Stiffness of salivary gland and tumor measured by new ultrasonic techniques: Virtual touch quantification and IQ

Normal value of virtual touch imaging quantification elastography in measurements of pancreas

OBJECTIVE

To evaluate pancreatic tissue stiffness and provide a normal reference shear wave velocity (SWV) value of pancreas from healthy adults by Virtual Touch Imaging Quantification (VTIQ) measurements.

METHODS

Healthy adult volunteers without known history of hepatobiliary or pancreatic diseases were included. VTIQ elastography (Siemens ACUSON Sequoia, 5C-1 transducer) was used. SWV values were measured at the cephalic, corpus and tail of pancreas and replicated different operators' obtained data. Subgroups were classified according to the volunteers' gender, age, body mass index (BMI), depth of measurements and the echogenicity of the pancreas.

RESULTS

From February 2023 to July 2023, 33 healthy adult volunteers were included. The success rate of VTIQ measurements in cephalic, corpus and tail regions was 90.90 % (30/33), 96.97 % (32/33) and 90.90 % (30/33) respectively. The color elastograms of healthy adult pancreas showed uniform blue or simultaneously blue and green. The average SWV values were 0.97±0.26 m/s for cephalic, 0.91±0.24 m/s for corpus and 0.97±0.25 m/s for pancreatic tail respectively (P = 0.198). The mean SWV values of pancreas did not show significant difference with age, gender or depth (P > 0.05). BMI was an influence factor in the measurements of SWV values of cephalic and tail of pancreas (P < 0.05). Pancreas with hyperechoic parenchyma showed higher mean SWV values (P < 0.05). The intra-observer (ICC = 0.938 [95% CI: 0.869-0.971]) and the inter-observer (ICC = 0.887 [95% CI: 0.760-0.947]) agreements of VTIQ measurements were excellent.

CONCLUSIONS

The mean SWV value of the pancreas in healthy adults was 0.96±0.20 m/s (range: 0.52-1.74 m/s). VTIQ technique can be used in pancreatic stiffness measurements with good reliability.

Current status of the diagnosis of chronic pancreatitis by ultrasonographic elastography

Chronic pancreatitis (CP) is pathologically characterized by the loss of exocrine pancreatic parenchyma, irregular fibrosis, cellular infiltration, and ductal abnormalities. Diagnosing CP objectively is difficult because standard diagnostic criteria are insufficient. The change of parenchymal hardness is the key factor for the diagnosis and understanding of the severity of CP. The ultrasonography (US) or endoscopic ultrasonography (EUS) elastography have been used to diagnose pancreatic diseases. Both strain elastography (SE) and shear wave elastography are specific diagnostic techniques for measuring tissue hardness. Most previous studies were conducted with SE. There are three methods of interpreting SE; the method of recognizing the patterns in SE distribution images in the region of interest, the method of using strain ratio to compare the hardness of adipose tissue or connective tissue with that of the lesion, and the method of evaluating the hardness distribution of a target by histogram analysis. These former two methods have been used primarily for neoplastic diseases, and histograms analysis has been used to assess hardness distribution in the evaluation of CP. Since the hardness of the pancreas increases with aging, it is necessary to consider the age in the diagnosis of pancreatic disorders using US or EUS elastography.

Can Ultrasound in Combination with Virtual Touch Imaging Quantification Predict the Dignity of a Parotid Tumor?

Pre-operative evaluation of a parotid gland tumor is crucial in guiding treatment. This study evaluates the diagnostic performance of B-mode ultrasound in combination with Virtual Touch imaging quantification (VTIQ) in the assessment of parotid lesions. A prospective study of 268 patients with parotid lesions was conducted. Pre-operative ultrasound findings and VTIQ data were compared against histologic results. Ill-defined margins on ultrasound were associated with a significantly higher risk of malignancy (odds ratio [OR] = 1224.0, 95 % confidence interval [CI]: 151.8-9872.7). Faster mean shear waves on VTIQ (OR = 1.81, 95% CI: 1.47-2.23, per 1 m/s increase) and an area with shear wave velocity >6.0 m/s involving >70 % of the lesion (OR = 19.80, 95 % CI: 6.22-63.07) were associated with higher risk of malignancy. Addition of VTIQ to routine pre-operative B-mode ultrasound can provide supplemental information on the dignity of a parotid tumor, allowing for peri-operative procedural optimization.

