Sup223
Archive Inventory
This Supplement introduces a new Repository Query SOP
Class to obtain an inventory of a repository system, a
composite Inventory IOD that is the equivalent persistent
instantiation of such an inventory, an Inventory Creation
SOP Class to initiate asynchronous creation of Inventory
SOP Instances, and SOP Classes to transfer, query and
retrieve Inventory SOP Instances.
There are considerable use cases for these new services:
Porting large DICOM repositories from one image management
system (PACS or VNA) to another.
Migration approaches need to operate at large scales, and
handle both on-premises and remote (e.g., cloud-based)
storage.
Migration often occurs when either the source system or
the destination, or both, are in clinical operation, but
systems designed and configured to handle the throughput
of regular operations might not have capacity for the
additional massive input/output requirements of migration.
Healthcare institutions merge previously disparate
repositories into an enterprise repository.
Research use cases, including artificial intelligence and
machine learning, where bulk access to the archive is
desirable, and such uses might leverage some of the same
mechanisms developed for migration.
PACS audit and quality control may also utilize some of
the standardized functionality developed for migration,
such as an archive inventory and metadata to identify the
data produced by a particular unit or by a particular
modality.
A key requirement for migration (and other use cases) is
the ability to have an inventory of all studies, series,
and instances from an archive.
This Supplement specifies a new Repository Query SOP Class
that includes features supporting a sequential set of
queries intended to produce a complete repository
inventory. These features include well-defined behavior
for queries that reach a system limit for number of
responses, and an ability to resume at the next record in
a subsequent query.
The current Query Service (DIMSE or equivalent DICOMweb)
has limitations on number of responses and the synchronous
protocol require the use of a possibly very large number
of partial query requests, with undefined behavior when
query limits are exceeded.
This Supplement also specifies an Information Object
Definition capable of encoding an inventory of all
studies, series, and instances in a repository. This is
functionally equivalent to a query response that returns
an inventory of the entire repository database, or a
subset thereof as specified by key attributes.
The Supplement further defines a mechanism to remotely
initiate the production of the inventory through a DICOM
network service and allow production to proceed
asynchronously.
Only inventory of patient-related studies, series and
instances is defined. Inventory of non-patient objects is
out of scope for this Supplement.
This supplement is not in itself a complete standard for
migration.
Supplement 223 was voted Final Text and will be
incorporated in the next publication of the standard.
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Sup227
Elastography SR Template
This supplement to the DICOM Standard introduces
an SR section template for Ultrasound Elastography results
and a General Ultrasound Report within which it can be
used.
Ultrasound elastography is used on tissues including
liver, breast, prostate, and tendon. In shear wave
elastography (SWE), the ultrasound system measures shear
wave speed (SWS) and derives a value for elasticity (in
kPa) from that.
Some systems also assess viscosity (which can be
correlated to inflammation) by generating a value such as
shear wave dispersion slope.
In strain elastography (SE), elasticity/stiffness is
assessed qualitatively by comparing the compression of
tissue in a target region to that of tissue in a nearby
reference region.
Supplement 227 was voted Final Text and will be
incorporated in the next publication of the standard.
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Sup213
2G-RT: Enhanced RT Image
The Supplement addresses imaging within Radiotherapy
treatment sessions and acquiring patient positioning
information.
The supplement adds three IODs. Two for supporting
projection images and one IOD supporting acquisition
instructions for images and other artifacts to be used for
patient positioning.
The Enhanced RT Image covers the images with a smaller
number of frames, where the per-frame functional group
macros are populated for all frames.
The Enhanced Continuous RT Image covers images which are
continuously acquired, resulting in high number of frames
due to a high frame rate. With frame level attributes not
being repeated for each frame this image type is more
efficiently and sparsely populated.
Both IODs represent projection images of the patient
geometry in relation to the treatment device
equipment. They may be used to guide the positioning of
the patient in respect to the treatment delivery device to
ensure delivery of the therapeutic dose to the intended
region. They may also be used to verify the position of
the patient when acquired prior, during or after the
delivery of the therapeutic radiation.
The Supplement additionally specifies a new IOD to convey
parameters instructing devices on how to acquire images or
other artifacts used for patient position verification in
Radiotherapy treatment delivery sessions.
RT Patient Position Acquisition Instruction contains the
definition of the procedures, devices, and related
parameters to be used for the assessment and/or
verification of the patient position. The technical
parameters can be defined on any level of detail as needed
by a specific device.
Procedures can be paired to represent related operations
like e.g. a paired orthogonal MV and kV image
acquisition.
The scope of therapeutic radiation whose
position is verified is specified by referencing SOP
Instances identifying objects like RT Radiation Set IOD of
RT Radiation IODs.
Supplement 213 will be presented further to the base
standard group before being voted upon for Final Text.
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Sup231
Adaptive dynamic range Greyscale Presentation State
This supplement defines a new SOP Class that relaxes the
requirements of the existing GSPS SOP Class for modalities
in which the dynamic range varies between images or
frames.
This SOP class will address handling of Modality LUT in
the referenced image(s) and not require the GSPS Modality
LUT Module.
The rationale behind this supplement is that PS3.4 N.2.1.1
requires the per image Modality LUT be ignored in the
presence of a GSPS object.
This is problematic in cases such as PET or MR, in which
the dynamic range of the measured values varies between
images.
