Imaging pancreatobiliary ductal system with optical coherence tomography: A review

Table 1 Imaging methods for diagnosis of bile duct strictures n (%)

Techniques	SEN (%)	SPEC	PPV	NPV	Accuracy
BC/FNA[2,11,23]	30 (30-60)	95 (90-100)	100 (90-100)	28 (28-50)	48 (30-50)
Forceps biopsy[2,11,23]	43 (40-70)	90 (90-100)	95 (90-100)	31 (30-50)	48 (30-70)
BC + FNA + biopsy[2,11,23]	62 (60-75)	90 (90-100)	96 (90-100)	39 (35-60)	55 (45-75)
ERCP/MRCP[9,17,32,50-52]	70 (67-90)	75 (70-80)	80 (68-90)	88 (70-95)	70 (50-80)
ERCP-BC/BX[9,11,33,38]	43 (36-60)	80 (75-100)	95 (94-100)	90 (56-100)	70 (60-75)
EUS[17,32,33,47,53]	80 (70-100)	80 (75-100)	80 (76-100)	80 (54-90)	80 (78-90)
EUS-FNA[9,23]	85 (80-100)	95 (90-100)	95 (95-100)	80 (60-90)	85 (80-90)
IDUS[32,38]	90 (85-100)	85 (80-100)	85 (80-100)	90 (80-100)	90 (83-90)
IDUS + ERCP/biopsy[32,33,38,54]	91 (90-100)	93 (90-100)	94 (84-100)	90 (84-95)	92 (90-100)
OCT[1,2]	79 (75-90)	69 (65-90 )	75 (70-90)	73 (70-90)	74 (70-85)
OCT-BC/BX[2]	84 (80-90)	69 (70-90)	76 (70-90 )	78 (70-100)	77 (70-90)

True positive (TP) and true negative (TN) represent the accurate diagnosis of biliary and non-biliary strictures respectively; False positive (FP) reflects the incorrect diagnosis of non-malignancy, whereas, false negative (FN) reflects incorrect diagnosis of the benign strictures; Sensitivity, specificity, positive predictive values and negative predictive values were calculated as Ref. [54]. BC: Brush cytology; BX: Forceps biopsy; FNA: Fine-needle aspiration; ERCP: Endoscopic retrograde cholangiopancheatography; MRCP: Magnetic resonance cholangiopancreatography; EUS-FNA: Endoscopic ultrasound-guided FNA biopsy; IDUS: Intraductal ultrasonography; OCT: Optical coherence tomography; SEN: TP (TP + FN); SPEC: TN/(TN + FP); PPV: TP/(TP + FP); NPV: TN/(TN + FN).