 The
HDR 1000 Plus Well Chamber, SeeDOS Code 90008, precisely calibrates radioactive sources used for cancer treatment. The HDR 1000 Plus is the standard instrument for independently verifying prescribed patient dose. The verification helps protect the hospital from misadministration and liability. The HDR 1000 Plus is an air communicating chamber so there is no inaccuracy due to
an undetected gas leak as in a pressurized chamber. Performance of the HDR 1000 Plus has been validated in over 30 publications.
The HDR 1000 Plus is ideal for low dose rate and high dose rate brachytherapy. Source holders are available for most existing isotopes available on the market today. If we do not list a source holder for the isotope you wish to measure, contact us and we will develop one for you. |
Go to "Purchase justification for well chamber"
Go to " HDR1000 Brachytherapy Well Camber Recalibration and upgrade"
Go to " Long Term Stability of HDR1000 Well Chamber"
For a detailed brochure on the HDR1000 plus well chamber and Max4000 electrometer please click here
(pdf file)
NEW (End of January 2003)HDR1000 Well Chamber Brachytherapy Source Calibration pdf Brochure - showing available inserts
NEW (February 2003) New Brachytherapy source measuring and handling systems pdf
For an Acrobat Reader to read the pdf file please click on the adjacent Acrobat logo 
Advantages of the HDR 1000 Plus Ion Chamber
Easy to use: No complicated set-up or lengthy procedure.
Stable: Short term stability, within +/-0.02% for ten insertions. One to two year re-calibrations average within 0.2% of original calibration.
Confidence: Corrections are built in, requiring only the application of the ADCL calibration factor.
Aion: Ion collection efficiency is 1.000 with sources ranging from 0.1 mCi to greater than 20 Ci. If you have a different chamber with a lower collecting efficiency the response is not linear at activities other than the calibration point, and your accuracy may suffer.
Response: 0.1% over 1cm (+/-5mm about center)
Isotropic: No problems with inhomogeneities in sources.
Validated: Operation of the HDR 1000 Plus is described in nineteen publications clearly demonstrating the superior performance of the HDR 1000 Plus Well Chamber.
Versatile: Can be used with any standard electrometer.
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Quality Assurance Tests
A new Quality Assurance Tool has been designed for the HDR 1000 Plus Well Chamber which performs the following crucial tests:
- Source positioning verification to 0.3mm
- Timer accuracy
- Consistency of source activity
- Fast, 10-15 minute procedure2
- No films and development procedures
- No multiple distance estimates
The Quality Assurance Tool tightly collimates the radiation received by the HDR 1000 Plus Well Chamber to a narrow plane. Three short measurements are taken as the Iridium-192 source is advanced to the 4mm opening. These measurements provide the information for (1) source positioning verification; (2) timer accuracy; (3) consistency of source activity.
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A constant, K, is determined with formulas outlined in the instructions. If all the determinants of K remain within 1%, the user can be assured that the source position has remained constant to within 0.3mm, the source activity calibration has remained constant to within 0.01Ci, and the error in dwell time is less than 0.1 second.
SPECIFICATIONS
| ADCL Calibrations: |
HDR 192Ir and/or LDR radionuclides as requested
| | Active Volume: |
245 cm3 (122mm x 4.6mm x 1.75mm)
| | Isotope Source Holder: |
2.2mm I.D. (standard), Optional inserts available
| | Connector: |
Two lug triax (standard), TNC, Type M, or BNC + Banana (optional)
| | Range: |
0.1mCi to 20mCi
| | Cable |
1 meter (3 feet)
| | Bias Voltage Applied: |
+/-300 volts
| | Leakage: |
Less than 5x10-14
| | Stability: |
0.2% (Reproducibility)
| | Response: |
+/-0.5% over 25mm at center of axis
|
Sensitivity:
Source:
| |
HDR Iridium:
| |
Caesium:
| |
LDR Iridium:
| |
Iodine:
| |
Palladium:
|
| | Current to Apparent Activity | Current to Air Kerma Strength U=1uGym2/h | |
8.6 nA/Ci
|
2.1 pA/U
| |
5.6 nA/Ci
|
2.0 pA/U
| |
9.1 nA/Ci
|
2.3 pA/U
| |
5.4 nA/Ci
|
4.3 pA/U
| |
2.4 nA/Ci
|
2.1 pA/U
|
| | Aion |
0.9996
| | Case: |
Wooden carrying case
| | Dimensions: |
| | Height: |
15.6 cm (6.1 inches)
| | Diameter: |
10.2 cm (4 inches)
| | Insert Diameter: |
3.5 cm (1.4 inches)
| | Insert Height: |
12.1 cm (4.8 inches)
| | Weight: |
2.7 kg (6.1 lbs)
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PURCHASE JUSTIFICATION FOR A WELL CHAMBER
HDR 1000 Plus Brachytherapy Well Chamber, SeeDOS Code 90008
What is it?
