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Osborne D, Lattanze R, Knowland J, Bryant TE, Barvi I, Fu Y, Kiser JW. The Scientific and Clinical Case for Reviewing Diagnostic Radiopharmaceutical Extravasation Long-Standing Assumptions. Front Med (Lausanne) 2021; 8:684157. [PMID: 34262915 PMCID: PMC8273265 DOI: 10.3389/fmed.2021.684157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 06/02/2021] [Indexed: 11/13/2022] Open
Abstract
Background: The patient benefit from a diagnostic nuclear medicine procedure far outweighs the associated radiation risk. This benefit/risk ratio assumes a properly administered radiopharmaceutical. However, a significant diagnostic radiopharmaceutical extravasation can confound the procedure in many ways. We identified three current extravasation hypotheses espoused by medical societies, advisory committees, and hundreds of individual members of the nuclear medicine community: diagnostic extravasations do not cause harm, do not result in high absorbed dose to tissue, and require complex dosimetry methods that are not readily available in nuclear medicine centers. We tested these hypotheses against a framework of current knowledge, recent developments, and original research. We conducted a literature review, searched regulatory databases, examined five clinical cases of extravasated patients, and performed dosimetry on those extravasations to test these globally accepted hypotheses. Results: A literature review found 58 peer-reviewed documents suggesting patient harm. Adverse event/vigilance report database reviews for extravasations were conducted and revealed 38 adverse events which listed diagnostic radiopharmaceutical extravasation as a factor, despite a regulatory exemption for required reporting. In our own case material, assessment of care was evaluated for five extravasated patients who underwent repeat imaging. Findings reflected results of literature review and included mis- or non-identification of lesions, underestimation of Standardized Uptake Values (SUVs) by 19-73%, classification of scans as non-diagnostic, and the need to repeat imaging with the associated additional radiation exposure, inconvenience, or delays in care. Dosimetry was performed for the same five cases of diagnostic radiopharmaceutical extravasation. Absorbed doses to 5 cm3 of tissue were between 1.1 and 8.7 Gy, and shallow dose equivalent for 10 cm2 of skin was as high as 4.2 Sv. Conclusions: Our findings suggest that significant extravasations can or have caused patient harm and can irradiate patients' tissue with doses that exceed medical event reporting limits and deterministic effect thresholds. Therefore, diagnostic radiopharmaceutical injections should be monitored, and dosimetry of extravasated tissue should be performed in certain cases where thresholds are thought to have been exceeded. Process improvement efforts should be implemented to reduce the frequency of extravasation in nuclear medicine.
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Affiliation(s)
- Dustin Osborne
- Radiology Department, University of Tennessee Graduate School of Medicine, Knoxville, TN, United States
| | | | | | | | - Iryna Barvi
- Lucerno Dynamics LLC, Cary, NC, United States
| | - Yitong Fu
- Radiology Department, University of Tennessee Graduate School of Medicine, Knoxville, TN, United States
| | - Jackson W. Kiser
- Department of Molecular Imaging, Carilion Clinic, Roanoke, VA, United States
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Parker VL, Winter MC, Whitby E, Parker WAE, Palmer JE, Tidy JA, Pacey AA, Hancock BW, Harrison RF. Computed tomography chest imaging offers no advantage over chest X-ray in the initial assessment of gestational trophoblastic neoplasia. Br J Cancer 2021; 124:1066-1071. [PMID: 33328608 PMCID: PMC7961138 DOI: 10.1038/s41416-020-01206-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 10/23/2020] [Accepted: 11/26/2020] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND The International Federation of Gynaecology and Obstetrics (FIGO) score identifies gestational trophoblastic neoplasia (GTN) patients as low- or high-risk of single-agent chemotherapy resistance (SACR). Computed tomography (CT) has greater sensitivity than chest X-ray (CXR) in detecting pulmonary metastases, but effects upon outcomes remain unclear. METHODS Five hundred and eighty-nine patients underwent both CXR and CT during GTN assessment. Treatment decisions were CXR based. The number of metastases, risk scores, and risk category using CXR versus CT were compared. CT-derived chest assessment was evaluated as impact upon treatment decision compared to patient outcome, incidence of SACR, time-to-normal human chorionic gonadotrophin hormone (TNhCG), and primary chemotherapy resistance (PCR). RESULTS Metastasis detection (p < 0.0001) and FIGO score (p = 0.001) were higher using CT versus CXR. CT would have increased FIGO score in 188 (31.9%), with 43 re-classified from low- to high-risk, of whom 23 (53.5%) received curative single-agent chemotherapy. SACR was higher when score (p = 0.044) or risk group (p < 0.0001) changed. Metastases on CXR (p = 0.019) but not CT (p = 0.088) lengthened TNhCG. Logistic regression analysis found no difference between CXR (area under the curve (AUC) = 0.63) versus CT (AUC = 0.64) in predicting PCR. CONCLUSIONS CT chest would improve the prediction of SACR, but does not influence overall treatment outcome, TNhCG, or prediction of PCR. Lower radiation doses and cost mean ongoing CXR-based assessment is recommended.
