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Ghazali L, Mohd Yusof MYP, Norman NH. Effects of scanning parameters reduction in dental radiographs on image quality and diagnostic performance: A randomised controlled trial. J Orthod 2020; 48:5-12. [PMID: 33200660 DOI: 10.1177/1465312520971641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVES To investigate the effect of reducing scanning parameters of digital dental panoramic tomogram (DPT) and lateral cephalometric (LC) radiographs on quality and diagnostic performance of the images. DESIGN Single-centre prospective two-arm parallel randomised controlled trial. SETTING Orthodontic Clinic, Faculty of Dentistry, Universiti Teknologi MARA, Selangor, Malaysia. PARTICIPANTS Adult orthodontic patients aged 18-35 years, indicated for DPT and LC, who were fit and healthy with a body mass index of 18.5-25.0, not contraindicated to radiographic examination, not pregnant, and did not have a history of facial or skeletal abnormalities or bone diseases were included. METHODS Thirty-eight adult orthodontic patients were randomised into control and intervention groups. DPT and LC radiographs in the control group were obtained using standard scanning parameters as prescribed by the manufacturer using Orthopantomograph® OP300 by Instrumentarium. Scanning parameters in the intervention group were reduced by 60% for DPT (60 kV, 3.2 mA) and 30% for LC (85 kV, 8 mA). A five-point rating scale was used for the assessment of image quality. Images were evaluated for diagnostic performance by detection of anatomical landmarks. Mann-Whitney test was performed to compare the quality and diagnostic performance of the images and the observer agreement was assessed using the intraclass correlation coefficient (ICC). RESULTS For image quality, the control group produced slightly lower median scores (DPT 2.0, LC 2.0) compared to the intervention group (DPT 2.0, LC 3.0). For diagnostic performance, both groups showed similar median scores (DPT 21.0, LC 32.0). The differences between control and intervention groups for both modalities were not statistically significant. The average scores for intra-observer agreement were excellent (ICC 0.917) and inter-observer agreement was good (ICC 0.822). CONCLUSION Minimising radiation exposure by reducing scanning parameters on digital DPT by 60% and LC by 30% on Intsrumentarium 300 OP did not affect the quality and diagnostic performance of the images. Thus, scanning parameters on digital DPT and LC should be reduced when taking radiographs.
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Affiliation(s)
- Liyana Ghazali
- Centre for Paediatric Dentistry and Orthodontic Studies, Faculty of Dentistry, Universiti Teknologi MARA, Sungai Buloh, Selangor, Malaysia
| | - Mohd Yusmiaidil Putera Mohd Yusof
- Centre for Oral and Maxillofacial Diagnostics and Medicine Studies, Faculty of Dentistry, Universiti Teknologi MARA, Sungai Buloh, Selangor, Malaysia
| | - Noraina Hafizan Norman
- Centre for Paediatric Dentistry and Orthodontic Studies, Faculty of Dentistry, Universiti Teknologi MARA, Sungai Buloh, Selangor, Malaysia
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Abstract
Due to the coronavirus pandemic, all routine dental care in the UK ceased on 25 March 2020. Liverpool University Dental Hospital (LUDH) responded by commencing an emergency dental service on the same date. Clinicians were redeployed within the Hospital to meet the needs of the service, including staffing of the radiology department. LUDH followed Royal College recommendations by taking extraoral radiographs in preference to intraoral radiographs due to the risk of inducing an aerosol. Issues were identified with clinical diagnosis from sectional panoramic radiographs, which led to the introduction of extraoral bitewings being taken as an alternative. A quality assurance audit found that these images provided a substantially lower radiation dose and produced excellent quality images with improved diagnostic accuracy. This article aims to summarise how our radiography practices changed in response to the coronavirus and how the lessons that we have learnt provide an opportunity to modify and improve future practice, beyond the pandemic.
