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.

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.

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.

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.

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).

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.

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 .

Efficacy and safety of different thermal ablative therapies for desmoid-type fibromatosis: a systematic review and meta-analysis.

Background: Desmoid-type fibromatosis (DF) is a locally aggressive tumor characterized by peripheral infiltration of neoplastic cells and remote metastasis disability. This systematic review examined the efficacy and safety of thermal ablative therapy for DF tumors. Methods: A literature search was conducted using PubMed, Web of Science, Cochrane Library, and Embase from January 1, 2000, to November 12, 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was used to guide literature selection. The inclusion criteria were the following: (I) the patients were diagnosed with aggressive fibromatosis pathologically, (II) the patients were treated by thermal ablations, and (III) a focus on treatment efficacy and safety. Meanwhile, the exclusion criteria were the following: (I) cohorts of patients with hypertrophic scar, Gardner fibroma, or nodular fasciitis; (II) conference abstracts, reviews, case reports, letters to editors, comments, or editorials; (III) number of patients <5; (IV) in vitro or animal experiments; and (V) non-English language articles. The inverse variance method with a random effects model was used to obtain the pooled data. Subgroup analyses were performed to identify treatment factors. Egger test was conducted to assess the risk of publication bias. Results: After literature selection, 694 DF tumors were identified in 23 studies. In terms of modality, 13 studies used cryoablation, 9 studies used high-intensity focused ultrasound (HIFU), and 1 study used microwave ablation (MWA). The pooled symptom relief rate was 90% [95% confidence interval (CI): 80-97%], with that for HIFU being 100% (95% CI: 85-100%), that for cryoablation being 87% (95% CI: 74-97%), and that MWA being 89% (95% CI). The pooled major complication rate was 3% (95% CI: 1-7%), and that for each modality was as follows: HIFU =2% (95% CI: 0-6%), cryoablation =4% (95% CI: 1-8%), MWA =11%, ultrasound =6% (95% CI: 1-13%), computed tomography (CT) =2% (95% CI: 0-7%), and magnetic resonance imaging (MRI) =3% (95% CI: 0-14%). The pooled nonperfused volume rate (NPVR) was 76% (95% CI: 71-81%), and that for each modality was as follows: HIFU =77% (95% CI: 71-85%), cryoablation =74% (95% CI: 69-79%), ultrasound =75% (95% CI: 67-83%), CT =76% (95% CI: 67-87%), and MRI =78% (95% CI: 70-87%). The pooled local control rate was 88% (95% CI: 79-94%) and that for each modality was as follows: HIFU =99% (95% CI: 96-100%), cryoablation =80% (95% CI: 68-90%), and MWA =78%. The differences in major complication rate (P=0.77) and NPVR between imaging-guided modalities (P=0.40) were not significant, nor were the differences in symptom relief rate (P=0.32) and major complication rate (P=0.61) between ablative techniques; however, the differences in local control rate (P=0.01) were significant between ablative techniques. Conclusions: Imaging-guided thermal ablative therapies contribute to symptom relief with a duration of more than 6 months and a low major complication rate of DF tumors.

Pregnancy outcomes of adenomyotic patients with primary infertility after high-intensity focused ultrasound treatment.

OBJECTIVE: To evaluate the therapeutic effect of high-intensity focused ultrasound (HIFU) treatment for adenomyotic patients with primary infertility and to explore the factors that affect the pregnancy outcomes. MATERIALS AND METHODS: Twenty-seven adenomyotic patients with primary infertility who underwent HIFU at HUNAN Provincial Maternal and Child Health Care Hospital, China, between July 2018 and December 2022 were retrospectively reviewed. We evaluated the pregnancy outcomes and analyzed the factors that may affect pregnancy outcomes including time to conception, pregnancy approach, gestational age, delivery mode, neonatal outcomes, and complications during pregnancy and delivery. RESULTS: Among the 27 adenomyotic patients with primary infertility, 10 patients had a total of 11 pregnancies after HIFU treatment. Of these, eight (72%) cases were natural pregnancies and three (23%) were in vitro fertilization (IVF) pregnancies. The median time to conception was 10 (range 4-25) months. There were eight (72%) successful deliveries. The rate of full-term deliveries was 90%. Of the eight live births, four (50%) were born vaginally and four (50%) by cesarean section. No severe complications occurred. The mean birth weight of newborns was 3.1 (range: 2.3-3.9) kg; all newborns developed well without complications during postpartum and breastfeeding. CONCLUSIONS: HIFU treatment for adenomyosis could improve fertility of patients with primary infertility. HIFU is a promising therapeutic approach for patients with adenomyosis and infertility who wish to achieve pregnancy and have live birth deliveries.

