Oznur Kal

Effect of fingolimod (FTY720) on choroidal thickness in patients with multiple sclerosis

OBJECTIVE Using spectral domain optical coherence tomography (SD-OCT), to compare the choroidal thickness in a healthy population (group 1), with newly diagnosed multiple sclerosis (MS) patients (group 2), with MS patients who underwent β-interferon monotherapy (group 3) and MS patients who underwent fingolimod therapy for 1 year (group 4) METHODS: Twenty-five control subjects (25 eyes), 24 newly diagnosed (24 eyes) MS patients, 22 MS patients who underwent fingolimod monotherapy for 1 year (22 eyes), and 24 MS patients who underwent β-interferon monotherapy for 1 year (24 eyes) were included in this study. The control group consisted of age- and gender-matched healthy individuals. The choroidal thickness measurements were performed using a high-speed and high-resolution SD-OCT device. The choroidal thickness measurements were compared using a One Way Anova and Post-Hoc Tukey test. RESULTS Ninety-five eyes of 95 participants were included in this study. The mean age of the control group was 27.83±4.60, and it was 26.83±6.79, 27.87±6. 46 and 27.58±6.65 in the newly diagnosed MS group, fingolimod group and β-interferon group, respectively. In fingolimod group N-1000, N-1500 and T-1500 was significantly lower than control group. (p=0.026, p=0.06 p=0.13) CONCLUSION: Choroidal thickness values at N-1000, N-1500 and T-1500 levels in fingolimod group were found lower than in control but higher than in newly diagnosed MS group. This result can be explained with the therapeutic effect of the fingolimod on MS.

The protective effect of prophylactic ozone administration against retinal ischemia-reperfusion injury.

Abstract Introduction: Retinal ischemia-reperfusion (IR) injury is associated with many ocular diseases. Retinal IR injury leads to the death of retinal ganglion cells (RGCs), loss of retinal function and ultimately vision loss. The aim of this study was to show the protective effects of prophylactic ozone administration against retinal IR injury. Materials and methods: A sham group (S) (n = 7) was administered physiological saline (PS) intraperitoneally (i.p.) for 7 d. An ischemia reperfusion (IR) group (n = 7) was subjected to retinal ischemia followed by reperfusion for 2 h. An ozone group (O) (n = 7) was administered 1 mg/kg of ozone i.p. for 7 d. In the ozone + IR (O + IR) group (n = 7), 1 mg/kg of ozone was administered i.p. for 7 d before the IR procedure and at 8 d, the IR injury was created (as in IR group). The rats were anesthetized after second hour of reperfusion and their intracardiac blood was drawn completely and they were sacrificed. Blood samples were sent to a laboratory for analysis of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), total oxidant score (TOS) and total antioxidant capacity (TAC). The degree of retinal injury was evaluated according to changes in retinal cells and necrotic and apoptotic cells using the TUNEL method. Data were evaluated statistically with the Kruskal-Wallis test. Results: The number of RGCs and the inner retinal thickness were significantly decreased after ischemia, and treatment with ozone significantly inhibited retinal ischemic injury. In the IR group, the degree of retinal injury was found to be the highest. In the O + IR group, retinal injury was found to be decreased in comparison to the IR group. In the ozone group without retinal IR injury, the retinal injury score was the lowest. The differences in the antioxidant parameters SOD, GSH-Px and TAC were increased in the ozone group and the lowest in the IR group. The oxidant parameters MDA and TOS were found to be the highest in the IR group and decreased in the ozone group. Discussion: IR injury is also positively correlated with the degree of early apoptosis. This study demonstrated that ozone can attenuate subsequent ischemic damage in the rat retina through triggering the increase of the antioxidant capacity.

Evaluation of Dry Eye Using Anterior Segment Optical Coherence Tomography in Patients With End-Stage Renal Disease Undergoing Hemodialysis: Dry Eye Disease in Hemodialysis Patients

The aim of the present study was to evaluate dry eye parameters with conventional tests and tear meniscus with Anterior Segment Optical Coherence Tomography (AS‐OCT) in patients with end‐stage renal disease (ESRD). Thirty‐eight ESRD patients undergoing hemodialysis, and 40 healthy individuals were enrolled. An ocular surface disease index questionnaire (OSDI) was administered. Before conventional dry eye tests, tear meniscus were evaluated using AS‐OCT. After a complete ocular examination, Schirmer and break‐up time (BUT) tests were performed and probable corneal staining was investigated. Schirmer test and BUT values were significantly lower in ESRD patients (P < 0.05). OSDI scores and corneal staining scores were significantly higher in ESRD patients (P < 0.05). Tear meniscus height, tear meniscus depth, and tear meniscus area, which were obtained by AS‐OCT were significantly lower in patients with ESRD (P < 0.05). Tear meniscus evaluation using AS‐OCT is an effective and non‐invasive method to assess tear meniscus in patients with ESRD. Patients with ESRD undergoing hemodialysis should obtain regular ophthalmic examination, especially for dry eye.

