ABSTRACT
<p><b>OBJECTIVE</b>To investigate the magnetic resonance (MR) signal features of superparamagnetic iron oxide (SPIO) with different particle size and concentration.</p><p><b>METHODS</b>The superparamagnetic iron oxide with different concentration and particle size was scanned by magnetic resonance; T1, T2 and T2(*) values of each group were recorded to evaluate the features of MR signals.</p><p><b>RESULTS</b>The T1 value of SPIO with different particle size had negative linear relationship with concentration. In low concentration the T2 and T2(*) values were elevated markedly with the particle size decreased; while in high concentration the T2 and T2(*)values were elevated gently with particle size decreased. lg(T2), particle size and concentration of SPIO had linear relationship.</p><p><b>CONCLUSIONS</b>SPIO affects magnetic resonance signal mainly with effect on T1 and T2. T2 value can be regarded as the major detection index in the magnetic resonance scan of SPIO. There is a linear relationship among particle size, SPIO concentration and lg(T2) value.</p>
Subject(s)
Humans , Contrast Media , Pharmacology , Dose-Response Relationship, Drug , Ferrosoferric Oxide , Chemistry , Pharmacology , Image Enhancement , Magnetic Resonance Imaging , Methods , Magnetite Nanoparticles , Chemistry , Particle SizeABSTRACT
Objective To evaluate the value of stereotactic core needle biopsy(SCNB)in diagnosis of breast lesions.Methods Forty-seven cases were punctured with computer-assisted stereotactic system, spring-loaded biopsy guns and 16 G core needles.The record of each item was collected,including clinical manifestations,descriptions of the mammographic characteristics(such as calcification,mass and architectural distortion),the pathology of the SCNB and the surgical pathology or mammographic follow-up data.Then the results of SCNB were analyzed based on the comparison of SCNB pathology and the surgical pathology.The reason that SCNB failed and misdioagnosed was inferred from the relationship of SCNB accuracy and the X-ray characteristics.Results Forty-four cases were punctured successfully,3 cases failed.Thirty-one patients were operated soon after biopsy.The results of 27 SCNB cases agreed well with the final pathology but the other 4 did not.Conclusions SCNB as an accurate,time-saving and cost- effective method,is also minimally invasive and hardly changes the architecture of the breast.SCNB can diagnose breast lesions in advance,reduces the number of surgical biopsy,and is promising in clinical application.