Publications by authors named "O L Villegas-Medina"

Objective: We sought to study the normal enhancement patterns seen on MRIs of the epiphysis, physis, and metaphysis and age-related vascular changes in piglets using gadoteridol, a nonionic gadolinium chelate.

Materials And Methods: We quantitatively and qualitatively analyzed the normal changes on sequential T1-weighted images after the IV administration of gadoteridol. In an investigation approved by the research animal care committee at our hospital, we studied the proximal and distal femurs of 26 piglets 1-6 weeks old and correlated the enhanced images with findings on intermediate-weighted, T2-weighted, and gradient-recalled echo images and at histologic examination.

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Purpose: To evaluate the use of magnetic resonance (MR) imaging during manual positioning of the hip, or multipositional MR imaging, in an open-magnet configuration to study femoral head containment, articular congruency, and femoral head deformity in Legg-Calvé-Perthes disease.

Materials And Methods: In 12 children with advanced Legg-Calvé-Perthes disease, multipositional MR imaging and conventional arthrography were compared in the assessment of containment, femoroacetabular congruency, and femoral head deformity. Images of the hips in several positions were compared subjectively and objectively.

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Objective: We describe gadolinium-enhanced MR imaging of position and vascular enhancement of the femoral head in pediatric patients who have undergone reduction of hip dislocation.

Subjects And Methods: Within 24 hr of hip reduction and spica casting, we performed 25 gadolinium-enhanced MR studies in 18 infants and young children (15 girls, three boys) with 23 dysplastic hips. All but two patients underwent closed reductions.

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Purpose: To determine if gadolinium-enhanced MR imaging can detect early reversible ischemia of the capital femoral epiphysis and physis induced by hip hyperabduction in piglets.

Materials And Methods: Thirteen 1- to 3-week-old piglets were placed in maximal bilateral hip abduction and then studied with dynamic gadolinium-enhanced MR imaging 1-6 hr later to assess ischemia of the 26 femoral heads. The piglets were then allowed to ambulate freely for 1 or 7 days and reimaged in neutral position to assess reperfusion.

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Purpose: To evaluate the magnetic resonance (MR) imaging appearance of cartilaginous abnormalities in Legg-Calvé-Perthes (LCP) disease and their association with growth arrest.

Materials And Methods: Twenty-seven MR images and radiographs of 25 hips in 23 patients were reviewed for epiphyseal, physeal, and metaphyseal abnormalities. Follow-up radiographs (mean time, 20.

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