Evaluation of the effect of fasting on intraocular pressure, anterior segment parameters and density of crystalline lens and cornea.

PURPOSE: To evaluate the effect of fasting on anterior chamber depth, anterior chamber volume and corneal and lens density by Scheimpflug technology and to measure intraocular pressure changes. METHODS: Totals of 50 healthy fasting individuals in Ramadan (study group) and 50 healthy non-fasting subjects (control group) were included. Central corneal thickness (CCT), anterior chamber depth (ACD), anterior chamber volume (ACV), corneal density (CD) and lens density (LD) were evaluated with Scheimpflug technology. Intraocular pressure (IOP) was measured with applanation tonometry. Both eyes of each participant were examined and also compared. RESULTS: Comparison of groups: There was a statistically significant difference between CD, ACD, ACV and IOP (respectively, right/left eye: fasting: CD: 12.81 ± 0.76/12.73 ± 0.73; ACD: 2.92 ± 0.37 mm/2.93 ± 0.37 mm; ACV: 168.3 ± 41.82 mm3/183.34 ± 32.46 mm3; IOP: 13.80 ± 1.22 mmHg/14.88 ± 2.73 mmHg; non-fasting: CD: 13.28 ± 1.01/13.17 ± 0.77; ACD: 3.06 ± 0.31 mm/3.07 ± 0.31 mm; ACV: 167.46 ± 42.92 mm3/180.68 ± 31.45 mm3; IOP: 13.60 ± 1.65 mmHg/14.74 ± 2.93 mmHg) values on the right side (p < 0.01, p = 0.03, p = 0.04, p = 0.01, respectively). Although there was a statistically significant difference between the ACV, CD and IOP values on the left side (p < 0.01, p = 0.03, p = 0.01, respectively), no statistical significance was found for the ACV value on the left side (p = 0.08). CONCLUSION: The results demonstrated that, while fasting did not lead to any change in LD and CCT, it caused a small decrease in ACD and ACV, and a significant decrease in CD and IOP values. Scheimpflug technology seems to be a valuable tool for the evaluation of anterior segment changes in patients who are fasting.

Evaluation of the effect of smokeless tobacco (Maras powder) on choroidal and retinal blood flow: an optical coherence tomography angiography study.

ABSRTACT: PURPOSE: To investigate the acute and chronic effects of the use of smokeless tobacco (Maras powder) on macular and choroidal blood flow, via optical coherence tomography angiography (OCTA). METHODS: The study included 30 eyes of 30 patients using smokeless tobacco (ST) as the study group and 30 eyes of 30 healthy individuals as the control group. All subjects underwent a full ophthalmological examination, and baseline OCTA measurements were taken. Flow area in superficial capillary plexus (SCP), in deep capillary plexus (DCP), in choriocapillaris (mm2) and mean vascular density (VD) and foveal avascular zone in SCP and in DCP were assessed. Subfoveal choroidal thickness (SFCT) and central macular thickness were measured as well. RESULTS: The SFCT measurements were determined to be significantly low in the study group (p < 0.001). In the comparison of the study group measurements at 5 m, 30 m and 1 h after using ST compared to the baseline measurements, SCP and DCP flow area, VD, CC flow area and SFCT were determined to have significantly decreased, statistically (p < 0.001). CONCLUSION: OCTA could be important in showing that choroidal microvascular structures have been affected before occurence of the apparent clinical signs associated with acute and chronic ST use.

Quantitative analysis of retinal microcirculation in optical coherence tomography angiography in cases with Behçet's disease without ocular involvement.

PURPOSE: To evaluate the retinal vascular plexus and choriocapillaris structures in patients with non-ocular Behçet's disease (BD) using optical coherence tomography angiography (OCTA). METHODS: The study included 42 eyes of non-ocular BD patients (study group) and 40 eyes of 20 healthy subjects (control group). Flow area (mm2), mean vascular density (VD) (%) and foveal avascular zone (FAZ) (mm2) were measured using OCTA (Optovue Inc., Fremont, CA, USA). Subfoveal choroidal thickness (CT) (µm) and central macular thickness (CMT) (µm) measurements were also performed. RESULTS: The mean superficial capillary plexus, deep capillary plexus and choriocapillaris flow area values were found to be significantly lower in the study group than in the control group (p < 0.001, p < 0.001, p = 0.008, respectively). In respect of mean VD, a statistically significant difference was determined between the study and control groups in both superficial and deep VD (p < 0.001). No statistically significant difference was found out between the groups in respect of superficial FAZ, deep FAZ and CMT (p = 0.165, p = 0.477, p = 0.457, respectively). The subfoveal CT was also measured to be significantly thicker in the study group than in the control group (p < 0.001). CONCLUSION: The results obtained with OCTA revealed that there could be both retinal and choroidal involvement in non-ocular BD patients before the emergence of evident clinical findings.

