHE), subretinal/intraretinal fluid, serous PED, double-layer sign (DLS), and pachyvessels were noted. Results: CNV was detected on OCTA in 83.3% of nAMD eyes and 91.3% of PNV eyes ( p = 0.66). Indistinct pattern was more common (74% vs 50%) and the CNV area (mm2) was smaller in PNV (0.77 ± 0.54 vs 1.57 ± 1.43) but did not reach significant levels ( p = 0.27 and 0.33 respectively). SCP-VD was similar between the groups ( p = 0.38). Statistically significant differences were found between groups in age and subfoveal choroidal thickness ( p < 0.05). DLS and pachyvessels were found to be more frequently in PNV ( p < 0.05). However, both groups had similar rates of quiescent CNV, SHE, subretinal/intraretinal fluid, and serous PED ( p > 0.05). Conclusion: Morphological features, area, and activation findings of type 1 CNV may play a limited role in differentiating nAMD and PNV cases.