Comparison of the diagnostic value of virtual touch tissue quantification and virtual touch tissue imaging quantification in infants with biliary atresia

OBJECTIVE

This study aimed to compare the diagnostic performance of vital touch tissue quantification (VTQ) and virtual touch tissue imaging quantification (VTIQ) in diagnosing infants with biliary atresia (BA) from jaundiced infants.

METHODS

In this study, 26 jaundiced infants with BA, 33 jaundiced infants without BA, and 40 normal infants were enrolled. The hepatic shear wave velocity (SWV) of each infant was determined by VTQ and VTIQ examinations, respectively. Then, the receiver operating characteristic (ROC) curves were drawn and the area under the curve (AUC) and optimal cut-off values were calculated to evaluate the sensitivities and specificities of VTIQ and VTQ for BA.

RESULTS

The mean values of SWV of the control group measured by VTQ and VTIQ were (1.09 ± 0.18) m/s and (1.36 ± 0.21) m/s, respectively. The mean values of SWV of the non-BA group measured by VTQ and VTIQ were (1.30 ± 0.28) m/s and (1.52 ± 0.29) m/s, respectively. The mean values of SWV of the BA group measured by VTQ and VTIQ were (2.36 ± 0.36) m/s and (2.43 ± 0.29) m/s, respectively. The diagnostic threshold of VTQ and VTIQ to diagnose BA was 1.77 and 1.92 m/s. The sensitivities of VTQ and VTIQ to diagnose BA were 90.9% and 95.5%. The specificities of VTQ and VTIQ to diagnose BA were 68.4% and 78.9%.

CONCLUSION

Vital touch tissue quantification and VTIQ could help distinguish infants with BA from jaundiced infants by measuring the liver SWV values. VTIQ has higher sensitivity and specificity than VTQ.

The current value of quantitative shear wave sonoelastography in parotid gland tumors

Background

The preoperative differentiation between salivary gland tumor entities using computed tomography, magnetic resonance imaging (MRI) and ultrasound (US) is still limited. Biopsies are often regarded as indispensable for properly characterizing these various lesions. The aim of this study was to analyze the value of acoustic radiation force impulse (ARFI) sonoelastography as an US differentiation tool when examining parotid gland (PG) lesions.

Methods

We included 104 patients with PG masses in this study, employing two different US devices using quantitative ARFI-sonoelastography (Siemens Acuson-S3000, n=59; Siemens Acuson-Sequoia, n=45). The ability of sonoelastographic measurements to differentiate between different neoplasms was compared and analyzed for both US machines.

Results

Quantitative shear wave sonoelastography is limited in its ability to reliably differentiate between tumor entities of the PG as a stand-alone parameter. Measurement results were unsystematically distributed and not transferable between the two US devices. A significant differentiation of benign and malignant lesions was not possible with either US machine (S3000: P=0.770, Sequoia: P=0.382). A differentiation between pleomorphic adenomas (PA) and Warthin tumors was only possible with the Acuson S3000 system (P=0.001, Spearman-Rho =0.492, sensitivity 73.9%, specificity 65.0%).

Conclusions

A reliable identification and differentiation of PG tumors as well as clinical treatment decisions cannot be made with the sole use of ARFI-sonoelastography. The results emphasize the device-dependence and high error-proneness of this US technique when examining lesions of the PG.

Application of virtual touch tissue imaging quantification in diagnosis of supraspinatus tendon injury

OBJECTIVE

To explore the value of virtual touch imaging and quantification (VTIQ) shear wave elastography (SWE) in diagnosis of supraspinatus tendon tear.

METHODS

Eighty patients with unilateral supraspinatus tendon tear underwent shoulder arthroscopy were prospective studied. Tendinopathy, partial-thickness tear or full-thickness tear of supraspinatus tendon were diagnosed according 2D ultrasound examination. Sensitivity, specificity and accuracy of ultrasonic diagnosis of supraspinatus tendon tear were calculated by arthroscopy as the gold standard. VTIQ was applied to measure the shear-wave velocity (SWV) of both normal and affected supraspinatus tendon. The differences of SWV in three types of supraspinatus tendon tear and receiver operating characteristic (ROC) curves were analyzed.

