摘要： Tumor segmentation from magnetic resonance images (MRI) is an error-prone and time-absorbing process. Recently, optical methods have opened a new avenue to tack with the aforementioned problem. In this paper, we propose a novel architecture adapting the Optical Scanning Holography (OSH) to the detection of the abnormal tissue regions in MRI. The proposed method combines an o?-axis optical scan, performed by a heterodyne fringe pattern, and a MR image display ensured by a spatial light modulator. The output in-phase component of the scanned current is collected digitally. Hence, a high-precision distribution of biological tissues is extracted using this in-phase component. Its maximum position is exactly the one of the tumor. Meanwhile, this position is used in an Active Contour Model (ACM) to perform a fast segmentation of the extent corresponding to the tumors. Several images of brain tumors from BRATS database, with tumors having di?erent contrast and form, are used to test the proposed system. Parameters reverted by the optical process are used to investigate the detection performance. Further, in terms of tumor segmentation, the proposed OSH-ACM process has high performance metrics compared to some of recently published method. The underlying physics of the precision superiority, presented by the OSH-ACM, is the high-precision extraction of the abnormal tissue regions by the in-phase component of the scanned current.