Polypoidal Choroidal Vasculopathy (PCV) is an eye condition characterized by abnormal blood vessel growth beneath the retina. This growth can lead to fluid or blood leakage, potentially causing vision impairment. Understanding available treatments for PCV is important for managing this condition and preserving vision.
What is PCV?
Polypoidal Choroidal Vasculopathy is a specific type of macular degeneration that affects the choroid, a layer of blood vessels supplying the retina. The condition is characterized by a branching network of blood vessels with distinctive polyp-like swellings at their ends. These polyps can resemble a “bunch of grapes” or a “string of pearls” when viewed with specialized imaging.
Individuals with PCV often experience symptoms such as blurred vision, distorted vision where straight lines appear wavy, or a blind spot in their central vision. In some instances, it can cause a sudden and severe loss of vision due to significant bleeding. Diagnosis of PCV involves a comprehensive eye examination and imaging techniques. Indocyanoma green angiography (ICGA) uses a special dye injected into a vein to highlight choroidal blood vessels, revealing branching networks and polyps. Optical coherence tomography (OCT) is also used to provide detailed cross-sectional images of the retina and choroid, identifying fluid accumulation and other abnormalities.
Established Treatment Options
Photodynamic Therapy (PDT)
Photodynamic therapy (PDT) is a two-step treatment to target abnormal blood vessels. First, a light-sensitive drug called verteporfin is administered intravenously. This drug travels through the bloodstream and selectively accumulates in the abnormal vessels of the choroid.
After the drug has circulated, a non-thermal laser is applied to the affected area. The laser activates the verteporfin, producing reactive oxygen species. These damage the abnormal endothelial cells lining the blood vessels, leading to their closure and preventing further leakage or bleeding. PDT can induce occlusion of the polypoidal lesions, which is an important goal in PCV treatment.
Anti-VEGF Injections
Anti-vascular endothelial growth factor (anti-VEGF) injections are a common treatment for PCV delivered directly into the eye (intravitreal injections). These medications work by blocking vascular endothelial growth factor (VEGF), a protein that promotes abnormal blood vessel growth and increases their permeability, leading to fluid leakage and bleeding. By inhibiting VEGF, these injections help to reduce fluid and blood under the retina.
Common anti-VEGF medications used in PCV treatment include bevacizumab (Avastin), ranibizumab (Lucentis), and aflibercept (Eylea). While anti-VEGF therapy can effectively reduce exudation and improve vision, its success in causing complete regression of the polypoidal lesions may be lower compared to treatments involving laser. Aflibercept may be particularly effective in cases with increased choroidal thickness.
Combination Therapy
Combination therapy for PCV uses both photodynamic therapy (PDT) and anti-VEGF injections. This approach combines the polyp-occluding effect of PDT with the anti-leakage effects of anti-VEGF agents, offering synergistic benefits. Combining PDT with anti-VEGF agents like ranibizumab or aflibercept can lead to better visual outcomes and higher rates of complete polyp regression compared to anti-VEGF monotherapy.
Combining these treatments can also reduce treatment burden by decreasing the number of anti-VEGF injections required. Combination therapy can result in significantly fewer injections compared to anti-VEGF monotherapy. This combined approach is often used for patients with PCV, as anti-VEGF inhibitors alone may be less effective in PCV than in other conditions like wet age-related macular degeneration.
Ongoing Care and What to Expect
Managing PCV is a long-term process, requiring regular follow-up appointments to monitor the condition and treatment effectiveness. These appointments involve eye examinations and imaging tests like OCT and ICGA to assess for any signs of disease activity, such as fluid leakage or recurrence of polyps. The frequency of these visits can vary, but regular monitoring is important because PCV is considered a chronic condition with a tendency for recurrence even after initial successful treatment.
Patients may require ongoing treatments, as the goal is to stabilize vision and prevent further loss, though some individuals may experience significant vision improvement. The need for continued injections or additional PDT sessions is determined by the disease activity observed during follow-up. While treatment can improve vision and prevent severe loss, the long-term course can be variable, and some patients may still experience irreversible scarring. Adherence to the prescribed treatment plan and attending all scheduled follow-up appointments are important for managing this condition effectively.