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Yun HH, Choi GW, Kim WT, Yoon JR. Differentiating Nutrient Artery Canals of the Femur versus Fracture Lines in Patients with Total Hip Arthroplasty on Plain Radiographs. Indian J Orthop 2019; 53:622-629. [PMID: 31488931 PMCID: PMC6699210 DOI: 10.4103/ortho.ijortho_171_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Nutrient artery canals of the femur are often visible on plain radiographs as radiolucent lines which may mimic fracture lines. The purpose of this study was to distinguish nutrient artery canals from fracture lines on plain radiographs. MATERIALS AND METHODS Ninety-three patients (102 hips) with an average age of 65.6 years were included in the study. We retrospectively analyzed nutrient artery canals of the femur on pre and postoperative anteroposterior (AP) and cross-table lateral (CTL) hip radiographs in patients with cementless total hip arthroplasty. The shape, number, location, direction of obliquity, length of nutrient artery canal, and the distance between the tip of the greater trochanter and the proximal end of the nutrient artery canal were measured. RESULTS Nutrient artery canals were determined in 54 hips (53.0%) on preoperative radiographs. The numbers of nutrient artery canals were entirely found to be one for each hip. The nutrient artery canals of the femur were the most frequently seen in the cortex on CTL radiographs with 32 hips (31.4%), whereas nutrient artery canals were not seen at all in the cortex on AP radiographs. All nutrient artery canals in the cortex on CTL radiographs coursed upward obliquely. Comparing to fracture lines, nutrient artery canals show less radiolucency, smaller diameter, and blunted ends in both the cortex and medullary cavity, show sclerotic walls in the cortex and have the less straight course in the medullary cavity. CONCLUSIONS Based on the results of this study, there are clearly distinguishable differences between nutrient artery canals of the femur and fracture lines on plain radiographs.
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Affiliation(s)
- Ho Hyun Yun
- Department of Orthopaedic Surgery, Seoul Veterans Hospital, Seoul, South Korea,Address for correspondence: Dr. Ho Hyun Yun, Department of Orthopaedic Surgery, Seoul Veterans Hospital, #6-2 Dunchon-Dong, Gangdong-Gu, 134791 Seoul, South Korea. E-mail:
| | - Gi Won Choi
- Department of Orthopaedic Surgery, Korea University College of Medicine, Ansan Hospital, Gyeonggi-do, South Korea
| | - Wan Tae Kim
- Department of Radiology, Seoul Veterans Hospital, Seoul, South Korea
| | - Jung Ro Yoon
- Department of Orthopaedic Surgery, Seoul Veterans Hospital, Seoul, South Korea
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Baker M. Investigation into Factors Influencing Fuji S-Value Using an Extremity Phantom. J Med Imaging Radiat Sci 2012; 43:34-37. [PMID: 31052017 DOI: 10.1016/j.jmir.2011.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 07/14/2011] [Accepted: 08/11/2011] [Indexed: 10/16/2022]
Abstract
Exposure indices are provided by manufacturers to give an indication of exposure for computed radiography (CR). Although there are recommended ranges for exposure index values for various examinations, they may be affected by a number of other factors in addition to exposure. This study using an extremity phantom found collimation to be the most important factor influencing the S-value for a Fuji CR system. It is therefore essential that collimation is kept as tight as possible without excluding relevant anatomy. CR imaging plates should be processed rapidly after exposure to prevent loss of information stored in the latent image. The reliability of the S-value exposure index as an indicator of exposures can be increased with better understanding of how it works, and by practical application of this knowledge to radiography.