This forces the GSPS creator to render a GSPS object for
each image.
Supplement 231 will be presented further to the
base standard group before going out for Letter Ballot
voting.
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Sup228
DICOMweb API for Server-Side Volumetric Rendering
This supplement introduces web services that enable a user
agent to request server-side volumetric rendering of 3D
volumes.
Volumetric representations are:
- 3D volume rendering (VR)
- Maximum Intensity Projection (MIP)
- Multiplanar Reconstruction (MPR)
There are scores of use case scenarios:
For example, an ER stroke patient is referred for a CT. Non-contrast and CT angiogram images are acquired to rule out hemorrhage and intravascular thrombus, respectively.
Images are reviewed on a zero-footprint viewer by ER physician. The viewer includes a hanging protocol that displays lossless JPEG-LS multi-frame images of thick slab axial MIPs of the CTA.
This is the result of a RESTful service request with a pre-identified rendering mode, slab thickness and spacing. The ER physician interrogates images that best demonstrate the Circle of Willis.
The DICOM Web API for Server-Side Volumetric Rendering offers methods to render a volume of Input Instances or a Volumetric Presentation state via RESTful request to an origin sever at the time of image interpretation or procedure planning.
DICOM Web API for Server-Side Volumetric Rendering is not intended as an alternative to Volumetric Presentation states, but a complement in enabling user agents to request a 3D or 3D temporal rendering without having specify the numerous and complex parameters to do so.
Volumetric Presentation states (established in Supplements 156 and 190) provide a method to save persistent rendering parameters, presentation, graphic annotations, animation, cropping, and segmentation performed off-line, prior to image interpretation or procedure planning.
This supplement considers a basic and an advanced (3D aware) client scenario.
The basic client, capable of fundamental operations to select the rendering type, select a rendering protocol, or to manipulate volumetric view and transformations.
For the basic client, this supplement focuses on the 20% of requirements that satisfy 80% of the interoperability needs. It supports pan, zoom, rotate, set render type, add annotations.
The 3D Aware client, capable of defining and manipulating the full breadth of parameters contained within the Volumetric Presentation State IOD. In this case, capabilities are limited to Volumetric Presentation State definition and origin server capabilities. It support more complex features like color, shading, lightning, segmentation, cropping, blending and transparency.
Returned rendered object formats include jpg, gif, png and animated-gif.
This supplement will be further presented to the base standard before going out for public comment voting. View details »
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Sup229
Photoacoustic Imaging
This Supplement to the DICOM Standard introduces a new IOD and a
new storage SOP Class for encoding and storing photoacoustic
images.
Photoacoustic imaging (PAI) is an imaging modality that enables
imaging optical absorption in biological tissues with acoustic
resolution.
Contrast is generated through absorption by chromophores that
range from intrinsic absorbers such as hemoglobin and melanin to
extrinsic agents such as indocyanine green (ICG) or diverse types
of nano-particles.
Excitation at multiple wavelengths allows the modality to
discriminate individual chromophores. Prospective applications in
the space of clinical imaging range from classification of breast
cancer lesions through screening of sentinel lymph nodes to
assessment of inflammation.
Photoacoustic Imaging is in widespread use in preclinical research
labs and is recently being translated to clinical applications in
first commercial implementations.
Many (but not all) PAI implementations integrate active pulse/echo
ultrasound in a hybrid imaging system to capitalize on
well-established contrast for anatomical information.
The scope of this IOD is the Photoacoustic (PA) images and
processed images that may be derived from a combination of these
PA images.
Complementary images such as pulse/echo ultrasound are represented
by their native DICOM IODs.
Albeit fusing PA images with US images is the presently most
common scenario, the particulars of the fusion are beyond the
scope of this IOD but an example is provided.
The supplement will be presented further in base
standard meetings before going out for public
comment voting.
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Sup230
TLS Security Update 2021
This Supplement adds two new Secure Transport
Connection Profiles and retires several others. The
IETF recently updated the Best Current Practice
document called BCP-195.
The new document no longer
allows downgrading to TLS 1.0 or 1.1, which
necessitates DICOM retiring Secure Transport
Connection Profiles that are based on those
protocols.
The new version of BCP-195 is more in
line with DICOM's B.10 Non-Downgrading BCP 195
Secure Transport Connection Profile. In addition,
the Japanese government has modified their
guidelines for "high-security type" devices, hence
the old Extended BCP 195 profile (B.11) is also now
out of date, needs to be retired, and a new profile
created that reflects the new revisions.
The supplement will be presented further in base
standard meetings before going out for public
comment voting.
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Sup232
JPEG XL Transfer Syntax
This supplement covers the addition of the JPEG XL
Transfer Syntax to Part 5 of the standard.
The JPEG XL Image Coding System (ISO/IEC 18181) has
a rich feature set and is particularly optimised for
responsive web environments, so that content renders
well on a wide range of devices. Moreover, it
includes several features that help transition from
the legacy JPEG format.
Migrating to JPEG XL reduces storage costs because
servers can store a single JPEG XL file to serve
both JPEG and JPEG XL clients. Existing JPEG files
can be losslessly transcoded to JPEG XL,
significantly reducing their size.
These can be restored into the exact same JPEG file,
ensuring backward compatibility with existing
JPEG-based applications.
This supplement will be further presented to the base
standard before going out for public comment voting.
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