Urinary bladder wall abnormalities (BWA) detected at transabdominal ultrasound (US): A prospective study on diagnostic agreement between two operators with different experience

Purpose: To evaluate diagnostic agreement for BWA detected at US between two operators with different experience

Methods: 87 consecutive patients (M/F=73/14; mean age 68yrs) underwent cystoscopy (CYS) owing to hematuria (61 pts), recent incidental US finding of BWA (13 pts), follow-up of urothelial cancers (32 pts). US was carried out by two operators with different experience in abdominopelvic US(operator A: 20 years; operator B: 5 years of experience) in the same session (1–2 days before CYS). Operators were blind to clinical and/or US findings and used top-level machines equipped with tissue harmonic and compound imaging. A preliminary consensus on both technical modality of performing US exam and pitfalls in bladder US diagnostics was obtained. Agreement for presence, number, size and location of BWA (e.g. polypoid vegetations and/or asymmetric bladder wall thickening) was assessed by means of the k statistics. CYS was the diagnostic method of reference.

Results: The two operators showed similar sensitivity (both 90.9%), specificity (A=85.7%; B=80.9%) and overall accuracy (A=89.6% vs. B=88.5%) in the diagnosis of BWA detected at CYS. Agreement was excellent for the identification of BWA (k=1), good for size (k=0.78), location (k=0.62) and number (k=0.70) of BWA

Conclusion: US represents a valuable diagnostic tool for identifying BWA detected at CYS independently from operators experience provided that a high standard of US examination is achieved through both preliminary consensus on technical and diagnostic issues and use of top-level US machines.