The term “eye polyp” is an informal phrase often used to describe Polypoidal Choroidal Vasculopathy (PCV). PCV is a complex eye condition involving abnormal blood vessels in the choroid, a vascular layer beneath the retina. These vessels can leak fluid or blood, potentially damaging the retina and impairing vision.
Understanding Polypoidal Choroidal Vasculopathy
PCV is characterized by abnormal, branching vascular networks in the choroid, often with “polyp-like” dilations at their ends. These vessels can leak fluid or blood, damaging the overlying retina and potentially causing vision impairment.
The exact causes of PCV are not fully understood, but it involves abnormally shaped vessels within the choroid. The disease can lead to fluid and blood leakage, and in some cases, the formation of large vascular channels and polypoid formations. While PCV shares clinical features with wet age-related macular degeneration (AMD), such as abnormal vessel growth and subretinal leakage, it is considered a distinct subtype. PCV often presents with pigment epithelial detachments (PEDs) and exudative changes, which can progress to subretinal fibrosis.
Recognizing Symptoms and Risk Factors
Individuals with PCV may experience symptoms affecting their central vision. Common complaints include blurred or dim vision, distorted vision (where straight lines appear wavy), floaters, or blind spots. A sudden, sometimes severe, decrease in vision can occur due to significant bleeding. Symptoms appear abruptly. Eye care professionals may detect abnormal vessel growth during routine eye examinations, highlighting the importance of regular check-ups.
PCV tends to affect individuals over the age of 60, though it can occur in younger adults. There is a notable demographic predisposition, with the condition being more prevalent in Asian and African populations compared to Caucasians. While the precise causes remain elusive, risk factors associated with PCV include male gender, a history of cigarette smoking, and hypertension. Some studies also suggest a link to higher body mass index and education levels. Genetic predispositions may also play a role in the development of PCV.
Diagnosing and Treating PCV
Diagnosing PCV involves a thorough eye examination by a retina specialist and specialized imaging tests. Optical Coherence Tomography (OCT) is routinely used to identify PCV by detecting fluid accumulation and structural changes within the retina and choroid. OCT can reveal characteristic features such as sharp-peaked pigment epithelial detachments (PEDs), thumb-like projections, and subretinal pigment epithelium (RPE) ring-like lesions. These findings help differentiate PCV from other conditions like neovascular age-related macular degeneration (nAMD).
Another diagnostic tool is fluorescein angiography (FA), where a dye injected into a vein allows for visualization of blood vessel leakage in the retina. On FA, PCV lesions can resemble occult choroidal neovascular membrane lesions, which might be mistaken for AMD if not further evaluated. However, indocyanine green angiography (ICGA) is considered the definitive test for PCV. ICGA involves injecting a different dye that better highlights the choroidal vasculature, allowing for clear visualization of the characteristic branching vascular networks and polyp-like dilations. The polyps appear as focal hyperfluorescent spots on ICGA, which is crucial for confirming the diagnosis.
Treatment for PCV primarily aims to preserve vision and prevent further loss, with common approaches including photodynamic therapy (PDT) and anti-VEGF injections. Photodynamic therapy involves injecting a light-sensitive drug, verteporfin, into the bloodstream, which is then activated by a non-thermal laser light directed at the abnormal vessels. This process helps to close off the leaking polyps and abnormal blood vessels. PDT is widely recognized for its effectiveness in inducing the regression of these polyp-like dilations.
Anti-VEGF (vascular endothelial growth factor) injections are another common treatment. Medications like ranibizumab (Lucentis), aflibercept (Eylea), or bevacizumab (Avastin) are injected directly into the eye. These drugs work by blocking VEGF activity, a molecule that promotes abnormal blood vessel growth and leakage, thereby reducing fluid leakage and abnormal vessel growth. While anti-VEGF therapy is effective in managing the fluid and bleeding associated with PCV, its success in completely resolving the polypoidal lesions can vary.
Combination therapy, utilizing both PDT and anti-VEGF injections, is frequently employed and has shown favorable outcomes. In some severe cases, less common treatments such as thermal laser photocoagulation or vitrectomy surgery may be considered. Early diagnosis and treatment are important, as they can help restore vision or prevent further vision loss in many patients.