Endoscopic ultrasound has been proposed as a less invasive means of diagnosing choledocholithiasis.
It may eliminate the need for Endoscopic Retrograde Cholangiopancreatography (ERCP) and its associated risks.
The literature pertaining to endoscopic ultrasound for the diagnosis of choledocholithiasis reports widely varying sensitivities and specificities.
|Endoscopic ultrasound had a high overall pooled sensitivity of 0.94|
Dr Frances Tse and colleagues from Canada estimated the diagnostic accuracy of endoscopic ultrasound in suspected choledocholithiasis.
The team used MEDLINE and EMBASE databases to identify prospective cohort studies in which the results of endoscopic ultrasound were compared with the results of an acceptable criterion standard.
The team reported that 2 independent reviewers extracted standardized data and assessed trial quality.
A random effects model was used to estimate the sensitivity, specificity, likelihood, and diagnostic odds ratio, and a summary receiver operating characteristic curve was constructed.
All predefined potential sources of heterogeneity were explored by subgroup analysis and meta-regression.
The team found a total of 2,673 patients with suspected choledocholithiasis were reported in 27 studies that satisfied the inclusion criteria.
The researchers noted that endoscopic ultrasound had a high overall pooled sensitivity of 0.94, a specificity of 0.95, and an area under the curve of 0.98.
The research team found 3 variables that appeared to yield a higher diagnostic odds ratio.
These variables included a higher disease prevalence, an adequate time interval between index test and criterion standards, and the presence of verification bias.
The team observed that misclassification of patients by imperfect criterion standards could potentially underestimate the performance of an endoscopic ultrasound.
Dr Tse's team concluded, "An endoscopic ultrasound is a noninvasive test, with excellent overall sensitivity and specificity for diagnosing choledocholithiasis."
"An endoscopic ultrasound should, therefore, be used to select patients for a therapeutic ERCP to minimize the risk of complications associated with unnecessary diagnostic ERCP."