Retinal Vascular Changes Research Articles

A Case Report of Ocular Manifestation of Rickettsial Infection- A Rare Vision Threatening Gram Negative Bacteria Causing Chorioretinitis

Rickettsioses are emergent and resurgent arthropod vector borne diseases due to obligate intracellular small gram-negative
 bacteria. Most of them are transmitted to humans by the bite of infected arthropods, such as ticks. Ocular involvement is common,
 including conjunctivitis, keratitis, anterior uveitis, panuveitis, retinitis, retinal vascular changes, and optic nerve involvement.
 Though rickettsiosis is common in India, there is paucity of rickettsial retinitis (RR) reports from India. Moreover, rickettsial
 sub-types and their association with retinitis have not been studied.Ocular rickettsial infection may be a part of systemic rickettsial
 infection which is mainly autoimmune in nature so treatment is mostly based on steroids and antibiotics.
 We report the case of a 36 year old male native of North India.

Determination of the association between excessive intake of Rasa and Retinal vascular changes in Pregnancy-Induced Hypertension- A Pilot Study

Background: Pregnancy-induced hypertension (PIH) is a hypertensive disorder in pregnancy that occurs in the absence of other causes of elevated blood pressure. There are many complications documented for PIH and associated retinal vascular changes in one of them. During pregnancy if proper antenatal care along with diet is not followed, patient may land into complications like PIH related retinopathy. Aim: To determine the retinal changes in pregnancy induced hypertension (PIH) and any association between the retinal changes and excess intake of specific Rasa. Methods: All the patients admitted in ward with diagnosis of PIH were included in this study. Age, race, gravida, gestation period, blood pressure, and proteinuria along with dietary habit were noted from the case records. After taking history for any eye symptoms, fundus examination was done after dilating the pupils with direct ophthalmoscope in the ward itself. All the findings were noted on a data sheet, and were analyzed. Results: A total of 24 patients of PIH were examined. Majority were urban (75%) and remaining are from rural area (25%). The majority of patients are from 24-28 years age group followed by below 20 years age group. The gestation period ranged from 20 weeks to 38 weeks; 16 (66.6%) were primi gravida. Nineteen (79.1%) patients had mild preeclampsia, 03 (12.5%) had severe preeclampsia and 2 (8.33%) had eclampsia. Retinal changes (hypertensive retinopathy) were not seen in any of these patients Haemorrhages or exudates or retinal detachment were not seen in any patient. There was no association of retinal changes and Rasa Sevan a found in present pilot study. Conclusion: Retinal changes were not seen in any of the patients with PIH in present study sample and there was not found to be associated with excess intake of specific Rasa and severity of the disease. Fundus examination is necessary in assessment of the PIH patient.

Ocular Status with Chronic Kidney Disease- a Hospital Based Two Year Study on 150 Cases

Background: Chronic Kidney Disease (CKD) is a growing public health problem affecting millions of people worldwide. Along with its well-known systemic effects, CKD has been associated with various ocular abnormalities, including uveitis, macular edema, and retinal vascular changes. Early detection and management of these ocular complications can prevent significant visual loss and improve the quality of life of patients with CKD. This highlights the importance of regular ophthalmic examinations as part of the comprehensive management of CKD. The aim of this study was to evaluate the ocular status of chronic kidney disease. Material Methods: This was an observational study. The present study was conducted on 150 Patients attending the Department of Ophthalmology at Dr. Sirajul Islam Medical College and Hospital Ltd, Dhaka, Bangladesh. The duration of the study was 2 years. All collected data was entered in MS Excel and Statistical analysis was done using the SPSS-24 version. Results: The study analyzed a population between the ages of 40-59 years, with a slight majority of women (52.67%) and moderate CKD (64.00%). The most common cause of CKD in the population was hypertension and diabetes (52.00%). 66.67% of 300 eyes had good vision (6/18 or better), while the remainder had impaired or legally blind vision (increasing as the severity of CKD increases). Ocular anterior segment findings showed that lid oedema and conjunctival pallor were present in 3.5% and 56.9% of the eyes, respectively. Dry eyes and cataract were present in 5.6% and 11.1% of the eyes, respectively. Hypertensive retinopathy was present in 48.00% of eyes in the moderate CKD group, and diabetic retinopathy was present in 32.00% of eyes in the severe and end-stage CKD groups. Maculopathy and vitreous hemorrhage were present in 12.67% and 6.33% of eyes in the end-stage CKD group. Of the 100 eyes with poor or blind visual acuity, 24 (24%) were affected by Maculopathy and 21 (21%) by Cystoid Macular Edema. The causes of visual impairment were also listed with their corresponding percentage. Conclusion: In CRF patients, eye exams can detect ocular problems. Early treatment prevents negative outcomes and those with a history of abnormal renal function need close monitoring due to increased risk of vision loss. Awareness of ocular complications is important, as well as thorough eye exams and control of diabetes and hypertension for maintaining eye health.

