Ultrasound-guided high intensity focused ultrasound for the treatment of gynaecological diseases: A review of safety and efficacy

High-intensity focused ultrasound (HIFU) for the treatment of female urinary incontinence: A retrospective analysis

This study aims to demonstrate the effectiveness of high-intensity focused ultrasound, a noninvasive treatment, for managing urinary incontinence (UI) in women. This is a single-center, retrospective study involving 28 women. Patients, aged between 32 and 65, were included. Patients with insulin-dependent diabetes, neurological disease, active urinary tract infection, undiagnosed vaginal bleeding, who had incontinence surgery, and receiving estrogen therapy were excluded from the study. Incontinence severity was evaluated with the International Incontinence Consultation Questionnaire Short Form (ICIQ-SF). Patients were evaluated before treatment and 6 months after treatment using the ICIQ-SF and the Pelvic Organ Prolapse/Urinary Incontinence Sexual Function Assessment short form. In the analysis of numerical variables independent or paired t test or linear mixed effects models were used. Least square means were used in post hoc comparisons. Mean age of the patients was 45.50 ± 7.59 years. There were 18 (64%) stress urinary incontinence (SUI) and 10 (36%) mixed urinary incontinence (MUI). Six months after treatment, mean ICIQ-SF and Pelvic Organ Prolapse/Urinary Incontinence Short Form Questionnaire scores showed a significant positive change. After the procedure, UI completely disappeared in 43% of the patients. The rate of severe UI decreased from 39% to 8%, and very severe UI decreased from 8% to 0%. Incontinence severity was significantly different in the MUI and SUI groups before and after the procedure. After the procedure, UI completely disappeared in 67% of the patients in the SUI group, while it remained at a mild level in 33%. The decrease in ICIQ-SF score in the SUI group was significantly higher than that in the MUI group. There were no severe adverse events, in 4 patients there was mild vaginal discharge which resolved in 1 week. This study showed that high-intensity focused ultrasound treatment, can be effective and safe even in a single session. Selection and recall biases are potential biases in retrospective studies. Lacking a control group is another limitation. Although advances in technology are very important for medical treatments, their effectiveness and safety need to be proven. Future research in this area with a larger sample size and a prospective design will offer further evidence supporting effectiveness of this treatment model.

An Updated Review of Thermal Ablation Technology for Uterine Fibroids and Adenomyosis: Focusing on Protecting Fertility

There is a growing trend towards minimally invasive or noninvasive alternatives for gynecological disorders due to their rapid alleviation of symptom, expedited recovery, and minimal risks of postoperative complications. Thermal ablation technology has been commonly advocated as a minimally invasive therapeutic methods in recent years, including microwave ablation, radiofrequency ablation, and high-intensity focused ultrasound. The increasing application scenarios require updated and systematic research, and more evidence to promote their appropriate use. The objective of this review is to summarize the latest views of ablation from a prospective of fertility protection, endeavor to clarify the clinical value of thermal ablation technology in protecting fertility by assessing parameters such as ablation rates, alleviation of disease symptoms, re-intervention rates and post-treatment pregnancy rates. We review the clinical studies of ablation for uterine fibroids and adenomyosis treatment in the past 10 years, summarize the limitation and the prospects of its development in the treatment process, so as to provide clinicians with advice on the best practice. In the management of uterine fibroids and adenomyosis, thermal ablation technology offers improved fertility preservation and minimizes normal tissue injury compared to traditional surgical approaches for patients pursuing reproductive goals. In the future, thermal ablation technology will play a significantly enhanced role in preserving fertility for individuals requiring treatment for uterine fibroids and adenomyosis, guided by indications. But further research is still needed in the form of more extensive randomized prospective trials to provide stronger evidence supporting this perspective.

Therapeutic effects of focused ultrasound on vulvar squamous intraepithelial lesions in rat

OBJECTIVE

In this study, we established a Sprague-Dawley rat model of vulvar squamous intraepithelial lesions and investigated the impact of focused ultrasound on the expression of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and mutant type p53 (mtp53) in the vulvar skin of rats with low-grade squamous intraepithelial lesions (LSIL).

MATERIALS AND METHODS

The vulvar skin of 60 rats was treated with dimethylbenzanthracene (DMBA) and mechanical irritation three times a week for 14 weeks. Rats with LSIL were randomly allocated into the experimental group or the control group. The experimental group was treated with focused ultrasound, while the control group received sham treatment.

RESULTS

After 14 weeks treatment of DMBA combined with mechanical irritation, LSIL were observed in 44 (73.33%) rats, and high-grade squamous intraepithelial lesions (HSIL) were observed in 14 (23.33%) rats. 90.91% (20/22) of rats showed normal pathology and 9.09% (2/22) of rats exhibited LSIL in the experimental group at four weeks after focused ultrasound treatment. 22.73% (5/22) of rats exhibited LSIL, 77.27% (17/22) of rats progressed to HSIL in the control group. Compared with the control-group rats, the levels of HIF-1α, VEGF and mtp53 were significantly decreased in experimental-group rats (p < 0.05).

CONCLUSIONS

These results indicate that DMBA combined with mechanical irritation can induce vulvar squamous intraepithelial lesion in SD rats. Focused ultrasound can treat LSIL safely and effectively, prevent the progression of vulvar lesions, and improve the microenvironment of vulvar tissues by decreasing the localized expression of HIF-1α, VEGF, and mtp53 in rats.

A systematic review of the side effects of high-intensity focused ultrasound ablation of uterine fibroids

Background

A new intervention called high-intensity focused ultrasound (HIFU) targets fibroids with high-intensity ultrasound pulses using ultrasound probes. This noninvasive method, which can be carried out with either magnetic resonance imaging or ultrasound guidance, results in immediate coagulated necrosis within a clearly defined area a few millimeters in diameter.

Methods

This systematic review evaluated the safety of HIFU in the treatment of uterine fibroids regardless of site or size. We specifically aimed to determine the incidence of side effects that can occur during and after HIFU. We searched the PubMed, Scopus, ScienceDirect, and Mendeley archive using only the terms HIFU and fibroid. After identifying 1077 studies of different types from 2014 to March 2024, 300 studies were screened and 60 included.

Results

According to Society of Interventional Radiology guidelines, class A adverse events (AEs) showed no significant results, and individuals with these AEs required no treatment and had no long-term consequences. Similarly, there were no class B significant results. However, 3943 of 10,204 patients (38%) complained of lower abdominal pain after the procedure, a class B AE, which resolved by analgesics. Further, 153 of 24,700 patients (0.6%) had skin burns, blisters, or nodules, and these issues resolved with conservative treatment. Additionally, 74 of 23,741 patients (0.3%) had hematuria; 882 of 5970 patients (14.7%) had abnormal vaginal discharge; 414 of 23,449 (1.7%) had vaginal bleeding; and 267 of 7598 (3.5%) had leg paresthesia. Major AEs (class C and D) were almost nonexistent, and the incidence of death in our study was zero.

Conclusion

HIFU ablation of uterine fibroids is generally safe, causing mostly mild side effects and very few severe complications. The relative safety of HIFU compared to other minimally invasive techniques, such as uterine artery embolization, still needs further evaluation.

Comparing the effect of FUAS and myomectomy on the elasticity of myometrium around targeted uterine fibroid

BACKGROUND

Focused ultrasound ablation surgery (FUAS) has been widely employed to treat patients with uterine fibroid (UF). This study aimed to estimate myometrial stiffness changes in patients who received FUAS for UFs or myomectomy (ME) and compare the recovery of surrounding myometrium between FUAS and ME groups. Our results may provide more evidence for guiding the proper conception timing in patients with UF.

METHODS

This study enrolled 173 patients from May 2022 to August 2023. Shear wave elastography (SWE) was used to dynamically monitor myometrial elasticity changes in patients before and after surgery. Moreover, our study monitored and analyzed the stiffness changes in the targeted fibroid after FUAS, as well as in the myometrium around after FUAS or ME.

RESULTS

The stiffness of the myometrium around the resected fibroid was significantly higher than at the preoperative level until 6 months. Conversely, the stiffness of the surrounding myometrium was only temporarily increased 1 day after FUAS. The comparison between FUAS and ME groups regarding the stiffness of the surrounding myometrium showed that nonsignificant differences were detected between the two groups before the treatment. The stiffness of the surrounding myometrium in the ME group was statistically significantly higher than that of the FUAS group 1 day as well as 1, 3, and 6 months after the treatment, respectively.

CONCLUSION

The FUAS had less impact on the surrounding myometrium than the ME, which may be more conducive to the recovery of myometrial elasticity in patients with UF.

Differential Analysis of Pregnancy Outcomes After Treatment of HIFU and LEEP in Patients with Cervical High-Grade Squamous Intraepithelial Lesions

Purpose

To verify whether there is lower incidence of adverse pregnancy outcomes after high-intensity focused ultrasound (HIFU) treatment than loop electrosurgical excision procedure (LEEP) in young women of childbearing age.