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Affiliation(s)
- Victoria L. Parker
- grid.11835.3e0000 0004 1936 9262Department of Oncology and Metabolism, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield, S10 2RX UK
| | - Matthew C. Winter
- grid.11835.3e0000 0004 1936 9262Department of Oncology and Metabolism, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield, S10 2RX UK ,grid.31410.370000 0000 9422 8284Sheffield Centre for Trophoblastic Disease, Weston Park Cancer Centre, Sheffield Teaching Hospitals NHS Foundation Trust, Whitham Road, Sheffield, S10 2SJ UK
| | - Elspeth Whitby
- grid.11835.3e0000 0004 1936 9262Department of Oncology and Metabolism, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield, S10 2RX UK
| | - William A. E. Parker
- grid.11835.3e0000 0004 1936 9262School of Medicine, The University of Sheffield, Beech Hill Road, Sheffield, S10 2RX UK
| | - Julia E. Palmer
- grid.31410.370000 0000 9422 8284Department of Gynaecological Oncology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Room H18, Glossop Road, Sheffield, S10 2JF UK
| | - John A. Tidy
- grid.31410.370000 0000 9422 8284Sheffield Centre for Trophoblastic Disease, Weston Park Cancer Centre, Sheffield Teaching Hospitals NHS Foundation Trust, Whitham Road, Sheffield, S10 2SJ UK ,grid.31410.370000 0000 9422 8284Department of Gynaecological Oncology, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Room H18, Glossop Road, Sheffield, S10 2JF UK
| | - Allan A. Pacey
- grid.11835.3e0000 0004 1936 9262Department of Oncology and Metabolism, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield, S10 2RX UK
| | - Barry W. Hancock
- grid.11835.3e0000 0004 1936 9262Department of Oncology and Metabolism, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield, S10 2RX UK
| | - Robert F. Harrison
- grid.11835.3e0000 0004 1936 9262Department of Automatic Control and Systems Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD UK
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Cohen SL, Feizullayeva C, McCandlish JA, Sanelli PC, McGinn T, Brenner B, Spyropoulos AC. Comparison of international societal guidelines for the diagnosis of suspected pulmonary embolism during pregnancy. LANCET HAEMATOLOGY 2020; 7:e247-e258. [PMID: 32109405 DOI: 10.1016/s2352-3026(19)30250-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 11/13/2019] [Accepted: 11/18/2019] [Indexed: 10/24/2022]
Abstract
Pregnancy-associated pulmonary embolism is one of the leading causes of maternal mortality. Diagnosis of pulmonary embolism in pregnancy is challenging, with symptoms of pulmonary embolism mimicking those of pregnancy. Several key components such as clinical prediction tools, risk stratification, laboratory tests, and imaging widely used for diagnosis of pulmonary embolism in the non-pregnant population show limitations for diagnosis in pregnancy. Further, because of the difficulty of studying pregnant patients, high-quality research evaluating the performance of these diagnostic components in pregnancy is scarce. Seven international medical society guidelines present clinical diagnostic pathways for evaluation of pulmonary embolism in pregnancy that show conflicting recommendations on the use of these diagnostic components. This Review assesses all key components of diagnostic clinical pathways recommended by guidelines for evaluation of pulmonary embolism in pregnancy, reviews current evidence, compares the guideline recommendations with respect to each key component, and provides our preferred diagnostic pathway. It provides the guidelines and available data needed for informed decision making to diagnose pulmonary embolism in pregnancy.
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Affiliation(s)
- Stuart L Cohen
- Imaging Clinical Effectiveness and Outcomes Research, Department of Radiology, Northwell Health, Manhasset, NY, USA; Center for Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research and Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA.
