Vascular anomalies of the large bowel

Vascular anomalies of the large bowel, commonly known as vascular malformations of the colon (VMC), constitute a rare but important condition, potentially causing significant morbidity and mortality. Our aim is to provide an up-to-date, practical summary evaluating this disease entity, focussing on pathogenesis, as well as diagnostic and therapeutic modalities. We reviewed available data in the literature, and discussed it in the form of a narrative, readily applicable review. Most VMC (over 70%) are detected in the caecum and ascending colon, and affect people aged over 50 years. VMC are almost always symptomatic, presenting with lower bleeding. Endoscopy is crucial to identify and locate VMC, and to treat the lesions. In patients who fail or do not fit endoscopic treatment, aggressive approaches (interventional angiology or surgery) are mandatory. Up to 40% of patients may have relapse in the long term. VMC are rare but potentially life-threatening. Advances in endoscopic imaging and therapy have improved the results of treatment. Long-term follow-up after treatment is recommended.

Vascular anomalies of the large bowel

INTRODUCTION

Vascular anomalies of the large bowel, commonly referred to as vascular malformations of the colon (VMC) constitute a rare but important condition, potentially causing significant morbidity and mortality. Our aim is to provide an up-to-date, practical summary evaluating this disease entity, focussing on pathogenesis, as well as diagnostic and therapeutic modalities.

MATERIALS AND METHODS

We reviewed available data in the literature, and discussed it in the form of a narrative, readily applicable review.

RESULTS

Most VMC (over 70%) are detected in the caecum and ascending colon, and affect people aged over 50 years. VMC are almost always symptomatic, presenting with lower bleeding. Endoscopy is crucial to identify and locate VMC, and to treat the lesions. In patients who fail or do not fit endoscopic treatment, aggressive approaches (interventional angiology or surgery) are mandatory. Up to 40% of patients may have relapse in the long term.

CONCLUSIONS

VMC are rare but potentially life-threatening. Advances in endoscopic imaging and therapy have improved the results of treatment. Long-term follow-up after treatment is recommended.

High field functional MRI

Functional magnetic resonance imaging (fMRI) has become the most widely used approach for studying brain functions in humans. The rapid and widespread diffusion of fMRI has been favoured by the properties this technique presents, and particularly by its sensitivity in analysing brain functional phenomena and by the lack of biological invasiveness, resulting in an unprecedented and unparalleled flexibility of use. These properties of fMRI brought the functional examination of the brain within the reach of the whole neuroscience community and have appreciably stimulated the research on the functional processes of the living brain. Among the main features of fMRI, its spatial and temporal resolution represents clear advantages compared with the other methods of functional neuroimaging. In fact, the high spatial resolution of fMRI permits to produce more precise and better localised information, and its temporal resolution provides the potential of a better understanding of neural dynamics at the level of single functional areas and of the neural constituents of functional patterns. A fundamental possibility of improving spatial and temporal resolution without excessively degrading signal-to-noise ratio consists in the use of high magnetic field intensity fMRI units. Besides, high field units make the use of more demanding fMRI paradigms, like single trial event related studies, much more compatible with the need of a solid statistical evaluation. This has notably promoted the diffusion of high field MRI units for human studies throughout the world, with very high field MRI units, up to 8 T, working in a few research centres, and a larger number of MRI units with field intensity ranging between 3 and 5 T.

The prevalence of HCV infection in a cohort of pregnant women, the related risk factors and the possibility of vertical transmission

The prevalence of antibodies for one or more HCV antigens was 2.3% of 1,347 mothers at childbirth. Compared with the principal factors studied, the presence of antibodies was more frequent in women who were carriers of HIV infection (3/3), in those who had suffered liver diseases (5/37) or who had had transfusion (3/25). This was as opposed to women who did not have any risk factor (p < 0.001). The prevalence of HCV-RNA was 1.3%; in relation to the antibody state, such a condition was more frequent in subjects with antibodies for 3 or 4 antigens (about 80%) compared with those who were positive for 1 or 2 antigens. HCV-RNA of the same genotype as the mother (type 1; 1a) was also found in the funicular blood of 2 of the 18 babies born to mothers who were positive for HCV-RNA. In the course of the follow-up (from the 3rd to the 18th month) the viral RNA was not found in any of the babies, nor was it found in the 2 who were positive at birth. Even the antibodies gradually disappeared, although slowly. At the 10th month, 91% of the babies resulted as having no antibodies and at the 18th month none of the babies resulted as having antibodies. Breast-feeding also appeared to have no influence on the transmission of the infection; out of 18 viremic mothers indeed 12 (67%) breast-fed their babies.