5. 의료영상 및 PACS
2011. 4. 13
안병익(biahn99@gmail.com)
Mcomputing.tistory.com
@LBSAHN
U-HealthCare System
Medical Imaging Tech & PACS
•
•
•
•
•
CT
MRI
PET/CT
PACS
DICOM
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Why use different methods of imaging ?
Cost Effectiveness
• A good guiding principle in many walks of life is …
Always pick the simplest solution for your problem.
• In many cases the cheapest solution is the best.
You do not need to give every pregnant mother in the
country an MRI scan.
• The capital cost of installation varies widely:
Ultrasound
£20k - £100k
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X-ray CT
£500k - £1M
MRI
£2M - £4M
PET
>£5M
What is the CT?
• Mathematical transform to the measured data.
• Reconstruct n dimension function (image)
=> projection data of n – 1 dimensio
n
• Radon Transform (1917)
“Two dimension and three dimension object ca
n be reconstructed from the infinite set of proj
ection data”.
• The First CT: 1973 in the U.S.
4 minutes scan, thickness of 10mm
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Concept of CT
・Getting the shape by back projection of the projection data.
・For example, outward view is the quadrangle => it is the cylinder
CT
Algorithm
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CT
(From Siemens)
(From Picker)
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Basic principle of CT
-Reconstruction of 2 dimensional image-
Projection Data curvilinear integral of absorption coefficient regarding Y
y
y
object
x
x
X-ray
tube
Data Acquisition field
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Reconstruction field
Simple Backprojection
Blur
Basic principle of CT
-Reconstruction of 2 dimensional image-
Projection Data
y
x
＊
Filtered Projection data
Reconstruction Filter
x
x
ω
or
x
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Multidirectional
Backprojection
Filtered Backprojection
Reconstruction process
f ( x , y ) : absorption
I 0 ( x ) : incident
attenuated
projection
Filtered
coefficien
intensity,
intensity
t (to be reconstruc ted) [Np/m]
I ( x ) : attenuated
intensity
f ( x , y ) dY

: I ( X )  I 0 ( X )e

data : p ( X ,  ) 
data : p f ( X ,  ) 

f ( x , y ) dY  ln
I0 ( X )
I(X )
1

2


P (U ,  )  U  e
jUX
dX
wher e P (U ,  ) is 1D FFT of p ( X ,  )
Back projection
: f ( x, y ) 


0
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p f ( x  cos   y  sin  ,  ) d 
Reconstruction process
Radon Transform
: P (U ,  )  F (U , 0 )
where F ( u , v ) is 2D - FFT of f ( x , y )
Data acquisition at angle : 0 – 180 degree
Obtain F(u,v) and then 2D IFFT -> reconstruction
Radon Transform is equivalent to Filtered backprojection !
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Example of Simulation
Model Image
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Simple
Backprojection
Filtered
Backprojection
Magnetic Resonance Imaging
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Magnetic Resonance
• Uses equipment prod
ucing magnetic fields
from 0.5 Tesla to 3 Te
sla
• Earths magnetic field
is 50 microtesla
• Cost of equipment is
approx £700k per Tes
la
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Obtaining the Data
• All atoms have a magnetic field or orientation
• When placed in a strong magnetic field the at
omic nuclei align with that field
• Pulses of Radio Frequency aimed at area of int
erest in the body
• Imparts high energy state to the nuclei of thos
e areas
• Relaxation of that state produces resonance w
hich can be detected
• Location and intensity will translate into pixel l
ocation and intensity
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Slices
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Image Processing
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Image Manipulation and Enhancemen
t
• Two time frames T1 and T2 relate to perc
entages of nuclei which have resumed n
ormal state
• T1 improves resolution
• T2 improves sensitivity
• Contrast media can be introduced
• fMR can monitor specific physiology
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Anatomy or Physiology?
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Using Data Manipulation
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Image Manipulation
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When Do We Use MRI?
