Medical X-ray Films Research Articles

A medical waste X-ray film based triboelectric nanogenerator for self-powered devices, sensors, and smart buildings

Medical waste X-ray films are used to fabricate a triboelectric nanogenerator (TENG). The high-power density of (1.39 W m−2) TENG demonstrated its potential applications in self-powered devices, sensors, and smart buildings.

Towards the Experimental Assessment of the DQE in SPECT Scanners

The purpose of this work was to introduce the Detective Quantum Efficiency (DQE) in single photon emission computed tomography (SPECT) systems using a flood source. A Tc-99m-based flood source (Eγ = 140 keV) consisting of a radiopharmaceutical solution of dithiothreitol (DTT, 10-3 M)/Tc-99m(III)-DMSA, 40 mCi/40 ml bound to the grains of an Agfa MammoRay HDR Medical X-ray film) was prepared in laboratory. The source was placed between two PMMA blocks and images were obtained by using the brain tomographic acquisition protocol (DatScan-brain). The Modulation Transfer Function (MTF) was evaluated using the Iterative 2D algorithm. All imaging experiments were performed in a Siemens e-Cam gamma camera. The Normalized Noise Power spectra (NNPS) were obtained from the sagittal views of the source. The higher MTF values were obtained for the Flash Iterative 2D with 24 iterations and 20 subsets. The noise levels of the SPECT reconstructed images, in terms of the NNPS, were found to increase as the number of iterations increase. The behavior of the DQE was influenced by both MTF and NNPS. As the number of iterations was increased, higher MTF values were obtained, however with a parallel, increase of magnitude in image noise, as depicted from the NNPS results. DQE values, which were influenced by both MTF and NNPS, were found higher when the number of iterations results in resolution saturation. The method presented here is novel and easy to implement, requiring materials commonly found in clinical practice and can be useful in the quality control of SPECT scanners.

Clinical features and treatment strategy of ankle supination fractures in children

Objective To analyze the clinical characteristics and treatment strategy of ankle supination fracture in children. Methods From January 2012 through July 2014, 89 children were treated at our department for ankle fracture caused by supination sprain according to their medical history, physical examination, X-ray films and CT three-dimensional reconstruction of the ankle. Appropriate protocols were applied on the basis of Lauge-Hansen classification, type and displacement of their fractures. Of them, 52 belonged to the supination-adduction type (the extramalleolus fracture was of Odgen type Ⅶ in 51 children whose epiphyseal plate of distal fibula had not been closed) , 35 to the supination-extorsion type (32 cases had tri-plane fracture and 3 Tillaux fracture) , and the remaining 2 did not fit the Lauge-Hansen classification. Surgical treatment was applied in 32 cases and conservative treatment in 57 ones. Results All the children received outpatient follow-up from 12 to 24 months (mean, 18 months). No bone nonunion, osteoarthritis, or fracture malunion was found. The American Orthopaedic Foot & Ankle Society scores averaged 92 points (range, from 88 to 100 points) at the last follow-ups. Conclusions In children whose epiphyseal plate is nearly closed, supination-adduction sprain likely causes an extramalleolus fracture of Salter-Harris type Ⅰ or type Ⅱ, but in children whose epiphyseal plate is unclosed, an epiphyseal fracture of Odgen type Ⅶ is inclined to happen. A Tillaux fracture or tri-plane fracture at the level of distal tibiofibular syndesmosis results often from supination-extorsion sprain in children. For fractures involving epiphysis or epiphyseal plate, anatomical reduction and proper fixation are critical to functional recovery and reducing complications. Key words: Ankle joint; Fractures, bone; Epiphyseal plate; Ligament

Changes in Sensitometric Parameters of Medical X-Ray Films. Part 2: Evaluation Using Manual Processing

Results of evaluation of X-ray sensitometric parameters of the most common medical X-ray films upon manual processing are discussed. Analysis and appreciation of changes in the film parameters that have occurred in recent years are given.

