A costing and health-related quality of life study of high intensity focused ultrasound in primary treatment of localized low or intermediate risk prostate cancer in Ontario.

INTRODUCTION: Prostate cancer is the third leading cause of death from cancer among Canadian men. High intensity focused ultrasound (HIFU) is a novel approach for primary treatment of localized prostate cancer. Little is known, however, about its costs. We aimed to collect the direct costs and health-related quality of life (HRQoL) data of HIFU in primary treatment of localized low and intermediate risk prostate cancer in Ontario. MATERIALS AND METHODS: We collected direct costs and HRQoL data of 20 patients with localized low or intermediate risk prostate cancer who received whole-gland HIFU at a privately owned clinic in Ontario. We compared the direct costs of HIFU, open radical prostatectomy (ORP), robot assisted radical prostatectomy (RARP), and external beam radiation therapy (RT) in primary treatment of localized low and intermediate risk prostate cancer. RESULTS: The average direct costs of HIFU, ORP, RARP, and RT per case in 2023 are $14,886.78, $14,192.26, $21,794.55, and $17,377.51, respectively. The median and interquartile range (IQR) of the study participants' age and HRQoL data prior to the HIFU procedure were 64.5 (11.25) years, 94.5 (8.65), 38.5 (4), 6.0 (4.46), and 22.5 (8.32), respectively. CONCLUSION: Our healthcare payer's perspective costing study revealed median direct costs per case of HIFU and favorable HRQoL outcomes compared to other treatment options for primary treatment of localized low and intermediate risk prostate cancer in Ontario. A health economic model is warranted to analyze the cost-effectiveness of HIFU compared to other treatment options in primary treatment of localized low and intermediate risk prostate cancer.

Focused ultrasound for the treatment of facet joint pain: a systematic review.

OBJECTIVE: Chronic low-back pain (LBP) is a leading cause of disability worldwide, and traditional pharmacotherapy fails to provide relief for many individuals with this condition. An estimated 15% of chronic LBP cases can be attributed to the facet joint. High-intensity focused ultrasound (HIFU) is a recent technology that enables noninvasive thermal ablation of tissue and has shown efficacy in treating tumors, neuropathic pain, and painful bone metastases. In this systematic review, the authors summarize the literature on lumbar facet joint-mediated pain treated with HIFU and report the effectiveness of HIFU on pain outcomes. METHODS: All full-text English-language articles describing the use of focused ultrasound for facet joint pain were screened using the PubMed/MEDLINE, Embase, Cochrane Library, Scopus, and Web of Science databases. Clinical studies were assessed for bias using the methodological index for nonrandomized studies. RESULTS: Eleven studies (6 preclinical and 5 clinical) reporting on 50 patients were included. Eight of these studies (73%) used MR-guided focused ultrasound ablation and 3 used fluoroscopy. The medial branch nerve and posterior facet joint capsule were the most common targets for focused ablation. Although the energy used ranged from 300 to 2000 J, clinical studies predominantly operated in the range of 1000 to 1500 J. Pain reduction was seen in all clinical studies, with multiple-point reductions from average baseline pain scores in 6-12 months. No study reported any adverse events or complications. CONCLUSIONS: HIFU can be effective in treating chronic low-back pain arising from the facet joint. Further clinical studies should explore the long-term effects of HIFU and monitor changes in pain reduction over time.

Sonographic features of uterine fibroids that predict the ablation rate and efficacy of high-intensity focused ultrasound.

Objective: This study aimed to identify the sonographic indicators that predict the ablation rate and efficiency of uterine fibroids during high-intensity focused ultrasound (HIFU) treatment. Methods: In this retrospective study, we analyzed the clinical data of patients with uterine fibroids who underwent HIFU treatment at Fujian Provincial Hospital between April 2019 and April 2022. Routine abdominal ultrasound examinations were performed to observe potential indicators before the HIFU treatment. After the treatment, enhanced magnetic resonance imaging (MRI) examination was performed within 2 weeks. The fibroid and non-perfused volumes (NPV) were determined, and the ablation rate and energy efficiency factor (EEF) were calculated. Results: A total of 75 patients (124 uterine fibroids) were included in this study. Uterine fibroids with a larger volume, high echogenicity, elliptical/diffuse leaf shape, and a posterior attenuation band had a higher HIFU ablation rate (p<0.05). Uterine fibroids with a larger volume and high echogenicity and without necrotic areas had a lower EEF (p<0.05). Multiple comparisons between fibroid types revealed statistically significant differences in EEF between subserosal and submucosal fibroids (p < 0.05) and between subserosal and mixed-type fibroids (p < 0.05). However, no statistically significant difference was observed between mixed-type and submucosal fibroids. The HIFU ablation rate and EEF showed no significant differences based on location within the wall and blood flow within the fibroids. Conclusion: Sonographic features of uterine fibroids can predict the rate and efficiency of HIFU ablation, providing useful guidance in selecting appropriate treatment for patients.

