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Oncology: Radiation Therapy
“Design of the Information Architecture”
Chirag Patel
Elizabeth Accord
Joe Adams
Team Project
MMI 405
Northwestern University
May 17th, 2009
INTRODUCTION
Overview
Technology today has given us the ability to truly integrate Radiation therapy. There are
facets of the process that have the ability to be streamlined in order to provide more
efficient and safer patient care. A majority percentage of cancer patients (50 to 60
percent) have to be treated with radiation. Utilizing an integrated properly managed
system, an oncologist can not just relieve a cancer patient’s pain, but potentially cure the
cancer. The radiation destroys the cancers ability to reproduce and the body can get rid
of these cells. Radiation therapy usually is at times utilized in conjunction with other
treatments as a part of a comprehensive treatment program.
Hospital integration of a digital oncology system can truly increase levels of patient
care and quality assurance. In essence, Radiation oncology providers, particularly those
that offer newer treatment options like IMRT and IGRT, need to implement solutions that
allow them to store, recall, and compare more and larger image datasets. Sites that have
deployed digital solutions report a number of benefits. There's clearly a time savings
going into the digital age. With digital technology, they can provide more precise
treatment in the same 10 to 15 minute time slot. In addition to enhancing patient care by
enabling better treatments, digital imaging solutions also can serve as multipurpose
workflow boosters. For example, some incorporate electronic charting features that allow
physicians to shave off up to an hour of daily charting.
Objectives
Within the realm of digital oncology and radiation therapy there are many
different objectives. The goals as identified assisted in defining the structure of our
systems for the Cancer Centers of America – Western Regional Medical Center. They
essentially defined the parameters of the database and system architecture. The initial
goals are as defined below..
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Evaluate the current state environment
➢▪▪▪▪▪ Incorporate all organizational elements required to accomplish
tasks
➢▪▪▪▪▪ Analyze Standard business functions that could potentially be
streamlined via the implementation
➢▪▪▪▪▪ Create specifications for future state system via a context diagram
➢▪▪▪▪▪ Identify any current issues experienced by users
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Define system-wide architecture
➢▪▪▪▪▪ Define expectations of new system functions for future state
➢▪▪▪▪▪ Define input and output requirements
➢▪▪▪▪▪ Define data requirements
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Define functional requirements
Define performance requirements
Define system and communication requirements
Define system security requirements
Define backup and recover requirements
Identity support considerations
Define hardware requirements
Identify hardware functionality
Identify hardware characteristics
Define software requirements
Define the functionality of the software
Identify software characteristics
Define usability requirements
Define the technical requirements of the system
➢▪▪▪▪▪ Identify the requirements to develop the system
➢▪▪▪▪▪ Define the technical specifications
➢▪▪▪▪▪ Consider design constraints
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Follow up on any issues which occurred through the process.
Scope
Utilize digital imaging and fully digitized simulation, planning, and delivery of external
beam patient treatment. This will allow for
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Increased tumor isolation and effective treatment to improve patient outcomes.
Reduced set-up error.
Reduced volume of healthy tissue adjacent to the target that is required to be
irradiated.
● Accurate treatment documentation and transmission.
Glossary
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EPID (Electronic Portal Image Device) system, which can replace conventional
film/screen systems to verify patient position.
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DICOM RT Objects
·
RT Structure Set, containing information related to patient
anatomy, for example structures, markers, and isocenters. These entities
are typically identified on devices such as CT scanners, physical or
virtual simulation workstations, or treatment planning systems.
·
RT Plan, containing geometric and dosimetric data specifying a
course of external beam and/or brachytherapy treatment, for example
beam angles, collimator openings, beam modifiers, and brachytherapy
channel and source specifications. The RT Plan entity may be created by
a simulation workstation, and subsequently enriched by a treatment
planning system before being passed on to a record and verify system or
treatment device. An instance of the RT Plan object usually references a
RT Structure Set instance to define a coordinate system and set of patient
structures.
·
RT Image, specifying radiotherapy images which have been
obtained on a conical imaging geometry, such as those found on
conventional simulators and portal imaging devices. It can also be used
for calculated images using the same geometry, such as digitally
reconstructed radiographs (DRRs).
·
RT Dose, containing dose data generated by a treatment planning
system in one or more of several formats: three-dimensional dose data,
isodose curves, DVHs, or dose points (NEMA, n.d.)
