Sonographic evaluation of pediatric localized scleroderma: preliminary disease assessment measures

Non-invasive imaging and clinical skin scores in juvenile localized scleroderma

OBJECTIVES

To evaluate whether in juvenile localized scleroderma (JLS), non-invasive imaging can differentiate affected from non-affected skin and whether imaging correlates with a validated skin score [Localised Scleroderma Cutaneous Assessment Tool (LoSCAT)].

METHODS

A total of 25 children with JLS were recruited into a prospective study and a single 'target' lesion was selected. High-frequency ultrasound (HFUS, measuring skin thickness), infrared thermography (IRT, skin temperature), laser Doppler imaging (LDI, skin blood flow) and multispectral imaging (MSI, oxygenation) were performed at four sites: two of affected skin (centre and inner edge of lesion) and two of non-affected skin (1 cm from the edge of the lesion 'outer' and contralateral non-affected side) at four visits at 3 month intervals.

RESULTS

Differences between affected and non-affected skin were detected with all four techniques. Compared with non-affected skin, affected skin was thinner (P < 0.001), with higher temperature (P < 0.001-0.006), perfusion (P < 0.001-0.039) and oxygenation (P < 0.001-0.028). Lesion skin activity (LoSCAT) was positively correlated with centre HFUS [r = 0.32 (95% CI 0.02, 0.61), P = 0.036] and negatively correlated with centre LDI [r = -0.26 (95% CI -0.49, -0.04), P = 0.022]. Lesion skin damage was positively correlated with centre and inner IRT [r = 0.43 (95% CI 0.19, 0.67), P < 0.001 and r = 0.36 (95% CI 0.12, 0.59), P = 0.003, respectively] and with centre and inner LDI [r = 0.37 (95% CI 0.05, 0.69), P = 0.024 and r = 0.41 (95% CI 0.08, 0.74), P = 0.015, respectively].

CONCLUSION

Non-invasive imaging can detect differences between affected and non-affected skin in JLS and may help to differentiate between activity (thicker, less well-perfused skin) and damage (thinner, highly perfused skin).

Color Doppler Ultrasound Assessment of Subclinical Activity With Scoring of Morphea

BACKGROUND

Detection of activity in morphea is paramount for adequately managing the disease. Subclinical ultrasound involvement on inactive lesions or healthy skin areas adjacent to morphea has not been described to date.

OBJECTIVES

The study aimed to detect morphea's subclinical activity by Color Doppler ultrasound not identified with the clinical scorings.

MATERIALS & METHODS

This cross-sectional retrospective study was done from January 2014 to July 2019 in patients with a clinicopathological diagnosis of morphea. The modified Localized Scleroderma Skin Severity Index (mLoSSI) and The Ultrasound Morphea Activity Score (US-MAS) were used to correlate clinical and subclinical activity.

RESULTS

A total of 36 patients met the inclusion criteria. 54% of cases presented subclinical activity in areas adjacent to the clinically active lesion, 23% in nonadjacent regions, and 23% demonstrated activity at a clinically inactive lesion site.100% of patients with morphea "en coup de sabre" involving the frontal region of the face concomitantly presented both subclinical activities of morphea on the frontal facial region and the scalp following the same axis.A positive relationship was observed between the degree of clinical activity measured by mLoSSI and US-MAS scoring.The main limitations of our study were the low number of patients and the inability to detect alterations < 0.1 mm.

CONCLUSIONS

Subclinical activity is frequent in morphea, can extend beyond the lesional areas, including apparently noninvolved adjacent and distant corporal regions, and can be detected by color Doppler ultrasound.

Ultrasonography in Pediatric Rheumatology

This review highlights the increasing evidence from the last few years supporting the use of musculoskeletal ultrasonography (MSUS) in the evaluation and management of patients with pediatric rheumatic diseases, particularly focusing on juvenile idiopathic arthritis. Recently developed definitions for the sonographic appearance of healthy and pathologic joints in children are discussed. Further topics explored include how MSUS enhances the diagnosis of inflammatory joint disease (synovitis, enthesitis, tenosynovitis), including the detection of subclinical synovitis. There is a brief summary on the use of ultrasonography in the evaluations of myositis, Sjögren syndrome, and scleroderma.

