title: Ultrasonography for the diagnosis of acute appendicitis.
abstract: Acute appendicitis is usually encountered clinically as acute abdomen. Typical cases are easy to diagnose, but it can sometimes be very difficult to make a diagnosis in atypical cases. We retrospectively studied patients who underwent ultrasonography for right-sided lower abdominal pain suggesting acute appendicitis, and assessed the accuracy of ultrasonic diagnosis. The subjects were 202 patients (100 males and 102 females) aged 6-89 years (mean: 33.3 years). From the ultrasonic findings, appendicitis was classified as follows: 1) catarrhal: a clear layer structure of the appendiceal wall and mucosal edema; 2) phlegmonous: an ill-defined layer structure of the appendiceal wall, moderate enlargement of the apendix, and maximum transverse dimension of > or = 10 mm; and 3) gangrenous: unidentifiable layer structure of the appendiceal wall and marked enlargement to form a mass. The appendix was visualized in 142 of the 202 patients (70.3 %). When the appendix was detected, the sensitivity, specificity and accuracy of ultrasound for making a diagnosis of appendicitis were 97.6%, 82.0 %, 91.5 %, respectively. With regard to assessment of the severity of inflammation, ultrasonic and histologic findings were concordant in 61.2 % of the patients. However, ultrasound was shown to possibly underestimate the extent of inflammation. On the other hand, 11 of the 60 patients with an undetectable appendix (18.3 %) were clinically diagnosed as having appendicitis. The pathologic diagnosis was catarrhal appendicitis in 3 patients and phlegmonous appendicitis in 8 patients. In patients with an undetectable appendix, the possibility of catarrhal or phlegmonous appendicitis should be kept in mind.
authors.affiliation: Department of Surgery, Tokai University Oiso Hospital, Isehara, Kanagawa, Japan. shin.ji-h@dc4.so-net.ne.jp
authors.forename: Shinji
authors.initials: S
authors.lastname: Himeno
authors.forename: Seiei
authors.initials: S
authors.lastname: Yasuda
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Oida
authors.forename: Sayuri
authors.initials: S
authors.lastname: Mukoyama
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nishi
authors.forename: Masaya
authors.initials: M
authors.lastname: Mukai
authors.forename: Hisao
authors.initials: H
authors.lastname: Nakasaki
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Makuuchi
mesh_terms: D000006:Abdomen, Acute / Q000000981:diagnostic imaging; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001064:Appendicitis / Q000000981:diagnostic imaging*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014463:Ultrasonography