U.S. patent application number 10/604673 was filed with the patent office on 2005-02-10 for method and apparatus of multi-modality image fusion.
Invention is credited to Avinash, Gopal B., Hertel, Sarah R..
Application Number | 20050031176 10/604673 |
Document ID | / |
Family ID | 34115672 |
Filed Date | 2005-02-10 |
United States Patent
Application |
20050031176 |
Kind Code |
A1 |
Hertel, Sarah R. ; et
al. |
February 10, 2005 |
METHOD AND APPARATUS OF MULTI-MODALITY IMAGE FUSION
Abstract
The present invention is directed to a method and apparatus for
fusing or combining functional image data and anatomical image
data. The invention, which may be carried out through user
interaction or automatically, enables composite and clinically
valuable images to be generated that display functional and
anatomical data acquired with different imaging systems. By
identifying fiducial markers on a functional data image and
correlating the fiducial markers with anatomical markers or indicia
on the anatomical data image, the respective images may be aligned
with one another before a composite image is generated.
Inventors: |
Hertel, Sarah R.; (Pewaukee,
WI) ; Avinash, Gopal B.; (New Berlin, WI) |
Correspondence
Address: |
ZIOLKOWSKI PATENT SOLUTIONS GROUP, LLC (GEMS)
14135 NORTH CEDARBURG ROAD
MEQUON
WI
53097
US
|
Family ID: |
34115672 |
Appl. No.: |
10/604673 |
Filed: |
August 8, 2003 |
Current U.S.
Class: |
382/128 ;
382/294 |
Current CPC
Class: |
G06T 7/33 20170101; G06T
7/38 20170101 |
Class at
Publication: |
382/128 ;
382/294 |
International
Class: |
G06K 009/00; G06K
009/32 |
Claims
What is claimed is:
1. A method of medical image overlap comprising the steps of:
determining at least two anatomical fiducial markers on a
functional image; determining corresponding points to the at least
two anatomical fiducial markers on an anatomical image; aligning
the at least two anatomical fiducial markers with the corresponding
points on the anatomical image; and warping the functional image to
fit constraints of the anatomical image while maintaining alignment
of the at least two anatomical fiducial markers and the
corresponding points on the anatomical image.
2. The method of claim 1 further comprising the step of accessing a
model of functional data prior to determining the at least two
anatomical fiducial markers.
3. The method of claim 1 wherein the functional image includes
perfusion data and the anatomical image includes anatomical data of
a coronary artery.
4. The method of claim 3 wherein the at least two anatomical
fiducial markers and the corresponding points on the anatomical
image correspond to ventricle grooves between ventricles of a
medical patient.
5. The method of claim 4 wherein the data acquired with PET and the
data acquired with CT include gated images.
6. The method of claim 3 wherein the perfusion data includes data
acquired with positron emission tomography (PET) and the anatomical
data includes data acquired with computed tomography (CT).
7. The method of claim 3 wherein anatomical constraints of the
functional image take into account cardiac motion.
8. The method of claim 1 wherein the step of determining the at
least two anatomical fiducial markers includes the step of locating
the at least two anatomical fiducial markers in a three-dimensional
image.
9. The method of claim 1 wherein the step of aligning includes
registering the functional image and the anatomical image by at
least one of translating, scaling, and rotating the functional
image and the anatomical image with respect to one another.
10. The method of claim 1 further comprising the step of enforcing
anatomical constraints during the step of warping by projecting a
nearest point on the functional image onto the anatomical image
while maintaining surface smoothness.
11. A diagnostic image generation system comprising: at least one
database containing functional and anatomical image data; and a
computer programmed to: determine at least a pair of fiducial
markers on a functional image; locate corresponding anatomical
indicia on an anatomical image; and generate a composite image of
the functional image and the anatomical image such that the
fiducial markers and the anatomical indicia are aligned and
anatomical constraints are considered.