Artificial intelligence-assisted ultrasound-guided focused ultrasound therapy: a feasibility study.

OBJECTIVES: Focused ultrasound (FUS) therapy has emerged as a promising noninvasive solution for tumor ablation. Accurate monitoring and guidance of ultrasound energy is crucial for effective FUS treatment. Although ultrasound (US) imaging is a well-suited modality for FUS monitoring, US-guided FUS (USgFUS) faces challenges in achieving precise monitoring, leading to unpredictable ablation shapes and a lack of quantitative monitoring. The demand for precise FUS monitoring heightens when complete tumor ablation involves controlling multiple sonication procedures. METHODS: To address these challenges, we propose an artificial intelligence (AI)-assisted USgFUS framework, incorporating an AI segmentation model with B-mode ultrasound imaging. This method labels the ablated regions distinguished by the hyperechogenicity effect, potentially bolstering FUS guidance. We evaluated our proposed method using the Swin-Unet AI architecture, conducting experiments with a USgFUS setup on chicken breast tissue. RESULTS: Our results showed a 93% accuracy in identifying ablated areas marked by the hyperechogenicity effect in B-mode imaging. CONCLUSION: Our findings suggest that AI-assisted ultrasound monitoring can significantly improve the precision and control of FUS treatments, suggesting a crucial advancement toward the development of more effective FUS treatment strategies.

Feasibility and efficacy of ultrasound-guided high-intensity focused ultrasound of breast fibroadenoma.

OBJECTIVE: This nonrandomized prospective clinical trial aimed to assess the efficacy, safety and follow-up outcomes of ultrasound-guided high-intensity focused ultrasound (USgHIFU) surgery in patients with breast fibroadenoma. METHODS: With the approval of the institutional ethics committee and written informed consent, a total of 113 patients diagnosed with breast fibroadenoma by core-needle biopsy in our hospital were recruited. USgHIFU surgery was performed under local anesthesia. Contrast-enhanced ultrasound (CEUS) or contrast-enhanced MRI (CEMRI) was performed to evaluate the nonperfused volume (NPV). The patients were followed up with physical examination and ultrasound imaging. RESULTS: The clinical outcome of 85 patients with 147 fibroadenomas with a follow-up time of more than 3 months was analyzed in this study. Fifty-two patients had one lesion, twenty-one patients had two lesions and twelve patients had more than two lesions. During USgHIFU, the median localization time for all fibroadenomas was 3 (interquartile range: 1, 5) min, and the median treatment time was 9 (interquartile range: 5, 15) min. Under local anesthesia, all the patients tolerated the treatment well. No serious epidermal burns were observed in any of the patients. Based on CEUS or CEMRI imaging evaluation, the median NPV ratio was 100% (interquartile range: 79.2%, 116.8%). The VRR were 26.77 ± 50.05%, 50.22 ± 42.01% and 72.74 ± 35.39% at 3-6 months, 6-12 months and >12 months, respectively, which showed significant statistical difference (p < .001). CONCLUSION: Ultrasound-guided HIFU surgery is an effective and safe noninvasive alternative technique for the treatment of breast fibroadenoma.

Improved source localization in passive acoustic mapping using delay-multiply-and-sum beamforming with virtually augmented aperture.

