Imaging as a follow-up tool in clinical trials and clinical practice

Value of multi-slice spiral computed tomography in the diagnosis of metastatic lymph nodes and N-stage of gastric cancer

Objective

To establish new diagnostic criteria for improvement of the accuracy of multi-slice spiral computed tomography (MSCT) in diagnosing the N-stage and lymph node (LN) metastasis of gastric cancer (GC).

Methods

MSCT was performed with plain and triphasic dynamic contrast enhancement. Different regions of LN metastasis and N-staging were determined according to the herein-proposed combined diagnostic criteria and were then correlated with the pathological analysis. The Kappa consistency test was used to study the accuracy of MSCT.

Results

The accuracy of MSCT in diagnosing the N-stage as a whole was 86.3%, and that in diagnosing LN metastasis was 79.1% to 98.9%. The Kappa values for stages N0, N1, and N3 ranged from 0.449 to 0.662, indicating good consistency in diagnosing these three stages between MSCT and the postsurgical pathological results. The K_total value was 0.567 between MSCT and the postsurgical pathological results in diagnosing LN metastasis. The risk of LN metastasis increased with the progression of lesion infiltrates.

Conclusions

Application of the combined diagnostic criteria increased the diagnostic performance of MSCT in not only judging the N-stage but also diagnosing LN metastasis. This study will provide valuable reference data for surgical planning for patients with GC in the clinical setting.

MR Imaging of Joint Infection and Inflammation with Emphasis on Dynamic Contrast-Enhanced MR Imaging

Contrast-enhanced MR imaging (CE-MR imaging) is recommended for diagnosis and monitoring of infectious and most inflammatory joint diseases. CE-MR imaging clearly differentiates soft and bony tissue from fluid collections and infectious debris. To improve imaging information, a dynamic CE-MR imaging sequence (DCE-MR imaging) sequence can be applied using fast T1-weighted sequential image acquisition during contrast injection. Use of DCE-MR imaging allows robust extraction of quantitative information regarding blood flow and capillary permeability, especially when dedicated analysis methods and software are used to analyze contrast kinetics. This article describes principles of DCE-MR imaging for the assessment of infectious and inflammatory joint diseases.

Ultrasound in Arthritis

Ultrasound is currently performed in everyday rheumatologic practice. It is used for early diagnosis, to monitor treatment results, and to diagnose remission. The spectrum of pathologies seen in arthritis with ultrasound includes early inflammatory features and associated complications. This article discusses the spectrum of ultrasound features of arthritides seen in rheumatoid arthritis and other connective tissue diseases in adults, such as Sjögren syndrome, lupus erythematosus, dermatomyositis, polymyositis, and juvenile idiopathic arthritis. Ultrasound findings in spondyloarthritis, osteoarthritis, and crystal-induced diseases are presented. Ultrasound-guided interventions in patients with arthritis are listed, and the advantages and disadvantages of ultrasound are discussed.

Does rheumatoid synovitis activity vary during the day? Evaluation with color doppler sonography

Background

Clinical symptoms of rheumatoid arthritis (RA) improve in the course of the day, as can synovitis activity, reported via doppler ultrasound (US). The aim of the study was to establish whether the Color Doppler (CD) scores of synovitis in RA changes throughout the day.

Methods

In total, 27 patients with active RA, including 14 patients receiving corticosteroids were studied. US evaluation was performed twice in each patient, at 9 a.m. (T0) and after 4 p.m. (T1) on the same day by a single radiologist and using the same instrument. Overall, 30 joints were assessed, including grey scale and CD (S0 = no flow [no detectable CD)]; S1 = mild [CD <1/3 of the synovium]; S2 = moderate [CD <2/3]; S3 = pronounced [CD >2/3]).

Results

In the total population, synovitis was detected more often in the evening than in the morning (39% vs. 33%, p = 0.02). The difference remained significant only in patients without corticosteroid administration (44% vs. 37%, p = 0.04). Moreover, a greater number of CD-positive joints were likewise found (S0 vs. S1 + S2 + S3) in the evening (57% vs. 51%, p = 0.04) in patients not receiving corticosteroids (67% vs. 41%, p = 0.002). More moderate (S2) and pronounced (S3) than mild (S1) synovitis was observed at T1 vs. T0 (39% vs. 24%, p = 0.03) in patients not receiving corticosteroids. More synovitis (40% vs 36% p = 0.02) in the dominant hand were found in the evening than in the morning.

