Measurement of Spleen Stiffness by Shear-Wave Elastography for Prediction of Splenomegaly Etiology

Evaluation of liver and spleen stiffness measurement with shear wave elastography in brucellosis

BACKGROUND

Human brucellosis, which is endemic in the eastern region of Turkey, infects the reticulo-endothelial system. Acute brucellosis may cause hepatomegaly or splenomegaly.

AIMS

The main purpose of this study was to investigate the effectiveness of the point shear wave elastography (pSWE) method in identifying and detecting liver and spleen stiffness in acute brucellosis.

METHODS

This case-control study included 40 patients with acute brusellosis and 60 healthy individuals as a control group. The demographic data, abdominal ultrasonography (USG) and pSWE results of the patient and control groups were evaluated. Statistical and ROC analyses were performed.

RESULTS

The liver pSWE value was 3.8395 ± 1.171 kPa in the patient group and 1.6619 ± 0.495 kPa in the control group. The spleen pSWE value was 3.2431 ± 1.803 kPa in the patient group and 1.3793 ± 0.622 kPa in the control group. The mean liver and spleen pSWE values were statistically significantly higher in the patient group than in the control group (p < 0.001). Cut-off values were determined as 2.524 for the liver pSWE and 1.62667 for the spleen pSWE. From the AUC values (0.959, 0.903), the diagnostic performance of liver and spleen pSWE values were seen to be excellent in distinguishing between patient and control groups.

CONCLUSIONS

The study results showed that liver and spleen stiffness were high in acute brucellosis patients and had predictive significance above certain cut-off values. It can be considered that pSWE, which evaluates liver and spleen stiffness in acute brucellosis, may provide diagnostic benefit as a reliable, non-invasive technique.

Shear Wave Ultrasonographic Elastography in Pediatric Spleens and Its Role in Differential Diagnosis

Shear wave elastography (SWE) has become popular in clinical practice for many diseases. However, there is not adequate research on spleen-related diseases. This study aimed to investigate the potential of quantitative values obtained through SWE in evaluating spleen pathologies in the pediatric population and to demonstrate its performance to differentiate splenomegaly-related diseases. The research group retrospectively included children with pathological diagnoses related to the spleen from November 2016 to April 2021, and they were categorized into three groups, including portal hypertension (PH), benign lymphoid hyperplasia (BLH), and malignant infiltration (MI). Spleen sizes and parenchymal stiffness were also calculated for each group. Subsequently, mean spleen stiffness in each group was compared with normal values within the same age group. In total, 2781 children (1379 children for the study group; 1402 children for the control group) were enrolled in the study. The highest stiffness was observed in the PH group, which is statistically higher than others (p < 0.05). Although the mean spleen stiffness in the group with BLH was higher than the control and MI group, the difference was not statistically significant (p = 0.08). The mean stiffness in the group with MI was significantly lower than both the control group (p = 0.005) and PH (p = 0.01). In conclusion, using SWE in the differential diagnosis of etiologies causing splenomegaly could make an important contribution.

Acoustic Radiation Force Impulse (ARFI) Elastography of Focal Splenic Lesions: Feasibility and Diagnostic Potential

PURPOSE

Nontraumatic focal splenic lesions (FSL) are rare, and the need for tissue diagnosis must be weighed against the very high risk of bleeding after a splenic biopsy. The aim of this study was to explore the feasibility and diagnostic potential of acoustic radiation force impulse (ARFI) elastography as a noninvasive method for different benign and malignant FSLs. No human studies on the elastographic characteristics of FSL exist.

METHODS

This was a retrospective analysis of 34 patients with FSLs, who underwent abdominal B-mode ultrasound (B-US), contrast-enhanced ultrasound (CEUS), and standardized ARFI examinations between October 2021 and December 2022 at our university hospital. The inclusion criteria were: (i) FSL size ≥ 1 cm; (ii) 10 valid ARFI measurements of the FSL, as well as of the normal splenic parenchyma (NSP) as an in vivo reference; and (iii) diagnostic confirmation of FSL etiology based on histological examination (8/34; 23.5%) or clinical evaluation, which included a clinical and sonographic follow-up (FU), CEUS morphology, and/or morphology on cross-sectional imaging (26/34; 76.5%). CEUS was performed on all patients and the FSLs were classified according to the current guidelines; cross-sectional imaging was available for 29/34 (85.3%). The mean FU duration was 25.8 ± 30.5 months. The mean ARFI velocity (MAV) of the FSL (MAVL), the NSP (MAVP), and the ratio of the MAVL to the MAVP (MAVL/P) were calculated and compared.

