Advances in Adenomyosis Treatment: High-Intensity Focused Ultrasound, Percutaneous Microwave Therapy, and Radiofrequency Ablation.

Background/Objectives: Adenomyosis is a debilitating gynecologic condition that affects both multiparous older women and nulliparous younger women, inducing a variety of symptoms such as dysmenorrhea, menorrhagia, and infertility. Thermal ablation techniques are new procedures that have been proposed for the treatment of adenomyosis. They include high-intensity focused ultrasound (HIFU), percutaneous microwave ablation (PMWA), and radiofrequency ablation (RFA). Because thermal ablation techniques are minimally invasive or noninvasive, fertility is not impaired while symptoms improve. In addition, hospital stays and financial costs are generally reduced, increasing the interest in these alternative management options. Methods: In this narrative review, we conducted a thorough literature search of PubMed/Medline from the database inception to September 2022. In our search, we focused on noninvasive treatment methods such as HIFU ablation, RFA ablation, and PMWA as well as adenomyosis-specific terms and noninvasive techniques (ultrasonography, ultrasound, or magnetic resonance imaging). The queries were a combination of MeSH terms and keywords. The search was limited to the English language. Abstracts were screened according to their content, and relevant articles were selected. Results: Overall, the results showed that the above-mentioned ablation techniques are effective and safe in providing adenomyosis treatment. Lesion size and uterus volume are reduced, leading to considerable symptom alleviation with all three methods. Positive results concerning safety and fertility preservation have been described as well. Conclusions: Nonetheless, more research is required in this field to compare the efficacy and safety of different ablation techniques with traditional therapies. Such research will help improve these procedures and their associated decision-making processes.

Comparative study of HIFU partial gland ablation and robot-assisted radical prostatectomy for localized prostate cancer: an evidence-based approach.

PURPOSE: This research aims to use a data-driven analytical method to compare the effectiveness of High-Intensity Focused Ultrasound (HIFU) partial gland ablation with Robot-Assisted Radical Prostatectomy (RARP) for treating localized prostate cancer, evaluating variations in treatment results. METHODS: We performed a systematic review of the literature, covering key databases including the Cochrane Library, PubMed, EMBASE, Web of Science, and Google Scholar, with the latest information updated until August 2024. We utilized Stata 18 for data analysis, computing weighted mean differences (WMDs) for continuous data and odds ratios (ORs) for categorical data, with all results reported alongside 95% confidence intervals (CIs). Additionally, the studies included were evaluated using the Newcastle-Ottawa Scale (NOS). RESULTS: This meta-analysis incorporated data from three paired studies, encompassing a total of 1,503 patients. Patients treated with HIFU experienced a shorter hospital stay (WMD = -2.78, 95%CI -5.14,-0.43; p = 0.02) compared to those who received RARP. Additionally, evaluations at 3 and 12 months post-surgery revealed that the HIFU group exhibited better recovery in urinary continence and sexual function than the RARP group. However, there were no notable disparities in complication rates (OR = 1.48, 95%CI 0.92,2.40; p = 0.110) and the requirement for salvage therapy (OR = 2.92, 95%CI 0.60,14.33; p = 0.186) between the two treatment methods. CONCLUSION: In conclusion, this meta-analysis appears to suggest potential benefits of HIFU partial gland ablation in possibly reducing the length of hospital stays and seems to indicate that it might be associated with improved recovery in terms of urinary incontinence and sexual function, particularly during the early to mid-term postoperative period. Although the differences in complication rates and the requirement for salvage therapy between the two surgical methods were not statistically significant, the findings provided by this analysis are instrumental in guiding clinical decision-making.

High-Intensity focused ultrasound linear array and system for dermatology treatment.