• Excellent for soft tiss
ue imaging
• Resolution is good
• Does NOT use ionisin
g radiation but does
have some safety iss
ues
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MR Versus CT
MR
Digital manipulation
Non-ionising
Non-invasive
Good for soft tissue
Can image physiology
Technique can be altered
to account for data requi
red
• Expensive
•
•
•
•
•
•
•
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CT
Digital manipulation
Ionising Xrays
Non-invasive
Good for range of tissue
types, soft tissue to a les
ser extent
• Can only image physiolo
gy when used with other
modalities
• Variation in technique po
ssible
• Relatively Cheap
•
•
•
•
•
PET / CT System
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25
PET / CT 란 ?
• PET / CT란 양전자 방출 촬영기(Positron Emission
Tomography)와 컴퓨터 단층촬영기(Computed
Tomography)를 하나로 합친 장비이다.
• PET / CT 장비는 암 진단에 효과적으로 사용되고 특
히 종양을 CT, 감마카메라 등에 비해 월등히 앞선 시
기에 진단할 수 있게 되어 암의 조기 진단을 가능하
게 한다.
• 검사시간을 크게 단축하여 환자의 고통을 덜어주고
환자에 대한 병원의 의료서비스의 질이 한층 높아질
것으로 예상된다.
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PET / CT 란 ??
• PET은 양전자 방출하는 방사성의약품을 이용하여 체
내의 미세한 변화를 영상화 하는 최첨단 검사이고, 이
용하는 약품에 따라 당 대사, 단백질 대사, 핵산대사,
혈류 등의 다양한 체내변화를 영상으로 얻을 수 있으
며, 이중 포도당대사를 관찰하는 검사가 가장 흔히 쓰
인다.
• PET/CT는 이러한 PET과 CT를 동시에 시행하는 검사
이다.
• PET만 시행했을 때 생길 수 있는 정상조직에 의한 진
단오류를 최소화하고 진단성능을 향상시킬 수 있게
한다.
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PET / CT 검사원리
• PET/CT에서는 양전자를 방출하는 포도당 유사체를 이용합니다.
인체 내에 주사 된 포도당 유사체는 암세포에 집적되고 방출된
양전자(+)는 주변의 전자(-)를 만나서 소멸반응을 일으킨 후 서
로 반대방향을 가지는 511 KeV 에너지의 두 개의 감마선으로
변환됩니다. 이 감마선들은 PET/CT의 원형동시계측회로에서 검
출되어서 컴퓨터에 위치 정보를 전달하게 되고 컴퓨터에서는 인
체 내에 어느 곳에 이상이 있는지를 영상으로 표현해 줍니다.
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PET / CT 장점
– 암의 조기발견
• 크기가 작아 CT 나 초음파 등 기존의 검사에서 놓치기 쉬을 정
확히 진단하는데 큰 도움이 된다.
– 암의 분포진단
• 암이 어디까지 퍼져있는지 판단. 암의 재발진단.
– 암 치료 계획에 이용
• 암이 발견될 경우 , 바로 치료방침을 세울 수 있는 정보까지 제
공받을 수 있다.
– 검사시간의 감소
• 최대 40% 절약하여 불편한 환자의 불편을 감소시키고 병원의
생산성도 높이고있다.
• 한 번의 촬영으로 전신을 검사할 수 있다.
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PET / CT 단점
– 분화도가 좋은 간암이나 조기위암 등의 진단성능은 조금 떨
어진다.
– 신장 , 요관 , 방광 , 전립선 등 비뇨생식기계 암은 소변으로
인해 진단에 주의해야 한다.
– 대사항진이 높지 않은 3~4 mm 이하의 작은 암은 발견되지
않을 수도 있다는 한계점을 고려해야 한다 .
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PET / CT로 알 수 있는 질환
• PET/CT 의 가장 대표적인 적응증은 암 입니다 .
• 암에서 PET/CT 는 , 암의 발견 , 양성 및 악성의 감
별 , 치료를 위한 병기 설정 , 치료 후 재평가 , 재발
진단 등 , 암 진료의 전 영역에서 활용되고 있습니다 .
• 일단 암으로 진단 받고 치료 및 추적 과정에 들어 가
면 담당 의료진의 책임 하에 중요한 진단 평가 수단
으로 당연히 이용되지만 , 최근에는 암을 발견하는 검
진에 PET/CT 를 이용하는 것이 관심을 끌고 있습니
다.