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Affiliation(s)
- Rachel Little
- Orthodontic Department, Liverpool University Dental Hospital, Pembroke Place, Liverpool, Merseyside, L3 5PS, UK.
| | - Jessica Howell
- Orthodontic Department, Liverpool University Dental Hospital, Pembroke Place, Liverpool, Merseyside, L3 5PS, UK
| | - Paul Nixon
- Radiology Department, Liverpool University Dental Hospital, Pembroke Place, Liverpool, Merseyside, L3 5PS, UK
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Svenson B, Båth M, Karlsson R, Persson B. A comparison of perceived diagnostic image quality in direct digital panoramic images between standard and advanced external GOP image processing. Acta Odontol Scand 2019; 77:560-565. [PMID: 31146623 DOI: 10.1080/00016357.2019.1618912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Objective: The objective of the present study was to study the effect of adaptive image processing (GOP processing) on the visibility of anatomical structures in direct digital panoramic images. Material and methods: The study comprised panoramic images of 50 consecutive adult individuals aged 18-60 years. Nine dentists working with dental radiology compared the structural image quality of all standard-processed and GOP-processed panoramic images for six anatomical structures, using a six-point scale for visual grading characteristics analysis. Results: For all anatomic structures a statistically significant difference in favour of the GOP was found. Conclusions: The present study shows that it is possible to improve perceived diagnostic image quality of direct digital panoramic radiography using GOP technology compared to the manufacturers' standard processing. Manufacturers' image-processing programs can be further developed, as there is a possibility of improving the perceived diagnostic content of an image with external processing.
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Affiliation(s)
- Björn Svenson
- Department of Dental Research, Postgraduate Dental Education Center, Örebro, Sweden
- School of Health and Medical Sciences, Örebro University, Örebro, Sweden
| | - Magnus Båth
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
- Department of Radiation Physics, Institute of Clinical Sciences at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Reet Karlsson
- Department of Radiology, Skaraborg Hospital Skövde, Skövde, Sweden
| | - Bo Persson
- Department of Radiology, Skaraborg Hospital Skövde, Skövde, Sweden
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Svenson B, Båth M, Karlsson R. Can adaptive post-processing of storage phosphor plate panoramic radiographs provide better image quality? A comparison of anatomical image quality of panoramic radiographs before and after adaptive processing. Acta Odontol Scand 2019; 77:328-333. [PMID: 30623704 DOI: 10.1080/00016357.2018.1556801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The objective of the present study was to study the effect of adaptive image processing on the visibility of anatomical structures in storage phosphor plate (SPP) panoramic images. MATERIALS AND METHODS Three hundred SPP panoramic X-ray radiographs of children and adolescents were used. The radiographs were post-processed using general operator processor (GOP) technology, resulting in both a standard-processed and a GOP-processed radiograph. Four specialists in dental radiology compared the structural image quality of all standard-processed and GOP-processed panorama images for six anatomical structures, using a six-point scale for visual grading characteristics (VGC) analysis. RESULTS For three of the anatomic structures - the root canal space of the mandibular left first premolar, mandibular canal left side and periodontal ligament space of the mandibular right first molar - there was a statistically significant difference to the GOP's advantage. For the three remaining structures - dentino-enamel junction of the maxillary right first molar, crista alveolaris of the mandibular left molar area and floor of maxillary sinus right side - no significant difference between standard processing and GOP processing was obtained. CONCLUSIONS The study demonstrates that it is possible to improve the quality of SPP radiographs and the visibility of anatomical structures by using the GOP technique. Manufacturers' image-processing programs can be further developed, as there is a possibility of improving the diagnostic content of an image with external processing.
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Affiliation(s)
- Björn Svenson
- Dental Research Department, Postgraduate Dental Education Center, Örebro, Sweden
- School of Health and Medical Sciences, Örebro University, Örebro, Sweden
| | - Magnus Båth
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
- Department of Radiation Physics, Institute of Clinical Sciences at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Reet Karlsson
- Department of Radiology, Skaraborg Hospital, Skövde, Sweden
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Weerawanich W, Shimizu M, Takeshita Y, Okamura K, Yoshida S, Jasa GR, Yoshiura K. Determination of optimum exposure parameters for dentoalveolar structures of the jaws using the CB MercuRay system with cluster signal-to-noise analysis. Oral Radiol 2018; 35:260-271. [PMID: 30484205 DOI: 10.1007/s11282-018-0348-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/23/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE To determine the optimum cone beam computed tomography exposure parameters for specific diagnostic tasks. METHODS A Teflon phantom attached to a half-mandible in a large container was scanned in dental (D), implant (I), and panoramic (P) modes. An identical phantom in a small container was scanned in D mode. Both were scanned at 60, 80, 100, and 120 kV. We evaluated the image quality of five anatomical structures [dentinoenamel junction (1), lamina dura and periodontal ligament space (2), trabecular pattern (3), cortex-spongy bone junction (4), and pulp chamber and root canal (5)] and analyzed the diagnostic image quality with cluster signal-to-noise analysis. We then evaluated correlations between the two image qualities and calculated the threshold of acceptable diagnostic image quality. Optimum exposure parameters were determined from images with acceptable diagnostic image quality. RESULTS For the small container, the optimum exposure parameters were D mode, 80 kV for (1), (3), and (4) and D mode, 100 kV for (5). For the large container, they were D mode, 120 kV for (1), (3), and (5) and D mode, 100 kV for (4). I mode, 120 kV reached the acceptable level for (4). No images reached the acceptable level for (2). CONCLUSIONS No optimum exposure parameters were identified for the evaluation of the lamina dura and periodontal ligament space. D mode was sufficient for the other structures; however, the tube voltage required for each structure differed. Smaller patients required lower tube voltage. I mode, 120 kV may be used for larger lesions.