12. The system of claim 11 wherein the computer is further
programmed to at least one of translate, scale, and rotate the
functional image and the anatomical image with respect to one
another such that the at least the pair of fiducial markers and the
anatomical indicia are cooperatively aligned.
13. The system of claim 11 wherein the functional image corresponds
to perfusion data acquired of a patient using PET and the
anatomical image corresponds to coronary artery data of the patient
acquired using CT.
14. The system of claim 13 wherein the functional image data and
the anatomical image data include gated data.
15. The system of claim 11 wherein the functional image is a 3D
approximate model of a patient anatomy.
16. The system of claim 11 wherein the computer is further
programmed to warp the functional image such that functional image
data is fit to anatomical constraints of the anatomical image.
17. The system of claim 11 wherein the computer is further
programmed to isolate ventricular grooves when determining the at
least a pair of fiducial markers.
18. A computer readable storage medium having a computer program
stored thereon, the computer program representing a set of
instructions that when executed by a computer cause the computer
to: access functional image data of a medical patient; access
anatomical image data of the medical patient; identify more than
one fiducial marker in the functional image data; identify
anatomical locations in the anatomical image data that correspond
to the more than one fiducial marker; and generate an image with
the functional image data super-imposed on the anatomical image
data that considers anatomical constraints.
19. The computer readable storage medium of claim 18 wherein the
set of instructions further causes the computer to align the more
than one fiducial marker with the anatomical locations.
20. The computer readable storage medium of claim 19 wherein the
set of instructions further causes the computer to warp the
functional image data to fit constraints of the anatomical image
data.
21. The computer readable storage medium of claim 18 wherein the
functional data includes positron emission tomographic perfusion
data of a coronary region of a medical patient and the anatomical
image data includes computed tomographic coronary artery data of
the medical patient.
22. The computer readable storage medium of claim 18 wherein the
functional image data and the anatomical image data are
geometrically collocated.
Description
BACKGROUND OF INVENTION
[0001] The present invention relates generally to diagnostic
imaging and, more particularly, to a method and apparatus of
combining or fusing functional diagnostic data and anatomical
diagnostic data acquired of a subject with imaging systems of
different modalities to generate a composite image for clinical
inspection.
[0002] The fusion of functional image data and anatomical image
data is a widely-practiced technique to provide composite images
for improved pathology identification and clinical diagnosis.
Typically, the functional and anatomical image data is acquired
using nuclear medicine based systems such as single-photon computed
tomography (SPECT), and positron emission tomography (PET) or
radiology based imaging systems such as computed tomography (CT),
magnetic resonance (MR), ultrasound, and x-ray. Generally, it is
desirable to "fuse" an image from SPECT or PET with an image from
CT or MR. In this regard, it is typically desired for the
functional image from SPECT or PET to be superimposed on the
anatomical image acquired using CT or MR.
[0003] Fusion of functional and anatomical data that has been
acquired separately with imaging systems predicated on different
imaging technologies can be problematic. That is, the functional
data may be acquired at a different time than the anatomical data.
As such, patient positioning between the separate data acquisitions
typically varies. Different size acquisitions with different slice
thickness and pixel sizes with different central points are also
not un-common. As such, for a clinically valuable composite image
to be produced, these differences as well as others typically
encountered, must be resolved.
[0004] One solution has been the development of a hybrid scanner
capable of acquiring PET and CT images during a single scan study
in such a manner to avoid many of the drawbacks enumerated above. A
combined PET/CT scanner, however, may not be feasible in all
circumstances. For instance, it may not be practical for a
diagnostic imaging center, hospital, or the like to replace
existing PET and CT systems with a combined imager. Moreover, a
combined PET/CT scanner, by definition, may generate a composite
image of functional and anatomical data acquired using PET and CT,
respectively. However, the scanner cannot provide a composite image
of PET and MR data. SPECT and MR data, or SPECT and CT data. As
such, a hybrid system may not address the myriad of diagnostic
needs required of a radiologist or other health care provider in
rendering a diagnosis to a patient.
