Ultrasonographic imaging of systemic sclerosis digital ulcers: A systematic literature review and validation steps

Recent advances in non-invasive imaging of systemic sclerosis-related digital ulcers

Digital ulcers are a major source of pain and disability in patients with systemic sclerosis. Current treatments are not ideal, yet drug development for digital ulcers is hampered by a lack of objective outcome measures to facilitate clinical trials. Advances in non-invasive imaging could provide a way forward. This review article first describes the rationale for non-invasive imaging of digital ulcers in both clinical practice and research. In clinical practice, magnetic resonance imaging allows early diagnosis of underlying osteomyelitis, and smartphone imaging allows early (remote) identification of digital ulcers. In research, non-invasive imaging provides new insights into pathophysiology, as well as the ability to measure precisely digital ulcer surface area and volume. The imaging techniques discussed include mobile phone photography, ultrasound, laser Doppler methods and emerging technologies (multispectral imaging and polarisation-sensitive optical coherence tomography). Between them, these methods hold promise as outcome measures for early and later phase trials, but first require full validation.

Clinicians' perspectives concerning treatment initiation and escalation strategies for digital ulcers in patients with systemic sclerosis

Objectives

Digital ulcers (DUs) are a major cause of pain and disability in systemic sclerosis (SSc) patients and remain a major treatment challenge. Our aim was to explore clinicians' perspectives towards treatment initiation and escalation, akin to a 'Treat to Target' (T2T) strategy.

Methods

SSc clinicians were invited to participate in an online survey.

Results

A total of 173 responses (75% rheumatologists) were obtained from 33 countries. When initiating a change in oral drug therapy for SSc-DUs, most (80%) respondents would consider adding new medication to existing treatment, and 50% would increase existing treatment dose. Time to assess the impact of treatment change varied considerably, with around half (43.6%) waiting 1 month. Endothelin receptor antagonists, phosphodiesterase type-5 inhibitors and prostanoids were considered most efficacious for DU prevention, with good perceived efficacy from calcium channel blockers and moderate benefit from anti-platelet agents and immunosuppression. Side effects (e.g. headache and peripheral oedema) are perceived to be a significant issue with oral vasodilatory/vasoactive therapies in many patients. The highest rated T2T targets were (1) complete absence of new/recurrent DUs (63%), (2) reduction >50% in the number of DU recurrence (52%) and (3) reduction in DU healing time (37%) and reduction in DU pain >50% (37%). The most frequent reasons for hospitalisation were to administer intravenous treatment (91%) and DU complications (87%). Surgery is reserved for the threatened digit (e.g. gangrene), underlying calcinosis and failure of medical therapy.

Conclusion

Significant heterogeneity currently exists concerning treatment initiation and escalation for SSc-DUs, potentially amenable to a T2T strategy.

Vascular, Soft Tissue, and Musculoskeletal Imaging in Systemic Sclerosis

This review examines the role of various imaging techniques in assessing vascular and musculoskeletal manifestations in Systemic Sclerosis (SSc). Imaging modalities, such as thermography, capillaroscopy, ultrasound, optical coherence tomography, laser speckle contrast analysis, radiography, computed tomography, and MRI, offer valuable insights into SSc-related complications. Findings suggest that these techniques aid in diagnosing conditions like Raynaud phenomenon, digital ulcers, calcinosis, acro-osteolysis, and hand contractures. However, each modality has its advantages and limitations, necessitating a multimodal approach for comprehensive evaluation and accurate diagnosis of SSc-related manifestations.

Practical Use of Ultrasound in Modern Rheumatology-From A to Z

During the past 20 years, the use of ultrasound (US) in rheumatology has increased tremendously, and has become a valuable tool in rheumatologists' hands, not only for assessment of musculoskeletal structures like joints and peri-articular tissues, but also for evaluation of nerves, vessels, lungs, and skin, as well as for increasing the accuracy in a number of US-guided aspirations and injections. The US is currently used as the imaging method of choice for establishing an early diagnosis, assessing disease activity, monitoring treatment efficacy, and assessing the remission state of inflammatory joint diseases. It is also used as a complementary tool for the assessment of patients with degenerative joint diseases like osteoarthritis, and in the detection of crystal deposits for establishing the diagnosis of metabolic arthropathies (gout, calcium pyrophosphate deposition disease). The US has an added value in the diagnostic process of polymyalgia rheumatica and giant-cell arteritis, and is currently included in the classification criteria. A novel use of US in the assessment of the skin and lung involvement in connective tissue diseases has the potential to replace more expensive and risky imaging modalities. This narrative review will take a close look at the most recent evidence-based data regarding the use of US in the big spectrum of rheumatic diseases.

Diagnosis and management of systemic sclerosis-related calcinosis

INTRODUCTION

Calcinosis is common in patients with systemic sclerosis (SSc) and refers to the sub-epidermal deposition of calcium salts in the skin. SSc-related calcinosis is associated with significant morbidity, including through cutaneous ulceration and predisposition to become infected.

AREAS COVERED

After briefly addressing aetiopathogenesis, we describe the clinical burden of SSc-associated calcinosis and provide a structured and practical clinical approach to diagnosis and assessment, including discussion of the role of different imaging modalities. The multi-faceted treatment of SSc-associated calcinosis is presented under three broad headings of 'general measures,' and 'medical treatment' and 'surgical treatment.' We adopted a narrative approach to identify relevant manuscripts to inform our review.

EXPERT OPINION

SSc-related calcinosis is an area of major unmet clinical need and for too long has been a neglected area of research. Safe and effective treatments are badly needed to improve patient quality of life and outcomes. To facilitate future clinical trials, we require increased understanding of pathogenesis (to inform selection of potential targeted therapies) and reliable outcome measures, including those which will measure the impact and severity of calcinosis from the patient perspective. International collaborative research is ongoing to develop outcome measures and treatments for this potentially devastating complication of SSc.

Laser Speckle Contrast Analysis: Functional Evaluation of Microvascular Damage in Connective Tissue Diseases. Is There Evidence of Correlations With Organ Involvement, Such as Pulmonary Damage?

Laser speckle contrast analysis (LASCA) is a non-contact technique able to quantify peripheral blood perfusion (PBP) over large skin areas. LASCA has been used to study hand PBP in several clinical conditions. These include systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) and LASCA showed that PBP was significantly lower in these conditions than in healthy subjects (HS). Moreover, it has been demonstrated that LASCA is a safe technique also able to monitor digital ulcer perfusion and their evolution in SSc patients, during systemic and local treatment. The use of LASCA, coupled with reactivity tests is commonplace in the field of microvascular function research. Post-occlusive hyperemia reactivity (POHR) and local thermal hyperemia, associated with laser techniques are reliable tests in the evaluation of perfusion in SSc patients. Other studies used laser speckled techniques, together with acetylcholine and sodium nitroprusside iontophoresis, as specific tests of endothelium function. In conclusion, LASCA is a safe, non-contact reliable instrument for the quantification of PBP at skin level and can also be associated with reactivity tests to monitor disease progression and response to treatment in different connective tissue diseases.