Telemedicine refers to the use of networked computers to perform health care tasks, like diagnosis, therapy and follow-up. Medical images represent the essential information exchanged by telemedicine systems and are characterized by specific requirements concerning acquisition, storage, transmission and analysis modalities. In the telemedicine systems, medical image communication is performed over Transmission-Control Protocols (TCP). Real-time protocols for ATM-based multimedia networks are under study. We propose a new system for medical image communication where the physician is enabled to browse remote medical images, at high-resolution and in real-time. This system has two innovative features: a better organization of the image data for a fast access to the high-resolution images (hierarchical database) and the integration of synchronization mechanism at the visualization level of the application (requirements, specification and implementation). This document addresses a method to facilitate the design of a synchronization mechanism for telemedicine applications: with this method, a Time Petri Net model of the system is obtained and the end-to-end synchronization requirements are transformed in component specific parameters. In a second phase, the Petri Net model is used to design the synchronization mechanism and to guarantee that synchronization requirements are fulfilled at run-time, monitoring and modifying the state of the system, according to the resource usage and the specified behavior. Keywords: telemedicine, synchronization, Petri Nets.