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Katlapa A, Kaartinen SM, Henrik Koivisto J, Matikka H. Radiation exposure to fetus from extremity CBCT examinations. Eur J Radiol 2022; 156:110548. [PMID: 36209537 DOI: 10.1016/j.ejrad.2022.110548] [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: 05/16/2022] [Revised: 09/12/2022] [Accepted: 09/26/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE To evaluate fetal doses from extremity CBCT examinations at different stages of pregnancy and to investigate different methods of fetal dose optimization. METHOD Fetal doses were measured in an anthropomorphic phantom for two CBCT examination protocols - knee and elbow. The measurements were made at three different heights representing the three trimesters during pregnancy and three different depths in the phantom. The effect of soft tissue layer, tube voltage, add-on device shield and body angulation on fetal dose were investigated. RESULTS The fetal doses in clinical examination protocols were in the range of 3.4 to 6.0 µGy during knee examinations and 2.9 to 7.7 µGy during elbow examinations depending on the depth of the fetus and the stage of pregnancy. A soft tissue layer representing variative body composition above abdomen region decreased the fetal dose up to 19 % in knee and up to 21 % in elbow examinations. Using lower tube voltage decreased the fetal doses up to 45 % (knee) and 51 % (elbow). An add-on device shield decreased the fetal doses up to 91 % (knee) and up to 75 % (elbow). Turning the body away from the device bore reduced the fetal doses up to 62 %. The conversion factor to convert an entrance surface dose to the fetal dose ranged from 0.4 to 0.6. CONCLUSIONS The fetal doses from CBCT examinations of extremities are low and do not produce a concern about radiation detriment to the fetus. The most efficient way found to reduce the fetal dose was to use the add-on device shielding.
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Affiliation(s)
- Agnese Katlapa
- Department of Applied Physics, University of Eastern Finland, Yliopistanranta 1 F, 70210, Kuopio, Finland.
| | - Siru M Kaartinen
- Department of Clinical Radiology Kuopio University Hospital Puijonlaaksontie 2, 70210 Kuopio, Finland
| | - Juha Henrik Koivisto
- Department of Physics University of Helsinki, Gustaf Hällströmin katu 2, 00560 Helsinki, Finland
| | - Hanna Matikka
- Department of Clinical Radiology Kuopio University Hospital, Puijonlaaksontie 2, 70210 Kuopio, Finland
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Elameer M, Harris MV, Cox J. Diagnosis of venous thromboembolism in pregnancy: a review of current guidelines. Clin Radiol 2022; 77:904-912. [PMID: 36123200 DOI: 10.1016/j.crad.2022.08.122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 06/25/2022] [Accepted: 08/03/2022] [Indexed: 11/20/2022]
Abstract
Venous thromboembolic disease (VTE) is the leading cause of maternal death throughout the developed world. International and national guidance for the diagnosis and management of VTE in pregnancy is varied and limited, which can result in problems in clinical practice. The imaging challenges of VTE in the general population are challenging but become more complex in pregnancy due to the physiological changes in the circulatory system, which alter clinical judgment and test performance. As an additional factor, the relative radiation risks to the mother and fetus arising from diagnostic tests need to be assessed and communicated to the patient in a clear and understandable way. The purpose of this review is fourfold. We propose to review and summarise the current imaging guidelines available for this condition; critically review the evidence base within the current literature; address the issues of test performance of imaging examinations used for VTE in pregnancy; and address the question of radiation risk and how to communicate this information to patients.
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Affiliation(s)
- M Elameer
- Department of Neuroradiology, Royal Victoria Infirmary, Queen Victoria Road, Newcastle-upon-Tyne NE1 4LP, UK
| | - M V Harris
- Department of Radiology, Sunderland Royal Hospital, Kayll Road, Sunderland, SR4 7TP, UK
| | - J Cox
- Department of Radiology, Sunderland Royal Hospital, Kayll Road, Sunderland, SR4 7TP, UK.
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3
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Matsunaga Y, Haba T, Kobayashi M, Suzuki S, Asada Y, Chida K. Novel pregnant model phantoms for measurement of foetal radiation dose in x-ray examinations. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2021; 41:N12-N21. [PMID: 34233314 DOI: 10.1088/1361-6498/ac125c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
This study presents a comparison of novel pregnant model phantoms with a handmade phantom in terms of shape and radiation measurement points to determine which model is more suitable for measuring the foetal radiation dose during x-ray examinations. Novel pregnant model phantoms were constructed using an anthropomorphic phantom in combination with two differently-sized custom-made abdomen phantoms simulating pregnancy, which were constructed from a polyurethane resin. The size and shape of the polyurethane resin were designed based on abdominal sizes and shapes collected from the computed tomography examinations at 18 pregnant patients of one hospital. The handmade pregnant model phantom was constructed using an anthropomorphic phantom and a beach ball containing water. Compared with the handmade phantom, there were additional dose measurement points on the novel pregnant model phantoms. Our model phantoms improved upon the handmade phantom in terms of shape and radiation measurement points. We produced pregnant model phantoms that simulated the shapes and sizes of actual patients for the first time.
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Affiliation(s)
- Yuta Matsunaga
- Department of Imaging, Nagoya Kyoritsu Hospital, 1-172, Hokke, Nakagawa-ku, Nagoya, Aichi, Japan
- Department of Radiological Technology, Faculty of Health Sciences, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, Japan
| | - Tomonobu Haba
- Faculty of Radiological Technology, School of Health Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, Japan
| | - Masanao Kobayashi
- Faculty of Radiological Technology, School of Health Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, Japan
| | - Shoichi Suzuki
- Faculty of Radiological Technology, School of Health Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, Japan
| | - Yasuki Asada
- Faculty of Radiological Technology, School of Health Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, Japan
| | - Koichi Chida
- Department of Radiological Technology, Faculty of Health Sciences, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, Japan
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Matsunaga Y, Haba T, Kobayashi M, Suzuki S, Asada Y, Chida K. Fetal radiation dose of four tube voltages in abdominal CT examinations during pregnancy: A phantom study. J Appl Clin Med Phys 2021; 22:178-184. [PMID: 33449434 PMCID: PMC7882097 DOI: 10.1002/acm2.13171] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/29/2020] [Accepted: 12/17/2020] [Indexed: 11/05/2022] Open
Abstract
This study aimed to compare the dose and noise level of four tube voltages in abdominal computerized tomography (CT) examinations in different abdominal circumference sizes of pregnant women. Fetal radiation doses were measured with two anthropomorphic pregnant phantoms and real-time dosimeters of photoluminescence sensors using four tube voltages for abdominal CT. The noise level was measured at the abdomen of two anthropomorphic pregnant phantoms. In the large pregnant phantom, the mean fetal doses performed using 120 and 135 kV were statistically significantly lower than the lower tube voltages (P < 0.05). In the small pregnant phantom, the mean fetal dose performed by 100, 120, and 135 kV was significantly lower than the lowest tube voltage tested (P < 0.05). The ratios of the peripheral mean dose to the centric mean dose showed that the ratios of 80 kV were the highest and those for 135 kV were the lowest in both pregnant phantoms. The ratios of the peripheral mean dose to the centric mean dose decreased as the tube voltage increased. Compared with low tube voltages, high tube voltages such as 120 and 135 kV could reduce radiation doses to the fetus without compromising the image uniformity in abdominal CT examinations during pregnancy. On low tube voltage protocols, the dose near the maternal skin surface may be increased in large pregnant women because of reduced penetration of the x rays.