| | - Chinara Feizullayeva
- Imaging Clinical Effectiveness and Outcomes Research, Department of Radiology, Northwell Health, Manhasset, NY, USA; Center for Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research and Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - John A McCandlish
- Imaging Clinical Effectiveness and Outcomes Research, Department of Radiology, Northwell Health, Manhasset, NY, USA; Center for Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research and Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA; Georgia Institute of Technology, Atlanta, GA, USA
| | - Pina C Sanelli
- Imaging Clinical Effectiveness and Outcomes Research, Department of Radiology, Northwell Health, Manhasset, NY, USA; Center for Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research and Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Thomas McGinn
- Department of Medicine, Northwell Health, Manhasset, NY, USA; Center for Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research and Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Benjamin Brenner
- Institute of Hematology, Rambam Health Care Campus and Technion, Israel Institute of Technology, Haifa, Israel; Department of Obstetrics and Gynaecology, The First I.M. Sechenov Moscow State Medical University, Moscow, Russia
| | - Alex C Spyropoulos
- Department of Medicine, Northwell Health, Manhasset, NY, USA; Center for Health Innovations and Outcomes Research, Feinstein Institutes for Medical Research and Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
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Rate of Nondiagnostic Computerized Tomography Pulmonary Angiograms (CTPAs) Performed for the Diagnosis of Pulmonary Embolism in Pregnant and Immediately Postpartum Patients. Obstet Gynecol Int 2019; 2019:1432759. [PMID: 31049065 PMCID: PMC6458938 DOI: 10.1155/2019/1432759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 02/11/2019] [Accepted: 03/12/2019] [Indexed: 11/18/2022] Open
Abstract
Objective To evaluate the nondiagnostic rate of computed tomography pulmonary angiography (CTPA) in pregnant and postpartum patients with suspected pulmonary embolism (PE) to determine whether CTPA or ventilation-perfusion (VQ) scan should be considered first line imaging in this patient population considering their equivalent accuracy and the greater radiation exposure to proliferating breast tissue of CTPA. Methods All pregnant/postpartum female patients between 18 and 50 years of age who had CTPA within the Eastern Health Authority between November 2012 and November 2016 were included. Each scan was evaluated for nondiagnosis based on two criteria: contrast density in the main pulmonary artery, and respiratory motion artefact. If either of these criteria were not met, the scan was labelled as nondiagnostic. Results The nondiagnostic rate overall was 43% (n=83). This is similar to current literature values for rates of CTPA nondiagnosis, and comparable to the reported diagnostic quality of the reporting radiologist. This is much greater compared to rates of ventilation/perfusion nondiagnosis in comparable populations. Even in patients with normal chest radiographs, which represents the main patient group where VQ may be considered as an alternative, the nondiagnostic rate of CT is much higher. Conclusion This is the first study to attempt to identify an objective method of determining nondiagnosis in pregnant and postpartum patients undergoing a CTPA. Our results strengthen the argument that alternative imaging should be considered when investigating for PE in this population in order to protect the proliferating breast tissue, and VQ scan should be considered especially in patients with normal chest X-rays.
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The Role of Computed Tomography Scanning of the Thorax in the Initial Assessment of Gestational Trophoblastic Neoplasia. Int J Gynecol Cancer 2015; 25:1731-6. [DOI: 10.1097/igc.0000000000000534] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
ObjectiveThe aim of this study was to determine whether lesions found on computed tomography (CT) imaging of the thorax would affect FIGO (International Federation of Gynecology and Obstetrics) 2000 risk score and/or alter clinical management.MethodsThe Sheffield Trophoblastic Disease database was searched for all new patients registered for staging/scoring investigations between January 1, 2006, and June 30, 2010. The FIGO 2000 score was noted and then recalculated using information from CT scan reports. Where a change of risk score would have affected a patient’s management, the case notes were further reviewed.Results191 patients had undergone both modalities of imaging. Using standard FIGO scoring, 169 and 22 patients were noted to be at low and high risk, respectively. Using information from CT imaging, only a further 20 patients would have been reclassified as high risk. Fifteen of these “new” high-risk patients required salvage treatment with intravenous chemotherapy; all were cured.ConclusionsWith no potential advantage in terms of patient outcome and significantly increased radiation dose, there is little justification for routine CT imaging of the thorax in the initial assessment of new patients with gestational trophoblastic neoplasia.