Dermatological lesions are typically located just a few millimeters below the surface of the skin, which constrains the efficacy of optical-based therapeutic methods such as photothermal and photodynamic therapy due to limited therapeutic depth caused by optical scattering. As an alternative, high-intensity focused ultrasound (HIFU) has been explored for its potential to treat a variety of dermatological conditions because it offers greater flexibility in terms of treatment depth. Since dermatological lesions have a small thickness ranging from 1.5 to 2.0 mm, high-frequency ultrasound (3-10 MHz or higher) is preferred as the focal area is proportional to the operating frequency. However, due to the difficulty in fabricating HIFU array transducers at this frequency range, the majority of HIFU treatments for dermatology rely on single element transducers. Despite the advantages of HIFU, single-element-based HIFU systems are limited in prevalent use for dermatology treatment due to their fixed focal length and mechanical movement for treatment, which can be time-consuming and unsuitable for treating multiple lesions. To address this, we present a newly developed HIFU linear array and 128-channel driving electronics specifically designed for dermatology treatment. This array consists of 128 elements, has a center frequency of 3.7 MHz, an elevation focal length of 28 mm, and an F-number of 1.27 in the elevation direction. The array has a footprint of 71.6 mm by 22 mm. Experiments using a tissue-mimicking phantom have demonstrated that the HIFU linear array and system are capable of transmitting sufficient ultrasound energy to create coagulation inside the phantom.

Advancing Boiling Histotripsy Dose in Ex Vivo And In Vivo Renal Tissues Via Quantitative Histological Analysis and Shear Wave Elastography.

OBJECTIVE: In the context of developing boiling histotripsy (BH) as a potential clinical approach for non-invasive mechanical ablation of kidney tumors, the concept of BH dose (BHD) was quantitatively investigated in porcine and canine kidney models in vivo and ex vivo. METHODS: Volumetric lesions were produced in renal tissue using a 1.5-MHz 256-element HIFU-array with various pulsing protocols: pulse duration tp = 1-10 ms, number of pulses per point ppp = 1-15. Two BHD metrics were evaluated: BHD1 = ppp, BHD2 = tp × ppp. Quantitative assessment of lesion completeness was performed by their histological analysis and assignment of damage score to different renal compartments (i.e., cortex, medulla, and sinus). Shear wave elastography (SWE) was used to measure the Young's modulus of renal compartments in vivo vs ex vivo, and before vs after BH treatments. RESULTS: In vivo tissue required lower BH doses to achieve identical degree of fractionation as compared to ex vivo. Renal cortex (homogeneous, low in collagen) was equal or higher in stiffness than medulla (anisotropic, collagenous), 5.8-12.2 kPa vs 4.7-9.6 kPa, but required lower BH doses to be fully fractionated. Renal sinus (fatty, irregular, with abundant collagenous structures) was significantly softer ex vivo vs in vivo, 4.9-5.1 kPa vs 9.7-15.2 kPa, but was barely damaged in either case with any tested BH protocols. BHD1 was shown to be relevant for planning the treatment of renal cortex (sufficient BHD1 = 5 pulses in vivo and 10 pulses ex vivo), while none of the tested doses resulted in complete fractionation of medulla or sinus. Post-treatment SWE imaging revealed reduction of tissue stiffness ex vivo by 27-58%, increasing with the applied dose, and complete absence of shear waves within in vivo lesions, both indicative of tissue liquefaction. CONCLUSION: The results imply that tissue resistance to mechanical fractionation, and hence required BH dose, are not solely determined by tissue stiffness but also depend on its composition and structural arrangement, as well as presence of perfusion. The SWE-derived reduction of tissue stiffness with increasing BH doses correlated with tissue damage score, indicating potential of SWE for post-treatment confirmation of BH lesion completeness.

Noninvasive high-intensity focused ultrasound for skin brightening efficacy using a topical agent containing glutathione and hyaluronic acid.

BACKGROUND: High-intensity focused ultrasound (HIFU) is well-documented for skin rejuvenation, lifting, and tightening. However, its synergistic effects with topical agents, enhanced by HIFU-induced vibration and heat, remain underexplored. OBJECTIVE: To evaluate clinical and photographic outcomes of HIFU combined with a topical agent versus the topical agent alone. METHOD: This non-randomized controlled trial involved 20 female volunteers (ages 30-55) divided into two groups. Group A (n = 10) received two HIFU sessions combined with a topical agent containing glutathione and hyaluronic acid. Group B (n = 10) received the topical agent alone. Outcomes were assessed using digital photography, patient satisfaction surveys, and the A-One Smart™ system for fine wrinkles, hyperpigmentation, and hydration. Skin brightening was evaluated with the Global Esthetic Improvement Scale (GAIS). RESULTS: Group A showed significant reductions in fine wrinkles (6.25 ± 2.00 mm to 3.10 ± 1.62 mm), improved hyperpigmentation (3.50 ± 0.80 to 2.10 ± 1.05), and increased hydration (28 ± 10 to 55 ± 11) (all p < 0.05). Over two-thirds of Group A reported significant improvements, with no complications. Group B showed minimal, non-significant changes (p > 0.05), with only 30% reporting noticeable improvements. CONCLUSION: Combining HIFU with a topical agent significantly enhances skin quality and brightness without adverse effects.