En-face widefield optical coherence tomography angiography for understanding vascular networks changes in two cases of acute retinal necrosis

PurposeThe present study assesses the utility of en-face widefield optical coherence tomography angiography (OCTA) imaging for evaluating the retinal vascular network during the course of treatment in acute retinal necrosis(ARN).ObservationsOCTA images of two cases of acute retinal necrosis were analyzed. Case 1 was a 15-year-old male with visual crowding in his right eye who had best-corrected visual acuity of 16/20 and intraocular pressure of 25 mmHg in his right eye on initial evaluation. Case 2 was a 57-year-old male with visual crowding in his left eye who had best-corrected visual acuity of 20/20 in his left eye on initial examination and intraocular pressure of 19.3 mmHg.In both patients, dynamic changes could be tracked by en-face ultra-widefield OCTA imaging before and up to 1 year after surgical treatment. The images showed arteriovenous anastomosis and the nonperfused area on the surface of the retina.Conclusions and importanceEn-face widefield OCTA is useful for monitoring the structure of retinal vessels over time in acute retinal necrosis. Wide-angle OCTA is used to non-invasively examine retinal vascular dynamic changes in ARN. OCTA artifacts due to intraocular inflammation appeared, making interpretation difficult. These will remain as issues in the future. It seems difficult for a while to completely replace FA due to the problem of image clarity.

Intraoperative optical coherence tomography angiography for intraocular surgery

Purpose: To evaluate the feasibility of an intraoperative optical coherence tomography angiography (iOCTA) system integrated with a surgical microscope, and further investigate the real-time retinal vascular change in intraocular pressure fluctuation during surgery in rabbits.Methods: The feasibility of this system was confirmed through fundus angiography imaging in 12 rabbit eyes during simulated surgeries in 4 groups, 30 mmHg infusion pressure (IP), 60 mmHg IP, 100 mmHg IP, and control groups. The eyes were removed after seven days. Retinal ganglion cell (RGC) damage was analyzed histologically.Results: The OCTA technique can acquire images of retinal capillaries in rabbit eyes and quantitatively analyzing the vessel density. In the 30 mmHg IP group, there was no significant difference in the retinal vasculature during the operation. The OCTA signal and the RGCs decreased significantly in the 60 and 100 mmHg groups.Conclusions: The system can real-timely monitor the human retinal vasculature in high-resolution images and help surgeons to make decision during intraocular surgery.

Optic disc and retinal vessel densities assessment by optical coherence tomography angiography in patients with keratoconus.