RESULTS

Among 80 patients, there were 20 tendinopathy, 31 partial tears and 29 full-thickness tears diagnosed by shoulder arthroscopy. Sensitivity, specificity and accuracy of 2D ultrasound in diagnosis of tendinopathy, partial tear and full-thickness tear groups were 78%, 90%and 83%; 71%, 86%and 73%; 86%, 88%and 88%, respectively. SWV of 80 supraspinatus tendon tears was 4.59±1.00 m/s, which was lower than that of normal supraspinatus tendon (4.59±1.00 m/s vs. 6.68±1.05 m/s, P < 0.01). SWV of supraspinatus tendon in tendinopathy, partial tear and full-thickness tear groups respectively were 5.66±0.97, 4.66±1.00, and 3.78±0.55 m/s, all lower than that of the contralateral normal supraspinatus tendon (all P < 0.05). In addition, the analysis of variance and pairwise comparison showed that SWV of supraspinatus tendon among three different degree of injury was statistically significant (all P < 0.001). The cutoff thresholds of SWV was 4.83 m/s to identify tendinopathy tear from partial tear and was 4.08 m/s to identify full-thickness tear from partial-thickness tear.

CONCLUSION

VTIQ SWE with SWV might identify degree of supraspinatus tendon tear and improve the value of ultrasonography, which should be further evaluated in large multicenter studies.

Multimodal Ultrasound Including Virtual Touch Imaging Quantification for Differentiating Cervical Lymph Nodes

Defining the entity of cervical lymph nodes (LNs) is essential for the diagnosis and staging of head and neck malignancies. Virtual Touch imaging quantification (VTIQ) is a relatively new method of elastography that measures tissue stiffness quantitatively. A prospective study was conducted that included 108 patients (57 benign and 51 metastatic lymph nodes [MLNs]). Shear wave velocities (SWVs) were analyzed using VTIQ and were compared with the histopathological results. Both maximum and minimum SWVs within the LNs significantly differed between benign masses and MLNs (p < 0.001). Percentage areas of the node with SWVs >6 m/s and <3.5 m/s differed significantly (p < 0.001). Intralesional areas with SWVs ≤3.5 m/s of 0-29% (odds ratio: 93.7) and 30%-69% (odds ratio: 46.3) were predictive of malignant LNs as well as ill-defined tumor (odds ratio: 5.2). VTIQ can provide more information on the entity of cervical LNs.

ACR Appropriateness Criteria® Neck Mass-Adenopathy

A palpable neck mass may be the result of neoplastic, congenital, or inflammatory disease. Older age suggests neoplasia, and a congenital etiology is more prevalent in the pediatric population. The imaging approach is based on the patient age, mass location, and clinical pulsatility. Underlying human papillomavirus-related malignancy should be considered in all age groups. Although the imaging appearance of some processes in the head and neck overlap, choosing the appropriate imaging examination may allow a specific diagnosis, or a limited differential diagnosis. Tissue sampling is indicated to confirm suspected malignancy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

The Utility of Major Salivary Gland Ultrasonographic Parameters in the Diagnosis of Sjögren Syndrome

Objective

To investigate ultrasonographically the salivary glands and to correlate ultrasonographic parameters with focus score, serum beta-2-microglobulin, and stimulated salivary flow rate.

Material and Methods

32 patients with primary Sjögren's syndrome (pSS) and 32 healthy controls were enrolled in this case-control study, performed in the Department of Internal Medicine, Division of Rheumatology, "Victor Babeș" University of Medicine and Pharmacy, Timișoara, Romania. All the patients and controls were examined by salivary gland ultrasonography (B-mode, color and spectral Doppler, and sonoelastography), determining the following parameters: salivary gland ultrasonography (SGUS) score, resistive index (RI) of transverse facial artery, and shear wave velocity (SWV). Serum beta-2-microglobulin and stimulated saliva amount were determined in all the patients and controls. Minor salivary gland biopsy with focus score assessment was done in pSS patients.

Results

Patients with pSS presented higher SGUS score and parotid and submandibular SWV and reduced RI of transverse facial artery than controls (p < 0.0001). In pSS patients, statistically significant correlations were identified between assessed ultrasonographic parameters and focus score, serum beta-2-microglobulin, and respective stimulated saliva flow (p < 0.0001).