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.

Therapeutic ultrasound transducer technology and monitoring techniques: a review with clinical examples.

The exponential growth of therapeutic ultrasound applications demonstrates the power of the technology to leverage the combinations of transducer technology and treatment monitoring techniques to effectively control the preferred bioeffect to elicit the desired clinical effect.Objective: This review provides an overview of the most commonly used bioeffects in therapeutic ultrasound and describes existing transducer technologies and monitoring techniques to ensure treatment safety and efficacy.Methods and materials: Literature reviews were conducted to identify key choices that essential in terms of transducer design, treatment parameters and procedure monitoring for therapeutic ultrasound applications. Effective combinations of these options are illustrated through descriptions of several clinical indications, including uterine fibroids, prostate disease, liver cancer, and brain cancer, that have been successful in leveraging therapeutic ultrasound to provide effective patient treatments.Results: Despite technological constraints, there are multiple ways to achieve a desired bioeffect with therapeutic ultrasound in a target tissue. Visualizations of the interplay of monitoring modality, bioeffect, and applied acoustic parameters are presented that demonstrate the interconnectedness of the field of therapeutic ultrasound. While the clinical indications explored in this review are at different points in the clinical evaluation path, based on the ever expanding research being conducted in preclinical realms, it is clear that additional clinical applications of therapeutic ultrasound that utilize a myriad of bioeffects will continue to grow and improve in the coming years.Conclusions: Therapeutic ultrasound will continue to improve in the next decades as the combination of transducer technology and treatment monitoring techniques will continue to evolve and be translated in clinical settings, leading to more personalized and efficient therapeutic ultrasound mediated therapies.

Histological characterization of HIFU lesions.

Background: High intensity focused ultrasound (HIFU) can destroy tissue by thermal ablation which may be accompanied by acoustic cavitation and/or tissue water boiling, but the biological and histological effects of these treatments have not been fully documented. Here, detailed histological analysis over time using well characterized HIFU exposures in in vivo rat livers is described.Methods: Exposures used invoked either (i) thermal, with acoustic cavitation and/or tissue water boiling or (ii) predominantly thermal damage. Cavitation activity was detected using both active and passive methods. Histological assessment involved hematoxylin and eosin (H&E), picrosirius red and immunohistochemical staining.Results: Distinct concentric damage regions were identified after HIFU exposures. The outermost ring showed a red H&E-stained rim that was characterized by hemorrhage. The adjacent inner band appeared white due to increased extracellular spaces. The morphology of the next zone depended on the exposure. Where there was no tissue acoustic cavitation/water boiling, this was the lesion center, in which heat-fixed cells were seen. Where acoustic cavitation/boiling occurred, a centermost zone with irregular holes up to several hundred microns across was seen. Cleaved caspase-3 and Hsp70 staining in the periphery of both types of HIFU exposures was seen within the outermost ring of hemorrhage, where an inflammatory response was also observed. By day 7, a distinct acellular region in the center of the HIFU lesions had been created.Conclusions: These results identify the morphological effects and elucidate the similarities and differences of HIFU-induced thermal lesions in the presence or absence of acoustic cavitation/tissue water boiling.

Analysis of factors affecting pregnancy outcomes in patients with adenomyosis after high intensity focused ultrasound ablation: a retrospective study.

