Fuchs Endothelial Dystrophy

What happens in Fuchs dystrophy

The endothelium is a mosaic of cells lining the inner cornea that never regenerate. In Fuchs dystrophy they are lost faster than in normal aging, and small bumps called guttae form on the membrane beneath them. While enough cells remain the cornea stays clear. Below a threshold, fluid accumulates, the cornea thickens and hazes, and in advanced disease the surface blisters. Overnight, with the eyes closed, evaporation stops and swelling is greatest, which is why vision is worst in the morning.

Stages and symptoms

• Early: guttae visible at the slit lamp, no symptoms; often found at a routine exam
• Moderate: glare and halos from the guttae, morning blur that clears, gradual loss of contrast
• Advanced: persistent blur all day, corneal thickening measurable on pachymetry, reduced vision
• Late: surface blisters that cause pain and recurrent erosions, and scarring

Monitoring

Specular microscopy images and counts the endothelial cells, and pachymetry measures corneal thickness. Together they track progression over years and identify the point at which the cornea is decompensating. Most patients are examined annually, more often as disease advances.

Treatment

Early and moderate disease is managed with hypertonic saline drops or ointment, which draw fluid from the cornea and improve morning vision, and with a hair dryer held at arm's length in the morning to speed clearing. When vision declines despite this, the failed layer is replaced. DMEK, Descemet membrane endothelial keratoplasty, transplants a single cell layer through a small incision, with rapid visual recovery and a low rejection rate; it has largely replaced older full thickness transplants for Fuchs. DSAEK is a slightly thicker graft used in some eyes. Dr. Youssefzadeh personally performs corneal transplant surgery. He evaluates whether a transplant is appropriate and discusses the options with you.

Fuchs dystrophy and cataract surgery

Cataract surgery stresses the endothelium, and a cornea with Fuchs dystrophy may decompensate afterward. Cell counts and thickness before surgery guide the plan: in mild disease, gentle surgery with endothelium-protective techniques; in moderate disease, cataract surgery combined with DMEK, or DMEK first, may be considered. Lens choice also matters, since a swollen cornea degrades multifocal optics. This is one of the most common reasons a cataract patient is referred to a cornea specialist, and it is planned carefully here.