Conclusions

This study highlighted statistically significant correlations between salivary gland ultrasonographic parameters and focus score, serum beta-2-microglobulin, and stimulated saliva flow.

Shear Wave Elastography Improves Specificity of Ultrasound for Parotid Nodules

OBJECTIVES

This study aimed to determine the performance of Virtual Touch tissue quantification (VTQ) technique in the differential evaluation of parotid gland nodules.

METHODS

Acoustic radiation force impulse VTQ technique was used to determine the shear wave velocity (SWV) of 76 patients with parotid nodules and 30 subjects with normal parotid gland. These nodules were assigned to benign and malignant nodules according to histopathology, measurements of SWV were compared, a cutoff point for benign and malignant nodules was obtained with reference to receiver-operating characteristic curve, and relevant sensitivity and specificity were evaluated.

RESULTS

There were 61 of 76 patients with benign parotid nodules and 15 of 76 patients with malignant nodules. The SWV of the malignant nodules was higher than the SWV of the benign nodules, and the SWV of the benign and malignant nodules was higher than the normal parotid glands. There were significant differences between benign and malignant nodules as well as normal parotid glands in terms of the age and SWV of the nodules (all P < 0.001). The area under the curve is 0.893, the cutoff is 2.445 m/s, and the sensitivity and specificity are 80.0% and 91.8%, respectively.

CONCLUSIONS

Acoustic radiation force impulse VTQ technique can determine the stiffness of parotid nodules in general, its ability to distinct malignant from benign nodular nodule is still not strong, and overlay of SWV of VTQ between benign and malignant nodules is the main impedance to set cutoff point.

Clinical value of the VTIQ technology in the differential diagnosis of superficially enlarged lymph nodes

Background Lymph node enlargement is a common clinical finding in clinical practice with different treatment strategies. Purpose To investigate the application of Virtual Touch Image Quantification (VTIQ) to diagnose benign and malignant superficial enlarged lymph nodes. Material and Methods Between December 2015 and August 2016, 116 superficial enlarged lymph nodes were examined by VTIQ. Maximum (V_max), minimum (V_min), and average (V_mean) shear wave velocities (SWV) were obtained from the lymph nodes and from normal muscular tissues (V_n) located at the same level and within 5 mm from the target lymph node. The pathological results were used as the gold standard to evaluate VTIQ. Results All 116 patients underwent fine-needle aspiration biopsy for pathological examination. Forty patients had malignant lymph nodes and 76 patients had benign lymph nodes. Lymph node characteristics on B-mode ultrasound showed no differences between malignant and benign lymph nodes, but there were differences in VTIQ parameters (all P < 0.001). Compared with pathological diagnosis as the gold standard, the area under the ROC curves of V_max, V_min, and V_mean were 0.815, 0.746, and 0.795. The V_max cutoff value to diagnose benign from malignant lymph nodes was 3.045 m/s. The sensitivity, specificity, and positive and negative predictive values were 70%, 78.9%, 63.6%, and 83.3%. Conclusion VTIQ has a clinical application in the differential diagnosis of superficial enlarged lymph nodes.

Does acoustic radiation force elastography improve the diagnostic capability of ultrasound in the preoperative characterization of masses of the parotid gland?

OBJECTIVES:

Ultrasound is the method of choice for preoperative evaluation of tumours of the parotid glands. However, existing methods do not allow for clear differentiation between the most common benign tumours and malignant tumours. The aim of our study was to evaluate if acoustic radiation force, Virtual Touch Quantification (VTQ) elastography helps to improve the preoperative evaluation of parotid masses.

METHODS:

We investigated the parenchyma of 102 parotid glands, 14 lymph nodes of healthy volunteers and 51 tumours of the parotid gland via ultrasound, colour Doppler ultrasound and VTQ. The results were matched with histopathology and analyzed.

RESULTS:

The perfusion in pleomorphic adenoma, the most frequent benign tumour of the parotid gland, was significantly lower in comparison to malignant tumours. All tumours showed statistically significant higher perfusion in comparison to the parenchyma or the lymph nodes of the gland. Shear wave velocity of the user-defined region of interest was statistically significant more frequently an overflow value higher than 8.5 m/s in total tumours in comparison to parenchyma or lymph nodes. The different tumour types presented no significant difference in the shear wave velocity.

