Depth Imaging Optical Coherence Tomography Research Articles

Evaluation of the Activity of Vogt–Koyanagi–Harada Disease; A Comparison of Indocyanine Green Angiography Scoring, Enhanced Depth Imaging Optical Coherence Tomography, and Choroidal Vascularity Index

Abstract Purpose: To investigate the correlation between choroidal biomarkers using enhanced depth imaging optical coherence tomography (EDI-OCT) and indocyanine green angiography (ICGA) scoring for monitoring the activity of Vogt–Koyanagi–Harada (VKH). Methods: Patients who were not in the acute phase of VKH were recruited. Simultaneous EDI-OCT and ICGA were captured in seven patients only at baseline, in six patients at the 3-month follow-up, and in two patients at both the 6- and 9-month follow-ups. Subfoveal choroidal thickness (SFCT), subfoveal choroidal area (SFCA), and choroidal vascular index (CVI) were measured on EDI-OCT using FIJI software and a denoising system. ICGA scoring was performed. Results: Fifteen subjects with the median of 4-month follow-up were recruited. Forty-eight pairs of EDI-OCT and ICGA were investigated. In univariate analysis, ICGA scores were positively associated with SFCT, and SFCA, but negatively with CVI. The strength of correlation between ICGA scores and SFCT was strong (correlation coefficient: 0.91). In multivariate analysis, only SFCT remained significant (B: 2.4, 95% confidence interval: 1.9–3.0; P < 0.001). Conclusions: SFCT can be an acceptable representative of the subclinical inflammatory activity of VKH. As an alternative to ICGA, SFCT functions better than SFCA and CVI.

Choroid and Retinal Effects of Epilepsy and Epilepsy Subgroups.

The objective were to evaluate structural alterations in the retina and choroid tissue of epilepsy patients and subtypes using enhanced depth imaging optic coherence tomography (EDI-OCT). 46 epilepsy patients and 50 sex- and age-matched control patients were analyzed in the study. Patients' epilepsy types were recorded. The central macular thickness (CMT), retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and choroidal thickness (CT) were investigated through the Spectralis-OCT device (SD-OCT). Image-J program was used to calculate the total choroidal area (TCA), the luminal area (LA), stromal area (SA), and the choroidal vascularity index (CVI). CMT, TCA, LA, and SA outcomes were substantially reduced in epilepsy patients than in healthy controls. There was no significant difference between CT, RNFL, GCL, CVI results. There were no statistically significant differences between patients with partial and generalized epilepsy (p>0.05 for each). According to the results of our study, epilepsy disease has effects on the posterior segment of the eye. To the best of our knowledge, our study is the first to evaluate CVI in patients with epilepsy and the epilepsy subgroups.

Uncommon case of basal linear deposits and its tomographic and indocyanine green angiography findings

Purpose: To report a rare and uncommon case of patient presenting drusen associated to basal linear deposit (BlinD) and macular vitelliform material (VM).Methods: Patient was assessed with multimodal imaging: fundus autofluorescence (FAF), indocyanine green angiography (ICGA) and enhanced depth imaging optical coherence tomography (EDI‐OCT). Electroretinogram (ERG) and visually evoked potentials (VEP) along with systemic evaluation were also performed.Results: A 52‐year‐old woman consulted for ophthalmological check‐up, without any complaint. Past history revealed breast cancer treated with chemotherapy and hormone therapy, currently in remission. Visual acuity was 10/10 in the right eye (RE) and 8/10 in the left eye (LE). Slit‐lamp anterior examination was unremarkable. Fundus examination revealed multiple interlaced round yellowish lesions mainly in the posterior pole associated to a pigmented macular lesion on the LE. FAF showed bilateral macular hypoautofluorescent lesions. ICGA highlighted bilateral scattered hypofluorescent spots (SHS) mainly noted in the late phase, distributed throughout the posterior pole, with partial confluence. EDI‐OCT featured the presence of drusenoid retinal pigment epithelium (RPE) elevation along with a thick and distinctive hyperreflective band between the RPE and Bruch's membrane (BM). Associated bilateral hyperreflective VM were also detected. ERG and VPE were unremarkable. Patient underwent systemic evaluation insuring absence of cancer recurrence, choroidal metastases, paraneoplastic syndrome or any systemic disease.Conclusions: BlinD is defined as a deposit located between the RPE and the BM. Recently, this entity has been correlated with SHS seen in late stages on ICGA and might be a precursor sign of age‐related macular degeneration. Associations between drusen and BlinD and between drusen and VM have been previously reported; however, the concomitance of these three features has, to our knowledge, never been reported.

