Synchronization

Prism can lock display and navigation so multiple viewports stay aligned. Turn sync on when you compare the same region in two or more series, or when MPR panes should move together. Turn it off when you want independent navigation, such as different zoom in each pane.

What you can lock

VOI sync links window and level so contrast and brightness match. Pan and zoom sync links spatial position and magnification. Slice sync links index along the stack so scrolling one pane steps the other. Toolbar toggles expose each kind. Icons vary by theme. The three locks stay the same.

When each helps

Comparing reconstructions with different default windows often starts with VOI off while you explore, then on once you want matching density. Chest CT with nodule versus mediastinal windows often wants VOI off on purpose so two different windows can sit side by side. When two CTs open with technologist-chosen defaults that do not match, enable VOI sync and nudge one pane until both look honest.

Pan and zoom sync helps for prior versus current of the same body part, or two phases with similar slice thickness. If pixel spacing or FOV differ a lot, linked pan can look wrong. Disable one pane, align by hand, then re-enable if it helps.

Slice sync is for two stacks with similar spacing along the same axis, and for many MPR layouts where thickness should stay in step. Disable it when you want an offset, such as comparing lesions at different vertebral levels.

Layout quirks

Entering an MPR preset may auto-enable some sync kinds. You can still override. Fullscreen still applies sync to other non-fullscreen viewports. Exit fullscreen to see the cross-pane effect clearly.

Choose a grid that supports the comparison you need, then set VOI before or during sync rather than fighting both problems at once.