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Affiliation(s)
- Warangkana Weerawanich
- Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan. .,Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Mahidol University, 6 Yothi Road, Ratchathewi, Bangkok, 10400, Thailand.
| | - Mayumi Shimizu
- Department of Oral and Maxillofacial Radiology, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Yohei Takeshita
- Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8558, Japan
| | - Kazutoshi Okamura
- Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Shoko Yoshida
- Section of Image Diagnostics, Department of Diagnostics and General Care, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka, 814-0193, Japan
| | - Gainer R Jasa
- Oral Radiology Division, Faculty of Odontology, University of the Republic, Las Heras 1925, 11600, Montevideo, Uruguay
| | - Kazunori Yoshiura
- Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
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Kallio-Pulkkinen S, Haapea M, Liukkonen E, Huumonen S, Tervonen O, Nieminen MT. Comparison between DICOM-calibrated and uncalibrated consumer grade and 6-MP displays under different lighting conditions in panoramic radiography. Dentomaxillofac Radiol 2015; 44:20140365. [PMID: 25564888 DOI: 10.1259/dmfr.20140365] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES To compare observer performance in the detection of anatomical structures and pathology in panoramic radiographs using consumer grade with and without digital imaging and communication in medicine (DICOM)-calibration and 6-megapixel (6-MP) displays under different lighting conditions. METHODS 30 panoramic radiographs were randomly evaluated on three displays under bright (510 lx) and dim (16 lx) ambient lighting by two observers with different years of experience. Dentinoenamel junction, dentinal caries and periapical inflammatory lesions, visibility of cortical border of the floor and pathological lesions in maxillary sinus were evaluated. Consensus between the observers was considered as reference. Intraobserver agreement was determined. Proportion of equivalent ratings and weighted kappa were used to assess reliability. The level of significance was set to p < 0.05. RESULTS The proportion of equivalent ratings with consensus differed between uncalibrated and DICOM-calibrated consumer grade displays in dentinal caries in the lower molar in dim lighting (p = 0.021) and between DICOM-calibrated consumer grade and 6-MP display in bright lighting (p = 0.038) for an experienced observer. Significant differences were found between uncalibrated and DICOM-calibrated consumer grade displays in dentinal caries in bright lighting (p = 0.044) and periapical lesions in the upper molar in dim lighting (p = 0.008) for a less experienced observer. Intraobserver reliability was better at detecting dentinal caries than at detecting periapical and maxillary sinus pathology. CONCLUSIONS DICOM calibration may improve observer performance in panoramic radiography in different lighting conditions. Therefore, a DICOM-calibrated consumer grade display can be used instead of a medical display in dental practice without compromising the diagnostic quality.
