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.

Effectiveness of high-intensity focused ultrasound combined with gonadotropin-releasing hormone agonist or combined with levonorgestrel-releasing intrauterine system for adenomyosis: A systematic review and meta-analysis.

Gonadotropin-Releasing Hormone Agonist (GnRH-a) and levonorgestrel releasing intrauterine system (LNG-IUS) are conventional conservative treatments for adenomyosis, and high-intensity focused ultrasound (HIFU) is a novel ablation technique. This study aimed to investigate the effectiveness of HIFU combined with GnRH-a or LNG-IUS for adenomyosis patients. In this systematic review and meta-analysis, Pubmed, Embase, Cochrane Library and Scopus databases were searched up to December 2021. Published studies comparing HIFU plus GnRH-a with HIFU plus LNG-IUS in adenomyosis patients were assessed for eligibility by two independent authors. Risk of bias tool was utilized for risk evaluation. We selected treatment effective rate of dysmenorrhea (pain during menstruation) as the primary outcome; effective rate of menorrhagia severity and reduction rate of adenomyotic lesion as the secondary outcomes. Adverse effects were assessed. Four studies with a total 729 patients were enrolled in the meta-analysis. HIFU plus LNG-IUS showed lower dysmenorrhea [within 6 months: risk ratio (RR) 0.88, 95% confidence interval (CI) 0.83-0.93, p < 0.00001; over 1 year: RR 0.73, 95% CI 0.65-0.82, p < 0.00001] and less menorrhagia severity (RR 0.63, 95% CI 0.60-0.66, p < 0.00001) than HIFU plus GnRH-a. Both groups demonstrated equal efficacy in adenomyotic lesion reduction rate (RR 1.03, 95% CI 0.97-1.09, p = 0.30). Adverse effects happened equally in both groups. Combination therapy of HIFU and LNG-IUS revealed better effectiveness in treating dysmenorrhea and menorrhagia than that of HIFU and GnRH-a. However, interpreting the conclusion should be approached with caution as a result of significant heterogeneity.

High-intensity Focused Ultrasound is a Better Choice for Women with Fertility Desire: A Systematic Review and Meta-analysis of the Comparison between High-intensity Focused Ultrasound and Laparoscopic Treatment of Uterine Fibroids.

High-intensity focused ultrasound (HIFU) is commonly used to treat uterine fibroids and adenomyosis, but there is no evidence using metadata to compare fertility outcomes between conventional laparoscopic procedures and HIFU. The purpose of this study analysis is that evidence-based fertility outcomes may provide better treatment options for clinicians and patients considering fertility. The literature on fertility data for HIFU surgery versus laparoscopic myomectomy was searched in seven English language databases from January 1, 2010, to November 23, 2022. A total of 1375 articles were received in the literature, 14 of which were selected. We found that women who underwent HIFU surgery had higher rates of spontaneous pregnancy, higher rates of spontaneous delivery, and higher rates of full-term delivery but may have higher rates of miscarriage or postpartum complications than women who underwent laparoscopic myomectomy. Looking forward to future studies, it is hoped that the literature will examine endometrial differences in women who undergo HIFU and laparoscopic myomectomy to demonstrate the ability of endometrial repair. The location of fibroids in the sample should also be counted to allow for attribution statistics on the cause of miscarriage.

Feasibility, safety and efficacy of high intensity focused ultrasound ablation as a preoperative treatment for challenging hysteroscopic myomectomy.

PURPOSE: To investigate the feasibility, safety and efficacy of high intensity focused ultrasound ablation (HIFU) as a preoperative treatment for challenging hysteroscopic myomectomies. MATERIALS AND METHODS: A total of 75 patients diagnosed with types 0-III of uterine fibroids were enrolled. Based on the Size, Topography, Extension of the base, Penetration and lateral Wall position (STEPW) classification scoring system, 25 cases with a score ≥ 5 points were treated with HIFU followed by hysteroscopic myomectomy (HIFU + HM group), whereas 50 cases with a score < 5 points were treated with hysteroscopic myomectomy (HM group). RESULTS: The median preoperative STEPW score was 7 in the HIFU + HM group and 2 in the HM group. The average non-perfused volume (NPV) ratio achieved in fibroids after HIFU was 86.87%. Patients in the HIFU + HM group underwent hysteroscopic myomectomy one to four days after HIFU, and downgrading was observed in 81.81% of fibroids. The operation time for patients in the HIFU + HM group was 73 min and the success rate of myomectomy in a single attempt was 60%. The volume of distention medium used during the operation was greater in the HIFU + HM group than in the HM group (15,500 ml vs. 7500 ml). No significant difference was observed between the two groups in terms of intraoperative blood loss, the incidence of intraoperative and postoperative complications, menstrual volume score, or uterine fibroid quality of life score. CONCLUSION: HIFU can be utilized as a preoperative treatment for large submucosal fibroids prior to hysteroscopic myomectomy. HIFU offers a novel approach in the management of this subset of patients.