OBJECTIVES: To investigate all pregnancies and analyze the factors influencing pregnancy outcomes in patients with adenomyosis after high intensity focused ultrasound (HIFU). MATERIALS AND METHODS: A total of 231 patients with adenomyosis who completed HIFU and wished to conceive were enrolled. The symptom improvement and information of pregnancy were recorded during the follow-up period. Factors influencing pregnancy outcomes were analyzed using multivariate regression analysis and survival analysis. RESULTS: After HIFU, 100 of 231 (43.3%) patients became pregnant within 96 months, including 77 (77/194, 39.7%) in natural and 23 (23/37, 62.2%) in vitro fertilization and embryo transfer (IVF-ET) pregnancies following gonadotropin-releasing hormone agonist (GnRHa). Among the 108 (46.8%, 108/231) infertile patients (defined as the failure to achieve pregnancy after 12 months of regular unprotected sexual intercourse, 40 primary infertility and 68 secondary infertility), 31 (28.7%) became pregnant. At the end of the follow-up, 70 successfully delivered 71 healthy babies. No uterine rupture occurred during pregnancy and delivery. Patients with pelvic adhesion and infertility history had a lower pregnancy chance than that of patients without pelvic adhesion and infertility history (OR < 1, p < 0.05). Patients with small adenomyotic lesion volume had a greater pregnancy chance than that of patients with large lesion volume (OR < 1, p < 0.05). IVF-ET following GnRHa had a better pregnancy chance (p < 0.05). CONCLUSIONS: HIFU seems to have a beneficial effect on fertility of patients with adenomyosis. Pelvic adhesion, infertility history, and large adenomyotic lesion volume have adverse effects on pregnancy, but IVF-ET following GnRHa after HIFU could increase the pregnancy chance.

Five-year follow-up after a single US-guided high intensity focused ultrasound treatment of breast fibroadenoma.

The aim of this study was to evaluate the long-term efficacy of a single ultrasound-guided high-intensity focused ultrasound (US-HIFU) treatment in patients with breast fibroadenoma (FA) in terms of volume and pain reduction as well as palpation findings. From december 2013 until november 2014 27 women with a symptomatic FA were treated in one HIFU-session. Follow-up visits were performed after 7 days, 6 months and 1, 2, 3 and 5 years with clinical examination and ultrasound. One year after the procedure, a core needle biopsy of the residual lesion was offered. There was a significant volume reduction 6 months after HIFU from 1083.10 to 347.13 mm3 (p < 0.0001) with a mean volume reduction ratio (VRR) of 61.63%. Thereafter the FAs showed a further, but no longer significant decrease in size. One patient with an initial incomplete ablation and histologically confirmed persistent vital cells after 1 year showed a strong regrowth after 3 years. Excluding this patient from analysis, the mean VRR at months 12, 24, 36, and 60 was 86.44%, 94.44%, 94.90%, and 97.85%, respectively. Before HIFU, 59.26% of the patients had pain (22.33/100 VAS) which decreased to 6.56/100 after 12 months and remained reduced over the 5 year follow up period. A decrease in palpability from 85.19 to 7.69% was observed within 24 months. A single HIFU intervention let to a substantial reduction in size, pain, and palpability with its most potential effect during the first 12 months. Subsequently, the observed effect remained stable over a 5 year follow up period. Incomplete initial treatment was associated with the risk of regrowth.

Integrating High-intensity Focused Ultrasound with Chemotherapy for the Treatment of Invasive Hydatidiform Mole in Reproductive-age Women.

Invasive hydatidiform mole, a form of gestational trophoblastic neoplasm in reproductive-age women, poses a significant threat to life due to its associated signs and symptoms. This case report details the management of a 24-year-old Chinese woman with no prior pregnancy history, who presented at our hospital 23 days postcurettage, experiencing persistent vaginal bleeding for 3 days. While two rounds of chemotherapy effectively reduced human chorionic gonadotropin levels, a subsequent magnetic resonance imaging (MRI) revealed suspicious growth lesions in the uterus. High-intensity focused ultrasound (HIFU) treatment was administered under ultrasound guidance, resulting in notable grayscale changes to optimize the efficacy of chemotherapy and restrict lesion progression. Subsequent ultrasound and MRI assessments during follow-up demonstrated a transparent texture in the muscle layer at the lesion site. This case suggests that the combination of chemotherapy and HIFU, guided by ultrasound, may represent a promising therapeutic approach for managing invasive hydatidiform mole.