[0005] Another solution that is consistent with conventional fusion
techniques fails to adequately address the drawbacks associated
with the overlaying of collocated functional and anatomical data
that are not registered. That is, present fusion protocols combine
data having a common coordinate alignment, but fail to register the
functional and anatomical images. Registering is commonly defined
as the process of aligning medical image data. This is based on the
premise that the functional and anatomical data sets were acquired
under identical physiological states and therefore can be fused
without taking additional measures into account. In this regard,
conventional fusion techniques orientate the functional and
anatomical data but do not take measures to sufficiently align the
functional and anatomical data. Furthermore, the image resolution
from PET and SPECT are limited by maximum energy resolution of
positron-emitting isotopes. The resolution of functional images
compared to anatomical images is notably inferior. Another
consideration that specifically affects cardiac imaging is the
considerable amount of motion that can add additional blurring to
any image set. The goal of anatomical imaging in the heart is to
observe the heart without motion. Functional imaging of the heart
can compensate for motion by dividing the imaging into bins but the
number of bins is the denominator when the total dataset is the
numerator. The number of coincidence events is limited to the
number of radioactive decay events and being able to observe as
much data as possible is desirable for a successful diagnosis. As a
result, the radiologist or other health care provider must decipher
a single composite image with the functional and anatomical
information, with respect to one another, being misaligned.
Additional post-fusion processing steps may be taken to correct the
misalignment of the respective images.
[0006] A conventional fusion of CT and PET image data is
illustrative of the above drawbacks. During a PET/CT cardiac
acquisition, the CT study is performed with ECG gating and the PET
study may or may not be performed with ECG gating. The anatomical
position of the heart typically changes relative to the ECG cycle.
During image processing the CT image is reconstructed from a
portion of the data centered on a selected phase during the cardiac
cycle in order to provide an image with the least amount of motion
blurring artifacts. The CT coronary arteries are then tracked and
segmented out of the CT image. The segmented images retain the
coordinate system of the original data frozen at one particular
phase of the cardiac cycle. A static or dynamic PET image may then
be reconstructed from the entire set of PET data that is averaged
over many ECG cycles. A gated PET image set is reconstructed for
each bin in the gated study. One of these bins may correspond to
the selected phase for which the CT data set was reconstructed. The
alignment may further improve with such conditions. These PET
images are then processed such that the left ventricle is segmented
based on the long axis of the heart. Using this information, a PET
3D model can be displayed in "model" space that approximates the
anatomical shape of a left ventricle. The CT image is then fused
with the PET image along the model coordinates to form a composite
image. However, the respective images from which the composite
image is formed are not registered because the coordinate systems
are not common to both image sets. Depending on the amount of image
blurring due to radioactive tracer energy, degree of cardiac
motion, and the modeling techniques, different amounts of
misalignment may be introduced. As such, the composite image
typically must undergo additional and time-consuming processing to
effectively align the functional data with the anatomical data in a
clinical area of interest to provide optimal images for
diagnosis.
[0007] Another classic multi-modality paradigm aligns internal or
external fiducial markers from a functional image with
corresponding anatomical points on an anatomical image. This
conventional fiducial marker-based system implements a manual
method of fusion that does not take local variations in the
datasets into account. The conventional automated rigid or
non-rigid body registration process uses mutual information as the
cost function for high-lighting differences between the functional
and anatomical images. The cost function therefore defines or
guides the registration process of the functional data to the
anatomical data. There are also methods that use fiducial markers
and rigid and non-rigid affine transformation to register images.
However, these automated methods do not use any localized
anatomical constraints to guide them. As a result, these
conventional approaches may only perform data-to-data fusion and,
as such, are inapplicable when fusion between data and modeled
data, or fusion between modeled data and modeled data is
desired.
