Accuracy of the long-axis area-length method for the measurement of left ventricular volumes and ejection fraction using multidetector computed tomography

Multidetector computed tomography (MDCT) is useful for assessing left ventricular (LV) volumes and function. Validation has mainly been carried out using Simpson's method of summing up consecutive short-axis areas. Because the latter method is time-consuming, many users prefer using a quicker method, based on a single view or a pair of views. To evaluate the accuracy of the long-axis area-length method (AL), which has not been validated for MDCT, using Simpson's method as the gold standard, as well as right anterior oblique LV angiography as a clinical standard. Twenty-three patients admitted with acute chest pain were clinically evaluated with electrocardiogram-gated MDCT and invasive LV angiography. MDCT-based end-diastolic, end-systolic and stroke volumes, and ejection fraction (EF) were calculated using Simpson's method, biplane AL and single-plane AL. For LV angiography, EF was calculated using single-plane AL. A Bland-Altman analysis showed a close agreement between biplane AL and Simpson's method for EF, with 1% underestimation, 95% CI of ±11% and a correlation of 0.89. For end-diastolic, end-systolic and stroke volumes, overestimations of 7 mL, 4 mL and 2 mL, and 95% CI of ±27 mL, ±15 mL and ±26 mL, respectively were found. Correlation coefficients were 0.95, 0.97 and 0.82, respectively. Comparisons with LV angiography were considerably weaker. The vertical long-axis AL method by MDCT correlated better with both LV angiography and Simpson's method than the horizontal long-axis AL method. The biplane AL method gives results for EF, which correspond closely with the more cumbersome Simpson's method, although volumes are slightly overestimated. La tomographie à multidétecteurs (TGMD) est utile pour évaluer les volumes et la fonction ventriculaires gauches (VG). La validation a été pour une bonne part réalisée à l’aide de la méthode de Simpson établissant la somme des aires axe court consécutives. Parce que cette dernière méthode est fastidieuse, de nombreux utilisateurs préfèrent une méthode plus rapide basée sur une ou deux perspectives. Évaluer la précision de la méthode aire-longueur (AL) long axe, qui n’a pas été validée pour la TGMD, à l’aide de la méthode de Simpson comme étalon-or et à l’aide de l’angiographie VG droite antérieure oblique comme norme clinique. Vingt-trois patients admis pour DRS aiguë ont été évalués sur le plan clinique au moyen d’une TGMD synchronisée avec l’électrocardiogramme et d’une angiographie VG effractive. Les volumes télédiastoliques, télésystoliques, le volume d’éjection systolique et la fraction d’éjection (FÉ) ont été calculés à l’aide de la méthode de Simpson AL bidimensionnelle et AL unidimensionnelle. Pour l’angiographie VG, la FÉ a été calculée à l’aide de la méthode AL unidimensionnelle. Une analyse de Bland-Altman a montré une concordance étroite entre la méthode AL bidimensionnelle et la méthode de Simpson pour la FÉ, avec une sous-estimation de 1% et un IC à 95% de ± 11% et un coefficient de 0,89. Pour les volumes télédiastoliques, télésystoliques et d’éjection systolique, on a observé des surestimations de 7 mL, 4 mL, 2 mL, et des IC à 95% de ± 27 mL, ± 15 mL et ± 26 mL. Les coefficients de corrélation étaient de 0.95, 0.97 et 0.82, respectivement. Les comparaisons avec l’angiographie VG ont été considérablement plus faibles. La méthode AL long axe par TGMD a été en meilleure corrélation avec l’angiographie VG et avec la méthode de Simpson, comparativement à la méthode AL long axe horizontale. La méthode AL bidimensionnelle donne des résultats de FÉ qui correspondent étroitement avec la méthode de Simpson, plus fastidieuse, même si les volumes sont légèrement surestimés

Accuracy of the long-axis area-length method for the measurement of left ventricular volumes and ejection fraction using multidetector computed tomography