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PET / CT 검사종류
• 전신 PET / CT
• 뇌신경계 PET / CT
• 심장 PET / CT
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전신 PET / CT
• 방사선의약품을 팔에 정맥주사하고 40분 후에 몸 전
체를 CT촬영을 하고, 이어서 PET검사를 시행한다.
• 폐암, 유방암, 대장암, 두경부암, 림프종, 흑색종, 근골
격계암, 자궁경부암, 난소암 등의 조기발견 및 전이여
부, 양성과 악성 종양의 감별, 암의 병기결정, 재발여
부판정, 항암화학요법제와 수술의 치료효과 한정, 환
자의 예후 예측등이 가능하다.
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신세포암으로 수술 후 별
증상 없었으나, PET/CT시
행 후 복부에 임파선 재발
을 확인할 수 있다.
PET/CT시행 후 간 좌우엽 전
반에 퍼져 있는 암 조직과 , 동
시에 우측 갑상선에서 대사 증
가를 보이는 종양이 발견되었
고 , 간암으로 확정된 환자이
다
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뇌신경계
PET / CT
• 간질환자의 수술전 검사, 파킨슨씨병, 치매(알츠하이
머병)의 진단. 뇌종양, 뇌혈관질환의 진단에 사용한다.
• 기억력 감퇴 등 치매가 의심되는 증상이 있어 이를
조기발견해서 질병진행 억제 치료를 한다면 치매를
예방하는데 도움이 됩니다.
• 일부 운동신경계 질환의 감별진단을 원할 때 이용한
다.
• 뇌암 진단 받고 방사선치료를 받은 뒤 잔존하는 암이
있는지의 여부를 MRI에서 알기 어려울 때 이용한다.
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심장 PET / CT
• 협심증과 심근경색과 같은 관상동맥 질환을 진단한다.
• 허혈성 심장질환에서 보다 정확한 생존심근부위의 판정
을 원할 때 심근 생존능력을 평가하여 치료방법을 결정
하는데 시용한다.
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What is PACS ?
P: Picture, Images & Reports
A: Archive, Online, Near line, Offline
C: Communication, Networking, Transfer Protocols
S: System, Components & Architecture
PACS: for storage and distribution of images and i
nformation when necessary
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PACS: Small or Large
Web Server Distribution
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Scale of PACS
• No. of Beds in Hospital/ Exams per year
• No. of Modalities
• No. of Switches
Considerations:
System connectivity, expandability, reliabilit
y and cost-effectiveness
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Types of images
• 1D, 2D, 3D, 4D
• Different DICOM Modality type: Cardiac / PET / 4D U/
S…..
• Image size: Resolution and bit depth
• Image quality: Bit Depth and resolution
• Color / Monochromatic
• Exam. Size: image size x no. of images
• Structured Reports
• New DICOM IOD:
Endoscopic & Microscopic images / ECGs / Security Pr
ofiles…..
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1D, 2D, 3D, 4D, fusion
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1D, 2D, 3D, 4D, fusion
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Image Resolution/ Bit depth
U/S
DF
CR
CR Mammogram
256 x 256
8 bit
65 KBytes
1k x 1k
10 bit
1.25 MByte
2k x 2.5k
12 bit
4k x 5k
7.5 MByte
12 bit
30 MByte
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Properties of image
• Bit depth
• Grayscale or color
• Resolution in pixe
l
 Example image si
ze of mammogra
m = 4k x 5k x 12
bit = 30 MB
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PACS Architecture
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PACS – Central Architecture
DICOM
Modality
Non-DICOM
Modality
Diagnostic
Workstations (DICOM)
Gateway or
Frame Grabber
Clinical
Workstations (DICOM)
Image
Server
(RAID)
Diagnostic
Workstation
Film
Digitizer
Computed
Radiography
or DR
CR/ DR QA
Workstation
Web Server
Data Base
Server
Archive
RIS
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Central Architecture
• Image Server and Database Manager is t
he HEART
• Any image, any where, any time
• Unique central copy
• Easy update of data
• Requires high performance servers
• Potential single point of failure at server
• Bandwidth demanding
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PACS – Distributed Architecture
DICOM
Modality
Gateway or
Frame Grabber
Non-DICOM
Modality
CR QA
Workstation
Film
Digitizer
Diagnostic
Workstations
(DICOM)
Web Server
Diagnostic
Workstation
Data Base
Server
Archive
Computed
Radiography
RIS
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Clinical
Workstations
(DICOM)
Distributed Architecture
• Exams are routed from modality to select
ed workstations
• Complex routing algorithms based on de
partment / user preference
• Difficult to support concurrent review of i
mages
• Less destructive for failure at database se
rver
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Components of PACS
•
•
•
•
•
•
•
•
HIS/ RIS
Broker
ePR gateway
Database Server
Image Server (RAID)
Long Term/ Near line Archive
Networks
Digitizer
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Components of PACS
•
•
•
•
•
•
•
•
Acquisition Gateways
Non-DICOM modality gateway
DICOM Print Server
Media Server
Reporting Server
Monitor QC Server
Web Server
Workstations
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PACS layout 1
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PACS layout 2
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PACS layout 3
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PACS Components
ePR gateway
Enterprise Archive
DICOM
Modality
Diagnostic
Workstations (DICOM)
Through Acq.