Feasibility of Using Elastography Ultrasound in Pediatric Localized Scleroderma (Morphea)

Assessment and monitoring of inflammation and tissue damage is crucial in localized scleroderma (LS), but validated diagnostic tools are lacking. We aimed to determine the feasibility of using acoustic radiation force imaging ultrasound elastography in the assessment of pediatric-onset LS lesions. Conventional ultrasound and shear-wave elastography (SWE) imaging were used to characterize changes in pre-assigned LS lesions in 13 prospectively recruited participants. Contralateral sites were used as controls. Mean SWE values were compared. LS lesions were significantly stiffer than control sites in the dermis and the hypodermis using both parametric and non-parametric tests, before and after skin-thickness normalization. We show that SWE imaging is a feasible way to discriminate between normal skin and LS lesions in the pediatric population.

Connective Tissue Disorders in Childhood: Are They All the Same?

Systemic connective tissue disorders are characterized by the presence of autoantibodies and multiorgan system involvement. Juvenile systemic lupus erythematosus with or without associated antiphospholipid syndrome; juvenile dermatomyositis; sclerodermiform syndromes, including systemic and localized sclerodermas and eosinophilic fasciitis; mixed connective tissue disease; and Sjögren syndrome are the disorders that affect children most frequently. Diagnosis is difficult, because the clinical presentation of patients is diverse, from mild to severe disease. In addition, all organs may be affected. However, a variety of imaging techniques are now available to investigate rheumatic disease in children. These imaging modalities offer the potential for earlier diagnosis and improved assessment of therapeutic response. This article reviews the main connective tissue disorders that affect children, highlighting their key imaging features on images acquired with different diagnostic imaging modalities and correlating these features with clinical and pathologic findings, when available. ^©RSNA, 2019.

Current status and recent advances on the use of ultrasonography in pediatric rheumatic diseases

BACKGROUND

Ultrasonography has become a useful tool in the clinical rheumatology settings in the last two decades, but its use has only recently been explored by pediatric rheumatologists. The aim of this article is to review the literature on the current status and recent advances on the use of ultrasound in pediatric rheumatic diseases.

DATA SOURCES

We have retrieved and reviewed the relevant articles from MEDLINE/PubMed databases published so far, on the applications of ultrasound in juvenile idiopathic arthritis (JIA), systemic lupus erythematosus, dermatomyositis, enthesitis, Sjogren's syndrome, and other rheumatic diseases. In addition, articles on novel ultrasound imaging technology of potential use in pediatric rheumatology are also reviewed.

RESULTS

In JIA, ultrasound can be used to detect subclinical synovitis, to improve the classification of patients in JIA subtypes, to capture early articular damage, to monitor treatment response, and to guide intraarticular injections. Ultrasound is also considered useful in other rheumatic disorders for the evaluation of musculoskeletal symptoms, assessment of parotid gland pathology, and measurement of skin thickness and pathology. Novel ultrasound techniques developed to augment the functionality of ultrasonography may also be applicable in pediatric rheumatic disorders.

CONCLUSIONS

Ultrasound shows great promise in the assessment and management of children with rheumatologic disorders. However, standardization and validation of ultrasound in healthy children and in patients with rheumatic diseases are still needed.

Cutaneous ultrasound and its utility in pediatric dermatology. Part I: Lumps, bumps, and inflammatory conditions

High-frequency ultrasonography represents a promising tool for pediatric dermatologists. It is a non-invasive diagnostic technique that is particularly appealing when working with children. It can be easily performed at the patient's bedside, avoiding diagnostic delays, sedation, or multiple visits. It represents a useful adjunct to clinical examination and can enhance our understanding of cutaneous diseases. Patient cooperation and limited training and experience are the main challenges for cutaneous ultrasonography in pediatric dermatology. This review describes cutaneous ultrasonography and the nuances of its use in the pediatric setting, followed by the ultrasonographic findings of cutaneous lumps, bumps, and inflammatory dermatoses commonly encountered in pediatric patients.

