Image Viewer > Basic Viewing > Hanging Protocols

This section contains solutions to common problems you may encounter while using Hanging Protocols as well as some general recommendations.

Recommendations

Avoid manually editing Protocol/Layout properties, and use the Basic method (e.g. capturing Layouts) of creating and modifying Hanging Protocols as much as possible. When you capture the state of the viewer, the HP Designer tries to figure out the layout instructions to put into the protocol, including the contents of the image boxes (display sets, prior studies), right down to the Window/Level and orientation of the images. This is the simplest and most powerful way to maintain your Hanging Protocols.

2.	Standardize your acquisition methods (see Common Problems below). No matter how powerful a Hanging Protocols implementation is, it can only work really well when similar studies are acquired in a repeatable manner.

3.	Create new Layouts, not new Protocols. Because every patient has a different history, you may be inclined to create many Protocols like in the screen below where you have a different Protocol for different patient history scenarios:

This is not recommended because using this method, the Workstation is not going to be able to figure out which one to apply, and you'll end up having to inspect the patient's history and apply a Protocol manually. Instead, create one Protocol for a particular kind of study based on Modality and Study Description, then just add new Layouts for all the different prior studies you might want to look at as shown below:

After setting up your various layouts for your protocol, you may find that occasionally some of the image boxes for a particular layout are empty. One reason why this can happen is because you have requested this layout to display images from a specific prior study in those image boxes, but no such study exists. If your layout is one that compares the current to the prior, then upon opening the current study and cycling to this layout, only those image boxes which are designated to display the current study will display images, while those designated for the prior study will be empty and instead display a message indicating that no such matching study was found.

If you do not want these layouts to be included when cycling through this protocol, you can set the Require Related Study Layout property to Yes. This will allow layouts for which no related study was found to be skipped.

Another reason why some of the image boxes for a layout may be empty is because the related prior study exists, but no images within that prior study match the filters you have specified for the image box. In this case, even if you set the Require Related Study property to Yes, this layout with empty image boxes will still be included when cycling through. This is because the study indeed exists; those image boxes are only empty because there are no images within the related study that match on the filters specified.

There is a similar function to exclude layouts for which no images from the current study are available for display. In this case, it is not because the study does not exist (the current study has to exist since it is the one you opened), but because no images within the current study match the filters for the respective image boxes in the layout. By setting the Require Primary Display Set to Yes, layouts containing empty image boxes for the current study will be skipped.

Common Problems

Q. My Hanging Protocol keeps showing empty image boxes - how can I fix it?

Most of the time, this is because:

•

There is an applicable study, but there is a difference between the values in the image headers and the values the Protocol is expecting (for either the Study or Display Set Layout properties). Follow the instructions in Basic Use to capture display sets from the study in question to a new Layout, and compare the values captured with those in the problematic Layout; there will likely be differences in the Study or Series Description. Also, see the item immediately following this one that discusses the importance of standardizing your studies.

•	There is no applicable study that meets the criteria specified in the Protocol. See the Recommendations above to learn how to create Layouts that can be skipped when a prior study simply doesn't exist.

Q. I keep having to create a new Hanging Protocol for every study I open - why?

No matter how powerful a Hanging Protocols implementation is, it can only work well if the data in the studies you are working with is consistent. Consider the study information in the following table:

Study (Modality, Description)	Series (Number, Description)
MG, Mammogram	1, Mammogram
MG, Bilateral	6, Bilat. Mammogram
MG, Bilateral Mammo	2, Mammo
MG, Mammogram (Bilateral)	4, Bilateral Mammo
MG, Screening	5, Scrn. Mammo
MG, Diagnostic	7, Diag. Mammogram

These are examples of the study information found in the DICOM Header. If these various descriptions were all used for one type of study, you can see why it would be difficult to define a Hanging Protocol the first time you open one of these studies--how can the protocol know that the next study is of the same type when the information in the DICOM Header is different? You will find yourself updating the protocol each time a new variation is used.

Inconsistent data can prove to be problematic over time. You may find other software out there that tries to solve this problem in any number of ways, usually by allowing you to manually define filters/operators like "Contains", "Starts With", or by adding an asterisk (*). This may be effective for a time, but you may quickly reach a point where these filters get so complex that you can no longer be certain they are always working and you may miss something important.

Even with the simplicity of capturing the viewer state to a Layout, inconsistent data can exceed the capacity of the software filters over time. You may reach a point where it is no longer practical to keep editing the protocols, for instance, when different types of studies use the same description variations, making them indistinguishable. As an administrator, it is imperative to solve the problem of data inconsistency at the source, which is in the studies themselves.

Q. I want to include a Display Set from a prior study in my Hanging Protocol - how do I do that?

If you have a study open with an appropriate prior, just drop a display set from it into an Image Box and capture the viewer state to a Layout as discussed in Basic Use. If you don't have an appropriate prior, you can:

1.	Manually edit the Study and Display Set properties for each Image Box in a Protocol Layout's properties (by clicking on the ellipses button ).

2.	Drop a display set from a similar study into an Image Box, capture it to a Layout, and manually edit the Study property and/or the Display Set property.

Q. How do I create a "Default" Protocol for a particular Modality?

This is also discussed in the fine-tuning section. To create a Protocol that will match for all studies of the same Modality, simply clear the Study Description property in the HP Designer.

Protocols where the Study Description is specified will be considered a "better match", so this Protocol will only be applied automatically when no other applicable Protocols are found for the study you opened.

Q. I want to see the same images, but with different Window/Level values - how do I do that?

Using the same images in the viewer, capture multiple Layouts, each time with a different Window/Level applied.

Then, the next time the Protocol is applied, you can just cycle through the layouts.

Q. When I compare the same breast with a prior study, I need one image to be flipped horizontally - how do I do that?

Just lay the viewer out with the images the way you want them (use the flip horizontal tool), and capture them to a new or existing layout.

Q. Why can't I include a Display Set for key images in my Hanging Protocol?

Key images are currently not supported by Hanging Protocols.