Association Between the Severity of Diabetic Retinopathy and Optical Coherence Tomography Angiography Metrics

Diabetic retinopathy, the most serious ocular complication of diabetes, imposes a serious economic burden on society. Automatic and objective assessment of vessel changes can effectively manage diabetic retinopathy and prevent blindness. Optical coherence tomography angiography (OCTA) metrics have been confirmed to be used to assess vessel changes. The accuracy and reliability of OCTA metrics are restricted by vessel segmentation methods. In this study, a multi-branch retinal vessel segmentation method is proposed, which is comparable to the segmentation results obtained from the manual segmentation, effectively extracting vessels in low contrast areas and improving the integrity of the extracted vessels. OCTA metrics based on the proposed segmentation method were validated to be reliable for further analysis of the relationship between OCTA metrics and diabetes and the severity of diabetic retinopathy. Changes in vessel morphology are influenced by systemic risk factors. However, there is a lack of analysis of the relationship between OCTA metrics and systemic risk factors. We conducted a cross-sectional study that included 362 eyes of 221 diabetic patients and 1,151 eyes of 587 healthy people. Eight systemic risk factors were confirmed to be closely related to diabetes. After controlling these systemic risk factors, significant OCTA metrics (such as vessel complexity index, vessel diameter index, and mean thickness of retinal nerve fiber layer centered in the macular) were found to be related to diabetic retinopathy and severe diabetic retinopathy. This study provides evidence to support the potential value of OCTA metrics as biomarkers of diabetic retinopathy.

The effect of systemic factors on retinal blood flow in patients with carotid stenosis: an optical coherence tomography angiography study

Carotid artery stenosis (CAS) is among the leading causes of mortality and permanent disabilities in the Western world. CAS is a consequence of systemic atherosclerotic disease affecting the majority of the aging population. Optical coherence tomography angiography (OCTA) is a novel imaging technique for visualizing retinal blood flow. It is a noninvasive, fast method for qualitative and quantitative assessment of the microcirculation. Cerebral and retinal circulation share similar anatomy, physiology, and embryology; thus, retinal microvasculature provides a unique opportunity to study the pathogenesis of cerebral small vessel disease in vivo. In this study, we aimed to analyze the effect of systemic risk factors on retinal blood flow in the eyes of patients with significant carotid artery stenosis using OCT angiography. A total of 112 eyes of 56 patients with significant carotid stenosis were included in the study. We found that several systemic factors, such as decreased estimated glomerular filtration rate (eGFR), hypertension, and carotid occlusion have a significant negative effect on retinal blood flow, while statin use and carotid surgery substantially improve ocular microcirculation. Neither diabetes, clopidogrel or acetylsalicylic acid use, BMI, serum lipid level, nor thrombocyte count showed a significant effect on ocular blood flow. Our results demonstrate that a systematic connection does exist between certain systemic risk factors and retinal blood flow in this patient population. OCTA could help in the assessment of cerebral circulation of patients with CAS due to its ability to detect subtle changes in retinal microcirculation that is considered to represent changes in intracranial blood flow.

Six-year incidence of age-related macular degeneration and correlation to OCT-derived drusen volume measurements in a Chinese population

AimsTo report the 6-year incidence of optical coherence tomography (OCT)-derived age-related changes in drusen volume and related systemic and ocular associations.MethodsChinese adults aged 40 years and older were assessed at baseline and 6 years with colour fundus photography (CFP) and spectral domain (SD) OCT. CFPs were graded for age-related macular degeneration (AMD) features and drusen volume was generated using commercially available automated software.ResultsA total of 4172 eyes of 2580 participants (mean age 58.12±9.03 years; 51.12% women) had baseline and 6-year follow-up CFP for grading, of these, 2130 eyes of 1305 participants had gradable SD-OCT images, available for analysis. Based on CFP grading, 136 (3.39%) participants developed incident early AMD and 10 (0.25%) late AMD. Concurrently, retinal pigment epithelial-Bruch’s membrane (RPE-BrC) volumes decreased, remained stable and increased in 6.8%, 78.5% and 14.7%, respectively, over 6 years. In eyes where RPE-BrC volumes were >0 mm3 at baseline, this was associated with two-fold higher prevalence rate of any AMD at baseline (p<0.001). Multivariable analysis showed that when compared with eyes where RPE-BrC volume was unchanged, volume decrease was significantly associated with older age (OR=1.30; p<0.001), smoking (OR=2.21; p=0.001) and chronic kidney disease (OR=3.4, p=0.008), while increase was associated with older age (OR=1.36; p<0.001) and hypertension (OR=1.43; p=0.016).ConclusionAMD incidence detected at 6 years on CFP and correlated OCT-derived drusen volume measurement change is low. Older age and some systemic risk factors are associated with drusen volume change, and our data provide new insights into relationship between systemic risk factors and outer retinal morphology in Asian eyes.

Non-arteritic anterior ischaemic optic neuropathy sequential to SARS-CoV-2 virus pneumonia: preventable by endothelial protection?