Multidetector computed tomography (MDCT) is useful for assessing left ventricular (LV) volumes and function. Validation has mainly been carried out using Simpson's method of summing up consecutive short-axis areas. Because the latter method is time-consuming, many users prefer using a quicker method, based on a single view or a pair of views. To evaluate the accuracy of the long-axis area-length method (AL), which has not been validated for MDCT, using Simpson's method as the gold standard, as well as right anterior oblique LV angiography as a clinical standard. Twenty-three patients admitted with acute chest pain were clinically evaluated with electrocardiogram-gated MDCT and invasive LV angiography. MDCT-based end-diastolic, end-systolic and stroke volumes, and ejection fraction (EF) were calculated using Simpson's method, biplane AL and single-plane AL. For LV angiography, EF was calculated using single-plane AL. A Bland-Altman analysis showed a close agreement between biplane AL and Simpson's method for EF, with 1% underestimation, 95% CI of ±11% and a correlation of 0.89. For end-diastolic, end-systolic and stroke volumes, overestimations of 7 mL, 4 mL and 2 mL, and 95% CI of ±27 mL, ±15 mL and ±26 mL, respectively were found. Correlation coefficients were 0.95, 0.97 and 0.82, respectively. Comparisons with LV angiography were considerably weaker. The vertical long-axis AL method by MDCT correlated better with both LV angiography and Simpson's method than the horizontal long-axis AL method. The biplane AL method gives results for EF, which correspond closely with the more cumbersome Simpson's method, although volumes are slightly overestimated. La tomographie à multidétecteurs (TGMD) est utile pour évaluer les volumes et la fonction ventriculaires gauches (VG). La validation a été pour une bonne part réalisée à l’aide de la méthode de Simpson établissant la somme des aires axe court consécutives. Parce que cette dernière méthode est fastidieuse, de nombreux utilisateurs préfèrent une méthode plus rapide basée sur une ou deux perspectives. Évaluer la précision de la méthode aire-longueur (AL) long axe, qui n’a pas été validée pour la TGMD, à l’aide de la méthode de Simpson comme étalon-or et à l’aide de l’angiographie VG droite antérieure oblique comme norme clinique. Vingt-trois patients admis pour DRS aiguë ont été évalués sur le plan clinique au moyen d’une TGMD synchronisée avec l’électrocardiogramme et d’une angiographie VG effractive. Les volumes télédiastoliques, télésystoliques, le volume d’éjection systolique et la fraction d’éjection (FÉ) ont été calculés à l’aide de la méthode de Simpson AL bidimensionnelle et AL unidimensionnelle. Pour l’angiographie VG, la FÉ a été calculée à l’aide de la méthode AL unidimensionnelle. Une analyse de Bland-Altman a montré une concordance étroite entre la méthode AL bidimensionnelle et la méthode de Simpson pour la FÉ, avec une sous-estimation de 1% et un IC à 95% de ± 11% et un coefficient de 0,89. Pour les volumes télédiastoliques, télésystoliques et d’éjection systolique, on a observé des surestimations de 7 mL, 4 mL, 2 mL, et des IC à 95% de ± 27 mL, ± 15 mL et ± 26 mL. Les coefficients de corrélation étaient de 0.95, 0.97 et 0.82, respectivement. Les comparaisons avec l’angiographie VG ont été considérablement plus faibles. La méthode AL long axe par TGMD a été en meilleure corrélation avec l’angiographie VG et avec la méthode de Simpson, comparativement à la méthode AL long axe horizontale. La méthode AL bidimensionnelle donne des résultats de FÉ qui correspondent étroitement avec la méthode de Simpson, plus fastidieuse, même si les volumes sont légèrement surestimés

Clinical evaluation of a fully automated model-based algorithm to calculate left ventricular volumes and ejection fraction using multidetector computed tomography

Objectives: To evaluate feasibility and accuracy of a fully automatic algorithm (FAA) for calculating left ventricular volumes and ejection fraction (LVEF) from multidetector computed tomography (MDCT) studies versus a previously validated method based on Simpson's method serving as our reference standard (RS), and left ventriculography (LVG), in patients with acute chest pain (ACP). Methods: 23 patients admitted with ACP underwent ECG-gated MDCT, as well as LVG during their hospitalization. MDCT based end-diastolic, end-systolic and stroke volumes (EDV, ESV, SV) and LVEF were calculated using the RS and the FAA. Results: One patient was excluded after FAA failure to detect contours. In the remaining 22 patients, mean±SD LVEF measurements were RS 61±11%, FAA 59±11% (r = 0.91 versus RS), LVG 57±16% (r = 0.6 versus RS). In comparison to RS, FAA overestimated EDV by 10.1±8.5 ml, ESV by 7.3±6.4 ml and SV by 3.6±8.6 ml, and underestimated LVEF measurements by 2.7±4.6%, related to contour smoothing. LVEF by FAA was within 8% of RS for all patients except one. In contrast, LVG differed significantly from RS. Conclusions: The evaluated FAA obtained accurate, clinically relevant results for left ventricular volumes and LVEF relative to the RS

Multimodality Image Fusion with PSMA PET/CT and High-Intensity Focused Ultrasound Focal Therapy for Primary Diagnosis and Management of Prostate Cancer: A Planned Research Initiative

Recent developments in diagnostic imaging herald a new approach to diagnosis and management of prostate cancer. Multimodality fusion that combines anatomic with functional imaging data has surpassed either of the two alone. This opens up the possibility to “find and fix” malignancy with greater accuracy than ever before. This is particularly important for prostate cancer because it is the most common male cancer in most developed countries. This article describes technical advances under investigation at our institution and others using multimodality image fusion of magnetic resonance imaging (MRI), transrectal ultrasound (TRUS), and PSMA PET/CT (defined as the combination of prostate-specific membrane antigen [PSMA], positron emission tomography [PET], and computed tomography [CT]) for personalized medicine in the diagnosis and focal therapy of prostate cancer with high-intensity focused ultrasound (HiFUS)

Cardiology consultation as a gatekeeper prior to cardiac multi-detector computed tomography scan