Patients and Methods

This retrospective cohort study enrolled 46 patients treated with HIFU and 46 patients treated with LEEP. To compare the differences between the two groups, Fisher's exact test or the Kruskal-Wallis (K-W/H) test was used in the univariate analysis, while the logistic regression method was applied for further verification.

Results

Basic characteristics showed no differences between the two groups (P > 0.05) except for parity (P < 0.001). Preterm birth rates were 6.52% and 0.00% in patients with cervical high-grade squamous intraepithelial lesions (HSIL) treated with LEEP and HIFU, respectively. The incidence rates of premature rupture of membranes (PROM) were respectively 15.22% and 21.74% in the two groups. There was no significant difference in pregnancy outcomes between the two groups (P > 0.05).

Conclusion

This study is the first to compare the pregnancy outcomes of patients with cervical HSIL who treated with LEEP and HIFU procedures. Both HIFU treatment and LEEP are available options for patients of reproductive age with cervical HSIL. Therefore, it is necessary to conduct prospective single-center or multicenter randomized controlled studies.

Complications and adverse events of high-intensity focused ultrasound in its application to gynecological field - a systematic review and meta-analysis

OBJECTIVE

To analyze and summarize the types, incidence rates and relevant influencing factors of adverse events (AEs) after high-intensity focused ultrasound ablation of gynecological diseases and provide reference and basis for handling such events in clinical practice.

METHOD

We searched PubMed, Cochrane Library, Web of Science and Embase databases to retrieve all literature since its establishment until February 2024. We evaluated the quality of included literature and publication bias and conducted a meta-analysis of single group rates for various AEs using Stata 17.0.

RESULTS

This systematic review finally included 41 articles. We summarized 34 kinds of AEs in 7 aspects and conducted a single group rate meta-analysis and sub-group analysis of 16 kinds of AEs. Among the common AEs of High-Intensity Focused Ultrasound (HIFU), the incidence of lower abdominal pain/pelvic pain is 36.1% (95% CI: 24.3%∼48.8%), vaginal bleeding is 20.6% (95% CI: 13.9%∼28.0%), vaginal discharge is 14.0% (95% CI: 9.6%∼19.1%), myoma discharge is 24% (95% CI: 14.6%∼34.8%), buttock pain is 10.8% (95% CI: 6.0%∼16.5%) and sacral pain is 10% (95% CI: 8.8%∼11.2%). Serious complications include uterine rupture, necrotic tissue obstruction requiring surgical intervention, third degree skin burns and persistent lower limb pain or movement disorders.

CONCLUSION

The common AEs after HIFU surgery are mostly mild and controllable, and the incidence of serious complications is extremely low. By reasonable prevention and active intervention, these events can be further reduced, making it a safe and effective treatment method. It is a good choice for patients who crave noninvasive treatment or have other surgical contraindications.

Laparoscopic treatment of abdominal wall endometriosis: A case series

Objective

This report summarizes the characteristics of a series of 8 recent (2020-2022) patients with abdominal wall endometriosis (AWE) who underwent laparoscopic surgery. The feasibility and advantages of laparoscopy in the treatment of AWE are set out.

Methods

The clinical data of the 8 AWE patients were retrospectively analysed. Basic clinical characteristics, operation details and postoperative details were collected and analysed.

Results

Laparoscopic treatment was successful in all 8 cases. The mean operation time was 212.13 ± 48.16 min, the mean estimated blood loss was 25.00 ± 11.18 ml, and the mean postoperative hospital stay was 5.25 ± 1.39 days. 7 of the patients were found to have concomitant pelvic endometriosis, and 1 patient was found to have concealed inguinal hernias during surgery. Concomitant laparoscopic surgery for pelvic lesions was performed, including electrocautery or lesion resection of the pelvic endometriosis lesions in 7 patients, uterine fibroidectomy in 2 patients, high ligation of the hernia sac in 1 patient and endometrial biopsy under hysteroscopy in 1 patient. Endometrial-like tissue was confirmed by postoperative pathological examination of resected AWE lesions in all patients. There were no intraoperative or postoperative complications. The mean follow-up time was 18.75 ± 3.96 months, and no recurrence of AWE was found.

Conclusion

Laparoscopic surgery is a safe, effective and feasible treatment option for AWE patients and has the advantages of simultaneous diagnosis and treatment of other pelvic lesions.

Evaluation of Dual-Frequency Switching HIFU for Optimizing Superficial Ablation

OBJECTIVE

Dual-frequency high-intensity focused ultrasound (HIFU) thermal ablation is an exceptionally promising technique for treating tumors due to its precision and effectiveness. However, there are still a few studies on improving the accuracy and efficiency of HIFU in superficial ablation applications. This study proposes a method utilizing dual frequency switching ultrasound (DFSU) to enhance the efficiency and precision of superficial treatments.

METHODS

A dual-frequency HIFU transducer operating at 4.5 MHz and 13.7 MHz was designed, and a dual-frequency impedance matching network was designed to optimize electro-acoustic conversion efficiency. Phantom and ex vivo tests were conducted to measure and compare thermal lesion areas and temperature rises caused by single-frequency ultrasound (SFU) and DFSU.

RESULTS

In both phantom and ex vivo tests, the utilization of DFSU resulted in larger lesion areas compared to SFU. Moreover, DFSU provided improved control and versatility, enabling precise and efficient ablation.

CONCLUSION

DFSU exhibits the ability to generate larger ablation areas in superficial tissue compared to SFU, and DFSU allows flexible control over the ablation area and temperature rise rate. The acoustic power deposition of HIFU can be optimized to achieve precise ablation.

Changes in liver and kidney function, red blood cell count and hemoglobin levels 1 day after ultrasound-guided percutaneous microwave ablation for uterine fibroids

OBJECTIVE

To investigate the changes in liver and kidney function, red blood cell (RBC) count and hemoglobin (HGB) levels in patients undergoing ultrasound-guided percutaneous microwave ablation (UPMWA) for uterine fibroids on postoperative day 1.

METHODS

The changes in liver and kidney function, RBC count and HGB levels in 181 patients who underwent selective UPMWA in the Second Affiliated Hospital of Shantou University Medical College, China, between August 2017 and January 2023 were retrospectively analyzed.

RESULTS

All patients underwent UPMWA for uterine fibroids; 179 patients had multiple uterine fibroids and 2 patients had single uterine fibroids. The maximum fibroid diameter ranged from 18 to 140 mm, with an average of 68.3 mm. Ultrasound imaging was used to confirm that the blood flow signal within the mass had disappeared in all patients, indicating that the ablation was effective. Within 24 h, compared with before UPMWA, levels of total bilirubin, direct bilirubin, indirect bilirubin and aspartate aminotransferase had significantly increased (p < 0.01), whereas levels of total protein, albumin, globulin, alanine aminotransferase, creatinine and urea had significantly decreased (p < 0.01). Acute kidney injury (AKI) occurred in 1 of the 181 patients. The RBC count and HGB levels decreased significantly after UPMWA (p < 0.01).

CONCLUSION

Ultrasound-guided percutaneous microwave ablation for uterine fibroids can impose a higher detoxification load on the liver and cause thermal damage to and the destruction of RBCs within local circulation, potentially leading to AKI. Protein levels significantly decreased after UPMWA. Therefore, perioperative organ function protection measures and treatment should be actively integrated into clinical practice to improve prognosis and enhance recovery.

Efficacy and safety of high-intensity focused ultrasound combined with suction curettage for the treatment of caesarean scar pregnancy: a systematic review and single-arm meta-analysis

PURPOSE

Caesarean scar pregnancy (CSP) presents a significant clinical challenge owing to the associated risks of uterine scar rupture, severe haemorrhage and adverse maternal outcomes. This study aimed to assess the safety and efficacy of combining high-intensity focused ultrasound (HIFU) with suction curettage for treating CSP.

METHODS

We conducted a comprehensive search in four databases, namely PubMed, Web of Science, Embase and Cochrane Library, to identify published studies evaluating the use of HIFU combined with suction curettage to treat CSP. Intraoperative blood loss, treatment success rate, and reproductive results were the primary outcomes assessed.

RESULTS

A total of 18 studies involving 1251 patients with CSP, all of whom received preoperative HIFU therapy were included. The average hospital stay was 6.22 days, the intraoperative blood loss was 26.29 ml and the incidence of adverse events was 15.60%, including abdominal or lower limb pain, fever, vaginal bleeding, haematuria and vomiting. Furthermore, post-treatment follow-up showed that serum β-human chorionic gonadotropin levels were rapidly normalized (average of 25.48 days) and menstruation returned (average of 33.03 days). The treatment had a remarkable success rate of 97.60% and a subsequent pregnancy rate of 68.70%.

CONCLUSION

While the combination of HIFU and suction-curettage may induce common adverse effects such as lower abdominal or limb pain, these reactions typically do not necessitate therapeutic intervention. Additionally, the size of the gestational sac is a determinant of the procedure's success. In conclusion, HIFU combined with suction curettage demonstrates promising clinical efficacy, safety and favourable reproductive outcomes in managing CSP.

