Comparison of Cr-EDTA and Tc-DTPA for glomerular filtration rate measurement.

Purpose: The production of Cr-labelled ethylenediaminetetraacetic acid (Cr-EDTA), a validated and widely used radio-isotopic tracer for glomerular filtration rate (GFR) measurement in Europe, was recently halted by the manufacturer. Technetium-99m-diethylenetriaminepentaacetic acid (Tc-DTPA) clearance has so far mostly been restricted to assessment of separate renal function by scintigraphy, but scarcely used and validated for GFR measurement. We compared the performances of Cr-EDTA and Tc-DTPA for GFR and extracellular fluid measurement.

Equivalent Dose Rate 1 Meter from Neuroendocrine Tumor Patients Exiting the Nuclear Medicine Department After Undergoing Imaging.

I-metaiodobenzylguanidine (MIBG) and In-pentetrotide SPECT have been used for functional imaging of neuroendocrine tumors (NETs) for the last 2 decades. More recently, PET/CT imaging with F-FDG, F-fluorodihydroxyphenylalanine (FDOPA), and Ga somatostatin-receptor ligands in NETs has been expanding. A literature search could find no direct measurements of the dose rate from NET patients exiting the nuclear medicine department after undergoing PET/CT with F-FDOPA or Ga-DOTATOC, a somatostatin analog.

Identification of a rectal subregion highly predictive of rectal bleeding in prostate cancer IMRT.

Background And Purpose: To identify rectal subregions at risks (SRR) highly predictive of 3-year rectal bleeding (RB) in prostate cancer IMRT.

Materials And Methods: Overall, 173 prostate cancer patients treated with IMRT/IGRT were prospectively analyzed, divided into "training" (n=118) and "validation" cohorts (n=53). Dose-volume histograms (DVHs) were calculated in three types of rectal subregions: "geometric", intuitively defined (hemi-rectum,…); "personalized", obtained by non-rigid registration followed by voxel-wise statistical analysis (SRRp); "generic", mapped from SRRps, located within 8×8 rectal subsections (SRRg).