[0008] Therefore, it would be desirable to design an apparatus and
method of fusing multi-modality images such that alignment is
resolved prior to the fusion of the separate images such that
post-fusion processing is reduced and supports fusion of modeled
functional and/or anatomical data.
BRIEF DESCRIPTION OF INVENTION
[0009] The present invention is directed to a method and apparatus
for fusing or combining functional image data and anatomical image
data that overcome the aforementioned drawbacks. The invention,
which may be carried out through user interaction or automatically,
enables composite and clinically valuable images to be generated
that display functional and anatomical data acquired with different
imaging systems. By identifying fiducial markers on a functional
data image and correlating the fiducial markers with anatomical
markers or indicia on the anatomical data image, the respective
images may be aligned with one another before a composite image is
generated. Warping is carried out that takes into consideration
anatomical constraints while maintaining alignment of the fiducial
and anatomical markers.
[0010] Therefore, in accordance with one aspect of the invention, a
method of medical image overlap comprises the steps of determining
at least two anatomical fiducial markers on a functional image and
determining corresponding points to the at least two anatomical
fiducial markers on an anatomical image. The method also includes
the step of aligning the at least two anatomical fiducial markers
with the corresponding points on the anatomical image and the step
of warping the functional image to fit constraints of the
anatomical image while maintaining alignment of the at least two
anatomical fiducial markers and the corresponding points on the
anatomical image.
[0011] According to another aspect of the invention, a diagnostic
image generation system includes at least one database containing
functional and anatomical image data and a computer programmed to
determine at least a pair of fiducial markers on a functional
image. The computer is also programmed to locate corresponding
anatomical indicia on an anatomical image and generate a composite
image of the functional image and the anatomical image such that
the fiducial markers and the anatomical indicia are aligned and
anatomical constraints are observed.
[0012] In accordance with yet another aspect of the present
invention, a computer readable storage medium has a computer
program stored thereon. The computer program represents a set of
instructions that when executed by a computer cause the computer to
access functional image data of a medical patient as well as
anatomical image data of the medical patient. The computer is then
programmed to identify more than one fiducial marker in the
functional image data and identify anatomical locations in the
anatomical image data that correspond to the more than one fiducial
marker. The set of instructions further cause the computer to
generate an image with the functional image data superimposed on
the anatomical image data that considers anatomical
constraints.
[0013] Various other features, objects and advantages of the
present invention will be made apparent from the following detailed
description and the drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0014] The drawings illustrate one preferred embodiment presently
contemplated for carrying out the invention.
[0015] In the drawings:
[0016] FIG. 1 is a schematic representation of a multi-node network
of medical imaging systems applicable with the present
invention.
[0017] FIG. 2 is a flow chart setting forth the steps of a
functional image data and anatomical image data fusion technique in
accordance with the present invention.
DETAILED DESCRIPTION
[0018] The present invention will be described with respect to a
process, which may be carried out through interaction with a user
or automatically, to generate a composite diagnostic image of
functional and anatomical data acquired separately with a PET
imaging system and a CT imaging system. One skilled in the art will
appreciate, however, that imaging systems of other modalities such
as MR, SPECT, ultrasound, x-ray, and the like may be used to
acquire the functional and anatomical data to be combined into a
composite image. Further, the present invention will be described
with respect to the acquisition and imaging of data from a cardiac
region of a patient. However, one skilled in the art will
appreciate that the present invention is equivalently applicable
with data acquisition and imaging of other anatomical regions of a
patient.
[0019] Referring now to FIG. 1, an overview block diagram of a
medical diagnostic and service networked system 10 is shown which
includes a plurality of remote treatment stations, such as Station
A referenced with numeral 12, and Station B referenced with numeral
14, which may include a medical treatment facility, hospital,
clinic, or mobile imaging facility. It is understood, that the
number of treatment stations can be limitless, but two specific
embodiments are shown with Station A and Station B, which will be
further explained hereinafter. The treatment stations 12, 14 are
connected to a centralized facility 16 through a communications
link 18, such as a network of interconnected server nodes. This
network of interconnected nodes may be a secure, internal, intranet
or a public communications network, such as the internet. Although
a single centralized facility is shown and described, it is
understood that the present invention contemplates the use of
multiple centralized facilities, each capable of communication with
each treatment station. Each treatment station has operational
software associated therewith which can be serviced by the
centralized facility 16.
