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Evaluation and Treatment of a Ureterosciatic Hernia Causing Hydronephrosis and Renal Colic
Abstract An 87-year-old female presented with complaints of intermittent severe right renal colic. CT imaging demonstrated a ureterosciatic hernia and moderate hydronephrosis proximal to the portion of the ureter that was herniated through the sciatic foramen. A retrograde pyelogram demonstrated a transition point in the ureter at the location of the hernia. A ureteral stent was placed resulting in straightening of the ureter, resolution of hydronephrosis, and complete resolution of the patient's symptoms
Steps in Semiautomated Image Analysis
<p>Semiautomated image analysis involves recognition and automated segmentation of each lymph node (A), quantitation of magnetic tissue parameters (T2*, variance of pixel values; [B]), comparison of extracted tissue parameter to a database (C), and 3D reconstruction of nodal anatomy onto vascular anatomy (D).</p
Breast Cancer Mapping
<div><p>Patient with breast cancer prior to sentinel lymph node biopsy.</p>
<p>(A) Conventional axillary MRI shows nonenlarged lymph nodes that do not meet the size criteria of malignancy (white bar = 5 mm).</p>
<p>(B) Following intravenous administration of nanoparticles, a single 3-mm intranodal metastasis was correctly identified.</p>
<p>(C) Ex vivo MRI of sentinel node specimen confirms metastasis.</p>
<p>(D) Semiautomated nodal analysis and reconstruction correctly juxtaposed solitary lymph node metastases adjacent to two normal lymph nodes.</p>
<p>(E) Correlative histopathology confirms the diagnosis. For 3D reconstruction of axillary nodal anatomy see <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.0010066#pmed-0010066-s002" target="_blank">Video S2</a>.</p></div
Tissue Parameters in Learning Dataset
<p>Nodal tissue parameters for benign and malignant nodes are shown before (A and B) and after (C–E) intravenous administration of magnetic nanoparticles. Note the insensitivity of conventional MRI (A and B), better separation using single-value analysis (C and D) and excellent separation using two-value analysis (E).</p
Utility of a New Bolus-Injectable Nanoparticle for Clinical Cancer Staging1
AbstractBACKGROUND: In this study, we report on the use of a new, bolus-injectable, carboxymethyl dextran-based magnetic nanoparticle (MNP), ferumoxytol, to improve detection in loco-regional lymph nodes by magnetic resonance imaging (MRI). Methods: This preliminary study was performed as a prospective, single-center, open label pilot study to determine the magnitude of nodal MRI signal changes and to determine the optimal time points for imaging following intravenous (IV) bolus injection of the MNP. The study group consisted of 10 patients, all of whom were diagnosed with prostate cancer before any systemic therapy. RESULTS: All 10 patients had lymph nodes evaluated by histopathology. Of the evaluated 26 lymph nodes, 20 were benign and 6 were malignant. The mean short-axis diameter of benign lymph nodes was 6 mm and the mean short-axis diameter of malignant lymph nodes was 7 mm. Following IV administration, there was a significant change in mean signal-to-noise ratio (SNR) of benign lymph nodes (P < .0001) whereas there was little change in the mean SNR of malignant nodes (P = .1624). No adverse events were encountered. CONCLUSION: Ferumoxytol is safe and, at the appropriate circulation interval, modulates nodal signal intensity, allowing for identification of malignant nodal involvement by MRI
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