gateway
Non-DICOM
Modality
W/S QA Server
Clinical
Workstations (DICOM)
Image
Server
(RAID)
Gateway or
Frame Grabber
Diagnostic
Workstation
Film
Digitizer
Web Server
Data Base
Server
Computed
Radiography
or DR
LTS Archive
SAN/NAS
CR/ DR QA
Workstation
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Broker for
RIS/HIS
Media Server
Acquisition (DICOM) Gateway
HIS/RIS
Interface
(Broker)
DG
RIS
CT
W/S
M
R
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R&F
NM
PCs
CR QA
CR
Film
Digitizer
XRAY
Frame
Grabber
US
Role of Acquisition gateway
• Compression/ decompression and security
• Check the images for integrity
• Convert to PACS format (header, byte-ord
er, matrix size)
• Queue for images (priority) to database se
rver (background)
• Share the workload and no point of failur
e for multiple Acquisition gateway
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Database Server and Image Server
Database
Server
RAID
HIS/RIS
Interface
(Broker)
DG
RIS
CT
W/S
M
R
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R&F
NM
PCs
CR QA
CR
Film
Digitizer
XRAY
Frame
Grabber
US
Database Server (PACS controller)
• The Heart of the system
• Integration cross point between HIS/RIS an
d PACS (status update)
• Create and manages patient folders
• Manage reading worklists and user profiles
• Manage data transfer within the system
• Support data mining and teaching folders
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Image Server (RAID)
• Online (rapid access) exam storage and d
istribution device
• Support simultaneous exam input and o
utput transfer operations
• Up to Three months of storage capacity
• Scalable capacity
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What is RAID
Redundant Array of Independent Disks
Bandwidth equal to sum of disk transfer rates
Highest speed disk storage available
Hot Swap
1
2
2 MB/s
3
4
5
6
7
Image
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8
Parity
Disk Array
16 MB/s
RAID 5 configuration
• If disk fails, disk can be
rebuilt- fault tolerant
• High data transfer rate f
or read, write slower
• Min. 3 disks to start
• Array capacity is N-1
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Bandwidth
Bandwidth is a measure of the informati
on (data) carrying capacity of a network
10/100/1000 MB/sec
Information Flow
Data Pipe (Network)
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Network Bottleneck
The bandwidth of an information delivery system i
s limited to the bandwidth of the slowest compon
ent in the system
Network Bottleneck
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Data Compression
Data compression reduces the information rate
a network must support
Uncompressed Data
Compressed Data
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Lossless Image Compression
I-D=0
C
I
D
Decompressed image is identical to original im
age
JPEG lossless compression
Average compression of 2:1 for x-ray images
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JPEG 2000 Compression
• Selected parts of the image can be defined as
Regions of Interest, they can then be delivered
before other parts of the image, or losslessly,
whilst other parts of the image that are less cri
tical use normal lossy compression
• JPEG 2000 codestream can be ordered to deliv
er images of lower resolution before the full i
mage can be transmitted
• Motion JPEG 2000 does not have any form of
extrapolation (and hence potential distortion) i
n the time domain. Each frame is a separate J
PEG 2000 coded image
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JPEG 2000 images
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Storage Device (Long Term)
Database
Server
RAID
MOD
DLT
HIS/RIS
Interface
(Broker)
DG
RIS
CT
W/S
M
R
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R&F
NM
PCs
CR QA
CR
Film
Digitizer
XRAY
Frame
Grabber
US
Types of storage media
Media
DVD
MOD
DLT
9840
AIT2
WORM
3.8
5.2
35
20
50
Less
Expen.
