Retinal Capillary Hemangioma: Diagnosis and Treatment
Understanding Retinal Capillary Hemangioma
A retinal capillary hemangioma, also called a retinal hemangioblastoma, is a small vascular tumor made up of abnormal blood vessels in the retina. These tumors appear as reddish-pink growths with enlarged feeder arteries bringing blood in and dilated veins draining blood out. They are composed of tangled, large-diameter capillaries separated by specialized stromal cells. They typically have a characteristic 'light bulb' appearance on examination.
Most retinal capillary hemangiomas develop in the peripheral retina, particularly in the upper and lower outer regions known as the superotemporal and inferotemporal quadrants. Some tumors grow on or near the optic disc, the spot where the optic nerve connects to the retina. Although these tumors are benign, they can leak fluid, cause swelling, and lead to vision-threatening complications over time.
Retinal capillary hemangioma is closely linked to von Hippel-Lindau (VHL) disease, a genetic condition that causes tumors and cysts to grow in multiple organs. VHL disease follows an autosomal dominant inheritance pattern, meaning a child has a 50 percent chance of inheriting it if one parent carries the gene mutation. VHL disease occurs in approximately 1 in 36,000 live births (AAO).
The frequency of retinal capillary hemangiomas in people with VHL disease ranges from 49% to 85% (Retina Today). However, not everyone with a retinal capillary hemangioma has VHL disease. The probability of VHL disease in patients with a single retinal capillary hemangioma has been estimated at roughly 46% (AAO). This is why genetic testing is strongly recommended for anyone diagnosed with this tumor.
In VHL-associated cases, a mutation in the VHL tumor suppressor gene on chromosome 3p25-26 leads to a loss of normal protein function. Without functional VHL protein, a substance called hypoxia-inducible factor (HIF) builds up in cells. HIF moves into the cell nucleus and activates genes that produce vascular endothelial growth factor (VEGF) and other signals that promote blood vessel growth.
This overproduction of VEGF drives the formation of abnormal blood vessels, causes existing vessels to dilate and leak, and stimulates the growth of endothelial and stromal cells that make up the tumor. In cases not associated with VHL disease, the exact trigger is less well understood, but the same pathway of abnormal blood vessel growth is believed to play a role.
Who Is Affected and Risk Factors
Retinal capillary hemangiomas are most commonly detected between the ages of 15 and 35. The median age at diagnosis in patients with VHL disease is approximately 17.6 years, with a range from 2.8 to 46.7 years (NIH/PMC). In patients without VHL disease, the median age at diagnosis is older, around 36.1 years, with a range from 7 to 74 years.
Most new retinal capillary hemangiomas develop by the age of 47 years. This means regular screening is especially important for at-risk individuals during their teenage years and young adulthood.
The most significant risk factor is having von Hippel-Lindau disease. A family history of VHL disease substantially increases the chance of developing retinal capillary hemangiomas. When a tumor appears in both eyes or at multiple locations in one eye, the likelihood of an underlying VHL diagnosis is higher.
When adjusted for age at the time of diagnosis, the risk of VHL disease varied from 45% in young patients aged 10 years or younger down to 0.5% in patients between 61 and 70 years old (AAO). Genetic counseling and testing are recommended for patients presenting with retinal capillary hemangioma, particularly when the patient is young or the tumors are bilateral or multifocal.
Unlike many retinal conditions, retinal capillary hemangioma is not associated with common risk factors such as diabetes, high blood pressure, or smoking. The primary driver is genetic. Because VHL disease can also cause tumors in the kidneys, brain, spinal cord, and pancreas, a diagnosis of retinal capillary hemangioma often prompts a full-body evaluation for these related conditions.
Signs and Symptoms
In many cases, small retinal capillary hemangiomas produce no noticeable symptoms. They may be discovered during a routine dilated eye examination before the patient notices any change in vision. When symptoms do occur, they often include mild blurring of vision or subtle changes in the visual field.
As a tumor grows, it may leak fluid into and beneath the retina, causing more noticeable vision loss. Patients may experience a central blind spot called a scotoma, particularly if the tumor is located near the macula or optic disc. Floaters, which are small specks or lines drifting across the field of vision, may also develop.