RESULTS

Of the 34 FSLs, 13 (38.2%) were malignant (mFSL) and 21 (61.8%) were benign (bFSL). The MAVL of all 34 FSLs (2.74 ± 0.71 m/s) was lower than the MAVP (3.20 ± 0.59 m/s), p = 0.009, with a mean MAVL/P ratio of 0.90 ± 0.34. No significant differences in the MAVL were observed between the mFSL (2.66 ± 0.67 m/s) and bFSL (2.79 ± 0.75 m/s). There were also no significant differences between the MAVP in patients with mFSL (3.24 ± 0.68 m/s) as compared to that in the patients with bFSL (3.18 ± 0.55 m/s). Likewise, the MAV L/P ratio did not differ between the mFSL (0.90 ± 0.41 m/s) and bFSL (0.90 ± 0.30 m/s) groups.

CONCLUSION

ARFI elastography is feasible in evaluating the stiffness of FSLs. The lesions' stiffness was lower than that of the NSP, regardless of the FSL etiology. However, differentiation between benign and malignant FSL with the help of this elastographic method does not appear possible. Larger prospective studies are needed to validate these findings.

Accuracy of B-mode ultrasound and ARFI elastography in predicting malignancy of canine splenic lesions

The objective was to evaluate the accuracy of B-mode ultrasonography and ARFI elastography in detecting malignancy in canine splenic lesions. Thirty-seven spleens with abnormalities (16 benign and 21 malignant) from dogs of different breeds and ages were evaluated. Echogenicity, echotexture, organ length and height were evaluated using B-mode. By ARFI elastography, tissue stiffness was evaluated qualitatively (elastogram) and quantitatively (measuring the shear wave velocity-SWV). Lesions were classified as diffuse, focal or multifocal (cranial, medial or caudal portion) and comparisons of the SWV between the injured and non-injured areas were performed. In the B-mode, no features were associated to malignancy (P > 0.05). In the elastogram, 35 spleens were non-deformable and 2 deformable, having no association with malignancy. The greater SWV was observed in malignant lesions (3.4 ± 0.6 m/s), followed by areas free from alterations (2.1 ± 0.3 m/s) and benign lesions (1.7 ± 0.5 m/s), with difference between groups (P < 0.0001). It was found that a SWV > 2.6 m/s indicates malignancy of canine splenic lesions (sensitivity of 95%, specificity of 100%, PPV of 100%, NPV of 94% and accuracy of 97%), concluding that ARFI elastography is a promising technique for differentiating malignancy in these lesions.

WFUMB Position Paper-Incidental Findings, How to Manage: Spleen

The World Federation for Ultrasound in Medicine and Biology (WFUMB) is addressing the issue of incidental findings (IFs) with a series of publications entitled "Incidental Imaging Findings-The Role of Medical Ultrasound." IFs are less commonly encountered in the spleen than in many other abdominal organs but remain a frequent dilemma in clinical practice. A histological diagnosis is rarely necessary for patient management. Many IFs, such as secondary spleens and splenic cysts, are harmless and do not require any further investigation. The diagnosis of many other focal splenic lesions is, however, often problematic. The following overview is intended to illustrate a variety of incidentally detected spleen pathologies such as size variants, shape variants, secondary spleens, focal splenic lesions and splenic calcifications. It should aid the examiner in establishing the diagnosis. Moreover, it should help the ultrasound practitioner decide which pathologies need no further investigation, those requiring interval imaging and cases in which immediate further diagnostic procedures are required.

Spleen Stiffness Measurement by Using Shear-Wave Elastography as a Predictor of Progression to Secondary Myelofibrosis

OBJECTIVE

Polycythemia vera (PV) and essential thrombocythemia (ET) are chronic myeloproliferative diseases that can transform to secondary myelofibrosis (SMF). In this study, we evaluated spleen stiffness using shear-wave elastography (SWE) as a predictor of progression to SMF.

METHODS

Participants were grouped as healthy volunteers (HVs), PV/ET patients, and SMF patients. Participants' spleen sizes, spleen stiffness values, bone marrow fibrosis degrees, and the other parameters were evaluated. Spleen stiffness values and spleen sizes were compared between groups.

RESULTS

Of the 121 participants included in this study, 52 patients were HVs, 52 patients were PV and/or ET patients, and 17 patients were SMF patients. In terms of age and sex, there was no difference between groups. Splenic parenchymal stiffness median values by using SWE were found to be 0.82 m/s in HVs, 1.41 m/s in PV/ET patients, and 2.32 m/s in SMF patients (P < 0.001). In terms of median length of the spleen, the difference between groups was significant (P < 0.001). In addition, we found a significant positive correlation between spleen stiffness and bone marrow fibrosis degree (P < 0.001, r = 0.757). However, in multivariate analysis, there was no strong independent risk factor for spleen stiffness.

CONCLUSION

In this study, we showed that measurement of spleen stiffness using SWE can distinguish SMF from PV/ET patients and HVs. Therefore, we believe that SWE may be used as a noninvasive and easily accessible method to check the fibrotic progression of bone marrow in PV and ET patients to monitor the transformation to SMF, and enables to detect fibrosis in early phase.

