Ultrasound is a recently introduced technique in the specialty of rheumatology. Although there is a historic precedent, ultrasonography came into our environment at the beginning of the nineties. Today, rheumatologists are showing increasing interest in this technique. The number of ultrasonography articles in journals of rheumatology is growing as are the national associations of Rheumatology who provide ultrasound training programs every year. At the beginning of training, rheumatologists are taught the correct standardization for exploring different anatomical areas, as well as the recognition of different tissues, both the normal and the pathological. However, physicians often need to know not only what happens in a local area, but also what happens to the patient in general. In other words, they need to find answers to questions like what disease does the patient have? or what is the degree of disease activity? Recent publications support the idea that ultrasound has the potential to improve the diagnostic and clinical assessment of patients. If so, ultrasound will change usual clinical practice and, in the near future, the way patients with rheumatic diseases are diagnosed and treated, with greater precision and effectiveness, itself an opportunity to improve health care standards. The question is whether this is a mere illusion of a small group of experts or if it is truly generalized and rising among rheumatologists. The answer to this question is relevant, as it could change our health care model and training programs.

During the past 15 years, the Spanish Society of Rheumatology has developed a systematic ultrasound training program and this has been extended and implemented across the country. In fact, more than 800 rheumatologists have been trained through an educational program consisting of 4 levels.1 Thanks to a recent national survey, we know that 90% of the departments of rheumatology of Spain have ultrasound and that 38.7% of rheumatologists use this technique.2 In this sense, our country could be a good model to understand the perception of ultrasound in clinical practice and how it is used in the decision making process. The main objective of this study was to know the opinion of rheumatologists on the usefulness of ultrasound in clinical practice and in the process of making diagnostic and therapeutic decisions.

It created a scientific committee composed of the 4 first authors of the study, which developed the survey questions and set the universe, after determining that Spain has 277 hospitals with more than 200 beds. The invitation to participate was made by email and addressed to the rheumatology units of 234 different centers, though they were not able to locate all of rheumatology departments or their email addresses. The working group on ultrasound of the Spanish Society of Rheumatology (ECOSER) emailed a personalized letter inviting the head of each unit or the person designated as the most suitable, to participate in the survey. After accepting the invitation, an online survey was accessed by an individual user name and password. The questionnaire consisted of 3 parts: (a) general data, (b) purpose and areas of common ultrasound examination, and (c) assessment of the utility of ultrasound in clinical practice in general and rheumatological diseases in particular. Only one answer was allowed per site, within a period between September 15 and October 20, 2011. The data collected were treated in accordance with Organic Law 15/1999, of December 13, Protection of Personal Data.

Descriptive analysis was performed for each variable, with analysis of means, medians and standard deviations where necessary.

When ultrasound was first used in rheumatology departments, early indications were similar to those in medical imaging departments and we carried out localized examination of shoulders, knees, hands or soft tissue. In fact, most often, only one anatomical region was explored. However, the current standard ultrasound exam may be changing in rheumatology and rheumatologists are going to consider not only what happens to the patient in a particular area, but also on a general level. This could be because, in recent years, numerous articles have been published on the validity of the ultrasound examination in different diseases and conditions.

However, the question is whether such studies are only representative of a small group of researchers not linked to clinical practice, or if they really help rheumatologists to address unmet needs in their practice and if this is changing the clinical routine. Providing an answer to this question was the main objective of our study and we think that in our context, it would be possible to do so.

