Virtual Touch Tissue Imaging Quantification Research Articles

Acoustic radiation force impulse elastography for differentiation of benign and malignant thyroid nodules with concurrent Hashimoto’s thyroiditis

The purpose of the study was to explore the diagnostic performance of acoustic radiation force impulse (ARFI) elastography in differential diagnosis between benign and malignant thyroid nodules in patients with coexistent Hashimoto's thyroiditis (HT). A total of 141 pathological proven nodules in 141 HT patients (7 males and 134 females, mean age 50.1 years, range 23-75 years) received conventional ultrasound (US), elasticity imaging (EI) and ARFI elastography, including virtual touch tissue imaging (VTI) and virtual touch tissue quantification (VTQ), before surgery. Shear wave velocity (SWV) and SWV ratio were measured for each nodule on VTQ. The US, EI and ARFI elastography features were compared between benign and malignant nodules in HT patients. Receiver operating characteristic curve (ROC) analyses and area under curve (AUC) were performed to assess the diagnostic performance. Pathologically, 70 nodules were benign and 71 nodules were malignant. Significant differences were found between benign and malignant nodules in HT patients for EI (EI score) and ARFI (VTI grade and SWV) (all P value <0.05). The AUCs for EI, VTI, SWV and SWV ratio were 0.68 [95% confidence interval (CI): 0.59-0.77], 0.90 (95% CI: 0.84-0.95), 0.77 (95%CI: 0.70-0.85) and 0.74 (95%CI: 0.66-0.82), respectively. The cut-off points were EI score ≥3, VTI grade ≥4, SWV ≥2.58 m/s and SWV ratio ≥1.03, respectively. In conclusion, ARFI elastography is useful for differentiation between benign and malignant thyroid nodules in HT patients. The diagnostic performance of ARFI elastography is better than EI.

Solid Hypo-echoic Thyroid Nodules on Ultrasound: The Diagnostic Value of Acoustic Radiation Force Impulse Elastography

The aim of the study described here was to evaluate the diagnostic performance of acoustic radiation force impulse (ARFI) elastography in the differential diagnosis between benign and malignant solid hypo-echoic thyroid nodules (SHTNs) on ultrasound. In this retrospective study, 183 histologically proven SHTNs in 159 patients were enrolled. Conventional US, as well as Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (VTQ) of ARFI elastography, was performed on each nodule. The VTI features of SHTNs were divided into six grades, where higher grades represent harder tissue. VTQ was expressed as shear wave velocity, where higher shear wave velocity values indicate stiffer tissue. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and Youden index for ultrasound and ARFI were assessed. The 183 pathologically proven SHTNs included 117 benign and 66 malignant lesions. Nodules classified as VTI grades IV to VI were more frequently malignant (49/66, 74.2%) than benign (10/117, 8.5%) (p < 0.001). The mean shear wave velocity of VTQ for malignant SHTNs (mean ± standard deviation, 4.65 ± 2.68 m/s; range, 1.36–9 m/s) was significantly higher than that for benign SHTNs (2.34 ± 0.85 m/s, 0–5.7 m/s) (p < 0.001). The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and Youden index were 27.3%–84.8%, 13.7%–89.7%, 39.3%–69.4%, 35.7%–60%, 61.5%–78.5%, and –0.015 to 0.37 for ultrasound; 68.2%, 76.9%, 73.8%, 62.5%, 81.1% and 0.451 for VTQ; and 74.2%, 91.5%, 85.2%, 83.1%, 86.3% and 0.657 for VTI, respectively. ARFI elastography performed at a superior level, compared with conventional ultrasound, in the differential diagnosis between malignant and benign SHTNs. The diagnostic performance of VTI is higher than that of VTQ.