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Affiliation(s)
- Yuta Matsunaga
- Department of ImagingNagoya Kyoritsu HospitalNagoyaAichiJapan
- Department of Radiological TechnologyFaculty of Health SciencesTohoku University Graduate School of MedicineSendaiMiyagiJapan
| | - Tomonobu Haba
- School of Health SciencesFujita Health UniversityToyoakeAichiJapan
| | | | - Shoichi Suzuki
- School of Health SciencesFujita Health UniversityToyoakeAichiJapan
| | - Yasuki Asada
- School of Health SciencesFujita Health UniversityToyoakeAichiJapan
| | - Koichi Chida
- Department of Radiological TechnologyFaculty of Health SciencesTohoku University Graduate School of MedicineSendaiMiyagiJapan
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Tse GH, Balian V, Charalampatou P, Maliakal P, Nayak S, Dyde R, Nagaraja S. Foetal radiation exposure caused by mechanical thrombectomy in large-vessel ischaemic stroke in pregnancy. Neuroradiology 2019; 61:443-449. [PMID: 30770963 DOI: 10.1007/s00234-019-02163-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 01/09/2019] [Indexed: 12/13/2022]
Abstract
PURPOSE There is overwhelming evidence for the clinical benefits that are derived following mechanical thrombectomy in large-vessel acute ischaemic stroke. The risk of stroke is elevated in pregnancy due to many factors. To date, there have been two reports, totalling five patients, who have undergone mechanical thrombectomy in pregnancy, thus demonstrating the feasibility of the procedure; however, there is no data on the radiation exposure to the mother or foetus related to this therapy. METHODS We highlight the important technical considerations to minimise the risk of the procedure and report the estimated dose received by mother and foetus. We also compare these doses with those received during whole-body CT in trauma and CT pulmonary angiogram (CTPA) examinations. RESULTS Three cases of mechanical thrombectomy were performed at separate tertiary referral neuroscience centres in the UK. Following diagnostic CT and mechanical thrombectomy, the total whole-body effective dose to the pregnant patient was significantly higher than in patients undergoing CTPA (p < 0.05), but not significant different compared to whole-body CT imaging in trauma patients. The estimated dose received by the foetus following diagnostic CT and mechanical thrombectomy was significantly lower than in whole-body imaging in trauma patients at p < 0.05, with no difference in estimated foetal dose compared to CTPA imaging. CONCLUSION The estimated doses received by the foetus during diagnostic stroke imaging and mechanical thrombectomy are equivalent to, or less than, purely diagnostic imaging in emergency situations.
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Affiliation(s)
- George H Tse
- Department of Neuroradiology, Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF, UK.
| | - Vartan Balian
- Department of Neuroradiology, Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF, UK
| | - Paraskevi Charalampatou
- Department of Medical Physics, Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF, UK
| | - Paul Maliakal
- Department of Neuroradiology, Hull Royal Infirmary, Anlaby Road, Hull, HU3 2JZ, UK
| | - Sanjeev Nayak
- Department of Neuroradiology, Royal Stoke University Hospital, Newcastle Road, Stoke on Trent, ST4 6QG, UK
| | - Richard Dyde
- Department of Neuroradiology, Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF, UK
| | - Sanjoy Nagaraja
- Department of Neuroradiology, Sheffield Teaching Hospitals NHS Foundation Trust, Royal Hallamshire Hospital, Glossop Road, Sheffield, S10 2JF, UK
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6
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Lead Shielding in Pediatric Chest CT: Effect of Apron Placement Outside the Scan Volume on Radiation Dose Reduction. AJR Am J Roentgenol 2019; 212:151-156. [DOI: 10.2214/ajr.17.19405] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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7
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Tromeur C, van der Pol LM, Le Roux PY, Ende-Verhaar Y, Salaun PY, Leroyer C, Couturaud F, Kroft LJM, Huisman MV, Klok FA. Computed tomography pulmonary angiography versus ventilation-perfusion lung scanning for diagnosing pulmonary embolism during pregnancy: a systematic review and meta-analysis. Haematologica 2018; 104:176-188. [PMID: 30115658 PMCID: PMC6312023 DOI: 10.3324/haematol.2018.196121] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 08/14/2018] [Indexed: 01/19/2023] Open
Abstract
Differences between computed tomography pulmonary angiography and ventilation-perfusion lung scanning in pregnant patients with suspected acute pulmonary embolism are not well-known, leading to ongoing debate on which test to choose. We searched in PubMed, EMBASE, Web of Science and the Cochrane Library databases and identified all relevant articles and abstracts published up to October 1, 2017. We assessed diagnostic efficiency, frequency of non-diagnostic results and maternal and fetal exposure to radiation exposure. We included 13 studies for the diagnostic efficiency analysis, 30 for the analysis of non-diagnostic results and 22 for the radiation exposure analysis. The pooled rate of false negative test results was 0% for both imaging strategies with overlapping confidence intervals. The pooled rates of non-diagnostic results with computed tomography pulmonary angiography and ventilation-perfusion lung scans were 12% (95% confidence interval: 8-17) and 14% (95% confidence interval: 10-18), respectively. Reported maternal and fetal radiation exposure doses were well below the safety threshold, but could not be compared between the two diagnostic methods given the lack of high quality data. Both imaging tests seem equally safe to rule out pulmonary embolism in pregnancy. We found no significant differences in efficiency and radiation exposures between computed tomography pulmonary angiography and ventilation-perfusion lung scanning although direct comparisons were not possible.
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Affiliation(s)
- Cécile Tromeur
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, the Netherlands .,Groupe d'Etude de la Thrombose de Bretagne Occidentale, University of Brest, Equipe d'Accueil 3878, Department of Internal Medicine and Chest Diseases, CHRU Brest, France.,Centre d'Investigation Clinique INSERM 1412, University of Brest, France
| | - Liselotte M van der Pol
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, the Netherlands.,Department of Internal Medicine, Haga Teaching Hospital, the Hague, the Netherlands
| | | | - Yvonne Ende-Verhaar
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, the Netherlands
| | | | - Christophe Leroyer
- Groupe d'Etude de la Thrombose de Bretagne Occidentale, University of Brest, Equipe d'Accueil 3878, Department of Internal Medicine and Chest Diseases, CHRU Brest, France.,Centre d'Investigation Clinique INSERM 1412, University of Brest, France
| | - Francis Couturaud
- Groupe d'Etude de la Thrombose de Bretagne Occidentale, University of Brest, Equipe d'Accueil 3878, Department of Internal Medicine and Chest Diseases, CHRU Brest, France.,Centre d'Investigation Clinique INSERM 1412, University of Brest, France
| | - Lucia J M Kroft
- Department of Radiology, Leiden University Medical Center, the Netherlands
| | - Menno V Huisman
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, the Netherlands
| | - Frederikus A Klok
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, the Netherlands
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8
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Ryckx N, Sans-Merce M, Schmidt S, Poletti PA, Verdun FR. The use of out-of-plane high Z patient shielding for fetal dose reduction in computed tomography: Literature review and comparison with Monte-Carlo calculations of an alternative optimisation technique. Phys Med 2018; 48:156-161. [PMID: 29631867 DOI: 10.1016/j.ejmp.2018.03.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/29/2018] [Accepted: 03/30/2018] [Indexed: 11/28/2022] Open
Abstract
When performing CT examinations on pregnant patients, great effort should be dedicated towards optimising the exposure of the mother and the conceptus. For this purpose, many radiology departments use high-Z garments to be wrapped around the patient's lower abdomen for out-of-plane organ shielding to protect the fetus. To assess their current protection efficiency, we performed a literature review and compared the efficiencies mentioned in the literature to Monte-Carlo calculations of CT protocols for which the overall scan length was reduced. We found 11 relevant articles, all of them reporting uterus exposure due to CT imaging performed for exclusion of pulmonary embolism, one of the leading causes of peripartum deaths in western countries. Uterus doses ranged between 60 and 660 µGy per examination, and relative dose reductions to the uterus due to high-Z garments were between 20 and 56%. Calculations showed that reducing the scan length by one to three centimetres could potentially reduce uterus dose up to 24% for chest imaging, and even 47% for upper abdominal imaging. These dose reductions were in the order of those achieved by high-Z garments. However, using the latter may negatively influence the diagnostic image quality and even interfere with the automatic exposure control system thus increasing patient dose if positioned in the primary beam, for example in the overranging length in helical acquisition. We conclude that efforts should be concentrated on positioning the patient correctly in the gantry and optimising protocol parameters, rather than using high-Z garments for out-of-plane uterus shielding.