Future Directions of MR-guided Focused Ultrasound.

MR-guided focused ultrasound (MRgFUS) allows for the incisionless treatment of intracranial lesions in an outpatient setting. While this is currently approved for the surgical treatment of essential tremor and Parkinson's disease, advancements in imaging and ultrasound technology are allowing for the expansion of treatment indications to other intracranial diseases. In addition, these advancements are also making MRgFUS treatments easier, safer, and more efficacious.

Model based deep learning method for focused ultrasound pathway scanning.

The primary purpose of high-intensity focused ultrasound (HIFU), a non-invasive medical therapy, is to precisely target and ablate tumors by focusing high-frequency ultrasound from an external power source. A series of ablations must be performed in order to treat a big volume of tumors, as a single ablation can only remove a small amount of tissue. To maximize therapeutic efficacy while minimizing adverse side effects such as skin burns, preoperative treatment planning is essential in determining the focal site and sonication duration for each ablation. Here, we introduce a machine learning-based approach for designing HIFU treatment plans, which makes use of a map of the material characteristics unique to a patient alongside an accurate thermal simulation. A numerical model was employed to solve the governing equations of HIFU process and to simulate the HIFU absorption mechanism, including ensuing heat transfer process and the temperature rise during the sonication period. To validate the accuracy of this numerical model, a series of tests was conducted using ex vivo bovine liver. The findings indicate that the developed models properly represent the considerable variances observed in tumor geometrical shapes and proficiently generate well-defined closed treated regions based on imaging data. The proposed strategy facilitated the formulation of high-quality treatment plans, with an average tissue over- or under-treatment rate of less than 0.06%. The efficacy of the numerical model in accurately predicting the heating process of HIFU, when combined with machine learning techniques, was validated through quantitative comparison with experimental data. The proposed approach in cooperation with HIFU simulation holds the potential to enhance presurgical HIFU plan.

Case report: Sequential treatment strategy for advanced basal cell carcinoma in Gorlin-Goltz syndrome: integration of vismodegib, radiotherapy, surgery, and high-intensity focused ultrasound.

Managing advanced basal cell carcinoma (BCC) in patients with Gorlin-Goltz syndrome presents unique clinical challenges due to the tumor's aggressive nature and potential for widespread metastasis. This case study details a sequential treatment regimen for a 68-year-old female patient with an extensive, inoperable BCC. Employing a multimodal approach that integrates radiotherapy, the Hedgehog pathway inhibitor vismodegib, and High-Intensity Focused Ultrasound (HIFU), we demonstrate the potential for nearly complete remission in a patient with advanced BCC. Initial treatment with radiotherapy and vismodegib reduced tumor size significantly, but the largest mass displayed resistance over time, signifying the need for innovative therapies. Subsequent HIFU treatment targeted individual lesions, showcasing a non-invasive method that provided precise treatment while mitigating systemic side effects. The case emphasizes the necessity of continual adaptation in treatment plans to address the development of resistance and underscores the importance of incorporating new technologies and targeted therapies for complex BCC cases. The successful outcome of this integrated strategy suggests a promising direction for future research and highlights the importance of multidisciplinary approaches that tailor treatment to individual patient needs, tumor characteristics, and evolving therapeutic landscapes.

Ultrasound-Guided High-Intensity Focused Ultrasound of Uterine Fibroids and Adenomyosis: An 11-Year Experience from a Single Center in Hong Kong.

