Sixty-one postmortem eyes were examined with clinical methods (slit lamp) and later sectioned for measurement of the liquid and gel vitreous. The amount of liquid vitreous was found to be progressively greater with increasing posterior vitreous detachment (PVD), and it was concluded that slit-lamp examination is a reliable method of evaluating the rheological state of the vitreous in the living eye. The total content of sodium hyaluronate (NaHA) in the vitreous was measured. Eyes proven to have no PVD had a higher concentration of NaHA than eyes with total PVD. Also, females had a lower concentration than males. There was no significant difference in NaHA concentration between the gel and liquid vitreous. The role played by different structural elements for the stability of the vitreous gel is discussed.