|Year : 2015 | Volume
| Issue : 1 | Page : 181-183
Risk evaluation for cerebrovascular accident in cases of retinal vein occlusion
Faried M Wagdy1, Ahmed A El-Adly2, Osama A El-Morsy1, Hassan G Farahat1
1 Department of Ophthalmology, Faculty of Medicine, Menoufia University, Menoufia, Egypt
2 Nasser Institute for Research and Treatment, Cairo, Egypt
|Date of Submission||17-Nov-2013|
|Date of Acceptance||13-Mar-2014|
|Date of Web Publication||29-Apr-2015|
Faried M Wagdy
Shebin El Kom
Source of Support: None, Conflict of Interest: None
The aim of this study was to evaluate the risk factors that may predict the development of cerebrovascular accidents (CVAs) in patients with retinal vein occlusion (RVO).
Risk factors for RVO include hypertension, hyperlipidaemia, diabetes mellitus and vascular diseases, which are the same risk factors for CVAs.
Materials and Methods
Twenty patients with RVO (group A) and 20 normal controls with no history of RVO (group B) were examined and investigated using colour fundus photography and fluorescein angiography, carotid duplex ultrasonography and blood examinations for bleeding disorders, diabetes mellitus and hyperlipidaemia. The risk for CVAs was evaluated in both groups during a follow-up period of 12 months.
Four patients (20%) in group A suffered from some degree of CVA throughout the follow-up period, ranging from transient ischaemic attacks in three patients to cerebrovascular stroke in one patient. In contrast, none of the other control group individuals suffered any type of CVA during the follow-up period. Sixteen patients (80%) in the cases group had some degree of stenosis of their ipsilateral internal carotid artery (ICA), compared with only 12 individuals (60%) in the control group. The mean percentage degree of stenosis of the ipsilateral ICA detected by carotid ultrasonography in group A was 15.25%, whereas the mean percentage degree of stenosis in group B was 8%.
The number of individuals who had CVAs and some degree of stenosis of their ipsilateral ICA was higher in patients with RVO than in the control group, and the mean percentage degree of carotid stenosis was higher in group A than in group B.
Keywords: Carotid artery atherosclerosis, cerebrovascular accident, retinal vein occlusion, stenosis of the internal carotid artery
|How to cite this article:|
Wagdy FM, El-Adly AA, El-Morsy OA, Farahat HG. Risk evaluation for cerebrovascular accident in cases of retinal vein occlusion. Menoufia Med J 2015;28:181-3
|How to cite this URL:|
Wagdy FM, El-Adly AA, El-Morsy OA, Farahat HG. Risk evaluation for cerebrovascular accident in cases of retinal vein occlusion. Menoufia Med J [serial online] 2015 [cited 2019 Sep 21];28:181-3. Available from: http://www.mmj.eg.net/text.asp?2015/28/1/181/155985
| Introduction|| |
Retinal vein occlusion (RVO) is the second most common form of retinal vascular disease causing vision loss. Central retinal vein occlusion (CRVO) typically arises when the central retinal vein is occluded posterior to or within the lamina cribrosa . Thrombus formation is the most common cause, with systemic hypertension, cardiovascular disease, diabetes mellitus and open angle glaucoma as predisposing factors .
RVOs are classified according to whether the central retinal vein or one of its branches is obstructed. Although classified together, CRVO and branch retinal vein occlusion (BRVO) differ with respect to their pathophysiology, underlying systemic associations, average age of onset, clinical course and therapy. Both CRVO and BRVO can be divided further into ischaemic and nonischaemic varieties .
Risk factors identified for RVO include hypertension, vascular disease and diabetes mellitus. Several of these factors are in turn risk factors for cerebrovascular accidents (CVAs) .
A stroke, or CVA, is the rapid loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischaemia (lack of blood flow) caused by blockage (thrombosis, arterial embolism), or a haemorrhage . As a result, the affected area of the brain cannot function, which might result in an inability to move one or more limbs on one side of the body, inability to understand or formulate speech, or an inability to see one side of the visual field .
The diagnosis of the stroke itself is clinical, with assistance from the imaging techniques: computed tomographic scans or MRI. Doppler ultrasound and arteriography also assist in determining the subtypes and cause of stroke .
| Materials and methods|| |
This prospective study included two groups: a group of patients with RVO (group A) and the control group (group B). Ophthalmic history was taken from them regarding the onset, course and duration of diminution of vision, history of drug intake for eye diseases and history of previous eye surgery. Medical history was also taken with respect to diabetes mellitus, hypertension, cardiac diseases and other relevant medical conditions. The examination included uncorrected visual acuity, refraction, best-corrected visual acuity, colour vision testing, pupillary light reflex testing, slit-lamp examination of the anterior segment, intraocular pressure measurement using a Goldmann applanation tonometer and posterior segment examination with biomicroscopy, investigation using colour photography of both fundi to distinguish the asymmetry of the clinical picture and define the type of occlusion - whether CRVO or BRVO - and fundus fluorescein angiography of both fundi to detect whether the occlusion was of ischaemic or nonischaemic type. Cases with other causes of retinal ischaemia were excluded from our study.
CVA detection was carried out through carotid system ultrasound study, which is a diagnostic technique for evaluation of carotid artery occlusive disease to detect plaques, stenosis and degree of stenosis or occlusion of internal carotid arteries (ICAs), as well as through analysis of the coagulation profile to detect the presence of thrombophilia and analysis of the lipid profile to detect hyperlipidaemia.