Introduction: This study evaluated the efficacy and safety of ultrasound-guided high-intensity focused ultrasound (HIFU) in treating symptomatic uterine fibroids and adenomyosis. Methods: HIFU treatments performed in premenopausal women with symptomatic uterine fibroids and adenomyosis were analyzed retrospectively. Lesion volume reduction, change in symptoms of menstrual pain, and quality of life were examined. Major and minor complications, together with re-intervention rates, were evaluated. Results: Eighty-one HIFU treatments were performed in seventy-nine premenopausal women. The follow-up period was up to 95 months. A total of 65 women underwent treatment for uterine fibroids and 14 were treated for adenomyosis. For patients with uterine fibroids, the baseline fibroid volume median was 190.1 cm3 (18.5-1729.4 cm3). Fibroid volume was reduced by 50.1% (-26.2-97.8, p < 0.0001) at 6 months and 66.9% (-33.7-98.3, p < 0.0001) at 12 months after treatment. The modified Uterine Fibroid Symptom and Quality of Life (UFS-QOL) scores had decreased by 43.5% (0-62.5%, p < 0.0001) at 6 months and 50% (0-73%, p < 0.0001) at 12 months after treatment. In the adenomyosis arm, the median baseline uterine volume was 97.7 cm3 (43.7-367.4 m3). Uterine volume was reduced by 19.6% (range: 1.2-42.0, p = 0.28) at 6 months and 41.9% (18.9-69.2, p = 0.04) at 12 months after treatment. UFS-QOL scores were reduced by 38.1% (6-66.7%, p < 0.0001) at 6 months and 40% (0-70%, p < 0.0001) at 12s month after treatment. Fourteen (21.5%) patients with uterine fibroid and five (35.7%) patients with adenomyosis required subsequent interventions. Conclusions: HIFU provides symptomatic relief to most patients with uterine fibroids and adenomyosis. It is a promising uterus-sparing treatment for patients with these conditions.

Pilot Study on High-Intensity Focused Ultrasound (HIFU) for Basal Cell Carcinoma: Effectiveness and Safety.

Background: The rising incidence of Basal Cell Carcinoma (BCC), especially among individuals with significant sun exposure, underscores the need for effective and minimally invasive treatment alternatives. Traditional surgical approaches, while effective, often result in notable cosmetic and functional limitations, particularly for lesions located on the face. This study explores High-Intensity Focused Ultrasound (HIFU) as a promising, non-invasive treatment option that aims to overcome these challenges, potentially revolutionizing BCC treatment by offering a balance between efficacy and cosmetic outcomes. Methods: Our investigation enrolled 8 patients, presenting a total of 15 BCC lesions, treated with a 20 MHz HIFU device. The selection of treatment parameters was precise, utilizing probe depths from 0.8 mm to 2.3 mm and energy settings ranging from 0.7 to 1.3 Joules (J) per pulse, determined by the lesion's infiltration depth as assessed via pre-procedure ultrasonography. A key component of our methodology included dermatoscopic monitoring, which allowed for detailed observation of the lesions' response to treatment over time. Patient-reported outcomes and satisfaction levels were systematically recorded, providing insights into the comparative advantages of HIFU. Results: Initial responses after HIFU treatment included whitening and edema, indicative of successful lesion ablation. Early post-treatment observations revealed minimal discomfort and quick recovery, with crust formation resolving within two weeks for most lesions. Over a period of three to six months, patients reported significant improvement, with lesions becoming lighter and blending into the surrounding skin, demonstrating effective and aesthetically pleasing outcomes. Patient satisfaction surveys conducted six months post-treatment revealed high levels of satisfaction, with 75% of participants reporting very high satisfaction due to minimal scarring and the non-invasive nature of the procedure. No recurrences of BCC were noted, attesting to the efficacy of HIFU as a treatment option. Conclusions: The findings from this study confirm that based on dermoscopy analysis, HIFU is a highly effective and patient-preferred non-invasive treatment modality for Basal Cell Carcinoma. HIFU offers a promising alternative to traditional surgical and non-surgical treatments, reducing the cosmetic and functional repercussions associated with BCC management. Given its efficacy, safety, and favorable patient satisfaction scores, HIFU warrants further investigation and consideration for broader clinical application in the treatment of BCC, potentially setting a new standard in dermatologic oncology care. This work represents a pilot study that is the first to describe the use of HIFU in the treatment of BCC.

Prediction of high-intensity focused ultrasound (HIFU)-induced lesion size using the echo amplitude from the focus in tissue.

