梯度矢量流测地线活动轮廓模型作为对测地线活动轮廓模型的重要改进，不仅扩大了测地线活动轮廓模型的适用范围，而且改进了它的分割效果。但由于该模型中推动活动轮廓演化的外部力量来自于梯度矢量流，因此活动轮廓在演化过程中可能会由于弱边缘等因素的影响而陷于不希望的局部最小值。为尽量减少弱边缘对活动轮廓初始位置的限制及其对轮廓演化的不利影响，提出了一种新的辅以区域力量的梯度矢量流测地线活动轮廓模型，该模型首先将基于区域信息的力场与梯度矢量流力场相耦合，然后由以上两种力量构成的耦合力场，使活动轮廓模型能够有效地克服弱边缘的影响而收敛到所期望的边缘。实验结果表明，辅以区域力量的梯度矢量流测地线活动轮廓模型与梯度矢量流测地线活动轮廓模型相比，不仅可以更灵活地设置初始轮廓的位置，而且对弱边缘的干扰也有较好的适应性，并能有效地避免边缘泄漏。

As an important improvement of geodesic active contour model, gradient vector flow geodesic active contour model enlarged the applicability of geodesic active contour and improved its segmentation effect. Because the external force driving the evolution of active contour derived from gradient vector flow, active contour may be trapped into undesired local minimum due to some reasons, such as weak edges. In order to decrease the limitation of active contour’s initial location and the negative influence of weak edges on the evolution of active contour, we proposed a new gradient vector flow geodesic active contour model aided region force. This model combined external force field based on region information with gradient vector flow force field. This coupling external force field enables geodesic active contour to overcome the influence of weak edges and converge desired boundary. Experimental results show that gradient vector flow geodesic active contour model aided region force has more flexibility to determine the initial contour，better adaptability to the disturbance of weak edges and can effectively avoid boundary leakage compared with gradient vector flow geodesic active contour model.