Intraoperative ultrasound as an educational guide for laparoscopic biliary surgery

Table 6 Diagnostic accuracy of IOUS (%)

	Sensitivity		Specificity		PPV		NPV		Overall accuracy
	Pre-op	IOUS	Pre-op	IOUS	Pre-op	IOUS	Pre-op	IOUS	Pre-op	IOUS
Anatomical variation	25	100	100	100	100	100	96	100	96	100
Cholecystolithiasis	99	100	100	100	100	100	87	100	99	100
Bile duct stone	76	76	100	99	100	93	95	95	96	95
Polyps	77	82	98	98	77	75	98	99	97	97
Others	50	81	93	95	70	82	86	94	83	92

PPV: Positive predictive value; NPV: Negative predictive value; Pre-op: Preoperative image studies; Anatomical variation: Anatomical variation of the extrahepatic bile duct. Preoperative image studies included extracorporeal ultrasonography (100%), computed tomography (73%), endoscopic retrograde cholangiopancratography (51%), drip infusion cholangiography (42%), magnetic resonance cholangiopancreatography (20%), and/or percutaneous transhepatic cholangiography (5%).