In the realm of high-intensity focused ultrasound (HIFU) therapy, the precise prediction of lesion size during treatment planning remains a challenge, primarily due to the difficulty in quantitatively assessing energy deposition at the target site and the acoustic properties of the tissue through which the ultrasound wave propagates. This study investigates the hypothesis that the echo amplitude originating from the focus is indicative of acoustic attenuation and is directly related to the resultant lesion size. Echoes from multi-layered tissues, specifically porcine tenderloin and bovine livers, with varying fat thickness from 0 mm to 35 mm were collected using a focused ultrasound (FUS) transducer operated at a low power output and short duration. Subsequent to HIFU treatment under clinical conditions, the resulting lesion areas in the ex vivo tissues were meticulously quantified. A novel treatment strategy that prioritizes treatment spots based on descending echo amplitudes was proposed and compared with the conventional raster scan approach. Our findings reveal a consistent trend of decreasing echo amplitudes and HIFU-induced lesion areas with the increasing fat thickness. For porcine tenderloin, the values decreased from 2541.7 ± 641.9 mV and 94.4 ± 17.9 mm2 to 385(342.5) mV and 24.9 ± 18.7 mm2, and for bovine liver, from 1406(1202.5) mV and 94.4 ± 17.9 mm2 to 502.1 ± 225.7 mV and 9.4 ± 6.3 mm2, respectively, as the fat thickness increases from 0 mm to 35 mm. Significant correlations were identified between preoperative echo amplitudes and the HIFU-induced lesion areas (R = 0.833 and 0.784 for the porcine tenderloin and bovine liver, respectively). These correlations underscore the potential for an accurate and dependable prediction of treatment outcomes. Employing the proposed treatment strategy, the ex vivo experiment yielded larger lesion areas in bovine liver at a penetration depth of 8 cm compared to the conventional approach (58.84 ± 17.16 mm2 vs. 44.28 ± 15.37 mm2, p < 0.05). The preoperative echo amplitude from the FUS transducer is shown to be a reflective measure of acoustic attenuation within the wave propagation window and is closely correlated with the induced lesion areas. The proposed treatment strategy demonstrated enhanced efficiency in ex vivo settings, affirming the feasibility and accuracy of predicting HIFU-induced lesion size based on echo amplitude.

The safety and efficacy of myomectomy in the treatment of recurrent uterine fibroids after HIFU.

OBJECTIVE: To evaluate the safety and efficacy of myomectomy for recurrent uterine fibroids (UFs) after high-intensity focused ultrasound (HIFU) ablation. METHODS: This was a retrospective study. Patients who underwent abdominal myomectomy (AM) and laparoscopic myomectomy (LM) from January 2018 to December 2021 at the Three Gorges Hospital of Chongqing University were included. Among them, 73 had undergone prior HIFU ablation (Group 1), while 120 had not undergone HIFU (Group 2). Outcome measures included operating time, estimated blood loss (EBL), blood transfusion, postoperative activity times (PAT), duration of hospital stay (DOHS), and complications. RESULTS: The operating time was 90.0 min (70.5, 115.0) for Group 1 and 110.0 min (81.5, 130.0) for Group 2 (P < 0.05). During all AM pathways, there were no significant differences observed between the two groups in EBL, blood transfusion, PAT, DOHS, and complications; however, operating time was shorter in Group 1. The operating time, EBL, blood transfusion, PAT, DOHS, and complications were similar in both groups during LM pathway. During the follow-up 40 (range: 24-53) months, the rate of relief, recurrence, and reintervention in Groups 1 and 2 was 78.1% versus 74.1%, 14.6% versus 16.4%, and 3.7% versus 2.6%, respectively (P > 0.05). CONCLUSION: Myomectomy is a safe and effective surgical method for treating recurrent UFs after HIFU. Myomectomy for treating recurrent UFs resulted in a shorter operative and hospital stay, reduced blood loss, faster postoperative recovery, and fewer complications, better symptom relief rates, and lower risk of recurrence or reintervention. These findings indicate that previous HIFU ablation does not worsen the outcomes of the subsequent myomectomy.

A Fast and Interactive Augmented Reality System for PET/CT-guided Intervention of Neuroblastoma.

Neuroblastoma is the most common type of extracranial solid tumor in children and can often result in death if not treated. High-intensity focused ultrasound (HIFU) is a non-invasive technique for treating tissue that is deep within the body. It avoids the use of ionizing radiation, avoiding long-term side-effects of these treatments. The goal of this project was to develop the rendering component of an augmented reality (AR) system with potential applications for image-guided HIFU treatment of neuroblastoma. Our project focuses on taking 3D models of neuroblastoma lesions obtained from PET/CT and displaying them in our AR system in near real-time for use by physicians. We used volume ray casting with raster graphics as our preferred rendering method, as it allows for the real-time editing of our 3D radiologic data. Some unique features of our AR system include intuitive hand gestures and virtual user interfaces that allow the user to interact with the rendered data and process PET/CT images for optimal visualization. We implemented the feature to set a custom transfer function, set custom intensity cutoff points, and region-of-interest extraction via cutting planes. In the future, we hope to incorporate this work as part of a complete system for focused ultrasound treatment by adding ultrasound simulation, visualization, and deformable registration.