This study aimed to evaluate retinal and optic disc vascular changes in patients with keratoconus (KC) using optical coherence tomography angiography (OCTA). Thirty-two eyes of 22 patients with KC and 24 eyes of 24 age- and sex-matched healthy controls were included in this study. Corneal topography and OCTA were performed. Quantitative vessel density of the macular superficial capillary plexus (SCP), macular deep capillary plexus (DCP), and radial peripapillary capillaries (RPC); choriocapillaris flow area; and choroidal thickness were compared between the KC and control groups. SCP and DCP vessel densities showed a significant reduction in the KC group compared to that in the control group (p < 0.001 and p < 0.001 in the whole image and parafovea, respectively). Choriocapillaris flow area was significantly higher in patients with KC than in the control group (p=0.003). The foveal avascular zone area did not significantly differ between the two groups (p=0.949). RPC inside disc vessel density was significantly decreased in the KC group compared to that in the control group (p < 0.001). This study revealed important macular, choroidal, and optic disc vessel densities changes in patients with KC. Macular whole vessel density and parafoveal vessel density of the SCP and DCP decreased, while choriocapillaris flow area increased in patients with KC.

Macular vessel density in the superficial plexus is not associated to cerebrospinal fluid core biomarkers for Alzheimer's disease in individuals with mild cognitive impairment: The NORFACE cohort.

Optical coherence tomography angiography (OCT-A) is a novel method in the dementia field that allows the detection of retinal vascular changes. The comparison of OCT-A measures with established Alzheimer's disease (AD)-related biomarkers is essential to validate the former as a marker of cerebrovascular impairment in the AD continuum. We aimed to investigate the association of macular vessel density (VD) in the superficial plexus quantified by OCT-A with the AT(N) classification based on cerebrospinal fluid (CSF) Aβ1-42, p181-tau and t-tau measurements in individuals with mild cognitive impairment (MCI). Clinical, demographic, ophthalmological, OCT-A and CSF core biomarkers for AD data from the Neuro-ophthalmology Research at Fundació ACE (NORFACE) project were analyzed. Differences in macular VD in four quadrants (superior, nasal, inferior, and temporal) among three AT(N) groups [Normal, Alzheimer and Suspected non-Alzheimer pathology (SNAP)] were assessed in a multivariate regression model, adjusted for age, APOE ε4 status, hypertension, diabetes mellitus, dyslipidemia, heart disease, chronic obstructive pulmonary disease and smoking habit, using the Normal AT(N) group as the reference category. The study cohort comprised 144 MCI participants: 66 Normal AT(N), 45 Alzheimer AT(N) and 33 SNAP AT(N). Regression analysis showed no significant association of the AT(N) groups with any of the regional macular VD measures (all, p > 0.16). The interaction between sex and AT(N) groups had no effect on differentiating VD. Lastly, CSF Aβ1-42, p181-tau and t-tau measures were not correlated to VD (all r < 0.13; p > 0.13). Our study showed that macular VD measures were not associated with the AT(N) classification based on CSF biomarkers in patients with MCI, and did not differ between AD and other underlying causes of cognitive decline in our cohort.

Retinal Blood Vessel Analysis Using Optical Coherence Tomography (OCT) in Multiple Sclerosis

Background: Both greater retinal neurodegenerative pathology and greater cardiovascular burden are seen in people with multiple sclerosis (pwMS). Studies also describe multiple extracranial and intracranial vascular changes in pwMS. However, there have been few studies examining the neuroretinal vasculature in MS. Our aim is to determine differences in retinal vasculature between pwMS and healthy controls (HCs) and to determine the relationship between retinal nerve fiber layer (RNFL) thickness and retinal vasculature characteristics. Methods: A total of 167 pwMS and 48 HCs were scanned using optical coherence tomography (OCT). Earlier OCT scans were available for 101 pwMS and 35 HCs for an additional longitudinal analysis. Segmentation of retinal vasculature was performed in a blinded manner in MATLAB's optical coherence tomography segmentation and evaluation GUI (OCTSEG) software. Results: PwMS has fewer retinal blood vessels when compared to HCs (35.1 vs. 36.8, p = 0.017). Over the 5.4 year follow up, and when compared to HCs, pwMS has a significant decrease in number of retinal vessels (average loss of -3.7 p = 0.007). Moreover, the total vessel diameter in pwMS does not change when compared to the increase in vessel diameter in the HCs (0.06 vs. 0.3, p = 0.017). Only in pwMS is there an association between lower RNFL thickness and fewer retinal vessel number and smaller diameter (r = 0.191, p = 0.018 and r = 0.216, p = 0.007). Conclusions: Over 5 years, pwMS exhibit significant retinal vascular changes that are related to greater atrophy of the retinal layers.

