Abstract
Purpose :
The vitreous humor (known as "the vitreous") is a transparent, gel-like fluid that fills the ocular cavity between the lens and the retina. To date, the biochemical composition of the living human vitreous has only been approximated from animal models or from human post-mortem biochemistry. The generalizability of these data to the human situation in vivo is unclear.
Methods :
We measured the concentration of sodium, potassium, chloride, calcium, magnesium, glucose, lactate, beta-hydroxybutyrate, copper, zinc, selenium, iron, ferritin and transferrin and the osmolality in 27 individuals, with a clinically normal vitreous, scheduled for retinal surgery. Perioperative serum samples were also obtained for comparison.
Results :
The vitreous humor extracted from living humans has a markedly different composition to commonly reported reference values obtained from animal studies. The vitreous biochemistry was similar in males and females. There were significant differences in magnesium, glucose, lactate, copper, iron and transferrin concentrations between diabetics and non-diabetics.
Conclusions :
The current data have important applications: (1) they provide hitherto unavailable information for forensic pathology, particularly estimation of plasma glucose concentration at the time of death; (2) they provide a foundation for the development of more physiological intraocular irrigating solutions for vitreoretinal surgery; (3) they provide validation for vitreous solute measurements obtained from emerging non-invasive imaging technology.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.