A Novel Connection: Understanding Polypoidal Choroidal Vasculopathy in Usher Syndrome Type 2
Usher syndrome is a complex genetic disorder that affects both vision and hearing, often presenting as retinitis pigmentosa (RP) alongside sensorineural hearing loss and sometimes balance issues. For individuals and families navigating the challenges of Usher syndrome, understanding every facet of the condition is crucial. A recent case report published in BMC Ophthalmology in 2026 sheds new light on a previously unobserved complication in Usher syndrome type 2: polypoidal choroidal vasculopathy (PCV).
This discovery is particularly significant because it challenges long-held assumptions about eye conditions often seen in Usher syndrome patients. RP typically involves a thinning of the choroid, the vascular layer beneath the retina. PCV, on the other hand, is usually associated with a thickened choroid, or at least not a thinned one. This case report highlights that even with choroidal thinning, PCV can occur, urging clinicians and researchers to consider this possibility in Usher syndrome patients experiencing new visual disturbances.
Unveiling a Rare Complication: The Case Study
The report details the case of a 63-year-old man diagnosed with Usher syndrome type 2, confirmed by the presence of two pathogenic variants in the USH2A gene. He had experienced night blindness, a common symptom of RP, and also suffered from moderate sensorineural hearing loss. Six years after his initial Usher syndrome diagnosis, he noticed a significant decline in vision in his left eye. His best-corrected visual acuity (BCVA) dropped to 20/80, indicating a substantial impairment.
To investigate the cause of this sudden visual decline, a comprehensive set of advanced imaging techniques was employed. These included spectral-domain optical coherence tomography (SD-OCT), fluorescein angiography, indocyanine green angiography, and swept-source optical coherence tomography angiography. These sophisticated tools allowed the medical team to peer into the intricate layers of the retina and choroid, revealing the presence of PCV. PCV is characterized by abnormal, branching blood vessel networks and distinctive