A Systematic Review and Single-Arm Meta-Analysis on the Efficacy of High-Intensity, Focused Ultrasound for Benign Prostatic Hyperplasia Treatment: A Forgotten Option?

Benign prostatic hyperplasia (BPH) is a non-cancerous enlargement of prostate tissue, commonly affecting older men. This condition leads to lower urinary tract symptoms (LUTS), which significantly affect the quality of life. Over time, extensive research has been conducted regarding BPH treatment, exploring various treatment options. High-intensity focused ultrasound (HIFU) is a non-invasive treatment modality that has shown promise in initial studies. However, evidence regarding its long-term efficacy and safety remains inconclusive. This study evaluates HIFU's safety and efficacy for BPH treatment, identifying gaps for future research. The study conducted comprehensive searches across the PubMed, Google Scholar, Cochrane Central, and ClinicalTrials.gov databases, covering English-language articles from 1994 to 2023. Inclusion criteria focused on peer-reviewed studies, with more than 10 patients utilizing ultrasound image-guided HIFU for BPH while excluding other HIFU modalities lacking ultrasound image guidance. Data extraction targeted primary outcomes (peak flow rate, International Prostate Symptom Score (IPSS), postvoid residual volume) and secondary outcomes (treatment time, follow-up duration). Statistical analysis utilized a random effects model with heterogeneity assessed by I² statistics and the Q test, alongside subgroup analysis based on study design. The risk of bias assessment employed the Cochrane Collaboration tool for randomized controlled trials and the methodological index for nonrandomized studies. Among 560 identified articles, 12 studies with 522 patients met the inclusion criteria. Primary outcomes showed improvements in Qmax (1 month: 2.50 ml/s, 12 months: 6.22 ml/s) and IPSS (1 month: -9.37 points, 12 months: -11.60 points). Reported complications included transient hematuria, hematospermia, and urinary retention. HIFU presents significant clinical improvements in treating BPH, albeit with slow progression attributed to specific techniques and the ablative approach. Manageable complication profiles are observed, yet study design flaws hinder a comprehensive evaluation of HIFU efficacy. The authors suggest areas for clinical optimization, emphasizing the necessity of further research.

Weighted ultrasound entropy imaging for HIFU ablation monitoring with improved sensitivity and contrast.

BACKGROUND: Although B-mode imaging has been widely used in ultrasound-guided high-intensity focused ultrasound (HIFU) treatment, challenges remain in improving its quality and sensitivity for monitoring the thermal dose. Recently, quantitative ultrasound (QUS) imaging has been recognized with the potential to better sense the changes in the microstructure of ablated tissues. PURPOSE: This study proposed to use a QUS method called weighted ultrasound entropy (WUE) imaging to monitor the HIFU ablation. METHODS: Based on ex-vivo and in-vivo experiments, WUE images reflecting tissue changes during HIFU treatment under different acoustic power levels (174-308 W) were reconstructed with a newly established imaging framework. The performance of the proposed WUE imaging in the monitoring of HIFU treatment was compared with the corresponding B-mode images in terms of their contrast-to-noise ratios (CNRs) between the focal region and the background. RESULTS: It was found that HIFU irradiation with higher power generated larger WUE values in the focal region, and the bright spots grew in size as the acoustic sonication proceeded. Compared with the in-situ B-mode images, the WUE images had higher image quality in indicating lesion formation, with a 39.2%-53.4% improvement in the CNR at different stages. Meanwhile, a correlation (R = 0.84) between the damage area estimated in WUE images and that measured from the dissected ex-vivo tissue samples was found. CONCLUSIONS: WUE imaging is more sensitive and accurate than B-mode imaging in monitoring HIFU therapy. These findings suggest that WUE imaging could be a promising technique for assisting ultrasound-guided HIFU ablation.

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.

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.

Initial treatment for surgery-naïve desmoid tumors by high intensity focused ultrasound.