Expen.
Expen.
Cheap
Most
Expen.
Load + Very fast Very fast 113 sec
Assess
5
5.1
5
Max. T
rate
MB/s
15 sec
45 sec
10
6
GB
Cost
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Long Term Archive



Used to store digital data for longer peri
ods of time
Storage ranges from 100 MB to 10 TB
Optical disk most common media
- 5 1/4” MOD
- 2.6 GB and 5.2 GB Capacity


DLT used for longer term storage and re
dundancy
ISP module
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Storage Device (Near line)
Database
Server
RAID
MOD
SAN/NAS
DLT
HIS/RIS
Interface
(Broker)
DG
RIS
CT
W/S
M
R
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R&F
NM
PCs
CR QA
CR
Film
Digitizer
XRAY
Frame
Grabber
US
Storage Area Network
• SAN is a high-speed sub-n
etwork of shared storage d
evices
• Contains storage device (di
sk) for storing data
• SAN's architecture works in
a way that makes all storag
e devices available to all se
rvers
• Use of Fiber Channel
• High scalability for additio
nal storage and redundant
networks
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PCs
Storage devices
Network Area Storage
• NAS is a class of dedicated hard disk-based storage de
vices which provide LAN users with additional disk stor
age through a standard network connection
• In most cases, a NAS device (or NAS server) receives a
n IP address, connects to the LAN through an Ethernet
cable, and resides on the LAN as an independent netw
ork device
• Users are not demanding the server's processing time
for mundane storage tasks -- often improving the perf
ormance of local application servers
• NAS systems also include some onboard memory (RA
M) to cache network data to or from the disks
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SAN Vs NAS
• Difference between NAS and SAN is subtle
• NAS devices are big, single purpose storage ap
pliances that you plug into network
• NAS sits between your application server and
your file system
• As perform only 1 task, can serve files very fas
t
• NAS is network-centric
• SAN is a defined architecture that sits between
your file system and your underlying physical s
torage
• SAN is data-centric
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Display
HIS/RIS
Interface
(Broker)
Database
Server
RAID
MOD
DLT
Diagnostic W/S
SAN/NAS
Dedicate W/S
DG
RIS
CT
W/S
M
R
U-HealthCare System
R&F
NM
PCs
CR QA
CR
Film
Digitizer
XRAY
Frame
Grabber
US
Workstations
• Four Primary Categories
- Advanced Analysis: Used by specialists for advance
d diagnosis - 3D, volume rendering
- Diagnostic: For primary diagnosis; located in readin
g rooms; high-end 2K monitors
- Clinical: Used by clinicians and staff to consult; ICU
/ ER applications; less costly than diagnostic; 1K mo
nitors
- At Home Review: low-end; PC based; cost-effective;
review application; lossy compressed for faster trans
mit
U-HealthCare System
Standalone Vs direct PACS w/s
Standalone Workstation
Direct PACS Client
Workstation
Hard Disk Storage
Yes, varies
Minimal
Query PACS
number
All PACS system (CT, ACC,
Angio.)