Left untreated, retinal capillary hemangiomas can cause serious complications. These advanced warning signs require prompt attention from a retina specialist:
- Sudden increase in floaters or new flashes of light
- A shadow or curtain spreading across the vision
- Rapid or significant vision loss in one eye
- Distorted or wavy vision
These symptoms may indicate an exudative retinal detachment (when fluid collects under the retina and lifts it away), vitreous hemorrhage (bleeding into the gel-filled space inside the eye), or neovascular glaucoma (dangerously high eye pressure from abnormal blood vessel growth). If any of these symptoms appear suddenly, see a retina specialist or go to the emergency room immediately.
Diagnosis and Testing
A retina specialist will begin with a comprehensive dilated eye examination. By using special lenses and a bright light, the specialist can view the entire retina, including the far periphery where most retinal capillary hemangiomas develop. The characteristic appearance of a reddish-pink tumor with prominent feeder and draining vessels often allows a clinical diagnosis during this examination.
Several imaging techniques help confirm the diagnosis and guide treatment decisions. Fluorescein angiography involves injecting a fluorescent dye into a vein in the arm and then photographing the retina as the dye passes through its blood vessels. This test clearly outlines the tumor's blood supply and reveals any leakage.
Optical coherence tomography (OCT) uses light waves to create detailed cross-sectional images of the retina. OCT can detect fluid buildup, swelling, and structural changes caused by the tumor. OCT angiography, a newer noninvasive imaging method, has emerged as a valuable tool for detecting abnormal blood vessel patterns and monitoring how well treatment is working.
Because of the strong association with VHL disease, genetic testing for mutations in the VHL gene is recommended for most patients diagnosed with retinal capillary hemangioma. This is especially important for patients who are young, have tumors in both eyes, or have multiple tumors in one eye.
If VHL disease is confirmed, a full systemic evaluation is typically coordinated with other medical specialists. This may include brain and spinal cord MRI, abdominal imaging, hearing tests, and blood work to check for tumors in other organs.
Treatment Options
Very small, stable retinal capillary hemangiomas that are not leaking fluid or threatening vision may be monitored with regular examinations rather than treated immediately. A retina specialist will schedule follow-up visits to check for any growth or new leakage. This approach is most appropriate for tiny peripheral tumors that are not causing symptoms.
Argon laser photocoagulation (a thermal laser treatment that seals abnormal blood vessels) is one of the most commonly used treatments for retinal capillary hemangioma. It is particularly effective for peripheral tumors smaller than three disc diameters in size. During this outpatient procedure, the retina specialist directs focused laser energy at the tumor to destroy the abnormal vessels and reduce leakage.
Multiple treatment sessions may be needed to fully treat the tumor. Laser photocoagulation has a strong track record for peripheral lesions, though it may carry risks of scarring or damage to surrounding retinal tissue.
Cryotherapy (a freezing treatment applied to the outside wall of the eye) is another option for peripheral retinal capillary hemangiomas. A probe cooled to very low temperatures is placed against the sclera (the white outer coat of the eye) over the location of the tumor. The freezing destroys the abnormal tissue. Cryotherapy may be used alone or combined with laser treatment.
Because VEGF plays a central role in the growth and leakage of these tumors, intravitreal anti-VEGF injections (injections of medication directly into the eye) can help reduce fluid buildup and tumor activity. Avastin (bevacizumab), which is FDA-approved for cancer treatment and used off-label for eye conditions, has been used in managing retinal capillary hemangiomas.
Anti-VEGF injections are often used in combination with other treatments such as laser photocoagulation or photodynamic therapy (PDT), a treatment that uses a light-activated drug to target abnormal blood vessels. This combination approach has shown promising results, particularly for tumors located on or near the optic disc where laser alone may carry higher risk.
In advanced cases where retinal capillary hemangioma has caused tractional or exudative retinal detachment, surgery may be necessary. Pars plana vitrectomy (a surgery to remove the gel inside the eye) allows the retina specialist to address the detachment, remove scar tissue, and treat the tumor directly. This is typically reserved for cases where less invasive treatments have not been sufficient or complications have already developed.
Belzutifan, a hypoxia-inducible factor inhibitor, was approved by the FDA in August 2021 for adults with VHL disease who have associated renal cell carcinoma, central nervous system hemangioblastomas, or pancreatic neuroendocrine tumors not requiring immediate surgery. While not specifically approved for retinal hemangioblastomas, multiple case reports have demonstrated tumor regression and visual improvement in retinal lesions treated with belzutifan. This systemic medication represents a promising area of ongoing research for VHL-associated retinal tumors.