CONCLUSIONS:

VTQ in combination with classical ultrasound examination provides additional data useful in distinguishing between benign and malignant tumours and thus shows promise for integration into preexisting ultrasound protocols. However, despite the improvement, clear differentiation of tumours is still not possible and further investigation is recommended.

Does Virtual Touch IQ elastography help to improve the preoperative diagnosis of parotid tumors: A prospective trial

BACKGROUND

It is difficult to assess tumors of the parotid gland preoperatively. However, it is essential for the surgeon to know which kind of tumor is present. Ultrasound is the method of choice, but there is still no reliable differential diagnostic tool for determining whether a tumor is malignant or benign.

OBJECTIVE

The aim of our study was to examine the value of Virtual Touch imaging quantification (VTIQ) elastograpy in distinguishing between malignant and benign tumors as well as in identifying the most common benign tumor types.

METHODS

The parenchyma of 100 parotid glands and 12 lymph nodes of healthy volunteers and 50 tumors of the parotid gland were analyzed via ultrasound, color Doppler ultrasound, and VTIQ, and the results were then compared with histopathology.

RESULTS

In comparison with benign tumors, in malignant tumors the tumor border was diffuse, the perfusion higher, and the VTIQ quality much lower. Share wave velocity of the user-defined region of interest was more frequently higher than 6.8 m/s in malignant tumors in comparison to benign tumors.

CONCLUSIONS

VTIQ in combination with ultrasound examination provides additional information for distinguishing between benign and malignant tumors and shows promise for integration into preexisting ultrasound protocols.

Comparison of Virtual Touch Tissue Imaging & Quantification (VTIQ) and Virtual Touch Tissue Quantification (VTQ) for diagnosis of thyroid nodules

OBJECTIVE

The aim of this study was to compare the diagnostic performance of Virtual Touch Tissue Imaging & Quantification (VTIQ) and Virtual Touch Tissue Quantification (VTQ) in differentiating benign from malignant thyroid nodules (TNs).

MATERIALS AND METHODS

In this study 107 TNs in 107 patients were enrolled and analyzed. All of them were detected by conventional ultrasound (US) and confirmed by fine-needle aspiration (FNA) biopsy or surgery. VTIQ and VTQ examinations were performed on each nodule. Thereafter the median and mean of shear wave speed (SWS) values in lesions on VTIQ and VTQ were computed (SWS-median and SWS-mean). With cytological results of FNA and histological results adopted as the reference standard, area under the receiver operating characteristic (AUROC) curve analysis was performed to evaluate the diagnostic efficiency of VTIQ and VTQ in differentiation of TNs.

RESULTS

Among the 107 lesions, 19 were papillary thyroid carcinomas (PTCs), 1 was medullary thyroid carcinoma (MTC) and 87 were benign. In total lesions, AUROC-median in VTIQ was significantly higher than that in VTQ (0.851 vs.0.759; p < 0.05).

CONCLUSION

VTIQ and VTQ were equivalent in diagnosing TNs when using SWS-mean, whereas VTIQ showed better performance in comparison with VTQ when using SWS-median.

Preliminary Evaluation of Virtual Touch Tissue Imaging Quantification for Differential Diagnosis of Metastatic and Nonmetastatic Cervical Lymph Nodes

OBJECTIVES

Virtual Touch tissue imaging quantification (VTIQ; Siemens Medical Solutions, Mountain View, CA) is useful for assessing tissue hardness. This study aimed to investigate the value of VTIQ in differential diagnosis of cervical lymph nodes.

METHODS

We retrospectively analyzed conventional sonograms and VTIQ images of 85 pathologically confirmed patients with superficial lymph node lesions. Conventional sonography was first performed, with 2-dimensional images described. Then VTIQ shear wave velocity (SWV) values of superficial lymph nodes were measured. With pathologic diagnosis as the reference standard, a receiver operating characteristic curve was generated to evaluate VTIQ efficacy in differential diagnosis of metastatic and nonmetastatic cervical lymph nodes.

