(BQ) Part 2 book Gastrointestinal imaging presents the following contents: Focal liver disease, gallbladder, pancreas, bile ducts, spleen, multisystem disorders and syndromes, peritoneum, mesentery and abdominal wall.
Section VIII Focal Liver Disease CHAPTER 60 Cystic Hepatic Tumors Jin-Young Choi, Guilherme Moura da Cunha, Beatriz C Baranski Kaniak, and Claude B. Sirlin A Simple Hepatic Cysts and Polycystic Liver Disease Definition Simple hepatic cysts are benign developmental epitheliumlined lesions that contain serous fluid and not communicate with the biliary system Autosomal dominant polycystic liver disease is an inherited disorder characterized by cyst formation in several organs, including the liver Demographic and Clinical Features Simple hepatic cysts are present in at least 2.5% of adults and are more frequent in women They are usually detected incidentally Hepatic cysts can be solitary or multiple Over 90% are asymptomatic; rarely symptoms may arise owing to compression of bile ducts or other adjacent structures Most hepatic cysts are sporadic, but can also occur in association with autosomal dominant (AD) polycystic hepatorenal disease About 40% of patients with AD polycystic hepatorenal disease with renal involvement have hepatic cysts; 15% of affected patients have multiple hepatic cysts but no radiographically identifiable renal cysts AD polycystic liver disease is usually asymptomatic Rarely advanced disease manifests with painful hepatomegaly, abdominal protuberance and discomfort, hepatic dysfunction, compromised pulmonary function from diaphragmatic compression, and, as a result of vascular compression, presinusoidal portal hypertension or Budd-Chiari syndrome Pathology Histologically, hepatic cysts are lined with a single layer of cuboidal epithelium, identical to that of bile ducts, and a thin rim of fibrous stroma Although the pathogenesis of hepatic cysts is not known, it is believed that they are congenital/developmental in origin, resulting from progressive dilation of biliary microhamartomas that failed to develop normal connections with the biliary tree AD polycystic liver disease is part of the fibropolycystic liver disease spectrum, which includes bile duct hamartoma, Caroli disease, and congenital hepatic bfibrosis The diseases in this spectrum all are caused by congenital bile duct malformation In AD polycystic liver disease, innumerable well-defined cysts are present, usually in both lobes of the liver These cysts are histologically identical to hepatic cysts and their pathogenesis is thought to be similar Imaging Features On all imaging modalities, cysts are sharply marginated, round or ovoid in shape, contain simple-appearing fluid, and show no or only a few thin (equal to or less than 2 mm) septations The presence of multiple, thick (equal to or greater than 3 mm), irregular, or nodular septations or internal debris suggests a neoplastic or infectious process and warrants a more aggressive workup On ultrasound, cysts are sonolucent with posterior acoustic enhancement and imperceptible walls (Figure 60-1) At unenhanced CT, cysts are homogeneously hypoattenuating; after intravenous administration of contrast, the cyst wall and its content not enhance (Figure 60-2) At MRI, cysts are homogeneously hypointense onT1-wighted images and homogeneously and markedly hyperintense (“light bulb” appearance) on T2-weighted images (Figure 60-3) Heavily T2-weighted images accentuate the apparent hyperintensity of the cyst relative to the surrounding liver Owing to T2 shine-through, cysts may be mildly hyperintense on Figure 60-1 Longitudinal ultrasound image shows two hepatic cysts (arrows) in the liver One is 3.5 cm in diameter and the other is 1.8 cm Notice imperceptible walls, posterior acoustic enhancement, and absence of internal echoes 371 372 Gastrointestinal Imaging (A) (B) (C) (D) Figure 60-2 Hepatic cyst at CT Dynamic CT images before (A) and, after contrast administration, in the late hepatic arterial (B), portal venous (C), and 3-minute delayed (D) phases The liver cyst (arrow) is homogeneously hypoattenuating on the unenhanced image It does not enhance on any of the postcontrast images Its wall is imperceptible diffusion-weighted sequences (Figure 60-3) Enhancement does not occur after administration of contrast agents Hepatic cysts are rarely complicated by intracystic hemorrhage or inflammation; such cysts may have lowlevel echoes at ultrasound, intermediate to high attenuation at CT, and heterogeneous signal intensity at both T1-and T2-weighted imaging Fluid-fluid levels may be visible when mixed blood products are present Complicated cysts may also have septations, slightly thickened walls, and mural calcifications Such cysts may be indistinguishable at imaging from cystic neoplasms The appearance of AD polycystic liver disease is identical to that of sporadic hepatic cysts except that the cysts in polycystic liver disease are much more numerous (Figure 60-4), are more likely to be hemorrhagic, and— depending on their size, number, and location—may cause narrowing of portal veins, hepatic veins, or inferior vena cava In cases complicated by venous obstruction, intrahepatic collateral vessels may be observed The liver drained by compressed hepatic veins may be congested and show a heterogeneous (“nutmeg”) enhancement pattern after the administration of contrast Differential Diagnosis ■ Hydatid cyst: History to exposure to dogs and sheep; patients typically come from endemic areas Cysts are encapsulated and frequently show “eggshell” peripheral calcifications; daughter cysts on the inside of the main cyst are usually seen C y s t i c H e p a t i c Tu m o r s (A) (B) (C) (D) (E) (F) (G) (H) (I) (J) Figure 60-3 Hepatic cyst at MRI A 76-year-old woman with a 6.5-cm hepatic cyst Dynamic T1-weighted MR images at 3T were acquired before (A) and after administration of gadobenate in the late hepatic arterial (B), portal venous (C), 3-minute delayed hepatobiliary (D), and 60-minute delayed hepatobiliary (E) phases The cyst’s wall (white arrow) is imperceptible and does not enhance on any of the postcontrast images Notice excretion of contrast material into the bile duct in the hepatobiliary phase (black arrow in E); as cysts not communicate with the biliary tree, there is no enhancement of the cyst’s lumen Relative to liver, the cyst is hypointense on T1-weighted (F) and markedly hyperintense on T2-weighted (G) images It is markedly hyperintense on a b = 0 s/mm2 (H) image and, owing to T2 shine-through, minimally hyperintense on a moderately diffusion-weighted b = 500 s/mm2 image (I) The cysts has a high apparent diffusion coefficient (J) Abscess: Encapsulated cystic mass with surrounding edema; patients typically have fever and an elevated white count ■ Biliary cystadenoma: Encapsulated cystic mass with numerous septations typically diagnosed in a middleaged woman ■ Cystic metastasis: Seen in the presence of a known malignancy; typically has an enhancing irregular rim of viable neoplastic tissue ■ (A) Management/Clinical Issues The presence of thick, irregular, or nodular septations or debris suggests a neoplastic or infectious process and warrants a more aggressive workup Cysts complicated by hemorrhage or inflammation may be difficult