Prediction of non-perfusion volume ratio for uterine fibroids treated with ultrasound-guided high-intensity focused ultrasound based on MRI radiomics combined with clinical parameters

BACKGROUND

Prediction of non-perfusion volume ratio (NPVR) is critical in selecting patients with uterine fibroids who will potentially benefit from ultrasound-guided high-intensity focused ultrasound (HIFU) treatment, as it reduces the risk of treatment failure. The purpose of this study is to construct an optimal model for predicting NPVR based on T2-weighted magnetic resonance imaging (T2MRI) radiomics features combined with clinical parameters by machine learning.

MATERIALS AND METHODS

This retrospective study was conducted among 223 patients diagnosed with uterine fibroids from two centers. The patients from one center were allocated to a training cohort (n = 122) and an internal test cohort (n = 46), and the data from the other center (n = 55) was used as an external test cohort. The least absolute shrinkage and selection operator (LASSO) algorithm was employed for feature selection in the training cohort. The support vector machine (SVM) was adopted to construct a radiomics model, a clinical model, and a radiomics-clinical model for NPVR prediction, respectively. The area under the curve (AUC) and the decision curve analysis (DCA) were performed to evaluate the predictive validity and the clinical usefulness of the model, respectively.

RESULTS

A total of 851 radiomic features were extracted from T2MRI, of which seven radiomics features were screened for NPVR prediction-related radiomics features. The radiomics-clinical model combining radiomics features and clinical parameters showed the best predictive performance in both the internal (AUC = 0.824, 95% CI 0.693-0.954) and external (AUC = 0.773, 95% CI 0.647-0.902) test cohorts, and the DCA also suggested the radiomics-clinical model had the highest net benefit.

CONCLUSIONS

The radiomics-clinical model could be applied to the NPVR prediction of patients with uterine fibroids treated by HIFU to provide an objective and effective method for selecting potential patients who would benefit from the treatment mostly.

Complications of transvaginal radiofrequency ablation of fibroids: A 5-year experience

Introduction

Transvaginal radiofrequency ablation is a relatively noninvasive approach for the treatment of fibroids in patients who do not wish to undergo conventional surgery. Information on potential complications of this novel technique is very scarce.

Methods

Retrospective, descriptive, epidemiological study of 115 patients who underwent transvaginal radiofrequency ablation of fibroids and for whom complications were recorded.

Results

We performed 115 transvaginal radiofrequency ablation procedures, we recorded a total of 11 complications (9.6%; 95% CI, 3.8-14.8). Of these, 8 (7.0%) were classified as Clavien-Dindo type I, 1 (0.9%,) as type II, and 2 (1.7%) as type IIIb (severe). No other complications were recorded in a year follow-up.

Conclusion

Transvaginal radiofrequency ablation is a treatment option that makes it possible to treat fibroids that are difficult to manage using other techniques. Few associated complications have been described, and most of them are mild.

Clinical efficacy of ultrasound-guided interventional therapy in patients with benign ovarian cysts: a meta-analysis

This study aimed to explore the clinical efficacy of ultrasound-guided interventional therapy in patients with benign ovarian cysts through meta-analysis. A literature search was performed on PubMed, Web of Science, Embase, CNKI, and WanFang databases to obtain clinical randomized controlled trials on ultrasound-guided interventional therapy for benign ovarian cysts published between 2010 and 2022. A total of 1395 studies were initially retrieved, and finally 12 studies were included for meta-analysis. The results showed that the observation group (ultrasound-guided interventional therapy) had higher treatment effective rate than the control group (conventional laparotomy or laparoscopic cyst resection), but the incidence of adverse reactions was markedly lower. Additionally, the length of hospital stay, intraoperative blood loss, and operation time showed significant lower levels in the observation group. In terms of ovarian function, postoperative luteinizing hormone and follicle-stimulating hormone levels in the observation group were lower than the control group, while oestradiol levels were higher. In conclusion, compared with conventional surgical treatment, ultrasound-guided interventional therapy can significantly improve the clinical effective rate, shorten the hospital stay and reduce intraoperative blood loss. Such therapy can protect ovarian reserve, with high value of clinical promotion.IMPACT STATEMENTWhat is already known on this subject? Main surgical methods for ovarian cysts consist of laparotomy, laparoscopic surgery, and interventional therapy.What the results of this study add? With the advancement of surgical techniques and instruments, many minimally invasive surgeries have been applied to treat ovarian cysts with good clinical results. However, there is no exact evidence to prove its clinical efficacy. Given the lack in this field, we conducted a meta-analysis of all clinical studies of ultrasound-guided interventional therapy for ovarian cysts to evaluate its efficacy and safety.What the implications are of these findings for clinical practice and/or further research? Compared with conventional laparotomic or laparoscopic cyst resection, ultrasound-guided interventional therapy for ovarian cysts significantly improves the treatment effectiveness, shortens the hospital stay and reduces intraoperative blood loss. This therapy with good clinical efficacy also has advantages of small wound, rapid recovery and less adverse reactions, and can protect ovarian reserve. This safe and effective surgical method for ovarian cysts is worth promoting clinically.

Efficacy and Safety of Ultrasound-Guided High-Intensity Focused Ultrasound Ablation in Women With Multiple Uterine Fibroids: An Exploratory Study

OBJECTIVE

The aim of the work described here was to explore the clinical efficacy and safety of ultrasound-guided high-intensity focused ultrasound (USg-HIFU) treatment in women with multiple fibroids and identify the characteristic parameters predicting USg-HIFU efficacy in multiple fibroids.

METHODS

From February 2021 to August 2022, 138 patients with multiple fibroids (group A comprising 125 patients with two to four fibroids and 13 patients with five or more fibroids) and 149 patients with solitary fibroids (group B) were included. HIFU treatment information, efficacy comparisons and adverse events were recorded. A nomogram model of the characteristic parameters used to predict the efficacy of USg-HIFU in multiple fibroids was established.

RESULTS

After USg-HIFU treatment, the statistical comparison of pre-operative versus post-operative symptom scores and fibroid volume in the two groups indicated obvious symptom relief and substantial shrinkage of fibroid volume (all p values <0.001). Nevertheless, group A required more energy and longer treatment and sonication times to achieve a 70% non-perfused volume (NPV) ratio, and had a lower energy efficiency factor than group B (all p values <0.05). No severe complications were observed in either group. The nomogram model included fibroid volume, fibroid location and signal intensity on T2-weighted imaging (T2WI). The area under the receiver operating characteristic curve and the accuracy of the model were 0.698 and 0.686, respectively.

CONCLUSION

USg-HIFU appears to be an effective and safe treatment option for multiple fibroids. Knowledge of the fibroid volume, location and signal intensity on T2WI may help determine the efficacy of USg-HIFU in multiple fibroids.

New trends in non-pharmacological approaches for cardiovascular disease: Therapeutic ultrasound

Significant advances in application of therapeutic ultrasound have been reported in the past decades. Therapeutic ultrasound is an emerging non-invasive stimulation technique. This approach has shown high potential for treatment of various disease including cardiovascular disease. In this review, application principle and significance of the basic parameters of therapeutic ultrasound are summarized. The effects of therapeutic ultrasound in myocardial ischemia, heart failure, myocarditis, arrhythmias, and hypertension are explored, with key focus on the underlying mechanism. Further, the limitations and challenges of ultrasound therapy on clinical translation are evaluated to promote application of the novel strategy in cardiovascular diseases.

Resolution of Pain after Percutaneous Image-Guided Cryoablation of Extraperitoneal Endometriosis

PURPOSE

To retrospectively evaluate the relief of pain after percutaneous image-guided cryoablation of symptomatic extraperitoneal endometriosis (EE).

MATERIAL AND METHODS

From 2017 to 2022, cryoablation of EE was performed at a single institution on a total of 47 lesions in 42 consecutive patients (median age, 37 years; interquartile range [IQR], 33-39.5 years). Patient and procedural characteristics were reviewed retrospectively. Tolerance and outcomes in terms of pain and patient satisfaction were evaluated.

RESULTS

The median follow-up duration was 13.5 months (IQR, 1.1-37.7 months) after cryoablation. The median pain-free survival rate was 93.8% (95% confidence interval [CI], 77.3-98.4) at 6 months and 82.7% (95% CI, 58.8-93.5) after 12 months. Pain decreased from a median of 8/10 (IQR, 7-9) on the visual analog scale to 0/10 (IQR, 0-1) at the last follow-up (P < .0001). The median Patient Global Impression of Change score recorded at the last follow-up was 1/7 (IQR, 1-2). The efficacy rate of cryoablation to avoid secondary surgery was 92.8% (39/42) per patient and 93.6% (44/47) per nodule treated. Four patients (9.5%, 4/42) experienced an adverse event in the days following the procedure, and 1 patient (2%) experienced a severe adverse event.

CONCLUSIONS

Percutaneous cryoablation is safe and effective in significantly reducing pain and obtaining local control of EE.

