Reducing Radiation Exposure from Survey CT Scans
|
|
- Tracey Cannon
- 6 years ago
- Views:
Transcription
1 Reducing Survey CT Scan Exposure Pediatric Imaging Original Research Jennifer C. O Daniel 1 Donna M. Stevens 2 Dianna D. Cody 2 O Daniel JC, Stevens DM, Cody DD Received July 28, 2004; accepted after revision October 15, Department of Radiation Physics, Unit 94, The University of Texas M. D. Anderson Cancer Center, Houston, TX Department of Imaging Physics, Unit 56, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX Address correspondence to D. D. Cody. AJR 2005; 185: X/05/ American Roentgen Ray Society Reducing Radiation Exposure from Survey CT Scans OBJECTIVE. The purpose of this study was to focus attention on the technique factors commonly used in survey CT scans (e.g., scout, topogram, or pilot scans) to measure the radiation exposure from typical survey CT scans, to compare their exposure to that of typical chest radiographs, and to explore methods for radiation exposure reduction. MATERIALS AND METHODS. The default survey CT scans on 21 CT scanners, representing three different vendors and 11 different models, were investigated. Exposure measurements were obtained with an ion chamber at isocenter and adjusted to be consistent with standard chest radiographic exposure measurement methods (single posterior anterior projection). These entrance exposures were compared with those of typical chest radiographs, for which the mean for average-sized adults is 16 mr ( C/kg). RESULTS. The entrance exposures of the default survey CT scans ranged from 3.2 to 74.7 mr (0.8 to C/kg), which is equivalent to approximately 0.2 to 4.7 chest radiographs. By changing the default scan parameters from 120 kvp to 80 kvp and the tube position from 0 (tube above table) to 180 (tube below table), the entrance exposure for the survey CT scan was reduced to less than that of one chest radiograph for all CT scanners. CONCLUSION. For institutions at which the interpreting radiologists do not rely heavily on the appearance of the survey CT image, we recommend adjusting the technique parameters (kilovoltage and X-ray tube position) to decrease radiation exposure, especially for vulnerable patient populations such as children and young women. he current medical climate requires careful consideration of ra- T diographic techniques for pediatric CT examinations, adapting the CT parameters for the patient s size [1 7]. Furthermore, a single routine CT protocol is not appropriate for all adults or for all imaging tasks. Very large adults often require a substantially higher CT technique to produce clinically acceptable image quality. CT parameters also may need adjustment for specific indications (e.g., renal stone protocols). Recently, the CT community has begun to recognize that small adults would benefit from a more size-appropriate CT technique [8 17]. In addition to the X-ray tube current and scanning time/rotation, CT operators can adjust the X-ray tube voltage, pitch, or some combination of these parameters according to patient size factors and the imaging task. The contribution of the survey CT scan (also referred to as the scout, topogram, or pilot scan) to the total radiation dose of a CT examination typically has been considered negligible. While the dose from the survey CT scan is quite small compared with the dose from the tomographic portion of the examination, the former readily can be measured and compared with typical doses from chest radiographs. The effects of radiation exposure at the level of chest radiographs is not well understood; therefore, we should follow the principle of ALARA (as low as reasonably achievable) and minimize the dose from the survey CT scan whenever possible. This issue generally has been ignored by the imaging physics community. Our study was designed to evaluate the radiation exposure from commonly used survey projection-view CT scans for several CT manufacturers and models and to evaluate how to minimize the radiation exposure by taking advantage of adjustments to X-ray tube kilovoltage, X-ray tube current, and X-ray tube position parameters. Materials and Methods All CT scanners at our institution were available for inclusion in this investigation, resulting in the AJR:185, August
2 Fig. 1 Ion chamber in-air at isocenter for survey CT scan radiation measurement. Inverse-square correction factors were applied to determine entrance exposure for 22.5-cm-diameter patient. Source for 0 projection 0 exposure position Isocenter measurement point 180 exposure position Source for 180 projection evaluation of 21 CT scanners representing three vendors and 11 models. We evaluated models from GE Healthcare, Philips Medical Systems, and Siemens Medical Solutions. Single-slice helical CT scanners and MDCT scanners (4-, 8-, and 16-channel systems) were investigated. Through the manufacturers manuals, discussions with manufacturers representatives, and the default settings of each CT scanner, we collected information on the design and defaults of each CT scanner (e.g., the number of channels, default kvp for survey CT scans, default ma for survey CT scans, default tube positions for survey CT scans, survey CT scan table speed, and survey CT scan beam filtration). We had modified the survey CT scan parameters more than 1 year ago for pediatric patients on the GE Light- Speed scanners to minimize the radiation exposure. The pediatric exposures from the GE LightSpeed scanners are from these user-selected parameters, and not the manufacturer s default parameters. Fig. 2 Typical survey CT scan of ion chamber. Chamber is in center of scanning region. Source-to-isocenter distance Adult = 22.5 cm Child = 14 cm Fig. 3 Diagram of hypothetical 22.5-cm-patient setup. Measurements were obtained at isocenter, and source-to-isocenter distance was known. We used inverse-square correction factors to determine anteroposterior (0 ) and posteroanterior (180 ) entrance exposures for a hypothetical 22.5-cm adult patient and a hypothetical 14-cm pediatric patient, to compare our results to typical adult chest radiograph entrance exposure (16 mr or C/kg). Our goal was to measure the entrance exposure of typical adult and pediatric patients, and determine how much altering any of the scanning parameters (kvp, ma, tube position) would reduce the entrance exposure. Therefore we studied both the default survey CT scan techniques programmed into the current routine clinical protocols and the minimum possible survey CT scan techniques. We chose to concentrate on the survey CT scans associated with body scan techniques (i.e., chest and abdomen scans). Survey CT scans of the head typically used lateral tube positions and higher ma than do survey CT scans of the body. We measured the radiation exposure-in-air from three different survey CT scan techniques on every CT scanner. (The measurement technique will be thoroughly described in the following paragraph.) We measured each technique (kvp and ma combination) at the two tube positions. The first technique we measured was the default X-ray tube voltage and default X-ray tube current at anteroposterior (0, or A/P) and posteroanterior (180, or P/A) X-ray tube positions. If the default child and adult techniques were not identical, then we collected data for both. Second, we examined a technique of 120 kvp and the minimum X-ray tube current at 0 and 180 X-ray tube positions. If the 120 kvp setting was not available, we chose the 130 kvp setting instead. Third, we measured a technique of 80 kvp and the minimum X-ray tube current at 0 and 180 X-ray tube positions. To provide a fair comparison between the 120 kvp and 80 kvp data, the minimum X-ray tube current chosen was the minimum current that could be used at both voltage levels. For example, if the lowest X-ray tube current available with 80 kvp was 40 ma but the minimum available with 120 kvp was 10 ma, 40 ma was used for both measurements. For all techniques we used the parameters associated with a survey CT scan of the body. We believe that our 510 AJR:185, August 2005
