Half-value Layer Measurements Research Articles

Evaluation of the measurement accuracy and uncertainty of a solid-state detector under diagnostic x-ray beam conditions.

An accurate measurement of x-ray beams is expected to reduce the uncertainties associated with estimating radiation risk to patients in clinical settings. To perform assessment tasks based on the readings of a solid-state detector (SSD) using semiconductor technology, the characteristics of the detector should be elucidated. In this study, we evaluated the measurement accuracy of a new SSD under diagnostic x-ray beam conditions in terms of air kerma, tube voltage, and half-value layer (HVL). The performance of the SSD was then compared with those of reference instruments. The tube voltage was varied within the range of 50-120kV in steps of 10kV and the thickness and materials of additional filters were concurrently changed (several combinations were tested). In addition, the dose rate and energy dependence of the SSD were also investigated. These effects were analyzed based on statistical significance tests. Furthermore, the expanded uncertainties in the series of measurements were meticulously calculated. The results showed average relative differences of -3.26±1.33%, 0.44±1.01%, and -2.60±3.31% for air kerma, tube voltage, and HVL, respectively. Furthermore, air kerma did not exhibit any dependence on dose rate and energy, in contrast to tube voltage and HVL measurements. The measurement values of the SSD fall within the acceptable range of uncertainty, highlighting its measurement accuracy and reliability. Furthermore, based on the characteristics elucidated by this study, valuable insights are provided concerning the assurance of appropriate measurement values in clinical settings.

Influence of anode/filtration setup on X-ray multimeter energy response in mammography applications

Quality control and assurance of mammography X-ray generators include the use of solid-state detectors and/or ionization chambers calibrated in standard reference radiation fields. The IEC 61267:2005 standard defines reference mammography radiation fields for Mo/Mo anode/filtration, while various anode/filtration combinations are encountered in clinical mammography X-ray units. Not all Secondary Standard Dosimetry Laboratories have an X-ray generator with Mo/Mo radiation setup. Thus, traceability can be established only for the available anode/filter combinations, commonly limited to W/Al. In this study, W/Al radiation fields were established under laboratory conditions by performing half-value layer measurements. Then, four solid-state detectors were characterized. X-ray multimeter performance was evaluated in terms of energy response in the W/Al radiation fields. In the laboratory conditions, the energy response of the dosimeters had a large deviation from unity for dosimeters without appropriate anode/filter combination selected in the software settings, even though most of the dosimeters had a uniform relative response. The discrepancy in the response was further investigated by examining its variation induced by available detector software settings, and it was determined that the dosimeter response can vary up to 20 %. In a clinical setup, the half-value layer was determined, and detector performance was examined. Dosimeters were tested in clinical fields with Mo/Mo, Mo/Rh, W/Rh, W/Ag anode/filter combinations in the X-ray tube voltage range from 25 kV to 35 kV. For most clinical radiation fields, multi-element detectors had energy response deviation within ±5 %. The single-element detector had one software setting available and exhibited strong energy dependence. Extensive testing of detector response, such as presented in this paper. allows for correction factor interpolation based on the half-value layer.

Half-value layer measurements using solid-state detectors and single-rotation technique with lead apertures in spiral computed tomography with and without a tin filter.

Solid-state detectors (SSDs) may be used along with a lead collimator for half-value layer (HVL) measurement using computed tomography (CT) with or without a tin filter. We aimed to compare HVL measurements obtained using three SSDs (AGMS-DM+ , X2 R/F sensor, and Black Piranha) with those obtained using the single-rotation technique with lead apertures (SRTLA). HVL measurements were performed using spiral CT at tube voltages of 70-140kV without a tin filter and 100-140kV (Sn 100-140kV) with a tin filter in increments of 10kV. For SRTLA, a 0.6-cc ionization chamber was suspended at the isocenter to measure the free-in-air kerma rate ( ) values. Five apertures were made on the gantry cover using lead sheets, and four aluminum plates were placed on these apertures. HVLs in SRTLA were obtained from decline curves. Subsequently, SSDs inserted into the lead collimator were placed on the gantry cover and used to measure HVLs. Maximum HVL differences of AGMS-DM+ , X2 R/F sensor, and Black Piranha with respect to SRTLA without/with a tin filter were - 0.09/0.6 (only two Sn 100-110kV) mm, - 0.50/ - 0.6mm, and - 0.17/(no data available) mm, respectively. These values were within the specification limit. SSDs inserted into the lead collimator could be used to measure HVL using spiral CT without a tin filter. HVLs could be measured with a tin filter using only the X2 R/F sensor, and further improvement of its calibration accuracy with respect to other SSDs is warranted.