Changes in Sensitometric Parameters of Medical X-Ray Films. Part 1: Evaluation Using Automatic Processing

The results of evaluation of X-ray sensitometric parameters of the most common medical X-ray films obtained by automatic film processing are discussed. In addition, the silver contents of the investigated emulsions are cited. Analysis and appreciation of changes in the film parameters that have occurred in recent years are given.

A novel easy-to-use phantom for the determination of MTF in SPECT scanners

To evaluate modulation transfer function (MTF) in single photon emission computed tomography (SPECT) systems using the line spread function (LSF) method and a novel flood source which can be easily fabricated with materials accessible in hospital facilities. A Tc-99m-based flood source (E(γ) = 140 keV) consisting of a radiopharmaceutical bound to the grains of a radiographic film was prepared in laboratory. Various films and radiopharmaceuticals were examined, in order to obtain a thin homogenous and reproducible flood source. The source showing best uniformity and reproducibility was placed between two PMMA blocks and images were obtained by using the brain tomographic acquisition protocol (brain) and the myocardial perfusion tomographic acquisition protocol (heart). MTF was evaluated by determining the LSF for various reconstruction methods and filters. MTF calculation was obtained by the utilization of a custom made software in which a method similar to the one proposed by Boone [Med. Phys. 28, 356-360 (2001)] was implemented. All imaging experiments were performed in a Siemens e-Cam γ-camera. Furthermore, MTF was assessed through the point spread function (PSF) following conventional methods. The optimum homogeneity was obtained by immersing an Agfa MammoRay HDR Medical x-ray film in a solution of dithiothreitol (DTT, 10(-3) M)/Tc-99m(III)-DMSA (DMSA: trivalent technetium-99m-dimercapto-succinic acid, 40 mCi/40 ml) for 30 min in the dark. These films exhibited better uniformity (CV < 1.9%). Higher MTF values were obtained for the brain scan protocol with iterative 3D with eight iterations reconstruction method. MTF of the brain protocol was in all cases better than the heart protocol. MTFs derived from LSF were more precise compared with those obtained from PSF since their reproducibility was better in all cases, providing a mean standard deviation of 0.0065, in contrary to the PSF method which gave 0.0348. The method presented here is novel and easy to implement, requiring materials commonly found in clinical practice. Furthermore, this technique which is based on the LSF method reduces measurement noise levels due to the larger amount of data averaging than in the conventional PSF method. Furthermore, MTF can be assessed easily, in three dimensions (3D), by placing the flood source either in sagittal or coronal direction.

Design of Image Quality in Medical X-Ray Film

Design of Image Quality in Medical X-Ray Film

A quality control programme for medical X-ray films in India

Medical X-ray films are continued to be the major image receptors in diagnostic radiology in India. About 9×10⁶ m² of medical X-ray films are used per annum for diagnostic imaging in India, and its magnitude may further increase as the number of diagnostic X-ray units is increasing rapidly. A national quality control programme was initiated for testing the medical X-ray films of various suppliers/manufacturers so that optimum quality film can only be used in diagnostic radiography examinations. X-ray laboratory of Radiological Physics and Advisory Division, Bhabha Atomic Research Centre was recognised as national film testing laboratory. A dedicated test phantom was fabricated as per the prescription of International Organization for Standardization (ISO 9236-I, 1996), simulating the attenuation and scatter properties of chest of an average patient for periodic X-ray sensitometric evaluations of the medical X-ray films. The basic fog, speed, latitude, maximum optical density, uniformity and artefacts of all the films tested so far were found well within the requirements specified in the national standards. The average gradient for a few blue and green sensitive films were found less than the specified value. Suppliers/manufacturers of such films were advised to improve the performance quality of their films.