The effect of palm oil-derived tocotrienol-rich fraction in preserving normal retinal vascular diameter in streptozotocin-induced diabetic rats.

Angiogenesis in diabetic retinopathy (DR) is associated with increased retinal expression of angiopoietin-2 (Ang-2) and protein kinase C (PKC). Tocotrienol-rich fraction (TRF) has been shown to reduce the expression vascular endothelial growth factor (VEGF) in several experimental models. However, its effect against other angiogenic markers such as Ang-2 and PKC in rat modelof diabetes remains unknown. Therefore, we investigated the effect of TRF on the retinal vascular changes and Ang-2 and PKC expressions in rats with streptozotocin (STZ)-induced DR. Sprague-Dawley rats were divided into normal control rats (N) which received vehicle, and diabetic rats which either received vehicle (DV) or 100mg/kg of TRF (DT). Diabetes was induced with intraperitoneal injection of STZ (60mg/kg body weight). Treatments were given orally, once daily, for 12weeks after confirmation of hyperglycaemia. Fundus photographs were captured at baseline, 6- and 12-week post-STZ injection and average diameter of retinal veins and arteries were measured. At 12-week post-STZ injection, rats were euthanised, and retinae were collected for measurement of Ang-2 and PKC gene and protein expressions. Retinal venous and arterial diameters were significantly greater in DV compared to DT at week 12 post-STZ injection (p < 0.001 and < 0.05, respectively). The vesseldiameter measurements in DT were comparable to N and this effect of TRF was associated with significantly lower Ang-2 and PKC gene and protein expressions compared to DV. Oral TRF reduces the expression of retinal angiogenic markers and preserves the retinalvascular diameter of rats withSTZ-induced DR.

Retinal Vascular Changes in Alzheimer's Dementia and Mild Cognitive Impairment: A Pilot Study Using Ultra-Widefield Imaging.

Retinal microvascular abnormalities measured on retinal images are a potential source of prognostic biomarkers of vascular changes in the neurodegenerating brain. We assessed the presence of these abnormalities in Alzheimer's dementia and mild cognitive impairment (MCI) using ultra-widefield (UWF) retinal imaging. UWF images from 103 participants (28 with Alzheimer's dementia, 30 with MCI, and 45 with normal cognition) underwent analysis to quantify measures of retinal vascular branching complexity, width, and tortuosity. Participants with Alzheimer's dementia displayed increased vessel branching in the midperipheral retina and increased arteriolar thinning. Participants with MCI displayed increased rates of arteriolar and venular thinning and a trend for decreased vessel branching. Statistically significant differences in the retinal vasculature in peripheral regions of the retina were observed among the distinct cognitive stages. However, larger studies are required to establish the clinical importance of our findings. UWF imaging may be a promising modality to assess a larger view of the retinal vasculature to uncover retinal changes in Alzheimer's disease. This pilot work reports an investigation into which retinal vasculature measurements may be useful surrogate measures of cognitive decline, as well as technical developments (e.g., measurement standardization), that are first required to establish their recommended use and translational potential.

Polypoidal Choroidal Vasculopathy Mimicking as Central Serous Chorioretinopathy

Polypoidal choroidal vasculopathy (PCV) is considered one of the disease entities in the pachychoroid spectrum sharing the common finding of abnormally thickened choroid with Central serous chorioretinopathy (CSCR). Polypoidal choroidal vasculopathy (PCV) is a vascular malformation of the choroid, comprising a network of branching vessels of varying sizes that produce aneurysmal-like enlargements. This disease is generally observed in the macular area. Central serous chorioretinopathy is a retinal disorder characterized by localized serous detachment of the macula. It is secondary to retinal pigment epithelial decomposition and choroidal vascular changes. Fundus photography, optical coherence tomography (OCT), Fundus fluorescein angiography, and Indocyanine green angiography (ICG) aid in the diagnosis and differentiation between these two entities. Here, we report a case of middle aged female presented initially with clinical features suggestive of CSCR and later turned out to be a case of PCV.