to differentiate from cystic neoplasms Intracystic hemorrhage is more frequently encountered in polycystic liver disease than in sporadic hepatic cysts Rarely patients with AD polycystic liver disease require surgical intervention (B) Figure 60-4 CT of autosomal dominant polycystic liver disease (A and B) shows cysts of the kidneys as well as the liver 373 374 Gastrointestinal Imaging (fenestration, marsupialization, resection, transplant) for relief of symptoms; imaging helps in surgical planning by demonstrating the size, extent, and distribution of the cysts as well as their effects on vessels, ducts, and other adjacent structures Key Points ■ Hepatic cysts are common benign developmental lesions while AD polycystic liver disease is an inherited disorder involving several organs ■ A simple hepatic cyst is characterized by a round or ovoid lesion with no perceptible wall or, after the administration of contrast, enhancement ■ Hepatic cysts not communicate with the biliary tree ■ The presence of thick, irregular, or nodular septations or debris suggests a neoplastic or infectious process and warrants a more aggressive workup Biliary cystadenoma is considered premalignant; about 10% of lesions have dysplastic or borderline malignant histologic features Biliary cystadenocarcinoma is malignant but relatively unaggressive Local invasion or distant metastasis is uncommon, and long-term survival can be achieved after complete surgical resection Definition Biliary cystadenoma and biliary cystadenocarcinoma are rare multilocular cystic tumors of biliary origin Biliary cystadenomas and cystadenocarcinomas only rarely communicate with the biliary tree Pathology Grossly, biliary cystadenoma and biliary cystadenocarcinoma are globular and have smooth surfaces The tumors usually are large, ranging in size from 1.5 to 35 cm, and almost always multilocular The multilocularity is a key feature that differentiates them from hepatic cysts The locules usually contain mucinous fluid Bloody fluid is unusual but may be observed in biliary cystadenoma undergoing malignant change A well-defined, thick fibrous capsule lines the tumor This capsule may contain calcifications Mural nodules and papillary excrescences are seen in both biliary cystadenoma and biliary cystadenocarcinoma but are more common and tend to be larger in biliary cystadenocarcinoma At microscopy, the tumor wall comprises three layers: an inner layer of biliary-type cuboidal or columnar nonciliated epithelium, a middle layer of moderately to densely cellular stroma, and a dense outer layer of collagenous connective tissue Biliary cystadenoma is classified into two histologic subtypes depending on the type of cellular stroma: cystadenoma with mesenchymal ovarian-like stroma and cystadenoma with hyaline stroma Carcinoma arising in cystadenoma with hyaline stroma is more aggressive, and the presence of ovarian-like stroma is considered a favorable prognostic indicator About 10% of biliary cystadenomas have signs of dysplasia or borderline malignancy Dysplastic changes include foci of epithelial atypia, loss of polarity, and mitotic activity Features of malignant transformation include severe architectural atypia, exophytic papilla, and cellular anaplasia and pleomorphism When malignant transformation occurs, it is usually of papillary or tubular-papillary type Demographic and Clinical Features Biliary cystadenoma and biliary cystadenocarcinoma are rare, account for less than 5% of all hepatic cystic neoplasms, and have an estimated prevalence of in 20,000 to 100,000 and in 10 million, respectively Biliary cystadenoma shows a strong female predominance (90% occur in women); however, biliary cystadenocarcinoma does not appear to have a gender predilection Discovery typically occurs in middle-aged adults Patients may be asymptomatic or may complain of intermittent pain or biliary obstruction Although these lesions are usually intrahepatic (85%), extrahepatic locations have been described Imaging Features At ultrasound, both biliary cystadenoma and biliary cystadenocarcinoma are cyst-like multilocular, hypoechoic lesions with internal septa (Figure 60-5) Small nodules may stud the cyst wall At CT and MRI, they appear as solitary well-defined encapsulated cystic masses Internal septa, mural nodules, and, at CT, capsular calcifications may be evident Depending on hemorrhage and protein content, cystic fluid may have variable signal intensity on both T1- and T2-weighted images Polypoid, pedunculated projections are characteristic of biliary cystadenocarcinoma, but these excrescences can be seen in cystadenomas without malignant transformation Thus imaging does Further Reading Mortele KJ, Peters HE Multimodality imaging of common and uncommon cystic focal liver lesions Semin Ultrasound CT MR 2009;30:368–386 Mortele KJ, Ros PR Cystic focal liver lesions in the adult: differential CT and MR imaging features RadioGraphics 2001; 21:895–910 Federle MP, Brancatelli G Imaging of benign hepatic masses Semin Liver Dis 2001;21:237–249 B Biliary Cystadenoma and Cystadenocarcinoma C y s t i c H e p a t i c Tu m o r s (A) (B) (C) (D) Figure 60-5 Ultrasound of a biliary cystadenoma arising in a 55-year-old woman (A, B, C, and D) show a 6-cm multiloculated cystic mass with internal septa arising from left lobe of the liver In this case, no mural nodules are identified The mass was misinterpreted as a complex cyst not allow accurate differentiation between biliary cystadenoma and cystadenocarcinoma Moreover, the classic imaging features described here may be subtle, and these lesions may be mistaken for hepatic cysts at imaging (see Figures 60-5; Figure 60-6) Differential Diagnosis ■ Hemorrhagic cyst: The most challenging differential diagnosis of biliary cystadenoma is hemorrhagic hepatic cyst, in which imaging may depict internal clots as papillary excrescences and pseudonodules Pseudonodules associated with hemorrhagic cysts usually not enhance after the administration of contrast ■ Hepatocellular carcinoma: These may have necrotic components and appear cystic Hypervascularity of the solid components suggests the diagnosis of hepatocellular carcinoma ■ Cholangiocarcinoma: A variant of cholangiocarcinoma, intraductal papillary cholangiocarcinoma, may appear as a cystic mass with mural nodule ■ Undifferentiated embryonal cell carcinoma: Although embryonal cell carcinoma usually occurs in childhood, the tumor may present in adulthood ■ Cystic metastasis: This is typically is not encapsulated and a primary malignancy is typically known at the time of detection Management/Clinical Issues Biliary cystadenoma is a premalignant tumor and has a propensity for malignant degeneration Noninvasive imaging does not reliably differentiate biliary cystadenoma from cystadenocarcinoma Biopsy is relatively contraindicated owing to the risk of cyst content spillage and extrahepatic seeding Moreover, because of variability in tumor sampling, fine-needle aspiration cannot reliably exclude malignancy and is not helpful in making the diagnosis For these reasons, lesions thought to represent biliary cystadenoma or biliary cystadenocarcinoma should be completely resected It is often difficult to distinguish biliary cystadenoma from a complicated hepatic cyst Resection