The alterations of retinal vasculature detected on optical coherence tomography angiography associated with chronic obstructive pulmonary disease

Evaluation of retinal structural and microvascular changes in patients with acute pancreatitis

BACKGROUND

This study aimed to show the changes in retinal vascular densities and thicknesses in the peripapillary and macular regions in the acute period in patients with acute pancreatitis (AP).

METHODS

This prospective cross-sectional study included 57 eyes of 30 patients with AP and 58 eyes of 30 healthy people. Optical coherence tomography angiography (OCTA) was taken within 24-72 h of AP patients' hospitalization. OCTA was used to evaluate the retinal microvascular structure and retinal thickness.

RESULTS

Peripapillary retinal nerve fiber layer (pp-RNFL) and perifoveolar ganglion cell complex (pef-GCC) thickness in patients with AP were significantly higher than in the healthy control group (p = 0.020 and p = 0.039, respectively). While whole image vessel density (wiVD) and perifoveal vessel density (pefVD) were significantly lower in the deep capillary plexus (DCP), choriocapillaris flow area (CCFA) in the macula were significantly lower in each of the 1 mm and 3 mm radius areas in patients with AP (p = 0.014, p = 0.011; p = 0.011, and p = 0.035 respectively). In the univariable and multivariable linear regression analysis, it was observed that serum lipase and procalcitonin levels affected the thickness of pp-RNFL and pef-GCC (for pp-RNFL, β= 0.001, p = 0.002, β=24.992, p < 0.001, and for pef-GCC, β= 0.001 p = 0.014, β=17.107 p < 0.001 respectively).

CONCLUSIONS

There are significant microvascular and structural changes in the optic nerve and macula in patients with AP. The relationship between these changes and serum lipase and procalcitonin levels was shown. Clinicians should consider ocular involvement in AP patients with high serum lipase and procalcitonin levels.

Evaluation of Retinal and Posterior Segment Vascular Changes Due to Systemic Hypoxia Using Optical Coherence Tomography Angiography

Background/Objectives: Retinal vascular occlusions are a significant cause of visual impairment in older adults, resulting in ischemic retinal damage and sudden vision loss. This study evaluates the retinal, optic nerve head (ONH), and choroidal capillary networks in chronic and acute-on-chronic hypoxia compared to normal controls using optical coherence tomography angiography (OCT-A). Methods: We evaluated a prospective study including twenty patients in the hypoxic group (mean age 61.2 ± 10.2) in two phases, chronic hypoxia and acute-on-chronic hypoxia, and 21 control subjects (mean age 59 ± 9.4 years). All patients underwent a comprehensive eye examination, OCT, and OCT-A imaging. The data were analyzed using OCT-A analysis software (Zeiss OCT-A software 2.1.0.55513) and Fiji software (1.51a). Vascular density of the retina and ONH, choriocapillaries, and foveal avascular zone (FAZ) size were measured. Results: The superficial peripapillary vascular density was higher for the control group (0.387 ± 0.03) compared to the hypoxic patients with (0.383 ± 0.03) and without O2 supplementation (0.383 ± 0.03; p = 0.018). No retinal angiographic differences were identified between the two study groups. The ganglion cell layer (GCL) was thinner in the hypoxic group. Both hypoxic subgroups demonstrated denser choriocapillaries (mean 13,073 ± 1812 and 12,689 ± 1815, with and without O2 supplementation, respectively) compared to the control group (mean 9749 ± 2881, p < 0.001 for both groups). Hypoxic patients demonstrated increased area size of choriocapillaries (+O2 supplementation-mean 44,347 ± 10,563; -O2 supplementation-mean 46,984 ± 12,822) compared to the control group (mean 30,979 ± 9635; p < 0.01 and p < 0.001, respectively). Conclusions: Chronic and acute-on-chronic hypoxia did not affect the retinal vascular network, most probably due to the strong autoregulation of vascular function of the retina. However, compared to the control group, GCL, ONH vasculature density, and most choriocapillaries indices were significantly altered among hypoxic patients.

Investigation of ocular microstructural changes according to disease severity in patients with chronic obstructive pulmonary disease

OBJECTIVE

To investigate retinal nerve fibre layer (RNFL) thickness and vascular density alterations in the retina and optic disc in patients with chronic obstructive pulmonary disease (COPD).

METHODS

A total of 66 COPD patients and 54 age- and sex-matched healthy individuals were enrolled in this prospective cross-sectional study. The COPD patients were divided into 3 subgroups (mild, moderate, and severe COPD) based on spirometric parameters as per the Global Initiative for Chronic Obstructive Lung Disease guideline. RNFL thickness, foveal avascular zone area, and vessel density in the superficial capillary plexus, deep capillary plexus, and radial peripapillary capillary plexus were measured by optical coherence angiography and compared among groups.