Design of Silver Bromoiodide Grains Containing Rich Silver Iodide at Their Inner Site for Monodispersed Silver Halide Emulsion - Utilization of the Emulsion to Medical X-Ray Film -

Design of Silver Bromoiodide Grains Containing Rich Silver Iodide at Their Inner Site for Monodispersed Silver Halide Emulsion - Utilization of the Emulsion to Medical X-Ray Film -

Ataxia Telangiectasia Mutated (ATM)-mediated DNA Damage Response in Oxidative Stress-induced Vascular Endothelial Cell Senescence

Oxidative stress regulates dysfunction and senescence of vascular endothelial cells. The DNA damage response and its main signaling pathway involving ataxia telangiectasia mutated (ATM) have been implicated in playing a central role in mediating the actions of oxidative stress; however, the role of the ATM signaling pathway in vascular pathogenesis has largely remained unclear. Here, we identify ATM to regulate oxidative stress-induced endothelial cell dysfunction and premature senescence. Oxidative stress induced senescence in endothelial cells through activation/phosphorylation of ATM by way of an Akt/p53/p21-mediated pathway. These actions were abrogated in cells in which ATM was knocked down by RNA interference or inhibited by specific inhibitory compounds. Furthermore, the in vivo significance of this regulatory pathway was confirmed using ATM knock-out mice in which induction of senescent endothelial cells in the aorta in a diabetic mouse model of endothelial dysfunction and senescence was attenuated in contrast to pathological changes seen in wild-type mice. Collectively, our results show that ATM through an ATM/Akt/p53/p21-dependent signaling pathway mediates an instructive role in oxidative stress-induced endothelial dysfunction and premature senescence.

O-GlcNAc Protein Modification in Cancer Cells Increases in Response to Glucose Deprivation through Glycogen Degradation

When cellular glucose concentrations fall below normal levels, in general the extent of protein O-GlcNAc modification (O-GlcNAcylation) decreases. However, recent reports demonstrated increased O-GlcNAcylation by glucose deprivation in HepG2 and Neuro-2a cells. Here, we report increased O-GlcNAcylation in non-small cell lung carcinoma A549 cells and various other cells in response to glucose deprivation. Although the level of O-GlcNAc transferase was unchanged, the enzyme contained less O-GlcNAc, and its activity was increased. Moreover, O-GlcNAcase activity was reduced. The studied cells contain glycogen, and we show that its degradation in response to glucose deprivation provides a source for UDP-GlcNAc required for increased O-GlcNAcylation under this condition. This required active glycogen phosphorylase and resulted in increased glutamine:fructose-6-phosphate amidotransferase, the first and rate-limiting enzyme in the hexosamine biosynthetic pathway. Interestingly, glucose deprivation reduced the amount of phosphofructokinase 1, a regulatory glycolytic enzyme, and blocked ATP synthesis. These findings suggest that glycogen is the source for increased O-GlcNAcylation but not for generating ATP in response to glucose deprivation and that this may be useful for cancer cells to survive.

An Asymmetric Model for Na+-translocating Glutaconyl-CoA Decarboxylases

Glutaconyl-CoA decarboxylase (Gcd) couples the biotin-dependent decarboxylation of glutaconyl-CoA with the generation of an electrochemical Na(+) gradient. Sequencing of the genes encoding all subunits of the Clostridium symbiosum decarboxylase membrane complex revealed that it comprises two distinct biotin carrier subunits, GcdC(1) and GcdC(2), which differ in the length of a central alanine- and proline-rich linker domain. Co-crystallization of the decarboxylase subunit GcdA with the substrate glutaconyl-CoA, the product crotonyl-CoA, and the substrate analogue glutaryl-CoA, respectively, resulted in a high resolution model for substrate binding and catalysis revealing remarkable structural changes upon substrate binding. Unlike the GcdA structure from Acidaminococcus fermentans, these data suggest that in intact Gcd complexes, GcdA is associated as a tetramer crisscrossed by a network of solvent-filled tunnels.