rather than imaging follow-up is generally curative and avoids the possibility of subsequent malignant degeneration Key Points ■ Rare, multilocular cystic tumors of biliary origin ■ Characteristic imaging findings include a thick capsule, mural nodules, and internal septations ■ Noninvasive imaging does not reliably differentiate biliary cystadenoma from cystadenocarcinoma ■ Characteristic imaging features may be subtle, and these lesions may be mistaken for hepatic cysts ■ Need surgical resection ■ Most biliary cystadenomas occur in the middle-aged women 375 376 Gastrointestinal Imaging (A) (B) (C) (D) Figure 60-6 Contrast-enhanced CT images (same patient as in Figure 60-5) (A) show a 6-cm hypoattenuating mass arising from the liver Subtle mural thickening (arrow) was unnoticed and the mass was misinterpreted as a hepatic cyst CT performed for unrelated reasons 3 months (B) and 1 year (C) later show interval development of a small extramural nodule (arrow) at the site of mural thickening; this nodule was unnoticed Two years later, the patient presented with acute abdominal pain due to spontaneous intralesional hemorrhage CT now showed a 10-cm mass (D) The mural nodule (arrow) had grown slightly The perihepatic fat was stranded, presumably as a reaction to the hemorrhage The lesion was resected and confirmed to be a biliary cystadenoma Further Reading Mortele KJ, Peters HE Multimodality imaging of common and uncommon cystic focal liver lesions Semin Ultrasound CT MR 2009;0:368–386 Mortele KJ, Ros PR Cystic focal liver lesions in the adult: differential CT and MR imaging features RadioGraphics 2001; 21: 895–910 Choi BI, Lim JH, Han MC, et al Biliary cystadenoma and cystadenocarcinoma: CT and sonographic findings Radiology 1989; 171:57–61 C Von Meyenberg Complexes Definition Von Meyenberg complexes (VMCs), also known as biliary hamartomas, are benign cystic lesions derived from malformed bile ducts and surrounded by a variable amount of fibrous stroma They not communicate with the biliary tree Demographic and Clinical Features The prevalence of VMCs has been estimated at about 1% to 5% in autopsy series VMCs are considered part of the congenital hepatic fibrocystic disease spectrum and may coexist with other manifestations of this spectrum, such as Caroli disease or congenital hepatic fibrosis Nevertheless they usually occur as isolated finings VMCs are usually asymptomatic and discovered incidentally at imaging Their clinical importance is that they can be misinterpreted at imaging as hepatic metastases C y s t i c H e p a t i c Tu m o r s (A) (B) Figure 60-7 Von Meyenberg complexes at contrast-enhanced CT in the portal venous (A) and 3-minute-delayed (B) phases are seen as innumerable hypoattenuating nodules in the right lobe of the liver The lesions are of uniform size but some are slightly irregular in shape Pathology VMCs are congenital bile duct malformations caused by failure of embryonic involution At gross pathology, the lesions appear as multiple black or gray-white to gray- yellow nodules scattered across the hepatic parenchyma They are well defined, irregular in shape, and relatively uniform in size; (A) the majority measure less than 5 mm, although they may range up to 15 mm in diameter Microscopically, VMCs are malformed (dilated, tortuous, or branching) bile ducts lined by a single layer of cuboidal epithelium and surrounded by fibrocollagenous stroma They not communicate with the biliary tree (B) Figure 60-8 Von Meyenberg complexes at MRI Axial T2-weighted (A) and, in the hepatobiliary phase, a gadoxetate-enhanced T1-weighted image (B) demonstrate innumerable lesions throughout the liver The vast majority are smaller than 5 mm; the largest is 12 mm (arrow) Many are irregularly shaped The hepatobiliary-phase image demonstrates no communication with the biliary tree 377 378 Gastrointestinal Imaging Imaging Features On ultrasound, VMCs have a variable appearance; they may be hypoechoic, hyperechoic, or heterogeneous The variability in appearance is thought to reflect the lesions’ underlying structure, comprising malformed bile ducts embedded in a fibrocollagenous stroma The presence of multiple “comet-tail” echoes within a liver lesion is considered a unique ultrasound feature of VMCs These echoes are attributed to sound-beam reverberation caused by cholesterol crystals within the cystically dilated bile ducts Unenhanced CT shows multiple hypoattenuating cystic hepatic nodules (Figure 60-7) At MRI, VMCs are hypointense relative to liver parenchyma on T1-weighted images and strongly hyperintense on T2-weighted images (Figure 60-8) MR cholangiography shows no communication of the lesions with the biliary tree Although hepatic cysts have a smooth contour, VMCs tend to have a more irregular contour at both CT and MRI (see Figures 60-7 and 60-8) The lesions usually not enhance in the arterial phase after administration of contrast agents, although smooth, uniform rim enhancement in the late venous phases may be observed Mural nodular enhancement has been reported but is atypical Hepatocyte-specific contrast media, such as gadoxetate, not accumulate within the lesions (see Figure 60-8) Unlike cysts and cystic metastases, VMCs tend to be uniform in size, with the vast majority of lesions measuring less than 15 mm Differential Diagnosis ■ Metastases: Rarely appear purely cystic and typically have a round to oval shape ■ Simple hepatic cysts: Cysts are variable in size and frequently larger than 1.5 cm They appear round or oval and not irregular Peribiliary cysts: Typically seen in a patient with liver cirrhosis Cysts are periportal in distribution and typically centrally located in the liver ■ Caroli disease: Saccular or fusiform dilation of the intrahepatic bile ducts communicating with the biliary system A central dot sign is typically present ■ Management/Clinical Issues VMCs are usually discovered incidentally at imaging For the radiologist, the key issue is to recognize the lesions as benign and not to mistake them for metastases Cholangiocarcinoma arising in VMCs has been reported, but this is rare; routine follow-up of patients with VMCs is not necessary Key Points ■ Benign liver cystic malformations ■ May be misinterpreted at imaging as multiple hepatic metastases Features that suggest the correct diagnosis include relative size uniformity, slight contour irregularity, marked T2 signal hyperintensity, and absence of arterial-phase enhancement Further Reading Hussain SM, Semelka RC Liver masses Magn Reson Imaging Clin North Am 2005;13:255–275 Mortele KJ, Peters HE Multimodality imaging of common and uncommon cystic focal liver lesions Semin Ultrasound CT MR 2009;30:368–386 Zheng RQ, Zhang B, Kudo M, Onda H, Inoue T Imaging findings of biliary hamartomas World J Gastroenterol 2005;11:6354–6363 728 Index Pancreas (Cont.) imaging techniques, 522–526, 522f, 524f–525f looped configuration, 521, 521f metastases, 571–574, 572f–573f multiple endocrine neoplasia syndrome, 694–696, 694f–695f normal anatomy, 521–522, 521f pancreatoblastoma, 569–571, 570f–571f pseudomass, 533, 533f sarcoidosis, 703 sigmoid configurationn, 521, 521f surgery, postoperative complications, 575–576, 575f–577f transplantation surgery, 577–581, 577f–580f uneven lipomatosis, 532, 532f