Introduction: Desmoid tumor (DT) is a rare proliferative disease occurring in connective tissues, characterized by high infiltration and recurrence rates. While surgery remains the primary treatment, its recurrence risk is high, and some extra-abdominal desmoid tumors are inoperable due to their locations. Despite attempts with radiotherapy and systemic therapy, the efficacy remains limited. Methods: We used low-power cumulative high-intensity focused ultrasound (HIFU) therapy as an initial treatment for desmoid tumor patients either ineligible or unwilling for surgery. Low-power cumulative HIFU employs slower heat accumulation and diffusion, minimizing damage to surrounding tissues while enhancing efficacy. Results: Fifty-seven non-FAP desmoid tumor patients, previously untreated surgically, underwent low-power cumulative HIFU therapy. Among them, 35 had abdominal wall DT, 20 had extra-abdominal DT, and 2 had intra- abdominal DT, with an 85% median ablation ratio. Abdominal wall DT patients showed significantly better response rates (91.4% vs. 86%) and disease control rates (100% vs. 32%) than that of non-abdominal wall DT patients. Median event- free survival time was not reached after a median follow-up duration of 34 months. Discussion: With its high response rate, durable efficacy, and mild adverse effects, our findings suggest that low-power cumulative HIFU presents a promising novel treatment for desmoid tumors, particularly abdominal wall DT patients.

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.

Prospective close monitoring of the effect of vascular-targeted photodynamic therapy and high intensity focused ultrasound of localized prostate cancer by multiparametric magnetic resonance imaging.

PURPOSE: The aim of this study is to describe the anatomical and functional changes observed in multiparametric magnetic resonance imaging (mpMRI) during follow-up after focal therapy (FT) for localized prostate cancer (PCa). MATERIALS AND METHODS: In this prospective study, we analyzed pre- and postoperatively acquired mpMRI of 10 patients after FT (7 days; 3, 6, 9, 12 months). 7/10 (70%) patients underwent vascular-targeted photodynamic therapy (VTP). 3/10 (30%) patients underwent high-intensity focused ultrasound (HIFU). MpMR image analysis was performed using a semi-automatic software for segmentation of the prostate gland (PG) and tumor zones. Signal intensities (SI) of T2-weighted (T2w), T1-weighted (T1w),diffusion-weighted (DWI) and dynamic contrast-enhanced (DCE) images as well as volumes of the prostate gland (PGV) and tumor volumes (TV) were evaluated at each time point. RESULTS: The results showed a significant increase of PGV 7 days after FT (p = 0.042) and a significant reduction of PGV between 7 days and 6, 9 and 12 months after FT (p < 0.001). The TV increased significantly 7 days after FT (p < 0.001) and decreased significantly between 7 days and 12 months after FT (p < 0.001). There was a significant increase in SI of the ADC in the ablation zone after 6, 9 and 12 months after FT (p < 0.001). 1/9 patients (11%) had recurrent tumor on rebiopsy characterized as a a small focal lesion on mpMRI with strong diffusion restriction (low SI on ADC map and high SI on b-value DWI). CONCLUSION: MpMRI is able to represent morphologic changes of the ablated zone after FT and might be helpful to detect recurrent tumor.

A novel scoring system based on magnetic resonance imaging for the prediction of the difficulty of ultrasound-guided high-intensity focused ultrasound ablation for uterine fibroids.

OBJECTIVE: To develop a novel scoring system based on magnetic resonance imaging (MRI) for predicting the difficulty of ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation for uterine fibroids. MATERIALS AND METHODS: A total of 637 patients with uterine fibroids were enrolled. Sonication time, non-perfused volume ratio (NPVR), and ultrasound energy delivered for ablating 1 mm3 of fibroid tissue volume (E/V) were each classified as three levels and assigned scores from 0 to 2, respectively. Treatment difficulty level was then assessed by adding up the scores of sonication time, NPVR and E/V for each patient. The patients with score lower than 3 were categorized into low difficulty group, with score equal to or greater than 3 were categorized into high difficulty group. The potential predictors for treatment difficulty were compared between the two groups. Multifactorial logistic regression analysis model was created by analyzing the variables. The difficulty score system was developed using the beta coefficients of the logistic model. RESULTS: Signal intensity on T2WI, fibroid location index, largest diameter of fibroids, abdominal wall thickness, homogeneity of the signal of fibroids, and uterine position were independent influencing factors for the difficulty of USgHIFU for uterine fibroids. A prediction equation was obtained: difficulty score = 17 × uterine position (anteverted =0, retroverted =1)+71 × signal intensity (hypointense = 0, isointense/hyperintense = 1) +8 × enhancement (homogenous = 0, heterogeneous = 1)+25×(largest diameter of fibroids-20) +35 × (fibroid location index -0.2) +1×(abdominal wall thickness -5). CONCLUSIONS: This scoring system established based on MRI findings can be used to reliably predict the difficulty level of USgHIFU treatment of uterine fibroids.

