Carotid artery occlusive disease and ocular manifestations: Importance of identifying patients at risk

Quantitative Assessment of Retinal and Choroidal Microvasculature in Asymptomatic Patients with Carotid Artery Stenosis

SIGNIFICANCE

Carotid disease contributes to 15 to 20% of all ischemic strokes, one of the leading causes of permanent disabilities and mortality globally. With its growing prevalence and the inflicted disability rates, screening for anomalies that precede the onset of its serious complications is of crucial global significance.

PURPOSE

This study aimed to assess the relationship between retinal and choroidal perfusion changes with the degree of stenosis using quantitative swept-source optical coherence tomography angiography in patients with internal carotid artery stenosis.

METHODS

A retrospective cohort study was conducted in 72 eyes with carotid stenosis. According to the degree of stenosis, the participants were divided into a healthy group (group 1: 34 eyes), a mild-moderate stenosis group (group 2: 22 eyes), and a severe stenosis group (group 3: 16 eyes). Swept-source optical coherence tomography angiography was performed to scan macular fovea. Capillary density values in the different retinal and choroidal layers were the major measurements for our study.

RESULTS

Mean vessel density in the midchoroid layer was significantly higher in groups 2 and 3 compared with group 1. Deep choroid disclosed significantly superior vascular density values in group 3 compared with groups 2 and 1. Superficial and deep capillary plexus showed decreased vascular density values when comparing group 3 with groups 1 and 2, although they were not significant.

CONCLUSIONS

Our report provides the first evidence that choroidal microvascular changes were correlated with severity of carotid artery stenosis. Optical coherence tomography angiography can sensitively detect subtle, early changes in the ocular blood in carotid disease representing a useful, noninvasive, and objective approach to the retinal microvasculature.

Retinal Thickness Correlates with Cerebral Hemodynamic Changes in Patients with Carotid Artery Stenosis

Background: We aimed to assess the retinal structural and choroidal changes in carotid artery stenosis (CAS) patients and their association with cerebral hemodynamic changes. Asymptomatic and symptomatic patients with unilateral CAS were enrolled in our study. Material and methods: Swept-source optical coherence tomography (SS-OCT) was used to image the retinal nerve fiber layer (RNFL), ganglion cell-inner plexiform layer (GCIPL), while SS-OCT angiography (SS-OCTA) was used to image and measure the choroidal vascular volume (CVV) and choroidal vascular index (CVI). Computed Tomography Perfusion (CTP) was used to assess the cerebral perfusion parameters; relative perfusion (r) was calculated as the ratio of the value on the contralateral side to that on the ipsilateral side. Results: Compared with contralateral eyes, ipsilateral eyes showed significantly thinner RNFL (p < 0.001), GCIPL (p = 0.013) and CVV (p = 0.001). Relative cerebral blood volume (rCBV) showed a significant correlation with RNFL (p < 0.001), GCIPL (p < 0.001) and CVI (p = 0.027), while the relative permeability surface (rPS) correlated with RNFL (p < 0.001) and GCIPL (p < 0.001). Conclusions: Our report suggests that retinal and choroidal changes have the potential to detect hemodynamic changes in CAS patients and could predict the risk of stroke.

Association Between Retinal Microvascular Metrics Using Optical Coherence Tomography Angiography and Carotid Artery Stenosis in a Chinese Cohort

Objectives: The main aim was to investigate the association between retinal microvascular metrics using optical coherence tomography angiography (OCTA) and carotid artery stenosis (CAS) in an aging Chinese cohort.

Methods: In this cross-sectional and observational study, 138 eyes of 138 participants were examined. Indices of the microcirculation measured by OCTA included mean vessel density (VD), skeleton density (SD), vessel diameter index (VDI), fractal dimension (FD) and foveal avascular zone (FAZ) of the superficial retinal layer (SRL) and deep retinal layer (DRL), and peripapillary vessel caliber. The correlation of these indices with the carotid atherosclerotic lesions including carotid intima media thickness (CIMT) and common carotid artery (CCA) plaque was assessed.

