18.
Anomalous PVD and Vitreoschisis
Jerry Sebag (Huntington Beach)
Invisible by design1, vitreous is a viscoelastic extracellular matrix that is normally a gel
because of the intricate organization of its macromolecular components2. During aging, there
is liquefaction of the gel and weakening of vitreo-retinal adhesion, resulting in posterior vitreous
detachment (PVD). Liquefaction without concurrent vitreo-retinal dehiscence results in
Anomalous PVD 3. The clinical manifestations of Anomalous PVD vary, depending upon where
traction is exerted. In the periphery, retinal tears and detachments result while at the optic
disc, anomalous PVD contributes to diabetic vitreo-retinopathy4. At the macula, there can be
vitreo-macular traction syndrome, a phenomenon which may play a role in exudative age-related
macular degeneration5. A split in the posterior vitreous cortex, known as vitreoschisis, may
play a role in the development of macular holes and pucker.6 Studieshave shown that about half
of patients with macular hole and macular pucker have evidence of vitreoschisis on combined OCT-SLO imaging7. Thus, the
unifying concept of anomalous PVD provides insight into disease pathogenesis and guides new avenues of research and
development, such as Pharmacologic Vitreolysis.8
1. Sebag J: Classifying Posterior Vitreous Detachment - a new way to look at the invisible. Brit J Ophthalmol 81:521-522, 1997.
2. Sebag J: Macromolecular structure of vitreous, In: Polymer Science and the Eye (TV Chirila, ed). Prog Polym Sci 23:415-446, 1998.
3. Sebag J: Anomalous PVD – a unifying concept in vitreo-retinal diseases. Graefes Arch Clin Exp Ophthalmol 242:690-698, 2004.
4. Kroll P, Rodrigues E, Hoerle S: Pathogenesis and classificaton of proliferative diabetic vitreoretinopathy. Ophthalmologica. 221:78-94, 2007.
5. Krebs I, Brannath W, Glittenberg K, Zeiler F, Sebag J, Binder S: Posterior vitreo-macular adhesion: a potential risk factor for exudative agerelated
macular degeneration. Am J Ophthalmol 144:741-746, 2007.
6. Sebag J: Vitreoschisis. Graefes Arch Clin Exp Ophthalmol 246:329-32, 2008.
7. Sebag J, Gupta P, Rosen R, Garcia P, Sadun AA: Macular holes and macular pucker: The role of vitreoschisis as imaged by optical coherence tomography/
scanning laser ophthalmoscopy. Trans Am Ophthalmol Soc 105:121-131, 2007.
8. Sebag J: Pharmacologic vitreolysis. Retina 18:1-3, 1998.