Improved Outcomes in Colon and Rectal Surgery part 13. Written by many of the worlds leading colorectal surgeons, this evidence-based text investigates the risks and benefits of colorectal surgeries. By using clinical pathways, algorithms, and case discussions, the authors identify the best practices for patient safety and positive outcomes to ensure that physicians correctly recognize potential problems and carefully manage complications | IMPROVED OUTCOMES IN COLON AND RECTAL SURGERY Figure Appendix Mucocele. Axial MDCT demonstrates distension of the appendix with mucus. Figure Lipoma. Axial MDCT demonstrates a 2-3 cm round sharply defined tumor with homogenous fat density -80 to -120 H adherent to the sigmoid colon. CTA has become the method of choice for imaging the pulmonary vasculature and has replaced invasive pulmonary angiography as the reference standard for diagnosis. 112-117 Another advantage of CTA over pulmonary angiography is the ability to identify alternative or additional diagnosis such as atelectasis pneumonia pulmonary edema pleural and pericardial effusions and many others. CT venography CTV combined with CTA can be used as a comprehensive examination of the deep venous system to detect both PE and deep vein thrombosis DVT . CTV is performed by scanning of the pelvis from the iliac crest to the popliteal fossa approximately 120 s after completion of the CTA. CTV could potentially salvage the occasional suboptimal PE study by diagnosing a DVT and guide interventions such as vena cava filter placement. Numerous studies have cited 97 agreement between CTV and US. 118-122 The addition of CTV increases the gonadal radiation exposure and should be used selectively on the basis of risk-benefit considerations . avoided in young patients and reproductive female patients . 116 Appendix Acute Appendicitis MDCT has a high sensitivity 91-100 and specificity 9199 in diagnosing acute appendicitis 123-126 . The diagnosis of acute appendicitis is based on finding an abnormally dilated 6 mm enhancing appendix appendix surrounded by inflammatory periappendiceal fat stranding focal thickening of the base of the cecum periappendiceal abscess or obstructing calcified appendicolith Figures and . The most common reason for a false-negative diagnosis is related to a paucity of intraabdominal fat often seen in pediatric patients and patients with a lean body habitus. 127-130 .