Accuracy of non-contact semiconductor X-ray analyzer for quality assurance in intraoral radiography: a comparison with ionization chamber dosimeter.

The aim of the present study was to evaluate the accuracy of a non-contact semiconductor X-ray analyzer for quality assurance in intraoral radiography, especially a comparison with an ionization chamber dosimeter. Intraoral radiography was performed with intraoral X-ray unit using the dental protocol at our hospital: tube voltage, 70kV; tube current, 7mA. Accuracy of dose and half-value layer (HVL) measurements was analyzed with a non-contact semiconductor X-ray analyzer and an ionization chamber dosimeter. Stability of the semiconductor sensor, effect of scattered radiation, and comparison of measured HVL between the ionization chamber and the semiconductor sensor were analyzed in this study. The values with the semiconductor sensor were tube voltage: 70.3 ± 0.2 kVp (degree of variability: 0.28%), dose: 454.1 ± 12.3μGy (degree of variability: 2.7%), and HVL: 1.91 ± 0.02 mmAl (degree of variability: 1.0%). With collimator, the dose with the semiconductor sensor and the ionization chamber decreased by 2.3 μ Gy and 5.2 μ Gy, respectively. The measured HVL of the semiconductor dosimeter was more than that of ionization chamber, and the semiconductor dosimeter was less than ionization chamber in variation of between without and with collimator. This study indicated the accuracy of a non-contact semiconductor X-ray analyzer for quality assurance in intraoral radiography, especially a comparison with an ionization chamber dosimeter. The semiconductor sensor can be useful for quality assurance in intraoral radiography.

A pilot study of half-value layer measurements using a semiconductor dosimeter for intraoral radiography.

This pilot study was conducted to evaluate half-value layer (HVL) measurements obtained using a semiconductor dosimeter for intraoral radiography. This study included 8 aluminum plates, 4 of which were low-purity (less than 99.9%) and 4 high-purity (greater than 99.9%). Intraoral radiography was performed using an intraoral X-ray unit in accordance with the dental protocol at the authors' affiliated hospital: tube voltage, 60 kVp and 70 kVp; tube current, 7 mA; and exposure time, 0.10 s. The accuracy of HVL measurements for intraoral radiography was assessed using a semiconductor dosimeter. A simple regression analysis was performed to compare the aluminum plate thickness and HVL in relation to the tube voltage (60 kVp and 70 kVp) and aluminum purity (low and high). For the low-purity aluminum plates, the HVL at 60 kVp (Y) and 70 kVp (Y) was significantly correlated with the thickness of the aluminum plate (X), with Y = 1.708 + 0.415X (r=0.999, P<0.05) and Y = 1.980 + 0.484X (r=0.999, P<0.05), respectively. Similarly, for the high-purity aluminum plates, the HVL at 60 kVp (Y) and 70 kVp (Y) was significantly correlated with the plate thickness (X), with Y = 1.696 + 0.454X (r=0.999, P<0.05) and Y = 1.968 + 0.515X (r=0.998, P<0.05), respectively. This pilot study examined the relationship between aluminum plate thickness and HVL measurements using a semiconductor dosimeter for intraoral radiography. Semiconductor dosimeters may prove useful in HVL measurement for purposes such as quality assurance in dental X-ray imaging.

