Fatih C. Gundogan

Choroidal thickness in systemic arterial hypertension

Purpose To assess choroidal thickness changes in young adults with systemic arterial hypertension. Methods This prospective study comprised 80 hypertensive patients and 80 healthy control subjects. Choroidal thickness was measured with spectral-domain optical coherence tomography (SD-OCT) (RS-3000, Nidek). Choroidal thickness was obtained at the subfovea, 500 µm, 1000 µm, and 1500 µm nasal to the fovea (N500, N1000, N1500) and 500 µm, 1000 µm, and 1500 µm temporal to the fovea (T500, T1000, T1500). Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were measured with a mercury sphygmomanometer. Only the right eye values were used for statistical comparisons between the groups. Results Mean age was 23.8 ± 2.8 years in hypertensive subjects and 23.5 ± 2.1 years in the control group (p = 0.945). All choroidal thickness measurements (mean choroidal thickness, subfoveal choroidal thickness, all nasal and all temporal choroidal thicknesses) were significantly lower in hypertensive subjects (p<0.001 for subfoveal, N500, T500, T1000, T1500; p = 0.001 for N1000; and p = 0.012 for N1500). The correlations between choroidal thickness measurements and blood pressure (SBP, DBP, MAP) were insignificant (p>0.05 for all correlations). Choroidal thickness measurements were also insignificantly correlated with disease duration (p>0.05 for all correlations). Conclusions The results of this study demonstrated that choroidal thickness decreases in patients with systemic arterial hypertension. This may be caused by arteriolar sclerosis and vascular contraction caused by high intravascular pressure in the choroid.

Acute effects of cigarette smoking on multifocal electroretinogram.

Background:  Cigarette smoking was shown to have stimulant effects on pattern visual‐evoked potentials. The aim of this study was to investigate the acute effects of cigarette smoking on multifocal electroretinogram (mfERG).

Choroidal Thickness Changes in the Acute Attack Period in Patients with Familial Mediterranean Fever.

Purpose: The aim of this study was to evaluate choroidal thickness changes during acute attacks of familial Mediterranean fever (FMF). Methods: Fifty patients with FMF and 50 healthy controls were included. Choroidal thickness of each participant was measured at the foveola and horizontal nasal and temporal quadrants at 500-µm intervals to 1,500 µm from the foveola using spectral-domain optical coherence tomography. White blood cell count, erythrocyte sedimentation rate (ESR) and serum levels of fibrinogen and C-reactive protein (CRP) were evaluated. The clinical findings (peritonitis, arthritis and pleuritis) were noted. Results: Choroidal thickness was significantly thicker at all measurement points in FMF patients compared to healthy controls during an acute attack (p < 0.05). There were positive correlations between the choroidal thickness and ESR, fibrinogen and, particularly, CRP levels. Clinical findings did not change the choroidal thickness significantly (p > 0.05). Conclusions: Increased choroidal thickness in the acute phase of FMF is possibly related to the inflammatory edematous changes in the choroid.

Early Neurodegeneration of the Inner Retinal Layers in Type 1 Diabetes Mellitus.

Purpose: This study explores retinal structural changes in type 1 diabetes without clinically diagnosed diabetic retinopathy (DR). Methods: Peripapillary retinal nerve fiber layer (RNFL) thickness, macular ganglion cell complex (GCC) thickness, and macular thickness (MT) were measured in 90 type 1 diabetic patients by using spectral domain optical coherence tomography. The values were compared with 100 sex- and age-matched healthy controls. The independent t test was used to assess differences in the mean age, mean diabetic and ocular parameters, and the thickness values between the diabetic and control groups. Multiple linear regression analysis was performed to investigate the correlation between the thickness values and diabetic and ocular parameters. Results: Whole-RNFL, the superior and inferior quadrants, and the superior half of the peripapillary RNFL thicknesses were significantly thinner in diabetic patients compared with controls (p < 0.05). GCC thicknesses in the average macular, outer temporal superior and outer temporal inferior sectors were significantly thinner in diabetic patients (p < 0.05). Central and average MTs were similar in both groups (p > 0.05). There were significant negative correlations of the duration of type 1 diabetes with the inner nasal MT, inner temporal superior GCC thickness, inner nasal inferior GCC thickness, and outer nasal superior GCC thickness (p < 0.05). Similarly, there were significant negative correlations of the level of HbA1c with the whole-RNFL thickness, superior-half-RNFL thickness, and superior-quadrant-RNFL thickness (p < 0.05). Conclusions: Type 1 diabetic patients without clinically diagnosed DR had neurodegeneration in the inner retinal layers compared with healthy controls.