We present a case of non-arteritic anterior ischaemic optic neuropathy (NAION) with no ocular or systemic risk factors in a patient who recovered from a recent SARS-CoV-2 pneumonia. NAION is the most common acute optic neuropathy among individuals over 50 years of age. It results from a transient hypoperfusion of the optic nerve head circulation, especially in patients with low vascular compliance due to ocular or systemic risk factors. We attribute the ophthalmological condition to a SARS-CoV-2 virus-associated endotheliopathy that can be prevented with timely protection of endothelial function with vitamins D and K2.

Clinical characteristics of progressive nonarteritic anterior ischemic optic neuropathy

AIM: To study whether patients with progressive nonarteritic anterior ischemic optic neuropathy (NAION) present earlier than patients with stable NAION and to describe their clinical characteristics and visual outcome. METHODS: This was a retrospective chart review. All patients with NAION seen during the acute stage from January 2012 to December 2018 were reviewed. Patients were included if they had documented disc edema and follow up of at least 3mo. Patients with progressive NAION were identified if they worsened in 2 out of 3 parameters: visual acuity ≥3 Snellen lines; Color vision ≥4 Ishihara plates; the visual field defect involved a new quadrant. The clinical characteristics, time from symptom onset to presentation, systemic risk factors and visual outcome were compared to patients with stable NAION. RESULTS: Totally 122 NAION cases met the inclusion criteria. Mean age was 58.1y (range 22-74), 70% were men. Twenty cases (16.4%) had progressive NAION. Patients with progressive NAION did not differ from stable NAION in their demographics, systemic risk factors or in their initial visual deficit. At last follow up, median visual acuity was 1.0 logMAR (IQR 0.64-1.55) in patients with progressive NAION, vs 0.18 (IQR 0.1-0.63) in stable NAION (P&#x0026;#x003C;0.001). Median color vision testing was 0 plates correct (IQR 0-2.5%) vs 92% plates correct (IQR 50%-100%) in the stable NAION group (P&#x0026;#x003C;0.001). Patients with progressive NAION differed in the time from symptom onset to presentation (median 2d vs 5d, P=0.011). CONCLUSION: We find no identifiable risk factors associated with progressive NAION. Progressors arrive earlier for ophthalmological evaluation.

Multirezisztens kórokozók szűrése szürkehályog-műtét előtt

Összefoglaló. Bevezetés: A multirezisztens kórokozók által okozott fertőzések komoly gondot okoznak. Szemészeti szempontból az ebbe a körbe tartozó meticillinrezisztens Staphylococcus aureus (MRSA) baktérium bír kiemelkedő jelentőséggel. Célkitűzés: Multirezisztens kórokozók irányában cataractaműtét előtt álló betegektől mintavétel és adatelemzés. Módszer: 257, cataractaműtét előtt álló beteg esetében végeztünk multirezisztens kórokozók szűrésére vizsgálatot a conjunctivazsákból. A mikrobiológiai tenyésztés során multirezisztens kórokozóra pozitív eredményt adó betegek esetében a preoperatív kórtörténetet és az általános kísérő betegségeket feltártuk és elemeztük. Eredmények: A minták 17 beteg esetében multirezisztens kórokozóra pozitívak voltak. 11 esetben szisztémás rizikófaktorokat is találtunk. A pozitív betegeknél a műtétet csak a felszabadító mikrobiológiai eredmények birtokában végeztük el. A dekolonizált betegeknél ezt követően a szakmai protokoll normális antibiotikumprevencióját alkalmaztuk. A 257 beteg 6,6%-ában találtunk multirezisztenskórokozó- és 5%-ában MRSA-pozitivitást. Posztoperatív endophthalmitis nem fordult elő. Következtetés: A cataractaműtéteknél alkalmazott antibiotikus endophthalmitisprevenció multirezisztens kórokozóra pozitív betegeknél kevéssé hatékony lehet. Ezért javasolt a veszélyeztetett betegek multirezisztens kórokozókra történő szűrése és dekolonizációja. Orv Hetil. 2021; 162(3): 106–111. Summary. Introduction: Infections caused by multiresistant pathogens may have serious consequences. In ophthalmological practice, methicillin-resistant Staphylococcus aureus (MRSA) is the most important multiresistant pathogen. Objective: We took samples for multiresistant pathogens from patients assigned for cataract surgery. Method: We carried out multiresistant pathogen screening from conjunctival sac in 257 patients, who were assigned for cataract surgery. Preoperative case history and concomitant systemic diseases were evaluated in patients, who turned out to be positive for multiresistant pathogens during the screening procedure. Results: The samples were positive for multiresistant pathogens in 17 patients. In the case history of 11 multiresistant pathogen positive patients, previous systemic risk factors could be explored. Multiresistant pathogen positive patients were operated only after the decolonisation. After the decolonisation, the normal antibiotic prevention was used before the surgery. Multiresistant pathogen positive was 6.6%, MRSA positive was 5% of the 257 patients. There were no cases of endophthalmitis in any of these patients. Conclusion: Endophthalmitis prevention with antibiotics, according to the guidelines, may not be efficient in multiresistant pathogen positive patients. Therefore, it is advisable to screen multiresistant pathogens and decolonisation at risk patients before cataract surgery. Orv Hetil. 2021; 162(3): 106–111.