The Influence of Seasonal Allergic Conjunctivitis and Its Treatment on Choroidal Vascular Index

Purpose: To evaluate the the effects of seasonal allergic counjunctivitis (AC) and its treatment upon choroidal structure such as choroidal thickness (ChT) and choroidal vascular index (CVI) through the use of topical antihistamine agents. Methods. The 60 eyes of 30 patients were included in the AC group. Another 30 patients were included in the control group. The choroid was imaged by using enhanced depth imaging optical coherence tomography (EDI-OCT) instrument without pupillary dilation. ChT was defined as the area between the outer hyperreflective border of the RPE and the sclerochoroidal border at the fovea, 750 µm temporal to the fovea and 750 µm nasal to the fovea. Image J was used to measure CVI. With the images obtained from EDI-OCT, the total choroidal area (TCA), luminal area (LA), stromal area (SA), and CVI were calculated using the binarization method. Results. The mean ChT value in the AC group was 358.5 ± 93.8 µm at baseline and 356.8 ± 86.6 µm following 1 month of treatment. Meanwhile, the mean ChT in the control group was 316.6 ± 60.7 µm. The mean CVI value was 66.65 ± 2.98 in the control group, 70.75 ± 3.26 in the AC group at baseline, and 69.50 ± 3.17 following 1 month of treatment. Statistically significant difference was tracked between control and AC group (p = 0.028) and control group and posttreatment values (p=0,031). There were no statistically significant difference between initial AC treatment values and posttreatment values for all of the measurements. Conclusion. ChT and CVI can increase in patients with AC due to inflammation and increased vascular permeability. Although symptoms and signs related to AC may disappear after the treatment, effects in the choroid do not immediately normalize.

Evaluation of choroidal thickness and retinal nerve fiber layer thickness in Chinese pregnant women and healthy non-pregnant women

PurposeTo evaluate choroidal thickness and retinal nerve fiber layer (RNFL) thickness in different trimesters using enhanced depth imaging optical coherence tomography (EDI-OCT). MethodsA prospective comparative study included 45 healthy pregnant women in the first trimester, 45 women in the second, 45 women in the third and 45 healthy non-pregnant women as the control group. Macular choroidal thickness was measured at three locations: The subfoveal, 1 ​mm temporal, and 1 ​mm nasal from the fovea with EDI-OCT. Peripapillary choroidal thickness (PPCT) and RNFL thickness parameters were automatically calculated by the Spectralis OCT. ResultsThe subfoveal, temporal and nasal macular choroidal thickness were all significantly thicker in the second trimester, compared with those parameters in the first, the third trimesters and the control group (all P ​< ​0.05). The PPCT was significantly increased in the second trimeter compared with the control group at global, temporal, temporal inferior, nasal and nasal inferior positions (all P ​< ​0.05). The RNFL thickness was also significantly increased in pregnant women at nasal superior and nasal inferior quadrants (all P ​< ​0.05). ConclusionsThe choroidal thickness in pregnant women was found to be thicker than the control group, regardless of macular or optic disc location. Findings of RNFL thickening might indicate subclinical involvement of the central nervous system.

Optic Disc Drusen Prevalence in Patients With Retinitis Pigmentosa: A Cross-Sectional Study.