3 Reducing Survey CT Scan Exposure Fig. 4 Set-up for measurement of beam width. Kodak X-Omat V or X- Omat TL ready-pack film (Eastman Kodak Company) is suspended on foam block at isocenter. Table, positioned below and away from film, can move without interfering with film position. results should also apply to survey CT scans of the head, because we found no difference in beam filtration between head and body survey CT scans. Survey CT scans, which are 2D radiographic images, are more comparable to chest projection radiographs than to tomographic CT scans. Therefore, we chose to measure the radiation exposure from the survey CT scans the same way exposure is measured for a chest projection radiography system [18]. A RadCal model 9010 (Radcal Corp.) electrometer and a 6 cc cylindric ion chamber (Radcal model ) were used for this study. The ion chamber was placed on top of a Styrofoam block on the CT table and positioned so that the center of the chamber volume would pass through the isocenter of the gantry during the acquisition of a projection radiograph (Fig. 1). A projection view was acquired such that the chamber and its stem were in the approximate center of the image (Fig. 2). The same portion of chamber stem was irradiated during each measurement. Exposure in air values (mr) was recorded and averaged for two or more measurements obtained with each technique and X-ray tube position. To compare the measurements taken at the CT gantry isocenter to the entrance exposure measurements for a chest radiograph, inverse-square corrections were applied to the collected exposure readings. Standard adult chest radiographic exposure measurements are obtained by placing the ion chamber 22.5 cm in front of the imaging detector [18]. For our measurements, the source-to-isocenter distance was known for each CT scanner and the patient was assumed to be centered at isocenter. Assuming a thickness of 22.5 cm (A/P) for the adult chest, the readings were corrected to the anterior surface for 0 tube positions and to the posterior surface for 180 tube positions (Fig. 3). We selected 14 cm to represent the chest wall thickness of a child, based on the thickness of our 5-year-old pediatric anthropomorphic phantom (ATOM Dosimetric Phantoms, Computer Imaging Reference Systems). The pediatric exposure estimations were corrected to the anterior and posterior surfaces of a 14-cm-thick pediatric chest. In the most recent Nationwide Evaluation of X-ray Trends (NEXT) study, radiation exposure to an average-sized adult from a typical chest radiograph ranged from less than 5 mr ( C/kg) to above 31 mr ( C/kg), with a mean value of 16 mr ( C/kg) [18]. This is slightly lower than the mean exposure reported in the previous NEXT study in 1984 of 20 mr ( C/kg) [19]. For our study, we assumed a midrange value of 16 mr ( C/kg) per adult chest radiograph. Factors other than X-ray tube voltage, X-ray tube current, and X-ray tube position can affect the survey CT scan radiation exposure. We also investigated the survey CT scan beam width, the survey CT scan beam filtration, and the survey CT scan table speed for each CT platform. We chose to operate the CT scanners in clinical mode rather than service mode to be certain our measurements corresponded to typical clinical CT scanner usage. In clinical mode the table moves during the scout scan, so the physical beam width cannot be measured by placing film on the table. Instead, the physical beam width at isocenter in survey CT scan mode for each scanner model was measured using a foam block suspended in the bore of the CT scanner. A piece of Kodak X-Omat V or X-Omat TL ready-pack film (Eastman Kodak Company) was placed on it horizontally at the isocenter (Fig. 4). A survey CT scan was then taken with the table positioned away from the film, and the beam width was measured using a 7 magnifier with graticule (a network of lines, each marking 0.1-mm spacing, in the focal plane of the eyepiece of the optical magnifier). The table speed and beam filtration were de- termined by examination of the CT scanner model specifications and by discussions with manufacturer s representatives when necessary. This information was used to select exposure time(s) for appropriate optical density for the beam width measurements. Results The projection scan default values are displayed in Table 1. For 8 of 11 models, the default X-ray tube position was set at the 0 position for adult survey CT scans, that is to say, typically A/P projections and not P/A projections were part of routine adult CT protocols for supine patients. For 6 of 11 models, the projection scan default values were the same for adult and pediatric patients. With these settings, the radiation exposure ranged from 3.9 mr to 74.7 mr ( C/kg to C/kg) for an average adult and 3.2 mr to 47.6 mr ( C/kg to C/kg) for an average pediatric patient (Fig. 5). Therefore, we estimated that the radiation exposure from a default survey CT scan was equivalent to that from 0.2 to 4.7 adult chest radiographs, assuming 16 mr ( C/kg) per chest radiograph. The projection view technique (combination of X-ray tube voltage, current, and position) was found, as expected, to be consistent for scanners of the same make and model. Survey CT scan beam widths ranged from 2 mm to 7.5 mm (Table 2). Table speeds were 75 mm/sec or 100 mm/sec. The GE and Siemens models used a beam-shaping filter typically used for body tomographic scans during the survey CT scans. The three Philips platforms used only inherent filtration (no additional filters) for their survey CT scans. We expected that wider beam widths and slower table speeds would increase the measured radiation exposure. However, we did not observe a clear relationship between beam width, table speed, and radiation exposure. The measured entrance exposure values observed when varying X-ray tube voltage and current parameters for each scanner included in the investigation are shown in Table 3 and Figure 6. For two models, only 130 kvp was available for survey CT scans. For a third model, only a 120 kvp and 50 ma combination could be used for survey CT scans. By using a 180 tube position, projection view exposure was reduced by a mean of 20% relative to the standard 0 technique. By using this method, the exposure was reduced by a mean of 6.2 mr ( C/kg, range = 3.4 mr to 13.0 mr [0.9 to C/kg]) at 120 kvp AJR:185, August