Ocular perfusion pressure and intraocular pressure in pregnant women with severe preeclampsia.

OBJECTIVES: The aim of this study was to investigate whether severe preeclampsia (SPE) affects intraocular pressure (IOP) and ocular perfusion pressure (OPP). MATERIAL AND METHODS: This prospective and comparative study included 64 pregnant females, allocated into 2 groups as Group 1 (31 pregnant women with SPE) and Group 2 (33 normotensive pregnant women). IOP, systolic and diastolic blood pressure, OPP of all the subjects were measured after 20 weeks of gestation and prior to labor and medical therapy. RESULTS: The mean IOP values in Group 1 were not significantly different from those of Group 2 (p = 0.528). The mean OPP values in Group 1 were significantly higher than those of Group 2 (p < 0.001). There was no significant correlation between IOP and OPP levels. No significant differences were determined between the groups in respect of age, gestational age body mass index (BMI) (p < 0.269, p < 0.219 and p < 0.556 respectively). The mean systolic and diastolic blood pressure values were statistically significantly higher in Group 1 than in Group 2 (p < 0.001 and p < 0.001). CONCLUSIONS: Although high IOP was expected in SPE patients, it was found to be constant. This could have been due to an increase in aqueous humor outflow because of changes occurring in angiogenic and anti-angiogenic factors in SPE.

Evaluation of retinal and choroidal vascular structures in obsessive-compulsive disorder.

PURPOSE: To evaluate the optical coherence tomography-angiography (OCT-A) findings and choroidal vascularity index (CVI) of patients followed with a diagnosis of obsessive-compulsive disorder (OCD) by comparing them with the healthy control group (HCG). METHODS: This prospective study included 33 patients diagnosed with OCD and 32 HCG patients who followed up for at least 3 months. OCT-A images were obtained to evaluate the microvascular circulation, and enhanced HD line images were obtained for the CVI calculation of all patients. RESULTS: Statistical analysis results revealed that the rates of superficial vascular density in the fovea region and deep vascular density in the parafovea region decreased in the OCD group compared to the HCG group (P = 0.003 and P = 0.010, respectively). Subfoveal choroidal thickness values of the OCD group were lower than those of the HCG group (P = 0.008). While total choroidal area and lumen area values were lower in the OCD group than in the HCG group (P < 0.001 and P < 0.001, respectively); CVI values were similar in both groups (P = 0.436). CONCLUSION: The use of the OCT-A device, which is a non-invasive method for detecting retinal and choroidal changes in OCD cases, may provide insight into the pathogenesis of the disease.

Co-assessment of OCT-A and choroidal vascularity index data in multiple sclerosis patients.

OBJECTIVE: To evaluate optical coherence tomography-angiography (OCT-A) findings and choroidal vascular index (CVI) in patients with multiple sclerosis (MS). METHODS: 113 patients, including multiple sclerosis patients with optic neuritis attack (MSON+) and no optic neuritis attack (MSON-) and healthy control group (HCG), participated in this cross-sectional study. OCT-A images of all patients were taken and CVI was calculated. RESULTS: Superior flow (SF), deep flow (DF), foveal, and parafoveal superior vascular density (sVD) were decreased in the MSON+ group compared to HCG (p < 0.05). Optic disk flow (ODF) and optic disk head density (ONHD) values decreased in the MS group (p < 0.05). CVI was decreased in the MSON+ group compared to HCG (p < 0.05). There is a correlation between CVI and foveal and parafoveal sVD. CONCLUSION: Non-invasive diagnostic tools such as OCT-A and CVI can be used for early diagnosis and follow-up of microvascular pathologies in inflammatory diseases such as MS.

Investigation of Retinal Vascular Parameters and Choroidal Vascular Index in Patients Developing Hyphema After Unilateral Blunt Trauma.