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Linear accelerator - A machine that creates high-energy radiation to treat cancers,
using electricity to form a stream of fast-moving subatomic particles. Also called
mega-voltage (MeV) linear accelerator or a linac.
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Simulation - A process involving special x-ray pictures that are used to plan
radiation treatment so that the area to be treated is precisely located and marked.
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X-rays - High-energy radiation used in low doses to diagnose disease or injury
and, in high doses, to treat cancer.
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Dosimetrist - (do-SIM-uh-trist) A person who plans and calculates the proper
radiation dose for treatment.
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External radiation - Radiation therapy that uses a machine located outside of the
body to aim high-energy rays at cancer cells.
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Cancer - A term for diseases in which abnormal cells divide without control.
Cancer cells can invade nearby tissue and can spread through the bloodstream and
lymphatic system to other parts of the body.
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Oncology - The study of tumors.
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Intensity modulated radiation therapy or IMRT - IMRT is a specialized form of
external beam therapy that allows radiation to be shaped to fit specific tumor.
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Image-Guided Radiation Therapy or IGRT - IGRT is a technique that precisely
determines the location of tumors just prior to treatment on a daily basis.
Current Environment
Cancer Treatment Centers of America at Western Regional Medical Centers
“People living with cancer in the Western United States now have a new place to call
home. On December 29, 2008, a fourth Cancer Treatment Centers of America (CTCA)
hospital opened its doors. Western Regional Medical Center in Goodyear, Arizona (near
Phoenix) provides patients and caregivers in the West easier access to the unique care
model of the Cancer Treatment Centers of America (CTCA 1).”
At Cancer Treatment Centers of America at Western Regional Medical Center, We have
radiology oncology, medical oncology, surgery oncology, infusion and inpatient all under
one roof. Also we provide nutrition, naturopathic medicine, and counseling. There are
over 200 employees at the facility. The center will off the latest medical treatment
options to treat cancer combined with a full array of complementary therapies to mitigate
side effects and heal the whole person.
The following services are an intricate part of the facility: medical oncology, surgical
oncology, radiation oncology, naturopathic medicine, imaging, nursing, food services,
housekeeping, bio-medical equipment maintenance, plant operations and engineering,
security, laboratory, naturopathic medicine, mind-body medicine, materials management,
respiratory therapy, rehabilitation, accounting, accounts payable, registration, charge
coordination, compliance, marketing, public relations, oncology information specialists,
quality services, employee health, infection control, safety, risk, operational compliance,
guest/patient relations, administration, human resource and internal medicine.
The centers practice of Patient Empowerment Medicine (PEM) puts patients first and
places them at the center of their care program. This is there the Centers excellent cancer
treatment begins. With that in mind, one can better understand the utilization of The
Mother Standard for patient care. CTCA goes above and beyond by asking, if your
mother (or other loved-one) had cancer, how would you want her (her/him) to be
treated? What is the best quality of care and service?
At CTCA it’s called it The Mother Standard. The philosophy underlies the business
model and is a key factor in their success. PEM, as it pertains to the Mother Standard,
works within the patient’s schedule (not the provider’s) and CTCA has successfully
recruited physicians and other care providers who work as an integrated team to support
these initiatives. As a fundamental element of its model, CTCA does not depend on the
usual physician referral paradigm. Instead, it uses sophisticated national and regional
marketing programs that include broadcast, print, radio, and affinity group techniques to
attract its patients.
These marketing activities target all patients who have a fighting spirit, and are willing to
go wherever they need to go, and do whatever they need to do to pursue victory in their
fight against cancer. CTCA provides comprehensive, integrative care in a healing
environment of support and compassion designed to help patients and their families
reduce stress, empower their immune systems, and focus solely on the healing process.
CTCA is the leader in patient-centered oncology care and expects to remain on the
leading edge of cancer treatment through aggressive, innovative and novel techniques,
technology and therapies. Moreover, CTCA’s clinical research is now, and will continue
to be, applied in a timely manner to benefit patients.
