Low Sensitivity of Admission Lung US Compared to Chest CT for Diagnosis of Lung Involvement in a Cohort of 82 Patients with COVID-19 Pneumonia.

Background and Objectives: The potential role of lung ultrasound (LUS) in characterizing lung involvement in Coronavirus disease 2019 (COVID-19) is still debated. The aim of the study was to estimate sensitivity of admission LUS for the detection of SARS-CoV-2 lung involvement using Chest-CT (Computed Tomography) as reference standard in order to assess LUS usefulness in ruling out COVID-19 pneumonia in the Emergency Department (ED). Methods: Eighty-two patients with confirmed COVID-19 and signs of lung involvement on Chest-CT were consecutively admitted to our hospital and recruited in the study. Chest-CT and LUS examination were concurrently performed within the first 6-12h from admission. Sensitivity of LUS was calculated using CT findings as a reference standard. Results: Global LUS sensitivity in detecting COVID-19 pulmonary lesions was 52%. LUS sensitivity ranged from 8% in case of focal and sporadic ground-glass opacities (mild disease), to 52% for a crazy-paving pattern (moderate disease) and up to 100% in case of extensive subpleural consolidations (severe disease), although LUS was not always able to detect all the consolidations assessed at Chest-CT. LUS sensitivity was higher in detecting a typical Chest-CT pattern (60%) and abnormalities showing a middle-lower zone predominance (79%). Conclusions: As admission LUS may result falsely negative in most cases, it should not be considered as a reliable imaging tool in ruling out COVID-19 pneumonia in patients presenting in ED. It may at least represent an expanded clinical evaluation that needs integration with other diagnostic tests (e.g., nasopharyngeal swab, Chest-CT).

Assessment of bone marrow fat by 3-Tesla magnetic resonance spectroscopy in patients with chronic kidney disease.

Background: Proton magnetic resonance spectroscopy (1H MRS) is an imaging method for quantification of bone marrow fat. It has been used for evaluation of bone marrow changes in patients with chronic disorders, such as chronic kidney disease (CKD). In these patients, there is a high turnover state, with an excessive amount of non-mineralized component of bone, leading to skeletal fragility and subsequent increased fracture risk. Methods: Thirty CKD patients underwent magnetic resonance spectroscopy (MRS) and quantitative computed tomography (QCT), and eight healthy controls underwent MRS at lumbar spine. Proton density fat fraction (PDFF) and volumetric bone mineral density (vBMD) of L1-L3 were determined from MRS and QCT respectively. CKD patients were divided into three groups according to glomerular filtration rate (GFR); for each patient, blood levels of parathyroid hormone (PTH) were also reported. Paired t-tests, Pearson's correlation coefficients and analysis of variance were applied. Results: The mean age of patients was 59.6±11.5 years, mean GFR value was 21.5±8.8 mL/min and mean PTH value was 149.2±53.1 pg/mL. PDFF at L1-L3 levels was significantly higher in CKD patients compared to controls (71.4±8.7 vs. 55.5±7.6; P<0.001) and showed an inverse correlation with vBMD (r=-0.71; P<0.001). PDFF significantly increased from CKD group 1 to CKD group 3 (P=0.002) and was inversely correlated with GFR (r=-0.53; P=0.003). There was no significant association between PDFF and PTH values (P>0.05). Conclusions: In CKD patients, PDFF assessed by MRS at lumbar spine is higher than in healthy population, correlates with bone loss assessed by QCT and significantly increases with the worsening of renal function. MRS is a reliable and highly repeatable tool for PDFF quantification in CKD patients.

Contrast-Enhanced Ultrasound in Distinguishing between Malignant and Benign Peripheral Pulmonary Consolidations: The Debated Utility of the Contrast Enhancement Arrival Time.