X-ray Source with Cold Emitter Fabricated Using ZnO Conductive Whiskers

A new structure for the surface illuminant X-ray source system using a low-cost aluminum-doped zinc oxide (ZnO:Al) whisker cold emitter is proposed and a prototype setup is introduced. The X-ray source was fabricated using a cold cathode that consists of an aggregation of conductive ZnO:Al whiskers. The ZnO:Al whiskers were deposited on an n-type single crystalline wafer of silicon by an atmospheric chemical-vapor-deposition method. The electron emission current from the ZnO:Al whiskers varied with the Al concentration of ZnO. The diode and triode X-ray sources generated X-rays from the tungsten target used as an anode. X-ray images of a leaf and a small sardine were taken on medical X-ray films. Clear X-ray images were obtained.

Nuclearites search with the TLS detector

It is shown that a thermoluminescent sheet stack (TLS) detector, consisting of TL sheets and medical x-ray films, is an effective nuclearite detector. The TLS can be used for searching lighter nuclearites at sea level owing to the fact that the usual relativistic particles cannot make their tracks in the TLS unless they have a charge of larger than 50. We will report recent results of searching for lighter nuclearites at sea level.

Case report: hydroquinone and/or glutaraldehyde induced acute myeloid leukaemia?

BackgroundExposures to high doses of irradiation, to chemotherapy, benzene, petroleum products, paints, embalming fluids, ethylene oxide, herbicides, pesticides, and smoking have been associated with an increased risk of acute myelogenous leukemia (AML). Although there in no epidemiological evidence of relation between X-ray developer, fixer and replenisher liquids and AML, these included glutaraldehyde which has weakly associated with lymphocytic leukemia in rats and hydroquinone has been increasingly implicated in producing leukemia, causing DNA and chromosomal damage, inhibits topo-isomerase II, alter hematopoiesis and inhibit apoptosis of neoplastic cells.Case presentationTwo white females (A and B) hired in 1985 as medical radiation technologists in a primary care center, in Greece. In July 2001, woman A, 38-years-old, was diagnosed as having acute monocytic leukaemia (FAB M5). The patient did not respond to therapy and died threeweeks later. In August 2001, woman B, 35-year-old, was diagnosed with acute promyelocytic leukaemia (FAB M3). Since discharge, she is in continuous complete remission. Both women were non smokers without any medical history. Shortly after these incidents official inspectors and experts inspected workplace, examined equipment, archives of repairs, notes, interviewed and monitored employees. They concluded that shielding was inadequate for balcony's door but personal monitoring did not show any exceeding of TLV of 20 mSv yearly and cytogenetics analysis did not reveal findings considered to be characteristics of ionizing exposure. Equipment for developing photos had a long list of repairs, mainly leakages of liquids and increases of temperature. On several occasions the floor has been flooded especially during 1987–1993 and 1997–2001. Inspection confirmed a complete lack of ventilation and many spoiled medical x-ray films. Employees reported that an "osmic" level was continuously evident and frequently developed symptoms of respiratory irritation and dizziness.ConclusionThe findings support the hypothesis that the specific AML cases might have originated from exposure to chemicals, especially hydroquinone and/or glutaraldehyde. The report also emphasises the crucial role of inspection of facilities and enforcement of compliance with regulations in order to prevent similar incidents.

Search for Nuclearites using TLS Detector at Sea Level

It is shown that a thermoluminescent sheet stack (TLS) detector, consisting of TL sheets and medical x-ray films, is an effective nuclearite detector. The TLS can be used for searching lighter nuclearites at sea level owing to the fact that the usual relativistic particles cannot make their tracks in the TLS unless they have a charge of larger than 50. We will report recent results of searching for lighter nuclearites at sea level.

