Preretinal, subhyaloid and vitreous hemorrhages are largely controlled by gravity. Like vitreous hemorrhages, subhyaloid and preretinal hemorrhages also block underlying retinal features and can reduce visual acuity when located near the macula. Thus, hemorrhages in both of these locations have more defined structural boundaries and are often indistinguishable ( Figure 1). Preretinal anatomical boundaries also exist between the internal limiting membrane and the retinal nerve fiber layer (RNFL). The subhyaloid is located between the posterior limiting layer of the vitreous and the internal limiting membrane (ILM) of the retina. A fresh vitreous hemorrhage often appears bright red, and turns to a more white or cream color due to red blood cell dehemoglobinization over time. Upon clinical evaluation, this may lead to a “hazy” appearing fundus due to the collection of red blood cells floating in the vitreous, especially in acute cases. Due to the lack of boundaries, these hemorrhages tend to diffuse throughout the vitreous and, in chronic cases, can settle inferiorly. A vitreous hemorrhage represents leakage of blood in and around the vitreous humor. Starting anteriorly, the classification of hemorrhages based on depth includes:ġ. These, along with distribution of the hemorrhage, can give clues to the etiology and help uncover possible systemic comorbidities. To begin, clinicians should document the location and depth with respect to the vitreal-retinal-choroidal interfaces. Shape, location and size, as well as associated signs and symptoms, are all key to properly classifying a retinal hemorrhage. This preretinal hemorrhage forms a boat shape and blocks underlying retinal vasculature detail. 1 A look at the clinical presentation of retinal hemorrhages and the pathophysiology that leads to their correct identification and classification can help you work through the differential diagnoses and decide whether to monitor or refer.įig. In addition, they can be idiopathic ( Table 1 ). Such damage can be caused by vascular disease, hematologic disorders and dyscrasias, infections, trauma or hypoxia. Because of the blood-retinal barrier, which aids in isolating blood from the retina to avoid retinal toxicity, hemorrhages within the retina are rare unless there is insult to the ocular or systemic vasculature. Retinal hemorrhages, often first diagnosed in the primary eye care setting, can be a presenting finding in many ocular and systemic disease states. The Larry Alexander Resident Case Report Contest: Cloudy with a Chance of Retinopathy
Dot blot hemorrhage vs microaneurysm update#
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