RESULTS

There was no significant difference between COPD patients and control individuals in terms of foveal avascular zone area or RNFL thickness (p = 0.891 and p = 0.896, respectively). Patients with severe COPD showed lower vessel density in the superficial capillary plexus compared with the other groups, but the difference was not significant (p > 0.05). In the deep capillary plexus, vessel density did not differ significantly among groups in the foveal region (p > 0.05) but was significantly lower in all parafoveal quadrants in the severe COPD group. Radial peripapillary capillary plexus vessel density also was lower in the severe COPD group, especially the peripapillary region (p = 0.044).

CONCLUSION

Although COPD is primarily a lung disease, the eye seems to be among the tissues affected in its natural course. The effects are more pronounced in patients with severe COPD and in the deep capillary plexus and radial peripapillary capillary plexus.

Retinal microvascular changes in patients recovered from COVID-19 compared to healthy controls: A meta-analysis

PURPOSE

To investigate changes in retinal microcirculation in patients recovered from COVID-19 infection compared to healthy controls, using optical coherence tomography-angiography.

METHODS

Meta-analysis of eligible studies comparing retinal microcirculation between patients recovered from COVID-19 infection and healthy controls up to 7th of September 2022 was performed, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 guidelines. The following search algorithm was used: (COVID-19 OR coronavirus) AND (retina OR optical coherence tomography OR optical coherence tomography angiography OR vessel density OR foveal avascular zone). Standardized Mean Difference (SMD) with 95% confidence interval (CI) was calculated to compare continuous variables. Revman 5.3 was used for the analysis.

RESULTS

12 studies were included in our analysis. Foveal avascular zone (FAZ) area was larger in patients recovered from COVID-19 infection compared to healthy controls, while there was no statistically significant difference in FAZ perimeter between the two groups. The foveal, parafoveal and whole image vessel density in the superficial capillary plexus showed no significant difference between the two groups. The foveal, parafoveal and whole image vessel density in the deep capillary plexus was statistically lower in patients recovered from COVID-19 compared to healthy controls.

CONCLUSION

FAZ area was enlarged and foveal, parafoveal and whole image vessel density in deep capillary plexus were reduced in patients recovered from COVID-19 infection compared to healthy controls, suggesting that COVID-19 infection may induce long-term retinal microvascular changes in patients recovered from the virus infection.

Evaluation of Ocular Microvascular Characteristics in Smokers and Patients with Chronic Obstructive Pulmonary Disease Using an Optical Coherence Tomography Angiography

PURPOSE

To investigate retinal microvascular changes in patients with chronic obstructive pulmonary disease (COPD) using optical coherence tomography angiography (OCTA) and to compare these values with those of smokers and healthy non-smokers.

METHODS

This study was performed on 38 eyes of 38 patients with COPD, 30 eyes of 30 smokers, and 31 eyes of 31 healthy non-smokers. Foveal avascular zone (FAZ) area, superficial (SCP) and deep (DCP) capillary plexus (whole image, fovea, parafovea, and perifovea) and radial peripapillary capillary (RPC) vessel densities (whole image, peripapillary, and inside disc) were evaluated via OCTA device (Optovue, Fremont, CA, USA). The forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) ratio and FEV1 values of patients with COPD were recorded.

RESULTS

There were statistically similar values in smoking pack-years between the smoker and COPD groups (p = 0.059). Entire SCP and DCP vessel densities were significantly different among the all groups (p < 0.05); for these parameters, the control group had the highest and the COPD group had the lowest vessel density values. Significantly decreased RPC vessel densities in all regions were detected in the COPD group compared with the other groups. Multiple regression analysis showed significant positive correlations between the FEV1 and the SCP, DCP, and RPC vessel densities (for all, p < 0.05).

CONCLUSIONS

This study detected lower vessel densities in patients with COPD than in smokers and healthy controls and reported decreased vessel density measurements with increasing COPD severity. COPD patients with or without a history of smoking may benefit from higher prioritization in terms of ophthalmic screening to prevent ocular complications.

Optical coherence tomography angiography as a surrogate marker for end-organ resuscitation in sepsis: A review

Sepsis is a severe illness which results in alterations in the end organ microvascular haemodynamics and is associated with a high risk of mortality. There is currently no real-time method of monitoring microcirculatory perfusion during sepsis. Retinal microcirculation is closely linked to cerebral perfusion and may reflect systemic vascular alterations. Retinal perfusion can be assessed using the non-invasive imaging technique of optical coherence tomography angiography (OCTA). This narrative review aims to discuss the utility of using retinal imaging and OCTA in systemic illness and sepsis. OCTA can be used as a functional, non-invasive and real-time biomarker along with other haemodynamic parameters for assessing and managing patients with sepsis.