Shear wave elastography-based skin assessment system for systemic sclerosis: a supplement or alternative to conventional ultrasound?

Background: Although shear wave elastography (SWE) has been found to have the potential to evaluate skin lesions in systemic sclerosis (SSc), current research fails to answer the following questions: (I) can high-frequency ultrasound (HFUS) and SWE at multiple sites throughout the body distinguish SSc subtypes; (II) is HFUS and SWE at every site equally affected by clinical characteristics; and (III) is SWE a supplement or a choice to HFUS. This prospective study aimed to compare the value of SWE-based skin stiffness and HFUS-based skin thickness in distinguishing different SSc subtypes, verify the influence of clinical features on SWE and HFUS, and provide a basis for the screening of the optimal evaluation sites and indicators in the future. Methods: Forty-nine limited and 51 diffuse SSc patients were included in this study. Their skin was assessed at 17 sites by palpation using the modified Rodnan skin score (mRSS), skin thickness measured by HFUS, and skin stiffness by SWE. Clinical features, including age, sex, body mass index, and disease duration, were collected. Results: The diffuse SSc patients had higher skin stiffness at most sites (P<0.05), except for the finger, foot, and forehead, and a thicker skin layer at most sites (P<0.05), except for the finger. The area under the curve (AUC) of HFUS, SWE, and the combination of the two in distinguishing diffused and limited SSc were 0.866, 0.921, and 0.973, respectively. The differences were statistically significant (combination vs. SWE, P=0.002, combination vs. HFUS, P=0.021). Longer disease duration was associated with a thinner skin layer at the forearm, arm, chest wall, abdominal wall, and thigh in limited SSc, including the leg in diffused SSc. SWE was less affected by clinical features than HFUS. SWE could achieve greater discrimination between different mRSSs at multiple sites, such as fingers and arms, than HFUS. Conclusion: For the assessment of SSc skin, SWE has several advantages over HFUS, including less influence by clinical features and greater sensitivity to discriminate different mRSSs. SWE has the potential to become a primary imaging assessment tool as well as HFUS.

Preoperative Visualized Ultrasound Assessment of the Recurrent Laryngeal Nerve in Thyroid Cancer Surgery: Reliability and Risk Features by Imaging.

BACKGROUND: Preoperative identification and visualization of tumor infiltration of the recurrent laryngeal nerve (RLN) in patients with thyroid cancer is important. The purpose of our study was to evaluate the reliability and feasibility of preoperative assessment by ultrasound and to identify ultrasound imaging features potentially associated with tumor infiltration of the RLN. METHODS: In this prospective study, patients undergoing thyroid cancer surgery at our institution between August 2020 and January 2021 were included, and preoperative ultrasound visualization of the RLN and thyroid lesions was performed. RLN infiltration was also confirmed surgically in all cases. Five patients with enlarged lymph nodes were selected to undergo injection of carbon nanoparticles to confirm the correctness of RLN identification by preoperative ultrasound. The repeatability of RLN assessment by ultrasound was evaluated by comparing the correlation between pre- and intraoperative, intra- and inter-group assessments. Parameters of normal RLNs according to age, sex, and body mass index were established. Finally, ultrasound imaging features of patients with RLN tumor infiltration were analyzed to identify potential risk predictors. RESULTS: According to the ultrasonic assessment, RLNs of 70 patients appeared normal, while 14 of those patients appeared to be infiltrated by tumors. During surgery, the 70 cases of normal RLNs were confirmed, but only 8 of the 14 suspected cases of infiltration were confirmed. In all five patients injected with carbon nanoparticles, the location of RLNs adjacent to the marked lymph nodes observed by surgeons corresponded to the RLN location identified by preoperative ultrasound. The repeatability of RLN estimation varied from moderate to excellent. There were no significant differences in cross-sectional area, width, or thickness of normal RLNs according to age, sex, or body mass index. Indistinct margin with tumor, incontinuous shape as ultrasound features by the analysis of patients with surgically confirmed RLN infiltration were associated with tumor invasion. CONCLUSION: We show that preoperative ultrasound can be applied to visualize the RLN and may help predict tumor infiltration of the RLN.

Ultrasound assessment in psoriatic arthritis (PsA) and psoriasis vulgaris (non-PsA): which sites are most commonly involved and what features are more important in PsA?