Single PACS system (ACC
PACS)
Retrieval
mechanism
DICOM Q/R and association
made with different vendors
Direct attached, same vendor
Retrieval time
Slower
Faster
Diagnostic value
Depends on Monitor Grade and
Modules like MPR, 3D etc
Depends on Monitor Grade and
Modules like MPR, 3D etc
Suggested usage
1.for meeting/museum purpose
2.for single modality image
reviewing and reporting like
Radworks in U/S Rm
Direct PACS workstation for
reporting
U-HealthCare System
Web distribution






High availability, low cost
Reports / select images to referring physi
cian desktop
Point of integration with electronic patie
nt record
Lossy compression for performance
Potential for TeleRadiology
Security issues to be resolved
U-HealthCare System
RIS, HIS, ePR and PACS integra
tion
U-HealthCare System
Broker HIS/RIS and PACS interface
HIS/RIS
Interface
(Broker)
DG
RIS
CT
W/S
M
R
U-HealthCare System
R&F
NM
PCs
CR QA
CR
Film
Digitizer
XRAY
Frame
Grabber
US
Hospital Information System
• Support clinical and medical patient care
activities in the hospital
• Administer the hospital’s daily business tr
ansactions like finance, payroll etc
• Evaluate hospital performances and costs
and make long-term forecast
U-HealthCare System
Clinical System in HA, HK
• Patient Administration
•
•
•
•
In-Patient and Out-Patient Administration System
Accident & Emergency Information System
Medical Record Abstract System
Medical Record Tracking System
•
•
•
•
Laboratory Information System
Radiology Information System
Pharmacy Management System
Dietetics Catering Management System
•
•
•
•
Clinical Management System (In-Patient) Discharge Summary
Clinical Management System (Out-Patient)
Electronic Patient Records
Clinical Data Analysis and Reporting System
• Clinical Support
• Clinical Management
U-HealthCare System
Non-Clinical System in HA
Human Resources and Payroll Systems
Hospital Based Financial System
Materials Management System
Patient Billing and Revenue Collection Sy
stem
• Executive Information System
•
•
•
•
Code 9 and view codes
U-HealthCare System
Radiology Information Systems
• Similar to HIS but of smaller scale
• Interfaces to PACS based on HL7
• Department administrative management
- Scheduling and Film tracking
- Resource management and reporting
- Monitor patient status
 Link to Hospital Information System (HIS)
- Billing and Master Record
• Link to Clinical Management System (CMS)
- Prefetch for Clinical visit
- ePR integration
U-HealthCare System
Exam
Order
Exam
Scheduled
Modality Worklist
Demographics
Downloaded
RIS
RIS workflow
Web
distribution
to referring
physicians
Patient Exam
Is Performed
Images
transferred
in STS
Order
Event
Database
server
/Archive
Prefetch Exams
From Storage
PACS Worklist
Updated
Images /
Prior Reports
Dictated
status
Image migration STS to LTA
Final report
available
U-HealthCare System
Report
Verified
Exam
Read
Preliminary status
Exam
Transcribed
Broker service
DR
HA
HIS
CR
ADT
HA
RIS
HA CMS
Appt.,
X-ray reques
t
Mitra
PACS
Broker
interface
Clinical visit
US
DF
Database s
erver
U-HealthCare System
Modalities: Get WORKLIST
Get REPORT, Get INFO
Broker service
• A restricted access account will be created at S
ybase that gives limited authority for the DICO
M Broker solely for the purpose of the interfac
es
• In general, for data flow from RIS to the Broke
r, the RIS write the supported events to the ta
ble, and the Broker polls against the events ta
ble and calls the associated stored procedures
for the conversion to DICOM messages
U-HealthCare System
Broker service
• Broker main function:
- Worklist generation
- Reports storage
Registration + Post exa
m data capture (RIS)
Acc # generation + ca
ll broker for update
Need SOME time!!
