7, 8 Schultz and colleagues reported final visual acuity of 20/50 or better in 12 of 16 patients managed with observation alone. Vitreous hemorrhage usually clears within 1 year but may remain for as long as 6 years. In most cases, these hemorrhages clear spontaneously, albeit slowly. Conditions Causing Retinal Neovascularization
#Dot blot hemorrhage eye series#
In a recent prospective series of 100 patients with subarachnoid hemorrhage, patients with intraocular hemorrhage were much more likely to have experienced coma than those without ocular involvement (89% versus 46%). 5 Although mortality rates have diminished substantially in the 25 years since publication of that study, it remains likely that intraocular hemorrhage correlates with the severity of injury. In one retrospective study of 320 patients with subarachnoid hemorrhage, those with associated intraocular hemorrhage had a significantly higher mortality rate (53.6%) than those without intraocular hemorrhage (19.7%). The presence of intraocular hemorrhages may have prognostic as well as diagnostic value. Vitreous hemorrhage may be dense enough to obscure visualization of the posterior pole. Larger areas of hemorrhage beneath the internal limiting membrane or posterior hyaloid face, sometimes assuming an elevated or dome-shaped appearance, also may occur. 6 Typically, multiple blot-shaped retinal hemorrhages are seen in the peripapillary and macular regions. This acute rise in intraocular pressure in turn causes compression of the central retinal vein and blockage of retinal venous outflow, which leads to rupture of retinal capillaries. It is thought that intracranial hemorrhage leads to increased intracranial pressure, which is transmitted along the subdural space of the optic nerve. The exact pathogenesis of Terson syndrome is still unknown. 2– 4 Some type of intraocular hemorrhage (subretinal, intraretinal, preretinal, or vitreous) may be seen in up to 20% of patients with subarachnoid or subdural hemorrhage. Terson syndrome is the term used to describe the specific association of intracranial and vitreous hemorrhages 1 and has been found to occur in 3 to 8% of patients with subarachnoid hemorrhage. Treatment and timing of treatment are determined by the underlying condition causing the vitreous hemorrhage as well as by the patient’s level of functioning and systemic health. Ultrasound examination may disclose a retinal break, retinal detachment, or retinal or choroidal mass, or an elevated area of neovascularization. Careful funduscopy often reveals the source of the bleeding, but in cases of dense vitreous hemorrhage, B-scan ultrasonography is valuable for visualizing the posterior segment. This neovascularization is most commonly seen as a sequela of diabetic retinopathy or retinal occlusive disease (see later discussion) but may occur as part of the body’s compensatory response to any condition that produces retinal ischemia. Vitreous hemorrhage most often stems from bleeding from an area of preretinal or intraretinal neovascularization ( Table 12–1). The source of the blood can be (1) subretinal vessels (e.g., from choroidal neovascularization in age-related macular degeneration or from a choroidal tumor) (2) an avulsed, native retinal blood vessel (e.g., caused by a retinal break or direct trauma) or (3) fragile, proliferative preretinal new vessels. What Are the Sources of Vitreous Hemorrhage?īlood in the vitreous cavity may be as mild as a suspension of pigmented cells or as severe as to cause complete obscuration of any fundus detail. The guidelines provided are intended as a framework for clinical evaluation and therapeutic considerations to be thought out carefully in the context of the individual patient. The clinical entities discussed in this chapter are common and important conditions most likely to be encountered in daily practice. For this reason, accurate diagnosis and appropriate care for the patient with hemorrhage of the posterior segment require a thorough medical history, review of systems, and careful and complete examination of both eyes. The presence of hemorrhage in the posterior segment may cause significant visual disturbance and may signify a serious ocular or systemic abnormality.
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