The survey shows that nearly 50% of the ultrasound examination was performed to diagnose or know the disease activity of our patients. This pattern of use of ultrasound is in accordance with preliminary descriptive data, which suggest that rheumatologists have used this technique to examine more areas per patient and more ultrasounds were performed over small joints, as well as using this technique primarily to contribute to the diagnosis of active inflammation in addition to guiding injections, while less frequently using it to aid in diagnosis of a structural condition and soft tissue.3 Our study, conducted five years later, shows the progress of ultrasound and the use of this technique by rheumatologists not only to improve the diagnosis of our patients, but also to improve treatment decisions, including almost all rheumatic diseases, for example, inflammatory autoimmune diseases, storage articular diseases, vasculitis, spondylitis, systemic sclerosis, disorders of the salivary gland, etc. To our knowledge, this aspect has not been discussed before. Recently, the American College of Rheumatology (ACR) published a report on the reasonable use of musculoskeletal ultrasound in rheumatology clinical practice, using a literature review and a panel of experts.4 Our approach is different in that we turn to the general opinion of rheumatologists in clinical practice as both perspectives can be interesting and complementary.

Another interesting aspect of this research is that the perceived usefulness level differs between the different diseases and, except for some limitations discussed below, are consistent with the evidence.

As a limiting factor of the study, we should mention that this is an opinion poll, which implies a low level of evidence, although it is a good approach to understand what is happening. The analysis of the results might show some bias. In some cases, the results are more optimistic than the published evidence but, in others, the evidence is superior to the perceived utility expressed by the participants in the survey. Finally, another potential bias lies in the influence on the results of the different degree of diffusion of knowledge, courses and conferences on ultrasound on the different diseases.

Perceived usefulness is high for synovitis, which is consistent with evidence from numerous studies published on its validity.5 Ultrasound examination is accepted even in the most recent ACR/EULAR criteria for the classification of rheumatoid arthritis as a valid method for the detection of active synovitis.6 There are also studies showing that ultrasound can detect activity in patients in clinical remission7–9 and this is reflected in the responses.

For the study of entheses there is interesting evidence,10 even in the field of diagnosis11–13 and monitoring response to treatment, and it seems that rheumatologists are aware of such facts,14 although there is still a lot to prove in this field and evidence may be somewhat smaller to the opinions.

Ultrasound examination in joint storage diseases, in giant cell arteritis and polymyalgia rheumatica, has also obtained a positive Likert-scale score between 3 and 4 – and is seen as a useful tool for clinical practice. Perhaps the perception in giant cell arteritis and joint storage diseases is less than the published evidence. In the field of giant cell arteritis, there are 4 metaanalysis,15–17 the highest level of evidence. The limitation may be due to the difficulty to provide training in this technique because of the low prevalence of the disease. In the field of articular storage diseases, the perceived utility is probably less than18,19 the evidence, even in the case of calcium pyrophosphate crystal deposition disease. The proposed new EULAR classification criteria for Calcium dihydrate pyrophosphate deposit disease includes ultrasound as a valid criterion with more evidence than conventional radiology.20 The low level of perceived usefulness in outcomes for vascular atherosclerosis in inflammatory diseases, hypouricemic treatment interruption, the diagnosis of the sacroiliac joint, skin assessment in systemic sclerosis and examination of the salivary glands is due, probably, to the need to incorporate more validity studies to clinical practice in these areas.

When we analyze the time spent to provide training in ultrasound and extend this technique in our country in recent years, we see a potential relationship between support for such training, national conferences and special events with the general perception. In advanced courses, there is a special training on quantification and detection of both synovitis and the enthesis, and in our national congress, we pay special attention to synovitis in rheumatoid arthritis and different sonographic findings in cases of spondylitis and psoriatic arthritis. The perception of lower utility in other conditions with strong evidence, such as joint storage diseases and giant cell arteritis may be due to inadequate dissemination of scientific evidence in these fields. Perhaps, in the future, centers should move parallel to validated data in the literature and special training in advanced courses on ultrasound findings concerning rheumatic diseases at the patient level.

In summary, ultrasound is becoming a useful tool integrated in clinical practice and linked to the decision making processes of diagnosis, activity and treatment. We have detected some discrepancies between evidence and use and it is necessary to maintain a continuous training plan. However, there is no doubt that ultrasound is changing rheumatology.

The authors declare no conflict of interest.