High-Intensity Focused Ultrasound for Patients With Cervical Intraepithelial Neoplasia 2/3: A Prospective One-Arm Study

The aim of this study was to ascertain the safety of high-intensity focused ultrasound (HIFU) for high-grade cervical intraepithelial neoplasia grade 2/3 (CIN 2/3) in patients with fertility requirements. This was a prospective one-arm study. Consecutive CIN 2/3 patients diagnosed with histopathology were screened, enrolled and treated from September 2019 to September 2020 in the Affiliated Hospital of North Sichuan Medical College. All patients were treated with a combination of HIFU and antiviral treatment with REBACIN. The scheduled follow-up visits were 1 week, 1 mo, 3 mo, 6 mo and 12 mo after surgery. The primary outcomes included cure and human papillomavirus clearance rates. We screened 287 consecutive CIN 2/3 patients in our hospital, 29 of whom were enrolled and treated in this study. The cure rate reached 82.8% at 7 mo after treatment and 96.6% within 1 y. The HPV-negative rate reached 72.4% (21/29) around 6 mo after treatment, with mild side effects during and after the procedure. Our study suggests that in CIN 2/3 study participants with fertility requirements, HIFU + REBACIN therapy is a safe and effective therapeutic option with a high cure rate, HPV clearance and few side effects.

High-intensity focused ultrasound for the treatment of fibroids: A single-center experience in Singapore

Objectives

Uterine fibroids and adenomyosis are common gynecological conditions that often require surgical treatment. Minimally invasive interventions such as ultrasound-guided high-intensity focused ultrasound (USgHIFU) are gaining popularity as they avoid surgical morbidity and conserve the uterus. We present a single-center experience on the use of USgHIFU for the treatment of fibroids and adenomyosis.

Materials and Methods

This was a retrospective study of 167 patients who underwent USgHIFU for uterine fibroids and adenomyosis between July 2018 and December 2020. Relevant demographic data and pre- and post-intervention fibroid volume, symptom severity scores (SSS), and health-related quality of life (QOL) scores were collected and compared. The paired t-test or Wilcoxon signed-rank test was used to compare the difference before and after treatment. P < 0.001 was considered statistically significant.

Results

One hundred and sixty-seven patients with fibroids or adenomyosis were included in this study. The mean age of the cohort was 42-year-old. USgHIFU treatment led to a reduction in mean fibroid volume, improvement in SSS, and health-related QOL scores. The average reduction in mean fibroid volume was 68% and 75% at 6 and 12 months, respectively. There was a significant reduction in SSS (46.9 [pre] vs. 15.6 [post], P < 0.001) and improvement in health-related QOL scores at 6 months (58 [pre] vs. 86 [post], P < 0.001). The re-intervention rate following USgHIFU was 7.7% and successful pregnancy post USgHIFU was reported in 6 patients.

Conclusion

USgHIFU is safe and effective. In women who desire fertility or are not suitable for surgery, it is a good alternative option. It should be included in the armamentarium for the treatment of uterine fibroids and adenomyosis.

Learning Curve of USgHIFU Ablation for Uterine Fibroids: A Multi-Center Prospective Study

OBJECTIVES

To verify the stability of high-intensity focused ultrasound (HIFU) technology and the feasibility of training programs with learning curve cumulative summation (LC-CUSUM).

METHODS

A total of 12 physicians and 720 cases were equally assigned to the learning group and the control group, with 6 physicians and 360 cases per group. The learning group was treated by physicians without HIFU experience and the control group was treated by experienced physicians. Nonperfused volume (NPV) ratio was assessed by contrast-enhanced magnetic resonance imaging. Technical failure was defined as NPV ratio of uterine fibroids <70% and/or major complication, while <80% was set as a stricter standard of training qualification. LC-CUSUM was used to analyze the learning curve.

RESULTS

Physicians with or without HIFU experience in both groups achieved matchable NPV ratios, where a NPV ratio of 92.52% (16.06) was achieved by experienced physicians and 93.82% (16.95) by inexperienced physicians. No major complication was observed. The results of LC-CUSUM analysis showed that, with the standards of the NPV ratio of 70% or 80%, the learning group mastered the technique on the 11th case and the 16th case, respectively, while the control group was stable.

CONCLUSIONS

HIFU technology stayed stable in operation, with good safety and sound effectiveness, and was easy to learn. NPV ratio of 70% was considered as an appropriate indicator of training qualification. HIFU has remarkable prospects in achieving a NPV ratio of ≥80% without safety being compromised.

Ventral hernia after high-intensity focused ultrasound ablation for uterine fibroids treatment: A case report

BACKGROUND

High-intensity focused ultrasound (HIFU) ablation is a minimally invasive approach in gynecology that is used to manage uterine fibroids. Although this procedure is safe and effective, adverse outcomes are becoming a major problem.

CASE SUMMARY

We present a case of ventral hernia that occurred as a rare and delayed complication of HIFU ablation for uterine fibroids treatment. The patient came to the hospital with abdominal bloating that occurred 6 mo after ultrasound-guided HIFU ablation for managing uterine fibroids. The ventral hernia, which occurred due to atrophied muscle layers following the procedure, was confirmed by imaging studies and intraoperative findings. She required a hernia repair with mesh and hysterectomy for definitive treatment of uterine fibroid.

CONCLUSION

High-intensity ultrasound ablation should be performed only on appropriate candidates. Patients should be educated about potential complications of the procedure and the possibility of subsequent treatment. Post-procedural long-term follow-up for detecting delayed adverse effects is important.

A review of high-intensity focused ultrasound as a novel and non-invasive interventional radiology technique

High-intensity focused ultrasound (HIFU) is a non-invasive interventional radiology technology, which has been generally accepted in clinical practice for the treatment of benign and malignant tumors. HIFU can cause targeted tissue coagulative necrosis and protein denaturation by thermal or non-thermal effects, guided by diagnostic ultrasound or magnetic resonance imaging, without destruction of the normal adjacent tissue, under sedation or general anesthesia. HIFU has become an important alternative to standard treatments of solid tumors, including surgery, radiation, and medications. The aim of this review is to describe the development, principle, devices, and clinical applications of HIFU.

Predictive value of image indexes of B-mode and power Doppler sonography on the efficacy of high intensity focused ultrasound ablation for uterine fibroids

OBJECTIVE

To investigate the value of the image indexes of B-mode and power Doppler sonography in predicting the therapeutic efficacy of high intensity focused ultrasound (HIFU) ablation for uterine fibroids.

MATERIALS AND METHODS

Two hundred and three patients with a solitary uterine fibroid were enrolled in this study. Every patient underwent transvaginal sonography (TVS) and magnetic resonance imaging (MRI) before HIFU. The patients were divided into hypointense, isointense and hyperintense fibroid groups based on T2 weighted MR imaging characteristics, and ultrasonic image indexes of the fibroids in different groups were compared. Multiple linear regression analysis was used to evaluate the correlation between ultrasonic image indexes and energy efficiency factor (EEF), non-perfused volume (NPV) ratio of uterine fibroids.

RESULTS

Among them, 72 patients had a hypointense fibroid, 70 had an isointense fibroid and 61 had a hyperintense fibroid. Significant differences were observed in the ultrasound imaging gray scale value difference between the myometrium and uterine fibroids (GSmyo-fib), the ultrasound imaging gray scale value ratio of fibroids over the myometrium (GSfib/myo), and the ratio of power Doppler pixel area to fibroid area (PDPA/FA) among the three groups (p < 0.05). Linear regression analysis showed that the PDPA/FA and the location of fibroids were the factors affecting the NPV ratio, a model for predicting the NPV ratio was established.

CONCLUSIONS

A model with the PDPA/FA for NPV ratio could be used to predict the therapeutic efficacy of HIFU for fibroids.

High-intensity focused ultrasound therapy for pediatric and adolescent vulvar lichen sclerosus

OBJECTIVE

The study's objective was to retrospectively evaluate the efficacy and safety of high-intensity focused ultrasound (HIFU) for vulvar lichen sclerosus (VLS) in pediatric and adolescent patients.

METHODS

Pediatric and adolescent patients presenting to our hospital from June 2007 to July 2021, with VLS were retrospectively evaluated. The participants' information, including age, symptoms and vulvar examination, were documented, and they were treated with HIFU. The effectiveness of HIFU and its complications were analyzed.

RESULTS

A total of 36 patients with VLS undergoing HIFU for whom complete follow-up data were available participated in the study. The mean age of the patients at diagnosis was 13.3 ± 4.1 years. All patients successfully underwent HIFU therapy. The mean sonication time was 20.3 ± 8.6 min, and the median treatment energy was 3579.0 J. A few blisters developed in 8 (22.2%) patients and 2 (5.6%) had ulcers. The skin burns were treated medically without scar formation. On average, patients were followed up for 52.0 months after the procedure (a range of 6-175 months). At 6 months after therapy, the total response rate was 91.6%, and 86.6% at 12 months post HIFU. Overall, 16 patients were followed up for more than 5 years. The total response rate was 75%, and the recurrence rate was 12.5%.