[0020] The various systems disclosed are configured to be
selectively linked to the centralized facility 16 by a workstation,
which in the example of treatment station 12, includes a laptop
computer 20 or permanent workstation 26 connected to an internal
network 22. Such selective linking is desirable for accessing data
from the systems and transmitting data to the systems.
[0021] In general, a treatment site may have a number of devices
such as a variety of medical diagnostic systems of various
modalities. As another example, in the present embodiment, the
devices may include a number of networked medical image scanners 24
connected to the internal network 22. Alternately, a treatment
station or treatment site 14 can include a number of non-networked
medical image scanners 28, 30, and 32 each having a computer or
work station associated therewith and having an internal modem or
network connection device 34, 36, and 38 to connect the remote
treatment station to a communications link 18, such as the
internet, to communicate with centralized facility 16.
[0022] It is understood that each of the network scanners 24 has
its own workstation for individual operation and are linked
together by the internal network 22. Additionally, each of the
network/scanners may be linked to a local database 40 configured to
store data associated with imaging scan sessions, as will be
discussed shortly. Further, such a system is provided with
communications components allowing it to send and receive data over
a communications link 18. Similarly, for the non-networked medical
image scanners at remote treatment station 14, each of the scanners
28, 30, and 32 is connected to communications link 18 through which
they can communicate with the centralized facility 16. Furthermore,
each scanner 28, 30, 32 may include a database 42, 44, 46,
respectively, for storing scanning data. Scanning data may be
transferred to a centralized database 48 through communications
link 18 and router 50. The centralized database 48 is included in a
remote file server 52, where workstations and scanners, external to
the local intranet containing the centralized database 48, can
access the database as though located locally on the intranet 54.
More specifically, as will be described, workstations 20, 26 can
access the data stored in the centralized database 48, or other
remote database, such as database 40, as though the data were
stored in a database within the specific workstation requesting the
data.
[0023] The embodiment shown in FIG. 1 contemplates a medical
facility having such systems as MRI systems, ultrasound systems,
x-ray systems, CT systems, as well as PET systems, nuclear imaging
systems, or any other type of medical imaging system, however, the
present invention is not so limited. Such facilities may also
provide services to centralized medical diagnostic management
systems, picture archiving and communications systems (PACS),
teleradiology systems, etc. Such systems can be either stationary
and located in a fixed place and available by a known network
address, or be mobile having various net-work addresses. In the
embodiment shown in FIG. 1, each treatment station 12, 14 can
include any combination of the aforementioned systems, or a
treatment station may have all of a single type of system. Each
system is connectable and can transmit data through a network
and/or with at least one database 40, 48. However, it is understood
that the single representation of the centralized database 48 is
for demonstrative purposes only, and it is assumed that there is a
need for multiple databases in such a system.
[0024] As previously discussed, each of the systems and substations
described herein and referenced in FIG. 1 may be linked selectively
to the centralized facility 16 via a network 18. According to the
present invention, any acceptable network may be employed whether
public, open, dedicated, private, or so forth. The communications
links to the network may be of any acceptable type, including
conventional telephone lines, fiber optics, cable modem links,
digital subscriber lines, wireless data transfer systems, or the
like. Each of the systems is provided with communications interface
hardware and software of generally known design, permitting them to
establish network links and exchange data with the centralized
facility 16. However, the systems or particularly, workstations 20,
26 are provided with specialized software so as to communicate with
the centralized facility 16 and particularly with the remote
database 48 as though the data stored in the remote database is
located locally on workstation 20. In some cases, during periods
when no data is exchanged between the customer stations and the
centralized facility, the network connection can be terminated. In
other cases, the network connection is maintained continuously.
