Optic Disc and Optic Cup Segmentation Methodologies for Glaucoma Image Detection: A Survey

Table 1

Performance metrics for optic disc and optic cup segmentation.

Measurement	Description
Optic disc overlap	TP/TP + FN + FP
CDR error	CDR (GR) − CDR (PRP)
ISNT rule	Optic disc-optic cup (obtain the thickness in all the four quadrants)
Specificity (SP)	TN/TN + FP
Sensitivity (SN)	TP/TP + FN
Accuracy (Acc)	TP + TN/TP + FP + FN + TN
Positive predictive; accuracy (PPA)	TP/TP + FP
Dice metric (DM)	2 TP/FP + TP + FN
Relative area difference (RAD)	FP + FN/GT