A Crash Course on Handling DICOM Medical Imaging Data

Handling DICOM Medical Imaging Data - Presented by PostDICOM

As technology finds its way into every aspect of medicine, great advances have been made in the field of radiology. Radiology once depended on simple two-dimensional images that needed to be manually developed and fixed prior to viewing. Now, almost all forms of medical imaging have become digitalized and the spectrum of radiology includes not just digital radiographs but also CT scans, MRIs, ultrasound, and nuclear imaging. To maintain standards as well as uniformity across the varied types of medical imaging modalities, the concept of DICOM was introduced.

As a medical student or even a full-fledged radiologist, the prospect of dealing with so much technology can seem pretty daunting. This article will explain simply how you can handle DICOM files and exploit their full potential.

What is DICOM in Medical Imaging?

DICOM stands for Digital Imaging and Communications in Medicine. It is a standard, internationally accepted format to view, store, retrieve and share medical images. DICOM conforms to set protocols to maintain accuracy of information relayed through medical images.

Why do I need to learn about DICOM files?

As a student or practicing radiologist, all medical images that you see are likely to be in the DICOM format. DICOM medical imaging data cannot be opened by regular imaging software present on operating systems such as Windows or Mac OS. A special medical DICOM viewer needs to be installed in order to retrieve, view, and access DICOM medical image files. Therefore, it is important to know how to use this format, what are some relevant applications, and how to access the information and features contained within.

What does a DICOM Medical Image file contain?

Any DICOM medical image consists of two parts—a header and the actual image itself. The header consists of data that describes the image, the most important being patient data. This includes the patient’s demographic information such as the patient’s name, age, gender, and date of birth. The header may also give information on image characteristics such as acquisition parameters, pixel intensity, matrix size, and dimensions of the image. When a file explorer is opened to view DICOM medical imaging data, the header can give patient and image information. The header is usually coded to the image so that the patient to whom the image belongs can easily be identified. However, the header may sometimes be lost if the DICOM file is exported to other formats, such as JPEG. Sometimes, you may want to intentionally lose the header data, usually for the purpose of anonymization in research cases. This can only be done using specific software functions.

Where can I access DICOM files?

This depends on the purpose for which you want the files. If you are a patient and have had scans taken, you would probably receive a CD or DVD with images on it. If you are a medical student and want to view DICOM images for learning and study, you can download such images from online resources. If you are a radiologist and need to access files in order to interpret them and identify diagnoses, you will need to use a PACS server.

For a radiologist to access DICOM medical image files for the purpose of diagnosis and interpretation, a DICOM workstation must be available. This is usually a software application that is capable of complete integration with the PACS server: the application must be able to access and retrieve DICOM images from the PACS server as well as allow viewing and editing and then storing of edited images back again to the PACS server.

Notebook PostDICOM Viewer

Cloud PACS and Online DICOM Viewer

Upload DICOM images and clinical documents to PostDICOM servers. Store, view, collaborate, and share your medical imaging files.

How do I view a DICOM file?

Viewing DICOM medical images requires special software. There are basically two kinds of software for viewing DICOM medical imaging data—proprietary software and third party software. Proprietary software comes along with the hardware for medical imaging and is usually created by the same manufacturer. Once the CT or MRI scan is acquired by the machine, the images can be viewed at the same workstation through the DICOM medical imaging viewer. Proprietary software allows users to dynamically view sequential images and also allows reconstruction of these images. One major drawback is that these image files can only be viewed in the same location as the hardware. The images can be transferred to portable storage devices or to other computers on the network only by compressing the images (described in the section below). However, once images are exported, the ability to view and edit the original image is usually lost.

Third party software for DICOM image viewing is becoming increasingly common. These are standalone applications that can open DICOM files from any source—the internet, a CD or DVD, or a PACS server. The market today is flooded with DICOM viewing applications, with both free and paid options available. Each DICOM medical image viewer has its own set of features and you can choose among them depending on your specific requirements.

What can I do to a DICOM file in addition to simply viewing the image?

Today’s DICOM medical imaging viewers can do more than just help you view DICOM images. Some applications are sophisticated enough to improve the image quality as well as generate additional data from the acquired images which can aid in diagnosis. Some of the functions that you can perform, in addition to simply viewing the image, include

How do I Share and Export DICOM files?

The DICOM medical file of a single patient consists of multiple images, all of which are of high resolution. Therefore, the file size can be quite large (for instance, a single CT scan can run up to 35 MB). These files therefore need to be compressed before they can be shared and transferred.

There are two ways in which files can be compressed—lossless and lossy. In lossless compression, although the file itself is compressed, there is no loss of information. Therefore, the original file can be recovered at any time. However, this kind of compression requires a lot of processing and so lossless files are slow to open and slow to save. One cannot achieve a substantial amount of compression with this method. On the other hand, lossy compression allows reduction in file size by removing actual data. Usually, only redundant data is removed. Sometimes however, if excessive compression is done, the image quality can be adversely affected. With this method, files can be compressed to much smaller sizes than the original file.

The compressed file can be exported to various formats. Some of the commonest image formats include JPEG, TIFF, PNG and GIF formats.

Now that I’ve learned about DICOM software, what’s the next step?

The best way to put your DICOM medical imaging knowledge to use is to go hands-on. The first step is to download a DICOM application that suits your needs, and start using it. There are several free applications that you can use to gain experience. The most popular ones include PostDICOM, Horos, RadiANT, Miele LXIV, and Navegatium.

PostDICOM is a one-size-fits-all application that is just right for the beginner. It is compatible with most commonly used operating systems, including Windows, Mac OS, Linux, and Android platforms. It is quick and has an easy-to-use interface that is great for people who are just learning the basics of handling DICOM images. And at the same time, with advanced features including MPR, MP, MINIP and volume rendering, radiologists can use the application for improved diagnostic capabilities. PostDICOM comes with a unique cloud-based PACS that allows you to store DICOM files online and access them from anywhere, anytime. You can try, PostDICOM medical imaging software free of charge! Through a single accessible account, you can store the images to cloud-based PACS. If you feel that you need more storage space or more user accounts, options to upgrade are available. Try out PostDICOM today!

Notebook PostDICOM Viewer

Cloud PACS and Online DICOM Viewer

Upload DICOM images and clinical documents to PostDICOM servers. Store, view, collaborate, and share your medical imaging files.