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Affiliation(s)
- Martin Baker
- Department of Veterinary Clinical Sciences, University of Liverpool, Small Animal Teaching Hospital, Neston, Wirral, UK
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Yun HH, Yi JW, Lim DS, Park SC, Oh SR. Reliability of the Radiologic Measurement Methods for Assessment of Osteoporosis Using the Digital Hip Radiograph. ACTA ACUST UNITED AC 2011. [DOI: 10.5371/jkhs.2011.23.2.142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Ho Hyun Yun
- Department of Orthopedic Surgery, Seoul Veterans Hospital, Seoul, Korea
| | - Ju-Won Yi
- Department of Orthopedic Surgery, College of Medicine, Ewha Womans University, Seoul, Korea
| | - Deuk-Soo Lim
- Department of Orthopedic Surgery, Seoul Veterans Hospital, Seoul, Korea
| | - Sung Chul Park
- Department of Orthopedic Surgery, Seoul Veterans Hospital, Seoul, Korea
| | - Seong Rok Oh
- Department of Orthopedic Surgery, Seoul Veterans Hospital, Seoul, Korea
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Hurlen P, Borthne A, Dahl FA, Ostbye T, Gulbrandsen P. Does PACS improve diagnostic accuracy in chest radiograph interpretations in clinical practice? Eur J Radiol 2010; 81:173-7. [PMID: 20888718 DOI: 10.1016/j.ejrad.2010.08.043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Revised: 08/27/2010] [Accepted: 08/30/2010] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To assess the impact of a Picture Archiving and Communication System (PACS) on the diagnostic accuracy of the interpretation of chest radiology examinations in a "real life" radiology setting. MATERIALS AND METHODS During a period before PACS was introduced to radiologists, when images were still interpreted on film and reported on paper, images and reports were also digitally stored in an image database. The same database was used after the PACS introduction. This provided a unique opportunity to conduct a blinded retrospective study, comparing sensitivity (the main outcome parameter) in the pre and post-PACS periods. We selected 56 digitally stored chest radiograph examinations that were originally read and reported on film, and 66 examinations that were read and reported on screen 2 years after the PACS introduction. Each examination was assigned a random number, and both reports and images were scored independently for pathological findings. The blinded retrospective score for the original reports were then compared with the score for the images (the gold standard). RESULTS Sensitivity was improved after the PACS introduction. When both certain and uncertain findings were included, this improvement was statistically significant. There were no other statistically significant changes. CONCLUSION The result is consistent with prospective studies concluding that diagnostic accuracy is at least not reduced after PACS introduction. The sensitivity may even be improved.
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Affiliation(s)
- Petter Hurlen
- Helse Sør-Øst Health Services Research Centre, Akershus University Hospital, Sykehusveien 27, NO-1478 Lørenskog, Norway.
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Vedantham S, Karellas A. Modeling the performance characteristics of computed radiography (CR) systems. IEEE TRANSACTIONS ON MEDICAL IMAGING 2010; 29:790-806. [PMID: 20199915 PMCID: PMC5228607 DOI: 10.1109/tmi.2009.2036995] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Computed radiography (CR) using storage phosphors is widely used in digital radiography and mammography. A cascaded linear systems approach wherein several parameter values were estimated using Monte Carlo methods was used to model the image formation process of a single-side read ;;flying spot'' CR system using a granular phosphor. Objective image quality metrics such as modulation transfer function and detective quantum efficiency were determined using this model and show good agreement with published empirical data. A model such as that addressed in this work could allow for improved understanding of the effect of storage phosphor physical properties and CR reader parameters on objective image quality metrics for existing and evolving CR systems.
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Affiliation(s)
- Srinivasan Vedantham
- Department of Radiology, University of Massachusetts Medical School, Worcester, MA 01655, USA.
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Evaluation of Singh index for assessment of osteoporosis using digital radiography. Eur J Radiol 2009; 71:152-8. [DOI: 10.1016/j.ejrad.2008.03.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 03/05/2008] [Accepted: 03/13/2008] [Indexed: 11/18/2022]
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Hurlen P, Østbye T, Borthne A, Gulbrandsen P. Introducing PACS to the late majority. A longitudinal study. J Digit Imaging 2008; 23:87-94. [PMID: 18979133 DOI: 10.1007/s10278-008-9160-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 08/21/2008] [Accepted: 09/28/2008] [Indexed: 11/30/2022] Open
Abstract
The purpose of this study was to study whether the benefits from introducing a picture archiving and communication systems (PACS) reported by innovators and early adopters also can be achieved by a hospital belonging to the "late majority" and to see whether such benefits are sustained, using report turnaround time (RTAT) as an indicator. Activity-related data was retrieved from the radiology information system (RIS) over a 2-year period. The median RTAT for preliminary reports was initially reduced from 12 to 2 h then increased to 3 h. For final reports, the median RTAT was initially reduced from 23 to 13 h then gradually reverted back to 22 h. Innovators and early adopters demonstrate not only that positive results can be achieved but also the importance of involving key personnel. We believe that such involvement and the focus on wider organizational concerns are important when introducing PACS to the late majority, both for achieving and sustaining positive results.