Von Hippel-Lindau (VHL) syndrome, 697–698, 698f Pancreas divisium, acute pancreatitis, 539, 539f Pancreatic duct, periampullary adenocarcinoma, 188–189, 189f Pancreatic gland, 521, 521f Pancreatic heterotopia, 528, 528f Pancreaticobiliary junction anomalies, 529, 529f normal anatomy, 522 Pancreaticoduodenectomy See also Whipple procedure pancreatic ductal adenocarcinoma, 562 procedure and postoperative management, 575–576, 575f–577f Pancreatic pseudocyst, differential diagnosis, 488, 602–603 Pancreatitis acute defined, 535 demographic/clinical features, 535–536 differential diagnosis, 540, 546 imaging classification, 535f–536f, 536–537, 537t imaging features, 537–540, 538f–541f interstitial phase, 535–537 management/clinical issues, 540–542 necrotizing phase, 535–537, 537t, 538f, 540f, 541–542 autoimmune differential diagnosis, 540, 564 imaging features, 548, 548f–549f chronic definition, 543 demographic/clinical features, 543 differential diagnosis, 546–547 imaging features, 543–546, 544f–549f management, 548–549 pathology, 543 variants, 547–548 groove pancreatitis, 547–548 differential diagnosis, 564 hereditary, 531, 531f transplant complications, 579–580 Pancreatoblastoma, 569–571, 571f Paraduodenal hernia (PDH), 126–128, 127f–129f Paraesophageal hernias, 88–90, 89f differential diagnosis, 92 Parasites small bowel, 144–145, 144f–145f splenic cysts, differential diagnosis, 602 PDH See paraduodenal hernia Pediatric End-Stage Liver Disease (PELD), liver transplantation, 361–367 Pedunculated polyps, colon, 248, 248f Pelvic floor anatomy, 290, 291f classification, 292–294 differential diagnosis, 292 imaging technique, 291–292 management/clinical issues, 294 posterior compartment imaging, 290–294 definition, 290 demographic/clinical features, 294 weakness, 268–270, 269f Pelvic hernia, 672 Pelvic organ prolapse, 292 Peptic scarring definition, 26 demographic/clinical features, 26 differential diagnosis, 29 atrophic gastritis, 62 imaging features, 26–28, 27f–28f management/clinical issues, 29–30 pathology, 26 Peptic stricture differential diagnosis, 29 achalasia, 12 eosinophilic esophagitis, 32 Schatzki ring, 44–45 management/clinical issues, 29–30 reflux esophagitis, 27–28, 28f Peptic ulcers See duodenal ulcer; gastric ulcer Percutaneous ethanol injection, hepatocellular carcinoma, 408 Percutaneous transhepatic cholangiography (PTC), bile duct, traumatic injury, 513 Perforation Crohn’s disease, 139–140, 140f diverticulitis, 234 esophagus, 40–43 gallbladder, 467–468, 468f peritonitis, 649–650, 650f Perianal fistulizing disease, 268 classification and pitfalls, 277–278 definition, 274 demographic/clinical features, 274 differential diagnosis, 277 imaging features, 274–277, 275f–277f management/clinical issues, 278 pathology, 274 Peribiliary cysts, differential diagnosis, 378 Periportal low attenuation, liver trauma, differential diagnosis, 445 Peritoneal carcinomatosis definition, 660 demographic/clinical features, 660 differential diagnosis, 656, 658, 659, 661 imaging features, 660–662, 660f–661f pathology, 660 Peritoneal cavity ascites, 640–642 imaging techniques, 633–634, 633f–634f normal anatomy, 631–633, 632f Peritoneum definition, 631 Index imaging techniques, 633–634, 633f–634f normal anatomy, 631–633, 632f primary malignancies desmoplastic small round cell tumor, 658–659, 659f malignant mesothelioma, 655–657, 655f–656f serous carcinoma, 657–658, 657f secondary tumors, 660–663, 661f–663f Peritonitis definition, 649 demographic/clinical features, 649 differential diagnosis, 650, 661 malignant mesothelioma, 656 diverticulitis, 234 imaging features, 649–650, 650f management/clinical issues, 650 pathology, 649 Pernicious anemia, type A gastritis, 61 Peutz-Jeghers syndrome, 250 definition, 683 demographic/clinical features, 683 differential diagnosis, 680, 684 imaging features, 683f–684f, 684 management/clinical issues, 684 pathology, 683–684 Pharmacobezoar, 101–102 Pharyngeal diverticula, 16–18 See also specific diverticula Pharyngeal webs, 7–8, 8f Pharyngoesophagography, overview, 3 Pharynx disorders of, 7–10 benign cysts and tumors, 8, 9f lymphoid hyperplasia, 7, 8f lymphoma, 9–10 neuromuscular disorders, 7 pharyngeal/cervical esophageal webs, 7–8, 8f radiation change, 10, 10f squamous cell carcinoma, 8–9, 9f structural disorders, 7–10 normal anatomy, 3, 4f normal pharyngeal function, 3–4 pharyngeal examination, 3, 4f Pheochromocytomas, Von Hippel-Lindau (VHL) syndrome, 697–698, 698f Phonation, pharyngeal examination, 3, 4f “Phrygian cap” gallbladder deformity, 451–452 Phytobezoars, 101–102 Pilonidal sinus, differential diagnosis, 277 Piriform sinuses neuromuscular disorders and stasis of, 7 normal anatomy, 3, 4f squamous cell carcinoma, 9, 9f Pneumatosis differential diagnosis, 638 ischemic colitis, 244–245, 245f scleroderma, 167 small bowel trauma, 173–174, 174f Pneumobilia, differential diagnosis, 493, 639 Pneumocystis, splenic abscesses and infections, 598–601, 599f–601f Pneumomediastinum, differential diagnosis, 639 Pneumoperitoneum definition, 635 demographic/clinical features, 635 differential diagnosis, 638–639 small bowel trauma, 175 imaging features, 635–637, 635f–638f management/cliinical issues, 639 scleroderma, 167 Pneumoretroperitoneum, differential diagnosis, 638, 638f Polycystic liver disease definition, 371 demographic/clinical features, 371 differential diagnosis, 372–373 imaging features, 371–372, 371f–373f management/clinical issues, 373–374 Polymyositis, pharyngeal neuromuscular disorders, 7 Polypoid adenocarcinoma, esophageal, 37–38, 38f Polypoid gastric carcinoma, differential diagnosis gastric polyps, 69 gastric varices, 95 Polypoid lymphoma, gastric lymphomas, 83, 83f Polyposis syndromes Cowden’s syndrome, 688–689 Crohkhite-Canada syndrome, 687–688 differential diagnosis, 688–689 juvenile polyposis, 686–687 Polysplenia, 589–591, 594f Porcelain gallbladder diifferential diagnosis, 458, 461 imaging features, 462f Portal hypertension accessory spleen, 589, 592f bland portal vein thrombosis, 347 cirrhosis, 323–329 gastric varices, 94 hereditary hemorrhagic telangiectasia, 339 splenomegaly, 595–596 uphill esophageal varices, 46–48, 47f Wilson’s disease, 331–332, 332f Portal hypoperfusion, transient hepatic enhancement difference, 437 Portal vein disorders bland thrombosis, 345–348 liver transplantation, 364 tumoral thrombosis, 348–353 Portosystemic shunts cirrhosis imaging, 324–326, 325f–327f hereditary hemorrhagic telangiectasia, 339 liver transplant evaluation, 362 transient hepatic enhancement difference, 436–437 Positive contrast agents, computed tomographic imaging, stomach, 53–54, 53f–54f Positron emission tomography (PET) colon imaging, 221 liver imaging, 308 pancreas pancreatic ductal adenocarcinoma, 562, 562f pancreatic endocrine tumors, 568 pancreatic imaging, 526 rectal adenocarcnioma, 282–284, 283f spleen, normal anatomy, 586 Postcholecystectomy syndrome, 465–466, 466f 729 730 Index Posterior gastric wall, gastric ulcer, 59 Postinflammatory pseudopolyps, ulcerative colitis, 228 Postnecrotic cirrhosis, 323–324 Postoperative leak liver transplant complication, 364–366 Roux-en-Y gastric bypass surgery, 103–105, 104f–105f Pouch dilatation, gastric banding, 106–107 Presbyesophagus, differential diagnosis diffuse esophageal spasm, 14 