One stage or two stage treatment of colorectal cancer associated to abdominal aortic aneurysm: morbidity and mortality.

The coexistence of colorectal cancer and abdominal aortic aneurysm has been observed with increasing frequency, raising several questions about therapeutic and surgical strategies for management of both diseases. This study has reviewed 440 cases (359 cases analyzed) of colorectal cancer associated with abdominal aortic aneurysm recovered in the literature from year 1987 to 2010. In 120 cases, patients were treated in one stage; in 239 cases, they were treated in two stages. The treatment in two stages was associated with a morbidity of 26.4%, with a mortality of 5% and prosthetic infection of 0.8%. The treatment in one stage had rates of complications and mortality of 13.3% and 4.2% respectively and no cases of prosthetic infection. Analysis of the literature shows that the treatment in two stages exposes patients to a higher risk of complications and prosthetic infection.

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.

New method for internal anal sphincter measurements: feasibility study.

PURPOSE: The aim of this paper is to provide a method for measuring the internal anal sphincter on the basis of the quantitative analysis of three-dimensional endosonographic images. A software calculates a large set of measurements which are able to describe the three-dimensional shape of the muscle. METHODS: A software provides four types of measurements: thickness, length, area and volume. The different magnitudes are estimated using the same reference system. The measurements obtained are modeled by functions that describe their spatial trend. The precision and reproducibility of the method was tested on a phantom before a study was performed on fifteen healthy patients. The measurements were carried out by two different operators. The inter-observer variability were assessed. RESULTS: In the phantom measurements the mean errors and the standard deviation were: 0.05 +/- 0.1 mm for the thickness, 0.02 +/- 0.12 mm for the length, -4.43 +/- 2.4 mm(2) for the area, -20.69 +/- 20.83 mm(3) for the volume. The maximum absolute differences between the measurements carried out by the two operators was: 0.18 mm for the thickness (in the 95% of the case), 1.69 mm(2) for the area (in the 95% of the case), and 0.25 mm for the length, and 29.46 mm(3) for the volume. The human IAS assessments were evaluated on each segment. The mean of the all tissue measurements carried out were (mean +/- SD): 1.71 +/- 0.34 mm for the thickness, 33.24 +/- 6.10 mm for the length, 111.28 +/- 29.08 mm(2) for the area. The mean of the volume measurements of the entire tissue was: 4124 +/- 1160 mm(3). Inter-observer variability was observed only in the anterior proximal segment for the thickness measurements by Wilcoxon's signed rank test (P value = 0.048) and for the volume assessments by the limits of agreement method (-118 to 78 mm(3)). The mean percentage errors and the limit of agreement for the measurements of the entire tissue were: 0.27 and (-0.11 to 0.12 mm) for the thickness, -2.32 and (-3.88 to 2.33 mm) for the length, -0.05 and (-9.71 to 9.83 mm(2)) for the area, -1.89 and (-366 to 240 mm(3)) for the volume. CONCLUSION: The assessments of accuracy and precision of the method result satisfactory for all four type of measurements. The reproducibility analysis confirms very good inter-observer agreement for the phantom measurements and for the most part of the IAS segments evaluations. Inter-observer variability was seen only for the thickness and volume measurements of the anterior-proximal segment. Our method provides a high number of measurements with good accuracy enabling a very detailed study of IAS morphology.

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.