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Affiliation(s)
- Petter Hurlen
- Helse Sør-Øst Health Services Research Centre, Akershus University Hospital, Mail Drawer 95, NO-1478, Lørenskog, Norway.
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Soh HS, Ung NM, Ng KH. The characteristics of Fuji IP Cassette Type PII and application for radiation oncology quality assurance tests and portal imaging. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2008; 31:146-50. [PMID: 18697706 DOI: 10.1007/bf03178589] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The advancement of digital imaging has prompted more medical institutions to go filmless. The computed radiography (CR) system is becoming an important tool not only in diagnostic imaging, but also in radiation oncology. A new CR system that was specially designed for the use in radiation oncology, Fuji IP cassette type PII has been introduced to the market in the middle of year 2006. This project aimed to study some basic physical characteristics of this new type of cassette and explore its application for performing quality assurance (QA) tests and portal imaging in radiotherapy. All the images were read by FCR 5000 Plus reader. The image was found to reach its saturation value of 1023 (due to the image was stored in 10 bits data) by depending on the sensitivity value being adjusted. The uniformity test gave the result of 0.12%. The cassette was used to perform the QA tests which were previously performed using film. All the results met the specification as stated in AAPM Task Group 40. The comparison for the portal images of PortalVision contrast-detail phantom showed that the spatial resolution of the images obtained by CR system (Fujifilm Co., Ltd., Tokyo, Japan) were better than the EPID (Varian Medical Systems, Inc., Palo Alto, USA) and film system (Eastman Kodak Co., New York, USA). The IP cassette type PII was found to be suitable as an alternative QA test tool and portal imaging in radiotherapy.
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Affiliation(s)
- H S Soh
- Department of Biomedical Imaging, University of Malaya, Kuala Lumpur, Malaysia
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Do clinicians read our reports? Integrating the radiology information system with the electronic patient record: experiences from the first 2 years. Eur Radiol 2008; 19:31-6. [PMID: 18682959 DOI: 10.1007/s00330-008-1098-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Accepted: 06/06/2008] [Indexed: 10/21/2022]
Abstract
This study aimed to determine how clinicians adapted to and utilized new routines for accessing radiology reports after the integration of an electronic patient record (EPR) with a radiology information system (RIS). Activity-related data describing the availability and receipt of radiology reports were collected from the EPR and the RIS over a period of 2 years. Twelve percent of the final radiology reports had not been opened 4 weeks after they had been entered into the EPR. For opened reports, the median time after a report was available in the EPR until it was first opened by a clinician was less than 1 h for preliminary reports and less than 4 h for final radiology reports. The use of radiology reports was stable during the second observation year. Some reports were not opened for professional as well as technical reasons. The integrated information systems offered a potential for improving routines related to the transmission of radiology reports. Clinicians did not fully take advantage of this potential in the 2 years after its introduction.
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Paech A, Schulz AP, Hahlbrauck B, Kiene J, Wenzl ME, Jürgens C. Physical evaluation of a new technique for X-ray dose reduction: Measurement of signal-to-noise ratio and modulation transfer function in an animal model. Phys Med 2007; 23:33-40. [PMID: 17568541 DOI: 10.1016/j.ejmp.2006.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 12/18/2006] [Accepted: 12/27/2006] [Indexed: 12/01/2022] Open
Abstract
Aim of this study was to record objective changes in image quality of optically re-exposed, radiation-reduced X-ray images in comparison to a normally exposed reference image in an animal model. Under investigation is the question if optical re-exposure of conventional, radiation-reduced X-ray images partially or even fully compensates the loss of information caused by underexposure. Dose-reduced, underexposed images were prepared by reducing the mAs product to 50% with constant anode voltage. Reproduction of the image was performed with a 52% decrease in the radiation dose. Comparing different re-exposure times, the optimal time was found to be 60s. These underexposed X-rays were then optically re-exposed for a defined period of time before development. In all X-ray images of the animal model, different osseous structures were defined as regions of interest (ROI) for evaluation of the objective changes in image quality. The density curves were plotted with the two-beamed densitometer. The contrast transfer factors as the function of local frequency were determined from this, which served as the basis for calculating the modulation transfer factor. To establish if X-ray sensitisation by optical re-exposure leads to a change in the sensitometric gradation, the sensitometric curves were determined using a standardized aluminum scale and thermal luminescence dosimetry. In the comparison the lowest correlation with the standard technique film (X-ray 1) was seen in the purely dose-reduced X-ray. In the range of 1.6-3.4Lp/mm, both SNR curves have an identical course. Despite a 52% dose reduction in the re-exposed image, both densitometry curves of the conventional and re-exposed X-ray show an almost identical distribution of the transmittance levels. In conclusion film sensitisation provides a technically simple and inexpensive procedure, which is easily integrated into previous film development processes and considerably reduces the patient radiation exposure as well as clearly improving the image quality.