Background. Limited studies and observations conducted on a too small number of patients prevent determining the actual clinical utility of pulmonary contrast-enhanced ultrasound (CEUS). The aim of the present study was to examine the efficacy of contrast enhancement (CE) arrival time (AT) and other dynamic CEUS findings for differentiating between malignant and benign peripheral lung lesions. Methods. 317 inpatients and outpatients (215 men, 102 women; mean age: 52 years) with peripheral pulmonary lesions were included in the study and underwent pulmonary CEUS. Patients were examined in a sitting position after receiving an intravenous injection of 4.8 mL of sulfur hexafluoride microbubbles stabilized by a phospholipid shell as ultrasound contrast agent (SonoVue-Bracco; Milan, Italy). Each lesion was observed for at least 5 min in real-time and the following temporal characteristics of enhancement were detected: the arrival time (AT) of microbubbles in the target lesion; the enhancement pattern; the wash-out time (WOT) of microbubbles. Results were then compared in light of the definitive diagnosis of community acquired pneumonia (CAP) or malignancies, which was not known at the time of CEUS examination. All malignant cases were diagnosed by histological results, while pneumonia was diagnosed on the basis of clinical and radiological follow-up, laboratory findings and, in some cases, histology. Results. CE AT has not been shown to differ between benign and malignant peripheral pulmonary lesions. The overall diagnostic accuracy and sensibility of a CE AT cut-off value < 10 s in discriminating benign lesions were low (diagnostic accuracy: 47.6%; sensibility: 5.3%). Poor results were also obtained in the sub-analysis of small (mean diameter < 3 cm) and large (mean diameter > 3 cm) lesions. No differences were recorded in the type of CE pattern showed between benign and malignant peripheral pulmonary lesions. In benign lesions we observed a higher frequency of delayed CE wash-out time (WOT) > 300 s. Anyhow, a CE WOT cut-off value > 300 s showed low diagnostic accuracy (53.6%) and sensibility (16.5%) in discriminating between pneumonias and malignancies. Similar results were also obtained in the sub-analysis by lesion size. Squamous cell carcinomas showed a more delayed CE AT compared to other histopathology subtypes. However, such a difference was statistically significant with undifferentiated lung carcinomas. Conclusions. Due to an overlap of CEUS timings and patterns, dynamic CEUS parameters cannot effectively differentiate between benign and malignant peripheral pulmonary lesions. Chest CT remains the gold standard for lesion characterization and the eventual identification of other pneumonic non-subpleural localizations. Furthermore, in the case of malignancy, a chest CT is always needed for staging purposes.

Thoracic ultrasound combined with low-dose computed tomography may represent useful screening strategy in highly exposed population in the industrial city of Taranto (Italy).

Objectives: We validated a screening protocol in which thoracic ultrasound (TUS) acts as a first-line complementary imaging technique in selecting patients which may deserve a second-line low-dose high resolution computed tomography (HRCT) scan among a population of asymptomatic high-risk subjects for interstitial lung abnormalities (ILA) and lung cancer. Due to heavy environmental pollution burden, the district Tamburi of Taranto has been chosen as "case study" for this purpose. Methods: From July 2018 to October 2020, 677 patients aged between 45 and 65 year and who had been living in the Tamburi district of Taranto for at least 10 years were included in the study. After demographic, clinical and risk factor exposition data were collected, each participant underwent a complete TUS examination. These subjects were then asked to know if they agreed to perform a second-level examination by low-dose HRCT scan. Results: On a total of 167 subjects (24.7%) who agreed to undergo a second-level HRCT, 85 patients (50.9%) actually showed pleuro-pulmonary abnormalities. Interstitial abnormalities were detected in a total of 36 patients on HRCT scan. In particular, 34 participants presented subpleural ILAs, that were classified in the fibrotic subtype in 7 cases. The remaining 2 patients showed non-subpleural interstitial abnormalities. Subpleural nodules were observed in 46 patients. TUS showed an overall diagnostic accuracy of 88.6% in detecting pleuro-pulmonary abnormalities in comparison with HRCT scan, with a sensitivity of 95.3%, a specificity of 81.7%, a positive predictive value of 84.4% and a negative predictive value of 94.4%. The matched evaluation of specific pulmonary abnormalities on HRTC scan (i.e., interstitial abnormalities or pulmonary nodules) with determinate sonographic findings revealed a reduction in both TUS sensibility and specificity. Focusing TUS evaluation on the assessment of interstitial abnormalities, a thickened pleural line showed a sensitivity of 63.9% and a specificity of 69.5%, hypoechoic striae showed a sensitivity of 38.9% and a specificity of 90.1% and subpleural nodules showed a sensitivity of 58.3% and a specificity of 77.1%. Regarding to the assessment of subpleural nodules, TUS showed a sensitivity of 60.9% and a specificity of 81.0%. However, the combined employment of TUS examination and HRCT scans allowed to identify 34 patients with early subpleural ILA and to detect three suspicious pulmonary nodules (of which two were intraparenchymal and one was a large subpleural mass), which revealed to be lung cancers on further investigations. Conclusion: A first-line TUS examination might aid the identification of subjects highly exposed to environmental pollution, who could benefit of a second-line low-dose HRCT scan to find early interstitial lung diseases as well as lung cancer. Protocol registration code: PLEURO-SCREENING-V1.0_15 Feb, 17.

