By Paul T. Finger, MD
Hemangiomas typically grow within the blood vessel layer beneath the retina called the choroid. If they are located in the macula (center of vision) or they leak fluid (which causes a retinal detachment or cystic changes in the retina), they can affect your vision. Many choroidal hemangiomas never grow or leak fluid and may be observed without treatment. Choroidal hemangiomas are not cancers and never metastasize.
Choroidal hemangioma are typically reddish to orange. Choroidal hemangioma can have areas of increased pigmentation which (in those cases) can make them difficult to differentiate from choroidal melanomas. Choroidal hemangiomas can cause far-sightedness (hyperopia), distorted vision (metamorphopsia), flashing lights, or blurred vision. Many choroidal hemangioma cause no symptoms at all, and are found on routine dilated eye examinations (ophthalmoscopy).
Intraocular photography and angiography: Eye-care specialists perform studies of the blood vessels in the eye with synthetic organic dyes called fluorescein or indocyanine green. The dyes are injected into the arm or hand and travel to the blood vessels inside the eye. If a tumor is in the eye, we can see specific characteristics of its circulation which can help us differentiate between it and other types of tumors. Choroidal hemangioma often have a unique pattern of circulation where the large blood vessels produce a “COARSE VASCULAR PATTERN.”
Ultrasound: Sound waves can also be used to examine the inside of the eye. Choroidal hemangioma are made up of relatively large and well-formed blood vessels. Each one of those blood vessels can reflect sound waves producing characteristically intense reflections (HIGH INTERNAL REFLECTIVITY) from within the choroidal hemangioma. High internal reflectivity is characteristic of choroidal hemangioma.
Circumscribed choroidal hemangioma can be photographed and followed for evidence of growth or leakage prior to treatment. If choroidal hemangioma are documented to be growing into the center of vision or are causing a retinal detachment, or angle-closure glaucoma they can be treated (in an effort to save vision).
Hot or thermal laser photocoagulation had been used to decrease the amount of fluid leaking out of choroidal hemangioma. Unfortunately, most patients have recurrent problems (retinal detachment, cystoid retinal degeneration) after this treatment and suffered loss of vision.
Photodynamic Therapy (PDT) is a cold or non-thermal laser treatment that involves injecting a light-sensitive dye into the patient and then shining a dye-activating PDT laser light on the choroidal hemangioma. The light-activated dye causes the abnormal blood vessels to close, shrink, and stop leaking. PDT offers a method to treat leaking posterior choroidal hemangiomas without the long-term risks of radiation. However, PDT is primarily used for another disease called wet or exudative macular degeneration (AMD). Due to changes in the treatment of SMD, fewer and fewer PDT laser machines currently exist.
Radiation Therapy: There are circumstances where PDT does not work, is unavailable or the tumor cannot be seen within the eye (usually due to a large retinal detachment). In these cases, either external beam radiation therapy or ophthalmic plaque brachytherapy may be employed. Choroidal hemangiomas and their associated retinal detachments have been cured.
Choroidal Hemangioma are benign tumors made up of blood vessels. Since choroidal hemangioma do not metastasize (spread to other parts of the body), we are more concerned with damage or changes they can cause within the eye. Choroidal hemangioma can change a patient’s vision by displacing the retina causing hyperopia (far-sightedness), causing degeneration of the overlying retina (cystoid degeneration), or by leaking fluid under and detaching the retina (serous retinal detachment).
Most choroidal hemangioma are treated if they induce a retinal detachment. Also in rare cases, choroidal hemangioma can fill most of the eye or be associated with the Sturge-Weber Syndrome. In these cases, the choroidal hemangioma can cause angle closure glaucoma. In these cases, radiation and glaucoma treatments may be warranted.