Applicative value of acoustic radiation force impulse imaging in differential diagnosis of small hypoechoic thyroid nodules

Objective To investigate the applicative value of acoustic radiation force impulse imaging (ARFI) in the differential diagnosis of small hypoechoic thyroid nodules.Methods 31 patients were pathologically confirmed as having a total of 44 small hypoechoic thyroid nodules ≤ 1 cm in diameter,followed by analyses of the characteristics of their ARFI images,including virtual touch tissue imaging (VTI) and virtual touch tissue quantification (VTQ).Based on VTI images of the nodules,the hardness of small hypoechoic thyroid nodules was respectively scored,and the ratios of VTI images to gray scale image areas were calculated.With pathological diagnosis as the gold standard,VTI scores,area ratios and VTQ values of the ROC curve in diagnosis of thyroid malignant nodules were sketched so as to explore the optimal cut-off points in VTI scores,area ratios and VTQ values in the diagnosis of malignant nodules.Results By the ROC curve test,VTI score of 3 was determined as the cut-off point of areas ratio,with the sensitivity and specificity of diagnosing thyroid cancer being 96.0 ％ and 94.7％,respectively.There were 34 nodules with VTI score greater than 3 (including 9 benign nodules and 25 malignant nodules) and 10 nodules with VTI score of 3 or less (all benign nodules).Malignant thyroid nodules had higher ratio of VTI images to gray scale image area than that of the benign nodules (1.58 ± 0.18 vs 1.30 ± 0.10,P ＜0.05).When 1.47 was set as the cut-off point of areas ratio,the sensitivity and specificity of diagnosing thyroid cancer were 80.0％ and 94.7％,respectively.The VTQ value of 2.76 m/s in diagnosis of thyroid malignant nodules was designated as the cut-off point,with a sensitivity of 88.0 ％,specificity of 94.7 ％.Conclusions The ARFI technique is able to provide information of thyroid nodule hardness,which guarantees its high applicative value in the differential diagnosis of small hypoechoic thyroid nodules. Key words: Ultrasonography; Thyroid nodule ; Acoustic radiation force impulse imaging

Evaluation of virtual touch tissue imaging quantification, a new shear wave velocity imaging method, for breast lesion assessment by ultrasound.

Objectives. To evaluate virtual touch tissue imaging quantification (VTIQ) as a new elastography method concerning its intra- and interexaminer reliability and its ability to differentiate benign from malignant breast lesions in comparison to and in combination with ultrasound (US) B-mode breast imaging reporting and data system (BI-RADS) assessment. Materials and Methods. US and VTIQ were performed by two examiners in 103 women with 104 lesions. Intra- and interexaminer reliability of VTIQ was assessed. The area under the receiver operating curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of BIRADS, VTIQ, and combined data were compared. Results. Fifty-four of 104 lesions were malignant. Intraexaminer reliability was consistent, and interexaminer agreement showed a strong positive correlation (r = 0.93). The mean VTIQ values in malignant lesions were significantly higher than those in benign (7.73 m/s ± 1.02 versus 4.46 m/s ± 1.87; P < 0.0001). The combination of US-BIRADS with the optimal cut-off for clinical decision making of 5.18 m/s yielded a sensitivity of 98%, specificity of 82%, PPV of 86%, and NPV of 98%. The combination of BIRADS and VTIQ led to improved test validity. Conclusion. VTIQ is highly reliable and reproducible. There is a significant difference regarding the mean maximum velocity of benign and malignant lesions. Adding VTIQ to BIRADS assessment improves the specificity.

The role of VTIQ as a new tissue strain analytics measurement technique in testicular lesions.