4 and by a mean of 2.2 mr ( C/kg, range = 1.6 mr to 3.1 mr [0.4 to C/kg]) at 80 kvp. When the X-ray tube voltage was reduced to the minimum possible value (from 120 kvp to 80 kvp for most scanners), the exposure for both the 0 and the 180 techniques was reduced by a mean of 64% (reduced by approximately 1.1 chest radiographs). When both the minimum X-ray tube voltage and the 180 geometry were used, the exposure due to the projection view was reduced by a mean total of 71% (or 20.7 mr [ C/kg], reduced by approximately 1.3 chest radiographs) among all scanners and models. Switching from a 120 kvp, 0 technique to an 80 kvp, 180 technique resulted in entrance exposure levels of 5.8 mr ( C/kg) to 12.2 mr ( C/kg), or 0.4 to 0.8 chest radiographs. Discussion We found that the default survey CT scan protocols were fairly uniform for each vendor. The Philips scanners used a default 180 tube position but had high X-ray tube voltage and/or current values. All GE Healthcare scanners used a default 0 tube position and 120 kvp. The single-slice GE helical scanners (HiSpeed) had a large range of user-selectable X-ray tube currents from 10 ma to 80 ma. The multislice helical GE LightSpeed scanners had the same default parameters for adult patients, using 120 kvp, 10 ma, and 0 tube positions. The pediatric default parameters on the GE LightSpeed scanners had been user-selected during the previous year. We had only one Siemens model (two scanners) available; it also had a 0 projection as its default setting. The Siemens Somatom Sensation 16 provided different default scanning protocols for adults and children. The definition of child and pediatric varies from institution to institution. At our TABLE 1: Default Survey CT Scan Settings and Exposure Values for 11 CT Models Number of Measured Exposure (mr) Scanner Model Scanners kvp ma Tube Position Adult Child GE HiSpeed ZX/i GE HiSpeed CT/i GE HiSpeed FX/i a GE LightSpeed QX/i (adult), 80 (child) b 10 0 (adult), 180 (child) b GE LightSpeed Plus (adult), 80 (child) b 10 0 (adult), 180 (child) b GE LightSpeed Ultra (adult), 80 (child) b 10 0 (adult), 180 (child) b GE Lightspeed (adult), 80 (child) b 10 0 (adult), 180 (child) b Philips PQ Philips Ultra Z Philips Mx8000 IDT Siemens Somatom Sensation (adult), 80 (child) 100 (adult), 50 (child) Note All values reflect the adult body routine protocols except where otherwise noted. a EXaCT Targeting System. b These settings are not the manufacturers defaults for the survey CT scan, but rather had been previously selected by the user to minimize the radiation exposure to pediatric patients. Entrance Exposure (mr) GE HiSpeed ZX/i Default Child Default Adult GE HiSpeed CT/i GE HiSpeed Fx/i GE LightSpeed QX/i GE LightSpeed Plus GE LightSpeed 16 GE LightSpeed Ultra Philips PQ5000 Philips Ultra Z Philips Mx8000 IDT 16 Siemens Somatom Sensation 16 Fig. 5 Survey CT scan mean entrance exposures with default scanner settings. Horizontal dotted line marks exposure from one typical chest X-ray (16 mr or C/kg). Asterisk symbols denote pediatric survey CT scans that were not truly default but had been adjusted to minimum settings 1 year before the initiation of this study. 512 AJR:185, August 2005
5 Reducing Survey CT Scan Exposure TABLE 2: Model, Beam Width, and Table Speed of 11 CT Models Scanner Model First Available Number of Channels Beam Width (mm) Table Speed (mm/sec) Beam Filtration GE HiSpeed ZX/i Std body filter GE HiSpeed CT/i Std body filter GE HiSpeed FX/i a Std body filter GE LightSpeed QX/i Std body filter GE LightSpeed Plus Std body filter GE LightSpeed Ultra Std body filter GE LightSpeed Std body filter Philips PQ5000 ~ None Philips Ultra Z ~ None Philips Mx8000 IDT 16 ~ None Siemens Somatom Sensation Std body filter Note Std=standard. EXaCT Targeting System. TABLE 3: Measured Entrance Exposures on 21 CT Scanners at Minimum ma for a Typical Adult (Assuming 22.5-cm Anteroposterior Chest Thickness) Scanner ma 130 kvp, kvp, kvp, kvp, kvp, 0 80 kvp, 180 GE HiSpeed ZX/i 40 N/A N/A GE HiSpeed CT/i (1) 40 N/A N/A GE HiSpeed CT/i (2) 40 N/A N/A GE HiSpeed FX/i 60 N/A N/A GE LightSpeed QX/i (1) 10 N/A N/A GE LightSpeed QX/i (2) 10 N/A N/A GE LightSpeed QX/i (3) 10 N/A N/A GE LightSpeed QX/i (4) 10 N/A N/A GE LightSpeed Plus (1) 10 N/A N/A GE LightSpeed Plus (2) 10 N/A N/A GE LightSpeed Plus (3) 10 N/A N/A GE LightSpeed Plus (4) 10 N/A N/A GE LightSpeed Ultra (1) 10 N/A N/A GE LightSpeed Ultra (2) 10 N/A N/A GE LightSpeed 16 (1) 10 N/A N/A GE LightSpeed 16 (2) 10 N/A N/A Philips PQ a a a a Philips Ultra Z a a a a Philips Mx8000 IDT N/A N/A a 59.6 a a Siemens Somatom Sensation 16 (1) 50 N/A N/A Siemens Somatom Sensation 16 (2) 50 N/A N/A Note N/A = not applicable. Because 120 kvp was available, no 130 kvp measurements were taken. a Survey CT scans were not available at these parameters. clinic, pediatric patients are patients ages 15 years or younger, unless they are obviously almost fully developed at a younger age. In this article, pediatric patients are those patients 15 years or younger whose display field-of-view (DFOV) was 35 cm or less. We predicted that increasing the beam width and decreasing the table speed would increase the radiation exposure from survey CT scans. However, we did not observe that variations in beam width or table speed had a clear effect on exposure, likely owing to the Mean Entrance Exposure (mr) many complicating factors (X-ray tube voltage, current, and position). Beam filtration also had no discernable effect between scanners, probably because a similar filter was used for all scanners. The GE LightSpeed series had a greater table speed and beam width AJR:185, August
6 12 Entrance Exposure (mr) GE HiSpeed ZX/i 130 kvp, A/P 120 kvp, A/P 80 kvp, A/P 40 ma 40 ma GE HiSpeed CT/i 60 ma 130 kvp, P/A 120 kvp, P/A 80 kvp, P/A GE HiSpeed Fx/i GE LightSpeed QX/i GE LightSpeed Plus GE LightSpeed Ultra Fig. 6 Mean entrance exposure for survey CT scans at minimum X-ray tube current indicated for each scanner model. Horizontal dotted line marks exposure from one typical chest X-ray (16 mr or C/kg). Whenever available, 120 kvp and 80 kvp X-ray tube voltages were used. For two CT scanner models (Philips PQ5000 and Philips Ultra Z), only 130 kvp X-ray tube voltage was available for survey CT scans. For one CT scanner model (Philips Mx8000 IDT 16), only 120 kvp and a 0 tube position were available. 10 ma 10 ma 10 ma 10 ma GE LightSpeed ma Philips PQ ma 50 ma 50 ma Philips Ultra Z Philips Mx8000 IDT 16 Siemens Somatom Sensation 16 than the GE HiSpeed FX/i series but the same default survey CT settings; however, the GE HiSpeed FX/i scanner had much lower radiation exposure measurements than the GE LightSpeed scanners. The faster table speed of the GE LightSpeed (100 mm/sec vs 75 mm/sec) might not fully compensate for its wider beam width (7.5 mm vs 2 mm). The radiation exposure associated with the survey CT scans generally has been considered negligible in the CT physics literature or has been ignored altogether. While this exposure is small compared with that from the tomographic data acquisitions, the radiation exposures from the default survey CT scans in our investigation typically were equivalent to chest radiographs (Fig. 5). Within the same make and model, radiation exposure values were always within ± 2.1 mr ( C/kg) of the mean radiation exposure. There was a wide range of radiation exposures between the different CT platforms at their default settings, with the child default radiation exposure ranging from 3.2 to 47.6 mr (0.8 to C/kg) and the adult default radiation exposure ranging from 3.9 to 74.7 mr (1.0 to C/kg). It is important for all institutions to check the default settings for survey images on each CT platform to make certain they are using as low a technique as possible for their applications. Figure 6 compares the various CT platforms for the same kvp and tube position settings. The ma displayed is the minimum ma allowed at that kvp for that particular CT platform. Even though there is a range of radiation exposures between the different CT platforms, those exposures can be reduced substantially by dropping the kvp and/or rotating the tube to 180. The lowest exposures were achieved using 80 kvp, minimum X-ray tube current, and a 180 tube position. If these settings can be used for survey CT scans, the associated radiation exposure could be reduced to that of less than one chest radiograph. We recommend that the 180 tube position be implemented in place of the 0 tube position for all survey CT scans. This change should not affect image quality, since the radiation passes through both