Measurement of Average Glandular Dose Using Multiparameter X-ray Measuring Instrument

The average glandular dose (AGD) is very important in the quality control of mammography. The AGD calculation requires measurements of half-value layer (HVL) and entrance surface air karma (ESAK). The HVL is measured by the Al-attenuation method using a non-energy-dependent ionization dosimeter. As the Al-attenuation method performs measurements using a succession of added filters, it requires lots of X-ray exposure and measurement time. In recent years, measuring instruments that can measure tube voltage, irradiation time, exposure dose, HVL, and other factors, at the same time, using one shot of X-rays have been developed. In this study, measurement of the AGD using multiparameter X-ray measuring instrument about rhodium (Rh) and tungsten (W) anode X-ray tubes. A comparative study was performed using standard ionization dosimeters. The error in measurements was as follows: HVL 5.8%, ESAK 3.3%, and AGD 2.9%. The AGD measurement using a multiparameter X-ray measuring instrument is simple and can significantly reduce the measurement time while maintaining accuracy.

Machine characterization and central axis depth dose data of a superficial x-ray radiotherapy unit

Objectives. The purpose of this study is to present data from the clinical commissioning of an Xstrahl 150 x-ray unit used for superficial radiotherapy, Methods. Commissioning tasks included vendor acceptance tests, timer reproducibility, linearity and end-effect measurements, half-value layer (HVL) measurements, inverse square law verification, head-leakage measurements, and beam output calibration. In addition, percent depth dose (PDD) curves were determined for different combinations of filter/kV settings and applicators. Automated PDD water phantom scans were performed utilizing four contemporary detectors: a microDiamond detector, a microSilicon detector, an EDGE detector, and a PinPoint ionization chamber. The measured PDD data were compared to the published values in BJR Supplement 25, Results. The x-ray unit’s mechanical, safety, and radiation characteristics were within vendor-stated specifications. Across sixty commissioned x-ray beams, the PDDs determined in water using solid state detectors were in excellent agreement with the BJR 25 data. For the lower (<100 kVp) and medium-energy (≥100 kVp) superficial beams the average agreement was within [−3.6,+0.4]% and [−3.7,+1.4]% range, respectively. For the high-energy superficial (low-energy orthovoltage) x-rays at 150 kVp, the average difference for the largest 20 × 20 cm2 collimator was (−0.7 ± 1.0)%, Conclusions. This study presents machine characterization data collected for clinical use of a superficial x-ray unit. Special focus was placed on utilizing contemporary detectors and techniques for the relative PDD measurements using a motorized water phantom. The results in this study confirm that the aggregate values published in the BJR 25 report still serve as a valid benchmark when comparing data from site-specific measurements, or the reference data for clinical utilization without such measurements, Advances in knowledge. This paper presents comprehensive data from the acceptance and commissioning of a modern kilovoltage superficial x-ray radiotherapy machine. Comparisons between the PDD data measured in this study using different detectors and BJR 25 data are highlighted.

Radiation doses in the United Kingdom breast screening programmes 2016-2019.

To record the radiation doses involved in UK breast screening and to identify any changes since previous publications related to technical factors and the population screened. Mammographic exposure factors for 68,998 women imaged using 411 X-ray sets spread across the UK were compiled. Local output and half value layer measurements for each X-ray set were used to estimate mean glandular dose (MGD) using the standard UK method. Mean MGDs in digital mammography have increased by 11% since 2010-12 for both medio-lateral oblique (MLO) and cranio-caudal (CC) views. The mean compressed breast thickness (CBT) has increased (4.8% CC, 5.2% MLO) over the same period. The mean MLO CBT value of 62.4 ± 0.1 mm is outside the 50 to 60 mm range used for diagnostic reference levels. The increase in MGD is consistent with the CBT changes. The mean MGD in the 50 to 60 mm CBT range is 1.44 ± 0.03 mGy for MLO views. CBT varies with age and peaks at 51. Mean CBT has increased with time, and this has increased mean MGDs for digital mammography. CBT also varies with age. Updated average MGDs in the UK are provided. There is evidence that breast size is increasing in the UK and that mean CBT is affected by age-related changes in the breast.