What to Expect
When detected and treated early, the outlook for retinal capillary hemangioma is generally favorable. In a study of 406 patients with VHL disease who had eye involvement, visual acuity was 20/20 or better in 84.5% of eyes with hemangioblastomas (NIH/PMC). However, 3% of patients in the study were legally blind, and 8.2% eventually required removal of one eye (NIH/PMC).
These numbers underscore the importance of early detection. Smaller tumors respond better to treatment than large or complicated ones. The location of the tumor also matters. Tumors near the optic disc or macula carry a higher risk of vision loss because treatment in those areas is more challenging.
Retinal capillary hemangioma requires lifelong monitoring. New tumors can develop over time, particularly in patients with VHL disease. A retina specialist will typically schedule regular dilated eye examinations, sometimes as often as every six months, to check for new growths or recurrence of treated tumors. Imaging studies including OCT and fluorescein angiography may be repeated periodically.
Recovery depends on the type of treatment performed. Laser photocoagulation and cryotherapy are outpatient procedures with relatively short recovery periods. Patients may experience mild discomfort, light sensitivity, or temporary blurring for a few days. After intravitreal injections, some soreness and mild redness at the injection site are common. Recovery from vitrectomy surgery takes longer, often several weeks, and may require special positioning instructions.
Living with Retinal Capillary Hemangioma
For patients with VHL disease or a family history of VHL, regular retinal screening should begin in childhood, typically by age 5 to 10, and continue throughout life. Because most new tumors develop before age 47, consistent follow-up during this period is critical. Even patients treated successfully for one tumor should continue regular examinations because additional tumors may form.
Because VHL disease can affect multiple organ systems, patients often work with a team that includes a retina specialist, neurologist, urologist, and genetic counselor. Coordinating care among these specialists helps ensure that all aspects of the disease are monitored and managed appropriately. Genetic counseling is also valuable for family members who may carry the VHL gene mutation.
Being diagnosed with a condition that requires lifelong monitoring can feel overwhelming, especially for young patients and their families. Understanding the condition, staying consistent with screening appointments, and communicating openly with the care team can help manage anxiety. Support groups and patient advocacy organizations for VHL disease offer resources and connections with others facing similar challenges.
When to See a Retina Specialist
Anyone who experiences sudden vision changes, new floaters, flashes of light, or a shadow across the vision should see a retina specialist or go to the emergency room immediately. These symptoms may indicate a complication such as retinal detachment or vitreous hemorrhage that requires urgent treatment.
Individuals with a known VHL gene mutation or a family history of VHL disease should have regular dilated eye examinations by a retina specialist, beginning in early childhood. Patients diagnosed with retinal capillary hemangioma who have not yet been tested for VHL disease should discuss genetic testing with their retina specialist. Early identification of VHL disease can lead to timely screening of other organs and better long-term outcomes.
Questions and Answers
Yes, if left untreated, retinal capillary hemangioma can lead to complications such as exudative retinal detachment, vitreous hemorrhage, and neovascular glaucoma, all of which can result in significant and sometimes irreversible vision loss. However, when these tumors are found early and treated promptly, many patients maintain good vision. Regular screening is the most effective way to catch tumors before they cause serious damage.
Not necessarily, but the possibility is significant. Research suggests that approximately 46% of patients with a single retinal capillary hemangioma may have VHL disease (AAO). The likelihood is higher in younger patients and lower in older patients. Genetic testing is recommended to determine whether a VHL gene mutation is present. Knowing this information is important because VHL disease can cause tumors in other parts of the body that also need monitoring.
Retina specialists generally recommend dilated eye examinations at least once or twice per year for patients with VHL disease. Screening often begins in early childhood, around age 5 to 10, and continues throughout life. The exact frequency may vary depending on whether tumors have already been found and how stable they appear. A retina specialist will create a personalized monitoring schedule based on each patient's situation.
Because retinal capillary hemangioma is primarily driven by genetic factors, particularly the VHL gene mutation, there are no known lifestyle modifications that can prevent these tumors from forming. The most important step is consistent, long-term screening so that any new tumors can be detected and treated at the earliest possible stage. Patients with VHL disease should also follow the screening recommendations for other organs that may be affected.
Belzutifan is FDA-approved for certain VHL-associated tumors in the kidneys, brain, spinal cord, and pancreas, but it is not specifically approved for retinal hemangioblastomas at this time. However, multiple case reports have documented tumor shrinkage and improved vision in retinal lesions when patients took belzutifan for their other VHL-related tumors. Research into its use for retinal capillary hemangioma is ongoing. Patients interested in this option should discuss it with both their retina specialist and the physician managing their VHL disease.