Targeted detection of cancer cells during biopsy allows real-time diagnosis of pulmonary nodules.

BACKGROUND: The diagnostic yield of biopsies of solitary pulmonary nodules (SPNs) is low, particularly in sub-solid lesions. We developed a method (NIR-nCLE) to achieve cellular level cancer detection during biopsy by integrating (i) near-infrared (NIR) imaging using a cancer-targeted tracer (pafolacianine), and (ii) a flexible NIR confocal laser endomicroscopy (CLE) system that can fit within a biopsy needle. Our goal was to assess the diagnostic accuracy of NIR-nCLE ex vivo in SPNs. METHODS: Twenty patients with SPNs were preoperatively infused with pafolacianine. Following resection, specimens were inspected to identify the lesion of interest. NIR-nCLE imaging followed by tissue biopsy was performed within the lesion and in normal lung tissue. All imaging sequences (n = 115) were scored by 5 blinded raters on the presence of fluorescent cancer cells and compared to diagnoses by a thoracic pathologist. RESULTS: Most lesions (n = 15, 71%) were adenocarcinoma-spectrum malignancies, including 7 ground glass opacities (33%). Mean fluorescence intensity (MFI) by NIR-nCLE for tumor biopsy was 20.6 arbitrary units (A.U.) and mean MFI for normal lung was 6.4 A.U. (p < 0.001). Receiver operating characteristic analysis yielded a high area under the curve for MFI (AUC = 0.951). Blinded raters scored the NIR-nCLE sequences on the presence of fluorescent cancer cells with sensitivity and specificity of 98% and 97%, respectively. Overall diagnostic accuracy was 97%. The inter-observer agreement of the five raters was excellent (κ = 0.95). CONCLUSIONS: NIR-nCLE allows sensitive and specific detection of cancer cells in SPNs. This technology has far-reaching implications for diagnostic needle biopsies and intraprocedural decision-making.

Direct measurement of cardiac stiffness using echocardiographic shearwave imaging during open-chest surgery: A pilot study in human.

PURPOSE: Cardiac stiffness is a marker of diastolic function with a strong prognostic significance in many heart diseases that is not measurable in clinical practice. This study investigates whether elastometry, a surrogate for organ stiffness, is measurable in the heart using ShearWave Imaging. METHODS: In 33 anesthetized patients scheduled for cardiac surgery, ShearWave imaging was acquired epicardially using a dedicated ultrasound machine on the left ventricle parallel to the left anterior descending coronary artery in a loaded heart following the last cardiac beat. Cardiac elastometry was measured offline using the Young modulus with customized software. RESULTS: Overall, the ejection fraction was 61 ± 10%. E/A and E/e' ratios were 1.0 ± 0.5 and 10.5 ± 4.1, respectively. Cardiac elastometry averaged 15.3 ± 5.3 kPa with a median of 18 kPa. Patients with high elastometry >18 kPa were older (P = .04), had thicker (P = .02) but smaller LV (P = .004), had larger left atria (P = .05) and a higher BNP level (P = .04). We distinguished three different transmural elastometry patterns: higher epicardial, higher endocardial, or uniformly distributed elastometry. CONCLUSION: Elastometry measurement was feasible for the human heart. This surrogate for cardiac stiffness dichotomized patients with low and high elastometry, and provided three different phenotypes of transmural elastometry with link to diastolic function.

Assessment of biopsy-proven liver fibrosis by two-dimensional shear wave elastography: An individual patient data-based meta-analysis.