BACKGROUND: To evaluate retinal and choroidal vascular changes in cases with hyphema after blunt ocular trauma that did not cause globe rupture or any retinal pathology. METHODS: This cross-sectional study included 29 patients who developed hyphema after unilateral blunt ocular trauma (BOT). The other healthy eyes of the same patients were evaluated as the control group. Optical coherence tomography-angiography (OCT-A) was used for imaging. In addition, choroidal parameters were compared by calculating the choroidal vascular index (CVI) and using choroidal thickness measurements by two independent researchers. RESULTS: Superior and deep flow values were significantly decreased in the traumatic hyphema group compared to the control group (p<0.05). Parafoveal deep vascular density (parafoveal dVD) values were decreased in traumatized eyes compared to control eyes (p=0.000). Vascular density values were similar other than that. In addition, there was a significant decrease in optic disc blood flow (ODF) and optic nerve head density (ONHD) values compared to the control group (p<0.05). In addition, no significant difference was observed between the groups in terms of mean CVI values (p>0.05). CONCLUSION: Non-invasive diagnostic tools such as OCTA and EDI-OCT can be used to detect and monitor early changes in retinal and choroidal microvascular flow in cases of traumatic hyphema.

Investigation of changes in retinal vascular parameters and choroidal vascular index values during the early recovery period of COVID-19: The COVID-OCTA study.

BACKGROUND: COVID-19 effects microvasculature in many tissues. This study investigated whether the choroidal structure is also affected. METHODS: This cross-sectional study included 80 patients with COVID-19 and the same number of age- and gender-matched healthy individuals. All participants' right eye measurements were examined. Optical coherence tomography angiography (OCTA) was used for imaging. Otherwise, two independent researchers used the Choroidal vascular index (CVI) for choroidal parameters calculation. RESULTS: Superior and deep flow values were lower in the COVID-19 group than in the control group, and vascular density (VD) values were lower in all regions in this group. Except for the superior mean VD, there was no statistically significant difference (p = 0.003). However, the COVID-19 group had significantly lower subfoveal choroidal thickness (SFChT) measurements than the control group (p = 0.001). In addition, no significant difference was observed between the groups in evaluating mean CVI values (p>0.05). CONCLUSION: Noninvasive diagnostic tools such as OCTA and EDI-OCT can be used to monitor early changes in diseases affecting microvessels, such as from COVID-19.

Comparing the effects of serum GPER-1 and oxidant/antioxidant levels on retinopathy in patients with diabetes and healthy individuals: a pilot study.

PURPOSE: This study aimed to determine the effect of serum G receptor-mediated protein-1 levels on the development of retinopathy in patients with diabetes in comparison with healthy individuals. METHODS: The study enrolled patients with diabetic retinopathy (Group 1), patients without diabetic retinopathy (Group 2), and healthy individuals (Group 3). Levels of serum progesterone, serum G receptor-mediated protein-1, estradiol, oxidant/antioxidants, and thyroid-releasing hormones were analyzed and compared among the groups. Post-hoc analysis was performed to compare the subgroups in which significant differences were found. RESULTS: Groups 1, 2, and 3 each included 40 patients. A significant difference was found among all groups in terms of serum G receptor-mediated protein-1, oxidant/antioxidant, and estradiol levels (p<0.01), but no significant difference was found in terms of thyroid-releasing hormone or progesterone (p=0.496, p=0.220, respectively). In the post-hoc analysis of the groups with significant differences, another significant difference was found among all groups for serum G receptor-mediated protein-1 and oxidant/antioxidant levels (p<0.05). Serum G receptor-mediated protein-1 and oxidant levels were positively correlated, whereas serum G receptor-mediated protein-1 and antioxidant levels were negatively correlated (r=0.622/p<0.01, r=0.453/p<0.01, r=0.460/p<0.01, respectively). The multiple regression analysis showed that increased levels of serum G receptor-mediated protein-1 may help prevent diabetic retinopathy. CONCLUSIONS: Serum G receptor-mediated protein-1 levels, which were the highest in the diabetic retinopathy Group, increased as the oxidant/antioxidant balance changed in favor of oxidative stress. This appears to be a defense mechanism for preventing neuronal damage.

Evaluation of Macular Microcirculation in Healthy Children Using Optical Coherence Tomography Angiography.

