Alessandro Campari

Extravasation of Radiographic Contrast Media: Prevention, Diagnosis, and Treatment

Contrast media extravasation represents a not unusual problem in radiological practice. Incidence, patient-, and procedure-related risk factors, pathogenesis, and clinical manifestations of extravasation injuries are discussed with a review of recent literature, and a practical preventive approach is proposed. A diagnostic and therapeutic protocol, to be applied whenever contrast extravasation is detected, includes radiographic assessment of compartmentalization, antidote application, local care, and clinical follow-up; indications for surgical consultation and adverse event reporting are provided.

Common and unusual diseases involving the iliopsoas muscle compartment: spectrum of cross-sectional imaging findings

Although relatively uncommon, many different infectious, hemorrhagic and neoplastic disease processes may involve the iliac and psoas muscles and are increasingly diagnosed especially in referral hospitals. Furthermore, the iliopsoas compartment may become injured during trauma, percutaneous instrumentation, laparoscopic or open surgical procedures. State-of-the-art cross-sectional imaging including volumetric multidetector CT and multiplanar MRI acquisitions allows prompt detection, comprehensive visualization and confident characterization of most iliopsoas lesions, and the possibility to guide percutaneous biopsy and drainage. The pertinent regional anatomy is reviewed in correlation with disease pathways and imaging modalities. Neoplastic lesions, purulent and mycobacterial iliopsoas infections are discussed with examples. Imaging plays the key role in the differentiation of primary versus secondary abscesses due to intestinal, urinary and musculoskeletal infections, that determines medical therapy and surgical need. The iliopsoas compartment may become involved through direct extension by retroperitoneal, skeletal and pelvic tumors, and should be carefully scrutinized when reviewing oncologic imaging studies since it represents one of the preferred sites of skeletal muscle metastatization. Iliopsoas hemorrhages due to trauma, aortic aneurysms and anticoagulation are reviewed, with a special focus on determining whether the bleeding comes from aneurysmal rupture or from coagulopathy, a critical differentiation to decide about medical or surgical treatment. Postoperative complications involving the iliopsoas compartment are discussed with examples, including retroperitoneal bleeding, infections, urinary leaks and collections following various surgical or instrumentation procedures. Emphasis is placed on choosing the correct imaging modality and technique, particularly to detect active bleeding or urine leakage, and to reduce artifacts related to presence of metallic implants.

Vascular Map Combined with CT Colonography for Evaluating Candidates for Laparoscopic Colorectal Surgery

Contrast-enhanced computed tomography colonography (CE-CTC) is a useful guide for the laparoscopic surgeon to avoid incorrectly removing the colonic segment and the failure to diagnose of synchronous colonic and extra-colonic lesions. Lymph node dissection and vessel ligation under a laparoscopic approach can be time-consuming and can damage vessels and organs. Moreover, mesenteric vessels have extreme variations in terms of their courses and numbers. We describe the benefit of using an abdominal vascular map created by CE-CTC in laparoscopic colorectal surgery candidates. We describe patients with different diseases (colorectal cancer, diverticular disease, and inflammatory bowel disease) who underwent CE-CTC just prior to laparoscopic surgery.

Common and unusual urogenital Crohn's disease complications : spectrum of cross-sectional imaging findings

Involvement of the urinary tract and genital organs is not uncommon in patients affected with Crohn’s disease (CD). Occurring in both sexes, uro-gynecological complications are often clinically unsuspected because of the dominant intestinal or systemic symptoms. Knowledge of their manifestations and cross-sectional imaging appearances is necessary to recognize and report them, since correct medical or surgical treatment choice with appropriate specialist consultation allows to prevent further complications. Besides uncomplicated urinary tract infections that usually do not require imaging, urolithiasis and pyelonephritis represent the most commonly encountered urinary disorders: although very useful, use of computed tomography (CT) should be avoided whenever possible, to limit lifetime radiation exposure. Hydronephrosis due to ureteral inflammatory entrapment and enterovesical fistulization may result from penetrating CD, and require precise imaging assessment with contrast-enhanced CT to ensure correct surgical planning. Representing the majority of genital complication, ano- and rectovaginal fistulas and abscesses frequently complicate perianal inflammatory CD and are comprehensively investigated with high-resolution perianal MRI acquired with phased-array coils, high-resolution T2-weighted sequences and intravenous contrast. Finally, rare gynecological manifestations including internal genital fistulas, vulvar and male genital involvement are discussed.

