Expert System for Risk Analysis in Sight-threatening

 Diabetic Retinopathy using MatSOAP

Control of glucose, BP and cholesterol can slow progression of sight threatening  retinopathy (STDR).  Here we define the retinopathy as as moderate pre-proliferative retinopathy or greater and/or ciricinate maculopathy or exudates within one disc diameter of centre of the fovea), ungradeable images or other significant eye disease in either eye and consequently attending for slit-lamp biomicroscopy.


The Expert System for Risk Analysis in Sight-threatening Diabetic Retinopathy is constructed from 500 patient records selected arbitrarily from the St Paul's Eye Unit Diabetic Database. The likelihood (or 'risk') of developing STDR is estimated using a simple generalized linear network (GLM) from a combination of risk factors viz:

Gyclosylated hemoglobin, HbA1c [%]

Diastolic blood pressure [mmHg]

Systolic blood pressure [mmHg]

Total random cholesterol [mg%]

Duration of diabetes prior to onset of STDR [years]

Two webpages are available:

Basic: estimate the risk from any combination of 5 values of risk factors returning:

            1. risk [%]

            2. confidence limits [95%] of  risk [%]

            3. AUROC: area under the receiver-operator-curve: values above ~0.7 are good; below should be treated cautiously

Advanced: profile of any risk factor with-respect-to any other combination of the remaining 4 risk factors.

The Expert System is written in MatLab using MatSOAP technology. Other eye-related web-based applications are at www.liverpooleye.org.


For technical details, contact Tony Fisher at a.c.fisher@liv.ac.uk