gastroesophageal reflux disease, 15 Primary achalasia demographic and clinical features, 11 imaging features, 11–12, 12f management/clinical issues, 13 pathology, 11 Primary hemochromatosis definition, 316 demographic/clinical features, 316 differential diagnosis, 322 imaging features, 320–321 pathophysiology, 317 Primary malignant melanoma of the esophagus, differential diagnosis, 38 fibrovascular polyps, 35 Primary peritoneal serous carcinoma, 657–658, 657f Primary splenic lymphoma, definition, 611 Proctitis, differential diagnosis, rectal adenocarcnioma, 284 Proctography, pelvic floor posterior compartment, 290–294, 291f–292f Progressive systemic sclerosis See scleroderma Proton-density fat traction mapping, steatosis, 312–313, 312f–313f “Prune belly” syndrome, wandering spleen, 589–591, 593f Pseudoaneurysms liver transplantation complication, 365 splenic artery, 620–625, 621f differential diagnosis, 695 “Pseudocalculus” sign, 522 Pseudocirrhosis, differential diagnosis, 327 Pseudocysts nonpancreatic, 533, 533f, 652 splenic, 602–603, 602f–603f Pseudodiverticula (Crohn’s disease), differential diagnosis, small bowel diverticulosis, 132 Pseudomass, pancreas, 533, 533f Pseudomembranous colitis definition, 240 demographic/clinical features, 236 differential diagnosis, 226, 229 diverticulitis, 234 infectious colitis, 241 ischemic colitis, 245 neutropenic colitis, 239 imaging features, 236–237, 236f–237f pathology, 236 Pseudomyxoma peritonei classification, 663 definition, 662 demographic/clinical features, 662 differential diagnosis, 619, 619f, 652, 654, 662–663 peritonitis, 650 imaging features, 662, 663f management/clinical issues, 663 Pseudopolyps, Crohn’s disease, 136 Pseudo-Zenkers diverticulum, 17 Pseydintxina peritonei, 212 Psoas abscess, Crohn’s disease, 139–140, 140f Pubococcygeal line (PCL), pelvic floor anatomy, 290–291 Pulsion diverticula, 18–20 defined, 18 demographic and clinical features, 18 imaging features, 18–19, 19f management/clinical issues, 20 pathology, 18 Purtscher’s retinopathy, acute pancreatitis, 535 Pylephlebitis, 345 Pyogenic infections bile duct, recurrent pyogenic cholangitis, 496–497, 506 liver, abscess, 430–434 splenic abscesses and infections, 598–601, 599f–601f Radiation therapy Crohn’s disease and injury from, 140 pharyngeal radiation damage, 10, 10f radiation esophagitis, 24 differential diagnosis, 29, 32 Radiofrequency ablation, hepatocellular carcinoma, 408–412, 409f–411f Reactive gastric lipomatosis, 75 Rectal adenocarcinoma definition, 280 demographic/clinical features, 280 differential diagnosis, 284 imaging features, 280–284, 281f–283f management/clinical issues, 284 pathology, 280 Rectal carcinoma, 253, 254f See also colorectal cancer Rectocele, classification, 293 Rectrorectal developmental cysts, 271–273, 272f Rectum, anatomy, 290–291, 291f Recurrent hernia, fundoplication complication, 113 Recurrent pyogenic cholangitis, bile duct, 496–498, 497f–498f Reflux esophagitis definition, 26 demographic/clinical features, 26 differential diagnosis, 29 Candida esophagatis, 21 Mallory-Weis tear, 42 viral esophagitis, 24 imaging features, 26–27, 27f management/clinical issues, 29 pathology, 26 pitfalls, 29 Regenerative nodules (RNs), hepatocellular carcinoma, 397–400, 398f–399f Renal cell carcinoma, differential diagnosis pancreatic metastases, 572, 573f small bowel metastases, 196, 197f Renomegaly, type glycogen storage disease, 331–334 333f–334f Retinal hemangioblastomas, Von Hippel-Lindau (VHL) syndrome, 697 Index RET proto-oncogene, multiple endocrine neoplasia type (MEN 2), 694–696 Right paraduodenal hernia, 126, 127f–128f differential diagnosis, 125 Ringed esophagus, eosinophilic esophagitis, 31–32, 32f Rokitansky-Aschoff sinuses, gallbladder adenomyomatosis, 471, 472f Rose thorn fistulas, 224, 225f Roux-en-Y gastric bypass (RYGB) bezoars, 101–102 definition, 103 demographic/clinical features, 103 differential diagnosis, 105 imaging features, 104–105, 104f–105f pitfalls and mimics, 105 postsurgical complications, 103–104, 104f small bowel intussusception, 163–164, 165f surgical procedure, 103, 103f–104f RYGB See Roux-en-Y gastric bypass Sacculations, scleroderma, 166 Sacrococcygeal teratoma, differential diagnosis, 271 Salmonella, infectious colitis, 240 Sarcoidosis common variants, 703 definition, 702 demographic/clinical features, 702 imaging features, 702–703, 702f–703f management/clinical issues, 704 pathology, 702 spleen, differential diagnosis, 600 Schatzki ring, 44–45, 44f–46f differential diagnosis, 44–45 Scintigraphy See nuclear scintigraphy Scirrhous carcinoma, 76–79, 77f–78f differential diagnosis atrophic gastritis, 62 gastric ulcer, 59 Scleroderma clinical features, 166 definition, 166 differential diagnosis, 167–168 small bowel diverticulosis, 132 imaging features, 166–167, 166f–168f mimics, 168 pathology, 166 pseudosacculations, Meckel’s diverticulum, 134–135 Sclerosed hemangioma, differential diagnosis, 382 Sclerosing cholangitis, bile duct differential diagnosis, 495, 497–498, 500–501, 500–502 IgG4-related, 500 primary, 499–501, 499f–500f secondary, 500 Sclerosing mesenteriitis definition, 666 demographic/clinical features, 666 differential diagnosis, 667 small bowel carcinoid tumor, 193 imaging features, 666–667, 666f–667f management/clinical issues, 668 nomenclature and classification, 667 pathology, 666 Sclerosing peritonitis, 649–650, 650f “Seat belt” sign, small bowel trauma, 175 Secondary achalasia, 11 demographic and clinical features, 11 imaging features, 11–12, 12f management/clinical issues, 13 pathology, 11 Secondary hemosiderosis definition, 316 demographic/clinical features, 316–317 differential diagnosis, 322, 334 imaging features, 320–321 pathophysiology, 318 Serous microcystic pancreatic adenoma, 556–557, 556f–557f differential diagnosis, 552, 555, 558, 568 Serous oligocystic adenoma, 557 Serpiginous small bowel defects, lipoma/hemangioma, 185–186, 185f–186f Sessile colon polpys, 247–248, 248f Shwachman-Diamond syndrome, pancreatic disease, 530, 531f Sickle cell disease secondary hemosiderosis, 318 splenic vascular disorders, 620, 624 Sigmoid esophagus, achalasia, 11–12, 12f Sigmoid mesocolon, normal anatomy, 632–633, 632f Sigmoid volvulus, 260–261, 260f Single-contrast barium enema (SCBE) colon, benign polyps, 247–248, 248f Crohn’s disease, 224, 225f diverticulitis, 231, 232f Single-contrast upper gastrointestinal studies, 51–52 Single-photon emission computed tomography (SPECT) imaging, small bowel imaging, 123, 123f Single photon emission tomography (SPECT), pancreatic imaging, 526 Sinusoidal obstruction syndrome demograpic/clinical features, 354–355 imaging features, 356, 356f–359f management/clinical issues, 359 pathophysiology, 355 Situs inversus, differential diagnosis, 125 Skip lesions, Crohn’s disease, 136–137, 137f Sleeve gastrectomy, 108–110, 109f–110f Sliding hernia, 88–90, 89f–90f Slipped fundoplication, 113 “Slow filling” hemangiomas, liver, 381 Slow transit constipation, 292 Small bowel See also Crohn’s disease anatomy, 119 benign tumors adenoma, 183–184 Brunner gland lesions, 181–183 ectopic pancreas, 180–181 lipoma/hemangioma, 184–186 celiac disease, 151–154 congenital/developmental abnormalities, 124–129 malrotation, 124–126, 125f–126f paraduodenal hernia, 126–128, 127f–129f