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Nyman U, Björkdahl P, Olsson ML, Gunnarsson M, Goldman B. Low-dose radiation with 80-kVp computed tomography to diagnose pulmonary embolism: a feasibility study. Acta Radiol 2012; 53:1004-13. [PMID: 22940858 DOI: 10.1258/ar.2012.120327] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Mounting collective radiation doses from computed tomography (CT) implies an increased risk of radiation-induced cancer in exposed populations, especially in the young. PURPOSE To evaluate radiation dose and image quality at 80-kVp CT to diagnose acute pulmonary embolism (PE) compared with a previous study at 100 and 120 kVp with all other scanning parameters unchanged. MATERIAL AND METHODS A custom-made chest phantom with a 12 mg I/mL-syringe was scanned at 80/100/120 kVp to evaluate relative changes in computed tomographic dose index (CTDI(vol)), attenuation, image noise, and contrast-to-noise ratio (CNR). Fifty patients underwent 80 kVp 16-row detector CT at 100 "Quality reference" mAs. A total of 350 mg I/kg were injected to compensate for increased CNR at 80 kVp, while 300 mg I/kg had been used at 100/120 kVp. CTDI(vol), dose-length product (DLP), and estimated effective dose were evaluated including Monte Carlo simulations. Pulmonary artery attenuation and noise were measured and CNR calculated. Two radiologists evaluated subjective image quality using a four-grade scale. RESULTS Switching from 120 to 80 kVp in the phantom study decreased radiation dose by 67% while attenuation and noise increased 1.6 and 2.0 times, respectively, and CNR decreased by 16%. Switching from 120 to 80 kVp in the patient studies decreased estimated effective dose from 4.0 to 1.2 mSv (70% decrease) in median while pulmonary artery attenuation and noise roughly doubled from 332 to 653 HU and from 22 to 49 HU, respectively, resulting in similar CNR (13 vs. 12). At 80 kVp all examinations were regarded as adequate (8%) or excellent (92%). CONCLUSION Switching from 120 to 80 kVp CT without increased mAs but slightly increased iodine dose may be of special benefit to diagnose PE in younger individuals with preserved renal function where the primary aim is to minimize radiation dose and reaching levels below that of scintigraphy.
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Affiliation(s)
- Ulf Nyman
- Department of Radiology, University of Lund, Lasarettet Trelleborg, Trelleborg
| | | | - Marie-Louise Olsson
- Medical Radiation Physics, Department of Clinical Sciences, University of Lund, Skåne University Hospital, Malmö
| | - Mikael Gunnarsson
- Medical Radiation Physics, Department of Clinical Sciences, University of Lund, Skåne University Hospital, Malmö
| | - Bitte Goldman
- Department of Internal Medicine, Lasarettet Trelleborg, Trelleborg, Sweden
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Goodman TR, Amurao M. Medical Imaging Radiation Safety for the Female Patient: Rationale and Implementation. Radiographics 2012; 32:1829-37. [DOI: 10.1148/rg.326125508] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Shrinking lung syndrome in pregnancy complicated by antiphospholipid antibody syndrome. Obstet Gynecol 2011; 117:506-508. [PMID: 21252806 DOI: 10.1097/aog.0b013e318206c254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Shrinking lung syndrome is characterized by pulmonary compromise secondary to unilateral or bilateral paralysis of the diaphragm. CASE Shrinking lung syndrome was diagnosed in a patient with antiphospholipid syndrome after a cesarean delivery at 28 4/7 weeks of gestation. Signs and symptoms included unexplained right-side chest pain, dyspnea, tachypnea, and absent breath sounds at the right base of the lungs. After initiation of corticosteroids, her symptoms resolved. CONCLUSION Although seen in association with systemic lupus erythematosus, shrinking lung syndrome has not been described with antiphospholipid syndrome or during pregnancy. Diagnosis and awareness are important because treatment with moderate- to high-dose corticosteroids appears to improve the clinical outcome.
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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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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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Lombaard H, Soma-Pillay P, Farrell EM. Managing acute collapse in pregnant women. Best Pract Res Clin Obstet Gynaecol 2009; 23:339-55. [DOI: 10.1016/j.bpobgyn.2009.01.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2008] [Revised: 12/23/2008] [Accepted: 01/14/2009] [Indexed: 10/21/2022]
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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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Schaefer-Prokop C, Prokop M. CTPA for the diagnosis of acute pulmonary embolism during pregnancy. Eur Radiol 2008; 18:2705-8. [PMID: 18795302 DOI: 10.1007/s00330-008-1158-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Accepted: 08/05/2008] [Indexed: 10/21/2022]
Abstract
CT pulmonary angiography (CTPA) has been suggested by the Fleischner society as the first test following a negative leg ultrasound in pregnant patients with suspected pulmonary embolism. This editorial discusses the use of CTPA as a diagnostic tool in pregnant women and comments on the need for specifically adapting CT protocols during pregnancy in the light of new research describing a substantial number of non-diagnostic examinations in pregnant women if routine scanning protocols are used for CTA of the pulmonary arteries. Potential reasons for these high numbers of insufficient examinations are physiological changes occurring during pregnancy that lead to a hyperdynamic circulation, which reduces average enhancement of the pulmonary vasculature. In addition, there are possible breathing-related effects that include an increased risk for Valsalva manoeuvre with devastating effects for pulmonary vascular enhancement. Techniques to overcome these problems are discussed: bolus triggering with short start delays, high flow rates or high contrast medium concentration, preferential use of fast CT systems and the use of low kVp CT techniques. CT data acquisition during deep inspiration should be avoided and shallow respiration may be considered as an alternative to suspended breathing in this patient group. All these factors can contribute to optimization of the quality of pulmonary CTA in pregnant patients. It is time now to adapt our protocols and provide optimum care for this sensitive patient group.
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