Two-dimensional shear wave elastography (2D-SWE) has proven to be efficient for the evaluation of liver fibrosis in small to moderate-sized clinical trials. We aimed at running a larger-scale meta-analysis of individual data. Centers which have worked with Aixplorer ultrasound equipment were contacted to share their data. Retrospective statistical analysis used direct and paired receiver operating characteristic and area under the receiver operating characteristic curve (AUROC) analyses, accounting for random effects. Data on both 2D-SWE and liver biopsy were available for 1,134 patients from 13 sites, as well as on successful transient elastography in 665 patients. Most patients had chronic hepatitis C (n = 379), hepatitis B (n = 400), or nonalcoholic fatty liver disease (n = 156). AUROCs of 2D-SWE in patients with hepatitis C, hepatitis B, and nonalcoholic fatty liver disease were 86.3%, 90.6%, and 85.5% for diagnosing significant fibrosis and 92.9%, 95.5%, and 91.7% for diagnosing cirrhosis, respectively. The AUROC of 2D-SWE was 0.022-0.084 (95% confidence interval) larger than the AUROC of transient elastography for diagnosing significant fibrosis (P = 0.001) and 0.003-0.034 for diagnosing cirrhosis (P = 0.022) in all patients. This difference was strongest in hepatitis B patients. CONCLUSION: 2D-SWE has good to excellent performance for the noninvasive staging of liver fibrosis in patients with hepatitis B; further prospective studies are needed for head-to-head comparison between 2D-SWE and other imaging modalities to establish disease-specific appropriate cutoff points for assessment of fibrosis stage. (Hepatology 2018;67:260-272).

Intraoperative confocal laser endomicroscopy for real-time in vivo tissue characterization during surgical procedures.

INTRODUCTION: Probe-based confocal laser endomicroscopy (pCLE) is an innovative technique providing real-time, in vivo optical biopsies. A previous ex vivo phase of the study (PERSEE) allowed identifying accurate pCLE criteria for the diagnosis of hepatic and peritoneal surgical specimens. This study aimed at evaluating the pCLE role for in vivo intra-abdominal tissue characterization during digestive cancer surgical procedures. METHODS: Between October 2014 and July 2015, consecutive patients diagnosed with digestive cancers and scheduled for a surgical resection or an exploratory laparoscopy were prospectively enrolled. Endomicroscopic images were acquired using a motorized Confocal Miniprobe™ with a bending distal tip providing easy access to abdominal organs. It was connected to an endomicroscopy system that allowed near-infrared illumination (at a wavelength of 785 nm) in conjunction with indocyanine green for contrast agent. A live audiovisual transmission was established between the surgeon and the pathologist for real-time interpretation of optical biopsies. Intraoperative pCLE performance for the diagnosis of suspicious nodules was assessed using corresponding surgical histopathology as reference standard. RESULTS: 21 consecutive patients were successfully enrolled. Live audiovisual transmission between the surgeon and the pathologist was successfully established in all cases. 62 pCLE sequences were acquired from different tissues [peritoneum (n = 27), liver (n = 21), lymph node (n = 4), diaphragm (n = 3), colon (n = 3), stomach (n = 2), and adrenal gland (n = 2)]. Malignant tissues were identified by fluorescently enhanced irregular cancerous tubes contrasting with dark glandular lumen and extracellular matrix. pCLE sensitivities and specificities were 67% and 100%, and 38% and 100% for peritoneal and hepatic carcinogenesis, respectively. One benign incident was reported during the trial with no patient consequence. CONCLUSIONS: Real-time intraoperative pCLE with near-infrared illumination is feasible and safe, provides additional information in terms of tissue characterization, and, in combination with telepathology, allows interactive collaboration between the surgeon and the pathologist during surgical procedures. Trial registration clinicaltrials.gov Identifier: NCT02312167.

Testicular ultrasensitive Doppler preliminary experience: a feasibility study.