Use of calculations to validate beam quality and relative dose measurements for a kilovoltage X-ray therapy unit.

Relative dosimetry measurements are required to fully commission kilovoltage X-ray units for superficial and orthovoltage X-ray therapy. Validation of these relative dosimetry measurements with Monte Carlo methods is advantageous being independent of the measurement process. In this study use is made of the X-ray spectrum generating program SpekPy along with the EGSnrc Monte Carlo code to calculate depth doses and explore the dosimetry effect of changes in backscatter. These calculations are compared with previously reported measurements for the Pantak SXT 150 X-ray therapy unit. SpekPy can also be used to generate half value layer (HVL) values and these are also compared to previously reported HVL measurements for the same X-ray therapy unit. It was found that agreements of the order of 5% in HVL, 3% in depth dose and 1% in backscatter doses were found between Monte Carlo calculations and the previously published measured data. Exit doses in conditions of lack of full backscatter were explored with Monte Carlo calculations demonstrating reduced exit dose up to 20% in these conditions. It is concluded that SpekPy with Monte Carlo codes such as EGSnrc provides a straightforward approach to validating various relative dosimetry measurements in kilovoltage X-ray dosimetry.

Experiment of a Dedicated Lead Slit for X-ray Output Analyzer in X-ray CT Half-value Layer Measurements

It is not easy to measure the half-value layer (HVL) of CT because it is necessary to place the X-ray tube position fixed. The aim of this study was to experiment the new methods of HVL measuring of CT using a custom-made lead slit. The custom-made lead slit method allowed the HVL measuring of CT while the rotation of the X-ray tube. The error of HVL value using the custom-made lead slit method compared to the conventional method was within 6%. The custom-made lead slit method can enable to measure the HVL of CT easily without the X-ray tube position fixed.

Evaluation of Surface Dose and Commissioning of Compensator-Based Total Body Irradiation.

Purpose:The aim of the current study is to commission compensator-based total body irradiation (TBI) and to compare surface dose using percentage depth dose (PDD) while varying the distance between beam spoiler and phantom surface.Materials and Methods:TBI commissioning was performed on Elekta Synergy® Platform linear accelerator for bilateral extended source to surface distance treatment technique. The PDD was measured by varying the distance (10 cm, 20 cm, 30 cm, and 40 cm) between the beam spoiler and the phantom surface. Beam profile and half-value layer (HVL) measurement were carried out using the FC65 ion-chamber. Quality assurance (QA) was performed using an in-house rice-flour phantom (RFP). In-vivo diodes (IVD) were placed on the RFP at various regions to measure the delivered dose, and it was compared to the calculated dose.Results:An increase in Dmax and surface dose was observed when beam spoiler was moved away from the phantom surface. The flatness and symmetry of the beam profile were calculated. The HVL of Perspex and aluminum is 17 cm and 8 cm, respectively. The calculated dose of each region was compared to the measured dose on the RFP with IVD, and the findings showed that the variation was <4.7% for both Perspex and Aluminum compensators.Conclusion:The commissioning of the compensator-based TBI technique was performed and its QA measurements were carried out. The Mayneord factor corrected PDD and measured PDD values were compared. The results are well within the clinical tolerance limit. This study concludes that 10 cm −20 cm is the optimal distance from the beam spoiler to phantom surface to achieve prescribed dose to the skin.

Accuracy of HVL measurements utilizing solid state detectors for radiography and fluoroscopy X-ray systems.

