Combined central retinal arterial and venous obstruction: emergency ophthalmic arterial fibrinolysis

Clinical Features of Central Retinal Vein Occlusion in Young Patients

Retinal vein occlusion (RVO) is the second most common retinal vascular disease. Central RVO (CRVO), in which obstruction occurs posterior to the lamina cribrosa due to various causes, manifests with extensive venous tortuosity, dilatation of blood vessels in the four quadrants, and retinal hemorrhage. The presence of macular edema decreases visual acuity in patients with CRVO, especially in elderly patients with hypertension, hyperlipidemia, and diabetes. In the last decade, treatment modalities for CRVO have improved, with anti-vascular endothelial growth factor agents being widely used as treatment. However, there are cases of refractory or recurrent macular edema. Moreover, CRVO also occurs in young patients. This article reviews previous studies and case reports and summarizes the differences in etiological factors, clinical manifestations, treatment, and prognosis between young and elderly patients. Due to the low incidence of CRVO in young patients, clinical data from these age groups are limited. Hence, further studies are warranted to explore the differences between age groups to improve individualization of treatment of young patients.

Clinical Features of Combined Central Retinal Artery and Vein Occlusion

PURPOSE

To describe the clinical features of combined central retinal artery and vein occlusion (CCRAVO).

METHODS

This retrospective study included 33 admitted patients (33 eyes) who had CCRAVO. Clinical data, such as age, gender, best-corrected visual acuity (BCVA), intraocular pressure (IOP), findings on fundus color photography and fundus fluorescein angiography (FFA), and information about follow-up, were collected and analyzed.

RESULTS

The age of the patients with CCRAVO ranged from 22 to 78 years, with a mean of 48.8 ± 14.1 years. At presentation, BCVA of the involved eyes ranged from no light perception (NLP) to 20/20. In addition, 45.5% (15/33) of the eyes had BCVA of finger counting (FC) or below, whereas 12.1% (4/33) had BCVA of 20/60 or above. The IOP was lower in the involved eyes than in the fellow eyes (15.0 ± 3.0 mmHg vs. 16.4 ± 2.3 mmHg, p=0.03). Ophthalmoscopic examination showed changes in both central retinal artery occlusion (CRAO) and central retinal vein occlusion (CRVO), including retinal hemorrhage, retinal ischemic whitening, optic disc hyperemia and/or edema, venous dilation and tortuosity, cotton wool spot (CWS), and Roth's spot. FFA showed prolonged arm-to-retina time (ART) and retinal arteriovenous passage time (RAP) (17.1 ± 4.9 s and 12.1 ± 8.8 s, respectively). Capillary nonperfusion (CNP) was seen in 21 eyes (63.6%), and in 14 (42.2%) of these, CNP was larger than 10 disc areas. At 2 to 3 weeks after presentation, BCVA improved in 23 eyes (71.9%) and further deteriorated in 5 eyes (15.6%). Retinal ischemic whitening improved in more than half of the eyes, whereas retinal hemorrhage increased in nearly half of the eyes. Follow-up ranged from 6 to 56 months. Seven patients were lost to follow-up. At final follow-up, six eyes had a visual acuity of 20/60 or greater, but 6 eyes had FC or worse. Four eyes developed neovascularization on follow-up.

CONCLUSION

CCRAVO is a sight-threatening entity. Manifestations of CRAO and CRVO can be seen simultaneously in the early stage of disease, and CRVO may play a more important role in the development of CCRAVO.

Optical Coherence Tomography Angiography of Combined Central Retinal Artery and Vein Occlusion

Optical coherence tomography angiography (OCTA) is a new, noninvasive technology that enables detailed evaluation of flow in the retinal and choroidal vasculature. The authors believe this to be the first report to describe the optical coherence tomography angiography findings associated with combined central retinal artery occlusion (CRAO) and central retinal vein occlusion (CRVO).

Combined Central Retinal Artery and Vein Occlusion Associated with Factor V Leiden Mutation and Treated with Hyperbaric Oxygen

Background

Combined central retinal artery occlusion (CRAO) and central retinal vein occlusion (CRVO) is an uncommon retinal vascular disease which causes sudden visual acuity loss and is associated with poor prognosis and the development of severe complications. We report a very rare case of combined CRAO and CRVO in a patient with factor V Leiden (FVL) mutation (only 3 cases published). To our knowledge, this is the first case of combined CRAO and CRVO treated with hyperbaric oxygen therapy (HBOT).

Case and Results

A 49-year-old woman presented with complaints of sudden loss of vision in her left eye (LE), with best corrected visual acuity (BCVA) of 1/20. A complete ophthalmic evaluation with fundus angiography showed combined CRAO and CRVO. The patient was urgently treated with HBOT (she completed a total of 9 sessions in 7 days), with marked visual acuity and angiographic improvement (BCVA of 10/10). Forty-five days later, she developed a new LE CRVO, and BCVA decreased to 5/10 and later to <1/20 because of significant macular edema. A detailed investigation showed an abnormal resistance to activated protein C, and a genetic study showed homozygosity for FVL mutation. The patient was submitted to 3 monthly injections of 1.25 mg bevacizumab. After 10 months, the patient is in a stable condition with BCVA of 6/10.

Conclusions

Combined CRAO and CRVO in young adults should be investigated thoroughly for embolic sources, thrombophilic disorders and local ocular conditions. This is the first case of this severe disease that was treated with HBOT, and the visual result was very good.

Combined CRVO with CRAO in a patient with protein C deficiency

PURPOSE

To study the underlying factors in a young patient having central retinal venous obstruction with central retinal arterial obstruction and its effects on visual outcome.