Studies of patients with retinitis pigmentosa (RP) have reported an increased prevalence of optic disc drusen (ODD) compared with the ODD prevalence in the general population. The diagnostic gold standard method for identifying ODD is enhanced depth imaging optical coherence tomography (EDI-OCT), but this modality has not previously been used systematically for identifying ODD in patients with RP. This study aimed to estimate the prevalence of ODD in patients with RP using EDI-OCT. In this cross-sectional study, 40 patients with clinically diagnosed RP aged 18 years or older were included. All patients underwent an ophthalmic examination, including kinetic perimetry, EDI-OCT of the optic nerve head, and fundus photography. Genetic testing with a next-generation sequencing panel of retinal dystrophy genes was performed on the RP patients without a prior genetic diagnosis. Twelve patients (30.0%) had at least one ODD. Six patients had bilateral ODD. No significant differences between patients with and without ODD were found according to age, refraction, best-corrected visual acuity, Bruch membrane opening, or visual field. The genetic variation causing RP was found in 11 of 12 cases in the ODD group and in 17 of 28 cases in the group without ODD. We found the prevalence of ODD in patients with RP to be 30.0%. This is 15 times higher than in the general population and much higher than previously estimated in most studies, potentially indicating that the 2 conditions might be pathogenically related.

Choroidal Morphology and Systemic Circulation Changes During the Menstrual Cycle in Healthy Japanese Women.

Changes in systemic circulatory dynamics and choroidal thickness are poorly understood. This study aimed to investigate the time course of changes in choroidal morphology during normal menstrual cycles in healthy women using enhanced depth imaging optical coherence tomography (EDI-OCT). This prospective study included 15 left eyes of 15 healthy Japanese women (mean age, 20.2 ± 0.8 years) with a normal menstrual cycle. Using EDI-OCT, the subfoveal choroidal thickness (SCT) was manually measured during the late follicular and mid-luteal phases. Intraocular pressure (IOP), systolic, diastolic, and mean blood pressure (SBP, DBP, and MBP), and heart rate (HR) were also evaluated during these phases. SBP, DBP, and MBP were significantly elevated in the mid-luteal phase. The average SCT was significantly decreased in the mid-luteal phase. In contrast, there were no significant changes in IOP or HR. These findings indicate that choroidal thickness decreases during the mid-luteal phase in healthy Japanese women with normal menstrual cycles depending on systemic circulatory dynamics. However, since the difference in the SCT values between the late follicular and the mid-luteal phase is not large (7 μm), the menstrual cycle may have little influence on the interpretation of choroidal thickness data in clinical practice.

Retinal and Choroidal Changes Following Implantable Collamer Lens V4c Implantation in High Myopia Patients-A 1-Year Follow-Up Study.

This prospective study aimed to evaluate the impact of Visian Implantable Collamer Lens (ICL) V4c implantation on retinal and choroidal morphology in patients with high myopia. A total of 97 eyes from 52 high myopic patients who underwent ICL V4c implantation were followed up for 12 months. Preoperative and postoperative evaluations included comprehensive ophthalmic assessments and enhanced depth imaging optical coherence tomography (EDI-OCT) to analyze changes in central retinal thickness (CRT), retinal volume (CRV), choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), and choroidal vascular index (CVI). Repeated measures mixed-effects models were used for comparing pre- and postoperative measurement variables and exploring relationships among age, axial length (AL), spherical equivalent refraction (SER), and postoperative retinal and choroidal changes, with statistical significance set at p < 0.05. Follow-up assessments were conducted at various time points, with participation rates ranging from 21% to 98%. Baseline characteristics showed a median age of 26.7 years, -10.14 diopters of SER, and an AL of 27.44 mm. Throughout the 12-month follow-up, CRT and 3.0 mm CRV consistently increased compared to the baseline, with statistically significant rises observed at postoperative day 1, week 1, and month 12. Most ChT measurements, including subfoveal ChT, declined over the 12 months, except at postoperative 6 months. Horizontal and vertical TCA and LA values significantly increased throughout the follow-up, except for month 6. After surgery, both horizontal and vertical CVI parameters exhibited an increase compared to the baseline, with some changes reaching statistical significance. Correlation analysis performed by repeated measures mixed-effects models showed that no relationship was found between age, AL, and SER and changes in postoperative retinal parameters and CVI parameters. However, postoperative changes in ChT and choroidal area parameters showed a negative correlation with AL and a positive correlation with SER. Our research demonstrated that ICL V4c implantation resulted in noteworthy alterations in retinal and choroidal morphology over a 1-year follow-up period. Moreover, in patients with high myopia, individuals with longer AL and higher degrees of myopia exhibited more pronounced postoperative changes in the choroid and retina. Further studies with extended follow-up durations are necessary to comprehensively understand the long-term effects of ICL implantation on retinal and choroidal morphology and function.

