To lnvestigate the change of serum collagen IV (CIV) level in patients with diabetic retinopathy (DR)

We measured the serum CIV concentration in 89 NIDDM(30patients with DR were included)and 54 normal controls. Moreover

we studied the relationship between serum IV level and severity of IDR. The results showed that serum IV level of diabetic patients was higher than that of normal controls

and was higher in patients with DR than that in patients without DR. The IV level was significantly correlated with the severity of DR

and it increased in patients with proliferative DR as compared with patients with background DR. lt suggests that the increase of serum IV level is significantly related to the presence and development of DR

and the determ ination of Serum CIV concentration maybe a convenient and helpful index in monitoring the activity of DR in NIDDM.