METHODS

A 33-year-old man presented with a complaint of sudden loss of vision in his right eye. A complete ophthalmic evaluation with fundus angiography showed combined central retinal venous obstruction with central retinal arterial obstruction. Detailed investigations revealed reduced (20%) functional assay of protein C suggestive of the diagnosis of severe Type II protein C deficiency with Factor V Leiden mutation. This ocular event was the first sign of the underlying disorder.

RESULTS

The ophthalmic event rapidly progressed to no perception of light. Anticoagulant therapy was started to prevent life-threatening systemic complications. Despite antiglaucoma medications, intraocular pressure was high and cyclocryotherapy was advised.

CONCLUSION

Retinal vascular disorders in the younger population have different underlying risk factors than in the older age group. Clinical presentation, severity, and management also depend on causative factors. Combined retinal artery and vein occlusion is very uncommon. Combined cases have mostly been attributed to rheological causes like thrombophilia, vessel wall inflammation, and mechanical compression. Protein C deficiency has mainly been linked to vein occlusions and there is no reference to protein C deficiency as a cause of combined central retinal venous obstruction and central retinal arterial obstruction. Combined cases usually present with severe visual loss and have rapid progression. Young patients having such presentation should be thoroughly evaluated to diagnose underlying factors and initiate appropriate management at the earliest.

Comorbidities in combined retinal artery and vein occlusions

Background

Several general diseases cause blindness in patients with simultaneous combined retinal artery and vein occlusion.

Methods/patients

We examined 14 patients with acute unilateral visual loss due to combined retinal artery and venous occlusions. All 14 patients presented at the Polyclinic over a period of about 3 years. Fluorescein angiography was carried out in 12 patients to confirm the diagnosis. Ten patients underwent Doppler sonography and 11 echocardiography.

Results

Concerning systemic diseases, 11 of our 14 patients presented several cardiovascular risk factors, i.e., immunocytoma and arterial hypertension and hypercholesterolemia in one patient; another patient had chronic bronchitis, tachycardia and hypercholesterolemia. Six patients presented coagulation anomalies, and eight patients had arterial hypertension.

Doppler sonography revealed normal carotid arteries in nine of ten patients. In 8 of 11 patients, echocardiography displayed no cardiac abnormalities.

Ophthalmoscopy revealed no emboli in any of these patients.

Conclusion

Unilateral simultaneous combined incomplete retinal artery and venous occlusions should be considered as one entity. Eleven of our patients presented comorbidities reflecting several cardiovascular risk factors. Immunological diseases, malignancies and coagulopathies can cause this ocular disorder, resulting in blindness. No emboli were found in any of these patients. Patients suffering from acute visual loss must be examined for the presence of systemic diseases to enable therapy at an early stage.

Central retinal vein occlusion with cilioretinal infarction from branch flow exclusion and choroidal arterial steal

PURPOSE

The first definitive study of retinal vein occlusion complicated by infarction within the territory of one or more cilioretinal arteries was published in 1976. Many individual cases and further case series have been reported in the interim, but the nature of the interrelationship is still under debate.

METHODS

A review was undertaken of the relevant clinical and fundus fluorescein angiographic characteristics of this combined retinal vascular disorder together with the pathophysiological mechanisms currently presented in the literature to explain their association. Scientific publications up to 2008 were evaluated by one of the authors of the original report.

RESULTS

There are broad similarities between publications in their descriptions of the clinical features, but significant differences of detail and interpretation are also evident. Most of the mechanisms so far proposed to account for cilioretinal infarction after central or hemisphere retinal vein occlusion do not withstand critical scrutiny. Two related hypotheses are expounded that appear to satisfactorily elucidate this interrelationship -- branch flow exclusion and branch flow diversion (otherwise termed "choroidal arterial steal").

CONCLUSION

In eyes with a cilioretinal supply, the probability that cilioretinal infarction will complicate retinal vein occlusion increases with increasing severity of venous obstruction and the more distally the cilioretinal artery arises from the posterior ciliary arterial tree. A distal branch point also facilitates observation of dye front reciprocation within the artery. Indicators of the degree of venous obstruction that may be necessary to instigate cilioretinal infarction include very prolonged dye transit times in the central retinal circulation, exaggerated venous cyanosis and tortuosity, perivenous cotton-wool sentinels, and macular perivenular whitening.

The management of retinal vein occlusion: is interventional ophthalmology the way forward?

Retinal vein occlusions (RVO) are the second commonest sight threatening vascular disorder. Despite its frequency treatments for RVO are unsatisfactory and include several that have not been tested by large, well designed, prospective, randomised controlled trials. There is also the lack of long term follow up in many of the available small uncontrolled studies, and the timings of interventions are haphazard. This review aims to evaluate the current knowledge relating to the pathogenesis, suggested treatments for the different types of RVO, and their complications. Isovolaemic haemodilution is of limited benefit and should be avoided in patients with concurrent cardiovascular, renal, or pulmonary morbidity. Evidence to date does not support any therapeutic benefit from radial optic neurotomy, optic nerve decompression, or arteriovenous crossing sheathotomy on its own. Vitrectomy combined with intravenous thrombolysis may offer promise for central RVO. Similarly, vitrectomy combined with arteriovenous sheathotomy intravenous tissue plasminogen activator may offer benefits for branch RVO. RVOs occur at significantly high frequency to allow future prospective randomised controlled studies to be conducted to evaluate the role of different therapeutic modalities singly or in combination.