Ultrasound in the diagnosis of calcium pyrophosphate dihydrate deposition disease. A systematic literature review and a meta-analysis.

OBJECTIVE: Ultrasonography (US) demonstrated to be a promising tool for the diagnosis of calcium pyrophosphate dihydrate deposition disease (CPPD). The aim of this systematic literature review (SLR) was to collect the definitions for the US elementary lesions and to summarize the available data about US diagnostic accuracy in CPPD. METHODS: We systematically reviewed all the studies that considered US as the index test for CPPD diagnosis without restrictions about the reference test or that provided definitions about US identification of CPPD. Sensitivity and specificity were calculated for each study and definitions were extrapolated. Subgroup analyses were planned by anatomical site included in the index text and different reference standards. RESULTS: Thirty-seven studies were included in this review. All the studies were eligible for the collection of US findings and all definitions were summarized. US description of elementary lesions appeared heterogeneous among the studies. Regarding US accuracy, 13 articles entered in the meta-analysis. Considering each joint structure, the sensitivity ranged between 0.77 (0.63-0.87) and 0.34 (0.16-0.58) while the specificity varies between 1.00 (0.89-1.00) and 0.92 (0.16-1.00). Considering the reference standards used, the sensibility ranged between 0.34 (0.02-0.65) and 0.87 (0.76-0.99) while specificity ranged between 0.84 (0.52-1.00) and 1.00 (0.99-1.00). CONCLUSION: US is potentially a useful tool for the diagnosis of CPPD but universally accepted definitions and further testing are necessary in order to assess the role of the technique in the diagnostic process.

Change perspective to increase diagnostic accuracy of ultrasonography in calcium pyrophosphate dehydrate deposition disease! A new approach: the axial scan of the meniscus.

Ultrasonography (US) is a relevant tool in the study of calcium pyrophosphate dihydrate (CPP) deposition disease. However, differential diagnosis of hyperechoic deposits within the fibrocartilage can be difficult; moreover, US study is limited by the need of an adequate acoustic window. We describe a US scanning technique that offers a new viewpoint in the study of knee meniscal structure: a longitudinal scan performed according to the long axis of meniscus. This technique proves to be particularly useful for the identification of CPP deposition, but could also improve the US diagnostic utility and accuracy in other meniscal pathologies.

Prevalence of Baker's cyst in patients with knee pain: an ultrasonographic study.

The objectives of this study are to investigate the prevalence of Baker's cyst (BC) in patients with knee pain, and to assess the correlation between BC and severity of osteophytes and joint effusion. A retrospective study was conducted on a group of patients with knee pain referred to our outpatient clinic for ultrasonography of the knee between January 2010 and February 2011. Patients underwent an ultrasonographic exam of the knees to assess the presence of marginal femorotibial osteophytosis, joint effusion and BC. A dichotomous score was assigned to each item (1 present, 0 absent) and severity of US signs of osteoarthritis and joint effusion were also graded semiquantitatively. Collected data were processed using logistic regression analysis to evaluate the correlation between degree of osteophytosis and joint effusion and BC. Patients affected by inflammatory joint conditions or with history of joint surgery or recent trauma were excluded. A total of 399 patients with knee pain were studied (299 women), in the age range 18-89 years (mean 56.2, SD 16.3 years). 293 patients (73.4%) showed sonographic features of osteoarthritis and 251 (62.9%) joint effusion. BC was found in 102 patients (25.8%) together with a positive association with sonographic features of osteoarthritis and joint effusion. Our data show a prevalence of BC of 25.8% in a population of patients with knee pain, and suggest that BC is positively related to osteoarthritis and joint effusion. Ultrasonographic examination of knee is worthwhile in patients with painful osteoarthritis or evidence of effusion.

Radiologists and rheumatologists on performing and reporting shoulder ultrasound: from disagreement to consensus.

Shoulder pain is a common condition in the rheumatologist's practice, yet there are no guidelines on how to report shoulder ultrasound (US) examinations. The aim of this study was to compare scanning and reporting techniques performed by radiologists and rheumatologists and identify any discrepancies between the two. The participants in this study were five rheumatologists and two radiologists specialized in musculoskeletal US. The study was divided in 2 phases. In the first phase, each participant performed an US of 3 patients and reported the findings without knowing the patient diagnosis and the findings reported by the other operators. Other three investigators reported the US technique of each operator. Reports and images were subsequently compared to identify any discrepancies and reach consensus on a common approach. In the second phase, a US scan was performed on a fourth patient in a plenary session to assess feasibility and efficacy of the common approach The US scanning technique was similar for all operators. The differences in reporting emerged in the description of the rotator cuff disease. Radiologists provided a detailed description of lesions (measurements along 2 axis and scoring of lesions), whereas rheumatologists described carefully the inflammatory changes. The experts concluded that lesions should be measured along 2 axes and the grade of degeneration and the age of the lesion should be reported. Another difference emerged in the description of the irregularities of the bone surface. The experts concluded that the term erosion should be used only when an inflammatory joint disease is suspected. This study led to the clarification of some inconsistencies in US reporting, and represented an interesting collaborative experience between radiologists and rheumatologists.