the table and the patient for 0 and 180 tube positions. However, the patient s radiation exposure would be reduced if the radiation beam strikes the table first, allowing it to absorb the lowest-energy X-rays. By the same logic, the radiation exposure of the breast in particular will be decreased. When the X-ray tube voltage or current is altered the image quality will be affected. We suggest that sites determine the minimum acceptable image quality for their survey CT images. They then can determine the appropriate combination of X-ray tube voltage and current needed to achieve that level of image quality while minimizing the radiation exposure of the patient. If the survey CT scan is routinely interpreted as a projection radiograph as part of the overall CT examination, it will be very important to maintain acceptable image quality. In addition, if the survey CT image is used to provide patient geometric information for a variable ma program, the quality of the survey CT scan may need to be maintained in order for the tomographic image quality to remain reliable. However, if the survey CT scan is used only to determine the limits of the tomographic examination by locating bony or other high-contrast landmarks, high-quality survey CT images may not be needed. In these cases we suggest that sites consider decreasing their X-ray tube voltage and current so that the relative radiation exposure from the survey CT scan is as low as possible while maintaining adequate visualization of anatomic landmarks used when establishing scan limits. We recommend that CT clinics in which pediatric examinations are performed reduce their X-ray tube voltage and current to the minimum possible values (80 kvp and ma for our scanners). In addition, if both P/A (180 ) and lateral survey CT scans are not necessary for defining a tomographic acquisition, then only one survey CT scan should be acquired. Both A/P and lateral survey CT scan views are commonly included as a default setting in some scan protocols even though both views are not routinely used. Size-specific determination of X-ray tube voltage and current also should be considered, particularly for pediatric cases. We implemented these changes (80 kvp, 10 ma, 180 tube position) in our pediatric CT protocols at this institution on our GE LightSpeed platform scanners approximately 1 year ago and have had no complaints from the radiologists or technologists concerning the quality of the survey CT images. Small adults also could benefit from these changes. In summary, we have established a method for evaluating the radiation exposure from survey CT scans by measuring the exposure at isocenter and then correcting to an entrance exposure position for comparison to chest radiograph exposures. We measured the entrance exposures associated with survey CT scans using the default pa- 514 AJR:185, August 2005
7 Reducing Survey CT Scan Exposure rameters for 21 CT scanners (11 CT models) at our institution and found that the exposure levels were equivalent to chest radiographs. By changing the acquisition parameters of the survey CT scan, we reduced the exposure to less than one chest radiograph. Implementing these changes, particularly in children and young women, will help ensure that our patients receive as low as reasonably achievable doses from their CT examinations. Acknowledgments We thank John Zullo and Richard Wu for their assistance with the Philips scanners. References 1. Brenner D, Elliston C, Hall E, et al. Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR 2001; 176: Donnelly LF, Emery KH, Brody AS, et al. Minimizing radiation dose for pediatric body applications of single-detector helical CT: strategies at a large children s hospital. AJR 2001; 176: Paterson A, Frush DP, Donnelly LF. Helical CT of the body: are settings adjusted for pediatric patients? AJR 2001; 176: Brenner DJ. Estimating cancer risks from pediatric CT: going from the qualitative to the quantitative. Pediatr Radiol 2002; 32: ; discussion Frush DP. Pediatric CT: practical approach to diminish the radiation dose. Pediatr Radiol 2002; 32: ; discussion Cody DD, Moxley DM, Krugh KT, et al. Strategies for formulating appropriate MDCT techniques when imaging the chest, abdomen, and pelvis in pediatric patients. AJR 2004; 182: Donnelly LF, Frush DP. Pediatric multidetector body CT. Radiol Clin North Am 2003; 41: Cohnen M, Fischer H, Hamacher J, et al. CT of the head by use of reduced current and kilovoltage: relationship between image quality and dose reduction. Am J Neuroradiol 2000; 21: Rehani MM, Berry M. Radiation doses in computed tomography: the increasing doses of radiation need to be controlled. BMJ 2000; 320: Haaga JR. Radiation dose management: weighing risk versus benefit. AJR 2001; 177: Kalra MK, Prasad S, Saini S, et al. Clinical comparison of standard-dose and 50% reduced-dose abdominal CT: effect on image quality. AJR 2002; 179: Frush DP. Responsible use of CT. Radiology 2003; 229: Katz DS, Venkataramanan N, Napel S, et al. Can low-dose unenhanced multidetector CT be used for routine evaluation of suspected renal colic? AJR 2003; 180: Rogers LF. Low-dose CT: how are we doing? AJR 2003; 180: Tack D, De Maertelaer V, Gevenois PA. Dose reduction in multidetector CT using attenuation-based online tube current modulation. AJR 2003; 181: Kalra MK, Maher MM, Toth TL, et al. Strategies for CT radiation dose optimization. Radiology 2004; 230: Maher MM, Kalra MK, Toth TL, et al. Application of rational practice and technical advances for optimizing radiation dose for chest CT. J Thorac Imaging 2004; 19: Kaczmarek RV, Conway BJ, Slayton RO, et al. Results of a nationwide survey of chest radiography: comparison with results of a previous study. Radiology 2000; 215: Butler PF, Conway BJ, Suleiman OH, Koustenis GH, Showalter CK. Chest radiography: a survey of techniques and exposure levels currently used. Radiology 1985; 156: AJR:185, August
A comparison of two methods for the determination of freein-air geometric efficiency in MDCT
A comparison of two methods for the determination of freein-air geometric efficiency in MDCT Theocharis Berris *1, Kostas Perisinakis 1,, Antonios E. Papadakis and John Damilakis 1, 1 Department of Medical
More informationAutomated dose control in multi-slice CT. Nicholas Keat Formerly ImPACT, St George's Hospital, London
Automated dose control in multi-slice CT Nicholas Keat Formerly ImPACT, St George's Hospital, London Introduction to presentation CT contributes ~50+ % of all medical radiation dose Ideally all patients
More informationDose Reduction and Image Preservation After the Introduction of a 0.1 mm Cu Filter into the LODOX Statscan unit above 110 kvp
Dose Reduction and Image Preservation After the Introduction of a into the LODOX Statscan unit above 110 kvp Abstract: CJ Trauernicht 1, C Rall 1, T Perks 2, G Maree 1, E Hering 1, S Steiner 3 1) Division
More informationTOPICS: CT Protocol Optimization over the Range of Patient Age & Size and for Different CT Scanner Types: Recommendations & Misconceptions
CT Protocol Optimization over the Range of Patient Age & Size and for Different CT Scanner Types: Recommendations & Misconceptions TOPICS: Computed Tomography Quick Overview CT Dosimetry Effects of CT
More information1. Patient size AEC. Large Patient High ma. Small Patient Low ma
Comparison of the function and performance of CT AEC systems CTUG meeting by Emily Field Trainee clinical scientist 14 th th Breakdown CT Automatic Exposure Control (AEC) Background Project Description
More informationSlide 1. Slide 2. Slide 3 ACR CT Accreditation. Multi-Slice CT Artifacts and Quality Control. What are the rules or recommendations for CT QC?