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Affiliation(s)
- Nick Ryckx
- Institute of Radiation Physics, Lausanne University Hospital, Switzerland.
| | - Marta Sans-Merce
- Institute of Radiation Physics, Lausanne University Hospital, Switzerland; Radiology Department, Geneva University Hospital, Switzerland
| | - Sabine Schmidt
- Department of Radiology, Lausanne University Hospital, Switzerland
| | | | - Francis R Verdun
- Institute of Radiation Physics, Lausanne University Hospital, Switzerland
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9
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Rafat Motavalli L, Hoseinian Azghadi E, Miri Hakimabad H, Akhlaghi P. Pulmonary embolism in pregnant patients: Assessing organ dose to pregnant phantom and its fetus during lung imaging. Med Phys 2017; 44:6038-6046. [PMID: 28869670 DOI: 10.1002/mp.12558] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 07/24/2017] [Accepted: 08/25/2017] [Indexed: 11/10/2022] Open
Abstract
PURPOSE The purpose of this study was to provide updated radiation dose from diagnostic exams performed for pregnant patients suspected of pulmonary embolism (PE) using the recently developed BREP phantoms of pregnant woman and the fetus. Also to challenge the validity of current recommendations suggest that ventilation/perfusion (V/Q) single photon emission computed tomography (SPECT) vs. computed tomography pulmonary angiography (CTPA) should be considered for diagnosis of PE in radiosensitive groups such as pregnant women. METHODS The Monte Carlo calculations involving detailed geometrical simulation of pregnant women and the fetus were performed. RESULTS The results showed that when radiation dose to the fetus is of concern, CTPA is more appropriate at early stages causes 50%-97% lower fetal doses for the first two trimesters of pregnancy. While for gestational periods more than 6 months, V/Q SPECT leads to a 15% lower fetal dose and thus, is less hazardous. The fetal dose from CTPA increases with gestational age, while that from V/Q SPECT decreases. Furthermore, the maximum amount of fetal dose is received by fetal skeleton (i.e., on average about 1.8 and 3.9 times larger dose from SPECT and CT, respectively). CONCLUSIONS V/Q SPECT should not always be preferred for pregnant patients suspected of PE. This finding is in contrast with the guidance to choose the preferred modality based on the maternal effective dose. The reason of this issue was discussed in this paper based on chord length distributions (CLDs). The importance of considering fetal organs separately in MC calculations was also highlighted.
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Affiliation(s)
- Laleh Rafat Motavalli
- Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
| | | | - Hashem Miri Hakimabad
- Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Parisa Akhlaghi
- Department of Medical Physics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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Halpenny D, Park B, Alpert J, Latson L, Kim N, Babb J, Shiau M, Ko J. Low dose computed tomography pulmonary angiography protocol for imaging pregnant patients: Can dose reduction be achieved without reducing image quality? Clin Imaging 2017; 44:101-105. [PMID: 28500985 DOI: 10.1016/j.clinimag.2017.03.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/09/2017] [Accepted: 03/29/2017] [Indexed: 12/21/2022]
Abstract
OBJECTIVE To assess the effect of low dose computed tomography pulmonary angiography (CTPA) on radiation dose in pregnant patients. MATERIALS AND METHODS An old CTPA protocol for pregnant patients was compared to a new protocol. Protocol changes included: decreased kVp; increased contrast injection rate; imaging after shallow inspiration. Patients undergoing CTPA before (phase 1 group) or after (phase 2 group) the protocol change, were assessed. RESULTS Effective dose was lower in the phase 2 group (0.95 v 1.66 mSv; p<0.001). Quantitative noise was lower in the phase 1 group (p<0.001). CONCLUSION Low dose CTPA tailored for pregnancy reduces dose in pregnant patients.
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Affiliation(s)
- Darragh Halpenny
- Department of Thoracic Radiology, New York University School of Medicine, 660 1st Ave, NY 10016, USA.
| | - Brian Park
- New York University School of Medicine, 550 1st Avenue, New York, NY 10016, USA
| | - Jeffrey Alpert
- Department of Thoracic Radiology, New York University School of Medicine, 660 1st Ave, NY 10016, USA
| | - Larry Latson
- Department of Thoracic Radiology, New York University School of Medicine, 660 1st Ave, NY 10016, USA
| | - Nancy Kim
- New York University School of Medicine, 550 1st Avenue, New York, NY 10016, USA
| | - James Babb
- Department of Thoracic Radiology, New York University School of Medicine, 660 1st Ave, NY 10016, USA
| | - Maria Shiau
- Department of Thoracic Radiology, New York University School of Medicine, 660 1st Ave, NY 10016, USA
| | - Jane Ko
- Department of Thoracic Radiology, New York University School of Medicine, 660 1st Ave, NY 10016, USA
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11
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van Mens TE, Scheres LJJ, de Jong PG, Leeflang MMG, Nijkeuter M, Middeldorp S. Imaging for the exclusion of pulmonary embolism in pregnancy. Cochrane Database Syst Rev 2017; 1:CD011053. [PMID: 28124411 PMCID: PMC6464730 DOI: 10.1002/14651858.cd011053.pub2] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Pulmonary embolism is a leading cause of pregnancy-related death. An accurate diagnosis in pregnant patients is crucial to prevent untreated pulmonary embolism as well as unnecessary anticoagulant treatment and future preventive measures. Applied imaging techniques might perform differently in these younger patients with less comorbidity and altered physiology, who largely have been excluded from diagnostic studies. OBJECTIVES To determine the diagnostic accuracy of computed tomography pulmonary angiography (CTPA), lung scintigraphy and magnetic resonance angiography (MRA) for the diagnosis of pulmonary embolism during pregnancy. SEARCH METHODS We searched MEDLINE and Embase until July 2015. We used included studies as seeds in citations searches and in 'find similar' functions and searched reference lists. We approached experts in the field to help us identify non-indexed studies. SELECTION CRITERIA We included consecutive series of pregnant patients suspected of pulmonary embolism who had undergone one of the index tests (computed tomography (CT) pulmonary angiography, lung scintigraphy or MRA) and clinical follow-up or pulmonary angiography as a reference test. DATA COLLECTION AND ANALYSIS Two review authors performed data extraction and quality assessment. We contacted investigators of potentially eligible studies to obtain missing information. In the primary analysis, we regarded inconclusive index test results as a negative reference test, and treatment for pulmonary embolism after an inconclusive index test as a positive reference test. MAIN RESULTS We included 11 studies (four CTPA, five lung scintigraphy, two both) with a total of 695 CTPA and 665 lung scintigraphy results. Lung scintigraphy was applied by different techniques. No MRA studies matched our inclusion criteria.Overall, risk of bias and concerns regarding applicability were high in all studies as judged in light of the review research question, as was heterogeneity in study methods. We did not undertake meta-analysis. All studies used clinical follow-up as a reference standard, none in a manner that enabled reliable identification of false positives. Sensitivity and negative predictive value were therefore the only valid test accuracy measures.The median negative predictive value for CTPA was 100% (range 96% to 100%). Median sensitivity was 83% (range 0% to 100%).The median negative predictive value for lung scintigraphy was 100% (range 99% to 100%). Median sensitivity was 100% (range 0% to 100%).The median frequency of inconclusive results was 5.9% (range 0.9% to 36%) for CTPA and 4.0% (range 0% to 23%) for lung scintigraphy. The overall median prevalence of pulmonary embolism was 3.3% (range 0.0% to 8.7%). AUTHORS' CONCLUSIONS Both CTPA and lung scintigraphy seem appropriate for exclusion of pulmonary embolism during pregnancy. However, the quality of the evidence mandates cautious adoption of this conclusion. Important limitations included poor reference standards, necessary assumptions in the analysis regarding inconclusive test results and the inherent inability of included studies to identify false positives. It is unclear which test has the highest accuracy. There is a need for direct comparisons between diagnostic methods, including MR, in prospective randomized diagnostic studies.