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Affiliation(s)
- A Paech
- University Hospital Schleswig Holstein, Campus Lübeck, Department of Orthopaedics and Trauma, Ratzeburger Allee 160, 23538 Lübeck, Germany.
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Offiah AC, Moon L, Hall CM, Todd-Pokropek A. Diagnostic accuracy of fracture detection in suspected non-accidental injury: the effect of edge enhancement and digital display on observer performance. Clin Radiol 2006; 61:163-73. [PMID: 16439222 DOI: 10.1016/j.crad.2005.09.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Revised: 09/13/2005] [Accepted: 09/13/2005] [Indexed: 11/17/2022]
Abstract
AIM To compare the effect of varying degrees of edge enhancement and method of digital image display on fracture detection in suspected non-accidental injury (NAI). MATERIALS AND METHODS Fifty radiographs from post-mortem skeletal surveys in 13 children with suspected NAI were selected. Images were obtained using a Fuji 5000R computed radiography system. Hard copies were printed with edge enhancement factors 0, 0.5 and 1.2. Images (edge enhancement 0.5) were also displayed on a 1K(2) monitor. Six observers independently evaluated all 200 images for the presence of abnormality. Observers also scored each image for visualization of soft tissues, visualization of trabecular markings and overall image quality. The paired Student's t-test and location receiver operating curve (ROC) analysis were used to compare quality scores and diagnostic accuracy of each display method. Individual and pooled true-positive rates (sensitivity) were determined. For the purposes of ROC analysis, histology was taken as the gold standard. RESULTS There was no difference in duration of hard and soft-copy reading sessions (p=0.76). After image manipulation soft-copy radiographs scored significantly better for image quality than hard copy (p<0.0001). Pooled observer sensitivity (at a specificity of 90%) was below 50% for all display methods. Diagnostic accuracy varied significantly between observers. Diagnostic accuracy of individual observers was not affected by display method. CONCLUSION In suspected NAI, diagnostic accuracy of fracture detection is generally low. Diagnostic accuracy appears to be affected more by observer-related factors than by the method of digital image display.
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Affiliation(s)
- A C Offiah
- Department of Radiology, Great Ormond Street Hospital for Children, London, UK.
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Offiah AC, Grehan J, Hall CM, Todd-Pokropek A. Optimal exposure parameters for digital radiography of the infant skull: A pilot study. Clin Radiol 2005; 60:1195-204. [PMID: 16223616 DOI: 10.1016/j.crad.2005.06.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2004] [Revised: 05/11/2005] [Accepted: 06/27/2005] [Indexed: 11/17/2022]
Abstract
AIM To determine optimal exposure parameters when performing digital skull radiographs in infants with suspected non-accidental injury (NAI). METHOD Anteroposterior and lateral post-mortem skull radiographs of six consecutive infants with suspected NAI were made at six exposure levels for each projection. Entrance surface doses ranged from 75-351 microGy. Exposures were made with a Fuji 5000R computed radiography system onto a standard resolution imaging plate. In three patients exposures were repeated using a high-resolution imaging plate. Hard copy images with an edge-enhancement factor of 0.5 were produced. Six observers assessed and scored the radiographs from 1=poor to 5=excellent for visualization of five criteria. The criteria scored included outer table of skull vault, inner table of skull vault, suture margins, vascular markings and soft tissues of the scalp. Radiographs were then ranked in order of overall image quality. Film density and sensitivity values were recorded. Local research committee approval was obtained. RESULTS Current parameters give an average entrance surface dose of 253 microGy and 246 microGy for anteroposterior and lateral radiographs, respectively. The study demonstrated no perceived improvement in image quality above an entrance surface dose of 200 microGy (80% of current dose) or by the use of a high-resolution imaging plate. CONCLUSION The potential exists to reduce radiation exposure in infants. A study has commenced to determine the effects of dose reduction on diagnostic accuracy in suspected NAI.
