Peer navigation

The Atlas guide

The atlas is designed to allow the user to interactively study the anatomically labelled images of the heart. In this brief guide, we aim to explain the changes we have made since our previous atlas, introduce new features and explain our new navigation method for selecting an image to view. The important changes to the atlas are how the user can select a new Image Plane or image series how they navigate through those images.

The Atlas is broken up into two main Panels:

The Main Panel
This panel displays the labelled image, this panel has features that allow you to zoom in and pan around the image.
The Navigation Panel
This is a new feature and allows the user to preview the next images before loading and changing the labelled image in the main panel. The atlas's control features contains features for manipulating the appearance of the image in the main panel including, zoom, Brightness/Contrast, Toggling Labels on/off, resetting the conditions, and also for selecting a different image quality and how to select a new image plane or series.

The Main Panel

Zoom

A close-up of the main panel.

Zooming in and out of the image in the previous altas was achieved by, holding down the clicking and dragging the mouse up or down the image to zoom in and out respectively. The new atlas now has an additional zoom slider to indicate the current magnification of the visible image allowing the user to record and set a desired zoom factor.

The zoom tool is designed for focusing down on individual objects of interest in the image and it has a maximum magnification of 300%. You will note that as other objects leave and enter the field of view their corresponding label will also disappear and reappear like in the previous atlas, the user can then pan (int link) around the image to investigate the region of interest.

Tip

For optimum image resolution at high magnification we suggest to select a higher image quality.

Pan

In the previous atlas it was only possible to pan around the image, by holding down the shift key, clicking and holding the left mouse button and dragging the mouse cursor over the image. The new atlas has been extended to include a more traditional and intuitive means to pan around the image through the use of the vertical and horizontal scrollbars. However before the scrollbars are activated the user must zoom into the image.

The Pan tool enables the tracking of objects of interest around the image, as the objects leave and enter the visible area the, object labels disappear and reappear as in the previous atlas.

A close-up of the navigation panel.

Cycling through the images in a series

An exciting feature of our new atlas is the incorporation a navigation panel that enables a user to preview the next image in the plane. The navigation panel consists of two frames, the preview frame and the slice position frame. The preview frame is used to view a new image before it is loaded into the main panel. While the slice position frame shows an image perpendicular to the current plane and overlaid on top of it is the intersection of the image slices in that series. The current image in the preview frame is shown in a darker yellow.

The user can subsequently select the appropriate image in the series to view with the scrollbar beneath the slice position. Dragging or clicking the scroll bar will allow the user to cycle through the other images in the series in order, previewing them and their position without changing the main image. The main image will update after the scrollbar is released. The user can also click on the "next" and "prev" labels to cycle through the images similar to the arrows on the scrollbar.

Additionally we would like to note that when cycling through the different images the atlas maintains the current zoom factor and panning co-ordinates to allow the user to investigate the same region of interest through the slice. Also the two image frames apply the same brightness and contrast settings of the main panel.


Control features

Selecting the Image Series

The final addition in the new atlas is the choice of image plane. To improve speed we have incorporated the selection of image plane into the Atlas rather than as a separate web page. To change image plane the user can select the plane from the drop down box named "Image Plane." The atlas will subsequently load the new image plane starting with image number 1.

Note: Whilst loading the new Plane, the atlas is not respondent to the user and the atlas is initialised with the long axis image series.

Detail of the Image Viewer button panel.

Brightness and contrast

Brightness and Contrast sliders in the new atlas have replaced scroll bars of the original atlas. They work the same way and the user can vary them by clicking and dragging the marker, adjusting the image to match their light conditions, monitors and personal preferences for optimal viewing of the image.

Tip

the value associated with the zoom and brightness is arbitrary, it instead is intended as reference for the user when returning to the atlas.

Toggling Labels on and off

The user can control whether or not to display the labels by the drop down box "Labels." There is three settings, on/off/markers. The "markers" setting only displays the position of the label on the image.

Tip

This is a useful feature for testing your ability to locate anatomical features.

Reset

The Reset button returns the contrast, brightness and Zoom settings to their default values.

Selecting the Image Quality

With the variation in Internet speeds today, the new atlas incorporates three different image resolutions for the main image.

Low
Select this resolution for a 256 x 256 Jpeg image that maintains a 75% image quality. Typical Image size 34K
Med
Select this resolution for a 256 x 256 Jpeg image that maintains the full 100% image quality. Typical Image Size 40K
High
Select this resolution for a 512 x 512 Jpeg image that maintains the full 100% quality. Typical Image Size 80K

The three different settings allow a user to choose an appropriate setting to match their download speed. It is suggested for dial-up connections to use the default, low, setting and broadband connections to use either Med or High setting. Which can be set with the drop down box named "Image Quality" Improvement with the high resolution image is most prominent when the user zooms in on a region of interest.

Note: Whilst loading the Image of a new resolution, the atlas is not respondent to the user.

Conclusion

This completes our Atlas guide, in the lower right corner of the atlas you will find the help button.

Clicking this will return you to this page, it may helpful to have this page open in another window to refer to while getting used to the new atlas.