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Affiliation(s)
- S Kallio-Pulkkinen
- 1 Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland
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Kallio-Pulkkinen S, Haapea M, Liukkonen E, Huumonen S, Tervonen O, Nieminen MT. Comparison of consumer grade, tablet and 6MP-displays: observer performance in detection of anatomical and pathological structures in panoramic radiographs. Oral Surg Oral Med Oral Pathol Oral Radiol 2014; 118:135-41. [DOI: 10.1016/j.oooo.2014.04.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 03/21/2014] [Accepted: 04/08/2014] [Indexed: 11/29/2022]
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Sabarudin A, Tiau YJ. Image quality assessment in panoramic dental radiography: a comparative study between conventional and digital systems. Quant Imaging Med Surg 2013; 3:43-8. [PMID: 23483085 DOI: 10.3978/j.issn.2223-4292.2013.02.07] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Accepted: 02/23/2013] [Indexed: 11/14/2022]
Abstract
This study is designed to compare and evaluate the diagnostic image quality of dental panoramic radiography between conventional and digital systems. Fifty-four panoramic images were collected and divided into three groups consisting of conventional, digital with and without post processing image. Each image was printed out and scored subjectively by two experienced dentists who were blinded to the exposure parameters and system protocols. The evaluation covers of anatomical coverage and structures, density and image contrast. The overall image quality score revealed that digital panoramic with post-processing scored the highest of 3.45±0.19, followed by digital panoramic system without post-processing and conventional panoramic system with corresponding scores of 3.33±0.33 and 2.06±0.40. In conclusion, images produced by digital panoramic system are better in diagnostic image quality than that from conventional panoramic system. Digital post-processing visualization can improve diagnostic quality significantly in terms of radiographic density and contrast.
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Affiliation(s)
- Akmal Sabarudin
- Diagnostic Imaging & Radiotherapy Program, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 50300, Kuala Lumpur, Malaysia
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Baksi BG, Alpöz E, Sogur E, Mert A. Perception of anatomical structures in digitally filtered and conventional panoramic radiographs: a clinical evaluation. Dentomaxillofac Radiol 2010; 39:424-30. [PMID: 20841460 DOI: 10.1259/dmfr/30570374] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES The aims of the study were to compare subjective image quality of clinical images obtained with a storage phosphor plate (SPP)-based digital and conventional film-based panoramic system for the visualization of various anatomical structures and to evaluate the effect of various processing algorithms on image interpretation. METHODS Panoramic radiographs were taken in 42 patients both with film and with a SPP system. SPP images were treated with shadow, sharpen, negative, greyscale sigma and greyscale exponential filters. Four observers subjectively evaluated films and unfiltered and filtered SPP images for the visibility of anatomical structures with various radiodensities as well as for overall image quality on a three-point rating scale. The statistical methods used were Kruskal-Wallis, odds ratio analysis and Cohen's kappa. RESULTS No statistically significant difference was found between film and unfiltered digital images except for low-contrast structures (P > 0.05). Film images were preferred for the visibility of low-contrast structures (P < 0.05). Best overall image quality was obtained with sharpened images (P < 0.05) followed by films and unfiltered digital images. Among all filtered images, sharpened ones received the highest ratings for the visibility of all anatomical structures (P < 0.05). The intra- and interobserver agreement ranged between moderate and substantial and between fair and moderate, respectively. CONCLUSIONS Film and unfiltered SPP-based panoramic images performed equally well in terms of overall quality; however, films were best for the perception of low-contrast structures. The sharpening filter may be recommended for enhancing SPP panoramic images to improve the visual perception of most of the anatomical structures as well as overall quality.
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Affiliation(s)
- B G Baksi
- Department of Oral Diagnosis & Radiology, School of Dentistry, Ege University, Turkey
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Künzel A, Weimar S, Willers R, Becker J. Diagnostic of tooth fractures with the Vistascan system. Dent Traumatol 2008; 24:537-41. [DOI: 10.1111/j.1600-9657.2008.00638.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Effective dosages for recording Veraviewepocs dental panoramic images: analog film, digital, and panoramic scout for CBCT. ACTA ACUST UNITED AC 2008; 106:571-7. [PMID: 18602314 DOI: 10.1016/j.tripleo.2008.03.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 02/12/2008] [Accepted: 03/28/2008] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the effective doses from analog film, panoramic digital, and panoramic scout for cone-beam computerized tomography (CT). STUDY DESIGN Three different types of Veraviewepocs machines were investigated: Veraviewepocs Conventional, Veraviewepocs Digital, and Veraviewepocs 3D (Morita, Kyoto, Japan). Organ absorbed doses were measured using an anthropomorphic phantom loaded with thermoluminescent dosimeters (TLD 100H) at 16 sites located in sensitive organs. The resulting effective organ doses (muSv) were compared by descriptive statistics. RESULTS The highest value (5.2 muSv) was for Veraviewepocs Conventional. The Veraviewepocs Digital (2.7 muSv) and Veraviewepocs 3D (2.95 muSv) presented low effective doses in the same range. CONCLUSIONS The panoramic digital system delivered the least radiation dose. The use of the panoramic scout for cone-beam CT was marginally higher in dose than its 2D counterpart.
