ExpertDDx: Abdomen and Pelvis

Dr. Atif Zaheer has a specialty focus on CT, MR, and US of the abdomen and pelvis. He is Professor of Radiology, Oncology and Medicine at The Johns Hopkins University School of Medicine in Baltimore, Maryland. Dr. Siva Raman is a board-certified radiologist who gained his subspecialty expertise in thoracoabdominal imaging during a fellowship at Stanford University, and intern residency at UC Davis Medical Center. He attended Johns Hopkins University Medical School. Dr. Raman is a radiologist at Bay Imaging Consultants in Walnut Creek, California, with a subspecialty focus on thoracoabdominal imaging Dr. Bryan Foster is a body imaging radiologist with a subspecialty focus on oncologic, hepatobiliary, pancreatic, prostate, and small bowel imaging. Dr. Foster is the Professor of Radiology at Oregon Health & Science University in Portland, Oregon, and performs complex image-guided biopsies; he also performs CEUS imaging and US elastography. Dr. Foster is skilled in all facets of imaging including radiography, fluoroscopy, ultrasound, CT, and MRI. His interests include oncologic, hepatobiliary, pancreatic, prostate, and small bowel imaging. Dr. Foster has recently started performing contrast-enhanced ultrasound imaging (as the only site in Oregon) and US elastography. He is one of two radiologists that perform MRI-guided prostate biopsies (also only site in Oregon). Recently he was selected as an Honored Educator for the Radiological Society of North America. Dr. Ghaneh Fananapazir is a radiologist with specialization in abdominal radiology. He is Professor of Radiology at the University of California - Davis, in Sacramento, California. Fananapazir's clinical focus includes nonvascular interventional procedures, advanced US, CT and MR techniques, vascular imaging, and abdominal organ transplantation (kidney, liver, pancreas). In addition to his clinical duties, Dr. Fananapazir is passionate about medical education and research, particularly relating to kidney transplantation, and has authored textbooks and peer-reviewed research in highly impactful medical journals.

• SECTION 1: PERITONEUM AND MESENTERYGENERIC IMAGING PATTERNS4 Mesenteric or Omental Mass (Solid)Siva P. Raman, MD10 Mesenteric or Omental Mass (Cystic)14 Fat-Containing Lesion, Peritoneal Cavity18 Mesenteric Lymphadenopathy22 Abdominal Calcifications28 Pneumoperitoneum32 Hemoperitoneum36 Misty (Infiltrated) MesenteryMODALITY-SPECIFIC IMAGING FINDINGS COMPUTED TOMOGRAPHY42 High-Attenuation (Hyperdense) AscitesSECTION 2: ABDOMINAL WALLANATOMICALLY BASED DIFFERENTIALS48 Abdominal Wall Mass52 Mass in Iliopsoas Compartment54 Groin Mass58 Elevated or Deformed Hemidiaphragm60 Defect in Abdominal Wall (Hernia)SECTION 3: ESOPHAGUS66 Intraluminal Mass, EsophagusAtif Zaheer, MD and Michael P. Federle, MD, FACR68 Extrinsic Mass, Esophagus72 Lesion at Pharyngoesophageal Junction74 Esophageal Ulceration76 Mucosal Nodularity, Esophagus78 Esophageal Strictures80 Dilated Esophagus82 Esophageal Outpouchings (Diverticula)84 Esophageal DysmotilityCLINICALLY BASED DIFFERENTIALS86 OdynophagiaSECTION 4: STOMACH90 Gastric Mass Lesions96 Intramural Mass, Stomach98 Target or Bull's-Eye Lesions, Stomach100 Gastric Ulceration (Without Mass)102 Intrathoracic Stomach104 Thickened Gastric Folds110 Gastric Dilation or Outlet Obstruction114 Linitis Plastica, Limited Distensibility118 Epigastric Pain124 Left Upper Quadrant MassSECTION 5: DUODENUM130 Duodenal Mass136 Dilated Duodenum138 Thickened Duodenal FoldsSECTION 6: SMALL INTESTINE142 Multiple Masses or Filling Defects, Small Bowel144 Cluster of Dilated Small Bowel146 Aneurysmal Dilation of Small Bowel Lumen148 Stenosis, Terminal Ileum150 Segmental or Diffuse Small Bowel Wall Thickening156 Pneumatosis of Small Intestine or Colon160 Occult GI Bleeding164 Small Bowel ObstructionSECTION 7: COLON172 Solitary Colonic Filling Defect174 Multiple Colonic Filling Defects176 Mass or Inflammation of Ileocecal Area182 Colonic Ileus or Dilation186 Toxic Megacolon188 Rectal or Colonic Fistula194 Segmental Colonic Narrowing198 Colonic Thumbprinting200 Colonic Wall Thickening206 Smooth Ahaustral Colon208 Acute Right Lower Quadrant Pain214 Acute Left Lower Quadrant PainSECTION 8: SPLEEN222 Splenomegaly226 Multiple Splenic Calcifications228 Solid Splenic Mass or Masses230 Cystic Splenic Mass232 Diffuse Increased Attenuation, SpleenSECTION 9: LIVER236 Liver Mass With Central or