Table 5.

Algorithms for the assessment of vessel tortuosity.

Authors	Method	Database(s) used	No. of images	Performance (SCC)
Grisan et al. [73]	Inflection-based measurement	RET-TORT [73]	60	0.949 (artery), 0.853 (vein)
Poletti et al. [75]	Combination of measures	Non-public dataset	20	0.95
Oloumi et al. [76]	Angle-variation-based measurement	Non-public dataset	7	NA
Trucco et el. [79]	Curvature and vessel width-based measurement	DRIVE	20	NA
Aghamohamadian-Sharbaf et al. [80]	Curvature-based measurement	RET-TORT	60	0.94