CT-Guided Transthoracic Biopsy of Pulmonary Lesions: Diagnostic versus Nondiagnostic Results.

(1) Background: Despite the high accuracy of CT-guided transthoracic biopsy for diagnosis of pulmonary lesions, in a certain amount of cases biopsy results may indicate the presence of nonspecific findings or insufficient material. We aimed to investigate the effectiveness of CT-guided transthoracic biopsy of pulmonary lesions in providing a specific diagnosis and to analyze the variables affecting biopsy results. (2) Methods: In this retrospective study, a total of 170 patients undergoing 183 CT-guided transthoracic biopsies of pulmonary lesions were included. The clinical, radiological and pathological data were reviewed to classify biopsy results as diagnostic or nondiagnostic and to identify which variables were associated with the two groups. (3) Results: The biopsy results were diagnostic in 150 cases (82.0%), of which 131 (87.3%) positive for malignancy and 19 (12.7%) with specific benign lesions, and nondiagnostic in 33 cases (18.0%). Twenty-two of the thirty-three (66.7%) nondiagnostic cases were finally determined as malignancies and eleven (33.3%) as benign lesions. In the diagnostic group, all the 131 biopsies positive for malignancy were confirmed to be malignant at final diagnosis (87.3%); of 19 biopsies with specific benign lesions, 13 cases were confirmed to be benign (8.7%), whereas six cases had a final diagnosis of malignancy (4%). Multivariate analysis showed increased risk of nondiagnostic biopsy for lesions ≤ 20 mm (p = 0.006) and lesions with final diagnosis of benignity (p = 0.001). (4) Conclusions: CT-guided transthoracic lung biopsy is an effective technique for the specific diagnosis of pulmonary lesions, with a relatively acceptable proportion of nondiagnostic cases. Small lesion size and final benign diagnosis are risk factors for nondiagnostic biopsy results.

Pulmonary Artery Stump Thrombosis: To Treat or Not to Treat? The Question Is Still Open. Description of a Case and Review of the Literature.

Pulmonary artery stump thrombosis (PAST) represents a possible complication after lung surgery. We report the case of a 59-year-old man who presented with dyspnoea about 4 years after right pneumonectomy due to squamous cell lung cancer. A CT-scan showed the presence of pulmonary artery stump thrombosis. Although there was no evidence of pulmonary embolism, given the clinical features and radiological shape of the thrombus, anticoagulation treatment with low-molecular-weight heparin was started with improvement of symptoms. The patient was discharged on anticoagulant treatment and a pulmonary CT-scan performed 4 months later showed an almost complete resolution of the PAST. Pathophysiological mechanisms of PAST are still unknown, although several hypotheses have been proposed. However, the decision to treat PAST with anticoagulants is still controversial. A review of literature will be provided in order to discuss risk factors, possible etiologies and to highlight clinical and radiological characteristics that could suggest to treat this condition, in particular when there is an increased risk of complications.

