Mammographic Accreditation Phantom

Transcription

1 Quality Control in Mammography RMI 156 Mammographic Accreditation Phantom RMI 156 A User s Guide GAMMEX RMI

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3 Table of Contents Product Overview Product Description Using the Phantom References Sales and Service Product Warranty

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5 Product Warranty WARRANTY, DISCLAIMERS AND LIMITATION OF LIABILITY: The Products are covered by the warranty set forth in the following paragraphs. The warranty is extended only to the purchaser of the Products directly from Seller (or an authorized dealer of Seller) as new merchandise. For a period of twelve (12) months from the date of original delivery to Buyer, the Products are warranted to be free from functional defects in materials and workmanship, provided they are operated under condition of normal use, and that repairs and replacements are made in accordance herewith. Seller does not warrant bulbs. The foregoing warranty shall not apply to Products that have been disassembled, altered or repaired (other than proper replacement bulbs) other than by Seller or if the Product has been subject to abuse, misuse, negligence or accident. Seller s sole and exclusive warranty obligation and Buyer s sole and exclusive warranty consists of Seller, at its option, repairing or replacing free of charge Products: (a) which contain a defect covered by the above warranty; (b) which are reported in writing to Seller not later than seven (7) days after the expiration of the twelve month warranty period; (c) which are returned to Seller promptly after discovery of the defect; and (d) which are found to be defective by Seller upon Seller s examination. Buyer shall pay all transportation charges. SELLER SHALL NOT BE OTHERWISE LIABLE FOR ANY DAMAGES, INCLUDING, WITHOUT LIMITATION, LOSS OF PROFITS OR OVERHEAD, REIMBURSEMENT, PER- SONAL INJURY OR PROPERTY DAMAGE. THE AFORESAID WARRANTY OBLIGATION OF SELLER CONSTITUTES ITS SOLE LIABILITY, AND UNDER NO CIRCUMSTANCES, SHALL THE MAXIMUM LIABILITY OF SELLER UNDER ANY LEGAL THEORY (e.g. CONTRACT, WARRANTY, NEGLIGENCE, PROMIS- SORY, ESTOPPEL, STRICT LIABILITY, MISREPRESENTATION, TORT) AND FOR ANY REASON WHATSOEVER (e.g. DEFECT, DELAY OR OTHERWISE) EXCEED THE PURCHASE PRICE OF THE DEFECTIVE PART, REGARDLESS WHETHER THE CLAIM IS ASSERTED BY BUYER OR ANY OTHER PERSON OR ENTITY. THE LIABILITIES OF SELLER, AS ABOVE SET FORTH, SHALL NOT BE EXTENDED BECAUSE OF ADVICE GIVEN BY IT IN CONNECTION WITH THE DESIGN, INSTALLATION OR USE OF THE PRODUCTS OR PARTS THEREFOR. Product Overview The Mammographic Accreditation Phantom RMI 156 is designed to test the performance of a mammographic system by a quantitative evaluation of the system s ability to image small structures similar to those found clinically. Objects within the phantom simulate micro-calcifications, fibrous structures in ducts, and tumor-like masses. The Mammographic Accreditation Phantom can determine if your mammographic system can detect small structures that are important in the early detection of breast cancer. Test objects within the phantom range in size from those that should be visible on any system to objects that will be difficult to see even on the best mammographic systems. THERE ARE NO EXPRESS OR IMPLIED WARRANTIES WHICH EXTEND BEYOND THE WARRANTIES SET FORTH ABOVE. SELLER MAKES NO WAR- RANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE WITH RESPECT TO THE PRODUCTS OR ANY PARTS THEREOF. GAMMEX, Inc., May US10 Rev #2 8 1