Intravoxel incoherent motion (IVIM)-derived perfusion fraction mapping for the visual evaluation of MR-guided high intensity focused ultrasound (MR-HIFU) ablation of uterine fibroids.

BACKGROUND: A method for periprocedural contrast agent-free visualization of uterine fibroid perfusion could potentially shorten magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) treatment times and improve outcomes. Our goal was to test feasibility of perfusion fraction mapping by intravoxel incoherent motion (IVIM) modeling using diffusion-weighted MRI as method for visual evaluation of MR-HIFU treatment progression. METHODS: Conventional and T2-corrected IVIM-derived perfusion fraction maps were retrospectively calculated by applying two fitting methods to diffusion-weighted MRI data (b = 0, 50, 100, 200, 400, 600 and 800 s/mm2 at 1.5 T) from forty-four premenopausal women who underwent MR-HIFU ablation treatment of uterine fibroids. Contrast in perfusion fraction maps between areas with low perfusion fraction and surrounding tissue in the target uterine fibroid immediately following MR-HIFU treatment was evaluated. Additionally, the Dice similarity coefficient (DSC) was calculated between delineated areas with low IVIM-derived perfusion fraction and hypoperfusion based on CE-T1w. RESULTS: Average perfusion fraction ranged between 0.068 and 0.083 in areas with low perfusion fraction based on visual assessment, and between 0.256 and 0.335 in surrounding tissues (all p < 0.001). DSCs ranged from 0.714 to 0.734 between areas with low perfusion fraction and the CE-T1w derived non-perfused areas, with excellent intraobserver reliability of the delineated areas (ICC 0.97). CONCLUSION: The MR-HIFU treatment effect in uterine fibroids can be visualized using IVIM perfusion fraction mapping, in moderate concordance with contrast enhanced MRI. IVIM perfusion fraction mapping has therefore the potential to serve as a contrast agent-free imaging method to visualize the MR-HIFU treatment progression in uterine fibroids.

Focal therapy with high-intensity focused ultrasound for prostate cancer: 3-year outcomes from a prospective trial.

OBJECTIVE: To assess the oncological and functional outcomes of focal high-intensity focused ultrasound (HIFU) in treating localised prostate cancer (PCa), a 3-year prospective study was undertaken using periodic post-ablation saturation biopsies. PATIENTS AND METHODS: Men with two or fewer lesions of grade group (GG) ≤3 PCa were eligible for participation. Additional criteria included a prostate-specific antigen (PSA) level of ≤15 ng/mL, clinical T1c-T2, and a life expectancy of ≥10 years. The primary endpoint was failure-free survival (FFS), defined as absence of clinically significant PCa (csPCa) in- or out-of-field on protocol-mandated saturation biopsy, no whole-gland or systemic salvage treatment, PCa metastasis, or PCa-related death. Results are reported using two distinct definitions of csPCa: (i) the presence of any GG ≥2 and (ii) any GG ≥3 or core involvement of ≥6 mm. Secondary endpoints were functional patient-reported outcome measures addressing urinary, sexual, and bowel function. RESULTS: A total of 91 patients were included: six (7%) with GG1 and 85 (93%) with GG ≥2. In all, 83 (91%) underwent at least one follow-up biopsy. Biopsy attendance at 6, 12, and 36 months was 84%, 67%, and 51%, respectively. The FFS at these time points for any GG ≥2 PCa was 79% (95% confidence interval [CI] 80-88%), 57% (95% CI 48-69%) and 44% (95% CI 34-56%), respectively. Using the second definition, FFS were 88% (95% CI 81-95%), 70% (95% CI 61-81%) and 65% (95% CI 55-77%), respectively. The 3-year cancer-specific survival was 100%, and freedom from metastasis was 99%. Magnetic resonance imaging (MRI) (negative predictive value of up to 89%, 95% CI 84-93%) and relative decrease of PSA values (P = 0.4) performed poorly in detecting residual disease. Urinary and bowel assessment returned to baseline questionnaire scores within 3 months. In all, 17 (21%) patients reported meaningful worsening in erectile function. A significant decrease of PCa related anxiety was observed. CONCLUSIONS: Focal HIFU treatment for localised PCa shows excellent functional outcomes with half of the patients remaining cancer-free after 3 years. Whole-gland treatment was avoided in 81%. Early follow-up biopsies are crucial to change or continue the treatment modality at the right time, while the use of MRI and PSA in detecting PCa recurrence is uncertain.