BACKGROUND: The aim of this study was to find out the most commonly involved sites and the most important ultrasonic features in psoriatic arthritis (PsA). METHODS: In total, 120 PsA patients and 320 psoriasis vulgaris (non-PsA) patients were assessed by grayscale and power Doppler (PD) ultrasound (US). Joints, tendons, enthesis, and bursa changes were observed. Weights of affected anatomical sites of PsA patients (overall weights >90%) were calculated. Affected anatomical sites between PsA and non-PsA patients were compared. Ultrasonic features of joint, tendon, entheses, and bursa changes between PsA and non-PsA patients were also compared. Finally, the test performance of ultrasonic features for the diagnosis of PsA was calculated. RESULTS: The anatomical sites with the highest weights were the Achilles tendon, quadriceps tendon, and knee; weights of these anatomical sites were all more than 5%. Among the affected anatomical sites of PsA patients, most of the anatomical sites were more greatly affected in the PsA patients than in the non-PsA patients (all P<0.05). The comparison of the affected Achilles tendon, quadriceps tendon, MTP1, subacromial-subdeltoid bursa, MCP4, and MCP3 showed no significance between PsA and non-PsA patients (all P>0.05). Joint synovial thickening, joint PD signal grades, joint bone erosions, tendon sheath synovial thickening, tendon sheath PD signals, enthesis bone erosions, and enthesis PD signals in PsA patients were higher than in non-PsA patients (all P<0.05). Joint PD signal grades, joint bone erosions, enthesis bone erosions, and enthesis PD signals showed the highest specificities, which were 96.06%, 95.15%, 96.93%, and 94.63% respectively. CONCLUSIONS: The most common involvement sites of PsA were the Achilles tendon, quadriceps tendon, and knee, and some sites in non-PsA patients were also highly involved. The most important features in PsA included joint PD signal grades, joint bone erosion, entheses bone erosions, and entheses PD signals in US assessment.

Quantitative Assessment of Skin Stiffness Using Ultrasound Shear Wave Elastography in Systemic Sclerosis.

This study was aimed at investigating the performance of ultrasound shear wave elastography (US-SWE) in the assessment of skin (the dermis) stiffness in patients with systemic sclerosis (SSc). The thickness and elastic modulus of the skin were measured using US-SWE at 6 sites in 60 SSc patients and 60 healthy volunteers: the bilateral middle fingers and forearms and the anterior chest and abdomen. To evaluate clinical scores, the measurements were also extended to 17 skin sites in 30 patients. The diagnostic performance of US-SWE in the differentiation of SSc from healthy skin was determined by receiver operating characteristic (ROC) curve analysis, and the reliability of the measurement was evaluated with intra- and inter-class correlation coefficients. The results of US-SWE were compared with modified Rodnan skin thickness scores. Our results indicated that (i) the elastic modulus values were significantly higher in SSc patients than in controls, with or without normalization by skin thickness; (ii) receiver operating characteristic analysis revealed normalized US-SWE cutoff values with a very high accuracy for right and left fingers (areas under the curve = 0.974 and 0.949), followed by left forearm (0.841), anterior abdomen (0.797), right forearm (0.772) and anterior chest (0.726); (iii) the reliability of US-SWE measurements was good for all examined sites with intra-observer correlation coefficients of 0.845-0.996 and inter-observer correlation coefficients of 0.824-0.985; and (iv) total scores of skin involvement determined at 17 sites (modified Rodnan skin thickness scores) correlated with skin stiffness (r = 0.832) and thickness (r = 0.736). In conclusion, US-SWE is a quantitative method with high specificity, sensitivity and reliability in the detection of SSc involvement. This non-invasive, real-time and operator-independent imaging technique could be an ideal tool for the assessment of SSc disease.

[Quantitative Assessment of Skin Thickness using High Frequency Ultrasound in Systemic Sclerosis].

OBJECTIVE: To investigate the performance of high frequency ultrasound in the assessment of skin thickness in patients with systemic sclerosis (SSc). METHODS: The study included 82 SSc (SSc group) and 67 healthy volunteers (control group) from 2014 to 2016. The skin thickness at bilateral middle fingers and forearms,anterior chest and abdominal wall was measured using high frequency ultrasound. All the patients with SSc underwent the modified rodnan skin score (mRSS) over 17 anatomical sites by an experienced dermatologist. The differences in age,sex,height,body mass,body mass index (BMI) and skin thickness between SSc patients and healthy controls were compared. Receiver operating characteristic (ROC) curve analysis was performed to determine the performance of high frequency ultrasound in the differentiation of SSc from healthy skin,and the correlation of mRSS with skin thickness were analyzed. RESULTS: SSc patients and healthy controls shared similar demographic features (age,sex ratio,height,body mass,BMI) (P>0.05). Skin thickness values in SSc patients were increased significantly at fingers and forearms compared with healthy controls (P<0.05). The area under the curve (AUC) was 0.938, 0.905, 0.608, 0.586, 0.398, 0.321 at right and left finger,right and left forearm,chest and abdominal wall. Among them,AUC>0.9 of right and left fingers can be used for diagnosis,The skin thickness cut-off value for determining the diagnosis of SSc were as follows: 1.35 mm at the right finger with 84.1% sensitivity and 95.5% specificity,1.26 mm at the right forearm with 86.6% sensitivity and 89.6% specificity,respectively. Skin thickness increased significantly with mRSS. The correlation of total mRSS scores with total skin thickness was 0.599 (P<0.001),and the correlation of local mRSS score with local skin thickness were 0.400-0.623 (P<0.001),with the highest correlation coefficient at right finger and the lowest at abdomen. CONCLUSION: High frequency ultrasound may reflect extent of skin involvement of SSc,and skin thickness assessed with high frequency ultrasound appeared to be highly specific and sensitive at fingers.

Quantitative Assessment of Skin Stiffness in Localized Scleroderma Using Ultrasound Shear-Wave Elastography.