In vivo quantification of human aqueous veins by enhanced depth imaging optical coherence tomography and optical coherence tomography angiography images.

To investigate the aqueous vein in vivo by using enhanced depth imaging optical coherence tomography (EDI-OCT) and optical coherence tomography angiography (OCTA). In this cross-sectional comparative study, 30 healthy participants were enrolled. Images of the aqueous and conjunctival veins were captured by EDI-OCT and OCTA before and after water loading. The area, height, width, location depth and blood flow of the aqueous vein and conjunctival vein were measured by Image J software. In the static state, the area of the aqueous vein was 8166.7±3272.7 µm2, which was smaller than that of the conjunctival vein (13 690±7457 µm2, P<0.001). The mean blood flow density of the aqueous vein was 35.3%±12.6%, which was significantly less than that of the conjunctival vein (51.5%±10.6%, P<0.001). After water loading, the area of the aqueous vein decreased significantly from 8725.8±779.4 µm2 (baseline) to 7005.2±566.2 µm2 at 45min but rose to 7863.0±703.2 µm2 at 60min (P=0.032). The blood flow density of the aqueous vein decreased significantly from 41.2%±4.5% (baseline) to 35.4%±3.2% at 30min but returned to 45.6%±3.6% at 60min (P=0.021). The structure and blood flow density of the aqueous vein can be effectively evaluated by OCT and OCTA. These may become biological indicators to evaluate aqueous vein changes and aqueous outflow resistance under different interventions in glaucoma patients.

Evaluation of the effect of sodium-glucose cotransporter-2 inhibitor treatment on choroidal vascular parameters in patients with type 2 diabetes mellitus

BackgroundTo evaluate the effect of sodium-glucose cotransporter-2 inhibitor treatment on choroidal vascular parameters in patients with type 2 diabetes mellitus (T2DM). MethodsTwenty eyes of 20 patients with T2DM without diabetic retinopathy and 20 eyes of 20 age- and sex-matched patients as the control group were included in the study. The patients were evaluated using enhanced depth imaging optic coherence tomography before treatment and at the third month of treatment. The choroidal images were binarized into luminal areas (LAs) and stromal areas (SAs). The choroidal vascularity index (CVI) was defined as the ratio of the LA to the total circumscribed choroid area (TCA). ResultsThe mean age of the patients was 56.65±8.41 years. The patients’ mean disease duration was 6.65±5.72 years, the mean HbA1c level was 8.89±1.62%, and the mean body mass index was 33.13±4.84 kg/m2. The subfoveal TCA, subfoveal LA, subfoveal SA, total TCA, total LA, and total SA values ​​of the patient group were found to be significantly lower than those of the control group (p = 0.006, p = 0.003, p = 0.028, p = 0.001, p = 0.001, and p = 0.006, respectively). There was a significant increase in the subfoveal TCA, subfoveal LA, subfoveal SA, subfoveal CVI, total TCA, total LA, and total SA values ​​after empagliflozin treatment compared to before empagliflozin treatment (p = 0.005, p = 0.003, p = 0.021, p = 0.032, p < 0.001, p < 0.001, and p = 0.001 respectively). ConclusionsEmpagliflozin provides an improvement in diabetic choroidal changes through its effect on choroidal vascularity parameters.

