56 Imaging in Gastrointestinal Disorders: Diagnoses nodularity, andstricture. mucosal ulcerationſt, pseudomembranes st, demonstrates esophagus inthesamepatient Endoscopic imageofthedistal esophagitis. (Right) important signofreflux esophagus, acommonand foreshortening ofthe pulled tautasaresultofthe herniated stomach﬇is dilation oftheesophagus.The junction withupstream stricture ſtjustabovetheGE esophagram showsatight (Left) Pronefilmfroman indicate mucosalulceration. collections ofbarium﬈ junction, andpersistent gastroesophageal (GE) stricture ispresentatthe its longitudinalmuscles.A presumably duetospasmof appears shortened, diaphragm. Theesophagus ſt extendingabovethe hiatal herniawithgastricfolds esophagram showsasmall (Right) Spotfilmfroman stricture ofdistalesophagus. of themucosa,andatapered of theesophagus,ulceration ſt linkedwithforeshortening type 1(sliding)hiatalhernia (Left) Graphicshowsasmall • • • • TOP DIFFERENTIALDIAGNOSES • • • • • IMAGING • TERMINOLOGY Eosinophilic esophagitis Infectious esophagitis Drug-induced esophagitis Scleroderma tapered narrowingofdistalesophagus Peptic stricture(1-to4-cmlength):Concentric,smooth, ○ Hiatal herniain>95%ofpatientswithstricture elevations Inflammatory esophagogastricpolyps:Smooth,ovoid Foreshortening ofesophagus:Duetomusclespasm Irregular ulceratedmucosaofdistalesophagus gastroesophageal (GE)reflux Inflammation ofesophagealmucosadueto Probably isresult,notcause,ofreflux Reflux Esophagitis KEY FACTS • • • CLINICAL ISSUES • • PATHOLOGY • ○ monitoring techniques Confirmatory testing:Manometric/ambulatorypH- ○ Symptoms: Heartburn,regurgitation,angina-likepain ○ therapy reflux; ~30%failtorespondstandard-dosemedical 15-20% ofAmericanscommonlyhaveheartburndueto Hydrochloric acidandpepsin:Synergisticeffect increased reflux Lower esophagealsphincter:Decreasedtoneleadsto Caustic esophagitis Endoscopy, biopsy Dysphagia, odynophagia with obesityepidemic Prevalence ofGErefluxdiseasehasincreasedsharply 276

Colon the appendixonultrasound. make itdifficulttovisualize common variantthatmay its retrocecallocation,a the inflamedappendixſtand same patienthelpstoidentify Coronal reformattedCTinthe walled appendixſt.(Right) and nodesstaroundathick- inflammation ofthefatplanes exam. AxialCTshows pain withanequivocalUS acute rightlowerquadrant (Left) Thisyoungwomanhad appendicitis. process anddiagnosticfor indicative ofaninflammatory inflammation offatſt, hyperechoic periappendiceal diameter withadjacent appendix ﬇,10mmin distended, thick-walled ultrasound demonstratesa (Right) Longitudinal cecum andterminalileumst. of theadjacentwalls and inflammatorythickening walled, inflamedappendixſt including thedistended,thick- of acuteappendicitis, of thecharacteristicfeatures (Left) Graphicillustratessome • • • IMAGING • TERMINOLOGY ○ ○ CT: Abnormalmuralenhancementofdistendedappendix ○ ○ ○ ○ mm) US: Distended,thick-walled,noncompressibleappendix(≥7 ○ US is1st-lineimagingtoolinchildrenandyoungwomen and superimposedinfection Acute appendicealinflammationduetoluminalobstruction Necrotic wallmayshownoenhancement Inflamed mucosamayshowhyperenhancement Increased echogenicityofinflamedperiappendicealfat inflammation Increased flowwithinwallofappendix,indicating Shadowing, echogenicappendicolith appendix Sonographic McBurneysignwithfocalpainover sensitivity andspecificity(>90%) Multiplanar, contrast-enhancedCThashighest Appendicitis KEY FACTS • CLINICAL ISSUES • • • • • • • TOP DIFFERENTIALDIAGNOSES • women, andelderlyadults Clinical diagnosisisfrequentlyincorrectinchildren,young Cecal carcinoma Appendiceal tumor Cecal diverticulitis Gynecologic causes Crohn's disease Ileocolitis Mesenteric adenitisandenteritis children whenUSisnondiagnostic MR isgoodalternativetoCTinpregnantpatientsand ○ ○ ○ ± periappendicealabscessorphlegmon Appendicolith maybepresent(15-40%) Periappendiceal fatstranding Colon 277 (Right) In the same patient, a STIR image (top) and a DWI (bottom) show the edematous, thickened wall of the appendix ſt that also shows restricted diffusion. Acute appendicitis was confirmed at surgery. identify the inflamed appendix ſt lying medial to the ascending colon ﬇. (Right) Coronal CT in the same patient shows the appendix arising from the tip of the cecum ﬇. The inflamed portion of the appendix ſt along with the inflamed fat and nodes st are at some distance from the cecal tip, accounting for the atypical site of maximum tenderness on exam. (Left) This woman presented in her 2nd trimester of pregnancy with acute abdominal pain and fever. Following a nondiagnostic US exam, she had an MR study. On these T2 images, the gravid uterus and fetus ﬇ are evident along with a dilated, thick-walled appendix ſt arising from the cecal tip. This 61-year-old man (Left) This 61-year-old signs and had atypical right abdominal symptoms of pain. Axial CT shows the in an inflamed appendix ſt unusually medial position flexure relative to the hepatic of the colon ﬇. (Right) in the Another axial CT section same patient shows typical signs of appendicitis, including wall the thickened, enhancing the ſt and inflammation of local fat and nodes st. (Left) Coronal reformatted CT in the same patient helps to Appendicitis