Based　on　the　local　image　information,　we　propose　a　new　improved　local　active　contour　model　to　segment　inhomogeneous　images.　The　level　set　evolution　equation　of　the　proposed　model　which　is　different　from　improved　Chan-Vese　(ICV)　model　and　local　Chan-Vese　(LCV)　model　is　ordinary　differential　equation.　Without　mean　curvature　and　other　complicate　difference　items,　the　implementation　becomes　simpler　by　employing　a　finite　difference　scheme,　thus　the　efficiency　of　global　segmentation　is　dramatically　improved.　Experimental　results　on　synthetic　images　as　well　as　real　medical　images　are　shown　in　the　paper　to　demonstrate　the　segmentation　accuracy,　efficiency　and　robustness　of　the　proposed　method.