Abstract: A medical collaboration system for pre-operative collaborative assessment includes an imaging center, a data center, a DICOM storage, at least one displaying means, an API and a rendering device. The data center includes a cloud storage, a user database, a DICOM converter and a web interface; the cloud storage includes a 3D medical volume storage; the imaging center is connected to the data center. The API is connected to the data center, the at least one displaying means, the rendering device and the 3D medical volume storage. The DICOM storage is connected to the DICOM converter and the DICOM storage is configured to send the 2D medical records to the DICOM converter. The DICOM converter is configured to remove confidential metadata from the 2D medical records, convert the 2D medical records into 3D medical volumes, and send the 3D medical volumes to the 3D medical volume storage for storing.