Results: A total of 72 of 138 eyes demonstrated an increased (≥1 mm) CIMT, and 32 of the eyes presented common carotid plaques. Macular VD, SD, and FD were decreased with the increasing CCA caliber diameter (p &lt; 0.05, respectively). Superficial and deep macular FDs were negatively associated with CIMT as well as the existence of CCA plaques (p &lt; 0.05, respectively).

Conclusion: Changes in retinal microvasculature accessed by OCTA may be used as one of the non-invasive early indicators to monitor asymptomatic CAS.

Choroidal changes in carotid stenosis patients after stenting detected by swept-source optical coherence tomography angiography

BACKGROUND

Carotid artery stenosis (CAS) patients show reduced blood flow in the ophthalmic artery. This study aimed to assess the changes in the choriocapillaris and choroidal thickness in patients with unilateral carotid artery stenosis after carotid stenting using swept-source optical coherence tomography (SS-OCT)/swept-source optical coherence tomography angiography (SS-OCTA).

METHODS

Fifty-three mild to moderate CAS patients and 40 controls were enrolled in this study. All participants underwent digital subtraction angiography (DSA) and SS-OCT/SS-OCTAA imaging before and 4 days after carotid artery stenting. SS-OCTA was used to image and measure the perfusion of the choriocapillaris (mm2) while SS-OCT was used to image and measure the choroidal thickness (µm). The stenosed side was described as the ipsilateral eye while the other side was the contralateral eye.

RESULTS

Choroidal thickness was significantly thinner (P = 0.024) in CAS when compared with controls. Ipsilateral eyes of CAS patients showed significantly thinner (P = 0.008) choroidal thickness when compared with contralateral eyes. Ipsilateral eyes of CAS patients showed thicker (P = 0.027) choroidal thickness after carotid artery stenting while contralateral eyes showed thinner choroidal thickness (P = 0.039).

CONCLUSIONS

Our report suggests that in vivo quantification of the choroid with the SS-OCT/SS-OCTA may allow monitoring of CAS and enable the assessment of purported treatments.

Quantitative Optical Coherence Tomography Angiography Detects Retinal Perfusion Changes in Carotid Artery Stenosis

Background

Carotid artery stenosis (CAS) is a multifaceted disease characterized by possible ocular involvement. Treatment with carotid endarterectomy helps to restore cerebral perfusion, which may prevent ocular and cerebral complications. The main aim was to assess retinal and choroidal vascular perfusion changes before and after endarterectomy in patients affected by CAS.

Methods

The design of the study was prospective and observational, including patients affected by CAS and healthy controls. The follow-up was 3 months. We performed quantitative optical coherence tomography (OCT) angiography (OCTA) analyses of retinal perfusion changes, before and after endarterectomy. The main outcome measures were the quantitative changes of choroidal thickness (CT), retinal nerve fiber layer (RNFL), and ganglion cell layer (GCL); vessel density (VD); and vessel tortuosity (VT) OCTA metrics were also measured.

Results

Sixty eyes of 30 patients affected by CAS and 30 eyes of 30 controls were included. We separately considered the ipsilateral eyes to CAS, the contralateral eyes to CAS, and the healthy eyes. Visual symptoms were absent in all the patients. RNFL and GCL resulted similar between patients and controls (p > 0.05). CT was significantly thinner in ipsilateral eyes than controls (p < 0.01), and it resulted unchanged after surgery (p > 0.05). VD resulted significantly altered only in some plexa of the ipsilateral eyes (p < 0.01), whereas VT disclosed decreased values of the entire retinal vascular network, both in ipsilateral and contralateral eyes (p < 0.05). Endarterectomy was followed by statistically significant improvement of retinal perfusion (p < 0.05).

Conclusion

Optical coherence tomography angiography can noninvasively detect postendarterectomy retinal perfusion improvements in CAS patients with baseline diabetes and hypertension as a systemic risk factor.

Significant changes of the choroid in patients with ocular ischemic syndrome and symptomatic carotid artery stenosis

Purpose

To evaluated the changes in choroidal vasculature in patients with ocular ischemic syndrome (OIS) and in the ipsilateral eyes of patients with symptomatic carotid artery stenosis (CAS)

Method

A total of 50 patients (15 patients with OIS, 10 patients with symptomatic CAS, 25 patients of age-and sex-matched control group) were included, and the medical records were retrospectively reviewed. The mean subfoveal choroidal thickness (SFCT) of each eye was measured, and binary images of the choroid were evaluated to compare the mean choroidal area and the luminal area.