OBJECTIVES: This study was designed to evaluate macular perfusion in a healthy pediatric population using optical coherence tomography angiography (OCTA). METHODS: Fifty-three eyes of 30 healthy children (20 boys and 10 girls) were included in this prospective, cross-sectional study. Age, gender, foveal thickness (FT), superficial foveal avascular zone area (FAZs), deep foveal avascular zone area (FAZd), superficial capillary plexus flow area (SCP), deep capillary plexus flow area (DCP), choriocapillaris flow area (CC), vascular density in the SCP (VDs), vascular density in the DCP (VDd), and subfoveal choroidal thickness (SFCT) were evaluated. RESULTS: The mean age was 12.0±4.0 years (range: 6-15 years). Gender did not have a statistically significant influence on the FAZs or FAZd. However, there was a positive correlation between the CC and age (r=0.31; p=0.025). The FAZs and FAZd were negatively correlated with the FT (p<0.001). The VDd was positively correlated with the FT (p=0.03) and was negatively correlated with the FAZd (p=0.019). CONCLUSION: The present study determined normative data of OCTA parameters in healthy children and provides useful insight into the relationship between age, macular microvascular networks, and the FAZ.

Antenatal and postpartum comparison of HD-OCT findings of macula, retinal nerve fiber layer, ganglion cell density between severe preeclampsia patients and healthy pregnant woman.

AIM: To investigate the effects of severe preeclampsia on the retinal nerve fiber layer (RNFL), macula thickness and ganglion cell density in pregnancy and postpartum, using High Definition Optical Coherence Tomography (HD-OCT). MATERIAL AND METHOD: The study group included 28 stable pregnant patients diagnosed with severe preeclampsia and the control group, 28 age and gestational week-matched healthy pregnant women. HD-OCT measurements were taken by the same researcher using a Cirrus HD-OCT device and were repeated at 8 weeks postpartum. RESULTS: The mean systolic pressure, diastolic pressure, and intraocular perfusion pressure (IPP) values measured in pregnacy were determined to be higher in the preeclampsia group than in the control group (158.4 ± 7.3 vs.113.6 ± 6.8, 97.0 ± 5.7vs.73.8 ± 5.9 and 68.1 ± 3.9 vs.48.8 ± 3.3 mm Hg, respectively) (p < 0.05 for all). The mean RNFL, macula thickness, ganglion cell analysis, and intraocular pressure (IOP) values during pregnancy were determined to be similar in both groups (p > 0.05 for all). No significant difference was determined postpartum between the groups in respect of mean systolic pressure, diastolic pressure, RNFL, macula thickness, ganglion cell analysis, and IOP values (114.3 ± 5.0 vs 114.6 ± 5.9 mm Hg, 74.6 ± 5.1 vs.74.5 ± 5.5 mm Hg, 96.0 ± 7.3 vs. 95.9 ± 6.7 µm, 228.2 ± 18.9 vs.234.5 ± 15.4 µm, 81.8 ± 8.0 vs. 84.2 ± 4.6 µm, 14.1 ± 2.4 vs.13.8 ± 2, respectively) (p < 0.05 for all). Mean IPP during pregnancy was higher than the mean postpartum IPP in the severe pre-eclampsia group (68.1 ± 3.9 vs 49.1 ± 3.1 mm Hg) (p < 0.001). CONCLUSION: This is the first study to have evaluated ganglion cell density of the retina, macula thickness, and RNFL using HD-OCT in severe pre-eclampsia cases, both during pregnancy and postpartum.

Quantitative assessment of the effect of fasting on macular microcirculation: an optical coherence tomography angiography study.

AIM: To analyse the effect of fasting on the retinal vascular plexus and choriocapillaris structures in healthy subjects via Optical Coherence Tomography Angiography (OCTA). METHODS: In this prospective study, OCTA scans of 98 eyes in 49 healthy subjects were compared in fasting and non-fasting period. All cases had a full ophthalmological examination, with OCTA parameters measured, including superficial flow area (SCP) (mm2), deep flow area (DCP) (mm2), choriocapillaris flow area (CC) (mm2), superficial and deep vascular density (SVD and DVD, respectively) (%), superficial foveal avascular zone area (FAZs) (mm2), deep foveal avascular zone area (FAZd) (mm2), subfoveal choroidal thickness (SFCT) (µm) and central macular thickness (CMT) (µm). RESULTS: The mean SCP, DCP and CC flow area values were induced to be significantly lower in a fasting than a non-fasting period (p<0.001, p<0.001, p=0.049, respectively). The mean VD in a fasting period was statistically significantly lower than in a non-fasting period at the SCP level (p=0.009). No statistically significant difference was found between the two periods in respect to DVD, FAZd and CMT (p=0.068, p=0.653 and p=0.531, respectively); however, FAZs were significantly lower in a non-fasting than fasting period (p=0.038). The SFCT was determined to be statistically significant and thicker during a fasting period (p<0.001). CONCLUSION: The current study documented several physiological changes in a fasting period, such as changes in SCP, DCP, CC flow, SVD and DVD, via OCTA.