CONCLUSIONS

Based on our results, HIFU was demonstrated to be effective and relatively safe for the treatment of VLS in pediatric and adolescent patients, but it is necessary to pay attention to the possible skin burns.

Effectiveness and immune responses of focused ultrasound ablation for cervical intraepithelial neoplasia

PURPOSE

To investigate the safety, efficacy, and the immune responses of focused ultrasound in cervical intraepithelial neoplasia (CIN).

METHODS

Patients with biopsy-confirmed CIN were recruited for focused ultrasound treatment and asked to return during 3-6 and 6-12 months post-treatment to receive cervical cytology, high-risk human papilloma virus (HPV) detection, and colposcopy. The effective rate was evaluated within 3-6 months, whereas the recurrence rate was evaluated within 6-12 months. Cervicovaginal lavage and cervical tissue were sampled before and 3-6 months after treatment. The expression of interferon gamma (IFN-γ), endoplasmic reticulum aminopeptidase 1 (ERAP1), human leucocyte antigen I (HLA-I), cluster of differentiation 4 (CD4), and cluster of differentiation 8 (CD8) in the cervical tissue were observed by immunohistochemistry. Immunoglobulin A (IgA) and interleukin 10 (IL-10) levels in the cervicovaginal lavage were detected by enzyme-linked immunosorbent assay. Comparisons were made in immune analyte levels before and after treatment.

RESULTS

We analyzed the results of 154 patients. The effective rate at 3-6 months was 96.8%. The recurrence rate at 6-12 months was 2.0%. The eradication rate of HPV was 72.4% at 3-6 months and 81.0% at 6-12 months. No serious adverse reactions and complications were observed. After treatment, a higher expression of ERAP1 was observed (p < 0.05). Significant down-regulation of IgA and IL-10 were detected (each p < 0.05). However, the expression of CD4, CD8, HLA-I, as well as the release of IFN-γ, did not reach statistical significance (each p > 0.05).

CONCLUSIONS

Focused ultrasound is an effective and safe therapy for treating CIN, which could improve the local immune milieu of the cervix to some extent.

Physician Experience in Technical Success of Achieving NPVR ≥ 80% of High-Intensity Focused Ultrasound Ablation for Uterine Fibroids: A Multicenter Study

Objective

To evaluate the experience of the physician of the technical success in high-intensity focused ultrasound (HIFU) ablation of uterine fibroids with a nonperfused volume ratio (NPVR) of at least 80%.

Methods

Patients from a 20-center prospective study were enrolled in this study. In this study, among the 20 clinical centers, five centers had physician with >3 years of HIFU experience, and the other 15 centers initiated HIFU therapy <3 years, were defined as the experienced group and the inexperienced group, respectively. Technical success was defined as achieving NPVR ≥ 80% of uterine fibroids with no major complications and it was defined as the successful group; otherwise, it was defined as the unsuccessful group.

Results

A total of 1,352 patients were included at the age of 41.32 ± 5.08 years. The mean NPVR (87.48 ± 14.91%) was obtained in the inexperienced group (86.50 ± 15.76%) and in the experienced group (89.21 ± 13.12%), respectively. The multivariate analysis showed that the volume of uterus, location of fibroids, and physician experience were significantly correlated with technical success (p < 0.05). In the experienced group, 82.20% of uterine fibroids obtained NPVR ≥ 80%, compared with 75.32% in the inexperienced group, and the difference was significant (p = 0.003). The technical success rate of the experienced group was 82.00% which was higher than 75.20% of the inexperienced group (p = 0.004).

Conclusion

In technical success of achieving NPVR ≥ 80%, experience of the physician was positively correlated with technical success; NPVR and major complications for the inexperienced group were comparable to those of the experienced group from a clinical perspective; inexperienced physicians could reach NPVR ≥ 80% of sufficient ablation and were trustworthy in efficacy. Smaller uterus and fibroids of anterior wall were correlated with better technical success; experienced physicians still have better technical success when choosing patients with larger uterus, contributing to clinical decision-making and patient referral.

Multidisciplinary management to optimize outcome of ultrasound-guided high-intensity focused ultrasound (HIFU) in patients with uterine fibroids

Little is known about the specific anaesthesiological and multidisciplinary management of high-intensity focused ultrasound (HIFU) in uterine fibroids. This observational single-center study is the first reporting on an interdisciplinary approach to optimize outcome following ultrasound (US)-guided HIFU in German-speaking countries. A sample of forty patients with symptomatic uterine fibroids was treated by HIFU. Relevant treatment parameters such as total treatment time for intervention, anaesthesia, and sonication time as well as total energy, body temperature, peri-interventional medication and complications were analyzed. Interventional variables did not correlate significantly either with opioid dose or with body temperature. The average fibroid volume reduction rate was 37.8% ± 23.5%, 48.5% ± 22.0% and 70.2% ± 25.5% after 3, 6 and 12 months, respectively. No major anaesthesiological complications occurred apart from an epileptic seizure prior to HIFU treatment in one patient. Peri-procedural hyperthermia (> 37.5 °C) occurred in two patients. Post-procedural two patients experienced a sciatic nerve irritation up to one year; one patient with very large treated fibroid experienced strong short-lasting post-procedural pain. There were two complication-free pregnancies of HIFU-treated patients. Multidisciplinary management is crucial to optimize safety and outcome of US-guided HIFU for uterine fibroids. Peri-procedural pain and temperature management are critical points where an adequate collaboration between anesthesiologist and interventionalist is mandatory.

Temperature-dependent dielectric properties of human uterine fibroids over microwave frequencies

Microwave ablation is under investigation as a minimally-invasive treatment for uterine fibroids. Computational models play a vital role in the development, evaluation and characterization of candidate ablation devices. The temperature-dependent dielectric properties of fibroid tissue are essential for accurate computational modeling.Objective:To measure the broadband temperature-dependent dielectric properties of uterine fibroids excised during hysterectomy procedures.Methods: The open-ended coaxial probe method was employed for measuring the broadband dielectric properties of freshly excised human uterine fibroid samples (n = 6) obtained from an IRB-approved tissue bank. The dielectric properties (relative permittivity,ε_r, and effective electrical conductivity,σ_eff) were evaluated at temperatures ranging from 23 °C-150 °C, over the frequency range of 0.5-6 GHz. Linear piecewise parametrization with respect to temperature and quadratic parametrization with respect to frequency was applied to characterize broadband temperature-dependent dielectric properties of fibroid tissue.Results: The baseline room temperature values ofε_rvary from 57.5 ± 5.29 to 44.5 ± 5.77 units andσ_effchanges from 0.91 ± 0.19 to 6.02 ± 0.7 S m^-1over the frequency range of 0.5-6 GHz. At temperatures close to the water vaporization point,ε_r, drops considerably i.e. to 12%-14% of its baseline value for all measured frequencies.σ_effvalues initially rise till 98 °C and then fall to 11%-13% of their baseline values at 125 °C for frequencies ≤2.45 GHz. Theσ_efffollows a decreasing trend for frequencies >2.45 GHz and drops to ∼6 % of their baseline room temperature values.Conclusion:The temperature dependent dielectric properties of uterine fibroid tissues over microwave frequency range are reported for the first time in this study. Parametric models of uterine fibroid dielectric properties are also presented for incorporation within computational models of microwave ablation of fibroids.

[Diffusion-weighted magnetic resonance imaging instead of contrast-enhanced imaging for evaluating immediate therapeutic efficacy of high-intensity focused ultrasound ablation of adenomyosis]

OBJECTIVE

To explore the feasibility of diffusion-weighted magnetic resonance imaging (DWI) instead of contrast-enhanced (CE) imaging for evaluation of the immediate therapeutic efficacy of high-intensity focused ultrasound (HIFU) ablation for treatment of adenomyosis.

METHODS

We retrospectively analyzed the data of 29 patients aged 40.5 ± 5.4 years under going HIFU treatment for adenomyosis in our hospital between December, 2017 and July, 2020. The patients received MRI examination both before and within 24 h after the operation. Two observers analyzed the morphology of the ablation area on DWI and classified the lesions into type 1 (spot-like or no obvious signal intensity changes), type 2 (patchy signal intensity changes) and type 3 (ring-like signal intensity changes). The inter- and intra-observer reliability of morphological assessment was assessed using kappa test. The volume of necrotic tissues following the ablation was measured with both DWI and CE imaging, and the consistency of the measurements and the inter- and intra-observer reliability of DWI-based measurements were evaluated using Bland-Altman plot tests.

RESULTS

The median volume of necrotic tissues was 36.9 cm3 (range 16.4-65.5 cm3) following ablation of the 29 lesions. DWI findings identified 24-25 (82.8%-86.2%) lesions with type 2 or 3 signal changes following the ablation with measurable necrotic tissue volume. On DW images, the Kappa value of intra- and inter-observer reliability for morphological classification of the ablation area reached 0.798 (P=0.000) and 0.933 (P= 0.000), respectively. Bland-Altman plots showed a good consistency of the necrotic volumes measured by CE and at DWI with a strong inter- and intra-observer reliability of DWI-based volume measurements (with only one point outside the range of 95% limits of agreement). The remaining 4 or 5 lesions, which presented with type 1 signal changes following ablation, were all small in size (the largest was only 18.61 cm3) and showed poor therapeutic responses to the ablation.