Both groups were compared as regards these criteria and the statistical results were analysed and compared using the t-test and P values.
| Results|| |
As regards sex, age, hypertension, diabetes mellitus, bleeding disorders and hyperlipidaemia there was no significant statistical difference between cases and controls. The mean percentage degree of stenosis of the ipsilateral ICA detected by carotid ultrasonography was higher in group A than in group B with a P value of 0.046, and as regards occurrence of CVAs in both groups there was significant statistical difference with a P value of 0.035 with a greater incidence of CVAs in group A than in group B. No significant statistical difference was found between the ischaemic and nonischaemic groups as regards the degree of stenosis of ipsilateral ICA and the incidence of CVAs as the P value in the degree of stenosis was 0.208 and in CVAs was 0.639.
| Discussion|| |
In the present study, 20 patients with RVO had a higher incidence of CVAs compared with 20 age-matched and sex-matched controls (P = 0.035). The mean percentage degree of stenosis of the ipsilateral ICA detected by carotid duplex ultrasonography was higher in cases than in controls (P = 0.046). There was no significant statistical difference between the ischaemic and nonischaemic groups as regards the mean percentage degree of stenosis of the ipsilateral ICA and the incidence of CVAs as the P value for the degree of stenosis was 0.208 and that for CVAs was 0.639.
The results above were in agreement with those of a study by Holekamp who used a retrospective design for the assessment of risk of CVAs in cases of RVO. That study included 4500 patients with RVO and 13 500 controls. Of the patients with RVO, 62.9% had BRVO and 37.1% had CRVO. The rate of CVA events in the RVO cohort was almost double that of the control cohort (adjusted relative risk, 1.72; 95% confidence interval, 1.27-2.34; P = 0.001) .
Moreover, the present study was in agreement with another study carried out in 2012 by Bertelsen and colleagues named 'Comorbidity in patients with branch retinal vein occlusion', which was a case-control study with prospective follow-up data from Danish national registries. The study included 1168 patients with photographically verified BRVO and 116 800 controls. After the diagnosis, patients were seen to have an increased risk for cerebrovascular disease (1.27-1.76) .
Another study that agreed with ours was the one by Hayreh carried out at the Departments of Ophthalmology and Visual Sciences, College of Medicine, University of Iowa, Iowa City, Iowa, USA. In that study a search was conducted for systemic diseases associated with various types of RVO including BRVO, and it showed a greater prevalence of cerebrovascular disease (P = 0.007) .
In contrast to our results, another study by Tien Yin Wong et al., using pooled data analysis of two population-based cohorts to assess the association of RVO with cerebrovascular mortality, showed that, of 8384 baseline participants, 96 (1.14%) had RVO at baseline. Over 12 years, 341 (4.1%) died of cerebrovascular-related conditions with conclusion. After adjusting for age, sex, BMI, hypertension, diabetes, smoking, glaucoma and study site, RVO was not associated with cerebrovascular-related mortality .
Another study done by Peternel  to detect the changes of carotid arteries in cases of CRVO as assessed by Doppler ultrasound on 23 patients of CRVO showed that eight of them had haemodynamically significant stenosis of the ipsilateral carotid artery, whereas no one of 16 CRVO or 16 control groups showed any changes in carotid artery.
These results clearly demonstrate that risk for CVAs increases in patients with RVO.
The examination of carotid arteries in our study was performed after and not before or at the time of RVO. Therefore, this study did not provide definite evidence on the causal relationship between carotid artery disease and CRVO. However, if not a direct embolic consequence of proximal atherosclerotic lesions, CRVO is at least a marker of widespread atherosclerotic disease in the carotid tree.
The information derived from this study may become important when assessing the systemic safety profiles of new interventions for RVO. It may be useful for retinal specialists to know the baseline incidence of CVA, and other comorbidities in this patient population when collecting safety information on new treatments for RVO that may have systemic biologic activity [Table 1],[Table 2],[Table 3],[Table 4] and [Table 5].
|Table 2: Difference in the number of persons affected among cases and controls as regards stenosis of the ipsilateral|
internal carotid artery and cerebrovascular accidents
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|Table 3: Mean value of the percentage degree of stenosis of ipsilateral internal carotid artery in cases and the control group|
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|Table 4: Difference in the number of persons affected in ischaemic and nonischaemic groups as regards stenosis of|
ipsilateral internal carotid artery and cerebrovascular accidents
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|Table 5: Mean percentage degree of stenosis of ipsilateral internal carotid artery in ischaemic and nonischaemic retinal vein occlusion groups|
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| Conclusion|| |
Risk for CVAs was significantly higher in patients affected by RVO than in the normal population of the same age and sex because of the significant increase in the degree of stenosis of the ipsilateral ICAs in RVO-affected patients.
| Acknowledgements|| |
Conflicts of interest
There are no conflicts of interest.
| References|| |
Mahoney PRA, David T. Arch Ophthalmol 2008; 126
Langston D. Retina and vitreous. Manual of ocular diagnosis and therapy. Volume 8. Lippincott Williams & Wilkins 2002.
Holekamp N. Risk evaluation for myocardial infarction and cerebrovascular accident in retinal vein occlusion. Retin Today J 2011; 71
Sims NR, Muyderman H. Mitochondria, oxidative metabolism and cell death in stroke. Biochim Biophys Acta 2009; 1802
Donnan GA, Fisher M, Macleod M, Davis SM. Stroke. Lancet 2008; 371
Bertelsen M, et al.
Comorbidity in patients with branch retinal vein occlusion: case-control study. BMJ 2012; 345
Hayreh SS. Systemic diseases associated with various types of retinal vein occlusion. Am J Ophthalmol 2001: 131
Cugati S. Retinal vein occlusion and vascular mortality. Ophthalmology 2007; 520-526.
Peternel P. Carotid arteries in central retinal vessel occlusion as assessed by Doppler ultrasound. Br J Ophthalmol 1989 73
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]