Venous thrombosis: a mimic of musculoskeletal injury on MR imaging.

Clinical signs and symptoms of venous thrombosis and musculoskeletal pathologies frequently overlap. Sometimes, patients with venous thrombosis undergo MR examinations under an equivocal suspicion of muscle, tendon or articular injury. A low pretest clinical suspicion and lack of familiarity with the conventional MR imaging signs of venous thrombosis may result in failure to diagnose venous thrombosis, delaying treatment and raising morbimortality. In MR imaging, thrombosis presents as venous ectasia with intraluminal heterogeneous content. Small vein thrombosis is often identified as having a branching aspect. Perivenous edema and inflammatory soft tissue changes may be the most prominent findings. The purpose of this paper is to illustrate MR findings of venous thrombosis in patients who underwent MR examinations due to suspected musculoskeletal pathologies. Cases of venous thrombosis in different sites of the body diagnosed through MR are presented.

Modulation of Matrix Metalloproteinase 14, Tissue Inhibitor of Metalloproteinase 3, Tissue Inhibitor of Metalloproteinase 4, and Inducible Nitric Oxide Synthase in the Development of Periapical Lesions.

INTRODUCTION: Periapical cysts and granulomas are chronic lesions caused by an inflammatory immune response against microbial challenge in the root canal. Different cell types, cytokines, and molecules have been associated with periapical lesion formation and expansion. Therefore, because of the chronic inflammatory state of these lesions, the aim of this study was to evaluate the in situ expression of matrix metalloproteinase (MMP)-14 and -19, tissue inhibitor of metalloproteinase (TIMP)-3 and -4, CD68, and inducible nitric oxide synthase (iNOS) in periapical cysts and granulomas. METHODS: Sixteen cases of periapical cysts and 15 cases of periapical granulomas were analyzed. Ten normal dental pulps were used as the negative control. Immunohistochemistry was performed with anti-MMP-19, anti-MMP-14, anti-TIMP-3, anti-TIMP-4, anti-iNOS, and anti-CD68 antibodies. RESULTS: The expression of TIMP-3, TIMP-4, iNOS, and CD68 was significantly higher in both the cyst and granuloma groups than in the control group. TIMP-4 was also significantly higher in cases of chronic apical abscess. There was also a significant difference in the expression of MMP-14 between the cyst and control groups. However, there were no differences in the expression of MMP-19 between the 3 groups. CONCLUSIONS: Our data suggest that the expression of MMP-14, TIMP-3, and TIMP-4 is associated with the development of periapical lesions.