By: Wouter Stomp, MD

IMAIOS’ mobile application is an atlas of human anatomy for the iPhone, and is available in three different packages: IMAIOS Mobile, e-Anatomy In App and IMAIOS Lite. They are the mobile equivalent of the anatomy part of the main IMAIOS website, a subscription-based service.

Also they are some of the most expensive anatomy apps available in the crowded app store. This review discusses the three different apps, their strengths, their differences, and whether they are worth the price.

The IMAIOS website is an online resource that features anatomy modules, e-courses on MRI physics, and clinical cases. The anatomy modules are organized by body part and imaging modality, including drawings, x-ray, CT and MRI images.

All modules contain labels organized by categories which can be individually enabled or disabled. Subscriptions to the website cost $8.99 for one day, $24.99 for one month and $69.00 for an annual subscription.

Pricing & Specs

As mentioned above, the iPhone app comes in three flavors: IMAIOS Mobile, e-Anatomy In App, and IMAIOS Lite. IMAIOS Mobile is meant for subscribers of the main website. It costs $29.99 and requires both an internet connection and a paid premium individual subscription. It contains 26 of the 33 anatomy modules from the website with over 4,000 images and 6,000 anatomy labels. Although the app requires an internet connection, this is only used to confirm the subscription status; all images are included in the app, making the app come in at a hefty 950 Mb (only download it when on a high speed connection).

e-Anatomy In App is the version for people without a subscription, allowing you to buy individual modules from within the app. It costs $3.99 and comes with the brain axial MRI and cranial nerves illustration modules fully activated. 22 other modules are included but are in demo-mode until they are purchased as part of one of three different packages (head and neck, thorax, abdomen and pelvis, and musculoskeletal), each costing $69.99, bringing the total cost for the whole deal to $213.96. Because all modules are included in the download, this one also comes in at 950Mb.

Finally, IMAIOS Lite is basically the demo version of the app, a relatively small 27.3Mb download containing just four modules. It costs $3.99 and includes the upper and lower limb diagrams and radiological anatomy. The e-Anatomy In App and IMAIOS Lite apps can both be used offline.

Analysis

For this review we used the IMAIOS Mobile app in combination with a one-month subscription. Installing over WiFi took several tries because of the large size of the app, so we would recommend downloading through iTunes if possible. After starting the app you are greeted with a welcome screen where you have to enter your IMAIOS username and password. After checking your subscription status you are taken to a screen listing all individual modules, sorted by anatomical region. After selecting a body part then you can select a individual body part for viewing.

The viewing screen has three tabs: views, labels and search. In the views tab, you can scroll through images by either moving your finger up and down or pressing left and right arrow icons. Images can be zoomed by pinching and images have sufficient resolution to actually do so. The amount of labels displayed on the screen at one time can be overwhelming, but helpfully, anatomy labels can be turned on and off by categories. The search tab displays all the available labels in the current module. Pressing one takes you to an image displaying the label. Again, because of the huge amount of label pins it can sometimes be hard to see which pin a label corresponds to.

Image quality is very good, the images can be zoomed in quite a bit without loosing too much detail. Flicking through the images goes smooth and without any noticeable loading time. Labels are available for just about any anatomical structure you can think of. Most images are available in two or three different orientations, making it a handy reference when looking at CT or MRI scans. 3D reconstructions of the lower limb arteries can be rotated by scrolling through the stack, giving a very good impression of the twists and turns they make. And where the scans are helpful for recognizing specific anatomy, the diagrams provide a solid basis to learn it from the ground up.

So is this the one anatomy app that rules them all?

Well we still have some gripes. One of the largest disappointments we ran into during reviewing this app is that it’s not available for the iPad. The iPhone’s screen feels cramped once you enable more than one or two categories of labels. Also what device would be more natural for easily browsing through large series of high-res images than the iPad?

The other major gripe is the price. Either you will need a subscription or you will have to pay at least $59.99 to see just one third of all the content. On the other hand, Monster Anatomy HD, an app we have reviewed before, and probably the app’s closest competitor, costs $18.99 for only the lower limb anatomy. Cheaper, but not that much cheaper when you consider the extra amount of content IMAIOS has. The last negative point we experienced was the internet connection that was needed for authentication. While it’s only needed during app startup, in our experience it can sometimes be hard to establish a connection deep within the hospitals, where this app is most likely to be used.

Pros

*Most comprehensive anatomy app available
*High-quality images from all body parts and modalities, including diagrams, X-ray, CT, MRI and 3D angiography reconstructions
*Labels for virtually any anatomic entity
*User-friendly app

Cons

*No iPad version!
*High price
*Internet connection needed for the subscription-based app

Conclusion

IMAIOS, in either one of its three varieties, is probably the best anatomy app currently available in the app store. However it also comes at a premium price and whether it’s worth it depends on your individual situation. For subscription members, the download would be a no-brainer if not for the $29.99 they still have to pay, which is not prohibitive, but a bit of a let-down if you are already paying for a premium subscription.

The e-Anatomy In App version comes at a somewhat reasonable price of $69.99 if you are only interested in one part of the body, however the complete package is in our eyes too large of an investment for a mobile app. A sensible price for such an app would be similar to that of the Lite app, at $3.99 for four modules.

The second let-down is the lack of an iPad app. This is one of those apps that would be perfectly suited for the iPad with its high-res images and abundance of labels, and it would certainly boost the value-for-money. All-in-all this is a great app, but whether it is worth the cost is very dependent on how interested you are in anatomy.

For medical students, it’s probably too pricey, but for people working in fields like radiology, surgery or pathology, where anatomy plays a big role, it could be a good investment.  If an iPad version was to be released, the picture would become different, because it could then actually replace costly paper anatomy books — we can only hope.

iTunes links:

IMAIOS Mobile

e-Anatomy In App

IMAIOS Lite

Wouter Stomp is a physician from the Netherlands, currently doing a PhD in radiology