Dr Ben Wild
Overview |
For light to stimulate the retina (the part of the eye that detects light), it must pass through a clear cornea (front of the eye), the pupil (the hole in the colored part of the eye also known as the iris), the clear lens inside the eye and through clear gel called the vitreous humor. The vitreous humor is a gel composed of collagen, proteins, hyaluronic acid and water and acts as scaffolding for the eye, helps transfer nutrients to the different structures within the eye and helps keep the eye inflated.
Sagittal view of a healthy eye.
Asteroid hyalosis is a degenerative process that occurs when calcium pyrophosphate salt particles accumulate in the vitreous humor. About 3% of people over the age of 75 have some sign of asteroid hyalosis. In the vast majority (75% of cases) this occurs unilaterally (in one eye). It is still uncertain what the origin of these salt crystals are or why it occurs.
Sagittal view of an eye with crystals, signifying asteroid hyalosis, floating in the vitreous gel.
Signs and Symptoms |
Signs
Off white to yellow crystals suspended in or floating within the vitreous humor.
Symptoms
Usually no symptoms, sometimes patients see many small floaters in their vision.
Causes and Risk Factors |
Causes
Still unknown.
Risk Factors
Male gender.
Prevention and Treatment |
Prevention
There are no known preventative measures.
Treatments
· Vitrectomy (surgical removal of vitreous humor).
Prognosis |
Asteroid hyalosis is not known to be associated with any other health conditions or cause damage to the eyes. It is very rare that enough crystals accumulate to affect vision but if that does occur, vitrectomy surgery can clean out the vitreous humor.
Comments