Susac Syndrome

Susac syndrome affects the small blood vessels of the retina, the inner ear, and the brain. It is understood as an immune-mediated endotheliopathy, where the immune system appears to injure the lining of those tiny vessels, involving cytotoxic T-cells and antibodies against endothelial cells that are thought to reduce blood flow to affected tissue. It is a rare disorder that predominantly affects young women.

A 2025 systematic review pooling 435 published cases found a median age at diagnosis of 35 years, with neurological symptoms present in about 87 percent of cases, hearing loss common among those with ear involvement, and retinal artery blockages common among those with eye findings, though the full triad of all three was present at onset in only around 1 in 5 people, which can delay diagnosis. It needs prompt specialist care.

Common signs

Visual disturbances or partial vision loss from blocked retinal vessels, hearing loss, ringing in the ears, vertigo, and brain-related changes such as headache, confusion, memory problems, and mood changes.

This is a plain-language summary for orientation, not a diagnosis. Mechanisms are described as current understanding, not settled fact. Work with your own clinician for your care.