High-intensity focused ultrasound (HIFU) is a promising non-invasive treatment method whose applications include tissue ablation, hemostasis, thrombolysis and blood-brain barrier opening etc. Its therapeutic effects come from the thermal necrosis and the mechanical destruction associated with acoustic cavitation. Passive acoustic mapping (PAM) is capable of simultaneous monitoring of HIFU-induced cavitation events using only receive beamforming. Nonetheless, conventional time exposure acoustics (TEA) algorithm has poor spatial resolution and suffers from the X-shaped artifacts. These factors lead to difficulties in precise localization of cavitation source. In this study, we proposed a novel adaptive PAM method which combines Delay-Multiply-and-Sum (DMAS) beamforming with virtual augmented aperture (VA) to overcome the problem. In DMAS-VA beamforming, the magnitude of each channel waveform is scaled by p-th root while the phase is multiplied by L. The p and L correspond respectively to the degree of signal coherence in DMAS beamforming and the augmentation factor of aperture size. After channel sum, p-th power is applied to restore the dimensionality of source strength and then the PAM image is reconstructed by accumulating the signal power over the observation time. Based on simulation and experimental results, the proposed DMAS-VA has better image resolution and image contrast compared with the conventional TEA. Moreover, since the VA method may introduce grating lobes into PAM because of the virtually augmented pitch size, DMAS coherent factor (DCF) is further developed to alleviate these image artifacts. Results indicate that, with DCF weighting, the PAM image of DMAS-VA beamforming could be constructed without detectable image artifacts from grating lobes and false main lobes.

High-intensity focused ultrasound for benign thyroid nodules: Systemic review and meta-analysis.

BACKGROUND: High-intensity focused ultrasound (HIFU) is a less invasive option offered for the treatment of large, compressive, benign thyroid nodules. METHODS: Observational studies of more than five participants using HIFU in the management of benign thyroid nodules from 2000 to 2021 were identified using predefined inclusion criteria. The primary outcome was an estimate of the effectiveness of HIFU. RESULTS: Out of 158 studies reviewed, 8 articles were included with 297 patients and 300 nodules. HIFU significantly reduced nodule volume from 1 to 24 months following therapy (weighted mean difference [WMD], 47.68, 95 % confidence interval [CI], 34.13-59.66, p < 0.0001) and achieved favorable success rates (risk ratio [RR], 1.49, 95 % CI, 1.15-1.84, p < 0.001) for 50 % volume reduction. CONCLUSIONS: HIFU appears to be a feasible, safe, and effective treatment modality for patients with benign thyroid nodules. Future research, including randomized controlled trials, is needed to determine therapy optimization, and patient selection to identify the potential role of this new therapy.

Prostate cancer outcomes following whole-gland and focal high-intensity focused ultrasound.

OBJECTIVE: To report the 5-year failure-free survival (FFS) following high-intensity focused ultrasound (HIFU). PATIENTS AND METHODS: This observational cohort study used linked National Cancer Registry data, radiotherapy data, administrative hospital data and mortality records of 1381 men treated with HIFU for clinically localised prostate cancer in England. The primary outcome, FFS, was defined as freedom from local salvage treatment and cancer-specific mortality. Secondary outcomes were freedom from repeat HIFU, prostate cancer-specific survival (CSS) and overall survival (OS). Cox regression was used to determine whether baseline characteristics, including age, treatment year, T stage and International Society of Urological Pathology (ISUP) Grade Group were associated with FFS. RESULTS: The median (interquartile range [IQR]) follow-up was 37 (20-62) months. The median (IQR) age was 65 (59-70) years and 81% had an ISUP Grade Group of 1-2. The FFS was 96.5% (95% confidence interval [CI] 95.4%-97.4%) at 1 year, 86.0% (95% CI 83.7%-87.9%) at 3 years and 77.5% (95% CI 74.4%-80.3%) at 5 years. The 5-year FFS for ISUP Grade Groups 1-5 was 82.9%, 76.6%, 72.2%, 52.3% and 30.8%, respectively (P < 0.001). Freedom from repeat HIFU was 79.1% (95% CI 75.7%-82.1%), CSS was 98.8% (95% CI 97.7%-99.4%) and OS was 95.9% (95% CI 94.2%-97.1%) at 5 years. CONCLUSION: Four in five men were free from local salvage treatment at 5 years but treatment failure varied significantly according to ISUP Grade Group. Patients should be appropriately informed with respect to salvage radical treatment following HIFU.