The logistical layout of the technical components of the facility consists of the 1st floor
where there are two core rooms at opposite ends of the building for equipment required in
order to support an all-digital facility. In the IDF rooms there will be network racks. The
rooms are 18’ by 30’ and 9.5’ by 31’ with four - 4” conduits that connect to separate
power grids from the outside wall. The rooms were designed to be on opposite external
walls in order for risk mitigation and to run conduit and electrical service into the rooms
with ease of access. If one goes down, the entire hospital can be run off of one core
room. On the second floor there is one closet in the inpatient nursing unit and one closet
in the internal medicine department. There are a total of two core rooms and two
communication closets on the first floor and two communication closets on the second
floor.
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Facility is “paperless” and wireless with desktop, bedside, and hand-held hardware
throughout.
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Diagnostic, analytical, and procedural equipment are new, state-of-the-art.
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Information Technology hubs are located on opposite (north and south) sides of the
First Floor to provide 100% redundancy in the event either hub is compromised.
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Cable trays are organized along main corridors to provide organized distribution
throughout facility and to facilitate easy access for maintenance.
3
3.1
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3.2
Requirements Overview.
Goals.
Utilize digital imaging and fully digitized simulation, planning, and
delivery of external beam patient treatment. This will allow for
Increased tumor isolation and effective treatment to improve patient outcomes.
Reduced set-up error.
Reduced volume of healthy tissue adjacent to the target that is required to be
irradiated.
Accurate treatment documentation and transmission.
Input and Output Requirements.
Oncology Information System
Input
Patient registration, demographic information, diagnosis, staging,
and medical oncology charting from HIS.
Pharmacy, laboratory, pathology, and radiology
reports/information.
Treatment record from record and verify system.
Output to HIS
Treatment plans management and machine scheduling
Relative value units, workload, and custom codes;
Cost/charge information
Imaging Modality
Input from Radiology Information System
Patient demographics using DICOM Modality Worklist standard.
Output
DICOM Image Set.
Virtual Simulation Application
Input from Imaging Modality
DICOM Image Set.
Output
RT Structure Set object is produced, containing identified
structures such as the tumor and critical organs. An associated RT
Plan is also created, containing beam geometry information.
Digitally-reconstructed radiographs (DRRs) may also be created as
RT Image objects (NEMA, n.d.).
Treatment Planning System
.
Input
DICOM Image Set.
RT Structure Set.
RT Plan.
(DRRs)
Output
Calculates dosimetry data for the plan. A new RT Plan object is
created, and RT Image DRRs may also be produced.
Record and Verify System
Input
RT Plan
(DRRs)
Output
Initialize a Linear Accelerator (linac) treatment. Alternatively,
the LINAC itself could make use of the object directly. An EPID can create RT
Image
verification images, or compare acquired images with DRRs
created by the above steps (NEMA, n.d.).
Periodically during the course of treatment, the linac or record
and verify system creates Treatment Record objects, generally one for each
treatment
session. (NEMA, n.d.)
3.3
Data Requirements.
DICOM 3.0 for image data transfer using NEMA standards.
DICOM RT for planning and treatment messaging.
HL7 for information exchange amongst Oncology Information System and
other systems (HIS, LIS, RIS, etc.)
3.4
Functional Requirements.
See hardware and software functionality below.
3.5
Performance Requirements.
Electronic charting features that allow physicians to reduce charting
duration.
Create workflow efficiencies.
Increase tumor isolation and effective treatment.
Reduce the set-up error and the volume of healthy tissue adjacent to the
target that is required to be irradiated.
Provide accurate treatment documentation.
Facilitate accurate billing.
3.6
Systems and Communication Requirements.
Oncology Information System
Imaging Modality (CT, MRI, etc.)
Virtual Simulation Application
Treatment Planing System
Record and Verify system
DICOM, DICOM RT, HL7
3.7
System Security Requirements.
Commensurate with ISO 18308.
3.8
Back up and Recovery Requirements.
It should be possible to restore multiple systems (applications, databases,
operating system platforms) to the same point in time.
Remote backup systems, off-site storage, and vaults / archives should be
manageable by the backup solution.
Business-defined recovery point objective (RPO), maintenance point
objective (MPO), and recovery time objective (RTO) metrics, and most
other business requirements for continuity of operations, should be met
through the backup and recovery solution.
Other key metrics that should show improvement with robust backup and
recovery include: time to backup (measured for each storage tier,
technology, server type, application, and database type), time to restore
(measured similarly), number of support calls relating to backup or
recovery issues, percentage of time that systems problems lead to data
loss, percentage of time that systems problems lead outages, average
downtime per month, and percentage of IT time spend conducting backup
and restore operations (Levine, 2008).