The half‐value layer (HVL) is one of the regulatory required radiation safety parameters that needs to be measured annually. With the advent of solid state detectors and their associated electrometer assembly, the HVL measurement can be conducted with relative ease. In fact, various radiological technique parameters such as tube potential (kV), exposure time in millisecond (msec), air kerma (mGy), and air kerma rate (mGy/sec) can be obtained along with the HVL with just one exposure. The measured (or, calculated) HVL is based on radiation detection systems calibrated for conventional x‐ray systems equipped with tungsten anode and added aluminum filters (molybdenum anode and filter in the case of mammography systems). However, a new generation of radiography and fluoroscopy (R/F) systems, inclusive of interventional angiography equipment, is equipped with varying thicknesses and materials of spectral shaping filters (SSF) to minimize the radiation exposure to the patients while image quality is maintained and optimized. The accuracy of HVL obtained with new generation of R/F systems has not been investigated in depth due to the addition of spectral filters yielding a harder beam quality with a higher HVL than the regulatory required value of 2.9 mm Al HVL at 80 kV. It would be of great interest to determine the accuracy of HVL as measured (or, calculated) by the solid state detector systems (SSDS), especially when accurate radiation dose delivered to the patient is required. In this investigation, the subject is limited to the accuracy of HVL measurement for conventional R/F systems.

Characterization of arterial plaque composition with dual energy computed tomography: a simulation study.

To investigate the feasibility of quantifying the chemical composition of coronary artery plaque in terms of water, lipid, protein, and calcium contents using dual-energy computed tomography (CT) in a simulation study. A CT simulation package was developed based on physical parameters of a clinical CT scanner. A digital thorax phantom was designed to simulate coronary arterial plaques in the range of 2-5mm in diameter. Both non-calcified and calcified plaques were studied. The non-calcified plaques were simulated as a mixture of water, lipid, and protein, while the calcified plaques also contained calcium. The water, lipid, protein, and calcium compositions of the plaques were selected to be within the expected clinical range. A total of 95 plaques for each lesion size were simulated using the CT simulation package at 80 and 135 kVp. Half-value layer measurements were made to make sure the simulated dose was within the range of clinical dual energy scanning protocols. Dual-energy material decomposition using a previously developed technique was performed to determine the volumetric fraction of water, lipid, protein, and calcium contents in each plaque. For non-calcified plaque, the total volume conservation provides the third constrain for three-material decomposition with dual energy CT. For calcified plaque, a fourth criterion was introduced from a previous report suggesting a linear correlation between water and protein contents in soft tissue. For non-calcified plaque, the root mean-squared error (RMSE) of the image-based decomposition was estimated to be 0.7%, 1.5%, and 0.3% for water, lipid, and protein contents, respectively. As for the calcified plaques, the RMSE of the 5mm plaques were estimated to be 5.6%, 5.7%, 0.2%, and 3.1%, for water, lipid, calcium, and protein contents, respectively. The RMSE increases as the plaque size reduces. The simulation results indicate that chemical composition of coronary arterial plaques can be quantified using dual-energy CT. By accurately quantifying the content of a coronary plaque lesion, our decomposition method may provide valuable insight for the assessment and stratification of coronary artery disease.

Measurement of the half-value layer for CT systems in a single-rotation technique: Reduction of stray radiation with lead apertures

PurposeThis study aimed to compare two methods of assessing the half-value layer (HVL) for computed tomography scanners in a single-rotation technique with and without lead apertures (SRTLA / SRT). MethodsA 0.6 cc real-time ionization chamber was suspended freely in the air at the isocenter, and six sheets of lead (130 × 170 × 2 mm) were placed at the bottom of the gantry cover, forming five apertures each having a width of 16 mm (SRTLA geometry). Four aluminum plates (100 × 100 mm2; 2.0, 4.0, 6.0, and 8.0 mm thick) were placed on these apertures. Air-kerma rate profiles (K̇air) in the spiral mode were measured at tube potentials of 80, 100, 120, and 135 kVp, a tube current of 100 mA, a nominal beam width of 32.0 mm, and a rotation time of 1.5 s. Thereafter, all lead sheets were removed, and these same measurements were taken to investigate the errors of the HVLs (SRT geometry). HVLs using the SRTLA and SRT were compared with those obtained through a conventional localization technique. ResultsThe HVLs measured in the SRTLA/SRT at 80, 100, 120, and 135 kVp were 3.37/3.50, 4.24/4.47, 5.22/5.44, and 5.90/6.17 mm, respectively. The differences between these values and those obtained through the conventional technique were 0.09/0.22, 0.02/0.25, 0.05/0.27, and −0.01/0.26 mm, respectively. ConclusionsThe accuracies of the HVLs of the SRTLA were similar to those of the conventional technique. The lead apertures under the aluminum plates would help reduce the number of inaccurate HVL measurements.