CONCLUSION

DWI-based morphological assessment and necrotic tissue volume measurement can replace CE imaging for assessment of the immediate therapeutic efficacy of HIFU ablation for treatment of adenomyosis.

Factors influencing the clinical efficacy of high-intensity focused ultrasound in the treatment of non-neoplastic epithelial disorders of the vulva: a retrospective observational study

BACKGROUND

High-intensity focused ultrasound (HIFU) is an important method for treating non-neoplastic epithelial disorders of the vulva (NNEDV), but the factors affecting the efficacy of HIFU for NNEDV treatment remain unclear.

OBJECTIVE

To determine the factors influencing the clinical efficacy of HIFU in the treatment of NNEDV.

METHODS

A retrospective observational study of 186 NNEDV patients treated with HIFU was performed to evaluate the therapeutic effect, and the relationship between treatment efficacy and clinicopathological factors was analyzed.

RESULTS

NNEDV signs and symptoms were effectively improved and relieved after HIFU treatment. The total effective and recurrent rates were 95.16% and 4.52%, respectively. Younger patients with shorter disease courses, mild itching, or peri-vulvar lesions had better therapeutic effects, and patients with anxiety and/or depression had worse treatment outcomes.

CONCLUSION

The therapeutic effect of HIFU on NNEDV is not only related to the itching degree, age, or disease course but is also closely related to lesion location as well as anxiety and depression in patients.

The effect of ultrasound-guided high-intensity focused ultrasound treatment for cesarean scar pregnancy on ovarian reserve

OBJECTIVE

The aim of this study was to evaluate changes in anti-Müllerian hormone (AMH) levels after ultrasound-guided high-intensity focused ultrasound (USgHIFU) treatment of cesarean scar pregnancy (CSP).

METHODS

A retrospective case series study was conducted in the Affiliated Hospital of North Sichuan Medical College. Thirty-two women with cesarean scar pregnancy who met the inclusion criteria were enrolled in the study between January 2018 and December 2019. All patients underwent USgHIFU treatment with or without suction curettage. Intraoperative blood loss in suction curettage and hysteroscopy procedures, time to return of β-human chorionic gonadotropin (β-hCG) to normal levels, and time to recovery of normal menstruation were recorded. AMH levels before and 3 months after HIFU treatment were compared to determine whether USgHIFU treatment affected ovarian reserve.

RESULTS

AMH levels before and 3 months after HIFU ablation were 1.87 ± 1.19 ng/ml and 1.90 ± 1.17 ng/ml, respectively. There was no significant difference in AMH levels between the two-time points (p > .05). The median volume of intraoperative blood loss was 20 ml, the median time for the serum β-hCG level to return to normal was 35.5 days, and the median time of menstruation recovery was 39 days.

CONCLUSIONS

USgHIFU treatment for CSP was effective and safe without affecting ovarian reserve.

Uterine fibroid vascularization: from morphological evidence to clinical implications

Uterine fibroids are the most common cause of solid pelvic tumours, occurring in 20-30% of fertile women and presenting clinical complications that seriously affect women's health. They commonly cause severe symptoms, such as heavy, prolonged menstrual bleeding and anaemia. The study of microscopic and macroscopic vascular aspects of uterine fibroids is important for understanding the clinical manifestations of uterine fibroids, for predicting the effectiveness of alternative treatments to surgery, i.e. uterine artery embolization, for improving surgery outcomes and for carrying out a differential diagnosis with other benign conditions, e.g. adenomyosis, or malignancy, e.g. leiomyosarcoma, and to develop new therapeutic approaches. In this review, current knowledge of how the vascular network and angiogenesis are implied in the formation of uterine fibroids and in the pathogenesis of related symptoms is explored, and evidence on the role of ultrasound in evaluating fibroid vascularization is summarized. This review combines anatomical, morphological and biomolecular information related to angiogenic mechanisms with diagnostic and clinical information, highlighting the various interconnections. Uterine and fibroid vascularization need further investigation to gain a deeper understanding of the pathogenetic elements that lead to the formation of uterine fibroids and their clinical manifestations.

Efficacy of High-Intensity Focused Ultrasound Combined With GnRH-a for Adenomyosis: A Systematic Review and Meta-Analysis

Objective: High-intensity focused ultrasound (HIFU) is an innovative non-invasive technology used for adenomyosis. Gonadotropin-releasing hormone agonist (GnRH-a) is a hormone commonly used for adenomyosis. We investigated and assessed the efficacy of HIFU combined with GnRH-a for adenomyosis. Methods: For this systematic review and meta-analysis, we searched Pubmed, Cochrane Library, Web of Science, Embase, CNKI, WanFang, and VIP databases for relevant articles published in Chinese or English that compared HIFU combined with GnRH-a vs. HIFU alone in patients with adenomyosis. The last literature search was completed on January 31, 2021. Two reviewers independently assessed study eligibility and assessed risk of bias. Another two reviewers extracted the data. The RevMan5.3 software was used for the data analysis. Changes in volume of the uterine and adenomyotic lesion were defined as the primary outcomes. The secondary outcomes were visual analog scale (VAS) scores for dysmenorrhea, menstrual volume scores, serum CA125 levels, and recurrence rate. This study is registered with PROSPERO (CRD42021234301). Results: Three hundred and ninety potentially relevant articles were screened. Nine studies with data for 766 patients were finally included. Compared with the HIFU alone group, the HIFU combined with GnRH-a group had a higher rate of uterine volume reduction (MD 7.51, 95% CI 5.84-9.17, p < 0.00001), smaller adenomyotic lesion volume (MD 4.11, 95% CI 2.93-5.30, p < 0.00001), lower VAS score for dysmenorrhea (MD 1.27, 95% CI 0.54-2.01, p = 0.0007) and menstrual volume score (MD 0.88, 95% CI 0.73-1.04, p < 0.00001), and lower CA125 level (SMD 0.31, 95% CI 0.05-0.56, p = 0.02) after the procedure. The recurrence rate in the HIFU combined with GnRH-a group was lower than that in the HIFU alone group (RR 0.28, 95% CI 0.10-0.82, p = 0.02). Conclusions: Compared with HIFU treatment alone, HIFU combined with GnRH-a for the treatment of adenomyosis has greater efficacy in decreasing the volumes of the uterine and adenomyotic lesions and alleviating symptoms. However, since the number of the included studies was too small and most of them were written in Chinese, this conclusion needs to be referenced with caution. And the long-term evidence of its efficacy is still insufficient. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/ identifier [CRD42021234].

Ultrasound-Guided High-Intensity Focused Ultrasound for Devascularization of Uterine Fibroid: A Feasibility Study

This study aimed to establish the feasibility of ultrasound-guided high-intensity focused ultrasound (USgHIFU) for devascularization of uterine fibroids. Ultrasound color Doppler flow imaging (CDFI) and B-mode imaging were used to target fibroid vascularity. The vessels were covered and ablated by high-intensity focused ultrasound spots. In this study, 42 fibroids with a volume of 66.98 ± 4.00 cm³ were treated. No blood flow was detected by post-treatment CDFI in 40 fibroids. The 6-mo non-perfusion volume rate was 75.23% ± 34.77% (n = 40). The mean shrinkage in fibroid volume was 38.20% and 43.89%, respectively, at 1 and 6 mo after treatment (p < 0.001). The uterine fibroid symptom and quality of life scores were reduced by 9.43% at 1 mo and 26.66% at 6-mo after treatment (p < 0.001). No serious adverse event was observed. This study demonstrates the feasibility of USgHIFU-induced fibroid devascularization, and more studies are required for the evaluation of safety and efficacy.

Pregnancy outcomes after ultrasound-guided high-intensity focused ultrasound (USgHIFU) for conservative treatment of uterine fibroids: experience of a single institution

OBJECTIVE

To assess the impact of ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation for uterine fibroids on fertility.

MATERIAL AND METHODS

A retrospective observational study was conducted of 560 reproductive-age women with symptomatic uterine fibroids who underwent USgHIFU therapy at Mútua Terrassa University Hospital, Spain, between February 2008 and February 2018. We analyzed pregnancy outcomes including time to conception, pregnancy approach, gestational age, delivery mode, neonatal outcomes and complications during pregnancy and delivery.

RESULTS

After USgHIFU treatment, 71 pregnancies were obtained in 55 patients. Of these, 58 (82%) cases were natural pregnancies and 13 (18%) were in vitro fertilization (IVF) pregnancies. The median time to conception was 12 (range 1-72) months. There were 43 (61%) successful deliveries, including a twin gestation, 22 (31%) spontaneous abortions and 6 (8%) therapeutic abortions. The rate of full-term deliveries was 91% (39/43) and the remaining 9% (4/43) were preterm deliveries. Of the 44 live births, 25 (57%) were born vaginally and 19 (43%) by cesarean section. The complications reported included 3 women with retained placenta (7%), 2 with placenta previa (5%) and 1 with severe preeclampsia (2%). The mean birth weight was 3.1 (range: 1.4-4.3) kg, and except for a baby born with a tetralogy of Fallot, all newborns developed well without complications during postpartum and breastfeeding.

