Several vascular tumors and malformations can affect the uveal tract. The most important is choroidal hemangioma, which can occur as a circumscribed tumor or as a diffuse lesion in patients with variations of the Sturge-Weber syndrome. This section covers the subject of circumscribed choroidal hemangioma, a benign vascular tumor that has been the subject of considerable attention in the literature (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45). Its etiology in unknown, but it is usually diagnosed in adulthood when it becomes symptomatic. It is speculated that some cases may be congenital or develop in early childhood. Circumscribed choroidal hemangioma usually has typical clinical features.

Circumscribed choroidal hemangioma is almost always unilateral. It appears as a subtle, red-orange mass in the posterior choroid. It can produce visual loss because of a subfoveal location or a secondary retinal detachment that involves the fovea (1, 2, 3, 4, 5, 6). It can induce hyperplasia and fibrous metaplasia of the overlying pigment epithelium, which can sometimes lead to diagnostic confusion with melanoma. In addition to retinal detachment, secondary retinoschisis commonly occurs over or adjacent to the tumor. Occasionally, neovascular glaucoma can develop, and the subsequent pain may necessitate enucleation (8,45).

Fluorescein angiography typically shows hyperfluorescence of the tumor blood vessels in the pre-arterial phase and diffuse late staining of the mass (1,2,6,11). Indocyanine green angiography reveals early filling of the lesion and a characteristic “wash out” of the hyperfluorescence in the later frames (12,22,27). A-scan ultrasonography shows high internal reflectivity within the tumor, and B-scan ultras onography shows a placoid or ovoid choroidal mass pattern with acoustic solidity. Ultrasonography occasionally demonstrats a highly reflective plaque over the tumor surface, which corresponds to fibrous or osseous metaplasia of the overlying RPE (2). Computed tomography and magnetic resonance can also demonstrate choroidal hemangioma, but the results are not necessarily diagnostic. With MRI, choroidal hemangioma generally differs from other intraocular tumors in that it is hyperintense to vitreous on T1-weighted images and isointense on T2-weighted images. Most other intraocular tumors are hypointense on T2 images (2).

Grossly, a circumscribed choroidal hemangioma is a red placoid or ovoid choroidal tumor. Microscopically, it is usually composed of large congested blood vessels separated by rather thin intervascular septae. Overlying cystoid retinal edema and retinoschisis are consistent features over choroidal hemangiomas that come to histopathologic examination (2,3).

There have been a number of recent publications on the management of circumscribed choroidal hemangioma. If the affected patient is asymptomatic, no treatment is necessary. When there is visual loss because of a serous detachment of the fovea, the traditional treatment has been laser photocoagulation to the tumor surface to induce resolution of the subretinal fluid (1,2,4,13,15). Plaque or external beam radiotherapy can be employed in cases with more advanced detachment (16, 17, 18, 19, 20,37,38). Plaque radiotherapy has been effective in treating choroidal hemangioma with total retinal detachment resulting in reattachment of the retina (17). External beam irradiation, delivering about 2000 cGy to the whole eye, has been effective in bringing about a decrease in tumor thickness and resolution of the retinal detachment for both circumscribed and diffuse choroidal hemangioma.

There has been recent enthusiasm for other methods of treatment. Transpupillary thermotherapy has met with some success (23, 24, 25, 26,33,41). In recent years, a number of authors have reported good results with photodynamic therapy (PDT), using a method similar to that used for age-related macular degeneration (28,29,31, 32, 33, 34). Optical coherence tomography has been used to document the presence of cystoid retinal edema and subretinal fluid before and after PDT. We have seen a dramatic resolution of these findings and a significant return of vision in a number of patients treated with PDT. In rare instances, neovascular glaucoma may necessitate enucleation (7).

In most instances, the characteristic orange color of a circumscribed choroidal hemangioma strongly suggests the diagnosis.

In some instances, circumscribed choroidal hemangioma can cause secondary hyperplasia, fibrous metaplasia, or osseous metaplasia of the retinal pigment epithelium, as well as secondary retinal detachment and secondary retinoschisis.

Although the findings are not pathognomonic, fluorescein angiography and indocyanine green angiography can often be helpful in differentiating a choroidal hemangioma from amelanotic melanoma, choroidal metastasis, and other nonpigmented fundus tumors.

Ultrasonography of choroidal hemangioma generally shows high internal reflectivity with A-scan and acoustic solidity with B-scan. Fibrous or osseous metaplasia of the overlying pigment epithelium can produce a highly reflective echo that can sometimes confuse the diagnosis.