Virtual touch tissue imaging quantification (VTIQ) is a newly developed technique for the sonographic quantification of tissue elasticity. It has been used in the assessment of breast lesions. The purpose of this study was to determine the diagnostic performance of VTIQ in indeterminate testicular lesions. Twenty patients with known testicular pathology underwent conventional B-mode sonography with additional VTIQ of the testicular lesions using a Siemens Acuson S2000™ and S3000™ (Siemens Medical Solutions, Mountain View, CA, USA) system. Tissue mechanical properties were analysed in the VTIQ examination. The pathologic diagnosis was established after surgery or in the follow-up examination for suspected benign lesions. Over 36 months, 22 focal testicular lesions (median lesion size, 18 mm; range, 4-36 mm in 20 patients (median age, 43 years; range, 22-81 years) were examined. Lesions were hyperechoic (n = 1), hypoechoic (n = 14), isoechoic (n = 1), of mixed echogenicity (n = 3) or anechoic (n = 3). Histological examination showed one benign lesion (6.25%) with a mean size of 7 mm and 15 malignant lesions (93.75%) with a mean size of 20 mm. Mean shear wave velocity for normal testicular tissue was 1.17 m/s. No shear wave velocity could be measured in cystic lesions. The rest of the benign lesions showed a mean shear wave velocity of 2.37 m/s. The value of the shear wave velocity in germ cell tumours showed a mean shear wave velocity of 1.94 m/s and for seminoma it showed a mean shear wave velocity of 2.42 m/s. VTIQ is a reliable new method for measuring qualitative and quantitative stiffness of testicular lesions and tissue. The qualitative shear-wave elastography features were highly reproducible and showed good diagnostic performance in unclear testicular lesions. The VTIQ technique is also useful in assessing small testicular nodules and pseudolesions.

Normal breast tissue stiffness measured by a new ultrasound technique: Virtual touch tissue imaging quantification (VTIQ)

ObjectiveTo evaluate normal breast tissue stiffness with virtual touch tissue imaging quantification (VTIQ) using prospectively collected data. Materials and MethodsB-mode ultrasound and VTIQ were performed in 132 breasts in 97 women. Mean values of VTIQ for parenchyma and fatty tissue were compared between those measured in healthy breasts and in the surrounding of histologically proven benign and malignant breast lesions. Moreover we reviewed VTIQ values according to breast density measured by the American College of Radiology (ACR) categories. In addition we analyzed re-test reliability of VTIQ. ResultsIn 132 breasts the mean VTIQ values in parenchyma were significantly higher than in fatty tissue (3.23m/s±0.74 versus 2.5m/s±0.61; p<0.0001). In healthy breasts as well as in the surrounding of a benign or malignant lesions the VTIQ values of parenchyma were similar (p=0.12). In fatty tissue, small differences between mean VTIQ values of 2.25m/s±0.51, 2.52m/s±0.48 and 2.65m/s±0.71 (p=0.01) in the respective groups were observed. The comparison of mean VTIQ values of parenchyma and fatty tissue in more and less dense breasts (ACR 1+2 versus ACR 3+4 breasts) also yielded no statistically significant difference. The re-test reliability of VTIQ assessed with three independent measurements was moderate (interclass-correlation of 0.52 (p<0.0001)). ConclusionVTIQ is a reliable method for measuring the stiffness of breast tissue. We propose standard values for healthy parenchyma and fatty tissues independent of the surrounding tissue or the ACR category.

Evaluation of cervical cancer detection with acoustic radiation force impulse ultrasound imaging

The aim of this study was to evaluate the application of acoustic radiation force impulse (ARFI) ultrasound imaging and its potential value in the characterization of cervical cancer. ARFI ultrasound imaging of the uterine cervix was performed in 58 patients with cervical cancer prior to surgery. The diagnosis of cervical cancer was confirmed by pathological results in each case. eSie Touch elastography imaging (EI), Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (VTQ; Siemens Medical Solutions, Mountain View, CA, USA) were used to qualitatively and quantitatively analyze the elasticity and hardness of lesions. For statistical analysis, the non-parametric Mann-Whitney U test and the Student’s u test were used to compare the elastic parameters and the results. EI showed that, compared with the surrounding cervical tissue, 72.41% (42 of 58) of the malignant lesions showed 4th or 5th grade images and 27.59% (16 of 58) had 3rd grade images. The EI images showed a significant difference between the malignant lesions and the surrounding normal tissues (P<0.001). VTI showed that compared with the surrounding cervical tissue, 84.48% (49 of 58) of the malignant lesions were stiffer than the surrounding tissues and 15.52% (9 of 58) had black and white honeycomb-like images. The VTI images showed a significant difference between the malignant lesions and normal cervical tissues (P<0.001). The surrounding normal tissues had lower VTQ values, with a mean of 2.11±1.19 m/sec, while the VTQ values in malignant lesions were higher than the surrounding normal tissues (3.41±1.59 m/sec, P<0.001). ARFI ultrasound imaging of the uterine cervix may be an objective method for the assessment of soft tissues. It has high sensitivity and specificity in the evaluation of cervical cancer and therefore has good diagnostic value in clinical applications.