Slide 1 Multi-Slice CT Artifacts and Quality Control Dianna Cody, Ph.D. Chief, Radiologic Physics UT MD Anderson Cancer Center Houston, TX Slide 2 What are the rules or recommendations for CT QC? AAPM
More informationHISTORY. CT Physics with an Emphasis on Application in Thoracic and Cardiac Imaging SUNDAY. Shawn D. Teague, MD
CT Physics with an Emphasis on Application in Thoracic and Cardiac Imaging Shawn D. Teague, MD DISCLOSURES 3DR- advisory committee CT PHYSICS WITH AN EMPHASIS ON APPLICATION IN THORACIC AND CARDIAC IMAGING
More informationInvestigation of the line-pair pattern method for evaluating mammographic focal spot performance
Investigation of the line-pair pattern method for evaluating mammographic focal spot performance Mitchell M. Goodsitt, a) Heang-Ping Chan, and Bob Liu Department of Radiology, University of Michigan, Ann
More informationTest Equipment for Radiology and CT Quality Control Contents
Test Equipment for Radiology and CT Quality Control Contents Quality Control Testing...2 Photometers for Digital Clinical Display QC...3 Primary Workstations...3 Secondary Workstations...3 Testing of workstations...3
More informationQuantitation of clinical feedback on image quality differences between two CT scanner models
Received: 4 August 2016 Revised: 4 November 2016 Accepted: 12 December 2016 DOI: 10.1002/acm2.12050 MEDICAL IMAGING Quantitation of clinical feedback on image quality differences between two CT scanner
More informationI. Introduction.
JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 15, NUMBER 1, 2014 Accuracy of measuring half- and quarter-value layers and appropriate aperture width of a convenient method using a lead-covered case
More informationElectronic Noise in CT Detectors: Impact on Image Noise and Artifacts
Medical Physics and Informatics Original Research Duan et al. Electronic Noise in CT Detectors Medical Physics and Informatics Original Research Xinhui Duan 1 Jia Wang 1,2 Shuai Leng 1 ernhard Schmidt
More informationExposure Indices and Target Values in Radiography: What Are They and How Can You Use Them?
Exposure Indices and Target Values in Radiography: What Are They and How Can You Use Them? Definition and Validation of Exposure Indices Ingrid Reiser, PhD DABR Department of Radiology University of Chicago
More informationX-RAYS - NO UNAUTHORISED ENTRY
Licencing of premises Premises Refer Guidelines A radiation warning sign and warning notice, X-RAYS - NO UNAUTHORISED ENTRY must be displayed at all entrances leading to the rooms where x-ray units are
More informationof sufficient quality and quantity
of sufficient quality and quantity The patient s body attenuates the beam as it passes though the body More energy is deposited in organs located near the entry of the beam than near the exit of the beam
More informationFocal Spot Blooming in CT: We Didn t Know We Had a Problem Until We Had a Solution
Focal Spot Blooming in CT: We Didn t Know We Had a Problem Until We Had a Solution Cynthia H. McCollough, PhD, DABR, FAAPM, FACR Director, CT Clinical Innovation Center Professor of Medical Physics and
More informationTeaching Digital Radiography and Fluoroscopic Radiation Protection
Teaching Digital Radiography and Fluoroscopic Radiation Protection WCEC 20 th Student Educator Radiographer Conference Dennis Bowman, RT(R), CRT (R)(F) Community Hospital of the Monterey Peninsula (CHOMP)
More informationQC Testing for Computed Tomography (CT) Scanner
QC Testing for Computed Tomography (CT) Scanner QA - Quality Assurance All planned and systematic actions needed to provide confidence on a structure, system or component. all-encompassing program, including
More informationDigital radiography (DR) post processing techniques for pediatric radiology
Digital radiography (DR) post processing techniques for pediatric radiology St Jude Children s Research Hospital Samuel Brady, MS PhD DABR samuel.brady@stjude.org Purpose Review common issues and solutions
More informationDose Reduction in Helical CT: Dynamically Adjustable z-axis X-Ray Beam Collimation
Medical Physics and Informatics Original Research Christner et al. CT Dose Reduction Medical Physics and Informatics Original Research Downloaded from www.ajronline.org by 8.243.133.8 on 2/26/18 from IP
More informationExposure in Dental Radiology: A Comparison Between Intra-oral, Panoramic and Tomographic Examinations
Exposure in Dental Radiology: A Comparison Between Intra-oral, Panoramic and Tomographic Examinations S. Baechler 1, P. Monnin 1, A. Aroua 1, J.F. Valley 1, M. Perrier, P. Trueb 3, F.R. Verdun 1 1 University
More informationPitfalls and Remedies of MDCT Scanners as Quantitative Instruments
intensity m(e) m (/cm) 000 00 0 0. 0 50 0 50 Pitfalls and Remedies of MDCT Scanners as Jiang Hsieh, PhD GE Healthcare Technology University of Wisconsin-Madison Root-Causes of CT Number Inaccuracies Nature
More informationTISSUE EQUIVALENT PHANTOMS FOR EVALUATING IN-PLANE TUBE CURRENT MODULATED CT DOSE AND IMAGE QUALITY
TISSUE EQUIVALENT PHANTOMS FOR EVALUATING IN-PLANE TUBE CURRENT MODULATED CT DOSE AND IMAGE QUALITY By RYAN F. FISHER A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
More informationDigital Imaging started in the 1972 with Digital subtraction angiography Clinical digital imaging was employed from the 1980 ~ 37 years ago Amount of
Digital Imaging started in the 1972 with Digital subtraction angiography Clinical digital imaging was employed from the 1980 ~ 37 years ago Amount of radiation to the population due to Medical Imaging
More informationI. PERFORMANCE OF X-RAY PRODUCTION COMPONENTS FLUOROSCOPIC ACCEPTANCE TESTING: TEST PROCEDURES & PERFORMANCE CRITERIA
FLUOROSCOPIC ACCEPTANCE TESTING: TEST PROCEDURES & PERFORMANCE CRITERIA EDWARD L. NICKOLOFF DEPARTMENT OF RADIOLOGY COLUMBIA UNIVERSITY NEW YORK, NY ACCEPTANCE TESTING GOALS PRIOR TO 1st CLINICAL USAGE
More informationImage Quality and Dose. Image Quality and Dose. Image Quality and Dose Issues in MSCT. Scanner parameters affecting IQ and Dose
Image Quality and Dose Issues in MSCT Image Quality and Dose Image quality Image noise Spatial resolution Contrast Artefacts Speckle and sharpness S. Edyvean St. George s Hospital London SW17 0QT Radiation
More informationThe disclaimer on page 1 is an integral part of this document. Copyright November 30, 2017 by AAPM. All rights reserved.
DISCLAIMER: TO THE EXTENT ALLOWED BY LOCAL LAW, THIS INFORMATION IS PROVIDED TO YOU BY THE AMERICAN ASSOCIATION OF PHYSICISTS IN MEDICINE, A NON-PROFIT ORGANIZATION ORGANIZED TO PROMOTE THE APPLICATION
More informationQC by the MPE in Belgium
Acceptance testing of state-of-the-art CT scanners using a new national protocol: first experience on a large number of scanners of different make and model the working group Radiology of the Belgian Hospital
More informationRadiation Dose Modulation. the Multidetector CT Era: From Basics to Practice 1
Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at www.rsna.org/rsnarights. EDUCATION EXHIBIT
More informationRAD 150 RADIOLOGIC EXPOSURE TECHNIQUE II
RAD 150 RADIOLOGIC EXPOSURE TECHNIQUE II APPROVED 12/O2/2011 EFFECTIVE SPRING 2013-14 Prefix & Number RAD 150 Course Title: Radiologic Exposure Technique II & Lab Purpose of this submission: New Change/Updated
More information160-slice CT SCANNER / New Standard for the Future
TECHNOLOGY HISTORY For over 130 years, Toshiba has been a world leader in developing technology to improve the quality of life. Our 50,000 global patents demonstrate a long, rich history of leading innovation.