The HDR 1000 Plus Brachytherapy Well Chamber is a precise measuring instrument used for accurate calibration of radioactive sources in cancer treatment. The HDR 1000 Plus is the standard to independently verify the precision and accuracy of the prescribed dose patients receive from radioactive isotopes. This verification protects the hospital from liability and
misadministration.
Why is it needed?
The former policy of relying on the manufacturer's calibration is no longer adequate. It is now recommended by various groups (ICRP, AAPM, ABS, ACR, COMS) that each institution compare the manufacturer's stated value with accurate measurements using appropriately calibrated equipment.1 Use of radionuclides without in-house verification of source strength is not advisable
due to the accuracy required for maximizing tumour cell death and minimizing healthy tissue damage.2,3
" Well-type ionization chambers make it easy to establish source calibrations with NIST traceability. Thus, for sources for which NIST provides calibration it is no longer necessary and should no longer be a practice to rely on source strengths quoted by the manufacturer."4
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In the USA , ACR Standards for Brachytherapy Physics requires a well chamber be used in order for an institution to be accredited.5 Some NRC agreement states have ratified a mandate that a well chamber be used for independent calibration of interstitial brachytherapy applications.
Task Group 56 (USA) lists a calibrated well chamber and electrometer as instrumentation that is needed for any and all brachytherapy procedures.4 It is clear that this equipment is no longer an option for all brachytherapy physics programs.
The well chamber is the recommended standard for HDR Iridium calibrations as well. "Each HDR facility should acquire a suitable re-entrant chamber. The external beam ion chamber is an acceptable but not a recommended alternative."4
Dose calibrators typically used in nuclear medicine departments cannot be used for calibration of iodine or palladium seeds as the reading received will not be an accurate measurement. The problem is not the low activity, but low energy of iodine and palladium (28KeV, 22KeV) which do not adequately penetrate the thick walls of a dose calibrator. The nuclear medicine
dose calibrator is optimized for reading Tc-99 which has an energy of 140 KeV and cannot adequately read energy levels as low as 28KeV.
Monitoring Source Activity
Brachytherapy sources are assigned a calibration by the manufacturer. For example, for LDR Iodine the manufacturers stated calibration accuracy is only +/-5% random uncertainty of the mean output with a 7% uncertainty spread in each range.6 This means there could be a discrepancy in stated activity and the true value of your sources. Many manufacturers of
brachytherapy seeds, including Amersham, recommend independent verification of their sources.6 "Every institution practicing brachytherapy shall have a system for measuring source strength with secondary traceability for all source types used in its practice. Prior to using newly received sources for treatment, the vendor-supplied calibrations must be verified as per Task Group No. 40
recommendations. The institution should compare the manufacturer's stated value with the institutions standard."4
Task Group 40 (USA) of the AAPM Radiation Therapy Committee recommends a tolerance of 3% for agreement between the institutional assay and the vendor's statement of source strength. The common experience has increasingly been a significant number of shipments found outside the recommended 3% tolerance.7 Without independent verification of your source strength this variance
would not be discovered. These findings require that independent verification of the vendors stated value be performed.
References
1. Comprehensive QA for radiation oncology: Report of AAPM Radiation Therapy Committee Task Group 40. Med. Phys. 21(4):581-618, 1994. "However, it is the responsibility of the institution to verify that this (manufacturer's) calibration is correct. The institution should compare the manufacturer's stated value with the institution's standard."