Color vision versus pattern visual evoked potentials in the assessment of subclinical optic pathway involvement in multiple sclerosis.

Background: Optic pathway involvement in multiple sclerosis is frequently the initial sign in the disease process. In most clinical applications, pattern visual evoked potential (PVEP) is used in the assessment of optic pathway involvement. Objective: To question the value of PVEP against color vision assessment in the diagnosis of subclinical optic pathway involvement. Materials and Methods: This prospective, cross-sectional study included 20 multiple sclerosis patients without a history of optic neuritis, and 20 healthy control subjects. Farnsworth-Munsell (FM) 100-Hue testing and PVEPs to 60-min arc and 15-min arc checks by using Roland-Consult RetiScan® system were performed. P100 amplitude, P100 latency in PVEP and total error scores (TES) in FM 100-Hue test were assessed. Results: Expanded Disability Status Scale score and the time from diagnosis were 2.21 ± 2.53 (ranging from 0 to 7) and 4.1 ± 4.4 years. MS group showed significantly delayed P100 latency for both checks (P < 0.001). Similarly, MS patients had significantly increased total error scores (TES) in FM-100 Hue (P < 0.001). The correlations between TESs and PVEP amplitudes / latencies were insignificant for both checks (P > 0.05 for all). 14 MS patients (70%) had an increased TESs in FM-100 Hue, 11 (55%) MS patients had delayed P100 latency and 9 (45%) had reduced P100 amplitude. The areas under the ROC curves were 0.944 for FM-100 Hue test, 0.753 for P100 latency, and 0.173 for P100 amplitude. Conclusions: Color vision testing seems to be more sensitive than PVEP in detecting subclinical visual pathway involvement in MS.

Diabetic Macular Edema.

Diabetic macular edema (DME), one the most prevalent causes of visual loss in industrialized countries, may be diagnosed at any stage of diabetic retinopathy. The diagnosis, treatment, and follow up of DME have become straightforward with recent developments in fundus imaging, such as optical coherence tomography. Laser photocoagulation, intravitreal injections, and pars plana vitrectomy surgery are the current treatment modalities; however, the positive effects of currently available intravitreally injected agents are temporary. At this point, further treatment choices are needed for a permanent effect. Sources of data selection: The articles published between 1985-2015 years on major databases were searched and most appropriate 40 papers were used to write this review article.

A comparative study between intravitreal triamcinolone and bevacizumab for macular edema due to central retinal vein occlusion with poor vision

Aim: To compare the effect of intravitreal bevacizumab and triamcinolone in patients with macular edema after central retinal vein occlusion (CRVO), presenting with poor visual acuity. Materials and Methods: It was a retrospective, comparative case series of 38 consecutive eyes, with macular edema secondary to CRVO, with 20/200 or worse vision, which were treated primarily either with intravitreal bevacizumab (1.25 mg; 24 eyes) or intravitreal triamcinolone (4 mg; 14 eyes). During follow-up, 3.6 ± 0.8 re-injections of bevacizumab and 2.4 ± 0.5 re-injections of triamcinolone were administered (P = 0.080). The main outcome measures were the best-corrected visual acuity and the central macular thickness by optical coherence tomography during 12 months of follow-up. Results: At 12 months, visual acuity (logMAR) was changed from 1.03 ± 0.39 (baseline) to 0.92 ± 0.39 (P = 0.374) and the central macular thickness was reduced from a baseline of 713.6 ± 179.3 μm to 310.8 ± 205.2 μm (P = 0.000). Neither the bevacizumab nor triamcinolone groups varied significantly in visual acuity and central macular thickness at 1, 3, 6, and 12 months after treatment. Neovascular glaucoma developed in two of the 14 eyes (14%) in the triamcinolone group. Conclusion: In patients with CRVO and poor vision, intravitreal bevacizumab and intravitreal triamcinolone were associated with a reduction in macular edema; however, neither treatment achieved significant visual acuity improvement by the 12-month follow-up.Aim: To compare the effect of intravitreal bevacizumab and triamcinolone in patients with macular edema after central retinal vein occlusion (CRVO), presenting with poor visual acuity. Materials and Methods: It was a retrospective, comparative case series of 38 consecutive eyes, with macular edema secondary to CRVO, with 20/200 or worse vision, which were treated primarily either with intravitreal bevacizumab (1.25 mg; 24 eyes) or intravitreal triamcinolone (4 mg; 14 eyes). During follow-up, 3.6 ± 0.8 re-injections of bevacizumab and 2.4 ± 0.5 re-injections of triamcinolone were administered (P = 0.080). The main outcome measures were the best-corrected visual acuity and the central macular thickness by optical coherence tomography during 12 months of follow-up. Results: At 12 months, visual acuity (logMAR) was changed from 1.03 ± 0.39 (baseline) to 0.92 ± 0.39 (P = 0.374) and the central macular thickness was reduced from a baseline of 713.6 ± 179.3 µm to 310.8 ± 205.2 µm (P = 0.000). Neither the bevacizumab nor triamcinolone groups varied significantly in visual acuity and central macular thickness at 1, 3, 6, and 12 months after treatment. Neovascular glaucoma developed in two of the 14 eyes (14%) in the triamcinolone group. Conclusion: In patients with CRVO and poor vision, intravitreal bevacizumab and intravitreal triamcinolone were associated with a reduction in macular edema; however, neither treatment achieved significant visual acuity improvement by the 12-month follow-up.

