Five simultaneous artificial intelligence data challenges on ultrasound, CT, and MRI.

PURPOSE: The goal of this data challenge was to create a structured dynamic with the following objectives: (1) teach radiologists the new rules of General Data Protection Regulation (GDPR), while building a large multicentric prospective database of ultrasound, computed tomography (CT) and MRI patient images; (2) build a network including radiologists, researchers, start-ups, large companies, and students from engineering schools, and; (3) provide all French stakeholders working together during 5 data challenges with a secured framework, offering a realistic picture of the benefits and concerns in October 2018. MATERIALS AND METHODS: Relevant clinical questions were chosen by the Société Francaise de Radiologie. The challenge was designed to respect all French ethical and data protection constraints. Multidisciplinary teams with at least one radiologist, one engineering student, and a company and/or research lab were gathered using different networks, and clinical databases were created accordingly. RESULTS: Five challenges were launched: detection of meniscal tears on MRI, segmentation of renal cortex on CT, detection and characterization of liver lesions on ultrasound, detection of breast lesions on MRI, and characterization of thyroid cartilage lesions on CT. A total of 5,170 images within 4 months were provided for the challenge by 46 radiology services. Twenty-six multidisciplinary teams with 181 contestants worked for one month on the challenges. Three challenges, meniscal tears, renal cortex, and liver lesions, resulted in an accuracy>90%. The fourth challenge (breast) reached 82% and the lastone (thyroid) 70%. CONCLUSION: Theses five challenges were able to gather a large community of radiologists, engineers, researchers, and companies in a very short period of time. The accurate results of three of the five modalities suggest that artificial intelligence is a promising tool in these radiology modalities.

Comparison of bone lesion distribution between prostate cancer and multiple myeloma with whole-body MRI.

PURPOSE: To assess the distribution of bone lesions in patients with prostate cancer (PCa) and those with multiple myeloma (MM) using whole-body magnetic resonance imaging (MRI); and to assess the added value of four anatomical regions located outside the thoraco-lumbo-pelvic area to detect the presence of bone lesions in a patient-based perspective. MATERIALS AND METHODS: Fifty patients (50 men; mean age, 67±10 [SD] years; range, 59-87 years) with PCa and forty-seven patients (27 women, 20 men; mean age, 62.5±9 [SD] years; range, 47-90 years) with MM were included. Three radiologists assessed bone involvement in seven anatomical areas reading all MRI sequences. RESULTS: In patients with PCa, there was a cranio-caudal increasing prevalence of metastases (22% [11/50] in the humeri and cervical spine to 60% [30/50] in the pelvis). When the thoraco-lumbo-pelvic region was not involved, the prevalence of involvement of the cervical spine, proximal humeri, ribs, or proximal femurs was 0% in patients with PCa and≥4% (except for the cervical spine, 0%) in those with MM. CONCLUSION: In patients with PCa, there is a cranio-caudal positive increment in the prevalences of metastases and covering the thoraco-lumbo-pelvic area is sufficient to determine the metastatic status of a patient with PCa. In patients with MM, there is added value of screening all regions, except the cervical spine, to detect additional lesions.

Coracoid bone block transfer procedure: Correlation between subscapularis volume below the bone graft and shoulder stability.

INTRODUCTION: Coracoid bone graft transfer has become the gold standard in patients with recurrent anterior shoulder instability associated with bony defect. Several studies have shown that the main stabilizing component of this procedure is the sling effect by the conjoint tendon and the lower portion of subscapularis (SS). The purpose of this study was to determine whether a larger SS volume below the bone block was correlated to greater postoperative shoulder stability. MATERIALS AND METHODS: This prospective study included a cohort of patients who underwent open coracoid bone graft transfer for post-traumatic recurrent anterior shoulder instability. Forty patients were reviewed at 2 years with a clinical and CT scan evaluation. A correlation analysis assessed the relation between the SS volume index (ratio of SS volume below the bone block to volume over the bone block) and Rowe and Walch-Duplay instability scores. RESULTS: There exists a positive and significant correlation between SS volume index and postoperative Rowe score, r=0.37 (P=0.03). The same trend was observed for Walch-Duplay score without statistical significance. A larger inferior SS volume did not result in a limitation of external rotation, greater fatty infiltration, or malposition of the coracoid graft. CONCLUSION: A larger SS volume below the bone block is related to greater postoperative shoulder stability. We recommend performing the split in the middle of the SS or higher instead of the junction of the superior two-thirds and inferior one-third as usually reported. LEVEL OF EVIDENCE: III, prospective study.