Posterior ocular blood flow in preeclamptic patients evaluated with optical coherence tomography angiography.

OBJECTIVE: The aim of the present study was to examine the effects of preeclampsia on posterior ocular blood flow through optic coherence tomography angiography (OCTA). STUDY DESIGN: The study included preeclamptic pregnant women (group PPW), healthy pregnant women (group HPW) and control non-pregnant women (group CNPW). The blood flow area of retina, optic nerve head and choriocapillaris were assessed through OCTA. RESULTS: Retinal superficial blood flow area (RSBFA) was similar in group PPW, HPW and CNPW (p = 0.101); likewise, there was not any difference in retinal superficial parafoveal vessel density (RSPFD) between the groups (p = 0.685). There was not any difference detected in retinal deep blood flow area (RDBFA) in group PPW, HPW and CNPW), likewise retinal deep parafoveal vessel density (RDPFD) was found similar between the groups (p = 0.184). The choriocapillaris blood flow area (CBFA) was different between the groups (p = 0.000) and less in the group PPW than in group HPW. The CBFA was 1.875 ±â€¯0.05 mm2 in group the PPW, 1.928 ±â€¯0.05 mm2 in the group HPW and 1.464 ±â€¯0.06 mm2 in the group CNPW. Similarly, the optic nerve head blood flow area was lower in the group PPW compared to the group HPW (1.567 ±â€¯0.38 mm2, 1.690 ±â€¯0.20 mm2 and 1.592 ±â€¯0.25 mm2 in the group PPW, group HPW and group CNPW respectively; p = 0.002). CONCLUSION: Posterior segment ocular blood flow may be diminished in preeclamptic women. OCTA may enable to monitor ocular blood flow dynamics and give important clues in the diagnosis of retinal vascular pathologies accompanied by systemic diseases.

Density of crystalline lens and cornea in different trimesters of pregnancy.

PURPOSE: To evaluate topographic measurements of the anterior segment and densitometric measurements of the cornea and lens by Pentacam HR in different trimesters of pregnancy. METHODS: This prospective study included 150 healthy pregnant women in their first, second, or third trimester (Groups 1, 2 and 3, respectively) and 54 non-pregnant healthy women (Group 0). Topographic measurements, including central corneal thickness (CCT), corneal volume (CV), anterior chamber depth (ACD), corneal densitometry (CD) and lens densitometry (LD), were done with the Pentacam HR (Oculus, Wetzlar, Germany). The measurement results of the healthy pregnant women and non-pregnant healthy women were compared. RESULTS: CD values were found in Group 1 to be 13.19, in Group 2 to be 13.16, in Group 3 to be 13.17 and in Group 0 to be 13.22 (p = 0.811). The mean Group 1, Group 2, Group 3 and Group 0 LD-horizontal was 5.40 ± 0.5, 5.47 ± 0.38, 5.53 ± 0.44, 5.36 ± 0.43, respectively. The mean Group 1, Group 2, Group 3 and Group 0 LD-vertical was 5.6 ± 0.43, 5.66 ± 0.32, 5.71 ± 0.40 and 5.5 ± 0.44, respectively. Area LD values were higher in the advanced trimester period, and the only statistically significant difference was between Group 3 and Group 0 (p = 0.025). The difference between three-dimensional (3D) and peak LD values was not statistically significant between the groups (p = 0.89 and p = 0.91, respectively). DISCUSSION: The Pentacam HR seems to be an important option for the evaluation of LD, CD and topographic measurements of the anterior segment in pregnancy. In the present study, CD and LD, including LD-horizontal, LD-vertical, peak and 3D values, were not significantly different between pregnant women and non-pregnant women.

Bilateral Papillophlebitis in a Patient with Mutation of Metilenetetrahydrofolate Reductase Enzyme.

Papillophlebitis is known as central retinal vein occlusion seen in young patients. It usually presents as unilateral optic disc edema with cotton wool spots and hemorrhage in the peripapillary region. As it may be due to many autoimmune and inflammatory causes, a thorough systemic evaluation of the patient is warranted. In this case report we describe a bilateral, simultaneous papillophlebitis case thought to be related to hyperhomocysteinemia secondary to C677T polymorphism of methylenetetrahyrofolate reductase enzyme.