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A complicated well-regulated balance exists between the thrombosis and fibrinolysis systems. This chapter will cover the two main categories of retinal vascular occlusive disease (RVOD): central (CVO) or branch retinal vein occlusion (BVO) and central (CAO) or branch retinal artery occlusion (BAO). This chapter will not address the overall diagnostic evaluation of patients with retinal vascular disease. Patients with CAO/BAO should be evaluated by their medical doctor for common underlying causes such as ipsilateral carotid disease and heart disease. Patients with bilateral, simultaneous CVO/BVO of course should be evaluated for common causes of hypercoagulable states such as Waldenström’s or multiple myeloma. Basic evaluation should include a medical review of systems, testing for high blood pressure and diabetes for all patients, and sedimentation rate, carotid Doppler and cardiac sonogram should always be obtained for retinal arterial disease (RAO). After a basic evaluation, many patients with RAO or retinal venous disease (RVO) are said to have idiopathic conditions. In recent years, there have been a large number of papers citing possible associations of RAO and RVO with abnormalities of plasma proteins. Are these associations real? Which should be considered and looked for in which patients? It will be some years before we can offer clear guidance on this subject, and there is a strong need for large prospective studies with contemporaneous well-matched control groups. Until these studies are available, in this chapter we summarize the pertinent literature and offer some thoughts on whether and how patients with RAO and RVO who do not have obvious causes after a “basic” evaluation should be worked up.

Idiopathic juxtafoveolar retinal telangiectases (IJRT) were classified by Gass and Oyakawa in 1982 using biomicroscopic and fluorescein angiographic data [ 6 ]. This classification was updated by Gass and Blodi in 1993 [ 5 ], who subdivided IJRT into three groups (Table 22.1.1). Group 1 IJRT are unilateral in most cases and characterized by dilated retinal capillaries and abnormal leakage leading to an easily visible exudation. Group 2 IJRT are mostly bilateral and characterized by late staining on fluorescein angiography with minimal exudation. Later in the disease process retinal pigment epithelial proliferation or secondary subretinal neovascularization may develop. In Group 3 changes are based on bilateral capillary occlusion. These changes lead to easily visible telangiectasis, parafoveolar capillary occlusion and minimal exudation.

Uveal melanomas present in adulthood, their incidence peaking at around the age of 60 years [ 4 ]. More than 90% of uveal melanomas arise in choroid, about 40% extending close to optic disk or fovea. These tumors tend to cause visual loss from retinal pigment epithelial disease, macular edema, and exudative retinal detachment (Fig. 23.1). In advanced cases, the presence of a large intraocular tumor and extensive retinal detachment can result in rubeosis, neovascular glaucoma, phthisis, and a blind and painful eye. Approximately 50% of patients develop metastatic disease, which usually involves the liver and which is usually fatal within a few months.

Purtscher’s retinopathy was first described by Otmar Purtscher in 1910 as a syndrome of multiple, white retinal patches, superficial retinal hemorrhages, and papillitis occurring in five patients with severe head trauma [ 11 ]. He originally named this condition angiopathia retinae traumatica and hypothesized that white, superficial retinal patches were lymphatic extravasations caused by a sudden increase in intracranial pressure secondary to massive head trauma.

Henry Eales, a British ophthalmologist, described this condition almost 125 years ago [ 14 , 15 ]. Eales’ original description was of recurring retinal and vitreous hemorrhages along with epistaxis, headaches, variation in peripheral circulation, dyspepsia, and chronic constipation in young men. He felt it was a vasomotor neurosis, wherein constriction of the alimentary vessels resulted in compensatory dilatation of the vessels in the head, leading to bleeding. Though Eales was honored with the eponym for this disease, Wadsworth was the first to describe the presence of retinal inflammation, 5 years later [ 37 ]. Duke Elder considered Eales’ disease to be a clinical manifestation of many diseases.

The classification of fundus changes secondary to arterial hypertension has been used for monitoring the severity of vascular alterations. In the past, this was the only possibility to assess the status of the microcirculation. Therefore, very detailed classifications have been developed. These classifications are described below. The detailed classification of hypertensive vascular fundus changes may be still important for scientific reasons. However, for the clinical management of systemic hypertension today these detailed classifications are no longer necessary. Nevertheless, the separation between minor vascular changes in systemic hypertension (stage I and II) and hypertensive retinopathy (stage III and IV) is still very important for the management of arterial hypertension. Patients with hypertensive retinopathy have to be treated and monitored intensively by internal medicine since these patients are at high risk for cardiovascular and cerebrovascular complications.

Sickle cell hemoglobinopathies all share the common feature of an abnormal globin chain, which leads to sickling of erythrocytes and obstruction of the microcirculation. Sickle vaso-occlusive events are insidious and affect virtually every vascular bed in the eye, often with visually devastating consequences. Vaso-occlusion most profoundly affects the retina, the light-sensitive tissue that lines the inside wall of the posterior aspect of the eye, because it is exquisitely sensitive to deprivation of oxygen. Even temporary vaso-occlusion, if longer than about 1.5–2 h, can result in permanent infarction of the retina. Most, if not all, of the complications of sickle cell disease in retina originate from the vaso-occlusive processes. The pathological changes can be divided into nonproliferative and proliferative events.

These congenital, non-progressive lesions are benign, and often solitary and unilateral. Patients are usually asymptomatic, although some may experience decreased vision and neurologic symptoms, such as seizures and cranial nerve palsies [ 15 , 87 ]. Cutaneous or cerebral hemangiomas may also be found, especially in cases of inherited lesions [ 2 , 4 , 15 , 22 , 23 , 58 ]. Pedigree analysis suggests that this neurooculocutaneous syndrome may be inherited in an autosomal dominant pattern, with incomplete penetrance or variable expressivity [ 23 , 58 ].