High-intensity focused ultrasound (HIFU) for the treatment of uterine fibroids: does HIFU significantly increase the risk of pelvic adhesions?

Figures & data

Figure 1. CONSORT flow diagram of the enrollment and data analysis of patients with uterine fibroids underwent surgical treatment.

Figure 2. Pelvic adhesions detected under laparoscopical surgery.

Table 1. Baseline characteristics of the patients in the two groups.

Variables	HIFU group (n = 96)	Control group (n = 1713)	p Value
Age ($\overline{x}$ ± s)	39.15 ± 5.46	42.18 ± 5.67	.080
Menstrual volume ($\overline{x}$ ± s, ml)	80.55 ± 4.96	81.12 ± 3.48	.103
Menstrual period ($\overline{x}$ ± s, d)	7.89 ± 1.08	8.65 ± 1.14	.097
Size of uterine fibroids ($\overline{x}$ ± s, cm)	4.82 ± 0.56	5.57 ± 0.82	.634
Number of Abortions [n(P2,5P75)]	2 (1.00,2.88)	2 (1.00, 3.12)	.112
Deliveries [n(P2,5P75)]	1 (1.00, 2.05)	1 (1.00, 2.30)	.090

Table 2. Comparison of the incidence of pelvic adhesions in the two groups.

	HIFU group (n = 96)	Control group (n = 1713)	Chi-square value	p value
Without pelvic adhesion [n (％)]	54 (56.25)	1094 (63.86)	2.273	.132
With adhesion [n (％)]	42 (43.75)	619 (36.14)

Table 3. Location of adhesions in the two groups.

Variables	HIFU group (n/%)	Control group (n/%)	Chi-square value	p Value
Uterus
Adhesion	19 (19.8)	318 (18.6)	0.090	.764
No adhesion	77 (80.2)	1395 (81.4)
Fallopian tubes
Adhesion	4 (4.2)	119 (6.9)	0.713	.398
No adhesion	92 (95.8)	1594 (93.1)
Ovaries
Adhesion	3 (3.1)	27 (1.6)	0.555	.456
No adhesion	93 (96.9)	1686 (98.4)
Cul-de-sac
Adhesion	5 (5.2)	41 (2.4)	2.907	.088
No adhesion	91 (94.8)	1672 (97.6)
Bladder
Adhesion	4 (4.2)	45 (2.6)	0.338	.561
No adhesion	92 (95.8)	1668 (97.4)
Bowel
Adhesion	7 (7.3)	69 (4.0)	2.406	.121
No adhesion	89 (92.8)	1644 (96.0)

Table 4. Comparison of the severity of pelvic adhesions between the two groups [n (％)].

	HIFU group (n = 42)	Control group (n = 619)	Chi-square value	p Value
Mild	25 (59.52)	288 (46.53)	2.719	.257
Moderate	10 (23.81)	184 (29.73)
Severe	7 (16.67)	147 (23.75)

Table 5. The related factor analysis of pelvic adhesions in the HIFU group [n(％)].

Variables	Without adhesions (n = 54)	With adhesions (n = 42)	Chi-square value	p Value
Age (year)
＜35	11 (20.37)	6 (14.29)	1.357	.507
35–40	15 (27.78)	16 (38.10)
>40	28 (51.85)	20 (47.62)
Number of abortions
＜2	7 (12.96)	14 (33.33)	14.429	.001
2–5	24 (44.44)	24 (57.14)
>5	23 (42.59)	4 (9.52)
Parturition times
≤2	36 (66.67)	38 (90.48)	6.294	.012
>2	18 (33.33)	4 (9.52)
Dysmenorrheal history
With	19 (35.19)	23 (54.76)	3.679	.055
Without	35 (64.81)	19 (45.24)
Lesion volume
<3.5	19 (35.19)	10 (23.81)	10.844	.004
3.5–4	27 (50.00)	13 (30.95)
>4	8 (14.81)	19 (45.24)

Table 6. The multi-factor correlation analysis of pelvic adhesions in the HIFU group.

Variables	Regression coefficient (B)	Standard error (S.E.)	Chi-square value (Wald)	p Value	Odds ratio (Exp (B))
Number of abortions	0.349	0.463	0.536	.448	1.408
Parturition times	0.500	0.517	0.666	.525	1.696
Lesion volume	0.047	0.714	0.004	.925	1.059

Table 7. The HIFU treatment results between the patients with and without adhesions in HIFU group.

Variables	With adhesions	Without adhesions	p Value
Total energy used for fibroid ablation (J)	330,666 (60,000–529,200]	230,878 (79,450–793,450)	0.034
Treatment time (min)	73 (20–119)	57 (27–140)	.021
Sonication time (S)	876 (240–1428)	684 (324–1680)	.048
NPV ratio	82.3% (35.2–97.8%)	89.7% (41.5–98.6%)	.005
EEF (J/mm^3)	5.98 [0.4–28.9] ()	2.25 ([1.5–27.6])	.000

EEF = Ƞpt/v(J/mm³) Ƞ = 0.7.

NPV ratio: Non-perfused volume ratio.

Table 8. The related factor analysis of pelvic adhesions in the control group [n(％)].

Variables	Without adhesions (n = 1094)	With adhesions (n = 619)	Chi-square value	p Value
Age(year)
＜35	210 (19.20)	37 (5.98)	104.131	.000
35-40	260 (23.77)	273 (44.10)
>40	624 (57.04)	309 (49.92)
Number of abortions
＜2	328 (29.98)	283 (45.72)	54.752	.000
2–5	657 (60.05)	314 (50.73)
>5	109 (9.96)	22 (3.55)
Parturition times
≤2	864 (78.98)	482 (77.87)	0.289	.591
>2	230 (21.02)	137 (22.13)
Dysmenorrheal history
With	416 (38.03)	225 (36.35)	0.475	.491
Without	678 (61.97)	394 (3.65)
Lesion volume
<3.5	251 (22.94)	72 (11.63)	61.243	.000
3.5–4	481 (43.97)	388 (62.68)
>4	362 (33.09)	159 (25.69)

Table 9. The multi-factor correlation analysis of pelvic adhesions in the control group.

Variables	Regression coefficient (B)	Standard error (S.E.)	Chi-square value (Wald)	p Value	Odds ratio (Exp(B))
Age	0.151	0.365	0.174	.656	1.165
Number of abortions	0.335	0.510	0.646	.538	1.603
Lesion volume	−0.488	0.319	2.422	.108	0.596
Dysmenorrheal history	0.172	0.518	0.119	.729	1.219