More informationResearch Support. Dual-Source CT: What is it and How Do I Test it? Cynthia H. McCollough, Ph.D.
Dual-Source CT: What is it and How Do I Test it? Cynthia H. McCollough, Ph.D. CT Clinical Innovation Center Department of Radiology Mayo Clinic College of Medicine Rochester, MN Research Support National
More informationAuthors: Cabral, Ricardo 1 ; Carvoeiras, Pedro 2 ; Fatana, João 2, ; Alves, Rita 1. 1 Centro Hospitalar Lisboa Norte - Hospital de Santa Maria; 2
Authors: Cabral, Ricardo 1 ; Carvoeiras, Pedro 2 ; Fatana, João 2, ; Alves, Rita 1. 1 Centro Hospitalar Lisboa Norte - Hospital de Santa Maria; 2 Medical Consult, SA; Establish a method to correlate image
More informationMultiple Choice Identify the letter of the choice that best completes the statement or answers the question.
RA110 test 3 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. An object 35 cm in width is radiographed at 100 cm SID and at a 50 cm SOD. What
More informationMeasurement of table feed speed in modern CT
JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 15, NUMBER 3, 2014 Measurement of table feed speed in modern CT Atsushi Fukuda, 1,2a Pei-Jan P. Lin, 3 Kosuke Matsubara, 2 Tosiaki Miyati 2 Department
More informationBreast Tomosynthesis. Bob Liu, Ph.D. Department of Radiology Massachusetts General Hospital And Harvard Medical School
Breast Tomosynthesis Bob Liu, Ph.D. Department of Radiology Massachusetts General Hospital And Harvard Medical School Outline Physics aspects of breast tomosynthesis Quality control of breast tomosynthesis
More informationDetector technology in simultaneous spectral imaging
Computed tomography Detector technology in simultaneous spectral imaging Philips IQon Spectral CT Z. Romman, I. Uman, Y. Yagil, D. Finzi, N. Wainer, D. Milstein; Philips Healthcare While CT has become
More informationNATIONWIDE EVALUATION OF X-RAY TRENDS (NEXT) TABULATION AND GRAPHICAL SUMMARY OF 2001 SURVEY OF ADULT CHEST RADIOGRAPHY
CRCPD Publication E-05-2 Available Online at No Charge $15.00 for a Computer-Generated Copy NATIONWIDE EVALUATION OF X-RAY TRENDS (NEXT) TABULATION AND GRAPHICAL SUMMARY OF 2001 SURVEY OF ADULT CHEST RADIOGRAPHY
More informationComputed Tomography. The Fundamentals of... THE FUNDAMENTALS OF... Jason H. Launders, MSc. Current Technology
The Fundamentals of... Computed Tomography Computed Tomography (CT) systems use x-rays to produce images of slices through a patient s anatomy. Despite having lower spatial resolution than other x-ray
More informationdiagnostic examination
RADIOLOGICAL PHYSICS 2011 Raphex diagnostic examination Adel A. Mustafa, Ph.D., Editor PUBLISHED FOR: RAMPS (Radiological and Medical Physics Society of New York) preface The RAPHEX Diagnostic exam 2011
More information2217 US Highway 70 East Garner, NC Main: Fax:
Viztek is committed to providing the highest image quality possible in our CR & DR product lines. There are several factors that directly affect the overall quality of CR & DR based images. The eposure
More informationMammography: Physics of Imaging
Mammography: Physics of Imaging Robert G. Gould, Sc.D. Professor and Vice Chair Department of Radiology and Biomedical Imaging University of California San Francisco, California Mammographic Imaging: Uniqueness
More informationThe effect of compensating filter on image quality in lateral projection of thoraco lumbar radiography
Journal of Physics: Conference Series OPEN ACCESS The effect of compensating filter on image quality in lateral projection of thoraco lumbar radiography To cite this article: N A A Daud et al 2014 J. Phys.:
More informationWide beam CT dosimetry. Elly Castellano
Wide beam CT dosimetry Elly Castellano Outline revision: CT dose indices wide-beam CT: the end of the road for CTDI? the IEC rescue plan for CTDI 100 the american way AAPM report 111 better estimates of
More informationFeatures and Weaknesses of Phantoms for CR/DR System Testing
Physics testing of image detectors Parameters to test Features and Weaknesses of Phantoms for CR/DR System Testing Spatial resolution Contrast resolution Uniformity/geometric distortion Dose response/signal
More informationMammography is a radiographic procedure specially designed for detecting breast pathology Approximately 1 woman in 8 will develop breast cancer over
Mammography is a radiographic procedure specially designed for detecting breast pathology Approximately 1 woman in 8 will develop breast cancer over a lifetime Breast cancer screening programs rely on
More informationDiagnostic X-Ray Shielding
Diagnostic X-Ray Shielding Multi-Slice CT Scanners Using NCRP 147 Methodology Melissa C. Martin, M.S., FAAPM, FACR Therapy Physics Inc., Bellflower, CA AAPM Annual Meeting, Orlando, FL FL Refresher Course
More informationPET/CT Instrumentation Basics
/ Instrumentation Basics 1. Motivations for / imaging 2. What is a / Scanner 3. Typical Protocols 4. Attenuation Correction 5. Problems and Challenges with / 6. Examples Motivations for / Imaging Desire
More informationCHAPTER 2 COMMISSIONING OF KILO-VOLTAGE CONE BEAM COMPUTED TOMOGRAPHY FOR IMAGE-GUIDED RADIOTHERAPY
14 CHAPTER 2 COMMISSIONING OF KILO-VOLTAGE CONE BEAM COMPUTED TOMOGRAPHY FOR IMAGE-GUIDED RADIOTHERAPY 2.1 INTRODUCTION kv-cbct integrated with linear accelerators as a tool for IGRT, was developed to
More informationOverview of Safety Code 35
Common Quality Control Procedures for All s Quality Control Procedures Film All s Daily Quality Control Tests Equipment Warm-up (D1) According to manufacturers instructions Can include auto calibration(d1)
More informationTORNIER BLUEPRINT. 3D Planning + PSI SCAN PROTOCOL
TORNIER BLUEPRINT 3D Planning + PSI SCAN PROTOCOL Contents 3 Introduction 3 Patient preparation 3 Scanning instructions 4 Image instructions 5 Scanning parameters 6 Technical instructions 2 BLUEPRINT 3D
More informationQuality assurance: a comparison study of radiographic exposure for neonatal chest radiographs at 4 academic hospitals
DOI 10.1007/s00247-011-2290-1 ORIGINAL ARTICLE Quality assurance: a comparison study of radiographic exposure for neonatal chest radiographs at 4 academic hospitals Mervyn D. Cohen & Richard Markowitz
More information3D Diode Array Commissioning: Building Confidence in 3D QA Technology
3D Diode Array Commissioning: Building Confidence in 3D QA Technology Caroline Yount, MS CANCER CENTER 3D QA The complex three-dimensional (3D) shapes of intensity modulated radiation therapy (IMRT) dose
More informationWide-Detector CT for TAVR Planning:
Wide-Detector CT for TAVR Planning: Impact on Iodine Dose, Radiation Dose, and Image Quality SCBTMR 2015 Annual Course Thursday, October 8 William P. Shuman MD FSCBTMR Department of Radiology University
More informationCT Basics: Equipment and Instrumentation Module 2
Module 2 Transcript For educational and institutional use. This transcript is licensed for noncommercial, educational in-house or online educational course use only in educational and corporate institutions.