Conclusion

Synovitis and CD activity increase during the day in RA patients, especially in joints of the dominant hands and in patients without corticosteroids.

The association between histological, macroscopic and magnetic resonance imaging assessed synovitis in end-stage knee osteoarthritis: a cross-sectional study

OBJECTIVES

To investigate the association between magnetic resonance imaging (MRI), macroscopic and histological assessments of synovitis in end-stage knee osteoarthritis (KOA).

METHODS

Synovitis of end-stage osteoarthritic knees was assessed using non-contrast-enhanced (CE), contrast-enhanced magnetic resonance imaging (CE-MRI) and dynamic contrast-enhanced (DCE)-MRI prior to (TKR) and correlated with microscopic and macroscopic assessments of synovitis obtained intraoperatively. Multiple bivariate correlations were used with a pre-specified threshold of 0.70 for significance. Also, multiple regression analyses with different subsets of MRI-variables as explanatory variables and the histology score as outcome variable were performed with the intention to find MRI-variables that best explain the variance in histological synovitis (i.e., highest R²). A stepped approach was taken starting with basic characteristics and non-CE MRI-variables (model 1), after which CE-MRI-variables were added (model 2) with the final model also including DCE-MRI-variables (model 3).

RESULTS

39 patients (56.4% women, mean age 68 years, Kellgren-Lawrence (KL) grade 4) had complete MRI and histological data. Only the DCE-MRI variable MExNvoxel (surrogate of the volume and degree of synovitis) and the macroscopic score showed correlations above the pre-specified threshold for acceptance with histological inflammation. The maximum R²-value obtained in Model 1 was R² = 0.39. In Model 2, where the CE-MRI-variables were added, the highest R² = 0.52. In Model 3, a four-variable model consisting of the gender, one CE-MRI and two DCE-MRI-variables yielded a R² = 0.71.

CONCLUSION

DCE-MRI is correlated with histological synovitis in end-stage KOA and the combination of CE and DCE-MRI may be a useful, non-invasive tool in characterising synovitis in KOA.

Matrix-Associated Autologous Chondrocyte Implantation: A Clinical Follow-Up at 15 Years

INTRODUCTION

A prospective clinical investigation was carried out in order to clarify whether Matrix-associated autologous chondrocyte implantation (MACI) results in clinical improvement at long-term follow-up.

HYPOTHESIS

MACI will result in clinical improvement at long-term follow-up.

STUDY DESIGN

Case series; level of evidence, 4.

METHODS

Thirty-eight patients were treated with MACI. These patients were evaluated for up to a mean of 16 years (range 15-17 years) after the intervention. Three different scores (Lysholm-Gilquist score, International Cartilage Repair Society score, and Tegner score) formed the basis of this study. Overall, we were able to obtain valid preoperative and postoperative results from 18 (47%) of 38 patients. In 1 patient, both knees were treated. In 4 patients, an arthroplasty was implanted over the course of time; thus they were excluded from this case series. In conclusion, follow-up of 15 knees was performed in the recent series.

RESULTS

In subjective rating, 12 out of 14 patients (86%) rated the function of their knee as much better or better than before the index procedure. All numerical outcome scores showed significant improvement compared to the preoperative value (preoperative/postoperative at 5 years/postoperative at 15 years): Lysholm score 59.6 (±24.6)/78.6 (±21.5)/82.7 (±11.3), International Knee Documentation Committee score 50.6 (±22.7)/64.7 (±21.6)/69.7 (±18.7), Tegner score 3.0 (±2.2)/3.6 (±1.5)/5.2 (±1.7).

CONCLUSION

The significantly improved results on 3 scores after 15 years suggest that MACI represents a suitable treatment of local cartilage defects in the knee.