Imaging molecular signatures for clinical detection of scleroderma in the hand by multispectral photoacoustic elastic tomography

Scleroderma (SD) is a rare autoimmune disease, which is divided into 2 categories: the localized SD and systemic SD. The localized SD mainly causes skin thickening of the fingers, whereas the systemic SD can further affect the blood vessels and internal organs. In this pilot study, the multispectral photoacoustic elastic tomography (PAET) imaging technique was used to recover the quantitative physiological and elastic properties of biological tissues for the diagnosis of SD. Three healthy subjects and 3 SD patients were recruited and clinically examined by a rheumatologist, and then their hand/fingers were scanned by both magnetic resonance imaging and our home-made photoacoustic imaging system. Physiological parameters including oxygen saturation (S_T O₂ ), deoxy-hemoglobin (Hb) and oxy-hemoglobin (HbO₂ ) concentrations and mechanical properties such as bulk elastic modulus images were reconstructed using the developed PAET reconstruction method. Our imaging results demonstrated that the physiological and elastic parameters exhibit striking differences between the SD and normal fingers, indicating that these biomarkers can serve as molecular signatures for early detection of SD. These quantitative physiological properties and bulk modulus may also pave a new path for improved understanding the pathological mechanism of SD.

Imaging findings in systemic childhood diseases presenting with dermatologic manifestations

PURPOSE

Many childhood diseases often present with skin abnormalities with which radiologists are largely unfamiliar. Knowledge of associated dermatologic manifestations may aid the radiologist in confirming the diagnosis and recommending targeted imaging of affected organs.

METHODS

We review the imaging findings in childhood diseases associated with dermatologic manifestations.

FINDINGS

Diseases include dermatologic findings which herald underlying malignancy (Neuroblastoma, leukemia/lymphoma, Langerhans cell histiocytosis),are associated with risk of malignancy (Epidermolysis Bullosa, basal cell nevus syndrome, Cowden's syndrome, Tuberous Sclerosis),or indicate a systemic inflammatory/immune disorder (Kawasaki's disease, Henoch Schonlein Purpura, systemic lupus erythematosus, scleroderma, sarcoidosis, dermatomyositis and immune thrombocytopenic purpura).

CONCLUSION

Familiarity with pertinent findings in childhood diseases presenting with dermatologic manifestations in childhood diseases aids the radiologist in confirming the diagnosis and guiding imaging workup.

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 E_mean, E_min, E_max and E_sd) 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 (E_RD) 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 E_RD: 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.

Musculoskeletal MRI findings of juvenile localized scleroderma

BACKGROUND

Juvenile localized scleroderma comprises a group of autoimmune conditions often characterized clinically by an area of skin hardening. In addition to superficial changes in the skin and subcutaneous tissues, juvenile localized scleroderma may involve the deep soft tissues, bones and joints, possibly resulting in functional impairment and pain in addition to cosmetic changes.

OBJECTIVE

There is literature documenting the spectrum of findings for deep involvement of localized scleroderma (fascia, muscles, tendons, bones and joints) in adults, but there is limited literature for the condition in children. We aimed to document the spectrum of musculoskeletal magnetic resonance imaging (MRI) findings of both superficial and deep juvenile localized scleroderma involvement in children and to evaluate the utility of various MRI sequences for detecting those findings.

MATERIALS AND METHODS

Two radiologists retrospectively evaluated 20 MRI studies of the extremities in 14 children with juvenile localized scleroderma. Each imaging sequence was also given a subjective score of 0 (not useful), 1 (somewhat useful) or 2 (most useful for detecting the findings).

RESULTS

Deep tissue involvement was detected in 65% of the imaged extremities. Fascial thickening and enhancement were seen in 50% of imaged extremities. Axial T1, axial T1 fat-suppressed (FS) contrast-enhanced and axial fluid-sensitive sequences were rated most useful.

CONCLUSION

Fascial thickening and enhancement were the most commonly encountered deep tissue findings in extremity MRIs of children with juvenile localized scleroderma. Because abnormalities of the skin, subcutaneous tissues and fascia tend to run longitudinally in an affected limb, axial T1, axial fluid-sensitive and axial T1-FS contrast-enhanced sequences should be included in the imaging protocol.

Evaluation of the efficacy and safety of topical imiquimod 5% for plaque-type morphea: a multicenter, prospective, vehicle-controlled trial

BACKGROUND

There is currently a lack of evidence-based therapies that are safe and effective for plaque-type morphea. We aimed to evaluate the therapeutic potential and safety profile of imiquimod 5% cream in plaque-type morphea.