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Affiliation(s)
- Thijs E van Mens
- Academic Medical CenterDepartment of Vascular MedicineMeibergdreef 9AmsterdamNetherlands1105 AZ
| | - Luuk JJ Scheres
- Academic Medical CenterDepartment of Vascular MedicineMeibergdreef 9AmsterdamNetherlands1105 AZ
| | - Paulien G de Jong
- Academic Medical CenterDepartment of Vascular MedicineMeibergdreef 9AmsterdamNetherlands1105 AZ
| | - Mariska MG Leeflang
- Academic Medical Center, University of AmsterdamDepartment of Clinical Epidemiology, Biostatistics and BioinformaticsP.O. Box 22700AmsterdamNetherlands1100 DE
| | - Mathilde Nijkeuter
- Academic Medical CenterDepartment of Vascular MedicineMeibergdreef 9AmsterdamNetherlands1105 AZ
- University Medical Centre UtrechtDepartment of Internal MedicineHeidelberglaan 100UtrechtNetherlands3584 CX
| | - Saskia Middeldorp
- Academic Medical CenterDepartment of Vascular MedicineMeibergdreef 9AmsterdamNetherlands1105 AZ
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12
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Ben Abdennebi A, Aubry S, Ounalli L, Fayache MS, Delabrousse E, Petegnief Y. Comparative dose levels between CT-scanner and slot-scanning device (EOS system) in pregnant women pelvimetry. Phys Med 2016; 33:77-86. [PMID: 27993442 DOI: 10.1016/j.ejmp.2016.12.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/14/2016] [Accepted: 12/07/2016] [Indexed: 12/18/2022] Open
Abstract
PURPOSE To estimate fetal absorbed doses for pregnant women pelvimetry, a comparative study between EOS imaging system and low-dose spiral CT-scanner was carried out. For this purpose three different studies were investigated: in vivo, in vitro and Monte Carlo calculations. METHODS In vivo dosimetry was performed, using OSL NanoDot dosimeters, to determine the dose to the skin of twenty pregnant women. In vitro studies were established by using a cubic phantom of water, in order to estimate the out of field doses. In the latter study, OSLDs were placed at depths corresponding to the lowest, average and highest position of the uterus. Monte Carlo calculations of effective doses to high radio-sensitive organs were established, using PCXMC and CTExpo software suites for EOS imaging system and CT-scanner, respectively. RESULTS The EOS imaging system reduces radiation exposure 4 to 8 times compared to the CT-scanner. The entrance skin doses were 74% (p-values <0.01) higher with the CT-scanner than with the EOS system. In the out of field region, the measured doses of the EOS system were reduced by 80% (p-values <0.02). Monte Carlo calculations confirmed that effective doses to organs are less accentuated for EOS than for CT pelvimetry. CONCLUSIONS The EOS system is less irradiating than the CT exam. The out-of-field dose which is significant, is lower in the EOS than in the CT-scanner and could be reduced even further by optimizing the time used for image acquisition.
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Affiliation(s)
- A Ben Abdennebi
- Regional and University Hospital of Besançon, 25000 Besançon, France; Faculty of Mathematical, Physical and Natural Sciences of Tunis, 2092 El Manar, Tunis, Tunisia; Laboratory on Energy and Matter for Nuclear Sciences Development, LR16CNSTN02, Tunisia
| | - S Aubry
- Regional and University Hospital of Besançon, 25000 Besançon, France; Nanomedicine Lab Imagery and Therapeutics EA 4662, University of Franche-Comte, 25000 Besancon, France
| | - L Ounalli
- National Center for Nuclear Sciences and Technology, 2020 Ariana, Tunisia; Laboratory on Energy and Matter for Nuclear Sciences Development, LR16CNSTN02, Tunisia.
| | - M S Fayache
- Faculty of Mathematical, Physical and Natural Sciences of Tunis, 2092 El Manar, Tunis, Tunisia; Laboratory on Energy and Matter for Nuclear Sciences Development, LR16CNSTN02, Tunisia
| | - E Delabrousse
- Regional and University Hospital of Besançon, 25000 Besançon, France; Nanomedicine Lab Imagery and Therapeutics EA 4662, University of Franche-Comte, 25000 Besancon, France
| | - Y Petegnief
- Regional and University Hospital of Besançon, 25000 Besançon, France
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Metz TD, Khanna A. Evaluation and Management of Maternal Cardiac Arrhythmias. Obstet Gynecol Clin North Am 2016; 43:729-745. [PMID: 27816157 DOI: 10.1016/j.ogc.2016.07.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pregnant women often complain of palpitations. The differential diagnosis for new-onset palpitations in pregnancy ranges from benign conditions to life-threatening arrhythmias. Maternal arrhythmias can occur in isolation or in the setting of underlying structural heart disease. Optimal management of maternal cardiac arrhythmias includes identification of the specific arrhythmia, diagnosis of comorbid conditions, and appropriate intervention. In general, management of maternal cardiac arrhythmias is similar to that of the general population. Special consideration must be given as to the effects of medications and procedures on both the mother and fetus to optimize outcomes. The importance of multidisciplinary care with cardiology, obstetrics, and anesthesia is emphasized.
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Affiliation(s)
- Torri D Metz
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, 12631 East 17th Avenue, Aurora, CO 80045, USA; Department of Obstetrics and Gynecology, Denver Health Medical Center, 777 Bannock Street, MC 0660, Denver, CO 80204, USA.
| | - Amber Khanna
- Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, 12401 East 17th Avenue, Aurora, CO 80045, USA
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Matsunaga Y, Kawaguchi A, Kobayashi M, Suzuki S, Suzuki S, Chida K. Radiation doses for pregnant women in the late pregnancy undergoing fetal-computed tomography: a comparison of dosimetry and Monte Carlo simulations. Radiol Phys Technol 2016; 10:148-154. [PMID: 27645287 DOI: 10.1007/s12194-016-0377-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 09/07/2016] [Accepted: 09/08/2016] [Indexed: 10/21/2022]
Abstract
The purposes of this study were (1) to compare the radiation doses for 320- and 80-row fetal-computed tomography (CT), estimated using thermoluminescent dosimeters (TLDs) and the ImPACT Calculator (hereinafter referred to as the "CT dosimetry software"), for a woman in her late pregnancy and her fetus and (2) to estimate the overlapped fetal radiation dose from a 320-row CT examination using two different estimation methods of the CT dosimetry software. The direct TLD data in the present study were obtained from a previous study. The exposure parameters used for TLD measurements were entered into the CT dosimetry software, and the appropriate radiation dose for the pregnant woman and her fetus was estimated. When the whole organs (e.g., the colon, small intestine, and ovaries) and the fetus were included in the scan range, the difference in the estimated doses between the TLD measurement and the CT dosimetry software measurement was <1 mGy (<23 %) in both CT units. In addition, when the whole organs were within the scan range, the CT dosimetry software was used for evaluating the fetal radiation dose and organ-specific doses for the woman in the late pregnancy. The conventional method using the CT dosimetry software cannot take into account the overlap between volumetric sections. Therefore, the conventional method using a 320-row CT unit in a wide-volume mode might result in the underestimation of radiation doses for the fetus and the colon, small intestine, and ovaries.
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Affiliation(s)
- Yuta Matsunaga
- Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan. .,Department of Imaging, Nagoya Kyoritsu Hospital, 1-172, Hokke, Nakagawa-ku, Nagoya, Aichi, 454-0933, Japan.
| | - Ai Kawaguchi
- Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan.,Department of Radiology, TOYOTA Memorial Hospital, 1-1 Heiwa-cho, Toyota, Aichi, 471-0821, Japan
| | - Masanao Kobayashi
- School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Shigetaka Suzuki
- School of Medicine, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Shoichi Suzuki
- School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Koichi Chida
- Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
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15
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Gomes M, Matias A, Macedo F. Risks to the fetus from diagnostic imaging during pregnancy: review and proposal of a clinical protocol. Pediatr Radiol 2015; 45:1916-29. [PMID: 26271622 DOI: 10.1007/s00247-015-3403-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 04/25/2015] [Accepted: 06/01/2015] [Indexed: 11/25/2022]
Abstract
Every day, medical practitioners face the dilemma of exposing pregnant or possibly pregnant patients to radiation from diagnostic examinations. Both doctors and patients often have questions about the risks of radiation. The most vulnerable period is between the 8th and 15th weeks of gestation. Deterministic effects like pregnancy loss, congenital malformations, growth retardation and neurobehavioral abnormalities have threshold doses above 100-200 mGy. The risk is considered negligible at 50 mGy and in reality no diagnostic examination exceeds this limit. The risk of carcinogenesis is slightly higher than in the general population. Intravenous iodinated contrast is discouraged, except in highly selected patients. Considering all the possible noxious effects of radiation exposure, measures to diminish radiation are essential and affect the fetal outcome. Nonionizing procedures should be considered whenever possible and every radiology center should have its own data analysis on fetal radiation exposure. In this review, we analyze existing literature on fetal risks due to radiation exposure, producing a clinical protocol to guide safe radiation use in a clinical setting.
