VHL Handbook

What You Need to Know about VHL

VHL in the Retina

When capillaries form angiomas, technically called hemangioblastomas, in the retina, they start out extremely small and difficult to see. The capillaries themselves are less than the diameter of a red blood corpuscle, one of the cells that make up the blood.

When angiomas begin, they often grow around the equator or periphery of the retina, far away from the area of central vision. Unlike the equator drawn around the globe of the world, the equator of the eye is vertical. As you stand, draw a circle around your eye from eyebrow to nose and around. The circle you just drew is the equator. To see this area, your ophthalmologist or optometrist must dilate your eye, use high-powered magnifying lenses, and look from side angles. It is more than the usual eye examination. (see Figure 4.) If there is VHL in your family, be sure to tell your ophthalmologist or optometrist so that he or she will be sure to do this thorough examination and find any small angiomas so that they can be treated in the early stages. A referral to a retinal specialist will be required for treatment of these tumors.

Figure 4: Ophthalmologist exploring the equator of the eye with indirect ophthalmoscope. Illustration by Vincent Giovannuci, O.D.

Not all ophthalmologists and optometrists are familiar with this uncommon disorder. You should look for an eye care professional who is familiar with VHL and qualified to perform a thorough dilated examination of the fundus and periphery with an indirect ophthalmoscope.

The objective of treatment is to keep the angioma so small that it does not affect your vision. Treatments generally include laser treatment (light surgery) or cryotherapy (freezing). Leaflets on these treatments are produced by the American Academy of Ophthalmology and other professional associations, and are usually available from your ophthalmologist. Both treatments are trying to keep the angioma from growing.

Sixty percent (60%) of people with VHL have retinal lesions. People as young as 3, and sometimes even younger, can be affected, making screening children very important. Children who have a positive DNA diagnosis of VHL should be screened for eye lesions beginning at age 1.

New angiomas can occur throughout life so that regular eye exams in affected individuals are important. Generally smaller lesions can be treated more successfully and with fewer complications than larger ones. Leakage or bleeding from larger angiomas can lead to serious vision damage or retinal detachment, so early treatment and careful management are very important.

Lesions on or near the optic nerve are very difficult to treat successfully and should not be approached with laser. Fortunately, they tend to grow slowly. Contact the VHL Family Alliance for the latest recommendations.

References:

American Academy of Ophthalmology, online brochures: “Laser Surgery in Ophthalmology,” and “Cryotherapy,” AAO, P.O. Box 7424, San Francisco, CA 94120-7424. +1 415 561-8500. http://www.aao.org

Chew, Emily, et al., von Hippel-Lindau disease: clinical considerations and the use of fluorescein-potentiated argon laser therapy for treatment of retinal angiomas. Seminars in Ophthalmology. 7(3):182-91, 1992 Sep.

The National Eye Institute (nei.nih.gov) and the National Library of Medicine (nlm.nih,gov) are both excellent resources for new terms and treatments.

Dollfus H, Massin P, Taupin P, Nemeth C, Amara S, Giraud S, Beroud C, Dureau P, Gaudric A, Landais P, Richard S, Ocular manifestations in von Hippel-Lindau disease: a clinical and molecular study. Invest. Ophthalmol. Vis Sci, 2002, 43: 3067-74. PMID: 12202531

Gaudric A, Krisvosic V, Duguid G, Massin P, Giraud S, Richard S, Vitreoretinal surgery for severe retinal capillary hemanbioglastomas in von Hippel-Lindau disease. Ophthamology, 2011, 118: 142-9. PMID: 20801520

Wong WT, Chew EY. Ocular von Hippel-Lindau disease: clinical update and emerging treatments. Curr Opin Ophthalmol. 2008 May;19(3):213-7. Review. PMID: 18408496