The promised land of a Digital Imaging and Communications in Medicine (DICOM) standard is a particular challenge for digital pathology where legacy infrastructure within complex hospital environments is undermining progress. But the growing call for interoperability means the problem can’t be ignored.
So let’s be pragmatic. While we work behind the scenes on fundamental digital infrastructure reforms, we need an immediate workaround. A way to bridge the gap between where we are, and where we want to be. That workaround is middleware.
The strategic imperative
Fragmented, siloed data is a substantial challenge for healthcare, with 60% of U.S. providers struggling to achieve seamless communication between their legacy and modern applications. This lack of interoperability can lead to critical gaps in patient care and increased operational overheads.
DICOM standardisation would solve the problem, but progress is slow, particularly in digital pathology where inherent infrastructure challenges make this a complex task. For example, DICOM didn’t extend its standard to include Whole Slide Images (WSIs) until 2010, meaning digital pathology vendors created their own solutions in the interim. The consequence is that most pathology departments own a range of different scanners, each with their own, proprietary format.
The table below highlights the broad range of WSI formats available:
| WSI file format | Extension | Compression |
| 3DHistech MRXS | .mrxs | JPEG, JPEGXR, PNG, BMP |
| Aperio / Leica AFI (Image Set) | .afi | JPEG, JPEG2000 |
| Aperio / Leica CWS | .cws | JPEG |
| Aperio / Leica SVS | .svs | JPEG, JPEG2000 |
| Carl Zeiss CZI | .czi | JPEG, JPEG XR |
| Carl Zeiss Laser Scanning Microscopy | .lsm | JPEG |
| Carl Zeiss ZVI | .zvi | RAW, PNG, JPEG, LZW, Deflate, JPEG2000 |
| GE Omnyx JP2 | .jp2 | JPEG 2000 |
| GE Omnyx RTS | .rts | JPEG |
| Hamamatsu DICOM | .dcm | JPEG, JPEG2000 |
| Hamamatsu NDPI | .ndpi | JPEG |
| Hamamatsu NDPIS (Image Set) | .ndpis | JPEG |
| Hamamatsu VMS | .vms | JPEG |
| Huron Technologies | .tif | JPEG, JPEG2000 |
| Inspirata RTS | .rts | JPEG |
| JPEG | .jpeg, .jpg | JPEG |
| JPEG 2000 | .jp2 | JPEG2000 |
| Jpeg XR | .jxr | JPEGXR |
| KFBIO | .kfb | JPEG |
| Leica DICOM Sup145 | DICOMDIR | JPEG |
| Leica LIF | .lif | RAW |
| Leica SCN | .scn | JPEG |
| Menarini DSight RAW | .ini | RAW |
| Microsoft Deep Zoom | .dzi, .xml | JPEG |
| Motic | .mdsx | JPEG |
| Motic | .mds | JPEG |
| Nikon ND2 | .nd2 | Deflate |
| Nikon TIFF | .tif, .tiff | JPEG, JPEG2000, LZW, Deflate, Raw, RLE |
| Objective Imaging (Glissando) | .sws | JPEG, BMP |
| Olympus OIR | .oir | RAW |
| Olympus VSI | .vsi | lossless JPEG, JPEG, JPEG2000, RAW |
| Olympus WebView | .xml | JPEG |
| Omero ZARR | .zarr | Blosc |
| Open Microscopy Environment OME-TIFF | .tf2, .tf8, .btf, .ome.tif | JPEG |
| Perkin Elmer QPTiff | .qptiff | LZW |
| Perkin Elmer Tiff | .tiff | LZW, JPEG |
| Philips iSyntax | .isyntax | iSyntax |
| Philips TIFF | .tif | JPEG, JPEG2000, LZW, Deflate, Raw, RLE |
| PNG | .png | PNG |
| Sakura SVSlide | .svslide | JPEG(sqlite2, sqlite3, mssql) |
| SmartZoom | .szi | JPEG, BMP |
| TIFF | .tif, .tiff | JPEG, JPEG2000, LZW, Deflate, Raw, RLE |
| Unic Tech | .tmap | JPEG |
| Ventana BIF | .bif | JPEG |
| Zoomify | .zif | JPEG, JPEG2000, LZW, Deflate, Raw, RLE |
Source: Pathomation
This lack of standardisation results in siloed scanners and software that can’t easily communicate or share data.
The missing link
Middleware is essential for solving the DICOM problem. It acts as a translator and broker between systems, allowing different WSI formats to interact.
Here’s how it works:
-
Image ingestion
An agnostic pixel broker ingests a Whole Slide Image (WSI) file from any scanner, eliminating the need for pathology labs to use separate viewers for different image types. The image is then converted into a smaller, standardized format.
-
Image management
Images can be served and managed from different locations including hardware, virtual, or cloud storage. Pathologists or AI workflows can also add metadata and annotations to the images at this stage, enriching them with patient information or other clinical details.
-
Image viewing
Web-based browsers are then used to view the images from anywhere with an internet connection, giving clinical teams on- and off-site access. This capability is especially beneficial for integrated health systems and hospitals with multiple locations.
-
Imagine integration
The system then integrates with Laboratory Information Systems (LIS), Anatomic Pathology LIS (APLIS), and Electronic Medical Records (EMR) via HL7 or FHIR. Additionally, Application Programming Interfaces (APIs) and SDKs (software development kits) can be used to facilitate integration with third-party AI software.
-
Image sharing
Middleware, such as the universal image management software described above, can seamlessly connect scanners, LIS, AI, and pathologists. This creates a workable system where digital pathology and other diagnostic disciplines can exchange, interpret, and utilize DICOM-incompatible data.
Breathing room
Middleware is not a substitute for the long-term goal of DICOM standardisation. That still requires significant changes to how data is captured, stored, accessed, and shared, and necessitates the rollout of the DICOM standard.
Having said that, middleware does offer us an immediate workaround and buys pathology departments the time they need to plan, purchase and implement robust DICOM infrastructure. And for burdened Directors of Digital Pathology, that breathing room is priceless.
By Liam Canavan, Healthcare Lead at Loadbalancer.org