The work was devised to compare measurements of glomerular filtration rate (GFR) by technetium-99m-diethylenetriaminepentacetic acid (^99mTc-DTPA) renogram to those by creatinine clearance (measured and predicted by Cockroft and Gault) and by inulin clearance. A total number of 65 individuals were enrolled: 15 healthy controls and 50 patients with renal disease. Compared to inulin clearance used as the gold standard, ^99mTc-DTPA overestimated at low and underestimated at high GFRs. ^99mTc-DTPA measurements were less precise than creatinine clearance except for individuals with GFR >100 ml/min × 1.73 m². Measured creatinine clearance had the highest correlation coefficient with inulin clearance, ^99mTc-DTPA clearance the lowest. In correlation analyses, 81.5% of the interindividual variability for measured creatinine clearance could be explained by true differences in inulin clearance; this value dropped to 59.1 and 57.4% for predicted creatinine clearance and ^99mTc-DTPA, respectively. In patients with GFR <25 ml/min × 1.73 m², all ^99mTc-DTPA measurements were out of the 95% confidence interval for the inulin measurement. It can be inferred that ^99mTc-DTPA clearance from the renogram is less precise than measured and predicted creatinine clearance.

BS and LS are 2 accurate techniques for the diagnosis of small bowel CD, and their combined use can be recommended as an early diagnostic approach to patients in which the disease is suspected. SBE remains the best procedure for the definition of the location and extension of the disease.

The combination of octreotide and interferon is well tolerated and can be recommended for the treatment of advanced MTC.

Pulmonary disease of unknown etiology is a potentially fatal complication in patients with lysinuric protein intolerance (LPI), an autosomal recessive disorder caused by the defective transport of cationic amino acids. Lung involvement was investigated in nine Italian LPI patients through pulmonary function tests and lung imaging studies consisting of conventional chest radiography, high-resolution computed tomography (HRCT), and perfusion and ventilation scintigraphy. One 10-yr-old patient died of severe respiratory insufficiency from alveolar proteinosis. All of the remaining patients were asymptomatic at the time of the study, although HRCT scans revealed signs of lung involvement defined by the presence of acinar nodules, inter- and/or intralobular thickening of the interstitial septa, and subpleural cysts in five of the patients. Radioisotope studies showed an uneven distribution of perfusion and ventilation, and confirmed the presence of segmental and/or diffuse pulmonary functional defects. No abnormalities of pulmonary function were evident, and answers to a questionnaire excluded primary coexisting lung disease. In patients with LPI, including those without clinical and functional impairment, HRCT and radioisotopic studies appear to be the most sensitive methods for the early diagnosis of lung disease and correct assessment of its progression.

We report on tests of a radionuclide imaging system for in vivo investigations in small animals with low-energy photons as from 125 I (27-35 keV). Imaging optics features a high-resolution coded aperture mask and a fine pitch hybrid pixel detector (silicon 300-m or 700-m thick, or CdTe 1 mm thick) of the Medipix2 series (55 m pitch, 256 256 pixels). The coded aperture had 480 70-m holes in 100-m-thick tungsten. Laboratory tests with a 109 Cd 22 keV source and a microfocus X-ray tube (35 kVp, Mo anode) show a system resolution of about 110 m at magnification = 2 12 and a sensitivity improvement of 30:1 as compared to a 300-m pinhole collimator. The field of view also depends on magnification: in the experiments presented, it varied from 6 mm ( = 2 12) to 21 mm ( = 0 66). 125 I in vivo mouse thyroid imaging with the 70 m coded aperture, a 300 m pinhole and a 100 m parallel hole collimator was also performed to obtain a qualitative comparison. This low energy, semiconductor-based, compact gamma-ray imaging system can be used as a gamma-ray sub-millimeter resolution imager for energies below about 35 keV and it is the basic imaging unit of a small animal Single Photon Emission Computed Tomography system (MediSPECT) built at University of Napoli Federico II and Istituto Nazionale Fisica Nucleare (INFN), Napoli.