Preliminary Study on the Diagnostic Value of Acoustic Radiation Force Impulse Technology for Differentiating Between Benign and Malignant Thyroid Nodules

This study aimed to evaluate the diagnostic value of acoustic radiation force impulse (ARFI) elasticity imaging for differentiating between benign and malignant thyroid lesions. Hospitalized patients needing thyroid surgery were evaluated. After routine thyroid sonography, the patients underwent ARFI elasticity imaging. Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (VTQ; Siemens Medical Solutions, Mountain View, CA) were used to qualitatively and quantitatively analyze the elasticity and hardness of nodules. For statistical analysis, the Student t test, analysis of variance, and the χ(2) test were used to compare the elastic parameters. Of the 98 thyroid nodules observed in 72 hospitalized patients, 56 were nodular goiters, 16 thyroid adenomas, 4 thyroiditis, and 22 thyroid malignancies, with mean VTQ values ± SD of 2.034 ± 0.484, 1.835 ± 0.364, 2.293 ± 0.787, and 3.941 ± 1.393 m/s, respectively. The elastic parameters of malignant nodules were significantly higher than those of benign nodules (P < .001) and the surrounding thyroid parenchyma (P < .001). There was no significant difference between the VTQ value of benign nodules and that of the surrounding normal thyroid parenchyma (P > .05). For differentiating between benign and malignant nodules, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accordance rate were 86.36%, 93.42%, 79.17%, 95.95%, and 91.84% based on the standard VTQ value (2.555m/s). In total, 77.6% (59 of 76) of the benign nodules showed softer and equal images in the VTI mode, and 77.3% (17 of 22) of the malignant nodules showed stiffer images (P < .001). Acoustic radiation force impulse imaging has high sensitivity and specificity in evaluating benign and malignant thyroid nodules and therefore had good diagnostic value in clinical applications.

Étude comparative de 23 chats infectés naturellement par Mycoplasma haemofelis et Candidatus Mycoplasma haemominutum : tableau clinique, modifications biologiques et réponse au traitement

Placental rigidity and biometry of twelve pregnant bitches were evaluated using B-mode and Acoustic Radiation Force Impulse (ARFI) ultrasonography, performed once daily, from day 15 of gestation until parturition. Specific software (Virtual Touch Tissue Quantification® VTTQ and Virtual Touch Tissue Imaging Quantification® VTTIQ) were used. Values for results for variables were correlated and regression models related to gestational day were used to make evaluations. Maternal-fetal placental thickness increased to day 63 (P < 0.0001; R² = 0.91); maternal placental thickness increased until day 40 (P = 0.0340; R² = 0.54); and fetal placental thickness increased to day 50 (P < 0.0001; R² = 0.83) of gestation. Shear wave velocity (SWV) of the dorsal (P < 0.0010) was greater than lateral, which in turn was greater (P = 0.020) than the ventral area. The SWV of the dorsal area as determined using VTTQ, decreased from day 21–35 and increased to day 56 of gestation (P = 0.0291; R² = 0.4021); lateral SWV decreased from day 24–45 and increased until the time of parturition (P < 0.001; R² = 0.6055). The SWV of the dorsal area, as determined using VTTIQ, decreased from day 21–43 and then increased to day 60 of gestation (P = 0.0016; R² = 0.5075); and ventral area SWV increased from day 21–23 and decreased until the time of parturition (P < 0.001; R² = 0.8055). Placental alterations reflect structural and biochemical gestational adaptations and can become useful techniques for obstetrics.