Efficacy of HIFU for the treatment of benign thyroid nodules: a systematic review and meta-analysis.

OBJECTIVE: Thyroid nodules are common and sometimes associated with cosmetic issues. Surgical treatment has several disadvantages, including visible scarring. High-intensity focused ultrasound (HIFU) is a recent noninvasive treatment for thyroid nodules. The present study aims to evaluate the effectiveness and safety of HIFU for the treatment of benign thyroid nodules. METHODS: We searched PubMed, Embase, and Cochrane Library for studies evaluating the outcomes of HIFU for patients with benign thyroid nodules. We conducted a meta-analysis by using a random effects model and evaluated the volume reduction ratio, treatment success rate, and incidence of treatment-related complications. RESULTS: Thirty-two studies were included in the systematic review. Only 14 studies were used in the meta-analysis because the other 18 involved data collected during overlapping periods. The average volume reduction ratios at 3, 6, and 12 months after treatment were 39.02% (95% CI: 27.57 to 50.47%, I2: 97.9%), 48.55% (95% CI: 35.53 to 61.57%, I2: 98.2%), and 55.02% (95% CI: 41.55 to 68.48%, I2: 99%), respectively. Regarding complications, the incidences of vocal cord paresis and Horner's syndrome after HIFU were 2.1% (95% CI: 0.2 to 4.1%, I2: 14.6%) and 0.7% (95% CI: 0 to 1.9%, I2: 0%), respectively. CONCLUSIONS: HIFU is an effective and safe treatment option for patients with benign thyroid nodules. However, the effects of HIFU on nodules of large sizes and with different properties require further investigation. Additional studies, particularly randomized controlled trials involving long-term follow-up, are warranted. CLINICAL RELEVANCE STATEMENT: Surgical treatment for thyroid nodules often results in permanent visible scars and is associated with a risk of bleeding, nerve injury, and hypothyroidism. High-intensity focused ultrasound may be an alternative for patients with benign thyroid nodules. KEY POINTS: • The success rate of HIFU treatment for thyroid nodules is 75.8% at 6 months. Average volume reduction ratios are 48.55% and 55.02% at 6 and 12 months. • The incidence of complications such as vocal fold paresis, Horner's syndrome, recurrent laryngeal nerve palsy, hypothyroidism, and skin redness is low. • HIFU is both effective and safe as a treatment for benign thyroid nodules.

Innovative Experimental Ultrasound and US-Related Techniques Using the Murine Model in Pancreatic Ductal Adenocarcinoma: A Systematic Review.

Pancreatic ductal adenocarcinoma (PDAC) is a cancer with one of the highest mortality rates in the world. Several studies have been conductedusing preclinical experiments in mice to find new therapeutic strategies. Experimental ultrasound, in expert hands, is a safe, multifaceted, and relatively not-expensive device that helps researchers in several ways. In this systematic review, we propose a summary of the applications of ultrasonography in a preclinical mouse model of PDAC. Eighty-eight studies met our inclusion criteria. The included studies could be divided into seven main topics: ultrasound in pancreatic cancer diagnosis and progression (n: 21); dynamic contrast-enhanced ultrasound (DCE-US) (n: 5); microbubble ultra-sound-mediated drug delivery; focused ultrasound (n: 23); sonodynamic therapy (SDT) (n: 7); harmonic motion elastography (HME) and shear wave elastography (SWE) (n: 6); ultrasound-guided procedures (n: 9). In six cases, the articles fit into two or more sections. In conclusion, ultrasound can be a really useful, eclectic, and ductile tool in different diagnostic areas, not only regarding diagnosis but also in therapy, pharmacological and interventional treatment, and follow-up. All these multiple possibilities of use certainly represent a good starting point for the effective and wide use of murine ultrasonography in the study and comprehensive evaluation of pancreatic cancer.

Four-tract probabilistic tractography technique for target selection in essential tremor treatment with magnetic resonance-guided focused ultrasound.