METHODS

We enrolled 25 adult patients from two Canadian centers with histologically confirmed plaque-type morphea. Imiquimod 5% was applied to a representative plaque, and vehicle was applied to a control plaque for 9 months. Treatment efficacy was assessed with the Dyspigmentation, Induration, Erythema, and Telangiectasias (DIET) score, histology, and ultrasound evaluation.

RESULTS AND CONCLUSIONS

Twenty-two patients completed the entire length of the study. Imiquimod 5% was superior to vehicle in reducing DIET scores at 3, 6, 9, and 12 months (p < .05). Induration demonstrated the greatest response. Histologic evaluation showed significant improvement or resolution of disease. However, no ultrasonographic differences were found in dermal and hypodermal thicknesses between the treatment and vehicle groups (p > .05). Adverse effects were minimal and well tolerated.

A cross-sectional electromyography assessment in linear scleroderma patients

BACKGROUND

Muscle atrophy and asymmetric extremity growth is a common feature of linear scleroderma (LS). Extra-cutaneous features are also common and primary neurologic involvement, with sympathetic dysfunction, may have a pathogenic role in subcutaneous and muscle atrophy. The aim was investigate nerve conduction and muscle involvement by electromyography in pediatric patients with LS.

METHODS

We conducted a retrospective review of LS pediatric patients who had regular follow up at a single pediatric center from 1997-2013. We selected participants if they had consistently good follow up and enrolled consecutive patients in the study. We examined LS photos as well as clinical, serological and imaging findings. Electromyograms (EMG) were performed with bilateral symmetric technique, using surface and needle electrodes, comparing the affected side with the contralateral side. Abnormal muscle activity was categorized as a myopathic or neurogenic pattern.

RESULTS

Nine LS subjects were selected for EMG, 2 with Parry-Romberg/Hemifacial Atrophy Syndrome, 7 linear scleroderma of an extremity and 2 with mixed forms (linear and morphea). Electromyogram analysis indicated that all but one had asymmetric myopathic pattern in muscles underlying the linear streaks. Motor and sensory nerve conduction was also evaluated in upper and lower limbs and one presented a neurogenic pattern. Masticatory muscle testing showed a myopathic pattern in the atrophic face of 2 cases with head and face involvement.

CONCLUSION

In our small series of LS patients, we found a surprising amount of muscle dysfunction by EMG. The muscle involvement may be possibly related to a secondary peripheral nerve involvement due to LS inflammation and fibrosis. Further collaborative studies to confirm these findings are needed.

Ultrasonographic evaluation of oral submucous fibrosis in habitual areca nut chewers

OBJECTIVES

To characterize the sonographic features of the buccal mucosa in patients with oral submucous fibrosis (OSF).

METHODS

Three groups (controls with areca-related habits, controls without areca-related habits and clinically diagnosed OSF cases), each comprising 30 subjects, were included in the study. After a thorough clinical examination, transcutaneous B-mode ultrasonography was performed with a multifrequency linear transducer (5-10 MHz) for anterior and posterior buccal mucosa bilaterally. Both clinical and ultrasound findings were recorded by three independent observers. One-way analysis of variance and Tukey's honestly significant difference post-hoc tests were used for statistical comparisons between groups and Pearson χ(2) tests to compare the proportions. Kappa statistics was used to determine the interobserver agreement.

RESULTS

The submucosa that appeared hypoechoic in the control groups had significantly increased echogenicity in the case group (hypo- to isoechoic in 46.7% and isoechoic in 53.3%). The differentiation between the submucosa and the muscle layer appeared distinct in the control groups while it was not clear in the case group (indistinct in 50% and completely lost in 50%). The number of sites found positive on the ultrasound was significantly greater than the number of clinically positive sites. There was a very good interobserver consistency in clinical and ultrasound findings.

CONCLUSIONS

Ultrasonography of the buccal mucosa demonstrates increased submucosal echogenicity and reduced echo differentiation between submucosa and muscle layer in OSF cases. Hence, it can be used as a non-invasive imaging modality to assess the disease extent and severity across the entire buccal mucosa to supplement clinical evaluation.