Performance of semiconductor dosimeters with a range of radiation qualities used for mammography: A calibration laboratory study.

PurposeTo investigate the radiation quality dependence of the response of commercial semiconductor‐based dosimeters, and to estimate potential errors and uncertainties related to different measurement and calibration scenarios.MethodsAll measurement results were compared to reference values measured at the IAEA dosimetry laboratory which is traceable to the international system of units (SI). Energy dependence of the response of eight semiconductor dosimeters were determined for five different anode‐filter combinations and tube voltages from 25 to 35 kV. For systems capable of deriving half value layer (HVL) and tube voltage from measurements, calibration coefficients for these measurements were calculated.ResultsFor six dosimeters, the maximum deviations from the reference value of the air kerma measurement were within ±5% as required by IEC 61674. Calibration coefficients for radiation qualities (anode‐filter and tube voltage combinations) relative to reference radiation quality Mo‐Mo 28 kV deviate up to 12%. HVL and tube voltage measurements exhibited deviations up to 11% and 10%, respectively.ConclusionsThe air kerma responses of modern semiconductor dosimeters have a small energy dependence. However, no dosimeter tested complied with the accuracy limits stated by the manufacturer for tube voltage measurements, and only two dosimeters complied with the limits for HVL measurements. Absolute measurement of HVL and tube voltage with semiconductor dosimeters have to be verified for actual clinical radiation conditions on clinical mammography systems. Semiconductor dosimeters can be used for quality control measurements if individual calibration coefficients are available for the radiation condition applied. If other conditions are applied, additional uncertainty needs to be considered, particularly in the case of HVL and tube voltage measurements.

Mammography Dose Survey Using International Quality Standards

Digital mammography is the current standard for breast cancer screening. The absence of any dosimetric data, the quality standards, and the fear of radiation detriment, sometimes, hampers the smooth introduction of this technology and the launch of breast cancer screening programmes. As the breast cancer screening programmes are in development in Morocco, quality standards have been set in this study, so that any new breast cancer screening service could get started with their first analysis. The purpose of this study was to report the first Moroccan breast dose and to test quality standards compared with European guidelines. A dosimetric study is conducted by calculating mean glandular dose (MGD) for patients' breasts and polymethyl methacrylate (PMMA) for each thickness from recorded radiographic factors and X-ray tube (output and half-value layer) measurements using Dance's model for a digital mammography system. This is carried out to determine the correlation between phantom and patient measurements.The mean MGD for patient data was 1.02 ± 0.5 mGy and the compressed breast thickness was 55 ± 14 mm. For compressed breast thickness range of 50–60 mm, the MGD was 0.94 ± 0.3 mGy and the dose calculated with PMMA phantom for the same range thickness was 1.33 mGy. The results of MGD as a function of PMMA thickness is lower than the achievable limit curve proposed in the European guidelines. The average doses, which depend on the technical parameters of the mammography equipment, are in line with values obtained in European guidelines. In addition, an investigation is needed throughout the Moroccan territory, in the sense of optimization of radiological practices and techniques in mammographic centres aligning with the international recommendations.