Multi-detector computed tomography has advanced enormously and now enables non-invasive evaluation of coronary arteries as well as cardiac anatomy, function and perfusion. However, the role of cardiac MDCT is not yet determined in the medical community and, consequently, many clinically unnecessary scans are performed solely on a self-referral basis. To prospectively evaluate the role of a cardiologist consultation and recommendation prior to the scan, and the influence on the diagnostic yield of cardiac MDCT. In our center a CT service was initiated, but with the prerequisite approval of a cardiologist before performance of the CT. Each individual who wanted and was willing to pay for a cardiac CT was interviewed by an experienced cardiologist who determined whether cardiac MDCT was the most appropriate next test in the cardiovascular evaluation. Subjects were classified into three groups: a) those with a normal or no prior stress test, no typical symptoms and no significant risk factors of coronary artery disease were recommended to perform a stress test or to remain under close clinical follow-up without MDCT; b) those with an equivocal stress test, atypical symptoms and/or significant risk factors were allowed to have cardiac MDCT; and c) those with positive stress test or clinically highly suspected CAD were advised to go directly to invasive coronary angiography. CT findings were categorized as normal CAD (normal calcium score and no narrowings), 50% CAD. A total of 254 people were interviewed, and in only 39 cases did the cardiologist approve the CT. However, 61 of the 215, despite our recommendation not to undergo CT, decided to have the scan. Assessment of the 100 cases that underwent MDCT showed a statistically significant better discrimination of significant CAD, according to the cardiologist's recommendation: MDCT not recommended in 3/54 (6%) vs. MDCT recommended in 12/39 (31%) vs. recommended invasive coronary angiography in 4/7 (57%)(P<0.001). Detection of coronary calcification, as well as MDCT angiography can provide clinically useful information if applied to suitable patient groups. It is foreseeable that MDCT angiography will become part of the routine workup in some subsets of patients with suspected CAD. Selection of patients undergoing MDCT scans by a cardiologist improves the ability of the test to stratify patients, preventing unnecessary scans in both high and low risk patients

Quantitative evaluation of regional left ventricular function by multidetector computed tomography

: Because most contemporary workstations offer quantitative analysis of regional function by multidetector computed tomography, we aimed to establish typical values for normal, hypokinetic, and akinetic regions, and to establish optimal thresholds to differentiate between normal and abnormal values. : For 33 patients, quantitative regional functional parameters were compared with visual analysis by both multidetector computed tomography and echocardiography. Normal values were established to normalize for segmental variability. Optimal thresholds were established to differentiate between normal and abnormal segments by receiver operating characteristic analysis. : Akinetic, hypokinetic, and normokinetic segments demonstrated significant differences (P < 0.0001) for end-systolic thickness (mean [95% confidence interval], 9.4 [4.5-14.3], 11.7 [7.2-16.2], and 14.3 mm [8.2-20.3 mm]), respectively; thickening, 24% [-22% to 71%], 45% [-16% to 106%], and 82% [10%-154%]), respectively; and motion, 3.5 [-2.0 to 8.9], 6.1 [-0.2 to 12.4], and 8.5 mm [1.8-15.3 mm], respectively). Thickening performed best with area under the curve of 0.87 and sensitivity equal to specificity of 82%. Intraobserver variability was good, but interobserver variability was only moderate. : Quantification of regional myocardial function can be performed to assist the physician in mapping left ventricular function

Thoraco-abdominal Aorta Dissection: Look Again Before You Leap

Aortic dissection is a life-threatening condition that might require immediate assessment and therapy. We present the case of a 71-year-old woman with essential hypertension complaining about low back pain; unenhanced thoracic-lumbar spine computed tomography examination (CT) revealed a hyperdense thin line across the aorta with an appearance of "double aortic lumen". Enhanced CT scan confirmed the diagnosis of type B aortic dissection. Radiologists should be familiar with this finding that could be considered a new radiological sign of aortic dissection on unenhanced CT examination

Assessment of Diastolic Function in Hypertrophic Cardiomyopathy by Computed Tomography-Derived Analysis of Left Ventricular Filling

Hypertrophic cardiomyopathy (HCM) is characterized by diastolic dysfunction, which is difficult to assess by noninvasive methods. We hypothesized that measurement of simultaneous left ventricular (LV) and left atrial (LA) volume changes by cardiac computed tomography would be useful in the assessment of diastolic function in HCM. We studied 21 patients with HCM and 21 age-matched controls. The LA and LV volumes were calculated and early and late diastolic volume changes derived. The HCM patients had significantly larger LA volumes and reduced LA total emptying fraction (30 ± 7% vs 42 ± 6%; P < 0.0001). Conduit volume was increased (30 ± 6 vs 22 ± 4 mL/m; P < 0.0001) and contributed a significantly higher proportion of total LV diastolic filling, suggesting that passive filling of the LV compensates for LA dysfunction, but at the expense of increased pulmonary filling pressure. This study suggests that simultaneous depiction of computed tomography-derived LV and LA volume changes can characterize diastolic dysfunction in HCM