Is multifocal ERG a reliable index of macular function after triamcinolone acetonide injection in diffuse diabetic macular edema

Purpose To investigate the changes and the reliability of multifocal electroretinogram (mfERG) after intravitreal triamcinolone acetonide (IVTA) injection in diffuse diabetic macular edema (DDME). Methods Twenty-four eyes with DDME were treated with an intravitreal injection of 4 mg of triamcinolone acetonide. Visual acuity (VA), central macular thickness (CMT), mfERG, and intraocular pressures (IOP) were evaluated in the preinjection period and the 15th day, third month, and sixth month after IVTA injection. Results Age and gender of the patients were not significantly correlated to logMAR VA (p=0.888 for age, p=0.192 for gender), CMT (p=0.282 for age, p=0.625 for gender), or P1/N1 amplitudes/implicit times in mfERG at baseline (p>0.05 for age and gender). The correlation between logMAR VA and CMT at baseline also was not significant (r=0.069, p=0.750). The VA increased significantly at the 15th day (p<0.001). The VA increase persisted until the third month and decreased to preinjection values at the sixth month (p=0.324). CMT decrease was significant at the 15th day (p=0.012) but insignificant at the third and sixth months (p=1.000 for both). Correlations between logMAR VA change/CMT change at the 15th day were not significant (r=–0.043, p=0.843). Moreover, the correlation of CMT change with P1/N1 amplitude/implicit time changes was not significant (p>0.05 for all). Conclusions The positive effect of IVTA injection in DDME is reversible until the sixth month. Monitoring of the improvement in visual function by mfERG is violated possibly by irreversible macular dysfunction due to long duration of macular edema and primary neurophysiologic effects of diabetes on the retina.

The acute effect of cigarette smoking on pattern visual evoked potentials

Reports of tobacco-induced electrocortical activation and decrements in ocular blood flow in the acute faze indicated that this effect is mediated via nicotin’s action or neuronal systems. In this study, pattern visual evoked potentials were investigated in a group of male smokers (22 right eyes of 22 subjects) in separate real smoking and sham smoking sessions. On each session, pattern visual evoked potentials were recorded before smoking, immediately after smoking, and five minutes after smoking. Latency and amplitude values for P100 peaks were assessed and analyzed in each smoking condition for both real smoking and sham smoking sessions. Real smoking significantly decreased P100 latency values (p value related to difference between pre-smoking and immediately after smoking conditions is 0.009) and increased P100 amplitude values (p value related to difference between pre-smoking and fifth minute after smoking is 0.039). Statistically no significant difference was observed in sham smoking sessions. Our results are consistent with smoking-induced stimulant effects on pattern visual evoked potentials.

Stereoacuity testing discloses abnormalities in multiple sclerosis without optic neuritis.

Background: We aimed to determine the value of stereoacuity testing in detecting subclinical disease activity in patients with multiple sclerosis (MS) without a history or clinical evidence of optic neuritis. Methods: We enrolled 23 patients with MS and 23 age-matched and sex-matched healthy control subjects with Snellen acuities of 20/20 in both eyes. We recorded monocular pattern visual evoked potentials (PVEPs) to 60-minute and 15-minute check sizes and tested stereoacuity by the Randot stereoacuity (RSA) test. Results: The MS group showed delayed PVEP latencies to 60-minute and 15-minute patterns (P < 0.001 and 0.002). Stereoacuity by the RSA test was significantly worse in patients with MS than in control subjects (P < 0.001). In the MS group, the PVEP P100 latency and the RSA values showed significant positive correlations. There was no significant correlation between the time from MS diagnosis and the RSA and PVEP values. Conclusions: Based on this study, patients with MS without optic neuritis have considerable abnormalities in stereopsis. RSA testing may be a useful marker of subclinical disease activity in this condition.