Associations between muscle perfusion and symptoms in knee osteoarthritis: a cross sectional study

OBJECTIVE

To investigate the association between muscle perfusion in the peri-articular knee muscles assessed by dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) and symptoms in patients with knee osteoarthritis (KOA).

DESIGN

In a cross-sectional setting, muscle perfusion was quantified by DCE-MRI in KOA. Regions of interest (ROI) were drawn around the peri-articular muscles, summed and averaged into one single "Total Muscle Volume" volume of interest (VOI). Symptoms were assessed via the Knee injury and Osteoarthritis Outcome Score (KOOS) (0: worst; 100: best).

RESULTS

DCE-MRI and clinical data were analyzed in 94 patients. The typical participant was a woman with a mean age of 65 years, and a body mass index (BMI) of 32 kg/m(2). Reduced multiple regression models analyzing the association between KOOS and DCE-MRI perfusion variables of Total Muscle Volume showed a statistically significant association between Nvoxel% and KOOS pain (0.41 (SE 0.14); P = 0.0048). Nvoxel% was defined as the proportion of highly perfused voxels; i.e., the voxels that show an early and rapid increase on the signal intensity vs time curves, reach a plateau state (plateau pattern) and then showing a relatively rapid decline (washout pattern) relative to the total number of voxels within the muscle VOI.

CONCLUSIONS

More widespread perfusion in the peri-articular knee muscles was associated with less pain in patients with KOA. These results give rise to investigations of the effects of exercise on muscle perfusion and its possible mediating role in the causal pathway between exercise and pain improvements in the conservative management of KOA.

Knee pain and inflammation in the infrapatellar fat pad estimated by conventional and dynamic contrast-enhanced magnetic resonance imaging in obese patients with osteoarthritis: a cross-sectional study

OBJECTIVE

To investigate the association between knee pain and signs of inflammation in the infrapatellar fat pad (IPFP) in obese patients with knee osteoarthritis (KOA).

DESIGN

In a cross-sectional setting, 3-T conventional contrast-enhanced (CE) magnetic resonance imaging (MRI) and dynamic contrast-enhanced (DCE)-MRI of KOA were analysed to quantify the extent of inflammation in the IPFP, and correlated (Spearman's rank correlation) to pain and other symptoms assessed via the Knee injury and Osteoarthritis Outcome Score (KOOS) (100 = no pain, 0 = extreme pain). The extent of inflammation in the IPFP was assessed according to the MRI Osteoarthritis Knee Score (MOAKS) using CE-MRI and by DCE-MRI perfusion variables. The perfusion variable, "Inflammation", was chosen as primary perfusion variable in the analysis. Intraclass correlation coefficients for the perfusion variables ranged from 0.81 to 0.99.

RESULTS

MRI and clinical data were obtained in 95 patients. The typical patient was a woman (82%) with an average age of 65 years (SD 6.5) and a body mass index (BMI) of 32 kg/m(2) (SD 3.7). The bivariate association between KOOS pain and the DCE-MRI perfusion variable "Inflammation" showed a statistically significant correlation (r = -0.42, P < 0.0001). A statistically significant correlation was also found between KOOS pain and MOAKS Hoffa-synovitis (r = -0.21, P = 0.046).

CONCLUSIONS

Perfusion variables on DCE-MRI reflecting the severity of inflammation in the IPFP and MOAKS Hoffa-synovitis were associated with the severity of pain in KOA. These results suggest that severe inflammation in the IPFP is associated with severe pain in KOA and that DCE-MRI is a promising method to study the impact of inflammation in KOA.