[0025] In one embodiment, the scanning data from as imaging
session, for example, on scanner 24, is automatically transmitted
from the scanner to the database 48. That is, database 48 is
automatically updated after each imaging scan is executed. Records
must be maintained as to the dosage used and catalogued according
to the particular diagnostic procedure as well as the individual
patient. From these records, the treatment facilities or
institutions may ensure conformity with dosage guidelines and
regulations. Further, as a result of maintaining an active database
storing scan parameter values of executed imaging sessions, a user
or prescriber of an imminent imaging session may query the database
to later retrieve scanning data for review from any workstation 20,
26 that is permitted to access the remote database 48.
[0026] As described above, the database having the scan parameter
values stored thereon may be accessed from a number of scanners
that are remotely located from the database. Furthermore, there is
no requirement that each scanner be physically located in the same
treatment station or facility. That is, a scanner located in
station 12 may electronically transmit and receive data from the
remote database 48 while simultaneously therewith any scanner 28,
30, 32 in station 14 may likewise transmit and receive data to and
from database 48. Later a workstation 20, 26 at any locality, for
example that may be remote to both the scanner 24 and the
centralized facility 16, can access the data from any scanner 24,
28, 30, 32 by accessing the centralized facility 16. Furthermore,
database 48 need not be located in a separate centralized facility
16. That is, database 48 may be located in either one of stations
12, 14 as well as be remotely located within that station or
treatment facility and the workstation 20, 26 requiring access to
the scanning data.
[0027] Referring now to FIG. 2, the steps of a processing technique
or method for aligning and registering functional and anatomical
data acquired from separate imaging systems built on separate
imaging technologies are set forth. The process may be automated or
guided through user interactions and commands.
[0028] Process 56 begins with the accessing of anatomical image
data 58 and functional image data or a model of functional image
data 60. A model of functional image data may be defined as
segmented image data with arbitrary or similar intensities as the
original functional image data from which the model was generated.
Arrow 62 indicates that the anatomical image data and the
functional image data are geometrically collocated. That is, the
anatomical and functional data are geometrically oriented about a
common coordinate system; however, the data are not registered.
[0029] Process 56 continues with the identification of anatomical
fiducial markers on the functional image 64. Preferably, at least
two reference markers are identified. The reference markers, as
will be described below, are used to identify corresponding
anatomical locations on the anatomical image. Additionally, it is
preferred that the fiducial markers be internal anatomical
features. However, external surface markers may be used, but the
external markers must be used during the acquisition of the
functional data as well as the anatomical data. This may be
problematic given that the functional data may be acquired at a
different time and location than the acquisition of the anatomical
data. For example, in a cardiac study, the reference markers may
include the ventricular grooves between respective ventricles of a
patient's heart.
[0030] Following determination and identification of fiducial
markers on the functional image, corresponding anatomical indicia
or points are determined 66 on the anatomical image. In the cardiac
study example given above, the ventricular grooves would be
identified on the anatomical image. Once the corresponding
anatomical indicia are determined and identified, the functional
image is overlaid 68 on the anatomical image such that anatomical
indicia and the fiducial markers are cooperatively aligned. In this
regard, in a preferred embodiment, the anatomical image remains
fixed and the functional image is superimposed thereon.
[0031] The aligning of the fiducial markers and the corresponding
anatomical indicia may be carried automatically by a computer
programmed to do so or may be done through user interaction with a
graphical user interface (GUI) displaying each of the images. In
this regard, the user, such a radiologist, technician, or health
care professional, may electronically "grab" the functional image,
"drag" the image age over the anatomical image such that the
fiducial markers and anatomical indicia are aligned, and "drop"the
functional image on the anatomical image. In another embodiment,
the user may identify or "highlight" the respective fiducial
markers and anatomical indicia, and then instruct the computer to
overlay or superimpose the functional image on the anatomical
image. Additionally, to sufficiently align the fiducial markers and
the corresponding anatomical indicia it may be necessary to carry
out various translation, scaling, and rotation processes.
