Andrea Veltri

Accuracy of Point-of-Care Multiorgan Ultrasonography for the Diagnosis of Pulmonary Embolism

BACKGROUND Presenting signs and symptoms of pulmonary embolism (PE) are nonspecific, favoring a large use of second-line diagnostic tests such as multidetector CT pulmonary angiography (MCTPA), thus exposing patients to high-dose radiation and to potential serious complications. We investigated the diagnostic performance of multiorgan ultrasonography (lung, heart, and leg vein ultrasonography) and whether multiorgan ultrasonography combined to Wells score and D-dimer could safely reduce MCTPA tests. METHODS Consecutive adult patients suspected of PE and with a Wells score > 4 or a positive D-dimer result were prospectively enrolled in three EDs. Final diagnosis was obtained with MCTPA. Multiorgan ultrasonography was performed before MCTPA and considered diagnostic for PE if one or more subpleural infarcts, right ventricular dilatation, or DVT was detected. If multiorgan ultrasonography was negative for PE, an alternative ultrasonography diagnosis was sought. Accuracies of each single-organ and multiorgan ultrasonography were calculated. RESULTS PE was diagnosed in 110 of 357 enrolled patients (30.8%). Multiorgan ultrasonography yielded a sensitivity of 90% and a specificity of 86.2%, lung ultrasonography 60.9% and 95.9%, heart ultrasonography 32.7% and 90.9%, and vein ultrasonography 52.7% and 97.6%, respectively. Among the 132 patients (37%) with multiorgan ultrasonography negative for PE plus an alternative ultrasonographic diagnosis or plus a negative D-dimer result, no patients received PE as a final diagnosis. CONCLUSIONS Multiorgan ultrasonography is more sensitive than single-organ ultrasonography, increases the accuracy of clinical pretest probability estimation in patients with suspected PE, and may safely reduce the MCTPA burden. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT01635257; URL: www.clinicaltrials.gov.

Clinical Implications and Added Costs of Incidental Findings in an Early Detection Study of Lung Cancer by Using Low-Dose Spiral Computed Tomography

INTRODUCTION To prospectively evaluate the frequency and spectrum of incidental findings (IF) in a 5-year lung cancer screening program with low-dose spiral computed tomography (CT) and to estimate the additional costs of their imaging workup incurred from subsequent radiologic follow-up evaluation. MATERIALS AND METHODS A total of 519 asymptomatic volunteers were enrolled. All IFs were reported and were considered clinically relevant if they required further evaluations or with clinical implications if they required more than one additional diagnostic test for characterization or medical and/or surgical intervention. RESULTS IFs were commonly found (59.2%, 307/519 participants at baseline and 5.3% per year at 5-year follow-up [123 participants of 2341 LDsCT exams performed during follow-up], with an overall rate of 26.3%). IFs were categorized as previously unknown clinically relevant in 52 (10.0%) individuals at baseline. Of these, 36 (6.9%) individuals had IFs with clinical implications (10 clinically relevant, of which 6 had clinical implications, detected during the subsequent 5-year follow-up). The most common recommendations were for additional imaging of the thyroid and kidneys. Additional imaging was mainly performed by ultrasound (43/68 [63.2%]). Subsequent surgical intervention resulted from these findings in 7 (1.5%) subjects. Six malignancies were diagnosed (rate, 0.2% per year). Costs of subsequent radiologic follow-up studies were calculated as €4644.56 [U.S.

Clinical application of lung ultrasound in patients with acute dyspnoea: differential diagnosis between cardiogenic and pulmonary causes

6575.04] at baseline and €1052.30 [U.S.

Chemical shift and diffusion-weighted magnetic resonance imaging of the anterior mediastinum in oncology: Current clinical applications in qualitative and quantitative assessment

1489.69] at 5-year follow-up (average added costs per participant €8.95 [U.S.

Diffusion-weighted quantitative MRI to diagnose benign conditions from malignancies of the anterior mediastinum: Improvement of diagnostic accuracy by comparing perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient.

12.67] and €2.25 [U.S.

Comparison of CT and chemical-shift MRI for differentiating thymoma from non-thymomatous conditions in myasthenia gravis: value of qualitative and quantitative assessment.

3.19], respectively). CONCLUSIONS Low-dose spiral CT commonly detects IFs. Some of these require further investigations to assess their clinical relevance. Although such IFs add little clinical benefit to the screening intervention, moderate incremental costs are incurred based on additional radiologic procedures generated during short-term follow-up, given the potential for positive effects on patient care.