Postconditioning Ozone Alleviates Ischemia-Reperfusion Injury and Enhances Flap Endurance in Rats

Abstract Introduction: Muscle-flap transferring is a routine approach utilized in reconstructive operations; however, flap morbidity is often a source of post-operative difficulty. Ischemia-Reperfusion Injury (IRI) is an important contributor to the viability of flaps after transferring. The goal of this research was for assess the probable useful impacts of ozone on flap survival in a rat muscle-flap design. Materials and Methods: We examined the effects of postconditioning ozone administration on viability of pedicled composite flaps. Twenty-eight Wistar rats were randomized into four groups: sham-operated (S), ischemia-reperfusion (IR), sham-operated + ozone (O), IR + ozone (IR + O), respectively. The animals were sacrificed on the eighth day. In a general histological evaluation, flap tissues were examined with a light microscope, and apoptotic cells were counted. The Apoptotic Index (AI) was then calculated. Flap-tissue samples were sent for analyses of malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and protein carbonyl (PCO), and blood samples were sent for analyses of Total Oxidant Score (TOS), and Total Antioxidant Capacity (TAC). Data were evaluated statistically using the Kruskal–Wallis test. Results: The histomorphometric score was remarkably greater in O (p = .002). The AI was greater in IR (p = .002). The antioxidant parameters values as regards SOD, GSH-Px, CAT, and TAC were found to be greater in O (p < .005). The oxidant parameters values as regards MDA, PCO, TOS were found to be greater in IR (p < .005). Discussion: The current research indicates that ozone application can attenuate the muscle-flap injury brought about by IR through triggering the increase of the antioxidant capacity.

Evaluation of retrobulbar blood flow and choroidal thickness in patients with rheumatoid arthritis

PurposeTo evaluate whether retrobulbar blood flow and choroidal thickness (CT) are affected in patients with rheumatoid arthritis (RA), and the relationship between these values.MethodsWe evaluated 40 eyes of 20 RA patients and 40 eyes of 20 healthy controls. The enhanced depth imaging optical coherence tomography, color Doppler imaging, was held. Statistical analysis was performed.ResultsPeak systolic velocity (PSV) of ophthalmic (OA) and central retinal artery (CRA) were significantly higher in RA. No significant difference was observed when end-diastolic velocity (EDV) of OA and CRA was compared between the groups. The resistivity index (RI) of OA and CRA was higher in RA. Perifoveal/subfoveal CT was lower in RA. Negative correlation was detected between the RI of OA and the perifoveal CT, and a positive correlation was detected between RI of CRA and CT.ConclusionsOcular hemodynamics is effected by RA and can exaggerate ocular complications of various vascular diseases such as diabetes mellitus, hypertension, retinal vascular occlusions.

Evaluation of the Ocular Blood Flow and Choroidal Thickness in Patients with Chronic Renal Failure

Received: 07.09.2017 Accepted: 20.11.2017 1Department of Radiology, Baskent University, Konya, Turkey 2Department of Internal Medicine, Baskent University, Konya, Turkey 3Department of Ophthalmology, Baskent University, Konya, Turkey Yazışma adresi: Enes Duman, Department of Radiology, Baskent University, Saray Cad. Hocacihan Mah. 42080 Selçuklu Konya Turkey e-mail: drenesduman@hotmail.com GİRİŞ

Evaluation of choroidal and retinal thickness measurements in adult hemodialysis patients using spectral-domain optical coherence tomography

PURPOSE To assess the effect of hemodialysis on retinal and choroidal thicknesses using spectral-domain optical coherence tomography (SD-OCT). METHODS In this prospective interventional study, 25 hemodialysis patients (17 male, 8 female) were enrolled. All participants underwent high-speed, high-resolution SD-OCT (λ=840 mm; 26.000 A-scans/s; 5 µm resolution) before and after hemodialysis. Choroidal thickness was measured perpendicularly from the outer edge of the retinal pigment epithelium to the choroid-sclera boundary at the fovea and at five additional points: 500 µm and 1000 µm nasal to the fovea and 500 µm, 1000 µm, and 1500 µm temporal to the fovea. Two masked physicians performed the measurements. Choroidal and retinal thicknesses before and after hemodialysis were compared. RESULTS The median choroidal thicknesses before and after hemodialysis were 182 µm (range, 103-374 µm) and 161 µm (range, 90-353 µm), respectively (P<0.001). The median retinal thicknesses were 246 µm (range, 179-296 µm) before and 248 µm (range, 141-299 µm) after hemodialysis (P>0.05). Systolic arterial pressure, diastolic arterial pressure, mean arterial pressure, heart rate, and ocular perfusion pressure significantly decreased after hemodialysis (P<0.001). Intraocular pressure did not vary significantly (P=0.540). CONCLUSION Hemodialysis seems to cause a significant decrease in choroidal thickness, whereas it has no effect on retinal thickness. This significant decrease in choroidal thickness might be due to the extensive fluid absorption in hemodialysis, which could result in decreased ocular blood flow.