diverticula, 130–141 diverticulosis, 130–132 731 732 Index Small bowel (Cont.) Meckel’s diverticulum, 132–135 gastrointestional tuberculosis, 142–143, 142f–143f hemorrhage, 177–179, 178f–179f imaging techniques, 119–123, 119f, 121f–123f intussusception clinical features, 163 definition, 163 differential diagnosis, 164–165 imaging features, 163–164, 163f–165f management/clinical issues, 165 pathology, 163 pitfalls, 165 malignant tumors adenocarcinoma, 187–188, 187f–188f carcinoid tumor, 191–193, 192f–193f differential diagnosis, 184 gastrointestional stromal tumor, 193–195, 194f–195f lymphomas, 189–191, 189f–191f metastases, 195–197, 196f–197f malrotation anomalies, 124–126 mesentery, normal anatomy, 631–633, 632f metastases clinical features, 196 definition, 195 differential diagnosis, 181, 188, 193, 195, 196 imaging features, 196, 196f–197f management/clinical issues, 197 pathology, 196 nonsteroidal anti-inflammatory drug enteropathy, 149–150, 149f obstruction (SBO) closed-loop obstruction and strangulation, 159–162 differential diagnosis, 639 hernias, 671–672, 672f mechanical obstruction, 156–159, 156f–158f mesenteric fibromatosis, 664–665, 665f pancreatic transplant complication, 580–581 Roux-en-Y gastric bypass surgery, 104–105 opportunistic infection, 146–149, 147f–148f parasites, 144–145, 144f–145f scleroderma, 166–168 sclerosing mesenteritis, 667 trauma, 173–176 vascular disorders Henoch-Schönlein purpura, 172–173 mesenteric ischemia, 169–172 Small bowel series, techniques, 119–120, 119f Small-caliber esophagus, eosinophilic esophagitis, 31–32, 32f Soft tissue sarcoma, differential diagnosis abdominal wall desmoid tumor, 675 mesenteric fibromatosis, 666 sclerosing mesenteritis, 667 Solid pseudopapillary tumor, pancreas definition, 558 demographic/clinical features, 558 differential diagnosis, 552, 555, 557–558, 568, 571 imaging features, 558 management/clinical issues, 558–559 Somatostatin receptor scintigraphy, small bowel imaging, 123, 123f Spheroid sign, benign esophageal tumors, 34 Sphincter of Oddi, 522 contraction, 492 Spindle cell carcinoma, differential diagnosis esophageal cancer, 38 fibrovascular polyps, 35 Spleen anatomy, 585 angiosarcoma, 615–616, 615f–616f congenital anomalies and variants, 589–594 accessory spleen, 589–590, 590f–592f asplenia, 589–591 definition, 589 differential diagnosis, 591–594, 599–600 embryology, 589 polysplenia, 589–591, 594f splenic lobulation, 589–590 wandering spleen, 589–591, 593f cystic lesions abscesses and infections, 598–601, 599f–601f splenic cysts, 601–603, 602f–603f hamartoma, 607–611, 608f–610f hemangioma, 604–605, 605f–609f differential diagnosis, 605, 609–610, 616 hematoma, 626–627, 626f–627f imaging techniques, 585–586, 586f infarcts, 590, 590f–593f, 620–624, 623f infection, differential diagnosis, 613–614 intrapancreatic accessory spleen, 532–533, 533f littoral-cell angiomas, differential diagnosis, 616 lymphoma definition, 611 differential diagnosis, 613–614, 614–615, 618–619 nomenclature and classification, 614 metastases definition, 617 demographic/clinical features, 617 differential diagnosis, 600, 605, 610, 613, 616, 618–619, 703 imaging features, 617–618, 617f–618f pathology, 617 sarcoidosis, 702–703 trauma AAST splenic injury scale, 627t, 628 definition, 626 demographic/clinical features, 626 imaging findings, 626–627, 626f–627f management/clinical issues, 628 pathophysiology, 626 vascular disorders definition, 620 demographic/clinical features, 620 differential diagnosis, 624 imaging features, 621–624, 621f–624f management/clinical issues, 625 pathology/pathophysiology, 620–621 Splenic artery, aneurysms, 620–625, 621f differential diagnosis, 695 Splenic lobulation, 589–590 Splenic vein thrombosis, 620–624, 622f gastric varices, 94 Splenomegaly Index definition, 595 demographic/clinical features, 595 differential diagnosis, 596, 614–615, 614f–615f imaging features, 595–596 pathology, 595 type glycogen storage disease, 331–334 333f–334f Splenorenal ligament, normal anatomy, 633–634, 634f Spoiled gradient-echo (SGE) imaging, diverticulitis, 232 Sporadic adenomatosis, differential diagnosis, 334 Spot imaing, colon, 219–220, 220f Squamous cell carcinoma esophageal defined, 36 demographic/clinical features, 36 differential diagnosis, 38 imaging features, 37–38, 37f–38f management/clinical issues, 38–39 pathology, 36–37 pharynx, 8–9, 9f Steakhouse syndrome, Schatzki rings, 44 Steatohepatitis definition, 309 demographic/clinical features, 309 imaging techniques, 313 pathophysiology, 309–310 Steatorrhea, celiac disease, 153–154, 154f Steatosis definition, 309 demographic/clinical features, 309 differential diagnosis, 313–314 hepatocellular adenoma, 393 imaging features, 310–313, 310f–313f management/clinical issues, 314 pathophysiology, 309–310 Steatotic hepatocellular carcinoma, 401–402, 402f Stenosis, bile duct, cholecystectomy complications, 465 Stepladder sign feline esophagus, 29 peptic stricture, 28, 28f ringed esophagus, 32 STK11/LKB1 gene, Peutz-Jeghers syndrome, 683–684 Stomach anatomic segments, 51 benign tumors, 68–75 gastric polyps, 68–70 gastrointestinal stromal tumor, 70–73 lipomas, 73–75 imaging techniques, 51–54, 52f–54f inflammatory diseases of, 55–67 atrophic gastritis, 61–63 differential diagnosis, 86 emphysematous gastritis, 63–65 gastric ulcer, 57–60 Helicobactor pylori gastritis, 55–57 Ménétrier’s disease, 65–67 malignant tumors of, 76–87 gastric adenocarcinoma, 76–79, 77f–78f gastric lymphoma, 82–84, 82f–83f gastric metastases, 84–87, 86f gastric stromal tumors, 79–81, 80f–81f miscellaneous disorders, 94–102 gastric bezoar, 100–102 gastric diverticulum, 99–100 gastric outlet obstruction, 96–98 gastric varices, 94–96 mucosal types, 51 normal anatomy, 51 postoperative changes bariatric surgery, 103–110 Billroth/gastrojejunostomy, 113–115 fundoplication, 111–113 scleroderma, 166 Stomal narrowing, Roux-en-Y gastric bypass surgery, 104 Strongyloides stercoralis, small bowel infection, 147–149 Submucosal hematoma, 42 Submucosal infiltrating carcinoma, differential diagnosis, Helicobactor pylori gastritis, 56 Submucosal mesenchymal tumor, differential diagnosis, 181 Subscapular hematomas, differential diagnosis, 444 Superficial spreading carcinoma, differential diagnosis Candida esophagatis, 21 reflux esophagitis, 29 Superior mesenteric artery (SMA), pancreatic transplant surgery, 577–578, 578f Superior mesenteric vein anatomy, 521 occlusion, differential diagnosis, 160 Suppurative hidradenitis, differential diagnosis, 277 Supraglottic laryngeal structures, squamous cell carcinoma, 9, 9f Swallowing, normal pharyngeal function, 3–4 Systemic inflammatory response syndrome (SIRS), acute pancreatitis, 535 T1-weighted imaging abdominal wall desmoid tumors, 673–675, 673f–675f bile duct cholangiocarcinoma, 510 infectious cholangitis, 495, 495f magnetic resonance cholangiopancreatography, 482, 483f diverticulitis, 232 familial adenomatous polyposis, 680 hemoperitoneum, 646, 647f liver hepatic cysts, 371–372, 373f hepatic hemangiomas, 379–383, 380f–383f hypovascular metastases, 423, 425f iron overload, 319, 320f liver infarct, 342 steatosis, 311 transient hepatic enhancement difference, 438, 441f Wilson’s disase, 331–332, 332f–333f magnetic resonance colonography, 222, 225 magnetic resonance