Results

The mean SFCT was 170.5±75.3 μm in the eyes with OIS, 154.8±62.9 μm in the ipsilateral eyes with symptomatic CAS, and 277.5±73.2 μm in the right eyes of the control group patients (P<0.001). The mean choroidal area was 494,478.6±181,846.2 μm2 in the eyes with OIS, 453,750.0±196,725.8 μm2 in the ipsilateral eyes with symptomatic CAS, and 720,520±281,319.5 μm2 in the control group eyes (P = 0.036). The mean luminal area was 333,185.7±112,665.9 μm2 in the eyes with OIS, 313,983.3±132,032.1 μm2 in the ipsilateral eyes with symptomatic CAS, and 480,325.0±185,112.6 μm2 in the control group eyes (P = 0.046). The mean SFCT, mean choroidal area, and mean luminal area were significantly smaller in the eyes with OIS (P = 0.017, P = 0.005, and P = 0.004, respectively), and those with symptomatic CAS (P = 0.020, P = 0.016, and P = 0.021, respectively) than in the unaffected contralateral eyes. There were no significant differences between the eyes in the control group (P = 0.984, P = 284, and P = 0.413, respectively).

Conclusion

The mean SFCT, mean choroidal area, and mean luminal area were significantly thinner in the eyes with OIS and the ipsilateral eyes with symptomatic CAS, compared with the control group eyes. The eyes with OIS and those with symptomatic CAS had significantly thinner SFCT, and smaller choroidal area and luminal area than the unaffected contralateral eyes. Choroid may reflect the vascular status of the carotid artery, indicated by choroidal thinning and decreasing choroidal area, especially luminal area.

Carotid Artery Endarterectomy Effect on Choroidal Thickness: One-Year Follow-Up

Purpose

To evaluate the change in choroidal thickness after carotid artery endarterectomy (CEA) in patients without retinal pathology.

Methods

A prospective series of patients who underwent CEA at the Tel Aviv Medical Center. Spectral domain optical coherence tomography (SD-OCT) was performed one day before the CEA and at least 6 months after. Data included medical history, smoking history, percentage of carotid stenosis before and after CEA, best-corrected visual acuity (BCVA), central macular thickness (CMT), and choroidal thickness (subfoveal, 500 µm, 1000 µm, and 1500 µm nasal and temporal).

Results

Eight patients (seven male and one female) with a mean age of 70.5 ± 6.1 years were included in the study. The mean internal carotid artery (ICA) stenosis was 89.8% ± 5.1 in the operated side, 33.7% ± 10.9 in the nonoperated side (p < 0.0001), and 0% after CEA (p < 0.0001). Operated side BCVA was 0.35 ± 0.66 compared to 0.61 ± 0.83 in the nonoperated side (p=0.51). The mean subfoveal choroidal thickness (SFChT) of the operated side was 277 ± 67 µm compared to 268 ± 71 µm in the nonoperated side (p=0.81). SFChT and CMT after CEA were 275 ± 64 µm (p=0.96) and 268 ± 29 µm (p=0.98), respectively.

Conclusions

SFChT and CMT in patients without retinal or choroidal pathology and significant ICA stenosis can be normal and may not change after successful ipsilateral CEA.

Venous Thromboembolism and Cerebrovascular Events in Patients with Giant Cell Arteritis: A Population-Based Retrospective Cohort Study

Objective

To investigate the incidence of venous thromboembolism (VTE) and cerebrovascular events in a community-based incidence cohort of patients with giant cell arteritis (GCA) compared to the general population.

Methods

A population-based inception cohort of patients with incident GCA between January 1, 1950 and December 31, 2009 in Olmsted County, Minnesota and a cohort of non-GCA subjects from the same population were assembled and followed until December 31, 2013. Confirmed VTE and cerebrovascular events were identified through direct medical record review.