Choroidal structural changes in patients with early diabetic nephropathy

PurposeTo determine alterations of the choroidal thickness (CT) and the choroidal vascularity index (CVI) in patients with glomerular hyperfiltration, a marker of early diabetic nephropathy (DN). MethodsTwenty-two patients with type 2 diabetes (T2D) with glomerular hyperfiltration (early DN group) and 28 patients with T2D without DN (NDN group) were included in the study. Patients with diabetic retinopathy were excluded. Parameters including subfoveal CT, the subfoveal choroidal vascularity index (CVI), and total CVI were measured using spectral-domain enhanced depth imaging optical coherence tomography method. ResultsThe early DN group included 22 patients and the NDN group comprised 28 patients. The groups were similar in terms of age and sex (p>0.05). The CT values were statistically significantly lower in the early DN group than in the NDN group (p < 0.001). There was no significant difference between the early DN group and the NDN group in terms of total and subfoveal CVI (p>0.05). ConclusionThe choroidal thickness decreased in patients with T2D with glomerular hyperfiltration, but there were no differences in CVI when they were compared with patients with T2D without DN.

Evaluation of peripapillary choroidal vascularity index in young smokers

Purpose: This retrospective study aimed to compare the peripapillary choroidal vascularity index (CVI) between young smokers who smoked less than 5 packs/year and non-smokers. Methods: The study included 52 smokers and 67 non-smokers, and comprehensive eye examinations were performed on all participants. Axial lengths (AL) were measured, and peripapillary enhanced depth imaging optical coherence tomography (EDI-OCT) images were obtained and evaluated using the Open Source ImageJ software. The CVI, total choroidal area (TCA), luminal area (LA), stromal area (SA), and retinal nerve fibre layer (RNFL) quadrants were compared between the two groups. Results: The mean age of the smokers was 23.76 ± 1.84 years, and for non-smokers, it was 23.98 ± 2.18 years. The mean peripapillary CVI for smokers was 0.65 ± 0.08, and for non-smokers, it was 0.67 ± 0.03. No statistically significant difference in CVI was observed between the two groups. However, statistically significant differences were found in the temporal inferior (TI), temporal superior (TS), nasal inferior (NI), and nasal superior (NS) quadrants of the RNFL between the two groups (p < 0.05). There was no correlation between the number of packs/year and CVI values in the smoking group (r = 0.031, p = 0.826). Conclusion: The study revealed no significant difference in CVI among young smokers who smoked less than 5 packs/year compared to non-smokers. However, there was a statistically significant decrease in the TI, TS, NI, and NS quadrants of the RNFL in early-age smokers.

Comparison of the Choroid in Primary Open-angle and Angle-Closure Glaucoma Using Optical Coherence Tomography.

The current study highlights distinct choroidal alterations in primary open-angle and angle-closure glaucoma, underscoring the potential of choroidal vascularity index as a valuable indicator for understanding glaucoma pathogenesis. To evaluate choroidal structural changes in patients with primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) and healthy controls utilizing the choroidal vascularity index (CVI) and subfoveal choroidal thickness (SFCT) by enhanced depth imaging optical coherence tomography (EDI-OCT). This study was cross-sectional. A total of 171 eyes of 171 subjects, comprising 69 eyes with untreated POAG, 58 eyes with untreated PACG and 44 healthy eyes, were enrolled in this study. SFCT, luminal area (LA), stromal area (SA) and total choroidal area (TCA) were measured on EDI-OCT scans. The CVI parameter is calculated as the proportion of LA to TCA. This study included 69 POAG patients with a mean age of 51.4±13.3 years, 58 PACG patients with a mean age of 57.0±7.3 years, and 44 healthy subjects with a mean age of 51.11±10.7 years. The CVI in the POAG and PACG groups was significantly lower than that in the control group (P = 0.001 and P = 0.005, respectively), however not significantly different between the two glaucoma groups (P = 1.000). POAG eyes had significantly lower LA than PACG and controls (P = 0.014 and P = 0.049, respectively), while PACG eyes had significantly greater SA than controls (P = 0.041). The CVI of POAG and PACG eyes was significantly lower than that of normal eyes. A reduced LA was observed mainly in eyes with POAG, and an increased SA was observed mainly in eyes with PACG. The role of the choroid may differ between POAG and PACG eyes.