Transthoracic Ultrasound in Infectious Organizing Pneumonia: A Useful Guide for Percutaneous Needle Biopsy.

In patients presenting with classical features of CAP (i.e., new peripheral pulmonary consolidations and symptoms including fever, cough, and dyspnea), a clinical response to the appropriate therapy occurs in few days. When clinical improvement has not occurred and chest imaging findings are unchanged or worse, a more aggressive approach is needed in order to exclude other non-infective lesions (including neoplasms). International guidelines do not currently recommend the use of transthoracic ultrasound (TUS) as an alternative to chest X-ray (CXR) or chest computed tomography (CT) scan for the diagnosis of CAP. However, a fundamental role for TUS has been established as a guide for percutaneous needle biopsy (US-PNB) in pleural and subpleural lesions. In this retrospective study, we included 36 consecutive patients whose final diagnosis, made by a US-guided percutaneous needle biopsy (US-PTNB), was infectious organizing pneumonia (OP). Infective etiology was confirmed by additional information from microbiological and cultural studies or with a clinical follow-up of 6-12 months after a second-line antibiotic therapy plus corticosteroids. All patients have been subjected to a chest CT and a systematic TUS examination before biopsy. This gave us the opportunity to explore TUS performance in assessing CT findings of infective OP. TUS sensitivity and specificity in detecting air bronchogram and necrotic areas were far lower than those of CT scan. Conversely, TUS showed superiority in the detection of pleural effusion. Although ultrasound findings did not allow the characterization of chronic subpleural lesions, TUS confirmed to be a valid diagnostic aid for guiding percutaneous needle biopsy of subpleural consolidations.

Lung Ultrasound in the Diagnosis of COVID-19 Pneumonia: Not Always and Not Only What Is COVID-19 "Glitters".

Background: In the current coronavirus disease-2019 (COVID-19) pandemic, lung ultrasound (LUS) has been extensively employed to evaluate lung involvement and proposed as a useful screening tool for early diagnosis in the emergency department (ED), prehospitalization triage, and treatment monitoring of COVID-19 pneumonia. However, the actual effectiveness of LUS in characterizing lung involvement in COVID-19 is still unclear. Our aim was to evaluate LUS diagnostic performance in assessing or ruling out COVID-19 pneumonia when compared with chest CT (gold standard) in a population of SARS-CoV-2-infected patients. Methods: A total of 260 consecutive RT-PCR confirmed SARS-CoV-2-infected patients were included in the study. All the patients underwent both chest CT scan and concurrent LUS at admission, within the first 6-12 h of hospital stay. Results: Chest CT scan was considered positive when showing a "typical" or "indeterminate" pattern for COVID-19, according to the RSNA classification system. Disease prevalence for COVID-19 pneumonia was 90.77%. LUS demonstrated a sensitivity of 56.78% in detecting lung alteration. The concordance rate for the assessment of abnormalities by both methods increased in the case of peripheral distribution and middle-lower lung location of lesions and in cases of more severe lung involvement. A total of nine patients had a "false-positive" LUS examination. Alternative diagnosis included chronic heart disease (six cases), bronchiectasis (two cases), and subpleural emphysema (one case). LUS specificity was 62.50%. Collateral findings indicative of overlapping conditions at chest CT were recorded also in patients with COVID-19 pneumonia and appeared distributed with increasing frequency passing from the group with mild disease (17 cases) to that with severe disease (40 cases). Conclusions: LUS does not seem to be an adequate tool for screening purposes in the ED, due to the risk of missing some lesions and/or to underestimate the actual extent of the disease. Furthermore, the not specificity of LUS implies the possibility to erroneously classify pre-existing or overlapping conditions as COVID-19 pneumonia. It seems more safe to integrate a positive LUS examination with clinical, epidemiological, laboratory, and radiologic findings to suggest a "virosis." Viral testing confirmation is always required.