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Affiliation(s)
- Mafalda Gomes
- Faculty of Medicine, University of Porto, Praça de Gomes Teixeira, 4099-002, Porto, Portugal.
| | - Alexandra Matias
- Faculty of Medicine, University of Porto, Praça de Gomes Teixeira, 4099-002, Porto, Portugal
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Kelaranta A, Kaasalainen T, Seuri R, Toroi P, Kortesniemi M. Fetal radiation dose in computed tomography. RADIATION PROTECTION DOSIMETRY 2015; 165:226-230. [PMID: 25836690 DOI: 10.1093/rpd/ncv097] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The connection between recorded volumetric CT dose index (CTDI vol) and determined mean fetal dose (Df) was examined from metal-oxide-semiconductor field-effect transistor dose measurements on an anthropomorphic female phantom in four stages of pregnancy in a 64-slice CT scanner. Automated tube current modulation kept the mean Df fairly constant through all pregnancy stages in trauma (4.4-4.9 mGy) and abdomino-pelvic (2.1-2.4 mGy) protocols. In pulmonary angiography protocol, the mean Df increased exponentially as the distance from the end of the scan range decreased (0.01-0.09 mGy). For trauma protocol, the relative mean Df as a function of gestational age were in the range 0.80-0.97 compared with the mean CTDI vol. For abdomino-pelvic protocol, the relative mean Df was 0.57-0.79 and for pulmonary angiography protocol, 0.01-0.05 compared with the mean CTDI vol, respectively. In conclusion, if the fetus is in the primary beam, the CTDI vol can be used as an upper estimate of the fetal dose. If the fetus is not in the primary beam, the fetal dose can be estimated by considering also the distance of the fetus from the scan range.
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Affiliation(s)
- Anna Kelaranta
- HUS Medical Imaging Center, University of Helsinki and Helsinki University Hospital, PO Box 340, FI-00290 Helsinki, Finland Department of Physics, University of Helsinki, PO Box 64, FI-00014 Helsinki, Finland
| | - Touko Kaasalainen
- HUS Medical Imaging Center, University of Helsinki and Helsinki University Hospital, PO Box 340, FI-00290 Helsinki, Finland Department of Physics, University of Helsinki, PO Box 64, FI-00014 Helsinki, Finland
| | - Raija Seuri
- HUS Medical Imaging Center, University of Helsinki and Helsinki University Hospital, PO Box 340, FI-00290 Helsinki, Finland
| | - Paula Toroi
- STUK - Radiation and Nuclear Safety Authority, Laippatie 4, PO Box 14, FI-00881 Helsinki, Finland
| | - Mika Kortesniemi
- HUS Medical Imaging Center, University of Helsinki and Helsinki University Hospital, PO Box 340, FI-00290 Helsinki, Finland Department of Physics, University of Helsinki, PO Box 64, FI-00014 Helsinki, Finland
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Weber N, Monnin P, Elandoy C, Ding S. A model-based approach of scatter dose contributions and efficiency of apron shielding for radiation protection in CT. Phys Med 2015; 31:889-896. [PMID: 26112350 DOI: 10.1016/j.ejmp.2015.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 06/02/2015] [Accepted: 06/05/2015] [Indexed: 11/19/2022] Open
Abstract
Given the contribution of scattered radiations to patient dose in CT, apron shielding is often used for radiation protection. In this study the efficiency of apron was assessed with a model-based approach of the contributions of the four scatter sources in CT, i.e. external scattered radiations from the tube and table, internal scatter from the patient and backscatter from the shielding. For this purpose, CTDI phantoms filled with thermoluminescent dosimeters were scanned without apron, and then with an apron at 0, 2.5 and 5 cm from the primary field. Scatter from the tube was measured separately in air. The scatter contributions were separated and mathematically modelled. The protective efficiency of the apron was low, only 1.5% in scatter dose reduction on average. The apron at 0 cm from the beam lowered the dose by 7.5% at the phantom bottom but increased the dose by 2% at the top (backscatter) and did not affect the centre. When the apron was placed at 2.5 or 5 cm, the results were intermediate to the one obtained with the shielding at 0 cm and without shielding. The apron effectiveness is finally limited to the small fraction of external scattered radiation.
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Affiliation(s)
- N Weber
- University of Applied Sciences, Haute Ecole de Santé Vaud, Av. Beaumont 21, 1011 Lausanne, Switzerland; University Hospital of Lausanne (CHUV), Rue du Bugnon 46, 1011 Lausanne, Switzerland
| | - P Monnin
- University of Applied Sciences, Haute Ecole de Santé Vaud, Av. Beaumont 21, 1011 Lausanne, Switzerland
| | - C Elandoy
- University Hospital of Lausanne (CHUV), Rue du Bugnon 46, 1011 Lausanne, Switzerland
| | - S Ding
- University of Applied Sciences, Haute Ecole de Santé Vaud, Av. Beaumont 21, 1011 Lausanne, Switzerland.
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Moriarty JM, Bolster F, O'Connor C, Fitzpatrick P, Lawler LP, Kavanagh EC, MacMahon PJ, Murray JG. Frequency of nonthromboembolic imaging abnormalities in pregnant women referred for computed tomography pulmonary arteriography. Can Assoc Radiol J 2015; 66:24-9. [PMID: 25623008 DOI: 10.1016/j.carj.2014.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 10/07/2014] [Accepted: 11/26/2014] [Indexed: 11/30/2022] Open
Abstract
PURPOSE The study sought to determine the frequency of nonthromboembolic imaging abnormalities in pregnant women referred for computed tomography pulmonary arteriography (CTPA). MATERIALS AND METHODS CTPA studies on 100 consecutive pregnant women performed over a 5-year period were reviewed independently by 2 radiologists, with conflicts resolved by consensus. Age range was 18-43 years (mean 28 years). The presence or absence of pulmonary embolism and of nonthromboembolic imaging abnormalities was recorded. These were graded as A if the abnormalities were thought to provide potential alternative explanations for acute symptoms, B if findings were incidental that required clinical or radiologic follow-up, and C if the findings did not require further action. RESULTS Pulmonary embolism was seen in 5 women. In 2 of these additional findings of consolidation and infarction were seen. Ninety-five women did not have pulmonary embolism. Eleven women (12%) had grade A abnormalities; 6 cases of consolidation, 2 cases of lobar collapse, and 3 cases of heart failure with pleural effusions. One woman had a grade B abnormality due to the presence of pulmonary nodules. Ten women had incidental grade C abnormalities. CONCLUSION Pulmonary embolism occurs in 5% of pregnant women referred for CTPA. In pregnant women without embolism on CTPA, potential alternative causes for patient symptoms are seen on CT in 12% of cases.