The Effectiveness of High-Intensity Focused Ultrasound in Treating Nasal Obstruction Caused by Inferior Turbinate Hypertrophy: A Clinical Study.

Background Nasal obstruction due to inferior turbinate hypertrophy is a common medical complaint among ENT clinic patients, which can significantly affect the patient's quality of life, and some are compelled to use topical intranasal decongestants. Conservative management is the first line of treatment; however, surgical reduction of the inferior turbinate becomes necessary if the symptoms persist after three months of treatment. The optimal surgical technique is controversial. High-intensity focused ultrasound (HIFU) is a minimally invasive surgical option that targets tissue volume precisely and minimally impacts surrounding tissue. This study aimed to assess the effectiveness and safety of HIFU in treating patients suffering from nasal obstruction due to inferior turbinate hypertrophy. Methods This prospective study was conducted from February to December 2016. The study lasted over six months. Patients with a history of allergic and non-allergic rhinitis participated in this study. It included 43 patients who had been experiencing chronic nasal obstruction due to bilateral inferior turbinate hypertrophy and had not shown improvement after three months of medical treatment. The patients underwent Ultrasound Volumetric Tissue Reduction (UVTR) surgery using the D & A Ultrasurg device (Diamant Medical Equipment Ltd., Amman, Jordan) under local anesthesia. The effectiveness, safety, and tolerance of HIFU were assessed subjectively for six months using a well-designed questionnaire utilizing a visual analog scale (VAS) and nasal endoscopy after the surgery. Results The study included 43 patients, 22 male and 21 female, aged 13 to 65 years. The study found that 40 (93%) patients showed significant improvement in nasal obstruction within a month of the surgery. However, three (7%) patients continued to experience persistent nasal obstruction even after six months of follow-up. The procedure was well-tolerated, with low rates of complications after surgery and reasonable pain control. During the surgery, 20 (46.5%) patients reported mild pain described as a pressure-like sensation, and 10 out of 43 patients (23%) required paracetamol after the procedure. Four patients (9.3%) had mild bleeding, which was treated with an ultrasound nasal probe without nasal packing. All patients experienced crusting of the nasal cavity during the first week, but no crustation was observed after the first month. There were no reported cases of synechia among the patients. Conclusion This study confirms that HIFU treatment is a reliable and effective treatment for improving short-term nasal obstruction caused by inferior turbinate hypertrophy. The procedure is easily applied and well-tolerated in outpatient clinics.

Achieving NPVR ≥ 80% as technical success of high-intensity focused ultrasound ablation for uterine fibroids: a cohort study.

OBJECTIVE: To report the long-term re-intervention of patients with uterine fibroids after ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation and to analyse the influencing factors of re-intervention in patients in the NPVR ≥ 80% group. MATERIALS AND METHODS: Patients with a single uterine fibroid who underwent USgHIFU at our hospital from January 2012 to December 2019 were enrolled. The patients were divided into four groups according to different nonperfusion volume ratio (NPVR). Kaplan-Meier survival curve was used to analyse long-term re-intervention in different NPVR groups, and Cox regression was used to analyse the influencing factors of re-intervention in the NPVR ≥ 80% group. MAIN RESULTS: A total of 1,257 patients were enrolled, of whom 920 were successfully followed up. The median follow-up time was 88 months, and the median NPVR was 85.0%. The cumulative re-intervention rates at 1, 3, 5, 8 and 10 years after USgHIFU were 3.4%, 11.8%, 16.8%, 22.6% and 24.1%, respectively. The 10-year cumulative re-intervention rate was 37.3% in the NPVR < 70% group, 31.0% in the NPVR 70-79% group, 18.2% in the NPVR 80-89% group and 17.8% in the NPVR ≥ 90% group (P < 0.05). However, no difference was found between the group of NPVR 80-89% and the group of NPVR ≥ 90% (P = 0.499). Age of patients and signal intensity on T2-weighted imaging (T2WI) of tumours were found to be independent risk factors for long-term re-intervention in the NPVR ≥ 80% group. A younger age and greater signal intensity on T2W images corresponded to a greater risk of re-intervention. CONCLUSION: USgHIFU, an alternative treatment for uterine fibroids, has reliable long-term efficacy. NPVR ≥ 80% can be used as a sign of technical success, which can reduce re-intervention rates. However, an important step is to communicate with patients in combination with the age of patients and the signal intensity on T2WI of fibroids. TRIAL REGISTRATION: This retrospective study was approved by the ethics committee at our institution (Registration No. HF2023001; Date: 06/04/2023). The Chinese Clinical Trial Registry provided full approval for the study protocol (Registration No. CHiCTR2300074797; Date: 16/08/2023).