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Kaeppler G, Dietz K, Reinert S. Diagnostic accuracy ofin vitropanoramic radiographs depending on the exposure. Dentomaxillofac Radiol 2007; 36:68-74. [PMID: 17403882 DOI: 10.1259/dmfr/53852973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES The aim was to evaluate the effect of dose reduction on diagnostic accuracy in panoramic radiographs with increased tube potential and reduced milliampere settings. METHODS Panoramic radiographs of 12 dried human skulls prepared with lesions in the bone, teeth and peri-implant bone in ascending size were taken. Medium and regular film--screen combinations and a storage phosphor system were used for imaging. All systems were exposed at a low and a high tube potential level. To compare the dose at different tube potential settings, dose length product was measured at the secondary collimator. Five observers assessed the presence (response: 1) or absence (response: 0) of lesions. Sensitivity, specificity and diagnostic accuracy were evaluated and 36 000 ratings were made in all. All settings were repeated once. Intrarater agreement was expressed by Cohen's kappa coefficient. RESULTS There was no significant difference in diagnostic accuracy between a medium and a regular film--screen combination at a low tube potential level (70 kV; 0.935 and 0.930) and the medium film--screen system at a high tube potential level (85 kV; 0.926). Compared with this group, the regular film-screen combinations at high tube potential level (85 kV, 0.906) and all digital radiographs were significantly different (0.886 and 0.866), irrespective of the tube potential level. The digital panoramic radiograph was only comparable with the best film--screen combinations with an exposure for a medium film-screen system and at a low tube potential level. Sensitivity was 89.9% and specificity 93.7%. The kappa coefficient for intrarater agreement was high (0.81). CONCLUSIONS The medium intensifying screen can be used at high tube potential settings instead of low tube potential settings, or the regular intensifying screen can be used at low tube potential settings with the same diagnostic value. A dose reduction of about 40% is possible. The storage phosphor plates should be exposed at least like a regular film-screen system and at a low tube potential level.
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Affiliation(s)
- G Kaeppler
- Department of Oral Radiology, School of Dental Medicine, University of Tübingen, Tübingen, Germany.
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Kaeppler G, Dietz K, Reinert S. Possibilities of dose reduction in lateral cephalometric radiographs and its effects on clinical diagnostics. Dentomaxillofac Radiol 2007; 36:39-44. [PMID: 17329587 DOI: 10.1259/dmfr/15761373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES The aim of the present study was to determine (1) the absorbed and the exit radiation doses for cephalometric exposures on a phantom head with various exposure settings and image receivers, and (2) the diagnostic image quality for various modalities assessed on cephalometric radiographs of patients. METHODS The dose measurements for lateral cephalometric radiographs were performed with a semiconductor detector, and also with thermoluminescent detectors and an Alderson phantom. Both the integral and the effective doses were determined. Two radiographs of each patient (n=119) were taken at two different times, one at a low tube potential setting, 75+/-5 kV, and one with a decreased dose. Film-screen systems with speed class 400 and one storage phosphor plate were used. Five observers assessed the radiographs for the visualization of six cephalometric reference points on a three-point scale with -1, 0 and 1. Twenty-seven image pairs were rescored to determine inter- and intrarater reliability. The statistical analysis was done using analysis of variance and Tukey's HSD (honestly significant difference) post hoc test. RESULTS Increasing the tube potential setting led to an average dose reduction to 83% (integral dose) or to 87% (effective dose). Instead of taking the radiograph at a low tube potential setting (75 kV), a dose reduction of about 15% was feasible at a high tube potential setting (90 kV). A significant difference in reference point visibility existed between film radiographs at low tube potential settings (mean score 0.984) and at high tube potential settings (90 kV, mean score 0.958). For the storage phosphor plates, there was no significant difference to the film-screen combinations at low tube potential and halved milliampere seconds settings. In the second assessment, there was a high degree of agreement (96.6%) compared with the first assessment (unadjusted for random agreement). CONCLUSIONS As there is only minimal dose reduction at increased tube potential settings, for a dose reduction, it seems to be more useful to use storage phosphor plates at unchanged tube potential and halved milliampere seconds settings compared with the film-screen combination.
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Affiliation(s)
- G Kaeppler
- Zentraler Röntgenbereich, Zentrum für ZMK, Osianderstrasse 2-8, Universität Tübingen, D-72076 Tübingen, Germany.
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