Use of a novel high-resolution magnetic resonance neurography protocol to detect abnormal dorsal root Ganglia in Sjögren patients with neuropathic pain: case series of 10 patients and review of the literature

The diagnosis and treatment of patients with Sjögren syndrome (SS) with neuropathic pain pose several challenges. Patients with SS may experience unorthodox patterns of burning pain not conforming to a traditional "stocking-and-glove" distribution, which can affect the face, torso, and proximal extremities. This distribution of neuropathic pain may reflect mechanisms targeting the proximal-most element of the peripheral nervous system-the dorsal root ganglia (DRG). Skin biopsy can diagnose such a small-fiber neuropathy and is a surrogate marker of DRG neuronal cell loss. However, SS patients have been reported who have similar patterns of proximal neuropathic pain, despite having normal skin biopsy studies. In such cases, DRGs may be targeted by mechanisms not associated with neuronal cell loss. Therefore, alternative approaches are warranted to help characterize abnormal DRGs in SS patients with proximal neuropathic pain.We performed a systematic review of the literature to define the frequency and spectrum of SS peripheral neuropathies, and to better understand the attribution of SS neuropathic pain to peripheral neuropathies. We found that the frequency of SS neuropathic pain exceeded the prevalence of peripheral neuropathies, and that painful peripheral neuropathies occurred less frequently than neuropathies not always associated with pain. We developed a novel magnetic resonance neurography (MRN) protocol to evaluate DRG abnormalities. Ten SS patients with proximal neuropathic pain were evaluated by this MRN protocol, as well as by punch skin biopsies evaluating for intraepidermal nerve fiber density (IENFD) of unmyelinated nerves. Five patients had radiographic evidence of DRG abnormalities. Patients with MRN DRG abnormalities had increased IENFD of unmyelinated nerves compared to patients without MRN DRG abnormalities (30.2 [interquartile range, 4.4] fibers/mm vs. 11.0 [4.1] fibers/mm, respectively; p = 0.03). Two of these 5 SS patients whose neuropathic pain resolved with intravenous immunoglobulin (IVIg) therapy had improvement of MRN DRG abnormalities.We have developed a novel MRN protocol that can detect DRG abnormalities in SS patients with neuropathic pain who do not have markers of peripheral neuropathy. We found that SS patients with MRN DRG abnormalities had statistically significant, increased IENFD on skin biopsy studies, which may suggest a relationship between trophic mediators and neuropathic pain. Given that our literature review has demonstrated that many SS neuropathic pain patients do not have a neuropathy, our findings suggest an important niche for this MRN DRG technique in the evaluation of broader subsets of SS neuropathic pain patients who may not have underlying neuropathies. The improvement of MRN DRG abnormalities in patients with IVIg-induced remission of neuropathic pain suggests that our MRN protocol may be capturing reversible, immune-mediated mechanisms targeting the DRG.

Imaging of rheumatoid arthritis

Increased awareness of the need for early diagnosis of rheumatoid arthritis and advances in the ability to effectively treat rheumatoid arthritis have made disease remission and maintenance of function a reality for many patients. However, identification of patients who are at risk for erosive disease remains a challenge. As more is learnt about risk factors for disease severity and the role of imaging techniques such as ultrasound and magnetic resonance imaging, the ability to prevent disease progression in the form of joint damage and its attendant deformity and functional limitation will further improve.

Usefulness of sonography in the diagnosis of rheumatoid hand

Ultrasound examination is becoming more and more common in patients with rheumatoid diseases. Above all, it enables the assessment of articular soft tissues and constitutes a non-invasive examination. In a rheumatologist's everyday practice, it is conducted at the stage of initial diagnosis as well as to monitor the treatment and to confirm the remission if the clinical picture is ambiguous. The first sign of arthritis (including rheumatoid arthritis) that is visible on ultrasound examination is the thickening of the synovial membrane of the joint cavities, tendon sheaths or bursae. It is frequently accompanied by the exudate in the joint, sheath or bursa. In a subsequent stage, in Doppler examination, enhanced vascularization of the synovial membrane is observed. Sometimes, the inflammatory process of the tendon sheaths also affects the tendons, which might lead to their damage. Moreover, ultrasound examination also reveals erosions and inflammatory cysts (geodes) which attest to the advancement of the disease. A dynamic ultrasound examination enables to diagnose the capsule-ligamentous contracture of the interphalangeal joints, which occurs due to the lack of rehabilitation that should begin at the moment of the commencement of the inflammation. The ultrasound image does not allow for the differentiation between various rheumatoid entities, including those encompassing the joints in the hand, wrist. The observed changes, i.e. thickening of the synovial membrane, hyperemia, effusions, erosions or tendon damage, may accompany various rheumatoid entities. The purpose of the ultrasound examination is to recognize these irregularities, determine their localization and advancement and, finally, to monitor the course of treatment. Furthermore, ultrasound scan enables to assess the joints and tendons in a dynamic examination in relation to local ailments of the patient as well as to monitor the biopsy, aspiration and medicine administration. Sonography is used for a US-guided administration of radioisotope substances for synoviorthesis.