A comparison of the imaging characteristics of the new Kodak Hyper Speed G film with the current T-MAT G/RA film and the CR 9000 system

Three standard radiation qualities (RQA 3, RQA 5 and RQA 9) and two screens, Kodak Lanex Regular and Insight Skeletal, were used to compare the imaging performance and dose requirements of the new Kodak Hyper Speed G and the current Kodak T-MAT G/RA medical x-ray films. The noise equivalent quanta (NEQ) and detective quantum efficiencies (DQE) of the four screen–film combinations were measured at three gross optical densities and compared with the characteristics for the Kodak CR 9000 system with GP (general purpose) and HR (high resolution) phosphor plates. The new Hyper Speed G film has double the intrinsic sensitivity of the T-MAT G/RA film and a higher contrast in the high optical density range for comparable exposure latitude. By providing both high sensitivity and high spatial resolution, the new film significantly improves the compromise between dose and image quality. As expected, the new film has a higher noise level and a lower signal-to-noise ratio than the standard film, although in the high frequency range this is compensated for by a better resolution, giving better DQE results—especially at high optical density. Both screen–film systems outperform the phosphor plates in terms of MTF and DQE for standard imaging conditions (Regular screen at RQA 5 and RQA 9 beam qualities). At low energy (RQA 3), the CR system has a comparable low-frequency DQE to screen–film systems when used with a fine screen at low and middle optical densities, and a superior low-frequency DQE at high optical density.

Silver recovery from synthetic photographic and medical X-ray process effluents using activated carbon

Adsorption of silver from synthetic photographic and spent fix solutions on granulated activated carbon in a batch process has been investigated. The synthetic solutions prepared had similar properties to medical X-ray and photographic process effluents. Sodium and ammonium thiosulfates are the major lixiviants used in the dissolution of silver halides present in photographic and medical X-ray films. The resultant solutions contain substantial amounts of recoverable silver complexes in the form of thiosulfates. The as received carbons were alkaline in nature when contacted with deionised water. These carbons showed very low silver recoveries. However, when these carbons were pre-treated with 0.5 mol/dm 3 sulphuric and nitric acids at 25 °C, it had resulted in significant silver recoveries of 98.5% and 95% from sodium and ammonium thiosulfate solutions, respectively. These results were achieved in a narrow range of pH between 3 and 4. Batch atmospheric stripping of adsorbed silver by 2.0 mol/dm 3 HNO 3 at 85 °C was also investigated.

Degradation of medical X-ray film developing wastewaters by advanced oxidation processes

Effluents from X-ray film developing processes feature high contaminant load (COD about 200 g/l). Identification of the main organics present in these wastewaters was performed by using liquid chromatography-mass spectrometry in electron impact mode, LC-(EI)MS. Both, unconsumed ingredients and sulphonated/hydroxylated derivatives and dimers yielded from the developing agents hydroquinone and phenidone were found to be the main organics contributing to the contaminant load of these effluents. Their potential degradation by oxidation with both photo- and thermal-Fenton reactions was investigated and the optimal degradation conditions were determined. Under these conditions the initial COD was reduced by about 97% within 6 h of treatment. The intermediates detected by LC-(EI)MS in the oxidation of hydroquinone and phenidone during the treatment were essentially hydroxylated derivatives and dimers and the residual organic matter was mainly made up of carboxylic acids. Reaction pathways for the oxidation of the developing agents hydroquinone and phenidone were proposed. The presence of many organic and inorganic components in the wastewaters did not affected the favoured oxidation route of these developers. The results obtained allow to assess the reduction of costs permitted in the treatment of X-ray effluents with the photo- and thermal-Fenton reaction without affecting the degradation degree and quality of the discharge.

Search for nuclearites using the TL stack detector

It is shown that a thermoluminescent (TL) sheet stack detector,consisting of TL sheets and medical x-ray films, is an effective nuclearitedetector. Nuclearite energy loss is not explicitly used for the estimationof the TL stack sensitivity to nuclearites, but implicitly by consideringways of energy deposition. The 90% confidence levelflux limit obtained with the TL stack detector is givenfor a certain β-M range of nuclearites. Fornuclearites of β = 10-3 at sea level andM⩾2×1015 GeV c-2, the limit is 1.3×10-13 s-1 cm-2 sr-1.