Imaging techniques for ocular neoplasia

Background: Novel ocular imaging modalities have greatly impacted the diagnosis and management of different types of ocular neoplasia. In this narrative review, we summarize the practical features of popular and novel imaging modalities for ocular tumors.&#x0D; Methods: Four databases, including PubMed/MEDLINE, Web of Science, Scopus, and Google Scholar, were searched from January 1, 2000 to August 31, 2022. Articles reporting different imaging modalities for diagnosing or monitoring treatment responses of ocular tumors were extracted using various combinations of the following keywords: ocular neoplasia, positron emission tomography or PET, single-photon emission computed tomography or SPECT, optical coherence tomography or OCT, OCT angiography or OCTA, computed tomography or CT, ultrasonography or US, ultrasound biomicroscopy or UBM, and magnetic resonance imaging or MRI.&#x0D; Results: Various ocular imaging modalities had different accuracies as adjunctive tools for detecting or managing ocular tumors. Anterior ultra-high-resolution optical coherence tomography (OCT) could be used to evaluate images with &lt; 5-µm resolution. OCT angiography provided deeper insight into retinal vascular changes associated with the malignant transformation of choroidal melanoma. OCT in children altered the diagnosis of suspicious retinoblastoma in 3% of the cases and treatment plan in 11% of the cases. While positron-emission tomography (PET)/computed tomography (CT) allowed the detection of metastatic lesions of choroidal melanoma by full-body scanning, single-photon emission CT was more sensitive compared to PET in detecting choroidal melanoma. Ultrasound biomicroscopy, with an accuracy exceeding 92.5%, could detect retinal calcification in lesions measuring 2–3 mm. Magnetic resonance imaging (MRI) had better contrast compared to ultrasound biomicroscopy and higher sensitivity compared to CT in detecting post-laminar optic nerve invasion. However, MRI had a lower spatial resolution compared to OCT. Further development of imaging modalities and their application in drug development would improve the treatment of ocular tumors.&#x0D; Conclusions: Although diagnosing ocular tumors depend on clinical characteristics, innovations in ocular imaging have enabled early diagnosis and timely, appropriate management of ocular neoplasia, which are conducive to favorable visual outcomes and increased life expectancy. Further systematic reviews and meta-analyses of primary studies focusing on a specific imaging modality in ocular neoplasia could precisely determine the diagnostic accuracy of each imaging modality to better guide eye practitioners with efficient diagnostic or therapeutic approaches for these sight- or life-threatening entities. Imaging modalities may play a major role in drug development in the future.

Retinal vascular changes in response to hypoxia

AbstractPurpose: Increased tortuosity and engorgement of retinal vasculature are recognized physiological responses to hypoxia. This can lead to high‐altitude retinopathy (HAR), which is a pathology seen in unacclimatised individuals at altitude. It typically features asymptomatic flame haemorrhages, but incidence reports are highly variable and our understanding of the aetiological mechanisms remains incomplete. This study aimed to evaluate retinal vascular changes throughout an expedition to 4167 metres.Methods: 10 healthy participants summitted Mount Toubkal, Morocco. Fundus images were taken on a handheld camera pre‐departure, daily throughout the expedition, and one‐month post‐return. Diameter and tortuosity of four vessels was assessed, in addition to vessel density and the presence of HAR.Results: Significant (p ≤ 0.05) increases in tortuosity and diameter were observed in some vessels on high‐altitude exposure days. There was a significant increase in vessel density on summit day only.Conclusions: This is the first study to report increased vessel density and no incidence of HAR. These results are likely attributable to relatively low altitude exposure, a conservative ascent profile, and the young, healthy demographic profile of participants. However, the study is limited by its small sample size, environmental confounding factors and semi‐subjective diameter measurements. Physiological but not pathological changes were seen in this cohort, which gives insight to the state of the cerebral vasculature throughout this expedition and builds on current understanding of retinal vascular changes in hypoxia. Future work must include daily retinal images of larger sample sizes at higher altitude and take steps to mitigate against environmental confounders. This work is relevant to altitude tourists, patients with diabetic retinopathy or retinal vein occlusion, and critically ill patients at sea level.