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Affiliation(s)
- John M Moriarty
- David Geffen School of Medicine at UCLA, Diagnostic Cardiovascular Imaging, Los Angeles, California, USA
| | - Ferdia Bolster
- Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland.
| | - Clare O'Connor
- Department of Obstetrics and Gynaecology, The Rotunda Hospital, Dublin, Ireland
| | - Patricia Fitzpatrick
- School of Public Health and Population Science, University College Dublin, Dublin, Ireland
| | - Leo P Lawler
- Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland
| | - Eoin C Kavanagh
- Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland
| | - Peter J MacMahon
- Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland
| | - John G Murray
- Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland
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19
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Perisinakis K, Seimenis I, Tzedakis A, Damilakis J. Perfusion Scintigraphy Versus 256-Slice CT Angiography in Pregnant Patients Suspected of Pulmonary Embolism: Comparison of Radiation Risks. J Nucl Med 2014; 55:1273-80. [DOI: 10.2967/jnumed.114.137968] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 04/25/2014] [Indexed: 11/16/2022] Open
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Chatterson LC, Leswick DA, Fladeland DA, Hunt MM, Webster S, Lim H. Fetal shielding combined with state of the art CT dose reduction strategies during maternal chest CT. Eur J Radiol 2014; 83:1199-1204. [PMID: 24838282 DOI: 10.1016/j.ejrad.2014.04.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 04/14/2014] [Accepted: 04/15/2014] [Indexed: 11/29/2022]
Abstract
PURPOSE Custom bismuth-antimony shields were previously shown to reduce fetal dose by 53% on an 8DR (detector row) CT scanner without dynamic adaptive section collimation (DASC), automatic tube current modulation (ATCM) or adaptive statistical iterative reconstruction (ASiR). The purpose of this study is to compare the effective maternal and average fetal organ dose reduction both with and without bismuth-antimony shields on a 64DR CT scanner using DASC, ATCM and ASiR during maternal CTPA. MATERIALS AND METHODS A phantom with gravid prosthesis and a bismuth-antimony shield were used. Thermoluminescent dosimeters (TLDs) measured fetal radiation dose. The average fetal organ dose and effective maternal dose were determined using 100 kVp, scanning from the lung apices to the diaphragm utilizing DASC, ATCM and ASiR on a 64DR CT scanner with and without shielding in the first and third trimester. Isolated assessment of DASC was done via comparing a new 8DR scan without DASC to a similar scan on the 64DR with DASC. RESULTS Average third trimester unshielded fetal dose was reduced from 0.22 mGy ± 0.02 on the 8DR to 0.13 mGy ± 0.03 with the conservative 64DR protocol that included 30% ASiR, DASC and ATCM (42% reduction, P<0.01). Use of a shield further reduced average third trimester fetal dose to 0.04 mGy ± 0.01 (69% reduction, P<0.01). The average fetal organ dose reduction attributable to DASC alone was modest (6% reduction from 0.17 mGy ± 0.02 to 0.16 mGy ± 0.02, P=0.014). First trimester fetal organ dose on the 8DR protocol was 0.07 mGy ± 0.03. This was reduced to 0.05 mGy ± 0.03 on the 64DR protocol without shielding (30% reduction, P=0.009). Shields further reduced this dose to below accurately detectable levels. Effective maternal dose was reduced from 4.0 mSv on the 8DR to 2.5 mSv on the 64DR scanner using the conservative protocol (38% dose reduction). CONCLUSION ASiR, ATCM and DASC combined significantly reduce effective maternal and fetal organ dose during CTPA. Shields continue to be an effective means of fetal dose reduction.
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Affiliation(s)
| | - David A Leswick
- Department of Diagnostic Imaging, University of Saskatchewan, Canada
| | - Derek A Fladeland
- Department of Diagnostic Imaging, University of Saskatchewan, Canada
| | - Megan M Hunt
- Saskatchewan Ministry of Labour Relations and Workplace Safety, Canada
| | - Stephen Webster
- Saskatchewan Ministry of Labour Relations and Workplace Safety, Canada
| | - Hyun Lim
- Department of Community Health and Epidemiology, College of Medicine, University of Saskatchewan, Canada
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22
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Conti E, Zezza L, Ralli E, Comito C, Sada L, Passerini J, Caserta D, Rubattu S, Autore C, Moscarini M, Volpe M. Pulmonary embolism in pregnancy. J Thromb Thrombolysis 2013; 37:251-70. [DOI: 10.1007/s11239-013-0941-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Osei EK, Darko J. Foetal radiation dose and risk from diagnostic radiology procedures: a multinational study. ISRN RADIOLOGY 2012; 2013:318425. [PMID: 24959554 PMCID: PMC4045527 DOI: 10.5402/2013/318425] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 07/08/2012] [Indexed: 11/23/2022]
Abstract
In diagnostic radiology examinations there is a benefit that the patient derives from the resulting diagnosis. Given that so many examinations are performed each year, it is inevitable that there will be occasions when an examination(s) may be inadvertently performed on pregnant patients or occasionally it may become clinically necessary to perform an examination(s) on a pregnant patient. In all these circumstances it is necessary to request an estimation of the foetal dose and risk. We initiated a study to investigate fetal doses from different countries. Exposure techniques on 367 foetuses from 414 examinations were collected and investigated. The FetDoseV4 program was used for all dose and risk estimations. The radiation doses received by the 367 foetuses ranges: <0.001-21.9 mGy depending on examination and technique. The associated probability of induced hereditary effect ranges: <1 in 200000000 (5 × 10(-9)) to 1 in 10000 (1 × 10(-4)) and the risk of childhood cancer ranges <1 in 12500000 (8 × 10(-8)) to 1 in 500 (2 × 10(-3)). The data indicates that foetal doses from properly conducted diagnostic radiology examinations will not result in any deterministic effect and a negligible risk of causing radiation induced hereditary effect in the descendants of the unborn child.
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Affiliation(s)
- Ernest K. Osei
- Department of Medical Physics, Grand River Regional Cancer Center, Kitchener, Canada N2G 1G3
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Canada N2L 3G1
| | - Johnson Darko
- Cancer Center of Southeastern Ontario, Kingston General Hospital, Kingston, Canada K7L 5P9
- Department of Oncology, Queens University, Kingston, Canada K7L 5P9
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Iball GR, Brettle DS. Organ and effective dose reduction in adult chest CT using abdominal lead shielding. Br J Radiol 2011; 84:1020-6. [PMID: 22011831 DOI: 10.1259/bjr/53865832] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES The purpose of this study was to evaluate and compare organ and effective dose savings that could be achieved using conventional lead aprons and a new, custom-designed shield as out-of-plane shielding devices during chest CT scans. METHODS Thermoluminescent dosimeters were used to measure doses throughout the abdomen and pelvis during CT scans of the chest of a RANDO phantom. Dose measurements were made with no shielding, with lead aprons and with the new shield around the abdomen and pelvis in order to quantify the achievable organ and effective dose reductions. RESULTS Average dose savings in the 10 phantom sections ranged from 5% to 78% with the highest point dose saving of 93% being found in the mid-pelvis. When shielding was used, the maximum measured organ dose reduction was a 72% dose saving to the testes. Significant dose savings were found throughout the abdomen and pelvis, which contributed to an effective dose saving of 4% that was achieved over and above the dose savings obtained through conventional optimisation strategies. This could yield significant population dose savings and reductions in collective radiation risk. CONCLUSION In this study significant organ and effective dose reductions have been achieved through the use of abdominal shielding during chest CT examinations and it is therefore recommended that out-of-plane patient shielding devices should be used for all chest CT scans and potentially for every CT scan, irrespective of body part.
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Affiliation(s)
- G R Iball
- Department of Medical Physics & Engineering, Old Medical School, Leeds General Infirmary, Leeds, UK.
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25
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Rajaram S, Exley CE, Fairlie F, Matthews S. Effect of antenatal iodinated contrast agent on neonatal thyroid function. Br J Radiol 2011; 85:e238-42. [PMID: 22167515 DOI: 10.1259/bjr/29806327] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
OBJECTIVE The aim of this study was to assess the effect on neonatal thyroid function of iodinated contrast media administered for CT pulmonary angiography (CTPA) in babies whose mothers were investigated for suspected pulmonary embolism during pregnancy. METHODS Retrospective review of 115 pregnant patients investigated for suspected pulmonary embolism. The patient cohort consisted of two groups: Group A consisted of 73 pregnant females who received iodinated contrast agent for CTPA, and Group B (control group) consisted of 42 pregnant females who were investigated by perfusion imaging only. The results of the neonatal thyroid function tests for the babies of the mothers in Groups A and B were compared. RESULTS All of the neonatal thyroid function tests for both groups were normal with no statistical difference between the two groups. CONCLUSION No adverse effect on thyroid function was demonstrated in neonates exposed to in utero iodinated contrast media. However, as our study involves a small patient group, the results should be interpreted with caution.
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Affiliation(s)
- S Rajaram
- Department of Radiology, Sheffield Teaching Hospital Trust, Sheffield, UK.