2. A New Re-Entrant Ionization Chamber for the Calibration of... : Goetsch, Attix, DeWerd, Thomadsen. Int. Journal Radiation Oncology Biol. Phys. Vol. 24. pp. 167-170, 1991 " The manufacturer provides an activity calibration for each source with a stated accuracy of +/- 10%. No traceability of this calibration to any national standards laboratory has been demonstrated. Since the
International Commission on Radiation Units and measurements has recommended an overall uncertainty of no more than +\-5% in absorbed dose delivered to the treatment volume, the manufacturer's calibration is not considered adequate by most institutions."
3. Physics: Calibration and Quality Assurance; Ezell, Hicks, and DeWerd, 7th International Brachytherapy Working Conference. 1992. "Calibration of all sources is necessary because some sources are delivered from the source manufacturer with +10% specification, One facilities experience has shown a variation of 15% in delivered sources."
4. Code of practice for brachytherapy physics: Report of AAPM Radiation Therapy Committee Task Group No. 56. Med. Phys. 24(10), : 1568-1569, 1582, 1594-1595, Oct. 1997. " Well-type ionization chambers make it easy to establish source calibrations with NIST traceability. Thus, for sources for which NIST provides calibration it is no longer necessary and should no longer be a
practice to rely on source strengths quoted by the manufacturer."
5. ACR Standard for Brachytherapy Physics: Manually Loaded Sources. Res. 25, 1995. "Each facility should have instrumentation to independently verify the source strength provided by the manufacturer. This should be done with a well ionization chamber with a calibration directly traceable to NIST."
6. AMERSHAM product literature: 1997. "It is recommended that customers measure each source to validate the values stated on the (vendors) Test Report, prior to the sources being implanted into patients."
7. Experience with Assays of 125I Seeds;
Johnson, and Kline. Med. Phys. 24 (6): pg. 1019, June 1997. " A significant
number of shipments have been outside the recommended 3% tolerance. Our
supposition is that there has developed a systematic error in the
calibration or "binning" system employed by the vendor. Also, based on our
experience, the tolerance recommended by the RTC TG-40 must be considered unreasonable for 125I seeds.
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HDR 1000A BRACHYTHERAPY WELL CHAMBER RECALIBRATION AND UPGRADE PROGRAM
Option One : Re-Calibration , SeeDOS Code 91004
Send your HDR 1000 Plus Brachytherapy Well Chamber to SeeDOS Ltd. We will facilitate your HDR 192Ir re-calibration by the Accredited Dosimetry Calibration Laboratory - University of Wisconsin for the same price as you would pay the ADCL directly. Your HDR 1000 Brachytherapy Well Chamber will also be examined to
assure its integrity.
SeeDOS will include a six month extended warranty effective from the time of re-calibration.
Option Two : HDR 1000 Plus Upgrade Option, SeeDOS Code 91008 - for Increased Sensitivity
If you have the older version HDR 1000 Well Chamber, SeeDOS will upgrade your HDR 1000 to the new HDR 1000 Plus design. The HDR 1000 Plus has a much less attenuating window which makes the HDR 1000 Plus 30% more sensitive than the HDR 1000 for iodine seed and palladium seed measurements. This upgrade would be important to obtain if your facility may be
treating patients with the Amersham 6711 iodine seeds, or palladium seeds for prostate cancer. The HDR 1000 you currently have is not quite sensitive enough for the 6711 iodine seed and palladium seeds typically used for prostate cancer treatment.
Note : As this upgrade will invalidate current calibrations it is best to obtain this upgrade when your HDR 1000 needs re-calibration.
Note : If
you currently have an HDR 1000 source holder for caesium, SeeDOS Code 70005, it must also be upgraded to Source Holder, SeeDOS Code 70020 when you obtain the upgrade to the HDR 1000 Plus.
When you return your HDR 1000 for an HDR 192Ir re-calibration, it would be an excellent time to obtain this upgrade and add inserts and calibrations for low dose rate isotopes.