More informationT h e P h a n t o m L a b o r a t o r y
T h e P h a n t o m L a b o r a t o r y 1 CCT228 ATCM Phantom Manual Copyright 2017 WARRANTY THE PHANTOM LABORATORY INCORPORATED ( Seller ) warrants that this product shall remain in good working order
More informationExposure System Selection
Principles of Imaging Science II (RAD120) Exposure Systems Exposure System Selection Radiographic exposure is a very complex process Best technique systems manipulate one variable while holding others
More informationAppropriate Inspection Distance of Digital X-Ray Imaging Equipment for Diagnosis
Indian Journal of Science and Technology Vol 8(S8), 380-386, April 2015 ISSN (Print) : 0974-6846 ISSN (Online) : 0974-5645 DOI: 10.17485/ijst/2015/v8iS8/70528 Appropriate Inspection Distance of Digital
More informationClinical Experience Using the Open Bore Multislice CT System Supria (16 slice CT) MEDIX VOL. 61 P.8 P.11
Clinical Experience Using the Open Bore Multislice CT System Supria (16 slice CT) Hiroki Kadoya Yukiko Kitagawa MEDIX VOL. 61 P.8 P.11 Clinical Experience Using the Open Bore Multislice CT System Supria
More information3/31/2011. Objectives. Emory University. Historical Development. Historical Development. Historical Development
Teaching Radiographic Technique in a Digital Imaging Paradigm Objectives 1. Discuss the historical development of digital imaging. Dawn Couch Moore, M.M.Sc., RT(R) Assistant Professor and Director Emory
More informationIterative Reconstruction in Image Space. Answers for life.
Iterative Reconstruction in Image Space Answers for life. Iterative Reconstruction in Image Space * (IRIS) * Please note: IRIS is used as an abbreviation for Iterative Reconstruction in Image Space throughout
More informationCOMPUTED TOMOGRAPHY 1
COMPUTED TOMOGRAPHY 1 Why CT? Conventional X ray picture of a chest 2 Introduction Why CT? In a normal X-ray picture, most soft tissue doesn't show up clearly. To focus in on organs, or to examine the
More informationPD233: Design of Biomedical Devices and Systems
PD233: Design of Biomedical Devices and Systems (Lecture-8 Medical Imaging Systems) (Imaging Systems Basics, X-ray and CT) Dr. Manish Arora CPDM, IISc Course Website: http://cpdm.iisc.ac.in/utsaah/courses/
More informationTranslating Protocols Between Scanner Manufacturer and Model
Translating Protocols Between Scanner Manufacturer and Model Robert J. Pizzutiello, MS, FAAPM, FACMP Sr. Vice-President, Global Physics Solutions President, Upstate Medical Physics Objectives Understand
More informationCOMPUTED RADIOGRAPHY CHAPTER 4 EFFECTIVE USE OF CR
This presentation is a professional collaboration of development time prepared by: Rex Christensen Terri Jurkiewicz and Diane Kawamura New Technology https://www.youtube.com/watch?v=ptkzznazb 7U COMPUTED
More informationDiffraction-enhanced X-ray Imaging (DEXI) Medical Solutions. More information using less radiation
Diffraction-enhanced X-ray Imaging (DEXI) Medical Solutions More information using less radiation Medical Small Animal Security NDE/NDT Diffraction-Enhanced X-ray Imaging Medical Solutions Safe non-invasive
More informationSTEREOTACTIC BREAST BIOPSY EQUIPMENT SURVEYS
STEREOTACTIC BREAST BIOPSY EQUIPMENT SURVEYS JAMES A. TOMLINSON, M.S. Diagnostic Radiological Physicist American Board of Radiology Certified Medical Physics Consultants, Inc. Bio 28 yrs experience 100%
More informationSAFIRE. Sinogram Affirmed Iterative Reconstruction. Answers for life.
Neuro Thoracic Abdominal Abdominal Cardiovascular Pediatric SAFIRE Sinogram Affirmed Iterative Reconstruction Answers for life. SAFIRE * (Sinogram Affirmed Iterative Reconstruction) * The information
More information8/2/2017. Radiologist Responsibilities. Radiologist Responsibilities. Medical Physicist Mammography Equipment Evaluation and Annual Survey
Implementation of the 2016 ACR Digital Mammography QC Manual Medical Physicist Mammography Equipment Evaluation and Annual Survey Eric A Berns, PhD, FACR Radiologist Responsibilities Radiologist Responsibilities
More information12/21/2016. Siemens Medical Systems Research Agreement Philips Healthcare Research Agreement AAN and ASN Committees
Joseph V. Fritz, PhD Nandor Pintor, MD Dent Neurologic Institute ASN 2017 Friday, January 20, 2017 Siemens Medical Systems Research Agreement Philips Healthcare Research Agreement AAN and ASN Committees
More informationComparison of computed radiography and filmõscreen combination using a contrast-detail phantom
JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 4, NUMBER 1, WINTER 2003 Comparison of computed radiography and filmõscreen combination using a contrast-detail phantom Z. F. Lu,* E. L. Nickoloff, J.
More informationIntroduction. Sam R. Kottamasu Lawrence R. Kuhns
Pediatr Radiol (1997) 27: 119 123 Springer-Verlag 1997 Sam R. Kottamasu Lawrence R. Kuhns Musculoskeletal computed radiography in children: scatter reduction and improvement in bony trabecular sharpness
More informationPractical Medical Physics Session: TG-151 Dose Monitoring. August 5, 2013 Katie Hulme, M.S.
Practical Medical Physics Session: TG-151 Dose Monitoring August 5, 2013 Katie Hulme, M.S. Digital Imaging and Dose Creep Images courtesy of Agfa Healthcare Under-Exposed Over-Exposed Freedman et al.,
More informationBeam-Restricting Devices
Beam-Restricting Devices Three factors contribute to an increase in scatter radiation: Increased kvp Increased Field Size Increased Patient or Body Part Size. X-ray Interactions a some interact with the
More informationNuclear Associates
Nuclear Associates 07-649 CDRH Fluoroscopic Phantom Users Manual March 2005 Manual No. 07-649-1 Rev. 2 2004, 2005 Fluke Corporation, All rights reserved. Printed in U.S.A. All product names are trademarks
More informationAcceptance Testing of a Digital Breast Tomosynthesis Unit
Acceptance Testing of a Digital Breast Tomosynthesis Unit 2012 AAPM Spring Clinical Meeting Jessica Clements, M.S., DABR Objectives Review of technology and clinical advantages Acceptance Testing Procedures
More informationPATIENT EFFECTIVE DOSES IN DIAGNOSTIC RADIOLOGY, NA
Title of Paper: Patient effective doses in diagnostic radiology Authors: N.A. Gkanatsios, and W. Huda * Corresponding Author: Department of Radiology, University of Florida, P.O. Box 100374, Gainesville,
More informationabc MHRA Philips Mx8000 IDT CT scanner technical evaluation September 2004 Best choice best practice nww.medical-devices.nhs.
abc September 2004 MHRA 04099 Philips Mx8000 IDT CT scanner technical evaluation Best choice best practice www.mhra.gov.uk nww.medical-devices.nhs.uk About MHRA evaluation reports. What you can expect.
