Doctors learn the benefits of ultrasound

Sandra Ryan reports from the Musculoskeletal Imaging Masterclass for Clinicians, where attendees heard about the latest diagnostic developments

Within the last decade, ultrasound (US) and magnetic resonance imaging (MRI) have become established imaging techniques for the diagnosis and follow-up of patients with musculoskeletal disease.
The advancements in US imaging have been made possible through technological improvements, resulting in faster computers and higher-frequency transducers, making the systems more accessible in clinical practice. As US and MRI technology continues to develop and becomes more widespread, hospital staff will need access to training and information about how to use the techniques in managing musculoskeletal disease.
This is why a Musculoskeletal Imaging Masterclass for Clinicians was held in the Royal College of Physicians in Ireland (RCPI) last December, supported by Abbott. The meeting was held to give specialists interested in musculoskeletal disease the opportunity to learn from leading experts in the field of ultrasound and MRI imaging of the joints.
The Masterclass was comprised of state-of-the-art lectures on musculoskeletal ultrasound, image guided intervention and MRI imaging, as well as interactive group sessions and hands-on ultrasound scanning of real patients using the latest technology. Attendees had the unique opportunity to use the technology and see first-hand how it can help their patients.
Dr David Kane, Consultant Rheumatologist at the Adelaide and Meath Hospital, Dublin, and Chairperson of the Masterclass, opened the meeting by welcoming the attendees, which included rheumatologists, sports medicine physicians, pain specialists and radiologists.
“Musculoskeletal imaging is becoming extremely complex, with a massive range of modalities available to clinicians,” said Dr Kane. “This leads to the important question: when should we use each modality?”
Dr Kane said that by introducing imaging into patients’ treatment, clinicians can improve outcome, and that this is becoming a growing trend in Europe and, indeed, Ireland, since having imaging available in an outpatient setting aids immediate diagnosis.
“Imaging is especially helpful, as we know, in rheumatoid arthritis, for the detection of joint inflammation and erosion,” added Dr Kane. “By using imaging techniques to find changes early, we can greatly affect patient outcome.”
Available in outpatients
Dr Kane has led the use of the technology in Ireland with a programme in the Adelaide and Meath Hospital, where ultrasound imaging is available in the outpatient department, and he hopes it will become more widely used in Ireland in the coming years. Last year he, along with the Irish Society of Rheumatology (ISR), held a workshop for doctors to train them in the specialty, and they hope to continue the programme.
“More and more rheumatologists are using ultrasound to aid diagnosis for their patients. Surveys show only one-third actually do it themselves, with the rest ordering US and MRI from radiology departments,” said Dr Kane. “We wanted to hold this Masterclass to bring people together and talk about where and how imaging will fit into our practices, in all relevant specialties, and to educate ourselves in musculoskeletal ultrasound.”
Ultrasound imaging of inflammation
The first lecturer of the day was the Italian specialist Dr Emilio Filipucci, Consultant Rheumatologist at the Uni-versity of Ancona, Italy, whose talk focused on the use and benefits of Power Doppler ultrasound in patients with inflammation. He explained that Power Doppler ultrasonography (PDUS) was “at the forefront” of imaging technique.
“The profile of ultrasonography and magnetic resonance imaging has rapidly increased in the last decade,” said Dr Filipucci.
“And European clinicians have been at the forefront of guiding appropriate utilisation of radiographic and novel imaging techniques.”
He explained that the newer ultrasound techniques of colour and Power Doppler imaging provide colour maps of tissues — the amount of colour is related to the degree of blood flow, which may be of use in the assessment of vascular tissues that can occur in soft-tissue inflammation.
“The main rationale for colour/Power Doppler is the detection of increased soft tissue perfusion,” he said.
Dr Filipucci quoted research examining the benefits of Doppler scanning.
One study, published in Arthritis and Rheumatism in 2001, which examined the effectiveness of Power Doppler ultrasonography for assessing inflammatory activity in the metacarpophalangeal (MCP) joints of patients with rheumatoid arthritis (RA), found that PDUS was reliable for assessing inflammatory activity in the MCP joints of RA patients, using dynamic MRI as the standard.
Doppler ultrasound
Dr Filipucci quoted another study, published in the British Medical Journal in 2004, which evaluated the presence of flow by Doppler ultrasound in the wrist and finger joints (carpometacarpal 1, metacarpophalangeal, and proximal interphalangeal joints) of 27 healthy controls.