RESULTS

Of the 85 nodes, 44 and 41 were metastatic and nonmetastatic, respectively. The latter group included 24 and 17 hematologic/lymphatic system disease and reactive hyperplastic nodes, respectively. Shear wave velocity values of metastatic nodes were significantly higher than those of their nonmetastatic counterparts (P < .001). With an area under the curve (AUC) of 0.953 and SWV cutoff of 3.27 m/s, accuracy, sensitivity, and specificity were 89.4%, 88.6%, and 90.2%, respectively, for distinguishing metastatic and nonmetastatic nodes. An AUC of 0.943 and SWV cutoff of 3.23 m/s yielded accuracy, sensitivity, and specificity of 88.2%, 88.6%, and 87.5% for differentiating metastatic from hematologic/lymphatic system disease nodes. Finally, an AUC of 0.968 and SWV cutoff of 3.27 m/s yielded accuracy, sensitivity, and specificity of 90.2%, 88.6%, and 94.1% for differentiating metastatic from reactive hyperplastic nodes.

CONCLUSIONS

Virtual Touch tissue imaging quantification is efficient in differential diagnosis of metastatic and nonmetastatic cervical lymph nodes.

Virtual Touch Tissue Imaging and Quantification in the Evaluation of Thyroid Nodules

OBJECTIVES

To investigate the diagnostic performance of a 2-dimensional shear wave elastographic technique (Virtual Touch tissue imaging and quantification [VTIQ]; Siemens Medical Solutions, Mountain View, CA) for predicting thyroid malignancy.

METHODS

A total of 302 thyroid nodules underwent conventional sonography and VTIQ before fine-needle aspiration examination or surgery. Compared with histopathologic or cytologic results in combination with follow-up, the diagnostic performance of various shear wave speed (SWS) indices (minimum [SWS_min ], maximum [SWS_max ], and mean [SWS_mean ]) on VTIQ as well as conventional sonographic features for predicting thyroid malignancy was evaluated in all of the nodules.

RESULTS

Sixty-five malignant and 237 benign thyroid nodules were histopathologically or cytologically confirmed. All SWS indices on VTIQ were lower in benign nodules than thyroid malignancy (all P < .001). For discrimination between malignant and benign nodules, all VTIQ SWS indices were better than conventional sonographic features, such as a solid component, a taller-than-wide shape, microcalcification, a poorly defined margin and hypoechogenicity, in predicting thyroid malignancy (all P < .05). By applying a cutoff SWS_mean value of 2.60 m/s, VTIQ achieved sensitivity and negative predictive values of 84.6% and 94.3%, respectively, for differentiating nodules. The areas under the receiver operating characteristic curve of SWS_max (0.862 versus 0.717), SWS_min (0.866 versus 0.717), and SWS_mean (0.891 versus 0.725) for nodules larger than 10 mm were higher than those for nodules of 10 mm or smaller (all P < .05). Interoperator and intraoperator reproducibility was proven to be excellent, with all interclass correlation coefficient values higher than 0.80 (range, 0.813-0.905) CONCLUSIONS: Virtual Touch tissue imaging and quantification is a useful and reproducible tool for predicting thyroid malignancy.

Virtual Touch Quantification of the Salivary Glands for Diagnosis of Primary Sjögren Syndrome

OBJECTIVES

To investigate the value of salivary gland stiffness measured by Virtual Touch quantification (VTQ; Siemens Medical Solutions, Erlangen, Germany) for assessment of primary Sjögren syndrome.

METHODS

Fifty-four patients with primary Sjögren syndrome, 35 patients without primary Sjögren syndrome (patients with dry mouth and dry eye symptoms), and 52 healthy control volunteers were included in this study. Patients with primary Sjögren syndrome were classified as early or advanced stage by labial gland biopsies. All participants underwent B-mode sonography, on which the salivary glands (parotid and submandibular) were identified and VTQ measurements of shear wave velocity (SWV) were obtained. The diagnostic performance of SWV was evaluated by sensitivity and specificity at the optimum cutoff point and the area under the receiver operating characteristic curve.