Recanalize ureteral stents with focused ultrasound.

BACKGROUND: Maintaining ureteral patency is imperative to preventing renal injury and systemic infection. Ureteral stents are small conduits connecting the kidney and the bladder. They have been widely used to treat ureteral obstructions and ureteral leaks. The most problematic and frequent stent-associated complication is stent encrustation. This occurs when mineral crystals (e.g. calcium, oxalate, phosphorus, struvite) are deposited onto the surface and internal lumen of the stent. Encrustation can lead to the obstruction of a stent and increases risk of systemic infection. As a result, ureteral stents need to be replaced typically every 2-3 months. PURPOSE: In this study, we present a non-invasive, high-intensity focused ultrasound (HIFU)-based technique to recanalize obstructed stents. By taking advantage of the mechanical force produced by a HIFU beam, including acoustic radiation force, acoustic streaming, and cavitation, HIFU can break up encrustations, clearing the stent of obstruction. METHODS: The ureteral stents for this study were obtained from patients undergoing ureteral stent removal. Under the guidance of ultrasound imaging, the encrustation in the stents were located, and then targeted by HIFU at frequencies of 0.25 and 1 MHz. The duty cycle of HIFU was 10%, and the HIFU burst repetition rate was 1 Hz, while the HIFU amplitude was varied to find the threshold pressure that would displace encrustations. The treatment duration was limited at 2 min (or 120 shots from HIFU). The treatments were carried out in two different orientations (parallel and perpendicular) of the ureteral stent with respect to the HIFU beam. For each setting, five treatments were conducted for a maximum duration of 2 min. During the entire treatment, an ultrasound imaging system was used to monitor the movement of encrustations inside the stent. The peak negative HIFU pressures needed to move the encrustations inside the stent was recorded for quantitative analysis. RESULTS: Our results demonstrated that at both 0.25 and 1 MHz ultrasound frequencies, obstructed stents could be recanalized. At 0.25 MHz, the needed average peak negative pressure was 0.52 MPa in parallel orientation and 0.42 MPa in perpendicular orientation. At 1 MHz, the needed average peak negative pressure was 1.10 MPa in parallel orientation and 1.15 MPa in perpendicular orientation CONCLUSIONS: This first in-vitro study has demonstrated the feasibility of non-invasive HIFU to recanalize ureteral stents. This technology has a potential to reduce the need for ureteral stent exchange.

High Intensity Focused Ultrasound Ablation for Juvenile Cystic Adenomyosis: Two Case Reports and Literature Review.

Cystic adenomyosis is a rare type of uterine adenomyosis, mainly seen in young women, which is often characterized by severe dysmenorrhea. The quality of life and reproductive function of young women could be affected by misdiagnosis and delayed treatment. At present, there are no universal guidelines and consensus. We report two cases of patients with cystic adenomyosis in juveniles treated with high-intensity focused ultrasound (HIFU) ablation. In the first case, magnetic resonance imaging (MRI) indicated a cystic mass of 2.0 cm × 3.1 cm × 2.4 cm in the uterus. After she underwent HIFU treatment, her pelvic MRI showed a mass of 1.1 × 2.4 cm in size, and her dysmenorrhea symptoms gradually disappeared. In the second case, a pelvic MRI indicated a 5.1 cm × 3.3 cm × 4.7 cm cystic mass in the uterus. After she underwent HIFU and combined four consecutive cycles of GnRH-a treatment, the lesion shrunk 1.2 cm ×1.4 cm × 1.6 cm, without dysmenorrhea. Simultaneously, the report reviewed 14 cases of juvenile cystic adenomyosis over the last ten years. HIFU or HIFU-combined drugs were safe and effective in treating juvenile cystic adenomyosis, but multicenter and prospective studies may be necessary to validate this in the future.