Comprehensive MRI diagnosis of sacral osteomyelitis and multiple muscle abscesses as a rare complication of fistulizing Crohn's disease

Pelvic osteomyelitis is a very uncommon complication of Crohns disease, usually clinically unsuspected in the setting of acute Crohns disease relapses. The case of a 21-year old patient is reported, in whom ileo-cecal inflammatory disease was complicated by fistulization to the presacral space and sacral osteomyelitis, plus multiple abscesses involving the iliopsoas, posterior paravertebral and gluteal muscles. As confirmed by surgical and pathological findings, MRI provided comprehensive imaging diagnosis by demonstrating both the pathogenesis and the full extent of the complex, deep pelvic inflammatory process. Low back pain in patients with Crohns disease should not be underestimated since its differential diagnosis includes serious and potentially life-threatening causes such as osteomyelitis, so prompt assessment with cross sectional imaging, particularly MRI, is necessary.

MRI Study Protocol

Focused MRI of the anus and perianal region should be performed on high- magnetic-field scanners operating at 1–1.5 T. Acquisition using 1.5-T clinical equipment is recommended but (as our experience confirms) a 1.0-T scanner is adequate, although it does pose disadvantages in terms of the duration of the exam [1].

Imaging Techniques and Expected Post-colonoscopy Appearances

Optical colonoscopy represents the diagnostic and therapeutic gold standard for most colonic pathologies, including screening for colorectal cancer and removal of polyps. Although in the last years alternative techniques have been developed in order to improve patient tolerance to colonoscopy, it remains associated with potential pain and discomfort and still has a risk for morbidity and mortality. Following diagnostic or therapeutic colonoscopy, imaging may be requested to investigate suspected iatrogenic complications, particularly perforation and haemorrhage. After endoscopy, radiographic and CT imaging generally show gaseous distension, absence of faeces and possible air–fluid levels of the large bowel. Metallic clips may be observed after endoscopically control of post-polypectomy bleeding. The post-polypectomy electrocoagulation syndrome (PPES) is characterised by focal colonic wall thickening and adjacent peritoneal inflammation in absence of perforation, demonstrated by CT imaging after polypectomy with electrocautery. Clinically, PPES closely mimics signs and symptoms of colonic perforation, but is a self-limiting condition which is amenable to a conservative therapy. Radiologists’ awareness of this entity and CT differentiation from perforation are crucial to obviate unnecessary invasive treatments. A typical case of PPES is presented.

Imaging Appearances of Post-colonoscopy Complications

Optical colonoscopy carries a low but real risk for morbidity and mortality, which increases as endoscopy assumes a more therapeutic role. Adverse event rate is about 0.3 % and almost 85 % of serious complications occur in patients undergoing polypectomy. Perforation and haemorrhage, the commonest specific complications, may be unrecognised during the procedure. Furthermore, clinical symptoms and laboratory signs often develop late; therefore, prompt adequate imaging is mandatory in case of clinical suspicion. Plain radiographs have limited sensitivity in detection of pneumoperitoneum and extraperitoneal gas. Multidetector computed tomography (CT) represents the best technique to assess free air or fluid, colonic injuries and bleeding.

Hepato-Bilio-Pancreatic Complications of Ulcerative Colitis

Extraintestinal manifestations (EIMs) occur in up to 30 % of patients affected by IBD. Hepato-bilio-pancreatic (HBP) complications are one of the most common EIM and primary sclerosing cholangitis (PSC) is by far the most important condition associated. ERCP has been considered for years the gold standard for the diagnosis of PSC. Imaging demonstration of diffuse, multifocal strictures and irregularities involving the medium-sized intrahepatic and/or medium or large-sized extrahepatic ducts is the gold standard for this diagnosis. Nowadays MRCP represents a valid alternative to ERCP depicting bile ducts in their natural degree of distension, using as contrast medium the bile itself. As a consequence, strictures, biliary sludge and stones, which normally may limit studies with contrast medium, do not limit the evaluation of bile ducts with MRCP. Furthermore, MRCP is a less expensive technique, avoiding ionizing radiation and anaesthesia. Other less common HPBs are: autoimmune pancreatitis, IgG4 associated cholangitis, small ducts PSC and CCA. CCA is a fearful and relatively common complication of PSC and the distinction between a benign dominant stricture and CCA in a PSC patient is challenging. Cholangiographic features that suggest CCA include irregular high grade ductal narrowing, rapid progression of the strictures, marked ductal dilatation proximal to strictures, and presence of polypoid lesions.