Imaging of tumors and tumor-like lesions of the knee.

Tumors and tumor-like lesions of the knee are common conditions. Because the synovial membrane covers a large part of the knee, tumors and tumor-like lesions of the knee are mostly synovial. Magnetic resonance imaging (MRI) plays a major role in the assessment and characterization of these lesions. However, the diagnostic approach of these lesions must be performed systematically. First, the lesion must be precisely located, and then the anatomical structure involved must be determined. Finally, clinical background that includes the age of the patient, frequency of the disease and, if any, associated signs as well as MRI characteristics must be analyzed. In this review, we describe the anatomy of the knee and its compartments and provide a description of the main tumors and tumor-like lesions of the knee. We present a diagnostic approach based on the location within the knee of the lesions and the anatomical structures involved.

Rare carpometacarpal dislocations.

Posttraumatic carpal and carpometacarpal dislocations represent a heterogeneous group of disorders resulting from high-energy wrist trauma. Perilunate injury is the most common and best-known manifestation of carpal dislocation, typically occurring after hyperextension trauma. Other forms are very rare and have different causative mechanisms. Carpometacarpal (CMC) dislocations are also uncommon and may affect isolated or multiple CMC joints. These lesions are prone to wrist instability if not treated promptly. The aim of this article is to provide a systematic radiologic approach to the evaluation of wrist injury and to present two acute cases of rare CMC dislocations.

Imaging of the postoperative knee.

On sagittal images after anterior cruciate ligament (ACL) reconstructions, the femoral tunnel aperture should be at the junction of the line drawn along the posterior femoral cortex and the line drawn along the roof of the intercondylar notch (Bluemensaat line). The tibial tunnel aperture should be in the anterior portion of the second third, i.e. anterior aspect of the middle of the tibial epiphysis. An inaccurate placement of the femoral tunnel affects the graft isometry. A tibial tunnel too anteriorly placed results in intercondylar notch roof impingement. After meniscus surgery, first-line MRI is often sufficient to diagnose new tears; however, sometimes it is necessary to perform CT arthrography or MR arthrography. Surgical cartilage repair is evaluated based on articular congruity and on the appearance of the subchondral bone.

Diagnosing pelvic osteomyelitis beneath pressure ulcers in spinal cord injured patients: a prospective study.

There is no consensus on a diagnostic strategy for osteomyelitis underlying pressure ulcers. We conducted a prospective study to assess the accuracy of multiple bone biopsies and imaging to diagnose pelvic osteomyelitis. Patients with clinically suspected osteomyelitis beneath pelvic pressure ulcers were enrolled. Bone magnetic resonance imaging (MRI) and surgical bone biopsies (three or more for microbiology and one for histology per ulcer) were performed. Bacterial osteomyelitis diagnosis relied upon the association of positive histology and microbiology (at least one positive culture for non-commensal microorganisms or three or more for commensal microorganisms of the skin). From 2011 to 2014, 34 patients with 44 pressure ulcers were included. Bacterial osteomyelitis was diagnosed for 28 (82.3%) patients and 35 (79.5%) ulcers according to the composite criterion. Discrepancy was observed between histology and microbiology for 5 (11.4%) ulcers. Most common isolates were Staphylococcus aureus (77.1%), Peptostreptococcus (48.6%) and Bacteroides (40%), cultured in three or more samples in 42.9% of ulcers for S. aureus and ≥20% for anaerobes. Only 2.8% of ulcers had three or more positive specimens with coagulase-negative staphylococci, group B Streptococcus, and nil with enterococci and Pseudomonas aeruginosa. Staphylococcus aureus, Proteus and group milleri Streptococcus were recovered from one sample in 22.8%, 11.4% and 11.4% of ulcers, respectively. Agreement was poor between biopsies and MRI (κ 0.2). Sensitivity of MRI was 94.3% and specificity was 22.2%. The diagnosis of pelvic osteomyelitis relies on multiple surgical bone biopsies with microbiological and histological analyses. At least three bone samples allows the detection of pathogens and exclusion of contaminants. MRI is not routinely useful for diagnosis.

Hoffa's disease: a report on 5 cases.