The pathogenesis of rheumatoid arthritis in radiological studies. Part II: Imaging studies in rheumatoid arthritis

Early diagnosis of rheumatoid arthritis followed by early initiation of treatment, prevent the destruction of joints and progression to disability in the majority of patients. A traditional X-ray fails to capture early inflammatory changes, while late changes (e.g. erosions) appear after a significant delay, once 20–30% of bone mass has been lost. Sonography and magnetic resonance imaging studies have shown that erosions are seen in the first 3 months from the appearance of symptoms in 10–26% of patients, while in 75% they are seen in the first 2 years of the disease. Power Doppler ultrasound and dynamic magnetic resonance studies allow for qualitative, semiquantitative and quantitative monitoring of the vascularization of the synovium. In addition, magnetic resonance enables assessment of the bone marrow. The ultrasonographic examination using a state-of-the-art apparatus with a high-frequency probe allows for images with great spatial resolution and for the visualization of soft tissues and bone surfaces. However, the changes seen in ultrasonography (synovial pathologies, the presence of exudate, tendons changes, cartilage and bone lesions, pathologies of tendon attachments and ligaments – enthesopathies) are not only specific for rheumatoid arthritis and occur in other rheumatic diseases. Qualitative methods are sufficient for diagnosing the disease through ultrasound or magnetic resonance imaging. Whereas semiquantitative and quantitative scales serve to monitor the disease course – efficacy of conservative treatment and qualification for radioisotope synovectomy or surgical synovectomy – and to assess treatment efficacy.

The interobserver reliability of ultrasound in knee osteoarthritis

OBJECTIVE

To assess the interobserver reliability between sonographers with different levels of experience in detecting inflammatory and structural damage abnormalities in patients with knee OA.

METHODS

After achieving consensus on definitions and scanning protocols, three ultrasonographers with different levels of experience in musculoskeletal US examined the knees of nine patients with OA. US examinations were conducted with independent blinded evaluations of inflammatory (joint effusion, synovial hypertrophy, power Doppler signal, Baker's cysts) and structural (osteophytes, cortical bone irregularities, femoral hyaline cartilage abnormalities, protrusion of the medial meniscus) lesions. All abnormalities were scored by applying a dichotomous scale (0-1). In addition, at each knee joint site global scores for joint inflammation, cortical bone abnormalities and cartilage damage were calculated by summing the single-lesion scores. Reliability was assessed using kappa (κ) coefficients.

RESULTS

Seventeen knees were examined. Inflammatory abnormalities were observed with moderate to very good agreement (κ = 0.55-0.88) between the observers. From fair to very good agreement (κ = 0.31-0.82) was registered between sonographers for structural damage lesions. The overall κ was 0.716 for junior and 0.571 for beginner sonographers comparing their findings with those of senior sonographers.

CONCLUSION

This represents the first ultrasonographic study focusing on the analysis of interobserver reliability between sonographers with different levels of experience in demonstrating inflammatory and structural abnormalities in knee OA. Globally, even considering some variable results that were mainly obtained by the evaluation of single components of bone involvement, US offered a reliable assessment of a wide set of abnormalities in knee OA.

Emerging role of ultrasonography in rheumatoid arthritis: optimizing diagnosis, measuring disease activity and identifying prognostic factors

Ultrasonography is a sensitive imaging modality that provides valuable information regarding early inflammatory changes that are not detected by clinical examination or X-rays, such as subclinical synovitis and erosions. This information may improve the management of rheumatoid arthritis by providing a more timely and accurate diagnosis, identifying poor prognostic factors, more accurately monitoring response to therapeutic intervention, improving treatment decisions and more accurately assessing remission. Ultrasonography could play a critical role in minimizing disease activity through strict monitoring and aggressive therapeutic adjustment, which has emerged as an approach to improve long-term outcomes for patients with rheumatoid arthritis.