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Dauer LT, Thornton RH, Miller DL, Damilakis J, Dixon RG, Marx MV, Schueler BA, Vañó E, Venkatesan A, Bartal G, Tsetis D, Cardella JF. Radiation management for interventions using fluoroscopic or computed tomographic guidance during pregnancy: a joint guideline of the Society of Interventional Radiology and the Cardiovascular and Interventional Radiological Society of Europe with Endorsement by the Canadian Interventional Radiology Association. J Vasc Interv Radiol 2011; 23:19-32. [PMID: 22112899 DOI: 10.1016/j.jvir.2011.09.007] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 09/08/2011] [Accepted: 09/08/2011] [Indexed: 12/16/2022] Open
Affiliation(s)
- Lawrence T Dauer
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
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Iball GR, Brettle DS. Patient and radiographer perspectives of two lead shielding devices for foetal dose reduction in CT scanning. Radiography (Lond) 2011. [DOI: 10.1016/j.radi.2011.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Chatterson LC, Leswick DA, Fladeland DA, Hunt MM, Webster ST. Lead versus Bismuth-Antimony Shield for Fetal Dose Reduction at Different Gestational Ages at CT Pulmonary Angiography. Radiology 2011; 260:560-7. [DOI: 10.1148/radiol.11101575] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Abstract
Pregnancy is an example of Virchow's triad predisposing to the development of venous thromboembolism (VTE). Specific risk factors for antepartum and postpartum VTE have been identified. The diagnosis of pulmonary embolism in pregnancy is complicated by the physiologic changes of pregnancy as well as physicians' apprehension about ordering radiologic studies during pregnancy because of concerns with fetal well-being. Therapy for VTE is complicated by pregnancy physiology affecting medication pharmacokinetics and bioavailability, and the unpredictable occurrence of labor during therapeutic anticoagulation.
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Affiliation(s)
- Margaret A Miller
- Division of Obstetric and Consultative Medicine, Women and Infants' Hospital of Rhode Island, The Warren Alpert Medical School of Brown University, 100 Dudley Street, Suite 1100, Providence, RI 02905, USA.
| | - Michel Chalhoub
- Department of Medicine, Pulmonary and Critical Care Medicine, Staten Island University Hospital, 475 Seaview Avenue, Staten Island, NY 10305, USA
| | - Ghada Bourjeily
- Pulmonary and Critical Care Medicine, Department of Medicine, Women and Infants' Hospital of Rhode Island, The Warren Alpert Medical School of Brown University, 100 Dudley Street, Suite 1100, Providence, RI 02905, USA
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Fetal Radiation Dose During Gestation Estimated on an Anthropomorphic Phantom for Three Generations of CT Scanners. AJR Am J Roentgenol 2011; 196:1133-7. [DOI: 10.2214/ajr.10.4497] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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31
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Iball GR, Brettle DS. Use of lead shielding on pregnant patients undergoing CT scans: Results of an international survey. Radiography (Lond) 2011. [DOI: 10.1016/j.radi.2010.12.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Fogerty AE, Connors JM. Treating Venous Thromboembolism in Pregnancy. Hematol Oncol Clin North Am 2011; 25:379-91, ix. [DOI: 10.1016/j.hoc.2011.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Body CT during pregnancy: utilization trends, examination indications, and fetal radiation doses. AJR Am J Roentgenol 2011; 196:146-51. [PMID: 21178060 DOI: 10.2214/ajr.10.4271] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE The objective of our study was to analyze body CT utilization trends, indications, fetal radiation doses, and scanning parameters associated with high fetal radiation doses (defined as > 30 mGy). MATERIALS AND METHODS A retrospective review of all chest and abdominopelvic CT examinations performed between 1998 and 2005 of patients known to be pregnant was conducted. Demographics, gestational age, examination indication, and scan parameters were recorded. Fetal radiation dose was calculated for those abdominopelvic examinations with direct fetal irradiation. RESULTS From a database of more than 170,000 chest and more than 180,000 abdominopelvic CT examinations, 74 chest and 86 abdominopelvic examinations of pregnant patients were identified. Chest CT use increased on average 75%/y/1,000 deliveries in pregnancy versus 19%/y increase in all patients (p = 0.2700). Abdominopelvic CT utilization increase was on average 22%/y/1,000 deliveries in pregnant patients versus 13%/y increase in all patients (p = 0.1865). The most common indication for chest CT during pregnancy was suspected pulmonary embolism (85%, 63/74) and for abdominopelvic CT, suspected appendicitis (58%, 50/86). The average fetal dose from abdominopelvic CT was 24.8 mGy (range, 6.7-56 mGy); one examination exceeded the 50-mGy threshold for increased risk of childhood cancer. Scanning parameters associated with a dose of more than 30 mGy were a pitch of less than 1 (p = 0.0080) and more than one series acquisition (p = 0.0136). CONCLUSION Growth of CT during pregnancy reflects the trend of increased CT utilization in the general population. Avoiding use of CT in pregnant patients with suspected appendicitis would significantly decrease fetal radiation exposure. Abdominopelvic CT during pregnancy should be carefully planned and monitored so as not to exceed the fetal radiation dose for negligible risk.
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Schembri GP, Miller AE, Smart R. Radiation dosimetry and safety issues in the investigation of pulmonary embolism. Semin Nucl Med 2011; 40:442-54. [PMID: 20920634 DOI: 10.1053/j.semnuclmed.2010.07.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
When considering the investigation of the patient with possible pulmonary embolism, one needs to balance the likelihood of disease and the diagnostic utility of the test against the risks associated with the investigation. Both computed tomography pulmonary angiography (CTPA) and the ventilation/perfusion (V/Q) scan involve exposure to ionizing radiation. The effect of low-level ionizing radiation remains an issue of some controversy. CTPA delivers a greater effective dose and, in particular, greater doses to breast tissue, than the V/Q scan (typically 10-70 mGy for CTPA vs <1.5 mGy for V/Q to breast). Since breast tissue is particularly radiosensitive in younger women, the V/Q study has an advantage over CTPA in this group. In the pregnant patient, fetal exposure has been raised as a concern. In fact, there is typically only low fetal exposure from either study (<1 mGy). The CTPA does deliver less fetal exposure, particularly in the first trimester, but the difference between CTPA and V/Q scan is small when compared with the difference in dose to maternal breast from the 2 investigations. The "as low as reasonably achievable" (ie, ALARA) principle favors the use of V/Q scans in young women, assuming the diagnostic power of the 2 tests is comparable. CTPA requires a contrast injection that can cause adverse reactions in a small number of patients. No significant risk, however, has been demonstrated with the radiopharmaceuticals involved in V/Q scans.
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Affiliation(s)
- Geoffrey P Schembri
- Department of Nuclear Medicine, Royal North Shore Hospital, St Leonards, NSW, Australia.
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Revel MP, Cohen S, Sanchez O, Collignon MA, Thiam R, Redheuil A, Meyer G, Frija G. Pulmonary embolism during pregnancy: diagnosis with lung scintigraphy or CT angiography? Radiology 2010; 258:590-8. [PMID: 21131583 DOI: 10.1148/radiol.10100986] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE To evaluate the rate of positive, negative, and indeterminate results and the agreement between initial and expert readings for lung scintigraphy and computed tomographic (CT) angiography performed in patients suspected of having pulmonary embolism (PE) during pregnancy. MATERIALS AND METHODS Institutional review board approval was obtained. The authors retrospectively analyzed the images from lung scintigraphy and CT angiography performed in pregnant patients during the past 9 years. Images from 46 CT angiographic examinations performed in 43 patients and 91 of 94 lung scintigraphic examinations were reviewed by experts, whose readings were then compared with the initial reports. For CT angiography, the quality of opacification was graded as good, suboptimal, or poor and intraarterial attenuation was measured. RESULTS The rates of positive findings (seven of 43 patients [16%] with CT angiography and 10 of 91 patients [11%] with scintigraphy, P = .36), negative findings (28 of 43 patients [65%] with CT angiography and 64 of 91 patients [70%] with scintigraphy, P = .54), and indeterminate findings (eight of 43 patients [19%] with CT angiography and 17 of 91 patients [19%] with scintigraphy, P = .99) were similar for CT angiography and lung scintigraphy. There were four discrepancies between initial and expert readings for CT angiography (κ = 0.84; confidence interval: 0.68, 0.99) and 14 for lung scintigraphy (κ = 0.75; 95% confidence interval: 0.63, 0.87). Opacification was classified as good for only 23 of the 46 CT angiographic examinations (50%). Attenuation values were significantly different among the groups with good, suboptimal, or poor opacification. Alternative diagnoses unsuspected at chest radiography were demonstrated at CT angiography in five of the 43 patients (12%). The mean maternal radiation dose was 0.9 mSv for lung scintigraphy and 7.3 mSv for CT angiography. CONCLUSION Lung scintigraphy and CT angiography have comparable performances for PE diagnosis during pregnancy. Interobserver agreement is better for CT angiography, which also enables alternative diagnosis of unsuspected disease but delivers higher maternal radiation dose.
