Role of CT Pulmonary Angiography. Pulmonary Vein Mapping Trachea/Airway Lifespan, Rhode Island’s first health system, is a comprehensive, integrated, academic health system affiliated with The Warren Alpert Medical School of Brown University. The PE Graduated D-dimer (PEGeD) Study . How Much Dose Can Be Saved in Three-Phase CT Urography? A pulmonary CTA protocol optimized for pregnancy significantly improved image quality by increasing pulmonary arterial opacification, improving diagnostic adequacy, and decreasing transient interruption of the contrast bolus by unopacified blood from the IVC. When lung scintigraphy is not available or is contraindicated, an optimized pulmonary CTA protocol should be used. Three of 11 CTA studies judged to have transient interruption of the contrast bolus in group A were considered of diagnostic quality at the time of image acquisition and by subjective image quality evaluation, but the mean pulmonary arterial enhancement was classified as poor in two and as adequate in one of these studies. Three of 11 CTA studies judged to have transient interruption of the contrast bolus in group A were considered of diagnostic quality at the time of image acquisition and by subjective image quality evaluation, but the mean pulmonary arterial enhancement was classified as poor in two and as adequate in one of these studies. All reported studies used a contrast medium injection rate of 4 mL/s. When a portion of a pulmonary artery was noted to be lower in attenuation than adjacent areas of increased attenuation proximally and distally (Fig. However, the differences between the two groups in mean pulmonary arterial opacification and in the presence of transient interruption of the contrast bolus by unopacified blood from the IVC were statistically significant despite the fact that there were fewer patients in group B. AJR 2011; 197:1058-1063. Two other patients underwent lung scintigraphy after an initial nondiagnostic CTA. A region of-interest measurement may be helpful if the attenuation is greater than 78 HU. This difference achieved statistical significance (p = 0.03) because three patients in group A had repeat CTA studies. CT angiography of the chest (CTA chest) is a cross-sectional diagnostic examination that can be performed ECG-gated or non-ECG gated. 2). When a portion of a pulmonary artery was noted to be lower in attenuation than adjacent areas of increased attenuation proximally and distally (Fig. KIVC values range from 0 to 1.0; a high KIVC (> 0.8) indicates a larger contribution from the IVC to the right heart relative to the SVC and suggests the presence of transient interruption of the contrast bolus by unopacified blood from the IVC, whereas healthy control subjects have average KIVC values of approximately 0.5 [17]. Contrasted CT-angiography of the chest, often called a "PE protocol CT," has dramatically improved the diagnosis of pulmonary embolism. The inadequate group comprised CTA studies with poor pulmonary arterial enhancement, substantial noise, or substantial motion artifact. Pulmonary CT Angiography as First-Line Imaging for PE: Image Quality and Radiation Dose Considerations. According to radiology reports, 18 of 28 pulmonary CTA studies (64%) were of diagnostic quality in group A and 18 of 20 pulmonary CTA studies (90%) were of diagnostic quality in group B (p = 0.05). Split-Bolus MDCT Urography with Synchronous Nephrographic and Excretory Phase Enhancement, Review. • An empiric timing protocol for CT pulmonary angiography had lower radiation exposure compared to a timing bolus protocol. Although this difference was not statistically significant, the slightly lower radiation dose in group B may have been due to shallow inspiration and resultant decreased z-axis coverage. View Article PubMed/NCBI Google Scholar 16. Pulmonary angiography is considered the gold standard for the diagnosis of PE, although recent evidence does not necessarily always support that. The relative contribution of the IVC to the right heart was then evaluated. Evaluation of subjective image quality involved categorizing a study as either adequate or inadequate on the basis of one’s ability to diagnose PE, the adequacy of pulmonary arterial opacification, and the presence or absence of significant motion artifact and image noise. Concern exists regarding the image quality of pulmonary CTA in pregnant patients [4–7]. Comparison was made between the smart prep protocol (SPP) and the test bolus protocol (TBP) for opacification in the pulmonary trunk. In group A, final diagnoses included pneumonia (n = 2), pleural effusion (n = 1), pneumothorax (n = 1), and PE (n = 1). To retrospectively compare semi-qualitative and quantitative CT pulmonary angiography (CTPAs) image metrics testing diagnostic performance between protocols performed by 20 or 40 ml of contrast medium (CM) in patients with suspected pulmonary embolism (PE). Attenuation measurements in Hounsfield units were made at the lower superior vena cava (SVC), upper IVC, right atrium (RA), and right ventricle (RV). adequate enhancement of … When used in conjunction with validated clinical decision tools like modified Wells criteria, CT-angiography is highly sensitive (good at detecting PE when it's there and ruling it out when it's not) and specific (generating few false-positive results). The specifics will vary depending on CT hardware and software, radiologists' and referrers' preferences, institutional protocols, patient factors (e.g. 1,2 Since the 1990s, CT pulmonary angiography (CTPA) has become the method of choice for imaging in suspected PE. When the threshold of attenuation in the MPA was reached, the patient was instructed to perform shallow held inspiration, after adequate coaching by a technologist encouraging a shallow breath and the avoidance of a Valsalva maneuver. It is a preferred choice of imaging in the diagnosis of PE due to its minimally invasive nature for the patient, whose only requirement for the scan is an intravenous line. Vessel opacification was provided by IV injection of 75 mL of iopamidol (Niopam 370, Bracco) via the antecubital vein. CTA of the pulmonary arteries was performed on 200 patients with suspected pulmonary … Lung scintigraphy is not susceptible to the hemodynamic effects of pregnancy and remains a reliable tool for excluding PE in patients with normal findings on chest radiography while additionally conferring a lower maternal radiation dose than pulmonary CTA [12, 13]. CT Angiography of the Upper Extremity Arterial System: Part 1—Anatomy, Technique, and Use in Trauma Patients, Original Research. This difference achieved statistical significance (p = 0.03) because three patients in group A had repeat CTA studies. Imaging Pulmonary Infection: Classic Signs and Patterns, Review. To compare intravenous contrast material (CM) injection protocols for dual-energy CT pulmonary angiography (CTPA) in patients with suspected acute pulmonary embolism with regard to image quality and pulmonary perfused blood volume (PBV) values. The CT Coronary Angiogram is a simple procedure without any pain and anxiety . During bolus tracking, the patient was instructed to breathe quietly. This increase in blood volume is thought to contribute to hemodilution of contrast material administered to pregnant patients [5]. The first patient’s pulmonary CTA study showed adequate MPA opacification excluding a central PE, but subsegmental arterial opacification was poor. Studies analyzing pulmonary CTA of pregnant patients have confirmed that pulmonary arterial opacification is reduced during pregnancy [4, 7, 19, 20] and that transient interruption of the contrast bolus by unopacified blood from the IVC may occur more often in pregnant patients than in the general population [7]. 1,2 Since the 1990s, CT pulmonary angiography (CTPA) has become the method of choice for imaging in suspected PE. In particular, there was no reported contrast medium extravasation secondary to the higher contrast medium injection rate used in group B. We instituted a new, simple CT pulmonary angiography (CTPA) contrast material timing protocol using a standard empiric delay to replace our previous timing bolus method. European Respiratory Journal Sep 2012, 40 (Suppl 56) P1499; Share This Article: Copy. In pregnant patients with suspected PE, a pulmonary CTA protocol optimized for use in pregnancy that includes a high flow rate, a high volume, and high concentration of contrast medium and shallow held inspiration significantly increases the rate of diagnostic adequacy and pulmonary arterial opacification and decreases the incidence of transient interruption of the contrast bolus by unopacified blood from the IVC. The aim of this study was to analyze the dose reduction and image quality achieved by using 80 kV instead of 100 kV in CT pulmonary angiography protocols. The remaining 17 patients had normal radiologic findings. exercise was to investigate if a change in CT pulmonary angiography (CTPA) scanning protocol resulted in improved opacification of the pulmonary arteries. The adequate group included CTA studies with good pulmonary arterial enhancement and without significant noise or motion artifact. 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