The purpose of this study was to evaluate the usefulness of ultrasound shear-wave elastography (US-SWE) in characterization of localized scleroderma (LS), as well as in the disease staging. A total of 21 patients with 37 LS lesions were enrolled in this study. The pathologic stage (edema, sclerosis or atrophy) of the lesions was characterized by pathologic examination. The skin elastic modulus (E-values including Emean, Emin, Emax and Esd) and thickness (h) was evaluated both in LS lesions and site-matched unaffected skin (normal controls) using US-SWE. The relative difference of E-values (ERD) was calculated between each pair of lesions and its normal control for comparison among different pathologic stages. Of the 37 LS lesions, 2 were in edema, 22 were in sclerosis and 13 were in atrophy. US-SWE results showed a significant increase of skin elastic modulus and thickness in all lesions (p < 0.001 in sclerosis and p < 0.05 in atrophy) compared with the normal controls. The measured skin elastic modulus and thickness were greater in sclerosis than in atrophy. However, once normalized by skin thickness, the atrophic lesions, which were on average thinner, appeared significantly stiffer than those of the sclerosis (normalized ERD: an increase of 316.3% in atrophy vs. 50.6% in sclerosis compared with the controls, p = 0.007). These findings suggest that US-SWE allows for quantitative evaluation of the skin stiffness of LS lesions in different stages; however, the E-values directly provided by the US-SWE system alone do not distinguish between the stages, and the normalization by skin thickness is necessary. This non-invasive, real-time imaging technique is an ideal tool for assessing and monitoring LS disease severity and progression.

Quantitative Assessment of Healthy Skin Elasticity: Reliability and Feasibility of Shear Wave Elastography.

The goal of this study was to investigate the reliability and feasibility of shear wave elastography by assessing the elasticity of the healthy skin of 40 volunteers. Young's moduli for bilateral fingers, forearms, anterior chest (sternum), and anterior abdomen were determined with both transverse and longitudinal sectional measurements. Reliability of measurements was evaluated using intra- and inter-class correlation coefficients with two observers. Our results revealed that the elastic modulus values of the skin between symmetric parts of fingers and forearms did not statistically different. No differences were found between the transverse and longitudinal sections of forearms, anterior chest, and abdomen (p > 0.05), except for middle fingers (p = 0.004). Inter-observer and intra-observer repeatability (inter- and intra-class correlation coefficients) varied from moderate to excellent depending on the skin site (0.62-0.91). In conclusion, shear wave elastography reached a good consistency in measuring healthy skin elasticity. Further studies are needed to provide more information on the factors that influence the reliability of shear wave elastography measurements in both healthy and diseased skin.

Epidemiological survey on newborns born at the obstetric departments in hospitals in mid-southern region of China in 2005.

OBJECTIVE: To investigate the situations at birth of newborns in the mid-southern region of China by performing a survey on the newborns born at urban hospitals. METHODS: A total of 23 hospitals in the mid-southern region of China were selected to participate in this survey. The data of 15,582 newborns who were born at the obstetric departments from January 1, 2005 to December 31, 2005 were retrospectively investigated. RESULTS: The male to female ratio among newborns was 1.16:1. The incidence of preterm birth was 8.11%, while very low birth weight (VLBW) infants accounted for 0.73%. The rates of spontaneous vaginal delivery and cesarean section ware 57.52% and 40.82%, respectively, while the other delivery modes accounted for 1.66%. The incidence of neonatal asphyxia was 3.78% (0.75% for heavy asphyxia). The mortality of newborns was 0.55% (5.56% for preterm infants). CONCLUSIONS: The incidences of preterm birth and neonatal asphyxia are relatively high in the mid-southern region of China. The rate of cesarean section is abnormally high, which is due mainly to social factors.

A survey of neonatal births in the maternal departments in urban China 2005.

OBJECTIVE: The authors studied the epidemiology of births in urban China. STUDY DESIGN: The authors conducted a retrospective study using data from the perinatal dataset of women delivering live births in 2005 at the maternity departments of 72 hospitals from 47 urban areas of 22 provinces in China. RESULTS: A total of 45,722 infants born from Jan 1, 2005 to Dec 31, 2005 were enrolled. (I) Male to female ratio was 1.13:1; (II) 8.1% of infants were born preterm; (III) The incidence of very low birth weight infants was 0.7%; (IV) A total of 99.7% of women delivering at term were naturally conceived and 0.3% had experienced assisted reproduction. Whereas 1.6% in women delivering preterm had assisted reproductive; (V) The total cesarean delivery rate was 49.2% compared to 50.8% of vaginal birth. Most cesarean delivery (38.1%) were due to social factors; (VI) Overall, 4.8% of infants had an Apgar of less than 7 at 1 minute, 1.6% less than 7 at 5 minutes; (VII) Of all the infants, 7.14% were admitted to neonatal units and death rate was 0.74% in all infants. CONCLUSIONS: The proportion of preterm births was still higher in 2005 than that in 2002 and total caesarian delivery rate was much higher in urban China than that in America as well as most Asia countries.