Power and spectral Doppler ultrasound in suspected active sacroiliitis: a comparison with magnetic resonance imaging as gold standard

Abstract

Objectives The objectives of this study were to study with Power Doppler US (PDUS) the SI joints (SIJs) of patients with suspected active sacroiliitis, to describe SIJ flows with spectral wave analysis (SWA) on Doppler US, and to correlate US data with both clinical characteristics and presence of SIJ bone marrow oedema (BME) in subsequent MRI. Methods A total of 42 patients (32 females and 10 males, mean age 46.8 years) with recent onset of inflammatory back pain (IBP) were included. Every patient underwent US examination with a convex 1–8 MHz probe [scoring PDUS signals with a three-point scale and describing flows in SWA calculating the mean Resistive Index (RI)] and subsequent MRI of the SIJs. Results PDUS signals were detected in 34 patients and 62 SIJs. In 29 patients and 56 SIJs, MRI revealed BME. A definite diagnosis of SpA was made in 32 patients. PDUS signals were more frequent (P < 0.0001) in patients with a final diagnosis of SpA, yielding a higher PDUS score (P = 0.0304). PDUS grading correlated with both BME grading (r = 0.740, P = 0.0001) and AS DAS (ASDAS) (r = 0.6257, P = 0.0004), but not with inflammatory reactants nor anthropometric data. Mean RI were, respectively, 0.60 and 0.73 (P < 0.0001) in patients with or without diagnosis of active sacroiliitis. The most inclusive RI cut-off resulted <0.70 [positive predictive value (PPV) 94%, accuracy 90%, P = 0.0001]. The best Likelihood Ratio (5.471) for RI to detect pathologic cases was obtained with a cut-off of <0.60 (PPV 96%). Conclusions PDUS and SWA of SIJs demonstrate good diagnostic accuracy for active sacroiliitis compared with MRI.

Doppler and Spectral Ultrasound of Sacroiliac Joints in Pediatric Patients with Suspected Juvenile Spondyloarthritis

“…A few previous publications have suggested a possible role of Doppler US in determining active sacroiliitis in adults [8][9][10][11][12][13][14][15][16][17][18][19], demonstrating a high specificity of this examination, in comparison with MRI as gold standard, and proposing it as a screening method for patients with inflammatory back pain.…”

“…The US examination of SIJs was performed as described in previous papers [8][9][10][11][12][13][14][15][16][17] (Figure 1A). The probe was positioned in transverse scan over the median line of the sacrum, at the spinous apophysis of first sacral vertebra.…”

“…Diagnosis of positive PDUS/SWA examination for active sacroiliitis was defined as: PDUS score > 0 and RI < 0.60, or PDUS score = 2 and RI < 0.70 [17].…”

“…In a few studies, ultrasound (US) and Doppler US with spectral wave analysis (SWA) were used as first assessment tool to detect active sacroiliitis in adult patients [7][8][9][10][11][12][13][14][15]. More recently, Ghosh et al and Falsetti et al suggested that Power Doppler US (PDUS) with SWA may be a non-inferior diagnostic modality compared with MRI in documenting active sacroiliitis in early SpA [16,17]. On the other hand, Doppler US has not been yet applied to the study of SIJs in children [18,19], and The European Society of Musculoskeletal Radiology (ESSR) arthritis subcommittee and the European Society of Paediatric Radiology (ESPR) musculoskeletal imaging taskforce attributed limited value to the usefulness of US in axial joints [20].…”

Inflammatory Bowel Diseases and Coexisting Spondyloarthritis: A Neglected and too Often Under-Reported Association by Radiologists. A Multicenter Study by Italian Research Group of Imaging in Rheumatology

“…Sacroiliitis (SI) represents the hallmark of SpA and it may be clinically silent or equivocal in physical examination tests at an early stage, giving magnetic resonance imaging (MRI) a pivotal role for diagnosis, especially in non-radiographic axial spondyloarthritis [8][9][10][11][12]. In fact, signs of sacroiliac joint (SIJ) inflammation, such as periarticular SIJ bone marrow edema (BME), soft tissue edema and osteitis, which constitute early findings of SI, can be detected only by MRI, which today represents a reference technique in rheumatology [12][13][14][15][16][17][18]. SIJ erosions, which appear later in the disease history, and other structural changes, including fat deposition, subchondral sclerosis, bony bridges and ankylosis, which represent an advanced disease stage, can be diagnosed by both conventional radiographs and computed tomography (CT), the latter having a higher sensitivity and specificity, although CT scan use is limited in young patients for radioprotection reasons [19].…”