Background Ultrasensitive Doppler is a novel non-invasive ultrasound (US) Doppler technique that improves sensitivity and resolution for the detection of slow flow. Purpose To investigate the feasibility of ultrasensitive Doppler (USD) for testicular disease diagnosis, using both qualitative and quantitative results. Material and Methods This prospective study was conducted in 160 successive men referred for scrotal US including B-mode and conventional Color-Doppler. A new USD sequence and algorithm dedicated to academic research were implemented into the US system. The quality criterion for a successful examination was the detection of well delineated intratesticular vessels. Qualitative USD results were described in terms of tumor vascular architecture and flow intensity for different pathologies for 41 patients. The testicular vascularization (TV), defined as a vessel's surface ratio, was quantified using customized MATLAB® software and compared in azoospermic and normal patients. Results USD was acquired successfully in 153/160 patients (95.6%). The tumor vascular architecture differed depending on the nature of the tumors. Leydig cell tumors exhibited mostly circumferential vascularization, while germ cell tumors exhibited straight vessels through the tumors, or anarchic vascular maps. USD improved the diagnostic performance of testicular Doppler US in a case of incomplete spermatic cord torsion and acute epididymitis. The reproducibility of TV measurements established an interclass correlation of 0.801. Non-Klinefelter syndrome non-obstructive azoospermia patients exhibited a lower TV compared to normal patients, to Klinefelter syndrome, and to obstructive azoospermia patients ( P < 0.002, P < 0.005, and P < 0.05, respectively). Conclusion Testicular USD can become a promising technique for improving US diagnosis of tumors, acute scrotum, and for determining infertility status.

Feasibility of Imaging and Treatment Monitoring of Breast Lesions with Three-Dimensional Shear Wave Elastography.

Purpose Firstly to evaluate the feasibility and diagnostic performance of three-dimensional (3 D) shear wave elastography (SWE) volume measurements in patients with breast lesions compared to breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) lesion volumes and 3D-US B-mode volumes. Secondly to assess the treatment monitoring performance of 3D-SWE in patients under neoadjuvant chemotherapy for breast cancer by comparing it to 3D-US lesion volume. Materials and Methods This prospective study was approved by the institutional review board. Informed consent was provided. 33 patients with 33 lesions were included. The feasibility of 3D-SWE was evaluated in 23 patients. In the 10 remaining patients receiving neoadjuvant chemotherapy, 3D-SWE was evaluated before and during treatment. Tumor volume and qualitative and quantitative elasticity analysis measurements were performed and compared to the tumor volume as estimated by 3D-US and DCE-MRI. Statistical analysis was performed using the Pearson correlation coefficient. Results 3D-SWE was feasible in patients with breast lesions. Tumor volume calculated with 3D-US and 3D-SWE showed very good and moderate concordances with DCE-MRI volume, respectively (Pearson correlation coefficients equal to ρ = r = 0.88, p < 0.00 002 and ρ = r = 0.5, p = 0.32, respectively). Modification of tumor elasticity and heterogeneity was correlated with response to treatment. In good responders, elasticity and elasticity heterogeneity diminished. Conclusion Tumor 3D-US volume measurements showed very good concordance with DCE-MRI volume. 3D-SWE can provide valuable information: reduction of tissue stiffness during treatment could be a potential indicator of response. These preliminary results should be confirmed on a larger number of patients.

Targeted detection of cancer at the cellular level during biopsy by near-infrared confocal laser endomicroscopy.

Suspicious nodules detected by radiography are often investigated by biopsy, but the diagnostic yield of biopsies of small nodules is poor. Here we report a method-NIR-nCLE-to detect cancer at the cellular level in real-time during biopsy. This technology integrates a cancer-targeted near-infrared (NIR) tracer with a needle-based confocal laser endomicroscopy (nCLE) system modified to detect NIR signal. We develop and test NIR-nCLE in preclinical models of pulmonary nodule biopsy including human specimens. We find that the technology has the resolution to identify a single cancer cell among normal fibroblast cells when co-cultured at a ratio of 1:1000, and can detect cancer cells in human tumors less than 2 cm in diameter. The NIR-nCLE technology rapidly delivers images that permit accurate discrimination between tumor and normal tissue by non-experts. This proof-of-concept study analyzes pulmonary nodules as a test case, but the results may be generalizable to other malignancies.

Characterization of Testicular Masses in Adults: Performance of Combined Quantitative Shear Wave Elastography and Conventional Ultrasound.

