Symptoms of Posterior Vitreous Detachment
During the process of PVD, patients may experience symptoms of floaters or flashing lights, or both. Classically, the flashing light (also known as Moore lightning streaks) consists of a dim white or golden arc of light in the temporal periphery that is usually visible only under dim lighting conditions. Flashing lights of other description should alert the clinician to other etiologies. The pathogenesis of the flashes is not fully understood; traction on the retina during vitreous separation, or the impingement of the vitreous body onto the retina during eye movement have been suggested, but these would not explain the uniform temporal location of the flashes.[27,28] Stimulation of the optic nerve head as the PHM pulls away in the early stages of PVD may be a more plausible source of the symptoms, particularly as flashing lights frequently precede separation of the PHM from the optic disk.
Floaters are usually most noticeable when looking against a light background; they can take on different shapes and sizes, and they can appear in different combinations. Vitreous fibrillar condensations give rise to thread-like opacities, while the Weiss ring may cause a ring, tadpole, or large solitary floater. The PHM itself can sometimes cause a veil-like effect. In PVDs complicated by vitreous hemorrhage, the patient may notice a red haze or mist, or multiple small floaters with or without larger streak floaters, depending on the severity of the hemorrhage.
A PVD may not always be present despite the presence of floaters. This is especially true for younger myopic subjects (< 50 years old), in whom floaters are usually the more common complaint. In these subjects, no significant difference in PVD prevalence can be found when compared to asymptomatic subjects of the same age group.[24,29] In older patients, however, symptoms are more predictive of a PVD. Overall, a combination of a single temporal arc of flashing light and floaters is most predictive of a PVD. In subjects with these symptoms, PVD is present in 88% to 100% of cases.[29] In addition, not all patients with PVD experience symptoms. In the same study, examination of fellow asymptomatic eyes revealed the presence of PVD in 20% of cases.[29]
In the majority of patients, PHM separation from the retina occurs uneventfully. However, up to one in five PVDs is associated with complications that may or may not need further treatment.[24,30,31,32,33]
© 2005 Comprehensive Ophthalmology Update, LLC
Cite this: Posterior Vitreous Detachment: Current Concepts and Management - Medscape - Jul 01, 2005.