Additional Source Holders Available for the HDR 1000 Plus
This table is provided for your convenience in identifing the proper Source Holder for use with the Seeds and Wires utilized by your facility.
| |
Item Number |
Standard Imaging's Source Holders |
Isotopes for Holder |
ADCL Calibrations Available |
 |
70010 |
Source Holder for HDR Iridium
2.2 mm Opening |
HDR Iridium |
80010 HDR Iridium |
 |
70008 |
Quality Assurance Tool Insert
User Manual |
HDR Iridium |
None |
 |
70020 |
Source Holder for Caesium
5 mm Opening |
Caesium |
80020 Caesium |
 |
70003 |
Source Holder for Caesium Remote
Afterloading 7.1 mm Opening |
Caesium |
80020 Caesium |
 |
70009 |
Source Holder for LDR Iridium Ribbons |
LDR Iridium |
80025-A LDR Iridium, Alpha Omega Services
80025-B Iridium, Best International |
 |
70016 |
Source Holder for Single LDR Seeds
1.2 mm Opening |
LDR Iridium |
80025-A LDR Iridium, Alpha Omega Services
80025-B Iridium, Best International |
| Iodine |
80040-A Nycomed Amersham 6702 OncoSeed™
80040-B Nycomed Amersham 6711 RAPID Strand™
80040-C North American Scientific IoGold
80040-D Best Industries 2301
80040-E Bebig / Uromed Symmetra
80040-F Mills Biopharmaceuticals 125
80040-H Iodine, International Isotopes SH
80040-I Implant Sciences
80040-J International Brachytherapy
80040-K Source Tech
80040-L DRAXIMAGE, Inc.
80040-M Nucletron selectSeed I-125™
80040-N Nycomed Amersham 6733 EchoSeed™
80040-O Advantage I-125™, IsoAid |
| Palladium |
80035-A Palladium, North American Scientific Pd Gold
80035-B Palladium, Theragenics
80035-C Palladium, Best Medical International
80035-D Palladium, IBT/Int. Brachytherapy |
 |
70022 |
Source Holder for LDR Seed Batch Assay |
Iodine
|
None
|
| Palladium |
None |
 |
70023 |
Source Holder for I-125 RAPID® Strand Seeds |
Iodine |
None |
 |
70024 |
Source Holder for Mick® Cartridge |
Iodine |
None |
| Palladium |
None |
|
70022 |
Source Holder for LDR Iridium Wire Coil |
Irdium Wire |
None |
 |
70026 |
Source Holder for 5 cc and 10 cc Syringes |
Metastron® |
None |
| Samarium |
None |
 |
70032 |
Source Holder for Bard EXPRESS Seeding Cartridge |
Palladium |
None |
NOTE: One source holder may have several calibrations associated with it. For example, a Source Holder for Single LDR Seeds REF 70016 may have calibrations for Iodine, Palladium, and LDR Iridium.
|
SeeDOS Source Holder Code |
Description of source holder Please click on SeeDOS Source Holder Code to go to detailed descriptions and illustrations | |
70003 |
Source Holder for Caesium Remote Afterloading, 7.1 mm opening | |
70008 |
Quality Assurance Tool Insert
| |
70009 |
Source Holder for Low Dose Rate Iridium Ribbons
| |
70010 |
Source Holder for HDR Iridium, 2.2 mm opening | |
70016
|
Source Holder for Individual Iodine, Iridium, or Palladium Seeds
| |
70020
|
Source Holder for Caesium. This replaces P/N 70005 which will not work with the HDR 1000 Plus Brachytherapy Well Chamber. A trade in is available, P/N 70020U.
| |
70022
|
Source Holder for LDR Seed Batch Assay
| |
70023
|
Source Holder for Measurement of RAPID StrandTM Iodine Seeds
| |
70024
|
Source Holder for Mick® Cartridge | |
70026
|
Source holder for 5cc and 10cc MetastronTM Syringes
| |
70032
|
Source Holder for Bard Express Seeding Cartridge |
Rapid Strand, Metastron, and OncoSeed are trademarks of Amersham plc.