3.9
Support Considerations.
In-house IT support 24X7.
In-house biomedical engineering support during normal business hours.
Vendor Help Desk available via telephone weekdays during normal
business hours. After-hours and weekend calls will be returned the next
business day.
Vendor field service engineer support within one-hour travel radius.
3.10
Hardware Requirements
Color Laser Printer and Stand for treatment planning.
Standard Workstation: single processor, modem, and flat panel monitor for physician
use and desktops.
Workstations for:
● Patient Self Check-In
● Receptionist
● Physicists
● Dosimetrists
● Administrators
● Nurses
● Physicians
● Tumor Registrar
Each treatment room needs:
● Compatible workstation
● In-room monitor with mounting hardware
● laser printer
Each simulator room needs:
● Compatible workstation
System administration needs:
● workstations or Citrix compatible windows terminals
Radiation Oncology Database Server Requirements (5U Rack Mounted -- Upgrades)
Processor: Dual [Single or Multi] Core Intel® Xeon Processor 1MB (or greater) L2
Cache, 2.0GHz, 800 MHz or 1333MHz FSB
Bus Type: PCI/PCI-E
Memory (DRAM): 4 GB Fully Buffered DIMM's, Dual Ranked, ECC
Hard Drives: 4x146 GB Hot Swap drives with Ultra-320 SCSI interface (includes online
spare). Drive should have < 10ms access times at 15K RPM. Effective disk space 292
GB.
Drive Controller: Dual channel Ultra-320 Configurable SCSI array controller with >
128MB cache. Configured for hardware RAID 5 fault tolerance and (50/50) read/write
cache (Software RAID not recommended/supported). CD and LTO tape unit should
operate from separate controller or channel 2 of SCSI controller.
Floppy Disk: 3.5" drive, 1.44 MB
Optical Drive (CD/DVD): Multi-session 24X or greater with SCSI or IDE interface
Backup Tape: LTO-2 200/400 GB, SCSI interface, internal drive unit, and BrightStor™
ARCserve® 2000 or later.
Network Interface:
1 LOM 10/100/1000Mbps, compatible with the network operating system and cabling.
Redundancy: PSU and Fans
Ports: 1 serial, minimum 2 USB
Operating System: Microsoft® Windows® Server 2003 R2 (Standard or Enterprise) with
Service Pack 2 (25 client access license or sufficient seat licenses).
File System: NTFS
Microsoft® OS Architecture 32-bit (not 64-bit)
Microsoft® .NET Framework
42U Half Height Rack systems come with the following components (see notes below):
● Cables for Keyboard and Video
● NEMA standard power strip
● 1U 8-port keyboard/monitor KVM switch box
● 1U keyboard/trackball and monitor console
● 2U 3000VA Uninterruptible Power Supply (UPS)
● 24-port patch panel (CAT5E)
Scanner: integration of external medical records.
HL7 Server Requirements
Processor: Dual Intel® Xeon® 5130 Dual Core Processors at 2.0 GHz, 1333MHz FSB
with 4 MB cache.
Memory: 4 GB RAM
Hard Drives: 2x300 GB (OS/APP) Hot Swap drives with Serial Attached SCSI interface
at 10000 RPM
Drive Controller: Single channel SAS RAID controller.
CD-ROM/DVD: CD Reader or DVD reader.
Network Adapter: 1 Ethernet NIC 100/1000 Mbps.
Redundancy: PSU and Fans
Ports: minimum 2 USB
Microsoft® Windows® 2003 Server Standard Edition, Service Pack 1
3.11 Hardware Functionality
Hardware used must be approved based on the current Microsoft® specifications. 1
Gbps network recommended for maximum speed and performance. If the customer is
providing a filtered data feed, one HL7 server can support up to about 150 concurrent
users. If there is a substantial amount of filtering required, fewer concurrent users may be
supported on one interface engine. Another parameter to evaluate is the number of
messages per day. If there is a need to parse in excess of about 50,000 messages per day,
additional servers may be needed.