Ultrasound Combination to Improve the Efficacy of Current Boron Neutron Capture Therapy for Head and Neck Cancer.

Boron neutron capture therapy (BNCT) is radiotherapy in which a nuclear reaction between boron-10 (10B) in tumor cells and neutrons produces alpha particles and recoiling 7Li nuclei with an extremely short range, leading to the destruction of the tumor cells. Although the neutron source has traditionally been a nuclear reactor, accelerators to generate neutron beams have been developed and commercialized. Therefore, this treatment will become more widespread. Recurrent head and neck cancer (HNC) close to the body surface is considered a candidate for BNCT using the boron compound boronophenylalanine (BPA) and has been found to be highly responsive to this treatment. However, some cases recur early after the completion of the treatment, which needs to be addressed. Ultrasound is a highly safe diagnostic method. Ultrasound with microbubbles is expected to promote the uptake of BPA into tumor cells. Ultrasound also has the ability to improve the sensitivity of tumor cells to radiotherapy. In addition, high-intensity focused ultrasound may improve the efficacy of BNCT via its thermal and mechanical effects. This review is not systematic but outlines the current status of BPA-based BNCT and proposes plans to reduce the recurrence rate of HNC after BNCT in combination with ultrasound.

Development and validation of a deep learning-based method for automatic measurement of uterus, fibroid, and ablated volume in MRI after MR-HIFU treatment of uterine fibroids.

INTRODUCTION: The non-perfused volume divided by total fibroid load (NPV/TFL) is a predictive outcome parameter for MRI-guided high-intensity focused ultrasound (MR-HIFU) treatments of uterine fibroids, which is related to long-term symptom relief. In current clinical practice, the MR-HIFU outcome parameters are typically determined by visual inspection, so an automated computer-aided method could facilitate objective outcome quantification. The objective of this study was to develop and evaluate a deep learning-based segmentation algorithm for volume measurements of the uterus, uterine fibroids, and NPVs in MRI in order to automatically quantify the NPV/TFL. MATERIALS AND METHODS: A segmentation pipeline was developed and evaluated using expert manual segmentations of MRI scans of 115 uterine fibroid patients, screened for and/or undergoing MR-HIFU treatment. The pipeline contained three separate neural networks, one per target structure. The first step in the pipeline was uterus segmentation from contrast-enhanced (CE)-T1w scans. This segmentation was subsequently used to remove non-uterus background tissue for NPV and fibroid segmentation. In the following step, NPVs were segmented from uterus-only CE-T1w scans. Finally, fibroids were segmented from uterus-only T2w scans. The segmentations were used to calculate the volume for each structure. Reliability and agreement between manual and automatic segmentations, volumes, and NPV/TFLs were assessed. RESULTS: For treatment scans, the Dice similarity coefficients (DSC) between the manually and automatically obtained segmentations were 0.90 (uterus), 0.84 (NPV) and 0.74 (fibroid). Intraclass correlation coefficients (ICC) were 1.00 [0.99, 1.00] (uterus), 0.99 [0.98, 1.00] (NPV) and 0.98 [0.95, 0.99] (fibroid) between manually and automatically derived volumes. For manually and automatically derived NPV/TFLs, the mean difference was 5% [-41%, 51%] (ICC: 0.66 [0.32, 0.85]). CONCLUSION: The algorithm presented in this study automatically calculates uterus volume, fibroid load, and NPVs, which could lead to more objective outcome quantification after MR-HIFU treatments of uterine fibroids in comparison to visual inspection. When robustness has been ascertained in a future study, this tool may eventually be employed in clinical practice to automatically measure the NPV/TFL after MR-HIFU procedures of uterine fibroids.