With the rapid development of science and technology and the improving medical service, medical image's role in clinical diagnosis and treatment becomes increasingly prominent. It has become a high-profile task to help the doctors pick out desired targets from massive medical images. Currently, techniques of text-based medical image retrieval have failed to meet the need of massive medical image retrieval. On the other hand, techniques of content-based medical image retrieval are already established and hold vast research potential. Starting with the introduction of matured techniques of medical image retrieval, the paper expounds on the evaluation criteria of the effectiveness of such techniques, then on the modified text-and-content-based medical image retrieval algorithm. The last part is the verification of the research conclusion with contrast experiments illustrated by the sample figures.