Modalities query Bro
ker for worklist upda
te
U-HealthCare System
Broker poll RIS event
table and convert to D
ICOM info
ePR Architecture
• Selected images fro
m individual hospital’
s PACS are sent
• make use of the ePR
record indexing and
browsing capabilities
to read the radiology
images through CMS
workstations
U-HealthCare System
Data Flow Diagram
RIS
ePR
HA system
Appointment
Attendance
RIS operational Exam records
data
Reports (15mins)
ePR
PACS
RIS statistical d
ata
U-HealthCare System
CMS
Web Se
rver
Attendance
Data wareh
Exam & worklo
ouse
ad units (daily)
Non clinical syste
m
Characteristics of ePR
• Near instant image review
• Web distribution can be within hospital, t
o other hospitals or even private clinics
• TeleRadiography possible
• Update of patient information
• Lossy Vs lossless
• Broken pathway
• 15 minutes time lag
U-HealthCare System
Guidelines for HIS, RIS, PACS interface
• Each system remain unchanged in its con
figuration and function, only data are sha
red
• Identify the subset data to be shared an
d set up access rights/ authorization
• Convert the subset data to HL7 standard
• Define transfer protocol (TCP/IP or DICO
M)
U-HealthCare System
Typical patient and data flow
• Admission: Patient registration, notify HIS (HL7)
• Order entry/Arrival: Schedule exam and notify RIS
• Broker notified and PACS database server updated (pre
fetch)
• DICOM worklist to modality
• Exam completed: data to DICOM gateway (MPPS)
• Information/images to database/image server through
gateway (DICOM store)
• Images stored in PACS archive
• Images to workstations from PACS archive
• Dictation, transcription etc: workstation to RIS/PACS
• RIS reporting and PACS updated for reports
• Transfer: HIS/RIS to PACS, images to other PACS
• Discharge: HIS/RIS to PACS, images rub out
U-HealthCare System
Mobile PACS
U-HealthCare System
What is DICOM?
• The standard for Digital Imaging and
Communications in Medicine.
• Developed by the National Electrical Manufacturers
Association (NEMA) in conjunction with the American
College of Radiology (ACR).
• Covers most image formats for all of medicine.
• Specification for messaging and communication
between imaging machines.
U-HealthCare System
A little history
• The first version was ACR-NEMA, released in 1985.
• Its goal in developing a standard was
– To enable users to retrieve images and associated
information from digital imaging equipment in a
standard format using point-to-point connection.
– To hide differences same across multiple image
equipment manufacturers.
• To handle developing network and image standarts,
a new standard, DICOM, was proposed in 1981.
U-HealthCare System
DICOM Application Domain
LiteBox
Storage, Query/Retrieve,
Study Component
MAGN
ETOM
Print Management
Query/Retrieve
Results Management
Media Exchange
Information Management System
U-HealthCare System
Summary of DICOM Features
• NETWORK PROTOCOL
● DICOM incorporates negotiation to permit peers to
agree on the functions to be performed
• MESSAGE ENCODING
● DICOM defines 24 data types (V2.0 had 4)
● DICOM message encoding includes JPEG
compression (17 varients)
● DICOM supports multiple character repertoires
U-HealthCare System
Summary of DICOM Features
• OBJECT DATA MODEL
● DICOM is based on a completely specified data model
● DICOM includes a robust UID mechanism
• DATA DICTIONARY
● DICOM includes a large number of new data elements
• SERVICE CLASSES
● DICOM defines classes of service for specific
applications (e.g. image management, printing) and
conformance levels
U-HealthCare System
DICOM Objects
• Things such as images, reports, and patients are all objects
and are called information objects.
• Two kinds of objects in DICOM:
– Composite objects (Old objects inherited from NEMA).
– Normalized objects (New objects defined in DICOM).
• All objects and their format constitutes Data Dictionary.
• DICOM uses UIDs to identify information objects, such as
the images, reports, or transfer syntaxes.
• The form of the UID conforms to an international standard.
– 1.2.840.10008 is the root and the same for every DICOM
UID.
– Example: UID for the DICOM explicit VR little endian transfer
syntax is 1.2.840.10008.1.2.1
U-HealthCare System
DICOM Service Classes
• Composite
● Verification
● Storage
● Query/Retrieve
● Study Content Notification
• Normalized
● Patient Management
● Study Management
● Results Management
● Basic Print Management
U-HealthCare System
Hardcopy Image Reading +
Dictation/Transcription (Use Case 1)
Image Reading:
• Hardcopy Reading
• Hardcopy DICOM Print as Seen at Modality
Reporting:
• RIS-Based Transcription / Validation of Narrati
ve Report
• RIS-Based Report Storage and Management
– Send Reports
– Query Prior Reports
U-HealthCare System
Hardcopy Image Reading +
Dictation/Transcription (Use Case 1)
Report Storage
/ Mgmt.