We prospectively evaluated the performance of combined shear wave elastography (SWE) and conventional ultrasound (US) for the characterization of 89 testicular focal masses. Testes were evaluated with B-mode, color Doppler and SWE measurements, locating a region of interest on the normal and pathologic parenchyma. Thirty-seven malignant tumors (MTs), 12 burned out tumors (BOTs), 28 Leydig cell tumors (LCTs), 2 dermoid cysts and other benign lesions were included. MTs + BOTs exhibited more microliths and macrocalcifications compared with benign lesions (p < 10-4). LCTs manifested mostly a dominant peripheral vascularization pattern compared with other lesions. MTs + BOTs were stiffer compared with benign lesions (p < 2 × 10-4) but with a moderate area under the receiver operating characteristic curve (AUROC) of 80%. By focusing on LCTs versus MTs + BOTs, diagnostic performance led to an AUROC of 89% for the best stiffness parameter. For combined conventional US and SWE, the diagnostic performance to differentiate all benign lesions versus MTs + BOTs and LCTs versus MTs + BOTs increased to AUROCs of 93% and 98%, respectively.

Testicular Shear Wave Elastography in Normal and Infertile Men: A Prospective Study on 601 Patients.

Our aim in the study described here was to prospectively establish the feasibility of using and reproducibility of testicular shear-wave elastography in the assessment of testicular stiffness in 62 normal patients and 539 infertile men with obstructive azoospermia (OA), non-Klinefelter syndrome non-obstructive azoospermia (non-KS NOA), Klinefelter syndrome NOA (KS NOA), oligoasthenoteratozoospermia (OAT) or a left varicocele. The feasibility rate was 96.9%, with an intra-class correlation coefficient of 0.85 (95% confidence interval: 0.83-0.88). Median stiffness (interquartile range) values were 2.4 kPa (2.0, 2.9), 2.1 kPa (1.8, 2.5), 2.4 kPa (2.0, 2.7), 2.0 kPa (1.7, 2.4), 2.6 kPa (2, 3.2) and 2.2 kPa (1.8, 2.6) for men with a normal testis (n = 108), OAT (n = 689), OA (n = 119), non-KS NOA (n = 183), KS NOA (n = 70) and varicocele (n = 132), respectively. Testicular shear wave elastography is a feasible and reproducible technique. A significant positive association was found between stiffness and testis volume (p = 0.001). Testicular stiffness was higher in OA than in non-KS NOA populations (p = 1.e-10) and in KS NOA than in NOA populations (p = 2.0e-8), but the substantial number of overlapping values limited the clinical impact.

Velocity fluctuation reduction in vector Doppler ultrasound using a hybrid single/dual-beam algorithm.

In order to reduce the fluctuations in the velocity magnitude estimate, we propose a modification to the standard algorithm for reconstructing the (two component) vector velocity from the measured Doppler shifts in two directions. This uses the standard dual-beam algorithm, combined with temporal smoothing, to find only the velocity angle, then uses the single-beam algorithm to estimate the velocity magnitude. We present initial data showing the significant reduction in velocity estimate fluctuation that this hybrid method achieves compared to the standard algorithm.

Quantitative assessment of arterial wall biomechanical properties using shear wave imaging.

A new ultrasound-based technique is proposed to assess the arterial stiffness: the radiation force of an ultrasonic beam focused on the arterial wall induces a transient shear wave (∼10 ms) whose propagation is tracked by ultrafast imaging. The large and high-frequency content (100 to 1500 Hz) of the induced wave enables studying the wave dispersion, which is shown experimentally in vitro and numerically to be linked to arterial wall stiffness and geometry. The proposed method is applied in vivo. By repeating the acquisition up to 10 times per second (theoretical maximal frame rate is ∼100 Hz), it is possible to assess in vivo the arterial wall elasticity dynamics: shear modulus of a healthy volunteer carotid wall is shown to vary strongly during the cardiac cycle and measured to be 130 ± 15 kPa in systole and 80 ± 10 kPa in diastole.