Imaging of Spondylodiscitis: A Comprehensive Updated Review-Multimodality Imaging Findings, Differential Diagnosis, and Specific Microorganisms Detection.

Spondylodiscitis is defined by infectious conditions involving the vertebral column. The incidence of the disease has constantly increased over the last decades. Imaging plays a key role in each phase of the disease. Indeed, radiological tools are fundamental in (i) the initial diagnostic recognition of spondylodiscitis, (ii) the differentiation against inflammatory, degenerative, or calcific etiologies, (iii) the disease staging, as well as (iv) to provide clues to orient towards the microorganisms involved. This latter aim can be achieved with a mini-invasive procedure (e.g., CT-guided biopsy) or can be non-invasively supposed by the analysis of the CT, positron emission tomography (PET) CT, or MRI features displayed. Hence, this comprehensive review aims to summarize all the multimodality imaging features of spondylodiscitis. This, with the goal of serving as a reference for Physicians (infectious disease specialists, spine surgeons, radiologists) involved in the care of these patients. Nonetheless, this review article may offer starting points for future research articles.

Ultrasound patterns of localized cutaneous leishmaniasis and clinical correlations.

A single-center retrospective study reviewed the following sonographic features of 18 confirmed cases of localized cutaneous leishmaniasis to identify shared presentation patterns: echotexture, lesion borders, hypodermal involvement, soft-tissue changes, and vascular pattern. A second objective was to correlate these patterns with clinical characteristics, including sex, age, anatomical location, nodule vs. plaque presentation, raised borders, granulation tissue, swelling, hyperkeratotic crusting, disease onset, and healing time. Two main patterns were identified with high-frequency ultrasonography. The first pattern was characterized by a high level of inflammation and deep hypodermal involvement, while the second variant showed involvement limited to the dermis, with minimal inflammation. The "inflammatory pattern" showed ill-defined borders, mixed echotexture, prominent vascularity with central distribution, and was correlated with clinical signs of ulceration, granulation tissue, raised borders, and longer healing time (p < 0.05). The "pauci-inflammatory pattern" presented a well-defined structure with decreased echogenicity, reduced or absent vascularity with minimal soft-tissue changes, and was associated with a shorter healing time (p < 0.05).

Magnetic resonance imaging of soft tissue sarcoma: features related to prognosis.

Magnetic Resonance Imaging is a fundamental tool in the evaluation of soft tissue sarcoma. Imaging features are relevant for the assessment of treatment strategies, surgical planning and also for patients' prognosis prediction. Among soft tissue sarcoma and also other malignancies, the size of the mass is usually considered the prognostic key element in diagnostic imaging. Moreover, several other features should be obtained from MRI studies with prognostic implications in all type of soft tissue sarcoma: peritumoral enhancement, signs of necrosis, deep location, ill-defined borders/signs of infiltrations. Focusing on soft tissue sarcoma subtypes, some other magnetic resonance imaging features are more specific and related to prognosis. In myxofibrosarcoma the magnetic resonance imaging "tail sign" and a "water-like" appearance on fluid-sensitive sequences, due to rich myxoid matrix content, are both associated with higher risk of local recurrence after surgical excision; nevertheless, the "tail sign" is also related to a higher risk of distant metastases at diagnosis. The "tail sign" is associated with higher risk of local recurrence after surgical excision in undifferentiated pleomorphic sarcoma as well. In patients affected by synovial sarcoma, the "triple sign" identifiable in magnetic resonance imaging (T2w sequences) is associated with decreased disease-free survival and indicates the simultaneous presence of solid cellular elements (intermediate signal intensity), hemorrhage or necrosis (high signal intensity) and fibrotic regions (low signal intensity). In addition, absence of calcifications are associated with reduced disease-free survival in patients affected by synovial sarcoma. Signal heterogeneity is associated with worst prognosis in all type of soft tissue sarcoma, particularly in myxoid liposarcoma. In recent years, several new quantitative tools applied on magnetic resonance imaging have been proved to predict patients' prognosis. Above all the new tools, radiomics seems to be one of the most promising, and, has been proved to have the capability in discriminating low-grade from high-grade soft tissue sarcomas. Therefore, magnetic resonance imaging studies in patients with soft tissue sarcoma should be accurately evaluated and their results should be taken into account for prognostic assessment.

MRI Features as Prognostic Factors in Myxofibrosarcoma: Proposal of MRI Grading System.

RATIONALE AND OBJECTIVES: Myxofibrosarcoma (MFS) is a common soft tissue sarcoma in the elderly patients with both clinical and magnetic resonance imaging (MRI) peculiar features: very high recurrence rate, relatively low risk of distant metastases. On MRI it shows an infiltrative pattern ("tail sign") and high myxoid matrix content with water-like appearance on fluid-sensitive sequences. Due to these unusual characteristics, we propose a specific MRI grading system to stratify the risk of local recurrence (LR) and offer other prognostic information. MATERIALS AND METHODS: Two expert radiologists retrospectively and blindly reviewed preoperative MRI of 150 patients affected by MFS of the extremities treated at a single Institution. Myxoid matrix component and contrast enhancement of the tumor were evaluated and graded with a semiquantitative method. The presence of an infiltrative pattern, the depth of the tumor (deep and/or superficial) and tumor sizes were also recorded. MRI features were analyzed separately and correlated to LR risk, sarcoma specific survival and distant metastases rate. Then, according to the statistical significance of the correlation between MRI features and prognosis a 3-grade scoring system was proposed and evaluated to assess the risk of LR. RESULTS: Mean age was 66.1 ± 14.4 years; mean follow-up was 16 ± 28.3 months. The MRI features most associated with higher risk of LR resulted to be: lesion sizes (both volume and maximum diameter with a cut-off of 20 cm - p = 0.01), the "tail sign" (p = 0.045), and high myxoid matrix content with MRI water-like appearance (p = 0.0493). Ninety-four patients (94 of 150- 62.7%) were grade 1, 33 (22.0%) grade 2, and 23 (15.3%) grade 3. Interobserver agreement was substantial with K= 0.779 (95%CI 0.685-0.874). Higher grades of MRI grading system proposed were significantly associated with an increased LR risk, hazard ratio = 2.031 (95%CI 1.366-3.019; p < 0.001). CONCLUSION: This is the largest series evaluating MRI features as prognostic factors for MFS. The MRI grading system proposed is significantly able to stratify the risk of LR in MFS of the extremities. The system is applicable to all the standard MRI studies protocols, might help in surgical planning, and may offer prognostic information.

Myxofibrosarcoma: Clinical and Prognostic Value of MRI Features.

Myxofibrosarcoma is one of the most common soft tissue sarcomas in the elderly. It is characterized by an extremely high rate of local recurrence, higher than other soft tissue tumors, and a relatively low risk of distant metastases.Magnetic resonance imaging (MRI) is the imaging modality of choice for the assessment of myxofibrosarcoma, which plays a key role in the preoperative setting of these patients. MRI features associated with the high risk of local recurrence are: high myxoid matrix content (water-like appearance of the lesions), high grade of contrast enhancement and presence of an infiltrative pattern ("tail sign"). On the other hand, MRI features associated with worse sarcoma specific survival are: large size of the lesion, deep location, high grade of contrast enhancement. Recognizing the above-mentioned imaging features of myxofibrosarcoma may be helpful in stratifying the risk for local recurrence and disease-specific survival. Moreover, the surgical planning should be adjusted according to the MRI features.