enterography, 122–123, 122f multicystic mesothelioma, 653–654, 654f pancreas autoimmune pancreatitis, 548, 548f–549f chronic pancreatitis, 545–546, 547f–548f cystic fibrosis, 530, 530f groove pancreatitis, 547–548, 547f intraductal papillary mucinous neoplasm, 551–553, 552f–553f 733 734 Index T1-weighted imaging (Cont.) mucinous cystic neoplasms (MCNs), 554–555 normal anatomy, 525 pancreatic ductal adenocarcinoma, 561–563, 561f–563f pancreatic endocrine tumors, 567f–567–568 serous microcystic pancreatic adenoma, 557, 557f rectal adenocarcnioma, 280–284, 281f–283f sclerosing mesenteritis, 667 sinusoidal obstruction syndrome, 357 spleen hamartoma, 609, 610f hemangioma, 604, 607f–609f metastases, 618, 618f normal anatomy, 586, 587f splenic artery aneurysms, 620–621, 620f–622f Von Hippel-Lindau (VHL) syndrome, 697–699, 698f T2-weighted imaging abdominal wall desmoid tumors, 673–675, 673f–675f anorectum, 265–267, 265f, 267f–268f bile duct cholangiocarcinoma, 510, 510f choledochal cysts, 487–488, 488f magnetic resonance cholangiopancreatography, 482, 483f variant anatomy, 485–486, 486f diverticulitis, 232 familial adenomatous polyposis, 680 fecal incontinence, 295–297, 296f gallbladder acute calculous cholecystitis, 454, 455f carcinoma, 476, 477f normal anatomy, 450–451, 452f hemoperitoneum, 646, 647f liver epithelioid hemangioendothelioma, 414, 415f hepatic cysts, 371–372, 373f hepatic hemangiomas, 379–383, 380f–383f hypovascular metastases, 423, 424f iron overload, 319, 320f liver infarct, 342 steatosis, 311 Wilson’s disase, 332, 333f magnetic resonance colonography, 222 magnetic resonance enterography, 122–123, 122f pancreas acute pancreatitis, 538–539, 538f annular pancreas, 527, 528f autoimmune pancreatitis, 548, 548f–549f cystic fibrosis, 530, 530f groove pancreatitis, 547–548, 547f intraductal papillary mucinous neoplasm, 551–553, 552f–553f mucinous cystic neoplasms (MCNs), 554–555, 555f normal anatomy, 525, 525f pancreatic ductal adenocarcinoma, 561–563, 561f–563f pancreatic endocrine tumors, 567f–567–568 serous microcystic pancreatic adenoma, 556–557, 556f–557f rectal adenocarcnioma, 280–284, 281f–283f sclerosing mesenteritis, 667 spleen hemangioma, 604, 607f–609f normal anatomy, 586, 587f splenomegaly, 595–596, 597f Von Hippel-Lindau (VHL) syndrome, 697–699, 698f Taenia solium/Taenia saginatum, small bowel infestation, 145 Tailgut cyst, 271, 272f, 273 “Tail” sign, abdominal wall desmoid tumors, 674 Target sign small bowel obstruction, 157, 157f ulcerative colitis imaging, 229, 229f Telangiectasias See hereditary hemorrhagic telangiectasia THAD See transient hepatic attenuation difference THED See transient hepatic enhancement difference THID See transient hepatic intensity difference Thoracic aorta, ectatic/aneursymal differential diagnosis, achalasia, 12 Thoracic esophageal diverticula, 18–20 See also pulsion diverticula esophageal varices and, 46–48, 47f Thrombosis bland portal vein thrombosis, 345–348 primary Budd-Chiari syndrome, 354–359 splenic vein thrombosis, 94 tumoral thrombosis, 348–353 Thyroglossal duct cysts, pharynx, 8, 9f Tight wrap edema, fundoplication complication, 112–113, 113f Tip appendicitis, differential diagnosis, 135 TIPS proceure, esophageal varices, 48 “Tissue paper” folds, atrophic gastritis imaging, 62, 62f TNM staging See tumor, node, metastasis (TNM) staging system Tongue, neuromuscular disorders, 7 Tonsillar pillars, normal anatomy, 3, 4f Toxic megacolon, differential diagnosis, 258 Traction diverticula, 18–20 defined, 18 imaging features, 19, 19f management/clinical issues, 20 Transabdominal ultrasonography (TA-US) multiple endocrine neoplasia syndrome, 695, 695f pancreas chronic pancreatitis, 543 intraductal papillary mucinous neoplasm, 551–553 normal anatomy, 522–523, 522f Transcatheter arterial chemoembolization, hepatocellular carcinoma, 408–412, 409f–411f Transient hepatic attenuation difference (THAD), definition, 436 Transient hepatic enhancement difference (THED) common variants and pitfalls, 439–441 definition, 436 demographic/clinical features, 436 differential diagnosis, 438–439 imaging features, 437–438, 437f–441f management/clinical issues, 441–442 pathogenesis and mechanism, 436–437 Transient hepatic intensity difference (THID), definition, 436 Transjugular portosystemic shunt, liver transplant evaluation, 362 Transpantation surgery liver, 361–367, 365f, 407–408 pancreas, 577–581, 577f–580f Index Transsphincteric fistula, 274–275, 275f, 277f Transverse mesocolon, normal anatomy, 631–633, 632f Trauma bile duct, 513–515, 513t, 514f compound/mixed sliding-paraesophageal hernia, 88–90 differential diagnosis Henoch-Schönlein purpura, 172 mesenteric ischemia, small bowel, 171 fecal incontinence, 296–297 hernia, 672 liver AAST grading system, 444, 444t definition, 443 delayed complications, 445 demographic/clinical features, 443 differential diagnosis, 444–445 imaging features, 443–444, 443f–445f liver infarct, 342–344 management/clinical issues, 445 mechanism, 443 small bowel, 173–176, 174f–176f spleen AAST splenic injury scale, 627t, 628 definition, 626 demographic/clinical features, 626 imaging findings, 626–627, 626f–627f management/clinical issues, 628 pathophysiology, 626 Trichobezoars, 101–102 Trichophytobezoar, 101–102 Tropical sprue, differential diagnosis, 152–154 Tuberculosis abdominal, 142–143, 142f–143f Crohn’s disease and, 140 differential diagnosis, 143 small bowel infections, 148 small bowel lymphoma, 190 infectious colitis, 241 liver involvement, 435 peritonitis, 649–650, 650f differential diagnosis, 656, 661 splenic abscesses and infections, 598–601, 599f–601f Tuberculous esophagitis, differential diagnosis, intramural dissection, 42 Tuberous sclerosis, pancreatic endocrine tumors, 565–569, 566f–568f Tumefactive sludge, differential diagnosis, 475 Tumor, Node, Metastasis (TNM) staging system anal carcinoma, 287, 287t–288t colorectal cancer, 254, 255t–256t pancreatic ductal adenocarcinoma, 562t small bowel adenocarcinoma, 188 Tumoral thrombosis, liver definition, 348 demographic/clinical features, 349 differential diagnosis, 512 imaging features, 349–350, 350f–353f liver transplant evaluation, 362 management/clinical issues, 351–353 pathophysiology, 349 Turcot’s syndrome, 681–682 Type glycogen storage disease definition, 330 demographic/clinical features, 330–331 differential diagnosis, 334 imaging features, 332–334, 333f–334f managaement/clinical issues, 334 pathophysiology, 331 Type A gastritis, 61–63 Type B gastritis, 61–63 Typhilitis See neutropenic enterocolitis Typhlitis See neutropenic colitis Ulcerative carcinomas, gastric adenocarcinoma, 77 Ulcerative colitis backwash ileitis, 140, 141f definition, 227 demographic/clinical features, 227 differential diagnosis, 226, 229–230 diverticulitis, 234 infectious colitis, 241 pseudomembranous colitis, 237 imaging features, 227–229, 228f–229f management/clinical issues, 230 pathology, 227 Ulcerative lymphomas, gastric lymphomas, 83, 83f Ulcer mound, gastric ulcer, 59 Ulcers “collar-button” ulcers, ulcerative colitis, 228, 228f Crohn’s disease, 139, 139f gastric ulcers, 57–60 giant ulcers, esophageal, 31, 38 malignant ulcer, 59 Ultrasound imaging abdominal wall desmoid tumors, 673–675, 673f–675f hernias, 669–670, 670f–672f appendix appendiceal adenocarcinoma, 