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Affiliation(s)
- A C Offiah
- Department of Radiology, Great Ormond Street Hospital for Children, London, UK
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Monnin P, Gutierrez D, Bulling S, Lepori D, Verdun FR. 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. Phys Med Biol 2005; 50:4541-52. [PMID: 16177488 DOI: 10.1088/0031-9155/50/19/008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
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.
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Affiliation(s)
- P Monnin
- Institut universitaire de Radiophysique Appliquée (IRA), CH-1007 Lausanne, Switzerland
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Lindhardt F. Organisational changes made possible with Viborg PACS. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2001; 66:37-40. [PMID: 11378220 DOI: 10.1016/s0169-2607(01)00132-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Organisational changes take place at three different levels: at the department, in the hospital and in the county. Important changes locally are the easy and fast access to better images, a rise in production and a possible reduction in patient stay. The radiological services to the community improve, reading can be done anytime and anywhere and a specialist is always available because of PACS and networks. One doctor can be on-call for the whole county.
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Affiliation(s)
- F Lindhardt
- Department of Diagnostic Imaging, Viborg Hospital, 4, Heibergs Allé, 8800, Viborg, Denmark
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Bradford CD, Peppler WW, Dobbins JT. Performance characteristics of a Kodak computed radiography system. Med Phys 1999; 26:27-37. [PMID: 9949395 DOI: 10.1118/1.598781] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The performance characteristics of a photostimulable phosphor based computed radiographic (CR) system were studied. The modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE) of the Kodak Digital Science computed radiography (CR) system (Eastman Kodak Co.-model 400) were measured and compared to previously published results of a Fuji based CR system (Philips Medical Systems-PCR model 7000). To maximize comparability, the same measurement techniques and analysis methods were used. The DQE at four exposure levels (30, 3, 0.3, 0.03 mR) and two plate types (standard and high resolution) were calculated from the NPS and MTF measurements. The NPS was determined from two-dimensional Fourier analysis of uniformly exposed plates. The presampling MTF was determined from the Fourier transform (FT) of the system's finely sampled line spread function (LSF) as produced by a narrow slit. A comparison of the slit type ("beveled edge" versus "straight edge") and its effect on the resulting MTF measurements was also performed. The results show that both systems are comparable in resolution performance. The noise power studies indicated a higher level of noise for the Kodak images (approximately 20% at the low exposure levels and 40%-70% at higher exposure levels). Within the clinically relevant exposure range (0.3-3 mR), the resulting DQE for the Kodak plates ranged between 20%-50% lower than for the corresponding Fuji plates. Measurements of the presampling MTF with the two slit types have shown that a correction factor can be applied to compensate for transmission through the relief edges.
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Affiliation(s)
- C D Bradford
- Department of Medical Physics, University of Wisconsin, Madison 53706, USA
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Uchida K, Watanabe H, Aoki T, Nakamura K, Nakata H. Clinical evaluation of irreversible data compression for computed radiography of the hand. J Digit Imaging 1998; 11:121-5. [PMID: 9718502 PMCID: PMC3453201 DOI: 10.1007/bf03168735] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We evaluated the clinical utility of high data compression for computed radiography (CR) of the hand. Paired original and compressed CR images were obtained using an FCR 9000 system in 35 patients with various abnormalities of the hand. For the paired original and compressed images, we compared the depiction of the bone cortex, bone trabeculae, soft-tissue, and the margin of the abnormalities. The overall impressions for detectability of the abnormalities and for diagnostic capability were also evaluated. Poorer image quality of the compressed images was noted for most of the structures, but there was no significant difference between the original and compressed images as for the overall impressions for detectability of the abnormalities or for diagnostic capability. We conclude that a high data compression may be clinically acceptable with caution in radiography of the hand.
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Affiliation(s)
- K Uchida
- Department of Radiology, University of Occupational and Environmental Health, Yahatanishi-ku, Japan
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