Getting started
Opening DICOM files
DN Viewer reads DICOM files directly from your disk — no conversion needed. You can open a folder, a ZIP archive, or your cloud-uploaded studies. All methods are accessible from the Open button in the top toolbar (or click the small caret ▾ beside it for more options).
Open a local folder
A left-click opens a system folder picker. Navigate to the folder that contains your DICOM files and click Open. DN Viewer will load all DICOM instances it finds in that folder and its subfolders.
Right-click the Open button (or click the ▾ caret), then choose Add Folder to workspace. The new folder's studies are added alongside whatever is already loaded.
Open a ZIP archive
DICOM studies shared as ZIP files (common from hospitals and teleradiology platforms) can be opened directly from the toolbar without manual extraction.
Select your .zip file. DN Viewer extracts it to a temporary folder and loads the studies immediately.
Choose Add ZIP to workspace from the same dropdown. Existing studies remain open.
Open cloud-uploaded studies
If your studies are backed up to the DN Viewer cloud, you can browse and download them directly from inside the app:
Click Sign in in the top-right corner of the toolbar and complete authentication. An organization account is required for cloud study access.
The cloud study browser opens. Select a study and click download — it loads directly into the viewer.
Export a study as ZIP
With a study loaded, click Open ▾ → Export ZIP, choose the study from the submenu, and pick a save location. DN Viewer packages all DICOM instances into a standard ZIP archive.
Network access
Connecting to a PACS or DICOM server
DN Viewer includes a built-in C-FIND client that lets you query any DICOM server (PACS, modality, or worklist) on your network and retrieve studies directly into the viewer.
Open the PACS search panel
Three ways to open the Search PACS panel:
- Click the Search PACS button in the toolbar (blue, left side).
- Press Q from anywhere in the app (when no text field is focused).
- The panel also opens automatically when the workspace is empty.
Configure your DICOM server
In the C-FIND panel, locate the server configuration section. Enter your PACS hostname or IP address, DICOM port (default 104), and the called/calling AE titles for your site.
Use the Echo / Verify button to confirm DN Viewer can reach your server (C-ECHO). A success response confirms the AE titles and network path are correct.
Enter patient name, ID, date range, or modality in the search fields and press Search. Select a study from the results list and click Retrieve to download it into the viewer.
Keyboard reference
Keyboard shortcuts
All shortcuts are active when no text input is focused. Tab cycles through the most common tools; number keys apply window/level presets instantly.
Global shortcuts
| Key | Action |
|---|---|
| Tab | Cycle primary tool — steps through Scroll → Length → HU Probe → Angle → Cobb Angle → Scroll. If more than 3 s pass between presses the cycle resets to Scroll. |
| Q | Open Search PACS — opens the C-FIND / PACS search panel. |
| Shift | Toggle Series Preview — shows or hides the series thumbnail strip. Detected on key-press edge (hold not required). |
| Esc | Radial tool menu — opens the circular quick-access menu centred on the screen. Press again or click outside to close. |
| F1 / F2 | Pane actions — handled per-pane (flip / rotate image in the currently hovered pane). |
Window / level preset keys
Press the number keys 1–5 to instantly apply a tissue-specific window preset to the active pane.
Speech-to-text shortcut (report pane)
| Key | Action |
|---|---|
| Alt hold | Start recording — hold Alt while the report pane is open to begin speech-to-text dictation. The mic button turns red. |
| Alt release | Stop & process — release Alt to stop recording. The button pulses orange while the server transcribes your dictation. The result is inserted into the report. |
Tools reference
Measurement & annotation tools
All tools are accessible from the Measure dropdown in the toolbar or via the Radial menu (Esc). Press Tab to quickly cycle the most-used ones.
Click two points to draw a distance measurement. Result shown in mm. Shortcut: Tab to cycle here.
Click to draw two lines meeting at a vertex. The included angle is displayed in degrees.