RESULTS

For submandibular glands, the mean SWV ± SD values were 2.25 ± 0.34 m/s in patients with early-stage primary Sjögren, 1.84 ± 0.20 m/s in patients without primary Sjögren syndrome, and 1.82 ± 0.27 m/s in healthy controls (P< .001). With cutoff values of 2.15 and 2.10 m/s to separate patients with early-stage primary Sjögren syndrome from those without Sjögren syndrome and healthy controls, the sensitivity and specificity were 77.1% and 85.4% and 79.2% and 83.9%, respectively. For parotid glands, the SWV values were 2.78 ± 0.82 m/s in patients with early-stage primary Sjögren syndrome, 1.93 ± 0.33 m/s, in patients without primary Sjögren syndrome, and 1.85 ± 0.31 m/s in healthy controls (P < .001). With cutoff values of 2.18 and 2.10 m/s to separate patients with early-stage primary Sjögren syndrome from those without Sjögren syndrome and healthy controls, the sensitivity and specificity were 89.3 % and 75.3% and 91.4% and 80.0%.

CONCLUSIONS

The VTQ technique might be a useful noninvasive strategy for assessment of salivary glands in the early stage of primary Sjögren syndrome.

Acoustic Radiation Force Impulse Imaging for the Differentiation of Benign and Malignant Lymph Nodes: A Systematic Review and Meta-Analysis

Objective

To evaluate the overall performance of acoustic radiation force impulse imaging (ARFI) in differentiating between benign and malignant lymph nodes (LNs) by conducting a meta-analysis.

Methods

PubMed, Embase, Web of Science, the Cochrane Library and the China National Knowledge Infrastructure were comprehensively searched for potential studies through August 13th, 2016. Studies that investigated the diagnostic power of ARFI for the differential diagnosis of benign and malignant LNs by using virtual touch tissue quantification (VTQ) or virtual touch tissue imaging quantification (VTIQ) were collected. The included articles were published in English or Chinese. Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was used to evaluate the methodological quality. The pooled sensitivity, specificity, and the area under the summary receiver operating characteristic (SROC) curve (AUC) were calculated by means of a bivariate mixed-effects regression model. Meta-regression analysis was performed to identify the potential sources of between study heterogeneity. Fagan plot analysis was used to explore the clinical utilities. Publication bias was assessed using Deek’s funnel plot.

Results

Nine studies involving 1084 LNs from 929 patients were identified to analyze in the meta-analysis. The summary sensitivity and specificity of ARFI in detecting malignant LNs were 0.87 (95% confidence interval [CI], 0.83–0.91) and 0.88 (95% CI, 0.82–0.92), respectively. The AUC was 0.93 (95% CI, 0.90–0.95). The pooled DOR was 49.59 (95% CI, 26.11–94.15). Deek’s funnel plot revealed no significant publication bias.

Conclusion

ARFI is a promising tool for the differentiation of benign and malignant LNs with high sensitivity and specificity.

Reproducibility of Acoustic Radiation Force Impulse Imaging in Thyroid and Salivary Glands with Experienced and Inexperienced Examiners

Acoustic radiation force impulse (ARFI) imaging enables the sonographic measurement of tissue stiffness. The aim of this study was to evaluate if experience in ARFI imaging influences the reproducibility of ARFI imaging of the head and neck. Three experienced sonographers and three inexperienced sonographers performed ARFI imaging of thyroid, submandibular and parotid glands in 10 healthy volunteers. The examination was repeated after 2 wk. Ten single ARFI measurements were done in every gland. Inter-rater and intra-rater reliability was analyzed using the intra-class correlation coefficient (ICC). Moderate agreement was observed between experienced and inexperienced examiners (ICC = 0.46). In salivary glands, agreement was fair between the groups (ICC = 0.33), whereas in separate evaluations, inter-rater reliability in the submandibular glands was moderate (ICC = 0.52), and that in the parotid glands, only poor (ICC = 0.09). For ARFI imaging of the thyroid gland, there was moderate agreement between the groups (ICC = 0.50). The intra-rater reliability for the salivary and thyroid glands together and separately was strong in both groups. ARFI imaging of the thyroid and salivary glands did exhibit good reproducibility. ARFI imaging of the thyroid gland reached the highest levels of inter- and intra-observer agreement in both groups. ARFI imaging in salivary glands is only reproducible with experienced examiners.

Application of DTI and ARFI imaging in differential diagnosis of parotid tumours

OBJECTIVES

To explore the utility of diffusion tensor imaging (DTI) and acoustic radiation force impulse (ARFI) imaging in the diagnosis of parotid tumours.

