Download or read book MRI Assessment for Soft Tissue Reactions in Relation to High Level of Cobalt and Chromium Metal Ions Released from Metal on Metal Hip Implants written by Raheef Alatassi and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Objectives: This study was conducted to determine the local and systemic effects of elevated blood levels of cobalt (Co) and chromium (Cr) on adverse local tissue reactions (ALTRs), aseptic lymphocyte-dominant vasculitis-associated lesion (ALVAL), metallosis and cardiotoxicity.Methods: We conducted two independent retrospective studies on two separate groups of patients in a single center in Quebec. To determine the local effects of elevated blood levels of Co and Cr, we retrospectively reviewed 47 patients with metal-on-metal (MoM) painful hip arthroplasties and multiple Metal Artefact Reduction Sequence Magnetic Resonance Imaging (MARS MRI) to identify the patients with positive ALTR lesions. The volume progression of pseudotumors was assessed on consecutive MARS MRI images using the Hart classification. Blood Co and Cr ions were recorded. Any indications for revisions were also noted.Separately, to determine the systemic (cardiac) effect of the elevated Co and Cr levels we retrospectively reviewed ten patients with unilateral MoM bearing hip implant having a minimum two years follow and abnormal level of metal ions in blood. All patients were without history of any cardiac (normal electrocardiography and cardiac markers) and renal conditions. Blood metal ion and cardiac markers level were recorded for all patients. The deposition of Co and Cr ions in the heart was determined using cardiac MRI, and cardiac markers including brain natriuretic peptide (BNP) and Troponin-1 (trop-1) were determined.Results: From all reviewed patients, we have identified 20 patients with positive ALTR lesions. The mean age of the patients and mean follow duration was 65.4 years (range: 54.7 to 85.4 years) and 8.3 months, respectively. Eight hip arthroplasties showed increased lesion size6 | P a g e(5 with class 2b, 2 with class 2a and 1 with class 1), ten hips had revision surgery of which six had increased levels of Co and Cr. A significant positive relationship was identified between the level of Co ions and the volume and size progression of the lesions.For the systemic effects, a separate ten patients who had no cardiac and renal history were included in the study. The mean age of the patients was 54.90 ± 4.25 years old. Co and Cr levels ranged from 0.72 to 141.4 ug/L (mean of 43.23 ± 57.03 ug/L) and from 0.89 to 88.3 ug/L (mean of 27.78 ± 34.07 ug/L), respectively. Although a significantly positive correlation was observed between the presence of pericardial effusion and Cr levels, no other significant correlations were determined between blood metal ion levels and the cardiac parameters. Correlation for left ventricular mass was not computed since all patients had normal findings.Conclusion: A higher Hart classification showed a tendency to increase or maintain their sizes compared to those of lower classification. Elevated of blood Co levels (but not chromium) are correlated with the volume and size progression of the lesions. Lesions type 2b and 3 have a more aggressive behaviour. Bigger lesions tend to grow, and smaller lesions can regress or can remain stable for a longer time. ALTRs associated with metal on polyethylene (MoP) are rare but are usually aggressive. On the other hand, there is no concrete evidence that elevations in the blood Co and Cr levels can cause cardiotoxicity. Thus, the absolute presence of elevated metal ions is insufficient to cause cardiac disease on the patient"--