Diagnosis of COVID-19 in Patients with Negative Nasopharyngeal Swabs: Reliability of Radiological and Clinical Diagnosis and Accuracy Versus Serology.

BACKGROUND: The diagnosis of Coronavirus disease 2019 (COVID-19) relies on the positivity of nasopharyngeal swab. However, a significant percentage of symptomatic patients may test negative. We evaluated the reliability of COVID-19 diagnosis made by radiologists and clinicians and its accuracy versus serology in a sample of patients hospitalized for suspected COVID-19 with multiple negative swabs. METHODS: Admission chest CT-scans and clinical records of swab-negative patients, treated according to the COVID-19 protocol or deceased during hospitalization, were retrospectively evaluated by two radiologists and two clinicians, respectively. RESULTS: Of 254 patients, 169 swab-confirmed cases and one patient without chest CT-scan were excluded. A total of 84 patients were eligible for the reliability study. Of these, 21 patients died during hospitalization; the remaining 63 underwent serological testing and were eligible for the accuracy evaluation. Of the 63, 26 patients showed anti-Sars-Cov-2 antibodies, while 37 did not. The inter-rater agreement was "substantial" (kappa 0.683) between radiologists, "moderate" (kappa 0.454) between clinicians, and only "fair" (kappa 0.341) between radiologists and clinicians. Both radiologic and clinical evaluations showed good accuracy compared to serology. CONCLUSIONS: The radiologic and clinical diagnosis of COVID-19 for swab-negative patients proved to be sufficiently reliable and accurate to allow a diagnosis of COVID-19, which needs to be confirmed by serology and follow-up.

The correlation of background parenchymal enhancement in the contralateral breast with patient and tumor characteristics of MRI-screen detected breast cancers.

PURPOSE: Higher background parenchymal enhancement (BPE) could be used for stratification of MRI screening programs since it might be related to a higher breast cancer risk. Therefore, the purpose of this study is to correlate BPE to patient and tumor characteristics in women with unilateral MRI-screen detected breast cancer who participated in an intermediate and high risk screening program. As BPE in the affected breast may be difficult to discern from enhancing cancer, we assumed that BPE in the contralateral breast is a representative measure for BPE in women with unilateral breast cancer. MATERIALS AND METHODS: This retrospective study was approved by our local institutional board and a waiver for consent was granted. MR-examinations of women with unilateral breast cancers screen-detected on breast MRI were evaluated by two readers. BPE in the contralateral breast was rated according to BI-RADS. Univariate analyses were performed to study associations. Observer variability was computed. RESULTS: Analysis included 77 breast cancers in 76 patients (age: 48±9.8 years), including 62 invasive and 15 pure ductal carcinoma in-situ cases. A negative association between BPE and tumor grade (p≤0.016) and a positive association with progesterone status (p≤0.021) was found. The correlation was stronger when only considering invasive disease. Inter-reader agreement was substantial. CONCLUSION: Lower BPE in the contralateral breast in women with unilateral breast cancer might be associated to higher tumor grade and progesterone receptor negativity. Great care should be taken using BPE for stratification of patients to tailored screening programs.

Time to enhancement derived from ultrafast breast MRI as a novel parameter to discriminate benign from malignant breast lesions.

OBJECTIVES: To investigate time to enhancement (TTE) as novel dynamic parameter for lesion classification in breast magnetic resonance imaging (MRI). METHODS: In this retrospective study, 157 women with 195 enhancing abnormalities (99 malignant and 96 benign) were included. All patients underwent a bi-temporal MRI protocol that included ultrafast time-resolved angiography with stochastic trajectory (TWIST) acquisitions (1.0×0.9×2.5mm, temporal resolution 4.32s), during the inflow of contrast agent. TTE derived from TWIST series and relative enhancement versus time curve type derived from volumetric interpolated breath-hold examination (VIBE) series were assessed and combined with basic morphological information to differentiate benign from malignant lesions. Receiver operating characteristic analysis and kappa statistics were applied. RESULTS: TTE had a significantly better discriminative ability than curve type (p<0.001 and p=0.026 for reader 1 and 2, respectively). Including morphology, sensitivity of TWIST and VIBE assessment was equivalent (p=0.549 and p=0.344, respectively). Specificity and diagnostic accuracy were significantly higher for TWIST than for VIBE assessment (p<0.001). Inter-reader agreement in differentiating malignant from benign lesions was almost perfect for TWIST evaluation (κ=0.86) and substantial for conventional assessment (κ=0.75). CONCLUSIONS: TTE derived from ultrafast TWIST acquisitions is a valuable parameter that allows robust differentiation between malignant and benign breast lesions with high accuracy.