Reference X-ray Irradiation System for Personal Dosimeter Testing and Calibration of Radiation Detector

Background: In the calibration and testing laboratory of Korea Atomic Energy Research Institute, the old X-ray generator used for the production of reference X-ray fields was replaced with a new one. For this newly installed X-ray irradiation system, beam alignment as well as the verification of beam qualities was conducted. Materials and Methods: The existing X-ray generator, Phillips MG325, was replaced with YXLON Y.TU 320-D03 in order to generate reference X-ray fields. Theoretical calculations and Monte Carlo simulations were used to determine initial filter thickness. Beam alignment was performed in three steps to deliver a homogeneous radiation dosage to the target at different distances. Finally, the half-value layers were measured for different X-ray fields to verify beam qualities by using an ion chamber. Results and Discussion: Beam alignment was performed in three steps, and collimators and other components were arranged to maintain the uniformity of the mean air kerma rate within ±2.5% at the effective beam diameter of 28 cm. The beam quality was verified by using halfvalue layer measurement methods specified by American National Standard Institute (ANSI) N13.11-2009 and International Organization for Standardization (ISO)-4037. For each of the nine beams than can be generated by the new X-ray irradiation system, air kerma rates for Xray fields of different beam qualifies were measured. The results showed that each air kerma rate and homogeneity coefficient of the first and second half-value layers were within ±5% of the recommended values in the standard documents. Conclusion: The results showed that the new X-ray irradiation system provides beam qualities that are as high as moderate beam qualities offered by National Institute of Standards and Technology in ANSI N13.11-2009 and those for narrow-spectrum series of ISO-4037.

Evaluation of the Quality Control and Quality Assurance in Mammography mobile Unit

The aim of this study was to undertake a comprehensive evaluation of selected mammography unit. The materials used mammography machine Philips, multi-electrometer, target and filter combinations W/Rh, Mo/Rh and Mo/Mo and Aluminum layers. The quality control assessment was performed on the selected machine. The assessment was done included kV accuracy and reproducibility and Half Value Layer measurement. The results obtained confirmed that the machine is workingcorrectly and was within acceptable performance criteria. The results of the physical parameters indicated a deviation of tube potential for the examined tube from the nominal values with the standard deviation (± 5%), except the few values exceeds this levels, and the conclusion is that some adjustments showed be done and the have value layer at the nominal tube potential (28kV) was in agreement with the published values.

A study of one-shot half-value layer measurement for diagnostic X-ray equipment daily quality control

A study of one-shot half-value layer measurement for diagnostic X-ray equipment daily quality control

Determination of Half Value Layer (HVL) Value on X-Rays Radiography with using Aluminum, Copper and Lead (Al, Cu, and Sn) Attenuators

Half Value Layer (HVL) has done on X-rays using Aluminum (Al), Copper (Cu) and Tin (Sn) at University Hospital of North Sumatera. The method used is based on BAPETEN Regulation No.09 of 2011 and Standard Western Australia. From the results of research conducted on X-ray plane obtained the result of measurement of Half Value Layer (HVL) value by using Aluminum (Al) at 50 kVp - 90 kVp, with strong current of 20 mAs, obtained HVL thickness on Aluminum 50 kVp = 3.0 mm Al, 60 kVp = 4.0 mm Al, 70 kVp = 5.0 mm Al, 81 kVp = 5.6 mm Al and 90 kVp = 6.1 mm Al. By using Copper (Cu) at a voltage of 50 kVp = 0.05 mm Cu, 60 kVp = 0.15 mm Cu, 70 kVp = 0.2 mm Cu, 81 kVp = 0.3 mm Cu and 90 kVp = 0.3 mm Cu. By using Tin (Sn) at a voltage of 50 kVp = 0.05 mm Sn, 60 kVp = 0.05 mm Sn, 70 kVp = 0.05 mm Sn, 81 kVp = 0.05 mm Sn and 90 kVp = 0.05 mmSn. From the results of this study found that of the three types of attenuator, the best as an attenuator for Half Value layer (HVL) for X-ray plane is Aluminum (Al) and Copper (Cu). For Tin type Attenuator (Sn) is not suitable as an attenuator to measure HVL on an X-ray plane at a voltage of 50 kVp - 90 kVp.