Shape and volume of internal anal sphincter showed by three-dimensional anorectal ultrasonography.

PURPOSE: The aim of this work is to characterize the shape and the volume of the internal anal sphincter (IAS) in normal subjects by three-dimensional anorectal ultrasonography. METHODS: Thirty-nine normal volunteer males (mean age 58.5 ± 18.7) and 25 females (mean age 59.4 ± 14.1) were submitted to anorectal ultrasonography. The tissue is defined by a semiautomatic procedure. Measurements of thickness, length and volume were assessed automatically. The software provides an average number of 57,600 thickness measurements, 360 length measurements for each zone (90 for each quadrant) and seven volume measurements (one for each anatomical area).The mean values of magnitudes were calculated for the entire volume in each quadrant and zone. Age and gender-related variations were analyzed. RESULTS: In assessments of the whole tissue, only thickness was gender-related, with greater thickness for females (male thickness: 1.81 ± 0.47 mm, female thickness 2.16 ± 0.57 mm, P-value<0.01).In the distal zone: thickness, length and volume were all larger in females (for male and female respectively: 1.83 ± 0.49 mm vs 2.34 ± 0.58 mm, P-value<0.01, for the thickness; 10.87 ± 2.10mm vs 12.18 ± 2.21 mm, P-value<0.02 for the length and 1501 ± 605 mm(3) vs 2169 ± 871 mm(3), P-value<0.01 for the volume). In the medial zone, only thickness was gender-related, with greater thickness in females (male thickness: 2.04 ± 0.60mm, female thickness:2.44 ± 0.74 mm, P-value<0.02).The only variation observed in the proximal zone concerned length, larger in males (respectively: 11.27 ± 2.84 mm vs 9.55 ± 2.43 mm, P-value<0.02). The male population was significantly positively correlated with ageing for volume in the whole tissue (ρ = 0.32, P-value<0.05), and for both thickness and volume in the medial zone (ρ = 0.33, P-value<0.05 for thickness; ρ = 0.39, P-value<0.02 for the volume). CONCLUSION: This new method is useful to understand both functional anal disorders and local damage which may affect only part of the muscle tissue.

Software for hepatic vessel classification: feasibility study for virtual surgery.

PURPOSE: The detection and classification of hepatic vessels in diagnostic images are essential for hepatic pre-surgery planning. Our team has developed a tool for classification, analysis, and 3D reconstruction of the hepatic and portal systems. METHODS: Our software first extracts a graphic representation of a set of connected voxels, representing both systems. It then calculates two binary volumes representing the main part of the two venous systems. Finally, it combines these results to obtain the correct vessel classification. RESULTS: Segmentation steps are semi-automatic and require about 40 min to complete. Schematization and classification steps are automatic and require about 17 min for results. CONCLUSION: The software provides a correct and detailed reconstruction even where pathologies have caused morphological and geometrical variations in the vessels. The time required for the entire procedure is compatible with clinical requirements, providing an efficient tool for diagnosis and surgical planning.

In vivo investigation of hepatic iron overload in rats using T2 maps: quantification at high intensity field (4.7-T).

In vivo quantitation of hepatic iron content is useful in diagnosis and staging of several iron related diseases. We used an experimental model of hepatic iron overload to determine the correlation between iron content and T2 relaxation time in rat liver. Experiments were carried out at 4.7T for high signal-to-noise ratio (SNR) using a spin-echo multiecho sequence with six echoes and minimum echo-time of 5.5 msec. The liver iron content was determined ex vivo by atomic absorption spectrophotometry (AAS). T2 maps were calculated in order to evaluate the space distribution of the iron content. We found good linear correlation between the in vivo liver transversal relaxation rate and the iron content within the range explored (106-4538 microg Fe/g liver wet wt.). T2 maps revealed that the decrease in T2 is not homogeneous through the liver parenchyma. This finding represents a physiological limitation to obtaining better correlation between T2 and iron content.

Pre-operational survey of a U mine near Val Vedello, Italy.

Results obtained from radiometric research carried out from 1980-81 in the region of U mines in the Val Vedello are provided. Data are presented on 222Rn, 226Ra and natural U concentrations in spring and surface waters. Concentrations were found to be relatively low. There is some increase in the vicinity of the exploratory U mine but this is, at least up to the present, only of a local character. Data are presented on external gamma exposure, 210Pb and 210Po in foodstuffs and in the urine of normal and exposed population as well as 226Ra in milk and vegetable samples. The aim of this study is to outline a preliminary map of natural radioactivity on the site before starting the mining activity. This will enable us later to detect changes caused by the U mining, milling and mill-tailing disposal operations.