The study found that synovial vascularisation may be detected in healthy subjects using DUS; and that newer US machines have higher Doppler sensitivity, and it is necessary to be able to distinguish normal from pathological synovial flow.
Dr Filipucci outlined the main differences between PDUS flow-imaging modes (spectral Doppler and colour flow):
Spectral Doppler:
l Examines flow at one site;
l Detailed analysis of distribution of flow;
l Good temporal resolution – can examine flow waveform;
l Allows calculations of velocity and indices.
Colour flow:
l Overall view of flow in a region;
l Limited flow information;
l Poor temporal resolution/flow dynamics (frame rate can be low when scanning deep).
Ultrasound imaging in the spine and peripheral nerves
Next to speak was Prof Dominic Harmon, Consultant in Anaesthesia and Pain Medicine in the Midwestern Regional Hospital, Limerick, who focused on ultrasound techniques in pain medicine.
“Possible uses of ultrasound in pain medicine include diagnostic and therapeutic procedures on nerves; diagnostic and therapeutic procedures on soft tissues; and intra-articular injections,” said Prof Harmon.
He stated that ideal imaging should:
l Produce high-resolution images of both deep and superficial structures;
l Be safe, for both the operator and the patient;
l Offer ‘real-time’ guidance as well as portability;
l Should not require extra staff to operate and be compatible with existing pain block equipment;
l Should provide good outcomes, in terms of both diagnosis and treatment.
“You should aim to find the source of pain using this technology by injecting a small volume of local anaesthetic at the presumed anatomical source of pain,” said Prof Harmon. “We are looking for an improvement in pain and function.”
He then outlined the goals of a successful nerve block:
l It should be a fast procedure with fast block onset
l There should be no toxic side effects; use a low volume of local anaesthetic
l Only block the targeted neuronal structures, and ensure safe needle positioning, without complications
l There should be no procedure related pain for the patient.
Using ultrasound guidance for peripheral nerve blockade improves the specificity of diagnosis in chronic pain conditions, said the professor.
He outlined therapeutic procedures commonly used in pain therapy, which include steroids, lidocaine, neuromodulation and pulsed radiofrequency of peripheral nerves.
Finally, Prof Harmon outlined the main advantages of ultrasound in pain medicine:
l No radiation — meaning repeat ultrasounds are possible and it is safe in pregnancy;
l The technology is becoming more readily available and is portable and less expensive;
l Ultrasound allows you to see nerves, pathology, and the spread of local anaesthetic;
l You can follow treatment easily and the results are in real time.
“More randomised controlled trials as well as improved outcomes in pain therapy will tell us if ultrasound is a better diagnostic in this field, as well as safer,” said Prof Harmon.
The benefits of MRI imaging of the musculoskeletal system
The final speaker was Dr Arthur Grey, Consultant Radiologist at Belfast City Hospital, who provided a concise introduction to magnetic resonance imaging of the musculoskeletal system for clinicians.
In clinical practice, various modalities are used for whole-body imaging of the musculoskeletal system, including radiography, bone scintigraphy, computed tomography, MRI, and positron emission tomography-computed tomography (PET-CT).
Each has their own advantage, depending on the patients, said Dr Grey.
The unique soft-tissue contrast of MRI enables for precise assessment of bone marrow infiltration and adjacent soft tissue structures, so that alterations within the bone marrow may be detected before osseous destruction becomes apparent in CT, or metabolic changes occur on bone scintigraphy or PET scan.
Dr Grey added that other strengths of MRI include that it can “see through bone” and provides great contrast resolution.
Some weaknesses are that there can be poor spatial resolution, and CT and high frequency ultrasound can sometimes be best for the patient.
“Together with CT or PET-CT and its valuable additional metabolic information, MRI has great potential in the more comprehensive, more accurate, and earlier diagnosis of musculoskeletal diseases,” said Dr Grey.
Conclusion
The meeting concluded that there was a continuously increasing use in Ireland of both US and MRI to more accurately assess musculoskeletal disease. For rheumatologists the principal application of ultrasound is in diagnosing and monitoring inflammatory arthritis such as rheumatoid arthritis.
Pain specialists have developed ultrasound for guidance of nerve blocks and other interventional procedures.
The relative benefits of MRI and US need to be carefully considered when selecting imaging for patients but both are now widely available for improving patient care.