METHODS

51 patients with parotid tumours were examined with DTI on 3.0-T MRI and ARFI imaging on an ultrasound scanner before surgery. Values of apparent diffusion coefficient (ADC), fractional anisotropy (FA) and shear-wave velocity (SWV) were calculated and analyzed with independent samples Wilcoxon-Mann-Whitney test. Cut-off values, sensitivity and specificity were calculated with receiver-operating characteristic (ROC) curve analysis. The value of combination was calculated through parallel test for the cut-off value of ADC, FA and SWV (combination = 0 or 1); then, ROC analysis was performed with pathological results as the gold standard to calculate the sensitivity and specificity for the combination of the three parameters distinguishing benign and malignant parotid tumours. Pathological diagnosis for every patient was made post-operatively from the tumour tissue taken during operation.

RESULTS

There was a significant difference between benign and malignant tumours in the values of ADC, FA and SWV (p = 0.032, p = 0.011 and p < 0.0001); a significant difference in the values was also found between pleomorphic adenoma and malignant tumour (p = 0.0012, p < 0.0001 and p = 0.0002). The diagnosis cut-off points between benign and malignant tumours for ADC, FA and SWV were 1.02 × 10(-3) mm(2) s(-1), 0.24 and 2.76 m s(-1), respectively; the sensitivity for ADC, FA and SWV was 87.50, 62.50 and 68.75%; the specificity was 45.71, 82.86 and 97.14%. Analysis of the combination of the three parameters increased the sensitivity, specificity, Youden index and area under the ROC curve compared with analysis of each parameter alone for distinguishing benign and malignant tumours.

CONCLUSIONS

The diagnostic value of the combination of the three parameters for distinguishing benign and malignant parotid tumours is the best; SWV is the preferred indicator. Parameters of DTI and ARFI may reflect the histological characteristics of parotid tumours and predict benignancy and malignancy and could provide quantitative information about the tumour. Combination of DTI with ARFI imaging had obvious advantage for the diagnosis of parotid tumours than each alone.

Assessment of the Stiffness of Major Salivary Glands in Primary Sjögren's Syndrome through Quantitative Acoustic Radiation Force Impulse Imaging

The purpose of the study described here was to evaluate salivary gland stiffness in primary Sjögren's syndrome (pSS) via acoustic radiation force impulse imaging, including Virtual Touch tissue quantification (VTQ) and Virtual Touch tissue imaging quantification (VTIQ). Twenty-one patients with pSS and 11 healthy patients were included, and the paired parotid and submandibular glands of all of the patients were examined using VTQ and VTIQ. Differences between the two groups were compared with independent and paired t-tests. The VTQ value for the parotid in the pSS group was significantly higher than that obtained for the control group (1.33 ± 0.22 and 1.18 ± 0.04 m/s, respectively, p < 0.01). The VTIQ values for the parotid and submandibular gland were both significantly higher in the pSS group than in the control group (p < 0.05). In the pSS group, a positive correlation was observed between the VTQ and VTIQ results for the parotid and submandibular glands. In summary, the stiffness of the major salivary glands in patients with pSS was increased compared with that of patients with normal glands. This finding indicates that VTQ and VTIQ imaging may be valuable adjuncts to gray-scale ultrasonography for the clinical diagnosis of pSS.

Virtual Touch Tissue Imaging Quantification Shear Wave Elastography: Prospective Assessment of Cervical Lymph Nodes

The goal of this study was to prospectively evaluate the diagnostic performance of Virtual Touch tissue imaging quantification (VTIQ) shear wave elastography in the discrimination of benign and malignant cervical lymph nodes in routine clinical practice. Shear wave velocity was analyzed using VTIQ in 100 patients with 100 histologically proven cervical lymph nodes. Diagnostic performance was evaluated using receiver operating characteristic curve analysis and leave-one-out cross-validation. Agreement between measurements was assessed with intra-class correlation coefficients. The mean shear wave velocity was significantly higher in metastatic lymphadenopathy (4.46 ± 1.46 m/s) than in benign lymphadenopathy (2.71 ± 0.85 m/s) (p < 0.001) at a cutoff level of 3.34 m/s. The cross-validated accuracy, sensitivity and specificity were 77%, 78.9% and 74.4%, respectively. Agreement of measurements with VTIQ was excellent (intra-class correlation coefficient = 0.961). VTIQ shear wave elastography may be a feasible quantitative imaging method for differentiating benign and malignant cervical lymph nodes.