3.12 Hardware Characteristics
Hardware used should be approved based on the current Microsoft® Windows® Catalog
Listing. In addition to the Database Server an image fileserver is required for use with all
image-based products and would be installed in the same rack. A 1 Gbps network
recommended for maximum speed and performance. The Operating System (build and
version) on the Database Server shall match the Operating System (build and version) on
the alternate server.
It is recommended that windows-compatible 600 DPI or greater laser printers be utilized
for the printing of treatment planning, dosing and imaging information. Printers utilized
for printing images should have a high-quality dye-sublimation to produce B/W or color
images with color overlays on both paper and transparencies.
3.13 Software Requirements
DICOM 3.0 CT/MR Image Import Server License
DICOM RT Server License
RTOG DICOM Export
DICOM Print
DICOM RT
1. RT objects supported include: RT image, RT Structure, RT Plan, RT Dose, RT
Treatment Record, RT Treatment Summary;
2. Diagnostic image modality support;
3. DICOM Query/Retrieve provides image data transfer using NEMA standards;
4. DICOM RT Storage; and
5. Import/Export of image file formats: CART (Computer Aided Radiotherapy),
PortalVision Mark 1, BMP (Bitmap), TIFF (Tag Image File Format), Vision file and Raw
Pixel Data.
Must have Windows XP operating systems
Local Area Network (1 Gb recommended, 100 Mb required)
Networked environment
Compatible server hardware
Internet access for remote monitoring and support via Smart Connect;
Windows 2000 or 2003 operating system installed on server;
3.14
Software Functionality.
The treatment planning software is implemented in such a way that DICOM CT
formatted image data can be transferred directly to the system. The CT images are
automatically segmented and made available for subsequent DICOM transfer to treatment
planning and management systems. This software can also be used for on-demand image
segmentation during the treatment planning process via DICOM image file transfer
between the requesting software and the software.
The system database is the core component of the information system. The relational
database serves as the repository for patient information and images imported to or
captured by the database. Included with the database are archive/restore and system
administration.
1. Includes the Archive application for the archival/restoring of patient records in cases of
storage constraints;
2. Includes a separate environment for testing interfaces, applications, system
configurations and data migration;
3. Includes the data administration application(s) used to configure the system
4. Includes user rights and license administration;
5. Uses Open Client and Sybase 12.5 for multi-access to database;
6. Based on client/server architecture for fast data access capability;
7. Full logging and data integrity protection;
8. Transaction logging configurable; and
9. Remote monitoring and service support.
The Registration System must interface with HIS to pull patient registration,
demographic information, diagnosis, staging, and medical oncology charting from the
HIS. Treatment plan management and machine scheduling must be pushed back to the
HIS via HL7 from the integrated radiation system.
The interfaced HIS system must also include activity management for resources across
multiple departments and hospitals, task management designed to assist in streamlining
workflow, care path management tracking all patient activity throughout
hospitals/departments and inter-departmental messaging via secure health messaging
interfaced with HIS.
The Radiation system must push the following to the HIS:
o relative value units, workload, and custom codes in order to capture
associated costs and productivity activity information;
o cost/charge information for completed services or clinical activities
based on scheduled tasks and appointments;
o supports credits for previously exported activities to aid in keeping a current
charge capture record; and
o exports captured activity information to hospital or private billing systems.
The following activities will be completed in the HIS and interface to the medical record
portion of the integrated treatment planning system in order to create one radiation record
per Joint Commission requirements.
o Medical, family and social histories, education and counseling,
medication, prescription and allergies with favorites lists;
o Review of Systems and Physical Exam assessments;
o Assessments of toxicities based on standard tables such as NCI and RTOG;
o Documentation of Vitals Signs and Lab Results;
o Assessment of performance status based on standard tables (Karnofsky,
Lansky, ECOG);
o Prescriptions;
o Audit tracking by operator, date and signature; and
o Nursing, progress and assessment notes and graphical
displays.
In order to maintain a comprehensive record, the system must also accommodate the
scanning and importing of records from external facilities and the electronic sign-off that
said medical records were considered during treatment planning.
Software will create, import, scan, fax, email, or print information from the patient's HER
have the functionality to view and approve all pending patients' documents, create
customized templates and documents to auto-populate selected fields with information
from the radiation information system database and HIS database or enter free text
and have the capability for hyperlinks (Navigation tags) that auto-populate
documentation using selected functional areas from within the database; and access to the
full database via software installed on workstations. Image approval and status changes
with messaging back to Treatment will occur in the Radiation Information System.