CONCLUSION

Patients undergoing USgHIFU treatment of uterine fibroids can achieve full-term pregnancies with few intrapartum or postpartum complications. More studies are required to compare fertility and perinatal outcomes between patients who underwent or not USgHIFU.

500 Cases of High-intensity Focused Ultrasound (HIFU) Ablated Uterine Fibroids and Adenomyosis

OBJECTIVE

Clinical outcomes of 500 high-intensity focused ultrasound (HIFU)-treated uterine fibroids and adenomyosis are analyzed and presented.

MATERIALS AND METHODS

This is a retrospective cross-sectional analysis from a single tertiary medical center. From April 2015 to October 2018, 546 cases were enrolled for the study. After excluding 46 patients with less than 3 months of follow-up period, there were 404 fibroids, 149 adenomyosis and 53 mixed conditions entered for analysis. The patients' uterine fibroids and adenomyosis were treated by HIFU according to Chongqing Haifu protocol, with 12 cm diameter transducer of focal length 10-16  cm at 0.8 or 1.6 MHz T2-weight MRI imaging was rendered prior to and 3 month post treatment to assess lesion volume change using non-perfusion volume, which was the primary outcome. Secondary outcomes including quality of life, subjective satisfaction, adverse events and pregnancy rate were determined using self-reported questionnaires. The mean follow up period ranged from 3 to 38 months with an average of 21 months.

RESULTS

Three months after HIFU-treated uterine fibroids and adenomyosis, the lesion size reduced 40.2% and 46.3%, respectively. Symptoms all improved with better quality of life for the fibroid group, while those with adenomyosis or combined diseases benefit the most from pain control. Serum CA125 decreased significantly for all studied groups, and LDH only showed improvement for fibroids group. Number of adverse events is comparable to Chongqing data (approximately 10.2%), with mostly mild and self-resolving conditions. No permanent sequelae or death was documented. Twelve pregnancies are reported in this cohort.

CONCLUSION

HIFU is safe and effective in treating uterine fibroids and adenomyosis. The results are reproducible if standardized treatment schedules are followed. It is a promising treatment alternative with the advantages of precision, non-invasiveness, rapid recovery and readiness for pregnancy.

Comparison of efficacy and safety of high-intensity focused ultrasound at different powers for patients with vulvar lichen simplex chronicus

OBJECTIVE

To compare the efficacy and safety of the treatment of vulvar lichen simplex chronicus (VLSC) using high-intensity focused ultrasound (HIFU) at different powers.

METHODS

This retrospective study included 152 patients with VLSC. Among these patients, 70 were treated with HIFU at low power (level 2), and 82 were treated at normal power (level 3). The treatment responses, recurrence rates and intra- and postoperative complications were all compared.

RESULTS

No statistically significant differences were found between the two groups in age, disease course, menopause status, lesion size and severity of symptoms. All patients received one session of HIFU therapy, and the treatment process was successful. No difference was found in the total response rate between the two groups at 1 (85.7% versus 87.8%, p = .35), 6 (80% versus 80.5%, p = .65) and 12 (80% versus 80.5%, p = .73) months after HIFU therapy. No significant difference was observed in the recurrence rate between the two groups at 6 (5.7% versus 9.8%, p = .36) and 12 (22.9% versus 26.8%, p = .57) months after HIFU treatment. Patients in the low-power group had a lower incidence of blisters (10% versus 23.3%, p = .04).

CONCLUSION

Based on our results, low-power HIFU treatment can achieve a therapeutic effect similar to normal power HFU treatment for VLSC, but its incidence of side effects is lower.

Image-guided thermal ablation in the management of symptomatic adenomyosis: a systematic review and meta-analysis

OBJECTIVE

To evaluate the clinical effects of image-guided thermal ablation for the treatment of symptomatic adenomyosis (AD).

DATA SOURCES

We searched PubMed, Web of Science, Cochrane Library, EMBASE, ClinicalTrials.gov and Google Scholar for literature from January 2000 to September 2020.

METHODS OF STUDY SELECTION

We included all studies reporting clinical outcomes of image-guided thermal ablation for AD, involving high-intensity focused ultrasound (HIFU), percutaneous microwave ablation (PMWA) and radiofrequency ablation (RFA). Two independent researchers performed study selection according to the screening criteria.

RESULTS

A total of 38 studies representing 15,908 women were included. Compared with those at baseline, the visual analog scale scores, the symptom severity scores and the menorrhagia severity scores decreased significantly after these thermal ablation therapies. The mean ablation time was 92.18 min, 24.15 min and 31.93 min during HIFU, PMWA and RFA, respectively. The non-perfused volume ratio of AD was 68.3% for HIFU, 82.5% for PMWA and 79.2% for RFA. The reduction rates of uterine volume were 33.6% (HIFU), 46.8% (PMWA) and 44.0% (RFA). The reduction rates of AD volume were 45.1% (HIFU), 74.9% (PMWA) and 61.3% (RFA). The relief rates of dysmenorrhea were 84.2% (HIFU), 89.7% (PMWA) and 89.2% (RFA). The incidence of minor adverse events was 39.0% (HIFU), 51.3% (PMWA) and 3.6% (RFA). The re-intervention rates were 4.0% (HIFU) and 28.7% (RFA). The recurrence rate was 10.2% after HIFU. The pregnancy rates were 16.7% (HIFU), 4.93% (PMWA) and 35.8% (RFA).

CONCLUSION

Image-guided HIFU, PMWA and RFA may be effective and safe minimally invasive therapies for symptomatic AD.

Early versus late hysteroscopic resection after high-intensity focused ultrasound for retained placenta accreta

Objective: To compare early and late hysteroscopic resection after high-intensity focused ultrasound (HIFU) for retained placenta accreta. Methods: This retrospective study included 63 women with retained placenta accreta who were treated with HIFU combined with hysteroscopic resection. They were divided into an early group (n = 40) and a late group (n = 23), depending on the time between the HIFU and the hysteroscopic resection. The number of sessions of hysteroscopy needed, adverse events, menstrual recovery, and reproductive outcomes were compared. Results: The mean largest diameter of the retained placenta accreta was 67.6 ± 14.0 mm and 71.6 ± 23.6 mm in each group (p = .47), respectively. In the early group, the first hysteroscopic procedure was done at a mean interval of 2.7 ± 1.4 days after HIFU ablation, while in the late group, the interval was 34.7 ± 15.0 days (p < .001). The rate of complete resection of placenta residue after one hysteroscopic procedure in the late group was 73.9% (17/23). This was significantly higher than in the early group, where the rate was 45% (p = .03). During the follow-up, there was no difference in menstrual recovery and pregnancy outcomes between the groups. Conclusion: This study was the first to compare the effects and safety of early and late hysteroscopic resection after HIFU for retained placenta accreta. Late hysteroscopic resection seems to increase the rate of complete resection of retained placenta accreta after one hysteroscopic procedure.

A comparison of results following the treatment of placenta accreta and placenta increta using high-intensity focused ultrasound followed by hysteroscopic resection

OBJECTIVE

To compare the safety and efficacy of high-intensity focused ultrasound (HIFU) followed by hysteroscopic resection for different placenta accreta spectrum disorders.

MATERIALS AND METHODS

Thirty-four patients with placenta accreta, placenta increta, or placenta percreta were treated with USgHIFU from January 2016 to December 2019 and were retrospectively reviewed. The patients were classified into three categories according to the relationship between the trophoblastic villi and the myometrium, based on magnetic resonance imaging (MRI). Fifteen patients were classified as placenta accreta, 17 patients were classified as placenta increta, and 2 were classified as placenta percreta. All patients completed follow-up. Treatment efficacy and safety were evaluated.

RESULTS

No significant differences in baseline characteristics and results of HIFU ablation were observed between the patients with placenta accreta and those with placenta increta. The return of HCG levels to normal was longer in patients with placenta accreta compared with patients with placenta increta, while no significant difference was observed in the amount of intraoperative blood loss, the return of normal menstruation and the length of hospital stay.

CONCLUSIONS

HIFU treatment followed by hysteroscopic resection is safe and effective in the treatment of patients with placenta accreta and placenta increta.

Ultrasound-guided Microwave Ablation in the Management of Symptomatic Uterine Myomas: A Systematic Review and Meta-analysis

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the clinical effects and safety of ultrasound-guided microwave ablation (MWA) for the treatment of symptomatic uterine myomas.

DATA SOURCES

We searched PubMed, Web of Science Core Collection, Cochrane Library, Embase, Scopus, and Google Scholar for studies from January 2000 to January 2021.

METHODS OF STUDY SELECTION

We included all studies that reported the clinical outcomes of ultrasound-guided MWA in women with symptomatic uterine myomas. Two researchers conducted the study selection according to the screening criteria.