Efficacy of Shear Wave Elastography in the Differentiation of Acute and Subacute Deep Venous Thrombosis

ABSTRACT

It is important to know the age of clot formation to determine an appropriate treatment for deep vein thrombosis (DVT). The present study aims to differentiate between acute and subacute DVT using the shear wave elastography (SWE) technique. Patients with complaints no longer than 4 weeks and who were found to have early-stage (acute-subacute) thrombus on ultrasound (US) between January 2020 and May 2020 were included in the study. All of the patients underwent SWE using a Philips Healthcare EPIQ 5 Ultrasound System Inc. device with a high-resolution linear US probe (eL18-4, 22-2 MHz). Included in the study were 50 patients, including 23 with acute DVT and 27 with subacute DVT. Of the patients, 22 were women and 28 were men, and the mean age was 46.32 ± 11.33 years (range: 24-74 years). The mean SWE value was 2.63± 0.16 (2.39-2.96) in patients with acute DVT and 3.34± 0.31 (2.65-3.88) in patients with subacute DVT. The findings were statistically significant in the comparison of the 2 groups using an independent samples t test (P < 0.001). In the receiver operating characteristic analysis, the area under the curve was found to be 97.6%. When the cutoff value was taken as 2.85 according to the area under the curve, sensitivity was found to be 96.3%, and specificity was 91.3%. Thrombus stage plays a critical role in treatment decisions in DVT in the lower extremities. The present study reveals that the shear wave US elastography technique can be used to discriminate between acute and subacute DVT.

Spleen stiffness measurement by shear wave elastography using acoustic radiation force impulse in predicting the etiology of splenomegaly

PURPOSE

To measure spleen stiffness by shear wave elastography (SWE) using acoustic radiation force impulse (ARFI) in patients with splenomegaly and to evaluate utility of elastography technique in identifying etiology of splenomegaly.

METHODS

Sixty-one treatment-naïve patients with splenomegaly were enrolled. The control group consisted of 20 healthy subjects without history of any disease including diabetes and hypertension, alcohol consumption, or biochemical or ultrasonographic findings indicating hepatic and renal diseases. B-mode ultrasonography and elastographic examinations were performed by a radiologist blinded to the participants. Spleen stiffness was measured by SWE using ARFI. Shear wave velocity (SWV) values were given in m/s.

RESULTS

Splenomegaly patients were assigned into three groups according to their etiologies as hepatoportal (n = 21), myeloproliferative (n = 23), and infectious (n = 17). Splenomegaly groups and control group were comparable regarding age and sex. Spleen size was higher in the splenomegaly groups than in the controls. Median SWV was significantly higher in the hepatoportal (3.85 m/s) and myeloproliferative (3.42 m/s) groups than in the infectious (2.66 m/s) and control (2.22 m/s) groups. The correlation between SWV and spleen size was not significant in any of the groups. The cut-off value was 3.42 (sensitivity 80.9%, specificity 56.5%) in distinguishing hepatoportal from myeloproliferative etiology; 3.02 (sensitivity 100%, specificity 100%) in distinguishing hepatoportal from infectious etiology; and 2.84 (sensitivity 91.3%, specificity 88.2%) in distinguishing myeloproliferative from infectious etiology.

CONCLUSION

Spleen stiffness measured by elastographic techniques in splenomegaly patients was higher than that in healthy subjects. SWV appeared to be beneficial in predicting the etiology of splenomegaly.

Comparison of Efficiencies Between Shear Wave Elastography, Fine-Needle Aspiration Biopsy and American College of Radiology Thyroid Imaging Reporting and Data System Scoring System in Determining the Malignity Potential of Solid Thyroid Nodules

ABSTRACT

We aimed to evaluate the efficiencies of quantitative shear-wave elastography, fine-needle aspiration (FNA) biopsy and American College of Radiology (ACR)-thyroid imaging reporting and data system (TIRADS) scoring system in determining the malignity potential of solid thyroid nodules. In period between September 2014 and January 2016, 191 solid thyroid nodules of 189 patients were enrolled in this study. The mean shear wave velocities of the nodules were recorded by acoustic radiation force impulse method. All nodules were classified according to ACR-TIRADS scoring system and underwent FNA procedure. The cytopathologic results (after FNA) were benign in nature, atypical-cytology/suspiciously malign and highly suspicious of malignity in 117, 28, and 21 nodules, respectively. The specimen from FNA was insufficient in 25 nodules. Thirty-four nodules of 33 enrolled patients were operated, and the efficiencies of shear wave elastography, FNA, and ACR-TIRADS procedures were statistically analyzed; relying on the histopathologic results, the shear-wave elastography had 83.3% sensitivity, 93.7% specificity (with a cutoff value of 2,74 m/s), the FNA had 94.4% sensitivity, 87.5% specificity, and ACR-TIRADS had 88.2% sensitivity, 94.1 specificity in determining malignant tyroid nodules (P < 0.005). Quantitative shear wave elastography is concluded to be an effective, noninvasive, and practical imaging modality with a lesser sensitivity and specificity values than TIRADS unless a lower sensitivity but a higher specificity values than FNA (93.7% vs 87.5%) in considering the malignity potential of solid thyroid nodules.