Diffusion‑weighted MRI in a case of nonsuppressing rebound thymic hyperplasia on chemical‑shift MRI

This review discusses the usefulness of bedside lung ultrasound in the diagnostic distinction between the various causes of acute dyspnoea in the emergency department, with special attention to the differential diagnosis of pulmonary oedema and exacerbation of chronic obstructive pulmonary disease (COPD). This is made possible by using mid- to low-end scanners and simple acquisition techniques accessible to both radiologists and clinicians. Major advantages include ready availability at the bedside, the absence of ionising radiation, high reproducibility and cost efficiency. The technique is based on the recognition and analysis of sonographic artefacts rather than direct visualisation of the pulmonary structures. These artefacts are caused by the interaction of water-rich structures and air, called comet tails or B-lines. When such artefacts are widely detected on anterolateral transthoracic lung scans, diffuse alveolar-interstitial syndrome can be diagnosed, which is often a sign of acute pulmonary oedema. This condition rules out exacerbation of COPD as the main cause of acute dyspnoea.RiassuntoIn questo lavoro viene discussa l’utilità dell’ecografia polmonare nella diagnosi delle diverse cause di dispnea acuta in emergenza, in particolare focalizzando l’attenzione sulla diagnosi differenziale tra l’edema polmonare e la riacutizzazione della broncopneumopatia cronica ostruttiva (BPCO). Questo è possibile utilizzando anche ecografi di fascia medio-bassa ed avvalendosi di tecniche di facile acquisizione da parte sia dei radiologi che dei clinici. I maggiori vantaggi dell’ecografia includono la sua pronta disponibilità al letto del malato, l’assenza di radiazioni ionizzanti, la riproducibilità ed i costi ridotti. La tecnica è basata sul riconoscimento e l’analisi di alcuni artefatti invece che sulla visualizzazione diretta delle strutture polmonari. Questi artefatti sono causati dalla presenza di strutture ricche di acqua ed aria, e sono chiamati “code di cometa” o linee B. Quando tali artefatti sono diffusamente visualizzati nelle scansioni trans-toraciche antero-laterali, è possibile diagnosticare la sindrome alveolo-interstiziale diffusa, che è spesso un segno di edema polmonare acuto. Questa condizione esclude la riacutizzazione di BPCO quale causa di dispnea acuta.

Diffusion-weighted quantitative MRI of pleural abnormalities: Intra- and interobserver variability in the apparent diffusion coefficient measurements.

Recently, the use of magnetic resonance (MR) in clinical practice for the evaluation of the anterior mediastinum has considerably increased due to technological improvements and standardization of thoracic protocols. Currently, MR imaging is increasingly seen as a useful problem-solving modality, especially in equivocal cases at computed tomography, with the advantage of a higher contrast resolution and no radiation exposure. Chemical shift and diffusion-weighted MR are helpful in tissue characterization and present advantages over conventional MR imaging, first in providing quantitative data, without the need for the administration of contrast medium. By detecting microscopic fat in tissue, chemical shift imaging is useful for differentiating normal thymus and rebound hyperplasia from cancer tissue at diagnosis and after chemotherapy in oncologic patients, and for distinguishing lymphoid hyperplasia from thymoma in autoimmune diseases such as myasthenia gravis. Diffusion-weighted MR reflects diffusivity of water molecules within tissue and is increasingly used as a cancer biomarker, even in the thorax, for the detection and characterization of tumors, for their differentiation from benign conditions, and for monitoring treatment response. In this review, based on the current literature, technical considerations about image acquisition and data analysis of chemical shift and diffusion-weighted MR are discussed along with clinical applications in the field of benign and malignant disease of the anterior mediastinum.

Importance of different region-of-interest protocols for the apparent diffusion coefficient measurement of tumors in diffusion-weighted magnetic resonance imaging.

To compare perfusion‐free to perfusion‐sensitive measurements of the apparent diffusion coefficient (ADC) to diagnose benign conditions from malignancies of the anterior mediastinum.

MRI and DW-MRI of Acute Pyelonephritis (APN)

AIM To evaluate the usefulness of computed tomography (CT) and chemical-shift magnetic resonance imaging (MRI) in patients with myasthenia gravis (MG) for differentiating thymoma (THY) from thymic lymphoid hyperplasia (TLH) and normal thymus (NT), and to determine which technique is more accurate. MATERIALS AND METHODS Eighty-three patients with generalised MG who underwent surgery were divided into the TLH/NT group (A; 65 patients) and THY group (B; 24 patients). Differences in qualitative characteristics and quantitative data (CT: radiodensity in Hounsfield units; MRI: signal intensity index [SII]) between groups were tested using Fishers exact test and Students t-test. Logistic regression models were estimated for both qualitative and quantitative analyses. At quantitative analysis, discrimination abilities were determined according to the area under the receiver operating characteristic (ROC) curve (AUROC) with computation of optimal cut-off points. The diagnostic accuracies of CT and MRI were compared using McNemars test. RESULTS At qualitative assessment, MRI had higher accuracy than CT (96.4%, 80/83 and 86.7%, 72/83, respectively). At quantitative analysis, both the radiodensity and SII were significantly different between groups (p<0.0001). For CT, at quantitative assessment, the AUROC of the radiodensity in discriminating between groups was 0.904 (optimal cut-off point, 20 HU) with an accuracy of 77.1% (64/83). For MRI, the AUROC of the SII was 0.989 (optimal cut-off point, 7.766%) with an accuracy of 96.4% (80/83), which was significantly higher than CT (p<0.0001). By using optimal cut-off points for cases with an erroneous diagnosis at qualitative assessment, accuracy improved both for CT (89.2%, 74/83) and MRI (97.6%, 81/83). CONCLUSION Quantitative analysis is useful in evaluating patients with MG and improves the diagnostic accuracy of CT and MRI based on qualitative assessment. Chemical-shift MRI is more reliable than CT in differentiating THYs from non-thymomatous conditions.