3.15 Software Characteristics
Base treatment planning software which includes multi-modality image support, image
registration and blending, clinical protocols, advanced segmentation, virtual simulation,
beam placement, plan evaluation, electronic plan approval, electronic chart and
configurable printing of plan documentation. 2D and 3D dose calculation on a
distributed calculation framework including beam configuration, IRREG, 3D conformal
and field in field planning using Anisotropic Analytical Algorithm (AAA) or pencil beam
convolution, and electron calculation using Generalized Gaussian Pencil Beam 2D
BrachyVision for film based brachytherapy planning, IMRT Planning package including
beam angle optimization, interactive IMRT optimization, electronic surface
compensation and planar compensation. Support either split carriages or large-field
IMRT. Also contains leaf motion calculation software for multiple-static-segment
delivery on a Linear Accelerator.
A database with interface is intended to provide basic connectivity testing to a Hospital
Information System or third party treatment planning system. The basic system includes
chart QA, offline review, outlook sync for scheduling, data segmentation, long term
archive and DICOM RT. This software is intended to also support connectivity to
medical oncology products and tumor registry products. It uses Open Client and Sybase
12.5 for multi-access to database.
3.16
Usability Requirements
Base treatment planning software must include multi-modality image support, image
registration, clinical protocols, advanced segmentation, virtual simulation, beam
placement, plan evaluation, electronic plan approval, and electronic chart on the
physician’s desktop and accessible at other workstations.
The database with interface will be interfaced via HL7 to push progress notes, dosing
information and length of treatment from the treatment planning system, consult notes,
H&P’s and areas being radiated to the Hospital Information system. All of this
information must be accessible to scheduling, medical oncology, surgical oncology,
pharmacy and nursing.
Information must be easily readable and accessible and interface must appear seamless to
the physician. Interface should be continuous and should not require any manual push of
information on the part of the user. Users must be able to view multi-modality diagnostic
images simultaneously, folder there must be image enhancement tools for more flexibility
in visualizing critical structures, including image contrast/brightness/sharpness
adjustments, color maps, zoom/pan/rotate/flip, image annotation, and region of
interest. There must also be image analysis tools for more precise patient positioning
including measurements line/area/histogram of pixel values, cine, image blending for
reference and Portal images. Usability requirements also include single sign-on for ease
of access for clinicians.
4 Technical Requirements.
4.1
Development Requirements.
Vendor supplied meeting FDA 510(k) Clearance.
4.2
Technical Specifications.
Technical specifications are given in detail in section 3.10 and 3.14. Please refer to
these sections.
4.3
Design Constraints.
Vendor supplied meeting FDA 510(k) Clearance.
5 Problems and Resolution.
Increased quality of patient care is realized through a fully digital oncology suite. Image
Guided Radiation Therapy addresses an important clinical challenge. It is inneficient to
position a patient for treatment based soley on marks or tattoos on external anatomy. Both
patient motion and tumor changes not only cause difficulties in tumor isolation, but also
normal tissue is unnecessarily iradiated. This is especially concerning when tumors sit close
to sensitive tissue. Utilizing IGRT, therapists and physicians know exactly where a tumor is
and which tissue to iradiate. This digital systam also allows concise treatment
documentation to be transmitted to the electronic medical record. Reduced manual
charting, accurate billing, and further workflow efficiencies are realized. These pieces
combine to provide optimal patient care, and ultimately improved outcomes.
REFERENCES
NEMA (n.d.). DICOM IN RADIOTHERAPY. Retrieved May 16, 2009 from
http://medical.nema.org/Dicom/Geninfo/brochure/RTAAPM.HTM
Levine, R. (2008). Backup and recovery techniques. Retrieved May 24, 2009 from
http://wikibon.org/?c=wiki&m=v&title=Backup_and_recovery_techniques
American College of Radiology. “About Us.” Nov 15th,
2007. http://www.acr.org/s_acr/sec.asp?CID=2561&DID=17606
Radiation Oncology. Glossary. Retrieved May 25th 2009 from
http://www.fahc.org/Radiation_Oncology/glossary.html
St. Vincent Health Center. Cancer Services Retrieved May 23rd 2009 from
http://www.stvincent.org/ourservices/oncology/resources/glossary.htm