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Affiliation(s)
- Marie-Pierre Revel
- Departments of Radiology, Pompidou Hospital, Université Paris Descartes, 20 rue Leblanc, 75015 Paris, France.
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Niemann T, Nicolas G, Roser HW, Müller-Brand J, Bongartz G. Imaging for suspected pulmonary embolism in pregnancy-what about the fetal dose? A comprehensive review of the literature. Insights Imaging 2010; 1:361-372. [PMID: 22347929 PMCID: PMC3259315 DOI: 10.1007/s13244-010-0043-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 08/13/2010] [Accepted: 09/15/2010] [Indexed: 02/08/2023] Open
Abstract
OBJECTIVE: To give a comprehensive overview of fetal doses reported in the literature when imaging the pregnant woman with suspected pulmonary embolism (PE). METHODS: A comprehensive literature search in the PubMed, MEDLINE and EMBASE databases yielded a total of 1,687 papers that were included in the analysis and have been analysed with regard to fetal dose in suspected PE radiological imaging strategies. RESULTS: Fetal dose in chest computed tomography (CT) ranges between 0.013 and 0.026 mGy in early and 0.06-0.1 mGy in late pregnancy compared with 99mTc-MAA perfusion scintigraphy with a fetal dose of 0.1-0.6 mGy in early and 0.6-0.8 mGy in late pregnancy. (99m)Tc-aerosol ventilation scintigraphy results in 0.1-0.3 mGy. However, there is concern about female breast irradiation in CT, which is higher than in scintigraphy. CT radiation risks for breast tissue remain unclear. CONCLUSION: Knowledge of dosimetry and radiation risks is crucial in the radiological work-up of suspected PE in pregnancy. It is reasonable to reserve scintigraphy for pregnant patients with normal chest radiography findings and no history of asthma or chronic lung disease. Performing CT applying dose reduction instead of scintigraphy will minimise fetal radiation dose and maximise the diagnostic value.
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Assessment of the alveolar-arterial oxygen gradient as a screening test for pulmonary embolism in pregnancy. Am J Obstet Gynecol 2010; 203:373.e1-4. [PMID: 20554265 DOI: 10.1016/j.ajog.2010.04.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2010] [Revised: 03/29/2010] [Accepted: 04/29/2010] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The objective of the study was to determine whether the alveolar-arterial (A-a) oxygen gradient is an adequate screening test for pulmonary embolism (PE) in pregnancy and postpartum. STUDY DESIGN A chart review was performed at Tampa General Hospital. Patients who had a workup for a PE consisting of a computed tomography pulmonary angiogram and an arterial blood gas from 2002 to 2009 were included in the analysis. Sensitivity, specificity, and negative and positive predictive values were calculated. Additionally, common clinical signs and symptoms were assessed for their ability to accurately predict PE. RESULTS Of 102 patients, there were 13 PEs (2 antepartum and 11 postpartum). The best sensitivity, specificity, and negative and positive predictive values for A-a gradients were 76.9%, 20.2%, 80.0%, and 11.5%, respectively. CONCLUSION The A-a gradient is a poor screening test for PE in pregnancy and postpartum. Suspicion of PE should prompt early imaging studies to rapidly make the diagnosis and begin treatment.
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Wieseler KM, Bhargava P, Kanal KM, Vaidya S, Stewart BK, Dighe MK. Imaging in Pregnant Patients: Examination Appropriateness. Radiographics 2010; 30:1215-29; discussion 1230-3. [DOI: 10.1148/rg.305105034] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
OBJECTIVE The purpose of this article is to develop a method for estimating embryo doses in CT. MATERIALS AND METHODS Absorbed doses to the uterus (embryo) of a 70-kg woman were estimated using the ImPACT CT Patient Dosimetry Calculator. For a particular CT scan length, relative uterus doses and normalized plateau uterus doses were determined for a range of commercial CT scanners. Patient size characteristics were obtained from cross-sectional axial images of 100 consecutive patients (healthy women undergoing unenhanced pelvic CT examinations). For each patient, the diameter of a water cylinder with the same mass as the patient's pelvis was computed. Relative dose values were generated for cylinder diameters ranging from 16 to 36 cm at x-ray tube voltages between 80 and 140 kV. RESULTS Values of relative uterus dose increased monotonically with increasing scan length, independently of scanner model, and reached a plateau for scan lengths greater than approximately 50 cm. The average normalized plateau uterus dose for all scanners was approximately 1.4 and showed interscanner differences of less than 10% for modern scanners operated at 120 kV. Normalized plateau doses show little dependence on the x-ray tube voltage used to perform the CT examination. Our results show that the uterus dose estimate in an abdominal or pelvis CT examination performed on a 70-kg patient is about 40% higher than the reported value of the volume CT dose index (CTDI(vol)). The pelvis of a 70-kg patient may be modeled as a water cylinder with a diameter of 28 cm and has an average anteroposterior dimension of 22 cm. For constant CT technique factors, embryo dose estimates for a 45-kg patient would be approximately 18% higher than those for a 70-kg patient, whereas the corresponding dose estimates in a 120-kg patient would be approximately 37% lower. CONCLUSION Embryo doses can be estimated using relative uterus doses, normalized plateau uterus doses, and CTDI(vol) data with correction factors for patient size.
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Hartmann IJ, Wittenberg R, Schaefer-Prokop C. Imaging of acute pulmonary embolism using multi-detector CT angiography: An update on imaging technique and interpretation. Eur J Radiol 2010; 74:40-9. [DOI: 10.1016/j.ejrad.2010.02.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 02/09/2010] [Indexed: 11/27/2022]
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Abstract
Pulmonary embolism (PE) is the leading cause of maternal mortality in the developed world. Mortality from PE in pregnancy might be related to challenges in targeting the right population for prevention, ensuring that diagnosis is suspected and adequately investigated, and initiating timely and best possible treatment of this disease. Pregnancy is an example of Virchow's triad: hypercoagulability, venous stasis, and vascular damage; together these factors lead to an increased incidence of venous thromboembolism. This disorder is often suspected in pregnant women because some of the physiological changes of pregnancy mimic its signs and symptoms. Despite concerns for fetal teratogenicity and oncogenicity associated with diagnostic testing, and potential adverse effects of pharmacological treatment, an accurate diagnosis of PE and a timely therapeutic intervention are crucial. Appropriate prophylaxis should be weighed against the risk of complications and offered according to risk stratification.
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Affiliation(s)
- Ghada Bourjeily
- Department of Medicine, The Warren Alpert Medical School of Brown University, Women and Infants Hospital of Rhode Island, Providence, RI 02905, USA.
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Computed Tomography in Pregnant Patients. J Med Imaging Radiat Sci 2009; 40:100-104. [DOI: 10.1016/j.jmir.2009.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 06/16/2009] [Accepted: 06/19/2009] [Indexed: 11/23/2022]
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Pahade JK, Litmanovich D, Pedrosa I, Romero J, Bankier AA, Boiselle PM. Imaging Pregnant Patients with Suspected Pulmonary Embolism: What the Radiologist Needs to Know. Radiographics 2009; 29:639-54. [DOI: 10.1148/rg.293085226] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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BJR review of the year — 2008. Br J Radiol 2009; 82:180-2. [DOI: 10.1259/bjr/22668077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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