Four-click tool: place two endplate lines. DN Viewer calculates the Cobb angle between them for spine assessment.
Click-drag to draw an elliptical region of interest. Mean, min, max HU and area are shown in the overlay.
Places a circular sampling ROI. Adjust the radius (0 – 60 px) in the tool strip below the toolbar. Sync position across panes of the same study with the Sync toggle.
Left-click for positive prompts, right-click for negative prompts. AI segments the region and reports its area. Available with the AI segmentation feature.
Click to place horizontal level markers on MRI slices for spine-level labelling. Clear all markers with the Clear Lines button in the tool strip.
Click-drag horizontally to adjust window width; vertically for level. Or use keys 1–5 for instant presets.
Click-drag to zoom in and out. Also accessible from Image Tools in the toolbar.
Click-drag to pan the image. Tip: hold left + right mouse button and drag to pan from any tool mode.
Click-drag horizontally to rotate the image in-plane.
Opens a basic clinical calculator. Found under Measure → Calculator.
HU Probe options
When HU Probe is active, a secondary strip appears below the main toolbar with two controls:
- Radius slider (0 – 60 px) — drag to resize the sampling circle. 0 = single-voxel point probe.
- Sync ON / OFF — when Sync is on, placing the probe in one pane automatically mirrors its position to all other panes showing the same study.
Window & level
Window / level presets
Presets apply a clinically standardised centre + width combination to the active pane. There are three ways to apply them:
- Press number keys 1–5 (fastest).
- Click the ▾ caret next to the Window button in the toolbar.
- Open the Radial menu (Esc), hover over the Window button, and the preset panel slides out.
AI features
AI reporting & speech-to-text dictation
DN Viewer includes an AI-assisted report writer and hold-to-speak speech-to-text dictation. Both require signing in and an active subscription.
Open the report pane
Click the Sign in button (top-right of the toolbar). After authentication the button shows your email in green.
The report side pane opens on the right of the viewer. The pane button is highlighted in blue while active.
Dictate into the report with speech-to-text
With the report pane open, the mic button appears in the toolbar. See STT keyboard shortcut above for the full visual state reference. In brief:
- Hold Alt to start recording (mic turns red).
- Release Alt to stop — the mic pulses orange while the server transcribes.
- Transcription is inserted into the open report automatically.
AI Chat assistant
Click Chat in the toolbar to open the AI assistant panel — powered by radiologyassistant.ai. Ask clinical questions, request differential suggestions, or get help drafting report language without leaving the viewer.
Viewer layout
Layouts, panes & views
Adjusting the number of panes
The Layout control in the toolbar lets you split the viewer into 1–8 simultaneous panes. Hover over the pane count or the ▾ caret beside it to reveal a slider and manual input field. Click the red ✕ to reset to a single pane instantly.
Saving and loading layouts
Set the pane count and load each pane with the series you want.
Give the layout a name. It is stored locally and appears in the ▾ dropdown beside Save.
Click the ▾ caret beside Save → select the layout name. For MRI: DN Viewer remembers which layout you used per study and reopens it automatically next time you load that study.
MPR and 3D views
Switch the active pane between views from the Radial menu (Esc) outer ring:
- MPR — three-plane reformatted view (axial / coronal / sagittal). Toggle the MPR crosshair/axes overlay with the Axes button in the toolbar.
- 3D — GPU-accelerated volume raycast. Toggle the same button to return to axial view.
Axes / crosshair toggle
The Axes button in the toolbar (green when active) shows or hides the MPR crosshair overlay. Useful when you want a clean view for screenshots.
Image tools
The Image Tools dropdown (toolbar) groups several utility actions:
- Overlay / Fusion — pick two series to overlay. Click the same series twice to fuse it with itself (useful for comparing window settings).
- Print Images — layout US series frames in a configurable grid and send to a printer.
- View DICOM Metadata — inspect all DICOM tags for the current study's first instance.