Results

The study population included 244 patients with GCA with a mean ± SD age at diagnosis of 76.2 ± 8.2 years (79% women) and an average length of follow-up of 10.2 ± 6.8 years. Compared to non-GCA subjects of similar age and sex, patients diagnosed with GCA had a higher incidence (%) of amaurosis fugax (cumulative incidence ± SE: 2.1 ± 0.9 versus 0, respectively; p = 0.014) but similar rates of stroke, transient ischemic attack (TIA), and VTE. Among patients with GCA, neither baseline characteristics nor laboratory parameters at diagnosis reliably predicted risk of VTE or cerebrovascular events.

Conclusion

In this population-based study, the incidence of VTE, stroke and TIA was similar in patients with GCA compared to non-GCA subjects.

The role of lipid dysregulation and vascular risk factors in glaucomatous retrobulbar circulation

The aim of this study was to evaluate selected lipid-related and vascular factors and their effect on retrobulbar hemodynamics in glaucoma. Fifty-six patients with primary open angle glaucoma (POAG) [POAG group; mean age 68.32 years (SD±0.21)] and 54 patients in control group [CG, mean age 68.1 years (SD±5.34)] were examined. Peak systolic velocity, end-diastolic velocity, mean velocity, pulsatility index, and resistive index of the ophthalmic artery, the central retinal artery and the posterior ciliary arteries were measured by Color Doppler Imaging. Selected lipid-related, systemic and local vascular parameters were evaluated. Statistical methods included Shapiro-Wilk, Student-t and Mann-Whitney U tests, and Spearman rank correlations. In POAG group systolic arterial blood pressure, diastolic arterial blood pressure, total cholesterol, low density lipoprotein cholesterol (LDL-ch), and intraocular pressure were significantly higher; while ocular perfusion pressure, high density lipoprotein cholesterol (HDL-ch) and diastolic ocular perfusion pressure were significantly lower (p≤0.05). Color Doppler Imaging confirmed blood flow abnormalities in all investigated arteries. In addition, significant correlations of HDL-ch, LDL-ch and triglycerides (TG) with peak systolic velocity, end-diastolic velocity and mean velocity were found in individual arteries (p≤0.05). Also, significant associations of systolic arterial blood pressure, ocular perfusion pressure, systolic oclular perfusion pressure and diastolic ocular perfusion pressure with peak systolic velocity, end-diastolic velocity, mean velocity and resistive index were revealed in the posterior ciliary arteries (p≤0.05). Dysregulation of lipid-related and vascular factors, as well as statistical correlation between the above and retrobulbar blood flow indices, might imply their role in vasoconstrictive processes during glaucomatous endotheliopathy.

Bilateral Ocular Ischaemic Syndrome-Rare Complication of Rhinocerebral Mucormycosis in an Omani Patient: Case report and literature review

Ocular ischaemic syndrome (OIS) is a relatively uncommon condition. Simultaneous bilateral involvement is even less common and has been reported in only 22% of all cases of OIS. It has variable clinical presentations, of which visual loss and ocular pain are the most common. It is believed to occur when there is a 90% or greater carotid artery obstruction. This syndrome is often associated with a number of systemic diseases including diabetes mellitus, hypertension, coronary artery disease, and cerebrovascular disease. Only occasionally has it been described as a complication of rhinocerebral mucormycosis. We report an unusual case of bilateral OIS secondary to bilateral internal carotid artery thrombosis as a complication of invasive rhinocerebral mucormycosis. In addition, a review of clinical presentation, diagnostic work-up and treatment options for OIS is provided.

Ophthalmic features of systemic diseases

The eye is intricately integrated with the functions of the body. Ocular changes may precede or run concurrently with various systemic conditions and often represent important prognostic indicators of disease progression. In addition to a thorough diagnostic evaluation and treatment of underlying processes, individuals with systemic diseases and concurrent ocular changes may need comprehensive ophthalmic examination to reduce the risk of visual impairment and morbidity. In this review the authors highlight the clinically relevant ocular signs that occur parallel with systemic conditions. In particular, the study focuses on the varied clinical presentations that can lead to rapid diagnosis to improve management of eye disorders that accompany systemic diseases.