CHAPTER 18

Angiomatous Tumors

Hemangiomas

Choroidal Hemangiomas

Hemangiomas of the choroid occur in 2 specific forms: circumscribed and diffuse. The circumscribed choroidal hemangioma is a benign vascular tumor that typically occurs in patients with no systemic disorders. It generally appears as a red or orange tumor located in the postequatorial zone of the fundus, often in the macular area (Fig 18-1). Such tumors commonly produce a secondary retinal detachment that extends into the foveal region, resulting in blurred vision, metamorphopsia, and micropsia. These tumors characteristically affect the overlying retinal pigment epithelium (RPE) and cause cystoid degeneration of the outer retinal layers.

Figure 18-1 A, Circumscribed choroidal hemangioma (arrows). B, A-scan ultrasound study shows characteristic high internal reflectivity (arrow). C, B-scan ultrasound study shows a highly reflective tumor (asterisk).

contrasts markedly with the color of the unaffected fundus (B) of the same patient.

The diffuse choroidal hemangioma is generally seen in patients with Sturge-Weber syndrome (encephalofacial angiomatosis). This choroidal tumor produces diffuse reddish orange thickening of the entire fundus, resulting in an ophthalmoscopic pattern commonly referred to as tomato ketchup fundus (Fig 18-2). Retinal detachment and glaucoma often occur in eyes with this lesion. See also Chapter 12 in this volume, BCSC Section 12, Retina and Vitreous, and BCSC Section 6, Pediatric Ophthalmology and Strabismus.

Ancillary diagnostic studies may be of considerable help in evaluating choroidal hemangiomas. Fluorescein angiography reveals the large choroidal vessels in the prearterial or arterial phases with late staining of the tumor and the overlying cystoid retina. Ultrasonography is helpful in differentiating choroidal hemangiomas from amelanotic melanomas and other simulating lesions. A- scan ultrasonography generally shows a high-amplitude initial echo and high-amplitude broad internal echoes (high internal reflectivity; see Fig 18-1B). B-scan ultrasonography demonstrates localized or diffuse choroidal thickening with prominent internal reflections (acoustic heterogeneity) without choroidal excavation or orbital shadowing (Fig 18-1C). Radiographic studies, particularly CT scanning, can be helpful in differentiating a choroidal hemangioma from a choroidal osteoma.

Asymptomatic choroidal hemangiomas require no treatment. The most common complication of both circumscribed and diffuse choroidal hemangiomas is serous detachment of the retina involving the fovea, with resultant vision loss. Traditionally, circumscribed choroidal hemangiomas have been managed by laser photocoagulation. The surface of the tumor is treated lightly with laser photocoagulation to create chorioretinal adhesions that prevent further accumulation of subretinal fluid. If the retinal detachment is extensive, photocoagulation is often unsuccessful. Recurrent detachments are common, and the long-term visual prognosis in patients with macular detachment or edema is guarded. Laser photocoagulation has recently been replaced by photodynamic therapy (PDT) as the primary treatment for symptomatic circumscribed choroidal hemangioma.

PDT involves an intravenous infusion of verteporfin (6 mg/m2), which is followed by an application of diode laser (689 nm) 15 minutes later at a light dose of 50 J/cm2 for a duration of 83 seconds. Most authors have reported resolution of the subretinal fluid, improvement in visual acuity, and regression of the lesion with this treatment.

Radiation, in the forms of brachytherapy, charged-particle, and external beam, has been used to treat choroidal hemangiomas. Brachytherapy and charged-particle therapy have been used to treat patients with circumscribed choroidal hemangioma, and external-beam radiotherapy (low dose, fractionated) has been used to treat patients with diffuse choroidal hemangioma. Each modality has been reported to cause involution of the hemangiomas, with subsequent resolution of the associated serous retinal detachment. Complications from the radiation and the serous retinal detachment may limit vision in patients who are irradiated.

To date, little data have been published to support the use of vascular endothelial growth factor (VEGF) inhibitors in the treatment of choroidal hemangiomas.

Boixadera A, García-Arumí J, Martínez-Castillo V, et al. Prospective clinical trial evaluating the efficacy of photodynamic therapy for symptomatic circumscribed choroidal hemangioma. Ophthalmology. 2009;116(1):100–105.

Retinal Angiomas

Capillary hemangioblastoma

Retinal capillary hemangioblastoma (angiomatosis retinae, previously known as retinal capillary hemangioma) is a rare autosomal dominant condition with a reported incidence of 1 in 40,000.

Typically, patients are diagnosed in the second to third decades of life, although retinal lesions may be present at birth. The retinal capillary hemangioblastoma appears as a red to orange tumor arising within the retina with large-caliber, tortuous afferent and efferent retinal blood vessels (Fig 18-3). Associated yellow-white retinal and subretinal exudates that have a predilection for foveal involvement may appear. Exudative detachments often occur in eyes with hemangioblastomas. Atypical variations include hemangiomas arising from the optic disc, which may appear as encapsulated lesions with or without pseudopapilledema, and in the retinal periphery, where vitreous traction may elevate the tumor from the surface of the retina, giving the appearance of a free-floating vitreous mass. Fluorescein angiography of retinal capillary hemangioblastomas demonstrates a rapid arteriovenous transit, with immediate filling of the feeding arteriole, subsequent filling of the numerous fine blood vessels that constitute the tumor, and drainage by the dilated venule. Massive leakage of dye into the tumor and vitreous can occur.

When a capillary hemangioblastoma of the retina occurs as a solitary finding, the condition is generally known as von Hippel disease. This condition is familial in about 20% of cases and bilateral in about 50%. The lesions may be multiple in 1 or both eyes. If retinal capillary hemangiomatosis is associated with a cerebellar hemangioblastoma, the term von Hippel–Lindau syndrome is applied. The gene for von Hippel–Lindau syndrome has been isolated on chromosome 3. A number of other tumors and cysts may occur in patients with von Hippel–Lindau syndrome. The most important of these lesions are cerebellar hemangioblastomas, renal cell carcinomas, and pheochromocytomas. Genetic screening now allows for subtyping of patients with von Hippel–Lindau to determine the risk for systemic manifestations of the disease. When this diagnosis is suspected, appropriate genetic consultation and screening are critical for long-term follow-up of ocular manifestations and the associated systemic complications. Screening for systemic vascular anomalies (eg, cerebellar hemangioblastomas) and malignancies (eg, renal cell carcinoma) may reduce mortality, while aggressive screening for and early treatment of retinal hemangioblastomas may reduce late complications of exudative detachment and improve long-term visual outcomes.

Figure 18-3 Retinal capillary hemangioblastoma. A, Note the dilated, tortuous retinal vessels (feeder artery and draining vein) emanating from the optic disc. B, These tumors may be located anywhere in the fundus and may exhibit red, orange, or

yellow coloration. (Courtesy of Robert H. Rosa, Jr, MD.)

The treatment of retinal capillary hemangioblastomas includes photocoagulation for smaller lesions, cryotherapy for larger and more peripheral lesions, and scleral buckling with cryotherapy or penetrating diathermy for extremely large lesions with extensive retinal detachment. External-beam