RIS
sen
d
Narrative
Info Only
Transcription
& Correction
prin
t
Paper
print/
Mail/
Fax/Email
Electronic Report
quer
y
Acquisition
Electronic Report
Report
Repository
Validation
Film Archive
Filming
Hardcopy
Interpretation
& Dictation
U-HealthCare System
network
DICOM
optional
manual
HL7/other
Hardcopy and Softcopy Image Reading +
Dictation/Transcription (Use Case 2)
Image Reading:
•
•
•
•
Hardcopy Reading
Hardcopy DICOM Print as Seen at Modality
Softcopy Reading
Hardcopy DICOM Print as Seen During Softcopy Readin
g
Reporting:
• RIS-Based Transcription / Validation of Narrative Report
• RIS-Based Report Storage and Management
– Send Reports
– Query Prior Reports
U-HealthCare System
Hardcopy and Softcopy Image Reading +
Dictation/Transcription (Use Case 2)
stor
e
Selected
Images
Softcopy
Interpretation
& Dictation
Report Storage
/ Mgmt.
RIS
sen
d
Narrative
Info Only
Acquisition
Paper
print/
Mail/
Fax/Email
Electronic Report
quer
y
Transcription
& Correction
prin
t
Electronic Report
Report
Repository
Validation
Film Archive
Filming
Hardcopy
Interpretation
& Dictation
U-HealthCare System
network
DICOM
optional
manual
HL7/other
Acquisition Workflow Support +
Burn CD/DVD (Use Case 3)
Image Acquisition:
• RIS-based Acquisition Workflow Support (Modality Worklist)
Image Reading:
•
•
•
•
•
Hardcopy Reading
Hardcopy DICOM Print as Seen at Modality
Softcopy Reading
Hardcopy DICOM Print as Seen During Softcopy Reading
DICOM Store Images -> Burn CD/DVD
Reporting:
• RIS-Based Transcription / Validation of Narrative Report
• RIS-Based Report Storage and Management
– Send Reports
– Query Prior Reports
– Optional DICOM Store Reports -> Burn CD/DVD
U-HealthCare System
Hardcopy and Softcopy Image Reading +
Dictation/Transcription (Use Case 3)
Modality Worklist
stor
e
Selected
Images
Softcopy
Interpretation
& Dictation
Report Storage
/ Mgmt.
RIS
sen
d
Narrative
Info Only
Acquisition
Electronic Report
Paper
print/
Mail/
Fax/Email
Electronic Report
quer
y
Report
Repository
Transcription
& Correction
prin
t
Burn CD/DVD
Validation
Off-Line Archive
store
Film Archive
Hardcopy
Filming
Interpretation
U-HealthCare System
& Dictation
network
DICOM
optional
manual
HL7/other
PACS for Management of DICOM Persistent O
bjects (Use Case 4)
Image Acquisition:
• RIS-based Acquisition Workflow Support (Modality Worklist)
Image Reading:
• Hardcopy Reading
• Hardcopy DICOM Print as Seen at Modality
• Softcopy Reading
• Hardcopy DICOM Print as Seen During Softcopy Reading
• DICOM Store Images for Burning CD/DVD
• PACS-based Storage and Management of DICOM Persistent Objects
– Archive Imaging Studies
– Query Prior Imaging Studies
Reporting:
• RIS-Based Transcription / Validation of Narrative Report
• RIS-Based Report Storage and Management
– Send Reports
– Query Prior Reports
– Optional DICOM Store Reports for Burning CD/DVD
U-HealthCare System
PACS for Management of DICOM Persistent Objects (
Use Case 4)
Modality Worklist
stor
e
Selected
Images
Softcopy
Interpretation
& Dictation
Narrative
Info Only
Transcription
& Correction
sen
d
Electronic
Report
quer
y
Acquisition
Object Storage /
Mgmt.RIS
store
Validation
store
store
q/
r
Off-Line Archive
Film Archive
Hardcopy
Interpretation
U-HealthCare System
& Dictation
Filming
Paper
print/
Mail/
Fax/Email
Report
Repository
Image
Repository
PACS
prin
t
Electronic Report
Burn CD/DVD
network
DICOM
optional
manual
HL7/other