Evaluation of Arterial Stiffness and Subfoveal Choroidal Thickness in Patients with Coronary Slow Flow.

Coronary slow flow may not only affect the coronary arteries, but it may also be a vascular problem affecting the rest of the arterial system. The aim of this study was to determine peripheral arterial stiffness and the thickness of the choroid layer in patients with slow coronary flow. Fifty consecutive patients (age, 54.3 ± 11.4 years, 38 male) with coronary slow flow and 25 consecutive patients (age, 50.5 ± 9.9 years, 16 male) with normal coronary arteries both documented by coronary angiography were included. Arterial stiffness parameters were measured noninvasively using a Mobil-O-Graph arteriography system. The choroidal thickness was assessed using the enhanced depth imaging optical coherence tomography method. The patients with coronary slow flow had significantly higher peripheral systolic blood pressure, peripheral pulse pressure, central pulse pressure, and pulse wave velocity (PWV) and significantly thinner choroidal thickness compared to the controls. Thrombolysis in myocardial infarction frame count was positively correlated with PWV (r: 0.237, p = 0.041) and negatively correlated with choroidal thickness (r: -0.249, p = 0.031). There was also a negative correlation between PWV and mean choroidal thickness (r: -0.565, p < 0.001). Linear regression analysis showed that coronary slow flow was an independent predictor of both PWV and choroidal thickness when adjusted by age and sex. The acceleration of average peripheral arterial PWV with a thinning of choroidal thickness in patients with coronary slow flow may support the idea that this phenomenon may be a coronary presentation of a systemic microvascular disorder.

Ocular posterior segment microstructural and microvascular morphological changes in protein supplement-consuming bodybuilders

BackgroundTo determine the effects of protein supplement (whey protein powder (PP)) on retinal, choroidal and optic nerve head (ONH) microstructure and microvascular morphology in healthy bodybuilders. MethodsThis cross-sectional study included 23 male adults (consumers, 23 right eyes) who had been routinely consuming whey PP for bodybuilding purposes for ≥ 3 months, and 21 age- and gender-matched healthy volunteers (non-consumers, 21 right eyes) who also attended the gym but did not consume any nutritional supplements. Participants underwent standard ocular exams, enhanced depth imaging optical coherence tomography (EDI OCT), and optical coherence tomography angiography (OCTA) after ≥ 8 h of rest and fasting. ResultsWhey PP was consumed for a median of 9.5 (6–12) months. Whey PP consumers had a median age of 22 (21–22) years, while non-consumers had 21 (20–22) years (p = 0.067). Whey PP consumers had greater microstructural thickness than non-consumers, with subfoveal choroidal thickness (301.40 ± 38.91 versus 278.12 ± 33.58 µm; p = 0.035) being significantly different but not central macular thickness (270.55 ± 24.60 versus 265.85 ± 12.44 µm; p = 0.402). Despite a non-significant difference in superficial and deep capillary plexus vascular densities (VDs), whey PP consumers had relatively lower VDs than non-consumers in all macular regions (p > 0.05). Despite this, whey PP consumers displayed greater ONH VDs, as well as higher global RNFL thickness (116.75 ± 10.41 versus 114.50 ± 11.70 µm) than non-consumers (p > 0.05). ConclusionProtein supplements, particularly whey PPs, appear to be associated with different changes in the retina and choroid, as well as ONH microstructural and microvascular morphology, implying that paying attention to these clinical aspects when performing ocular tests in bodybuilders who consume nutritional supplements could be critical.

Change in Subfoveal Choroidal Thickness following Cataract Surgery Imaged with Enhanced Depth Imaging Optical Coherence Tomography.