TABULATION, INTEGRATION, AND RESULTS

We evaluated the risk of bias and evidence quality using the Newcastle-Ottawa scale. Two researchers independently extracted information from the included studies. We extracted the standardized mean difference (SMD) and pooled proportion with a 95% confidence interval (CI) for the outcome measures of interest. A total of 10 studies representing 671 patients were included. The Uterine Fibroid Symptom and Quality of Life (UFS-QoL) questionnaire was used to assess the clinical effects. Compared with baseline, the UFS scores decreased significantly (SMD 3.37; 95% CI, 2.27-4.47; p <.001; reduction rate 65.9%), QoL scores increased significantly (SMD -3.12; 95% CI, -3.93 to -2.30; p <.001; rate of increase 72.0%), and hemoglobin concentration increased significantly (SMD -2.13; 95% CI, -3.44 to -0.81; p = .002; rate of increase 30.3%) at follow-up. The mean operation time was 34.48 minutes (95% CI, 22.82-46.13; p <.001). The rate of reduction in myoma volume after MWA was 85.3% (95% CI, 82.7%-88.0%, p <.001). No major adverse event was reported, and the incidence of minor adverse events was 21.1% (95% CI, 15.1%-27.0%, p <.001).

CONCLUSION

Ultrasound-guided MWA is an effective and safe minimally invasive therapy for symptomatic uterine myomas.

Differences in the therapeutic effects of high-intensity focused ultrasound (HIFU) ablation on uterine fibroids with different shear wave velocity (SWV): a study of histopathological characteristics

OBJECTIVE

To explore correlations between the therapeutic effect of high intensity focused ultrasound (HIFU) and histopathological characteristics of uterine fibroids with different Shear Wave Velocity (SWV) values.

METHODS

A retrospective study was conducted on 36 women (43 fibroids) who had undergone high intensity focused ultrasound (HIFU) uterine fibroids ablation between January 2019 and January 2020. Preoperative fibroids tissue sections were obtained for histopathological examination. The pathological sections were stained with Masson-trichrome, and were observed and imaged under a Low-power microscope (4 × 10), while the smooth muscle cell (SMC) and collagen fiber content were semi-quantitatively measured. Preoperative fibroid SWV was measured using the Virtual Touch tissue quantification (VTQ) technique. Within one month after HIFU ablation, all patients had undergone a pelvic cavity MRI examination, which measured the size, volume, and non-perfused volume (NPV) of the fibroids. The formula: the ablation rate = NPV/target fibroid volume × 100% was used to calculate the ablation rate of the uterine fibroids. Correlation analysis of SWV values, HIFU ablation rate, along with the smooth muscle cell (SMC) and collagen fiber content, were conducted using the Spearman's correlation test.

RESULTS

The collagen fiber and SMC content of the preoperative fibroids were 32.09 ± 15.90%/view and 37.61 ± 15.32%/view, respectively. Preoperative fibroid SWV value was 3.56 ± 0.71 m/s. Preoperative fibroid SWV was negatively correlated with SMC content (r = -0.445, p = 0.003), but positively correlated with collagen fiber content (r = 0.454, p = 0.002). The ablation rate was negatively correlated with collagen fiber content (r = -0.377, p = 0.013), but positively correlated with SMC content (r = 0.402, p = 0.007).

CONCLUSION

Differences in histopathological characteristics may be important factors that induce differences in the therapeutic effects of HIFU ablation on uterine fibroids with different SWV values.

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

OBJECTIVE

To investigate the prevalence of pelvic adhesions in patients with uterine fibroids after high-intensity focused ultrasound (HIFU) treatment, then analyze the influencing factors of pelvic adhesions.

MATERIALS AND METHODS

From October 2010 to March 2020, a total of 2619 patients with uterine fibroids underwent either hysterectomy, myomectomy, or cesarean section in Suining Central Hospital of Sichuan province. Of the 2619 patients, 810 were excluded because of a documented history of either pelvic infections, endometriosis, prior abdominopelvic surgery, or gynecological malignancies; 1809 patients were enrolled and the data were retrospectively assessed for the prevalence and patterns of pelvic adhesions. Among them, 96 patients with uterine fibroids had had prior HIFU treatment (HIFU group), 1713 patients had not had HIFU or surgical treatments (control group).

RESULTS

Among the 96 patients in the HIFU group, adhesions were detected in 42 patients, the incidence of pelvic adhesion being 43.75%; the 1713 patients in the control group, adhesions were detected in 619 patients, the prevalence of pelvic adhesion being 36.14%. No statistically significant difference in the incidence of adhesion between the two groups was observed (p = .132), no significant difference in location of pelvic adhesions between the two groups and no significant difference in the severity of adhesions between the two groups was observed (p > .05).

CONCLUSIONS

Based on our results with limited numbers, we concluded that HIFU treatment did not significantly increase the risk of pelvic adhesions.

Transcervical microwave ablation in type 2 uterine fibroids via a hysteroscopic approach: analysis of ablation profiles

Type 2 uterine fibroids are challenging to resect surgically as ≥ 50% volume of myoma lies within the myometrium. A hysteroscopic approach for ablating fibroids is minimally-invasive, but places a considerable burden on the operator to accurately place the ablation applicator within the target. We investigated the sensitivity of transcervical microwave ablation outcome with respect to position of the ablation applicator within 1 - 3 cm type 2 fibroids.Methods:A finite element computer model was developed to simulate 5.8 GHz microwave ablation of fibroids and validated with experiments inex vivotissue. The ablation outcome was evaluated with respect to applicator insertion angles (30°, 45°, 60°) , depth and offset from the fibroid center (±2 mm for 3 cm fibroid and ±1 mm for 1 cm fibroid) with 35 W and 15 W applied power for 3 cm and 1 cm fibroids, respectively. Power deposition was stopped when thermal dose of 40 cumulative equivalent minutes at 43 °C (CEM43) was accrued in adjacent myometrium.Results:Within the range of all evaluated insertion angles, depths and offsets, the ablation coverage was less sensitive to variation in angle as compared to depth and offset, and ranged from 34.9 - 83.6% for 3 cm fibroid in 140 - 400 s and 34.1 - 67.9% for 1 cm fibroid in 30 - 50 s of heating duration. Maximum achievable ablation coverage in both fibroid cases reach ∼ 90% if thermal dose is allowed to exceed 40 CEM43 in myometrium.Conclusion:The study demonstrates the technical feasibility of transcervical microwave ablation for fibroid treatment and the relationship between applicator position within the fibroid and fraction of fibroid that can be ablated while limiting thermal dose in adjacent myometrium.

A Journey from Learning a Noninvasive High-intensity Focused Ultrasound Surgical Treatment for Gynecological Diseases to Providing High-intensity Focused Ultrasound Services in Hong Kong

This paper reflects a Hong Kong doctors group's journey to learn the high-intensity focused ultrasound (HIFU) ablation treatment for gynecological diseases in China. The procedures of HIFU ablation for fibroids, adenomyosis, and other gynecological diseases are described. After completing our training, the authors applied the HIFU ablation techniques they have learned to establish an outpatient HIFU clinic and provided HIFU ablation treatment in Hong Kong. This paper describes their early experience in providing HIFU services.

Application of low-intensity pulsed therapeutic ultrasound on mesenchymal precursors does not affect their cell properties

Ultrasound is considered a safe and non-invasive tool in regenerative medicine and has been used in the clinic for more than twenty years for applications in bone healing after the approval of the Exogen device, also known as low-intensity pulsed ultrasound (LIPUS). Beyond its effects on bone health, LIPUS has also been investigated for wound healing of soft tissues, with positive results for various cell processes including cell proliferation, migration and angiogenesis. As LIPUS has the potential to treat chronic skin wounds, we sought to evaluate the effects produced by a conventional therapeutic ultrasound device at low intensities (also considered LIPUS) on the migration capacity of mouse and human skin mesenchymal precursors (s-MPs). Cells were stimulated for 3 days (20 minutes per day) using a traditional ultrasound device with the following parameters: 100 mW/cm2 with 20% duty cycle and frequency of 3 MHz. At the parameters used, ultrasound failed to affect s-MP proliferation, with no evident changes in morphology or cell groupings, and no changes at the cytoskeletal level. Further, the migration and invasion ability of s-MPs were unaffected by the ultrasound protocol, and no major changes were detected in the gene/protein expression of ROCK1, integrin β1, laminin β1, type I collagen and transforming growth factor β1. Finally, RNA-seq analysis revealed that only 10 genes were differentially expressed after ultrasound stimulation. Among them, 5 encode for small nuclear RNAs and 2 encode for proteins belonging to the nuclear pore complex. Considering the results overall, while the viability of s-MPs was not affected by ultrasound stimulation and no changes were detected in proliferation/migration, RNA-seq analysis would suggest that s-MPs do respond to ultrasound. The use of 100 mW/cm2 intensity or conventional therapeutic ultrasound devices might not be optimal for the stimulation the properties of cell populations. Future studies should investigate the potential application of ultrasound using variations of the tested parameters.