6 Product Description The Mammographic Phantom is made up of a wax block containing 16 various sets of test objects, a 3.3 cm (1.3 in.) thick acrylic base, a tray for placement of the wax block, and a 0.3 cm (0.12 in.) thick cover. All of this together approximates a 4.2 cm compressed breast. Five groups of simulated micro-calcifications, six different size nylon fibers simulate fibrous structures, and five different size tumor-like masses are included in the wax insert. Figure 1 lists the sizes of the test objects and their position in relation to the notched corner of the wax block. Sales and Service GAMMEX RMI is committed to satisfying our customers needs. If you have any questions, comments, or suggestions regarding our products and service, please call or fax us. Our Sales and Service Department is open Monday through Friday, 8:00 am to 6:30 pm Central Time. GAMMEX RMI 2500 West Beltline Hwy. at University Avenue P.O. Box Middleton, WI U.S.A. 1-(800) GAMMEX-1 [ ] FAX sales@gammex.com Figure 1: Location of the test objects in the wax insert. Note: Numbers are for reference only. 2 7

7 References 1. L.A. DeWerd Diagnosis of Artifact Sources in the Xeroradiographic System (Quality Assurance), CRP Report Series #2, Medical Physics Division, University of Wisconsin, Madison, WI 53706, L.A. DeWerd, John F. Wochos, and John R. Cameron. Wisconsin Mammographic Phantoms, Department of Radiology, University of Wisconsin, Madison, WI 53706, Wende W. Logan, and E. Phillip Muntz, Reduced Dose Mammography, Masson Publishing Co., New York, L.A. DeWerd. Mammography Quality Assurance, Medical Electronics 19, (1988). 5. R. Edward Hendrick, Ph.D. Requirements for Quality Breast Cancer Detection, ACS Proceedings of the Workshop on Early Breast Cancer Detection. 6. Stewart C. Bushong, Sc.D. Techs Must Take Charge of QC in Mammography, Diagnostic Imaging, April Region Materials mm nylon fiber mm nylon fiber mm nylon fiber mm nylon fiber mm nylon fiber mm nylon fiber mm simulated micro-calcification mm simulated micro-calcification mm simulated micro-calcification mm simulated micro-calcification mm simulated micro-calcification mm thick tumor-like mass mm thick tumor-like mass mm thick tumor-like mass mm thick tumor-like mass mm thick tumor-like mass 7. American College of Radiology. Mammography Quality Control,

8 4 Using the Phantom 1. Place the phantom on the image receptor surface in the same position as a breast. The nipple indent marker should be positioned away from the chest wall, just as the nipple of the patient s breast would be positioned. 2. Position the x-ray tube and compression device as you would for a craniocaudal examination. 3. Choose the kvp and mas factors you would use for a 4.2 cm compressed breast. 4. If the phototimer is used, set the phototimer to the center position under the wax portion of the phantom. Use the phototimer settings as you would for an average 4.2 cm compressed breast. 5. Make an exposure and process the exposed film. This image represents the imaging abilities of your machine using these clinical factors. 6. If the image is over- or under-exposed, make a suitable adjustment in your factors and repeat the exposure. This is an indication that adjustments may be necessary for patient imaging and should be checked. Background optical should be greater than 1.2 OD. 7. Once an acceptable image has been obtained, have one or more viewers identify and record which objects are seen. Use a magnifying glass to look for the structures as you would on a patient s mammogram. A good imaging system should be able to image the 0.32 mm simulated micro-calcification, 0.75 mm nylon fiber, and the 0.75 mm mass. 8. Assign each viewed test object a score of one. If only half of an object or 3 to 4 of the simulated micro-calcifications are seen, half scores may be used. ACR criteria requires a score of 4 for fibrils, 3 for simulated micro-calcifications, and 3 for masses. As an example for the scoring system, assume a mammographic system images fibers 1 through 4, simulated microcalcifications 7 through 9 and masses 12 through 14. The image score for this system would be fibrils 4, simulated micro-calcifications 3, masses 3. If your mammographic unit is significantly worse, you may wish to check the accuracy of the kvp, the focal spot size, the half value layer, and the image processor. You should also consult with a medical physicist or engineer who specializes in mammography and/or diagnostic radiology. Table 1: Suggested Image Scoring System for the Mammographic Accreditation Phantom RMI 156. Refer to Figure 1 for test object numbering. 5