Multiple sclerosis and occlusive retinal vasculitis: A case series

AbstractPurpose: Retinal vascular changes are a common finding in patients with multiple sclerosis (MS). While simple peripheral retinal periphlebitis is by far the most frequent manifestation, a spectrum exists that ranges up to the presence of proliferative retinal vasculitis.Methods: Case series of four patients with occlusive retinal vasculitis.Results: Three patients presented with complaints of visual loss and ocular discomfort: a 26‐year‐old man presented with vitreous inflammation, vitreous haemorrhage, macular edema and papillitis; a 44‐year‐old woman presented with intermediate uveitis and macular edema; and a 25‐year‐old woman presented with granulomatous panuveitis, papillitis and foveolar serous detachment. A fourth patient was addressed because of abnormal eye movements detected during a work‐up for dizziness. Examination revealed bilateral internuclear ophthalmoplegia with adduction lag. He had no visual complaints other than subtle floaters in the left eye. Anterior segment examination showed no signs of inflammation, whereas vitreous snowballs were present. Fluorescein angiography revealed occlusive retinal vasculitis in all patients, resulting in active neovascularization in two patients with vitreous haemorrhage in one of them. All patients required retinal laser photocoagulation. Extensive work‐up revealed multiple sclerosis as the underlying disease in three patients; the remaining patient had already been diagnosed with MS at the time of presentation. Nevertheless, additional work‐up was performed in this patient to exclude other possible causes.Conclusions: Occlusive retinal vasculitis is a rare manifestation in patients with MS and may result in neovascularization, vitreous haemorrhage, retinal detachment and neovascular glaucoma. MS should therefore be considered in the differential diagnosis of ischemic retinal disease. In addition, one should be alert for signs of retinal vasculitis in patients with MS, as it can present with few or no symptoms.

The relationship of retinal vessel calibres with cardiovascular risk factors in apparently healthy young eyes

AbstractPurpose: Although retinal vascular calibre has been linked to increased cardiovascular (CV) risk, it remains unclear whether retinal vascular morphologic changes are already evident in young adults and correlate with modifiable CV risk factors. The purpose of this study was to explore the relationship of retinal arteriolar and venular calibre with CV risk factors and ocular parameters in healthy young subjects.Methods: A cross‐sectional study was performed in 52 apparently healthy subjects (mean 21.6 ± 2.2 years of age). Retinal vascular calibres were measured from fundus photographs using semi‐automated imaging software and expressed as central retinal arteriolar (CRAE) or venular (CRVE) equivalent and arterio‐venous ratio (AVR). CV risk factors and ocular parameters were assessed. Forward stepwise multiple linear regression analysis was used to detect the independent relationship between retinal vascular calibre and CV and ocular parameters.Results: Means for CRAE and CRVE were 191 ± 15.4 μm and 209 ± 15.8 μm respectively. The mean CRAE but not CRVE was significantly higher in women than in men (p = 0.009). Systolic blood pressure (SBP) and spherical equivalent were significant contributing factors to CRAE (SBP: p &lt; 0.001; SE: p = 0.021). However, CRVE was not significantly predicted by CV risk factors or ocular parameters. SBP was the only one independent contributor to AVR (p = 0.018).Conclusions: In young adults, higher SBP was found to be related to narrower retinal arterioles, but not to retinal venules. Sex and other confounding CV or ocular factors had no effect on the relationship of SBP and retinal vessel calibre.