214–215, 214f–215f appendiceal mucinous cystadenoma, 211–212, 212f–213f appendicitis, 205, 205f ascites, 641–642, 641f bile duct cholangiocarcinoma, 509, 509f choledochal cysts, 488, 488f choledocholithiasis, 490–491, 491f–492f IgG4-related sclerosing cholangitis, 501–502, 502f infectious cholangitis, 495 biliary cystadenoma/cystadenocarcinoma, 374–375, 375f colon, 221 colonic obstruction, 257, 258f Crohn’s disease, 225 diverticulitis, 231–232, 232f fecal incontinence, 295–297, 296f gallbladder acute acalculous cholecystitis, 456, 457f acute calculous cholecystitis, 453–454, 453f adenomyomatosis, 471, 472f carcinoma, 475–476, 476f gallstone ileus, 469–470, 469f gangrenous cholecystitis, 459–460, 459f–460f normal anatomy, 449–451, 450f 735 736 Index Ultrasound imaging (Cont.) polyps, 474–475, 474f porcelain gallbladder, 462f xanthogranulomatous cholecystitis, 462–463f hemoperitoneum, 645–646, 646f–647f intraperitoneal abscess, 643–644, 644f ischemic colitis, 244–245, 244f–245f liver, 301–303, 303f Budd-Chiari syndrome, 355–356, 356f cirrhosis, 324–326, 325f–326f echinococcal cyst, 434, 434f focal nodular hyperplasia, 385, 385f hepatic artery aneurysm, 336–337 hepatic artery thrombosis, post-transplant, 363–365, 365f hepatic cysts, 371–372, 371f hepatic hemangiomas, 379–383, 380f hepatic lymphoma, 427, 427f hepatocellular adenoma, 391 hepatocellular carcinoma benign and premalignant nodules, 397–398, 398f diagnosis, 402–403, 402f hereditary hemorrhagic telangiectasia, 340 hypervascular metastases, 419–422 hypovascular metastases, 423, 424f iron overload, 318, 318f pyogenic abscess, 431, 431f steatosis, 310–311, 310f tumoral thrombosis, 349–353, 350f Von Meyenberg complexes, 377f, 378 Wilson’s disase, 331 lymphangioma, 651–652, 651f–652f malignant mesothelioma, 655–656, 655f mesenteric fibromatosis, 664, 664f multicystic mesothelioma, 653, 653f neutropenic colitis, 239, 239f pancreas acinar cell carcinoma, 570, 571f acute pancreatitis, 537–538 chronic pancreatitis, 543 mucinous cystic neoplasms (MCNs), 554 normal anatomy, 522–523, 522f pancreatic endocrine tumors, 565–566, 566f serous microcystic pancreatic adenoma, 556 transplant surgery, 577–579, 578f–580f peritoneal carcinomatosis, 660–661, 660f pneumoperitoneum, 637, 637f pseudomembranous colitis, 237 pseudomyxoma peritonei, 662 sinusoidal obstruction syndrome, 356–357, 359f spleen accessory spleen, 590, 590f angiosarcoma, 615, 615f–616f hamartoma, 609, 609f hemangioma, 604, 605 lymphoma, 612–613, 613f normal anatomy, 585–586, 586f splenic artery aneurysms, 621–622 splenic cysts, 602–603, 603f splenic vein thrombosis, 620–622, 622f traumatic injury, 626–627, 626f–627f wandering spleen, 590–591, 593f splenomegaly, 595–596 type glycogen storage disease, 331–334 333f–334f ulcerative colitis, 229 Zollinger-Ellison syndrome, 691–692 Umbilical hernia, 670–671 Unclosed closed-loop small bowel obstruction, 161, 161f Undifferentiated embryonal cell carcinoma, 375 Uneven lipomatosis, pancreas, 532, 532f Uphill esophageal varices, 46–48, 47f Valleculae, normal anatomy, 3, 4f Varices esophageal, differential diagnosis, esophageal cancer, 38 gastric, 66, 94–96 small bowel, differential diagnosis, 186 Varicoid carcinoma, differential diagnosis, esophageal varices, 47–48 Varioliform erosions, differential diagnosis, gastric metastases, 86 Vascular disorders See also arterial disorders liver transplantation, 363–365, 365f pancreas, transplant complications, 579, 579f small bowel Henoch-Schönlein purpura, 172–173 mesenteric ischemia, 169–172 trauma, 173–176 vascular tumor, differential diagnosis, 186 spleen definition, 620 demographic/clinical features, 620 differential diagnosis, 624 imaging features, 621–624, 621f–624f management/clinical issues, 625 pathology/pathophysiology, 620–621 Vena cava obstruction, downhill esophageal varices, 46–48, 47f Veno-occlusive disorders liver definition, 354 demographic/clinical features, 354 differential diagnosis, 357 hepatocellular carcinoma, 401–402 hereditary hemorrhagic telangiectasia, differential diagnosis, 341 imaging features, 355–356, 355f–359f management/clinical issues, 357, 359 pathophysiology, 355 primary Budd-Chiari syndrome, 354–359 sinusoidal obstruction, 354–359 transient hepatic enhancement difference, 437 transplant evaluation, 362 splenic vein thrombosis, 620–622, 622f gastric varices, 94 Ventral hernia, 670–671 VHL See Von Hippel-Lindau (VHL) syndrome Vigorous achalasia, 11–12, 12f differential diagnosis, diffuse esophageal spasm, 14 VIPoma, differential diagnosis, celiac disease, 154 Viral esophagitis defined, 22 demographic/clinical features, 23 differential diagnosis, 23–24 Index reflux esophagitis, 29 imaging features, 23–24, 23f–24f management/clinical issues, 25 pathology, 23 Vitamin B12 deficiency, atrophic gastritis, 61 Volvulus cecal, 261, 261f colonic, 260–262 gastric, 90–92 midgut, malrotation, 124–126, 125f–126f sigmoid, 260–261, 260f small bowel, differential diagnosis, 160, 161f Von Gierke disease See type glycogen storage disease Von Hippel-Lindau (VHL) syndrome common variants, 699 definition, 697 demographic/clinical features, 697 differential diagnosis, 699 genetics, 697 imaging features, 697–699, 698f management/clinical issues, 699 pancreas, 531, 531f pancreatic endocrine tumors, 565–569, 566f–568f Von Meyenberg complexes definition, 376 demographic/clinical features, 376 differential diagnosis, 378 imaging features, 377f, 378 management/clinical issues, 378 pathology, 377 Waldeyer’s ring, non-Hodgkin’s lymphoma, 9–10 Wandering spleen, 589–591, 593f “Water-lily” sign, echinococcal cyst, 434, 434f “Watershed” ischemic colitis, 244–245, 244f Weber-Christian disease, differential diagnosis, 667 Whipple procedure pancreatic ductal adenocarcinoma, 562 postoperative management, 575–576, 575f–577f Whipple’s disease, differential diagnosis, 148 sclerosing mesenteritis, 667 Wilson’s disease definition, 330 demographic/clinical features, 330 differential diagnosis, 322 neuropsychiatric symptoms, 330 pathophysiology, 331 Xanthogranulomatous cholecystitis, 461–463, 463f differential diagnosis, 477 Yersinia enteritis, differential diagnosis, 143 Zenkers diverticulum, 16–18 defined, 16 demographic and clinical features, 16 differential diagnosis, 17 imaging features, 16, 17f management/clinical issues, 17–18 pathology, 16 ZES See Zollinger-Ellison syndrome Zollinger-Ellison syndrome (ZES) common variant, 693 definition, 691 demographic/clinical features, 691 differential diagnosis, 692–693 celiac disease, 154 gastric varices, 95 Ménétrier’s disease, 66 imaging features, 691–692, 692f management/clinical issues, 693 pathology, 691 737 ... Radiology 20 12; 2 62( 2): 520 – 529 Grazioli L, Federle MP, Brancatelli G, Ichikawa T, Olivetti L, Blachar A Hepatic adenomas: imaging and pathologic findings RadioGraphics 20 01 ;21 :877–8 92; discussion, 8 92 874... Imaging of benign hepatic masses Semin Liver Dis 20 01 ;21 :23 7 24 9 Jang HJ, Yu H, Kim TK Imaging of focal liver lesions Semin Roentgenol 20 09;44 :26 6 28 2 Vilgrain V, Boulos L, Vullierme MP, Denys A,... Radiology 20 01; 22 1:731–739 Hussain SM, Terkivatan T, Zondervan PE, et al Focal nodular hyperplasia: findings at state-of-the-art MR imaging, US, CT, and pathologic analysis Radiographics 20 04 ;24 :3–17;