Real-time co-registration using novel ultrasound technology: ex vivo validation and in vivo applications

OBJECTIVE

The study objective was to evaluate whether a novel global position system (GPS)-like position-sensing technology will enable accurate co-registration of images between imaging modalities. Co-registration of images obtained by different imaging modalities will allow for comparison and fusion between imaging modalities, and therefore has significant clinical and research implications. We compared ultrasound (US) and magnetic resonance imaging (MRI) scans of carotid endarterectomy (CEA) specimens using a novel position-sensing technology that uses an electromagnetic (EM) transmitter and sensors mounted on a US transducer. We then evaluated in vivo US-US and US-MRI co-registration.

METHODS

Thirteen CEA specimens underwent 3.0 Tesla MRI, after which images were uploaded to a LOGIQ E9 3D (GE Healthcare, Wauwatosa, WI) US system and registered by identifying two to three common points. A similar method was used to evaluate US-MRI co-registration in patients with carotid atherosclerosis. For carotid intima-media thickness (C-IMT) measurements, 10 volunteers underwent bilateral carotid US scans co-registered to three-dimensional US maps created on the initial visit, with a repeat scan 2 days later.

RESULTS

For the CEA specimens, there was a mean of 20 (standard error [SE] 2.0) frames per MRI slice. The mean frame difference, over 33 registration markers, between MRI and US scans for readers 1 and 2 was -2.82 ± 19.32 and 2.09 ± 14.68 (mean ± 95% CI) frames, respectively. The US-MRI intraclass correlation coefficients (ICCs) for the first and second readers were 0.995 and 0.997, respectively. For patients with carotid atherosclerosis, the mean US frames per MRI slice (9 [SE 2.3]) was within range of that observed with CEA specimens. Inter-visit, intra-reader, and inter-reader reproducibility of C-IMT measurements were consistently high (side-averaged ICC >0.9).

CONCLUSION

Accurate co-registration between US and other modalities is feasible with a GPS-like technology, which has significant clinical and research applicability.

Mid-term results of Autologous Matrix-Induced Chondrogenesis for treatment of focal cartilage defects in the knee

Articular cartilage defects heal poorly. Autologous Matrix-Induced Chondrogenesis (AMIC) is an innovative treatment for localized full-thickness cartilage defects combining the well-known microfracturing with collagen scaffold and fibrin glue. The purpose of this prospective study was to evaluate the medium-term results of this enhanced microfracture technique for the treatment of chondral lesions of the knee. Thirty-two chondral lesions in 27 patients were treated with AMIC. Within the context of clinical follow-up, these patients were evaluated for up to 5 years after the intervention. Five different scores (Meyer score, Tegner score, Lysholm score, ICRS score, Cincinnati score) as well as radiographs were used for outcome analysis. Articular resurfacing was assessed by magnetic resonance imaging (MRI). The average age of patients (11 females, 16 males; mean body mass index 26, range 20-32) was 37 years (range 16-50 years). The mean defect size of the chondral lesions was 4.2 cm(2) (range 1.3-8.8 cm(2)). All defects were classified as grade IV according to the Outerbridge classification. The follow-up period was between 24 and 62 months with a mean of 37 months. Twenty out of 23 individuals (87%) questioned were subjectively highly satisfied with the results after surgery. Significant improvement (P < 0.05) of all scores was observed as early as 12 months after AMIC, and further increased values were notable up to 24 months postoperatively. MRI analysis showed moderate to complete filling with a normal to incidentally hyperintense signal in most cases. Results did not show a clinical impact of patient's age at the time of operation, body mass index and number of previous operations (n.s.). In contrast, males showed significant higher values in the ICRS score compared to their female counterparts. AMIC is an effective and safe method of treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases. However, further studies with long-term follow-up are needed to determine whether the grafted area will maintain structural and functional integrity over time.