Swept‐source optical coherence tomography angiography in toxoplasmic retinochoroiditis

AbstractPurpose: To describe optical coherence tomography angiography (OCTA) findings in eyes with active and scarred toxoplasmic retinochoroiditis.Methods: OCTA scans in active (25 eyes) and scarred (17 eyes) retinochoroiditis were retrospectively reviewed at Fattouma Bourguiba University Hospital, Monastir, Tunisia.Results: In active lesions, OCTA findings included a non‐detectable flow signal area in retinal vascular plexuses and choriocapillaris in all 25 eyes (100%), an abnormal intraretinal vascular process in two eyes (8%), and an associated area of retinal flow deficit secondary to branch retinal artery occlusion in one eye (4%). In scarred lesions, OCTA findings included a flow deficit area in retinal vascular plexuses and choriocapillaris in all 17 eyes (100%), a visibility of larger deeper choroidal vessels at the level of choriocapillaris in nine eyes (53%), and a well‐defined intraretinal vascular network in one eye (5.9%). Peripapillary scars were associated on OCTA with wedge‐shaped loss of radial peripapillary capillaries with corresponding localized retinal nerve fibre layer defect and visual field loss.Conclusions: OCTA allows to non‐invasively detect retinal and choroidal vascular changes in active and scarred toxoplasmic retinochoroiditis.

Comparison of Retinal Imaging Techniques in Individuals with Pulmonary Artery Hypertension Using Vessel Generation Analysis.

(1) Background: Retinal vascular imaging plays an essential role in diagnosing and managing chronic diseases such as diabetic retinopathy, sickle cell retinopathy, and systemic hypertension. Previously, we have shown that individuals with pulmonary arterial hypertension (PAH), a rare disorder, exhibit unique retinal vascular changes as seen using fluorescein angiography (FA) and that these changes correlate with PAH severity. This study aimed to determine if color fundus (CF) imaging could garner identical retinal information as previously seen using FA images in individuals with PAH. (2) Methods: VESGEN, computer software which provides detailed vascular patterns, was used to compare manual segmentations of FA to CF imaging in PAH subjects (n = 9) followed by deep learning (DL) processing of CF imaging to increase the speed of analysis and facilitate a noninvasive clinical translation. (3) Results: When manual segmentation of FA and CF images were compared using VESGEN analysis, both showed identical tortuosity and vessel area density measures. This remained true even when separating images based on arterial trees only. However, this was not observed with microvessels. DL segmentation when compared to manual segmentation of CF images showed similarities in vascular structure as defined by fractal dimension. Similarities were lost for tortuosity and vessel area density when comparing manual CF imaging to DL imaging. (4) Conclusions: Noninvasive imaging such as CF can be used with VESGEN to provide an accurate and safe assessment of retinal vascular changes in individuals with PAH. In addition to providing insight into possible future clinical translational use.

Correlation analysis between foveal avascular zone and near peripheral retinal hypoperfusion in multiple sclerosis: a wide field optical coherence tomography angiography study.

The identification of non-invasive biomarkers to investigate and monitor retinal structural and vascular changes in multiple sclerosis (MS) represents an interesting source of debate. Until now optical coherence tomography angiography (OCTA) evaluated the foveal avascular zone (FAZ) and areas of retinal non-perfusion only in the macular region in MS patients. It could be interesting to identify possible biomarkers, useful in assessing the ischemic areas also in the near peripheral retina, since FAZ enlargement and the areas of peripheral retinal non-perfusions share common pathogenic processes. In this cross-sectional study, we investigated the correlation between the FAZ area and retinal vessel density (VD) in the near peripheral retina by new wide-field optical coherence tomography angiography (OCTA) in patients affected by relapsing-remitting multiple sclerosis (RR-MS). Moreover, we compared the FAZ area and the VD of superficial and deep capillary plexuses in the fovea region and in the near peripheral retina (6.4 × 6.4 mm) between RR-MS patients and healthy controls by means of a Solix full-range OCTA. Last, we also detected the changes in structural OCT parameters (ganglion cell complex and retinal nerve fiber layer). Thirty-three eyes of 33 RR-MS patients and 35 eyes of 35 healthy controls were enrolled. RR-MS patients showed a lower VD in the superficial capillary plexus and a significant increase in the FAZ area compared with controls. The deep capillary plexus revealed a reduced VD although not statistically significant in patients with respect to controls. In the patients' group, the FAZ area showed significantly negative correlations with VD of superficial capillary plexuses in the foveal and whole region, while the FAZ area did not negatively correlate with the VD of the deep capillary plexus. The significant correlations among OCTA parameters could demonstrate the FAZ area as a possible biomarker for assessing the perfusion status in the near peripheral retina, useful in RR-MS management. These findings could confirm the role of vascular dysfunction in the pathogenetic mechanisms of MS.

