Efficacy of Three Different Injection Techniques for the Endoscopic Treatment of Vesicoureteral Reflux (VUR) in Children: A Review of 10 Years of Experience

Figures & data

Figure 1 Schematic illustration of the HIT technique (a), STING technique (b), and “combined HIT-STING” technique (c).

Table 1 Baseline Characteristics of the Cohort of Patients Included in the Study

	Combined HIT-STING Technique	STING Technique	HIT Technique	p-value
Patients (n; %)	74 (53%)	44 (31%)	22 (16%)
Ureters (n; %)	119 (52%)	73 (32.0%)	36 (16%)
Patient age at surgery (years)	3.0 (2.0–7.0)	3.0 (2.0–5.0)	3.5 (2.0–6.0)	0.653
Gender:
– Female (n; %)	26 (35%)	27 (61%)	11 (50.0%)	0.020
– Male (n; %)	48 (65%)	17 (39%)	11 (50.0%)
Laterality:
– Monolateral	31 (42%)	22 (50%)	12 (55%)	0.491
– Bilateral	43 (58%)	22 (50%)	10 (45%)
VUR grade
– I–II (n, %)	39 (33%)	27 (37%)	8 (22%)	0.574
– III (n, %)	51 (43%)	29 (40%)	19 (53%)
– IV (n, %)	23 (19%)	16 (22%)	7 (19%)
– V (n, %)	6 (5%)	1 (1%)	2 (6%)
Secondary VUR or VUR associated with other anomalies of the urinary tract (n, %)	22 (29%)	17 (39%)	10 (45%)	0.330
Bulking agent
– Dextranomer/hyaluronic acid (Dx/HA) (n, %)	81 (68%)	67 (92%)	33 (92%)	< 0.0001
– Polyacrylate polyalcohol copolymer (PPC) (n, %)	38 (32%)	6 (8%)	3 (8%)
Volume of dextranomer/hyaluronic acid (Dx/HA) injected (mL)	0.9 (0.6–1.1)	1.3 (1.0–1.6)	0.5 (0.4–0.8)	< 0.0001
Volume of polyacrylate polyalcohol copolymer (PPC) injected (mL)	0.7 (0.6–0.8)	1.8 (1.6–2.0)	0.2 (0.2–0.4)	0.0064

Table 2 Surgical Outcomes Comparing the 3 Different Endoscopic Techniques

	Combined HIT-STING Technique (n=119 Ureters; 52%)	STING Technique (n=73 Ureters; 32%)	HIT Technique (n=36 Ureters; 15.8%)	p-value
Resolution rate after a single endoscopic injection of bulking agent (n; %)	110 (92%)	62 (85%)	31 (86%)	0.225
Overall resolution rate of the endoscopic treatment (n; %)	116 (98%)	69 (95%)	34 (94%)	0.469
Resolution in case of secondary VUR or VUR associated with other anomalies of the urinary tract (n; %)	17/22 (77%)	12/17 (71%)	9/10 (90%)	0.506
Grade I–II VUR, resolution following:
– 1st injection (n; %)	38/39 (97%)	24/27 (89%)	8/8 (100%)	0.248
– 2nd injection (n; %)	1/39 (3%)	3/27 (11%)	0/8 (0%)
Grade III VUR, resolution following:
– 1st injection (n; %)	47/51 (92%)	24/29 (83%)	16/19 (84%)	0.645
– 2nd injection (n; %)	2/51 (4%)	2/29 (7%)	1/19 (5%)
– Ureteroneocystostomy (n; %)	2/51 (4%)	3/29 (10%)	2/19 (11%)
Grade IV VUR, resolution following:
– 1st injection (n; %)	20/23 (87%)	13/16 (81%)	5/7 (71%)	0.700
– 2nd injection (n; %)	2/23 (9%)	2/16 (13%)	2/7 (29%)
– Ureteroneocystostomy (n; %)	1/23 (4%)	1/16 (6%)	0/7 (0%)
Grade V VUR, resolution following:
– 1st injection (n; %)	5/6 (83%)	1/1 (100%)	2/2 (100%)	1.000
– 2nd injection (n; %)	1/6 (17%)	0/1 (0%)	0/2 (0%)

Figure 2 Baseline characteristics of the cohort of patients included in the study (upper rows) and surgical outcomes comparing the 3 different endoscopic techniques (lower rows).

Notes: *p-value: <0.05; **p-value: <0.01; ***p-value: <0.001; ****p-value: <0.0001.