Due to its invasive nature, cataract surgery can lead to inflammatory processes in the posterior segment, which can result in prolonged recovery times, reduced functional outcomes, and late-onset complications. The aim of the current study was to identify wherever phacoemulsification parameters play a role in choroidal thickness change following cataract surgery. This prospective single-center study enrolled 31 patients (31 eyes) scheduled to undergo routine cataract surgery. Patients with previous ocular surgeries, pathologies or general disorders affecting vision were excluded. Patients were examined preoperatively, as well as 1, 4, and 12 weeks after surgery. Corrected distance visual acuity (CDVA), intraocular pressure (IOP) as well as cumulative dissipated energy (CDE), ultrasound time (UT), and fluids used during surgery were recorded. Subfoveal choroidal thickness was measured manually by two masked independent experts using enhanced depth imaging (EDI) optical coherence tomography (OCT). Furthermore, cataract density was automatically calculated using a custom MATLAB script and an anterior segment OCT. Subfoveal choroidal thickness increased significantly (p < 0.001, Student's paired sample t-test) and continuously during the 12-week-long follow-up period. Both the nuclear lens density and the improvement in CDVA correlated significantly with this increase (r = 0.413, p = 0.021 and r = 0.421, p = 0.018, respectively). Neither the CDE (r = 0.334, p = 0.071), the UT (r = 0.102, p = 0.629), the amount of fluid used (r = 0.237, p = 0.27) nor the decrease in IOP (r = - 0.197, p = 0.288) showed any significant correlation with the choroidal swelling. Cataract surgery leads to an increase in subfoveal choroidal thickness. While no statistically significant correlation to the phacoemulsification parameters could be established, this might be because of a selection bias due to the technological constraints of the OCT. Nevertheless, the choroid might play a central role in early- and late-onset complications.

Evaluation of choroidal thickness and choroidal vascularity index in patients with Crimean-Congo hemorrhagic fever.

This study aimed to compare choroidal thickness parameters between patients diagnosed with Crimean-Congo hemorrhagic fever (CCHF) and healthy individuals using spectral domain optical coherence tomography. The right eyes of 27 individuals diagnosed with CCHF and 27 healthy subjects were included in this study. CCHF cases were assessed based on a history of tick bites and hospitalization. Choroidal thickness was measured using enhanced depth imaging optical coherence tomography. Measurements of choroidal thickness were taken at 5 different points, including the subfoveal quadrant and the fovea up to 2000μm with 1000μm intervals in the temporal and nasal quadrants. Choroidal vascular index (CVI) was calculated as the ratio of luminal area (LA) to total choroidal area (TCA) at the macula's total area and at 1500μm from the center (CVI and CVI1500). Choroidal thickness in the CCHF group was found to be thicker in each quadrant compared to the control group, with the subfoveal and nasal quadrants showing significantly greater thickness. TCA, stromal area, and LA were significantly higher in the CCHF group, while no significant difference was observed in CVI and CVI1500. The findings of this study suggest that CCHF disease may have an impact on the choroidal structure.

Optic Nerve Head, Peripapillary and Macular Microvascular Characteristics in Patients with Unilateral Pseudoexfoliation Glaucoma.

In unilateral pseudoexfoliation glaucoma (PEXG), there may be decreased choroidal vascularity index (CVI), radial peripapillary capillary plexus' perfusion and flow. CVI may also be reduced in fellow eyes, suggesting that PEXG is bilateral disease. Evaluation of peripapillary and macular choroidal microvascularity and radial peripapillary capillary plexus (RPC) in both eyes with unilateral pseudoexfoliation glaucoma (PEXG) and healthy eyes. Ninety-six eyes of 48 patients with unilateral PEXG (PEX (+): 48 eyes with PEXG; PEX (-): 48 eyes without PEX) and the right eyes of 45 age- and sex-matched healthy controls were included in the study. Choroidal vascular index (CVI) was calculated on enhanced depth imaging optical coherence tomography (EDI-OCT) scans. RPC vascular layer were evaluated by OCT-Angiography (OCTA). Macular CVI (mCVI), temporal and nasal peripapillary CVI (pCVI) was significantly decreased in the PEX (+) compared to the PEX (-) and control group (P<0.05 for all). While there was a significant difference between PEX (-) and the control group in terms of mCVI and temporal pCVI, there was no significant difference between the two groups in terms of nasal pCVI (P=0.008, P=0.036 and P=0.604, respectively). There was a significant difference in perfusion density (PD) and flux index (FI) between PEX (+) group, PEX (-) group and control group in all quadrants and average value (P<0.05 for all). Although the PD and FI values in all quadrants and average values of the PEX (-) group were lower than the control group, this difference was not significant. CVI in the macula and peripapillary region tends to decrease in eyes with PEXG. Similarly, PD and FI were lower in eyes with PEXG. Low mCVI and temporal pCVI can also be seen in eyes without PEX.

