CEUS in the differential diagnosis between biliary sludge, benign lesions and malignant lesions

J Ultrasound. 2018 Jun;21(2):119-126. doi: 10.1007/s40477-018-0286-5. Epub 2018 Feb 23.

Abstract

Purpose: Conventional grayscale ultrasound (US) is accurate in the diagnosis of gallbladder disease (GD), but in some cases, it is not decisive. Contrast-enhanced ultrasound (CEUS) improves the diagnostic accuracy of US. The primary objective of this study is to assess the reliability of CEUS in the diagnosis of sludge; the secondary objective is to assess the ability of CEUS to diagnose cancer.

Methods: We retrospectively reviewed the US of 4137 patients positive for GD. In 43/4137 (1.04%), the use of could not discriminate between sludge and neoplasms. Then, we evaluated CEUS in only 39 of these patients, and in 4/43 (9%) cases it was not performable. After CEUS, the absence of enhancement was considered diagnostic for sludge, while contrast washout within 60 s diagnosed malignant lesions.

Results: Among the 39 patients, 16 had biliary sludge and 23 had lesions of the gallbladder wall; 9 of these were carcinomas and 14 were benign tumors. The absence of enhancement was present in 16/16 patients with sludge and in 0/23 patients with lesions of the gallbladder (sensitivity and specificity 100%). Washout was within 60 s in 9/9 gallbladder carcinomas and 2/14 benign lesions (sensitivity 100%; specificity 85%).

Conclusions: US is confirmed to be accurate in the diagnosis of GD. In doubtful cases, CEUS is very accurate in biliary sludge diagnosis. An intralesional washout at 60 s is a pattern of malignancy that can orient towards a correct diagnosis, but it is limited by the presence of false positive results, especially for smaller lesions.

Scopo: L’ecografia convenzionale in scala dei grigi (US) è accurata nella diagnosi delle malattie colecistiche (GD) ma in alcuni casi non è decisiva. L’ecografia con mezzo di contrasto (CEUS), migliora l’affidabilità diagnostica dell’US. Obiettivo primario di questo studio è quello di determinare l’affidabilità della CEUS nella diagnosi di fango biliare; obiettivo secondario definire l’affidabilità della CEUS nella diagnosi di carcinoma della colecisti.

Metodi: Abbiamo analizzato retrospettivamente 4137 ecografie di pazienti positive per GD. In 43/4137 (1.04%) l’ecografia non era capace di discriminare tra fango e neoplasie. La CEUS era valutata in soli 39 pazienti, in 4/43 (9%) dei casi non era eseguibile. L’assenza di enhancement alla CEUS era considerato diagnostico per sludge, mentre un washout del contrasto entro 60 secondi era diagnostico per malattie maligne. L’assenza di enhancement era presente in 16/16 pazienti con fango e in 0/23 pazienti con lesioni colecistiche (sensibilità e specificità 100%). Il wash-out era presente a 60 sec in 9/9 tumori colecistiti e in 2/14 lesioni benigne (sensibilità 100%, specificità 85%).

Conclusioni: L’ecografia si conferma accurata nella diagnosi delle GD. Nei casi dubbi la CEUS è veramente accurata nella diagnosi di sludge. Un wash out intralesionale a 60 secondi è un pattern di malignità che può orientare verso una corretta diagnosi, ma è limitato dalla presenza di risultati falsi positivi, specialmente nelle lesioni più piccole.

Keywords: Benign disease; CEUS; Gallbladder; Malignant disease; Sludge; Ultrasound.

MeSH terms

  • Adult
  • Aged
  • Bile / diagnostic imaging*
  • Carcinoma / diagnostic imaging
  • Contrast Media*
  • Diagnosis, Differential
  • Female
  • Gallbladder / diagnostic imaging*
  • Gallbladder Diseases / diagnostic imaging*
  • Humans
  • Male
  • Middle Aged
  • Reproducibility of Results
  • Retrospective Studies
  • Sensitivity and Specificity
  • Ultrasonography* / methods

Substances

  • Contrast Media