LONG TERM STABILITY OF HDR 1000 plus ION CHAMBER
Results of re-calibrations show the long term stability is an excellent 0.16%.
| | | | | | |
SN
|
Initial Calibration
|
Second Calibration
|
Month Interval
|
Change
|
% Change
| | |
Ci/nA |
Ci/nA | | | | |
33
|
0.1250
|
0.1249
|
27
|
-0.0001
|
-0.08%
| |
64
|
0.1250
|
0.1252
|
26
|
0.0002
|
0.16%
| |
63
|
0.1256
|
0.1259
|
24
|
0.0003
|
0.24%
| |
62
|
0.1250
|
0.1253
|
24
|
0.0003
|
0.24%
| |
88
|
0.1253
|
0.1256
|
13
|
0.0003
|
0.24%
| |
44
|
0.1278
|
0.1280
|
15
|
0.0002
|
0.16%
| |
92
|
0.1251
|
0.1252
|
12
|
0.0001
|
0.08%
| |
5
|
0.1266
|
0.1270
|
21
|
0.0004
|
0.32%
| |
82
|
0.1294
|
0.1292
|
21
|
-0.0002
|
-0.15%
| |
81
|
0.1273
|
0.1275
|
25
|
0.0002
|
0.16%
| |
31
|
0.1268
|
0.1270
|
17
|
0.0002
|
0.16%
| |
34
|
0.1267
|
0.1270
|
25
|
0.0003
|
0.24%
| |
12
|
0.1298
|
0.1297
|
25
|
-0.0001
|
-0.08%
| |
14
|
0.1299
|
0.1285
|
25
|
-0.0014
|
-1.08%
| |
O33
|
0.1271
|
0.1271
|
35
|
0.0000
|
0.00%
| |
O2B
|
0.125
|
0.1254
|
36
|
0.0004
|
0.32%
| |
581
|
0.1289
|
0.1289
|
24
|
0.0000
|
0.00%
| |
745
|
0.1279
|
0.1277
|
24
|
-0.0002
|
-0.16%
| |
431
|
0.1279
|
0.1276
|
22
|
-0.0003
|
-0.23%
| |
433
|
0.1272
|
0.1270
|
23
|
-0.0002
|
-0.16%
| |
332
|
0.1268
|
0.1266
|
25
|
-0.0002
|
-0.16%
| |
743
|
0.1279
|
0.1276
|
28
|
-0.0003
|
-0.23%
| |
381
|
0.1286
|
0.1286
|
25
|
0.0000
|
0.00%
| |
451
|
0.1278
|
0.1277
|
26
|
-0.0001
|
-0.08%
| |
453
|
0.1269
|
0.1271
|
24
|
0.0002
|
0.12%
| |
3044
|
0.1281
|
0.1280
|
24
|
-0.0001
|
-0.08%
| |
450
|
0.1273
|
0.1272
|
24
|
-0.0001
|
-0.08%
| |
335
|
0.1268
|
0.1260
|
26
|
0.0000
|
0.00%
| |
3454
|
0.1260
|
0.1262
|
26
|
0.0002
|
0.16%
| |
30263
|
0.1269
|
0.1270
|
25
|
0.0001
|
0.08%
| |
30262
|
0.1268
|
0.1271
|
26
|
0.0003
|
0.24%
| |
32044
|
0.1283
|
0.1282
|
24
|
-0.0001
|
-0.08%
| |
32304
|
0.1265
|
0.1260
|
26
|
-0.0005
|
-0.04%
| |
32041
|
0.1279
|
0.1279
|
26
|
0.0000
|
0.00%
| |
30269
|
0.1269
|
0.1268
|
28
|
-0.0001
|
-0.08%
| |
33093
|
0.1270
|
0.1267
|
26
|
-0.0003
|
-0.24%
| |
31444
|
0.1281
|
0.1280
|
30
|
-0.0001
|
-0.08%
| | | | | | | |
Average change 0.16%
If you are interested in any of the products mentioned here, please fill out an Enquiry Form or a Quotation Request Form, so that we may promptly respond to your request.
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Please contact Colin Walters at cwalters@seedos.com if you would like further information or you have questions
or comments about this web site.
SeeDOS Ltd, 26, The Maltings, Leighton Buzzard, Bedfordshire LU7 4BS, United Kingdom
Tel: +44 1525 850 670 • Fax: +44 1525 850 685
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