Suppressing HIFU interference in ultrasound images using 1D U-Net-based neural networks.

Objective.One big challenge with high-intensity focused ultrasound (HIFU) is that the intense acoustic interference generated by HIFU irradiation overwhelms the B-mode monitoring images, compromising monitoring effectiveness. This study aims to overcome this problem using a one-dimensional (1D) deep convolutional neural network.Approach. U-Net-based networks have been proven to be effective in image reconstruction and denoising, and the two-dimensional (2D) U-Net has already been investigated for suppressing HIFU interference in ultrasound monitoring images. In this study, we propose that the one-dimensional (1D) convolution in U-Net-based networks is more suitable for removing HIFU artifacts and can better recover the contaminated B-mode images compared to 2D convolution.Ex vivoandinvivoHIFU experiments were performed on a clinically equivalent ultrasound-guided HIFU platform to collect image data, and the 1D convolution in U-Net, Attention U-Net, U-Net++, and FUS-Net was applied to verify our proposal.Main results.All 1D U-Net-based networks were more effective in suppressing HIFU interference than their 2D counterparts, with over 30% improvement in terms of structural similarity (SSIM) to the uncontaminated B-mode images. Additionally, 1D U-Nets trained usingex vivodatasets demonstrated better generalization performance ininvivoexperiments.Significance.These findings indicate that the utilization of 1D convolution in U-Net-based networks offers great potential in addressing the challenges of monitoring in ultrasound-guided HIFU systems.

Development and validation of a radiomics model based on T2-weighted imaging for predicting the efficacy of high intensity focused ultrasound ablation in uterine fibroids.

Background: The heterogeneity of uterine fibroids in magnetic resonance imaging (MRI) is complex for a subjective visual evaluation, therefore it is difficult for an accurate prediction of the efficacy of high intensity focused ultrasound (HIFU) ablation in fibroids before the treatment. The purpose of this study was to set up a radiomics model based on MRI T2-weighted imaging (T2WI) for predicting the efficacy of HIFU ablation in uterine fibroids, and it would be used in preoperative screening of the fibroids for achieving high non-perfused volume ratio (NPVR). Methods: A total of 178 patients with uterine fibroids were consecutively enrolled and treated with ultrasound-guided HIFU under conscious sedation between February 2017 and December 2021. Among them, 96 patients with 108 uterine fibroids with high ablation efficacy (NPVR ≥80%, h_NPVR) and 82 patients with 92 fibroids with lower ablation efficacy (NPVR <80%, l_NPVR) were retrospectively analyzed. The transverse T2WI images of fibroids were selected, and the fibroids were delineated slice by slice using ITK-SNAP software. The radiomics analysis was performed to find the imaging biomarker for the construction of a predicting model for the evaluation of the ablation efficacy, including the feature extraction, feature selection and model construction. The prediction model was built by logistic regression and assessed by receiver operating characteristic (ROC) curve, and the prediction efficiency of the two models was compared by Delong test. The ratio of the training set to the testing set was 8:2. Results: The logistic regression model showed that the mean area under the curve (AUC) of the training set was 0.817 [95% confidence interval (CI): 0.755-0.882], and the testing set was 0.805 (95% CI: 0.670-0.941), respectively, which indicated a strong classification ability. The Delong test showed that there was no significant difference in the area under the ROC curve between the training set and testing set (P>0.05). Conclusions: The radiomics model based on T2WI is feasible and effective for predicting the efficacy of HIFU ablation in treatment of uterine fibroids.

Clinical value of high-intensity focused ultrasound in fetal reduction.