Eccentric Scar240 Focal Liver Lesion With Hemorrhage244 Liver "Mass" With Capsular Retraction246 Fat-Containing Liver Mass248 Cystic Hepatic Mass252 Focal Hypervascular Liver Lesion258 Liver Mass With Mosaic EnhancementAtif Zaheer, MD262 Mosaic or Patchy Hepatogram266 Hepatic Calcifications270 Liver Lesion Containing Gas274 Portal Venous Gas276 Widened Hepatic Fissures278 Dysmorphic Liver With Abnormal Bile Ducts282 Focal Hyperperfusion Abnormality (THAD or THID)MAGNETIC RESONANCE IMAGING288 Multiple Hypodense Liver Lesions294 Multiple Hypointense Liver Lesions (T2WI)298 Hyperintense Liver Lesions (T1WI)304 Liver Lesion With Capsule or Halo on MR308 Focal Hyperdense Hepatic Mass on Nonenhanced CT312 Periportal Lucency or Edema318 Widespread Low Attenuation Within LiverULTRASOUND322 Focal Hepatic Echogenic Lesion ± AcousticShadowingAtif Zaheer, MD, Gregory E. Antonio, MD, DRANZCR,FHKCR, and Eric K. H. Liu, PhD, RDMS328 Hyperechoic Liver, Diffuse330 HepatomegalyHee Sun Park, MD, PhD and Aya Kamaya, MD, FSRU, FSAR334 Diffuse Liver Disease336 Cystic Liver Lesion340 Hypoechoic Liver Mass344 Echogenic Liver Mass348 Target Lesions in Liver350 Multiple Hepatic Masses354 Hepatic Mass With Central Scar356 Periportal Lesion360 Irregular Hepatic SurfaceAya Kamaya, MD, FSRU, FSAR362 Portal Vein AbnormalitySECTION 10: GALLBLADDER366 Distended Gallbladder368 Gas in Bile Ducts or Gallbladder372 Focal Gallbladder Wall Thickening374 Diffuse Gallbladder Wall ThickeningJade Wong-You-Cheong, MBChB, MRCP, FRCR, FSRU,FSAR378 High-Attenuation (Hyperdense) Bile in Gallbladder380 Hyperechoic Gallbladder Wall382 Echogenic Material in Gallbladder384 Dilated Gallbladder388 Intrahepatic and Extrahepatic Duct DilatationL. Nayeli Morimoto, MD and Aya Kamaya, MD, FSRU,390 Right Upper Quadrant PainSECTION 11: BILIARY TRACT398 Dilated Common Bile Duct404 Asymmetric Dilation of Intrahepatic Bile Ducts408 Biliary Strictures, Multiple412 Hypointense Lesion in Biliary Tree (MRCP)SECTION 12: PANCREAS416 Hypovascular Pancreatic Mass422 Hypervascular Pancreatic Mass426 Cystic Pancreatic Mass432 Atrophy or Fatty Replacement of Pancreas434 Dilated Pancreatic Duct438 Infiltration of Peripancreatic Fat Planes444 Pancreatic Calcifications448 Cystic Pancreatic LesionFauzia Vandermeer, MD452 Solid Pancreatic Lesion456 Pancreatic Duct DilatationSECTION 13: RETROPERITONEUM460 Retroperitoneal Mass, CysticMatthew T. Heller, MD, FSAR466 Retroperitoneal Mass, Soft Tissue Density472 Retroperitoneal Mass, Fat Containing474 Retroperitoneal HemorrhageSECTION 14: ADRENAL478 Adrenal MassMitchell Tublin, MDSECTION 15: KIDNEY486 Solid Renal Mass490 Cystic Renal Mass494 Bilateral Renal CystsAlessandro Furlan, MD498 Infiltrative Renal LesionsGhaneh Fananapazir, MD502 Perirenal and Subcapsular Mass Lesions506 Renal Cortical Nephrocalcinosis508 Medullary Nephrocalcinosis510 Perirenal HemorrhageAmir A. Borhani, MD514 Fat-Containing Renal Mass518 Calcified Small Lesion in Kidney522 Renal Sinus Lesion528 Gas in or Around Kidney530 Delayed or Persistent Nephrogram534 Wedge-Shaped or Striated Nephrogram538 Enlarged Kidney542 Small Kidney546 Hypoechoic Kidney550 Hyperechoic Kidney554 Renal Pseudotumor556 Dilated Renal PelvisNarendra Shet, MD560 Hyperechoic Renal MassSECTION 16: COLLECTING SYSTEM568 Dilated Renal Calices572 Radiolucent Filling Defect, Renal PelvisSECTION 17: URETER576 Ureteral Filling Defect or Stricture580 Cystic Dilation of Distal UreterSECTION 18: BLADDER584 Filling Defect in Urinary Bladder590 Urinary Bladder Outpouching592 Gas Within Urinary Bladder594 Abnormal Bladder WallAshish P. Wasnik, MD, FSARSECTION 19: URETHRA600 Urethral StrictureSECTION 20: SCROTUM604 Intratesticular Mass608 Testicular Cystic Lesions610 Extratesticular Cystic Mass612 Extratesticular Solid Mass614 Diffuse Testicular EnlargementShweta Bhatt, MD616 Decreased Testicular Size618 Testicular CalcificationsSECTION 21: PROSTATE AND SEMINAL VESICLES622 Focal Lesion in Prostate626 Enlarged ProstateKatherine To'o, MDSECTION 22: FEMALE PELVIS630 Pelvic FluidAkram M. Shaaban, MBBCh634 Female Lower Genital Cysts640 Extra-Ovarian Adnexal MassMaryam Rezvani, MD646 Acute Pelvic Pain in Non-Pregnant WomenSECTION 23: UTERUS654 Enlarged Uterus658 Thickened Endometrium664 Abnormal Uterine BleedingSECTION 24: OVARY672 Multilocular Ovarian Cysts678 Unilocular Ovarian Cysts684 Solid Ovarian Masses688 Calcified Ovarian Masses692 Ovarian Lesions With Low T2 Signal Intensity