الفهرس 
The peritoneum Anatomical considerationOnly 14 pages are availabe for public view
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Abstract
As surgical and chemotherapeutic strategies in peritoneal carcinomatosis evolve, imaging needs to provide better resolution over the entire peritoneal surface in order to identify small implants and diffuse disease.
PET/CT can be used as a problem-solving tool in the identification of recurrence, but its achievable spatial resolution only approaches 5 mm. DW-MRI is an increasingly promising method, with a capability of visualizing lesions as small as 2 mm.
In contrast to PET/CT, DW-MRI does not involve ionizing radiation, is widely available (no extra hardware is needed), and is less time-consuming.
DW-MRI may be useful in selective cases in imaging shortly after surgery, where the specificity of PET is reduced, in order to differentiate an inflammatory lesion from a rapidly regrowing tumor. It may also be applied for whole-body imaging, where thin slice acquisition and potent fat suppression permit precise maximum intensity projection reconstructions with high signal-to-noise ratio, resulting in a three dimensional display of areas of impeded diffusion, which may serve as a screening or staging tool of malignant dissemination. DW-MRI data must be interpreted in conjunction with conventional anatomical imaging to avoid-false-positives.
Imaging modalities in peritoneal carcinomatosis and their clinical performance:
Ultrasound has a sensitivity of 69% and a specificity of 93%. The advantages of ultrasound in peritoneal carcinomatosis detection are excellent spatial resolution in superficial tissues, superior specificity and no ionizing radiation but it is operator-dependent and has reduced sensitivity in deep lesions and in the absence of ascites.
CT has a sensitivity of 85–93% and a specificity of 82%. The advantages of CT in peritoneal carcinomatosis detection are wide availability, good reproducibility, high cost-efficiency and fast scanning times but it is ionizing radiation, suboptimal sensitivity in subcentimeter lesions and certain anatomical locations.
MRI has a sensitivity of 52–96% and a specificity of 80–92%. The advantages of MRI in peritoneal carcinomatosis detection are improved accuracy, no ionizing radiation but it is relatively high cost, time-consuming and does not give any information about the functional activity of the tumor.
DW-MRI has a sensitivity of 84–90%and a specificity of 91–95%.The advantages of DW-MRI in peritoneal carcinomatosis detection are improved sensitivity on a per lesion basis and in problematic areas with a potential for quantitative assessment of response to treatment but it needs correlation with conventional MRI to avoid false-positive findings, quantification may be hampered by small size of lesions.
PETCT has a sensitivity of 78–97%and a specificity of 55–90%.The advantages of PETCT in peritoneal carcinomatosis detection are whole body coverage, improved sensitivity particularly in detection of occult relapse, semiquantitative assessment of treatment response but it is ionizing radiation, limited availability, high cost, reduced sensitivity in small and diffusely infiltrative lesions and possibly certain histological subtypes and false-positive uptake in inflammatory lesions.