Complex twin reduction surgery is a common but challenging procedure that aims to reduce the risks and complications of multiple pregnancies. The search for safer and more effective methods has led to the development of high-intensity focused ultrasound (HIFU) technology in the field of fetal reduction. This technology utilizes high-energy sound waves to focus precisely on specific areas, achieving non-invasive therapeutic effects. This paper discusses the principles and features of HIFU technology, as well as its application in complex twin reduction surgery. The paper aims to elucidate the important role of this technology in improving surgical outcomes and reducing risks, explore the current limitations of the modality, and propose directions for future development. Through these investigations, it is hoped to improve overall understanding of HIFU, and thereby promote the application of this technology in the field of fetal reduction.

Factors influencing magnetic resonance imaging changes associated with pelvic bone injury after high-intensity focused ultrasound ablation of uterine fibroids: a retrospective case-control study.

Background: The application of high-intensity focused ultrasound (HIFU) in the treatment of uterine fibroids is becoming increasingly widespread, and postoperative collateral thermal damage to adjacent tissue has become a prominent subject of discussion. However, there is limited research related to bone injury. Therefore, the aim of this study was to investigate the potential factors influencing unintentional pelvic bone injury after HIFU ablation of uterine fibroids with magnetic resonance imaging (MRI). Methods: A total of 635 patients with fibroids treated with HIFU in the First Affiliated Hospital of Chongqing Medical University were enrolled. All patients underwent contrast-enhanced MRI (CE-MRI) pre- and post-HIFU. Based on the post-treatment MRI, the patients were divided into two groups: pelvic bone injury group and non-injury group, while the specific site of pelvic bone injury of each patient was recorded. The univariate and multivariate analyses were used to assess the correlations between the factors of fibroid features and treatment parameters and pelvic bone injury, and to further analyze the factors influencing the site of injury. Results: Signal changes in the pelvis were observed on CE-MRI in 51% (324/635) of patients after HIFU. Among them, 269 (42.4%) patients developed sacral injuries and 135 (21.3%) had pubic bone injuries. Multivariate analyses showed that patients with higher age [P=0.003; odds ratio (OR), 1.692; 95% confidence interval (CI): 1.191-2.404], large anterior side-to-skin distance of fibroid (P<0.001; OR, 2.297; 95% CI: 1.567-3.365), posterior wall fibroid (P=0.006; OR, 1.897; 95% CI: 1.204-2.989), hyperintensity on T2-weighted imaging (T2WI, P=0.003; OR, 2.125; 95% CI: 1.283-3.518), and large therapeutic dose (TD, P<0.001; OR, 3.007; 95% CI: 2.093-4.319) were at higher risk of postoperative pelvic bone injury. Further analysis of the factors influencing the site of the pelvic bone injury showed that some of the fibroid features and treatment parameters were associated with it. Moreover, some postoperative pain-related adverse events were associated with the pelvic bone injury. Conclusions: Post-HIFU treatment, patients may experience pelvic injuries to the sacrum, pubis, or a combination of both, and some of them experienced adverse events. Some fibroid features and treatment parameters are associated with the injury. Taking its influencing factors into full consideration preoperatively, slowing down treatment, and prolonging intraoperative cooling phase can help optimize treatment decisions for HIFU.

Non-invasive Body Contouring Technologies: An Updated Narrative Review.

INTRODUCTION: Nowadays, a lot of body contouring devices and methods are introduced all over the world. The object of the present narrative review was to update and classify existing evidence on these methods and devices. METHODS: We searched databases including PubMed, Cochrane, and Google Scholar for 11 essential keywords, including cryolipolysis, high-intensity focused ultrasound (HIFU), shock wave, low-level laser therapy (LLLT), radiofrequency (RF), capacitive resistive electrical transfer (TECAR), high-intensity focused electromagnetic (HIFEM), electromyostimulation (EMS), carboxytherapy, mesotherapy, and acupuncture and their abbreviations, in addition to obesity, overweight, cellulite, subcutaneous fat, and body contouring. RESULTS: Totally 193 references were used in 11 main topics. CONCLUSION: In order to help physicians with finding the best evidence in different methods, the data were summarised in 11 topics. Furthermore, FDA-approved devices, side effects and common protocols were described in each section. LEVEL OF EVIDENCE I: This journal requires that authors 39 assign a level of evidence to each article. For a full 40 description of these Evidence-Based Medicine ratings, 41 please refer to the Table of Contents or the online 42 Instructions to Authors www.springer.com/00266 .