Effects of Sinovac-Coronavac and Pfizer-BioNTech mRNA vaccines on choroidal and retinal vascular system

PurposeTo evaluate the effects of Sinovac-Coronavac and Pfizer-BioNTech mRNA vaccines on choroidal and retinal vascular system using enhanced depth imaging optical coherence tomography (EDI-OCT) and optical coherence tomography angiography (OCTA). MethodsIn this prospective cross-sectional study, 63 healthy participants (29 with Pfizer-BioNTech, 34 with Sinovac-CoronaVac) were evaluated after the first dose of vaccination. Vessel density (VD) of the superficial (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) were measured with OCTA. Choroidal thickness (CT) were measured with EDI-OCT. Measurements were performed at the 2nd week and the 4th week after vaccinations and compared to pre-vaccination values. ResultsRegarding Pfizer-BioNTech vaccination, CT in the subfoveal and nasal region significantly increased between the pre-vaccination and post-vaccination 2nd week and then significantly decreased to pre-vaccine values at 4th week. The SCP-VD (whole image, fovea, parafovea, perifovea temporal) variables showed a significant decrease at 2nd week. The DCP-VD inferior hemi, parafovea inferior hemi, parafovea inferior variables demonstrated a significant decrease at 2nd week. The perifovea DCP-VD variables also showed a significant decrease at 2nd week, and these variables returned to pre-vaccination values after 4 weeks. The CC-VD variables showed a significant decrease between pre-vaccine and 2nd week post-vaccination. Regarding the Sinovac-CoronaVac vaccination, there was no statistically significant difference in CT and VD values before and after vaccination (p> 0.05). ConclusionOur study showed significant alterations in retinal vascular density and CT for the Pfizer-BioNTech vaccine at the 2nd week, and these parameters became compatible with pre-vaccination values at the 4th week. In contrast, no differences were observed after the Sinovac-Coronovac vaccination.

Concomitant paracentral acute middle maculopathy and acute macular neuroretinopathy in eyes post-blunt trauma.

To analyze the imaging characteristics and the clinical course of patients showing concomitant paracentral acute middle maculopathy (PAMM) and acute macular neuroretinopathy (AMN) post-blunt trauma. PAMM and AMN lesions post-blunt trauma diagnosed on enhanced depth imaging optical coherence tomography (EDI-OCT) were recruited for the study. : Thirteen eyes of 13 individuals with a history of blunt trauma were included in the study, of whom 11 (85%) were males. Mean age of the patients was 33.62 (range 16-67) years. Mean visual acuity at presentation and the last visit was 1.67 log of minimum angle of resolution (logMAR) and 0.82 logMAR, respectively. Mean interval between trauma and imaging was 5.08 (range 1-15) days. All patients had unilateral involvement, with the right eye being involved in 10 patients (77%). All patients had concomitant PAMM and AMN lesions. : Presence of coincident PAMM and AMN suggests a common pathophysiologic etiology, but the description of concomitant PAMM and AMN in the setting of blunt trauma to eye is hitherto unreported. Identifying AMN in a setting of PAMM requires meticulous examination of the OCT and OCTA images. It can be a cause of suboptimal visual recovery in such eyes.