Retrograde-viewing device improves adenoma detection rate in colonoscopies for surveillance and diagnostic workup

Table 1 Additional adenoma detection rates for second exams by indication for procedure

Indication	Group A (SC, then TEC)			Group B (TEC, then SC)			Net additional detection with TEC (%)
	SC 1st	TEC 2nd	Additional in 2nd exam (%)	TEC 1st	SC 2nd	Additional in 2nd exam (%)
All indications	107	49	45.8	115	26	22.6	23.2
Screening	54	19	35.2	52	16	30.8	4.4
Surveillance	37	20	54.1	49	9	18.4	35.7
Diagnostic	16	10	62.5	14	1	7.1	55.4
Surveillance + diagnostic	53	30	56.6	63	10	15.9	40.7

TEC: Third Eye colonoscopy; SC: Standard colonoscopy.

Table 2 Adenoma miss rates¹ by indication for procedure

Indication	Group A standard colonoscopy first	Group B Third Eye colonoscopy first	Relative risk2 (95% CI)	P
All Indications3	49/173 = 0.283	26/176 = 0.148	1.92 (1.25-2.94)	0.029
Screening	19/91 = 0.209	16/85 = 0.188	1.11 (0.62-2.04)	0.815
Surveillance	20/36 = 0.556	9/51 = 0.176	3.15 (1.63-6.10)	0.014
Diagnostic	10/44 = 0.227	1/38 = 0.026	8.64 (1.16-64.41)	0.039
Surveillance + diagnostic	30/80 = 0.375	10/89 = 0.112	3.34 (1.74-6.39)	0.003

¹Expressed in adenomas per patient;

²Relative risk of missing an adenoma during first exams with standard colonoscopy vs first exams with Third Eye colonoscopy, 95% CI calculated using 2 × 2 frequency table;

³In 4 subjects (2 in group A and 2 in group B), no indication was specified.

Table 3 Per-polyp miss rates for standard colonoscopy and Third Eye colonoscopy by size of adenoma and indication for procedure

	Adenomas missed with standard colonoscopy during 1st exams in group A (%)			Adenomas missed with Third Eye colonoscopy during 1st exams in group B (%)
	< 10 mm	≥10 mm	All sizes	< 10 mm	≥10 mm	All sizes
All indications	33.8	11.8	31.4	20.8	0	18.4
Screening	27.7	12.5	26.0	28.1	0	23.5
Surveillance	37.7	0	35.1	16.7	0	15.5
Diagnostic	42.9	20.0	38.5	7.1	0	6.7
Surveillance + diagnostic	39.2	11.1	36.1	14.7	0	13.7

Table 4 Mean procedural times (min)

Indication	All exams with SC		All exams with TEC
	Withdrawal time	Total procedure time	Withdrawal time	Total procedure time
All indications	7.6	17.0	9.5	20.9
Screening	7.5	16.0	9.6	19.4
Surveillance	7.9	16.4	9.5	21.8
Diagnostic	7.5	19.8	9.6	23.2
Surveillance + diagnostic	7.7	18.1	9.5	22.5

Total procedure time: Total time from initial insertion of the colonoscope to withdrawal through the anal verge; Withdrawal time: Time from cecum to anal verge, excluding pauses for polypectomy or extensive suctioning; TEC: Third Eye colonoscopy; SC: Standard colonoscopy.