[0032] Process 56 continues at step 70 with the warping of the
functional data to the anatomical data such that anatomical
constraints are met while maintaining alignment of the fiducial
markers and the corresponding anatomical indicia. In this regard,
the process tailors the warping process to anatomical constraints
of the anatomical data rather than a direct warping of the
functional and anatomical data. For instance, in the cardiac
example above, the health care provider will recognize that the
functional data corresponds to ventricular anatomy and the
anatomical data corresponds to the coronary artery. As it is common
for the coronary arteries to be located on the outer surfaces of
the ventricles, warping would be applied locally such that the
coronary arteries of the anatomical image lay on the outer surface
of the ventricular anatomy of the functional image. In this case,
enforcing the anatomical constraint requires that the nearest point
on the ventricular surface project onto the location of the
coronary artery while maintaining a smooth surface. As a result,
the functional and anatomical are more precisely aligned and the
composite image generated at step 72 is clinically valuable. As
noted above, anatomical constraints are application and modality
dependent and are useful for creating clinically meaningful
results. In this invention, the anatomic constraints are used to
define physical relationships between aspects covered by functional
and anatomic data, and to enforce known relationships between
functional and anatomic data.
[0033] Warping is an elastic registration process that may be used
to fuse or combine images acquired from scanners of separate
modalities. With warped, elastic transformation techniques,
multi-scale, multi-region, pyramidal approaches are implemented. As
such, a cost function is utilized to highlight differences between
the images on a scale-by-scale basis such that the differences are
optimized at every scale. That is, an image is sampled at a given
scale and then is segmented or divided into multiple regions.
Separate shift vectors are then determined or calculated at
different regions. The vectors are interpolated to generate a
smooth shift transformation which is applied to warp the image. The
image is then re-sampled and the registration process is repeated
at successive scales until a pre-determined final scale is
reached.
[0034] The above process has been described with respect to the
fusion of data between anatomical image data and either functional
image data or modeled functional image data. The process, however,
may be equivalently carried out to fuse modeled anatomical image
data and either functional image data or modeled functional image
data.
[0035] Therefore, in accordance with one aspect of the invention, a
method of medical image overlap comprises the steps of determining
at least two anatomical fiducial markers on a functional image and
determining corresponding points to the at least two anatomical
fiducial markers on an anatomical image. The method also includes
the step of aligning the at least two anatomical fiducial markers
with the corresponding points on the anatomical image and the step
of warping the functional image to fit constraints of the
anatomical image while maintaining alignment of the at least two
anatomical fiducial markers and the corresponding points on the
anatomical image.
[0036] According to another aspect of the invention, a diagnostic
image generation system includes at least one database containing
functional and anatomical image data and a computer programmed to
determine at least a pair of fiducial markers on a functional
image. The computer is also programmed to locate corresponding
anatomical indicia on an anatomical image and generate a composite
image of the functional image and the anatomical image such that
the fiducial markers and the anatomical indicia are aligned and
anatomical constraints are observed.
[0037] In accordance with yet another aspect of the present
invention, a computer readable storage medium has a computer
program stored thereon. The computer program represents a set of
instructions that when executed by a computer cause the computer to
access functional image data of a medical patient as well as
anatomical image data of the medical patient. The computer is then
programmed to identify more than one fiducial marker in the
functional image data and identify anatomical locations in the
anatomical image data that correspond to the more than one fiducial
marker. The set of instructions further cause the computer to
generate an image with the functional image data superimposed on
the anatomical image data that considers anatomical
constraints.
[0038] The present invention has been described in terms of the
preferred embodiment, and it is recognized that equivalents,
alternatives, and modifications, aside from those expressly stated,
are possible and within the scope of the appending claims.
* * * * *