OCT-A in chronic central serous chorioretinopathy treated with oral eplerenone and half-fluence photodynamic therapy: A comparative study.

To evaluate retinal and choriocapillary vessel density (VD) changes in patients with chronic central serous chorioretinopathy (CSC) treated with half-fluence verteporfin photodynamic therapy (vPDT) or eplerenone, using optical coherence tomography angiography (OCTA). Patients affected by CSC and treated with vPDT and eplerenone were retrospectively studied. At baseline and 3 months after each treatment, all patients underwent a complete ophthalmological examination, including an evaluation of best-corrected visual acuity (BCVA), slit-lamp biomicroscopy, fundus examination, fluorescein angiography (FA), indocyanine green angiography (ICGA), spectral-domain optical coherence tomography (SD-OCT) and OCTA. Forty-eight eyes of patients with CSC were analysed. Twenty-four eyes were placed in the vPDT group, and 24 eyes formed the eplerenone group. In both groups, OCTA showed a significant improvement in the VD of deep capillary plexus (DCP) and choriocapillaris (CC) after treatments with respect to baseline (p < 0.001), whereas the VD of superficial capillary plexus (SCP) did not show significant differences (p > 0.05). The PDT group demonstrated a statistically significant increase in the VD of DCP and CC with respect to the eplerenone group (DCP p = 0.012; CC p = 0.004). A statistically significant reduction with respect to baseline in subfoveal choroidal thickness (SFCT) (p = 0.001 for vPDT group; p = 0.001 for eplerenone group) and in central foveal thickness (CFT) (p = 0.001 for vPDT group; p = 0.001 for eplerenone group) was also found. The SFCT was significantly thinnest in the PDT group with respect to the eplerenone group (p = 0.021). OCTA allowed us to study retinal and choriocapillary vascular changes in patients with CSC treated with vPDT and eplerenone.

Long-Term Retinal Vascular Changes in Age-Related Macular Degeneration Measured Using Optical Coherence Tomography Angiography.

To determine if age-related macular degeneration (AMD) status affects longitudinal retinal vessel changes. Retrospective, cohort study of 125 eyes (75 patients) with AMD, following retinal vessel density (VD) and foveal avascular zone (FAZ) measurements using optical coherence tomography angiography (OCT-A) over 24 months. FAZ area (<i>P</i> &lt; .001) and perimeter (<i>P</i> &lt; .001) increased over 2 years, with no difference between nonexudative and exudative AMD (<i>P</i> = .134-.976). Eyes with geographic atrophy (GA) showed greater progressive VD loss (<i>P</i> = .023-.038), and greater increase in FAZ area (<i>P</i> = .044) and perimeter (<i>P</i> = .040) compared to eyes without GA. Neither baseline nor 2-year change in vascular parameters were associated with choroidal neovascularization (CNV) or GA incidence in nonexudative AMD, or anti-VEGF injection frequency in exudative AMD (<i>P</i> = .070-.952). AMD eyes with GA undergo more rapid loss of retinal vessel density and FAZ enlargement over 2 years, suggesting a relationship between the retinal vasculature and AMD pathophysiology. <b>[<i>Ophthalmic Surg Lasers Imaging Retina</i> 2022;53:529-536.]</b>.