More informationOutline. Digital Radiography. Understanding Digital Modalities: Image Quality and Dose. Image Quality. Dose Control
Understanding Digital Modalities: Image Quality and Dose S. Jeff Shepard, M.S. University of Texas M. D. Anderson Cancer Center Houston, Texas Special Acknowledgement: Stephen K. Thompson, M.S. William
More informationNeuViz 16 Computed Tomography. Elevating routine imaging for exceptional results
NeuViz 16 Computed Tomography Elevating routine imaging for exceptional results Essence NeuViz 16 Raising the bar on clinical utility in routine imaging. Get more. More clinical information for patients.
More informationVeterinary Science Preparatory Training for the Veterinary Assistant. Floron C. Faries, Jr., DVM, MS
Veterinary Science Preparatory Training for the Veterinary Assistant Floron C. Faries, Jr., DVM, MS Radiology Floron C. Faries, Jr., DVM, MS Objectives Determine the appropriate machine settings for making
More informationNuclear Associates , , CT Head and Body Dose Phantom
Nuclear Associates 76-414,76-414-4150,76-415 CT Head and Body Dose Phantom Users Manual March 2005 Manual No. 76-414-1 Rev. 2 2004, 2005 Fluke Corporation, All rights reserved. Printed in U.S.A. All product
More informationOverview. Professor Roentgen was a Physicist!!! The Physics of Radiation Oncology X-ray Imaging
The Physics of Radiation Oncology X-ray Imaging Charles E. Willis, Ph.D. DABR Associate Professor Department of Imaging Physics The University of Texas M.D. Anderson Cancer Center Houston, Texas Overview
More informationNuclear Associates
Nuclear Associates 76-700 Digital Subtraction Angiography Phantom Users Manual March 2005 Manual No. 76-700-1 Rev. 2 2004, 2005 Fluke Corporation, All rights reserved. Printed in U.S.A. All product names
More informationQUANTITATIVE COMPUTERIZED LAMINOGRAPHY. Suzanne Fox Buchele and Hunter Ellinger
QUANTITATIVE COMPUTERIZED LAMINOGRAPHY Suzanne Fox Buchele and Hunter Ellinger Scientific Measurement Systems, Inc. 2201 Donley Drive Austin, Texas 78758 INTRODUCTION Industrial computerized-tomography
More informationImprovement of CT image quality with iterative reconstruction idose4
Improvement of CT image quality with iterative reconstruction idose4 Poster No.: C-0387 Congress: ECR 2014 Type: Scientific Exhibit Authors: M.-L. Olsson, K. Norrgren, M. Söderberg; Malmö/SE Keywords:
More informationCT radiation profile width measurement using CR imaging plate raw data
JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 16, NUMBER 6, 2015 CT radiation profile width measurement using CR imaging plate raw data Thorarin A Bjarnason, 1,2,3a Chang-Ying Joseph Yang 3,4 Diagnostic
More informationThe Evaluation of Collimator Alignment of Diagnostic X-ray Tube Using Computed Radiography System
The Evaluation of Collimator Alignment of Diagnostic X-ray Tube Using Computed Radiography System The Evaluation of Collimator Alignment of Diagnostic X-ray Tube Using Computed Radiography System Manus
More informationDOSELAB TOMOTHERAPY TG-148 QA QUICK GUIDE TG-148 RECOMMENDED TESTS 1. V.B.1.C. - Y-JAW DIVERGENCE/BEAM CENTERING
DOSELAB TOMOTHERAPY TG-148 QA QUICK GUIDE Rev. 1.0 DOSELAB TOMOTHERAPY TG-148 QA QUICK GUIDE DoseLab users may reference the following instructions to perform Tomotherapy Quality Assurance tests as recommended
More informationMaximum Performance, Minimum Space
TECHNOLOGY HISTORY For over 130 years, Toshiba has been a world leader in developing technology to improve the quality of life. Our 50,000 global patents demonstrate a long, rich history of leading innovation.
More information2D, 3D CT Intervention, and CT Fluoroscopy
2D, 3D CT Intervention, and CT Fluoroscopy SOMATOM Definition, Definition AS, Definition Flash Answers for life. Siemens CT Vision Siemens CT Vision The justification for the existence of the entire medical
More informationHalf value layer and AEC receptor dose compliance survey in Estonia
Half value layer and AEC receptor dose compliance survey in Estonia K. Kepler, A. Vladimirov Training Centre of Medical Physics, University of Tartu Testing Centre of the University of Tartu, Estonia E-mail:
More informationCT Basics: Data Acquisition Module 3
Module 3 Transcript For educational and institutional use. This transcript is licensed for noncommercial, educational inhouse or online educational course use only in educational and corporate institutions.
More informationA comparative study of several digital flat panel X-ray units: patients doses and image quality in chest radiography
A comparative study of several digital flat panel X-ray units: patients doses and image quality in chest radiography Torres Cabrera R. 1, España López M.L. 2 Ruiz Manzano P. 3, Sastre Aguado J.M. 4,, Rivas
More informationAutomated Technique to Measure Noise in Clinical CT Examinations
Medical Physics and Informatics Original Research Christianson et al. Noise Measurement in Clinical CT Medical Physics and Informatics Original Research Downloaded from www.ajronline.org by 46.3.195.17
More informationSECTION I - CHAPTER 2 DIGITAL IMAGING PROCESSING CONCEPTS
RADT 3463 - COMPUTERIZED IMAGING Section I: Chapter 2 RADT 3463 Computerized Imaging 1 SECTION I - CHAPTER 2 DIGITAL IMAGING PROCESSING CONCEPTS RADT 3463 COMPUTERIZED IMAGING Section I: Chapter 2 RADT
More informationA study of exposure index value fluctuations in computed radiography and direct digital radiography using multiple manufacturers
A study of exposure index value fluctuations in computed radiography and direct digital radiography using multiple manufacturers Poster No.: C-3011 Congress: ECR 2010 Type: Topic: Authors: Scientific Exhibit
More informationInstant DR in Jordan
Hashemite University leads the way with first Instant DR in Jordan DR Retrofit supports research and education goals of the Faculty of Allied Health Sciences, while enhancing care for staff and students
More informationNew Exposure Indicators for Digital Radiography Simplified for Radiologists and Technologists
Medical Physics and Informatics Technical Innovation Don et al. New Simplified Exposure Indicators Medical Physics and Informatics Technical Innovation Steven Don 1 ruce R. Whiting 2 Lois Jo Rutz 3 ruce
More informationLudlum Medical Physics
Ludlum Medical Physics Medical Imaging Radiology QA Test Tools NEW LUDLUM PRODUCT LINE Medical Physics Products Medical Physics Products What are they? Products used to measure radiation output and to
More information