We report the case of five patients referred to our department with Hoffa's disease: three patients were at the initial stage of the disease and the two others had reached the chronic stage. This condition is one of the less well-documented causes of pain in the anterior compartment of the knee. The pathophysiological mechanism is still unclear. It is probably caused by repetitive micro trauma resulting in inflammatory, haemorrhagic and fibrous changes to Hoffa's fat pad. The final outcome of the disease is an osteochondroma. The diagnosis is established by MRI, which demonstrates inflammation of the fat pat. At the chronic stage, a standard X-ray is sufficient to demonstrate ossification of the fat pad.

Tumors of the rib.

The authors propose a pictorial review illustrating the imaging features of chest wall tumors and their specific features that discusses the main differential diagnoses. This review is based on published information and on our own experience.

Cartilaginous tumours and calcified lesions of the hand: a pictorial review.

Cartilaginous tumours of the extremities are commonly seen in radiographs. Enchondroma is the most frequently encountered tumour. Since the vast majority of enchondromas are asymptomatic, they are typically discovered as incidental findings or along with a pathologic fracture. The authors propose a pictorial review to illustrate the imaging features of cartilaginous bone lesions of the hand and their specificities, and discuss the main differential diagnoses.

[Imaging of the postoperative knee: normal and pathologic findings]. / Le genou opéré, aspect normal et complications.

Surgical management of lesions of the knee has exponentially increased over the last several years. MRI plays a major role in postoperative follow-up and evaluation of patients with residual symptoms. Familiarity with the different surgical procedures and potential complications and knowledge of normal and abnormal postoperative MRI findings are essential for evaluation of the postoperative knee. The main purpose of this article is to review the postoperative imaging features of ligaments, menisci and cartilage of the knee joint since these MRI features may lead the surgeon to consider repeat surgery.

[MR imaging of the hands in rheumatoid arthritis]. / Comment faire une IRM des mains dans la polyarthrite rhumatoïde?

MRI of the hands in patients with rheumatoid arthritis is becoming routine. It is therefore necessary to develop simple standardized protocols providing fast imaging. It is best to image both hands simultaneously, from distal radioulnar to proximal interphalangeal joints, using a surface coil. Three imaging features are evaluated: synovitis, marrow edema and erosions. These can be quantified with the 'RAMRIS' score based on T1-weighted, fat-suppressed T2-weighted and fat-suppressed contrast material enhanced T1-weighted sequences in 2 planes (coronal and axial). Dynamic imaging provides improved evaluation of synovial inflammation.

[Langherans' cell histiocytosis: a case report]. / Histiocytose X: à propos d'un cas.

Langherans' cell histiocytosis is rare in adults. It should be considered in patients with lytic osseous lesions with sclerotic rim especially when involvement of adjacent soft tissues is present.

[Foraminal, epidural and intravertebral migration of a calcified degenerated intervertebral disk]. / Migration de calcifications d'un disque intervertébral dorsal dégénératif, dans l'espace épidural, le foramen et le corps vertébral.

The authors report a case of inflammatory back pain associated with radiculopathy secondary to degenerative disk calcifications migrated within the foramen, epidural space and vertebral body. The purpose of this clinical case is to illustrate this uncommon cause of radiculopathy and avoid unnecessary invasive diagnostic procedures.

[MRI study before and after extracorporal shock wave therapy in calcifying tendinitis of the shoulder]. / Etude IRM avant et aprEs lithotritie des tendinopathies calcifiantes de l'épaule.

PURPOSE: Extracorporal shock wave therapy has recently been proposed with good results (70%) for treatment of persistent painful calcifying tendinitis of the shoulder. The aim of this study was to evaluate the early impact of shock wave therapy on the anatomic structures of the shoulder. MATERIALS AND METHODS: Eight patients (7 women and 1 man, with mean age of 48 years) were prospectively followed up after undergoing shock wave therapy (1500 pulses with 0.28 mJ/mm2 energy). MRI (T1: 500/12 [TR/TE] and STIR: 7200/60/180/180 [TR/TE/TI/alpha]) were obtained 2 hours before and 15 days after the procedure; in addition for 5 of them one more examination was carried out 6 hours after extracorporal shock wave therapy. RESULTS: There was no significant signal change of the humeral bone or rotator cuff, and the calcification size, when seen (6 times), was unchanged at successive MR examinations. One patient had subcutaneous fat signal change (STIR) next to the zone of impact, which resolved 15 days after the extracorporal shock wave therapy. No bursitis or joint effusion was found. CONCLUSION: Shock wave therapy has no early complications or significant impact on the anatomic structures of the shoulder.