Segmentation of malignant lesions in 3D breast ultrasound using a depth-dependent model.

PURPOSE: Automated 3D breast ultrasound (ABUS) has been proposed as a complementary screening modality to mammography for early detection of breast cancers. To facilitate the interpretation of ABUS images, automated diagnosis and detection techniques are being developed, in which malignant lesion segmentation plays an important role. However, automated segmentation of cancer in ABUS is challenging since lesion edges might not be well defined. In this study, the authors aim at developing an automated segmentation method for malignant lesions in ABUS that is robust to ill-defined cancer edges and posterior shadowing. METHODS: A segmentation method using depth-guided dynamic programming based on spiral scanning is proposed. The method automatically adjusts aggressiveness of the segmentation according to the position of the voxels relative to the lesion center. Segmentation is more aggressive in the upper part of the lesion (close to the transducer) than at the bottom (far away from the transducer), where posterior shadowing is usually visible. The authors used Dice similarity coefficient (Dice) for evaluation. The proposed method is compared to existing state of the art approaches such as graph cut, level set, and smart opening and an existing dynamic programming method without depth dependence. RESULTS: In a dataset of 78 cancers, our proposed segmentation method achieved a mean Dice of 0.73 ± 0.14. The method outperforms an existing dynamic programming method (0.70 ± 0.16) on this task (p = 0.03) and it is also significantly (p < 0.001) better than graph cut (0.66 ± 0.18), level set based approach (0.63 ± 0.20) and smart opening (0.65 ± 0.12). CONCLUSIONS: The proposed depth-guided dynamic programming method achieves accurate breast malignant lesion segmentation results in automated breast ultrasound.

Mammographic and Ultrasonographic Findings of Oxidized Regenerated Cellulose in Breast Cancer Surgery: A 5-Year Experience.

BACKGROUND: The purpose of this study was to describe the ultrasonographic (US) and mammographic (MX) findings in patients who underwent breast-conserving surgery followed by oxidized regenerated cellulose (ORC) implantation in the surgical cavity and their size variations in follow-up. MATERIALS AND METHODS: We retrospectively reviewed 417 MX and 743 US images performed between January 2009 and January 2014 for 262 women who underwent breast-conserving surgery. All patients underwent US, only 203 women underwent MX examination. RESULTS: In 170 of 262 patients, US examinations showed abnormal findings. Three main US patterns were identified: (1) complex masses: well-encapsulated ipoisoechoic lesions with circumscribed margins with internal hyperechoic nodules (56%); (2) hypoanechoic lesions without internal hyperechoic nodules (24%); and (3) completely anechoic collections (20%). Moreover, Doppler ultrasound examination was performed on all of the patients. In 95 of 203 patients, MX examinations showed abnormalities. Four main MX patterns were identified: (1) round or oval opacity with circumscribed margins (58%); (2) round or oval opacity with indistinct or ill-defined margins (17%); (3) irregular opacity with indistinct or spiculated margins (9%); and (4) architectural distortion or focal asymmetry (15%). Most of the lesions showed a decrease in size at US and MX follow-up examination and the decrease was statistically significant (P < .01). CONCLUSION: When applied to the surgical residual cavity, ORC aids to control local hemorrhage and reduce the risk of postoperative infections, but can lead to alterations in surgical scar. Thus, knowledge of the radiological findings might allow avoidance of misdiagnosis of tumor recurrence or unnecessary diagnostic examinations.