OBJECTIVES: Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is a novel, minimally invasive ablative treatment for essential tremor (ET). The use of a four-tract probabilistic tractography technique, targeting the intersection between the dentato-rubro-thalamic tracts (both decussating and non-decussating), while evaluating the corticospinal tract and the medial lemniscus, may obtain immediate clinical results with reduced adverse events. Our aim is to present our experience with the four-tract technique for patients undergoing ET treatment with MRgFUS. METHODS: Retrospective analysis of a prospective database of consecutive patients undergoing ET treatment in a single center from February 2022 to February 2023. Procedural parameters were collected, and tremor improvement was assessed with the Clinical Rating Scale for Tremor (CRST) at baseline and at 3 and 6 months. Adverse events were also reported. RESULTS: Forty-three patients (median age, 72 years [interquartile range, 66-76]; 22 females) were evaluated. Tremor improved significatively in all CRST subsections at 3 months, including the CRST part A + B treated hand tremor (22 [19-27] vs 4 [2-7], p < 0.001) and CRST part C (16 [13-19] vs 3 [1-4], p < 0.001). Differences persisted significant at 6 months. Adverse events were few (4.1% of paresthesias and 12.5% of objective gait disturbance at follow-up) and recorded as mild. The median number of sonications was 7 [6-8] and mean operative time 68.7 ± 24.2 min. CONCLUSION: Our data show support for the feasibility and benefits of systematic targeting approach with four-tract probabilistic tractography for treating ET using MRgFUS. CLINICAL RELEVANCE STATEMENT: An approach with four-tract probabilistic tractography for treating essential tremor (ET) patients with magnetic resonance-guided focused ultrasound decreases interindividual variability with good clinical outcomes, low number of sonications, few adverse effects, and short procedure times. KEY POINTS: • The optimal target for the treatment of essential tremor with MR-guided focused ultrasound remains unknown. • Four-tract probabilistic tractography is a feasible technique that reduces interindividual variability, with good clinical results, few side effects, and short operative time. • The four-tract tractography approach can be performed using different MRI scanners and post-processing software in comparison with the initial description of the technique.

Combination of HIFU with sulfur hexafluoride microbubbles in the treatment of solitary uterine fibroids: a systematic review and meta-analysis.

OBJECTIVES: To assess the efficacy and safety of sulfur hexafluoride microbubbles on ultrasound-guided high-intensity focused ultrasound (HIFU) ablation of uterine fibroids. METHODS: Studies that compared HIFU-microbubble combination with HIFU-only in patients with uterine fibroids were searched from inception to April 2022. The standardized mean difference (SMD) or relative risk (RR) with 95% confidence interval (CI) for different outcome parameters was calculated. RESULTS: Seven studies were included, with a total of 901 patients (519 in the combination group and 382 in the HIFU-only group). The energy consumption for treating 1 cm3 of the lesion in the combination group was less than that in the HIFU-only group [SMD = - 2.19, 95%CI (- 3.81, - 0.57), p = 0.008]. The use of microbubbles was associated with shortening the duration of the treatment and sonication [SMD = - 2.60, 95%CI (- 4.09, - 1.10), p = 0.0007; SMD = - 2.11, 95%CI (- 3.30, - 0.92), p = 0.0005]. The rates of significant greyscale changes during HIFU were greater in the combination group, as well as the increase of non-perfused volume ratio [RR = 1.26, 95%CI (1.04, 1.54), p = 0.02; SMD = 0.32, 95%CI (0.03, 0.61), p = 0.03]. The average sonication durations to reach significant greyscale changes and for ablating 1 cm3 of the fibroid lesion were shorter in the combination group [SMD = - 1.24, 95%CI (- 2.02, - 0.45), p = 0.002; SMD = - 0.22, 95%CI (- 0.42, - 0.02), p = 0.03]. The two groups had similar post-HIFU adverse effects, while the combination group had fewer intraprocedural adverse events like abdominal pain, sacrum pain, and leg pain. CONCLUSIONS: Sulfur hexafluoride microbubbles can be safely used to enhance and accelerate the ablation effects of HIFU in the treatment of uterine fibroids. CLINICAL RELEVANCE STATEMENT: The combination of HIFU with sulfur hexafluoride microbubbles offers a promising non-invasive treatment option for patients with uterine fibroids. KEY POINTS: • Sulfur hexafluoride microbubbles combined with ultrasound-guided high-intensity focused ultrasound (USgHIFU) has potential advantages in the treatment of uterine fibroids. • Sulfur hexafluoride microbubbles not only enhance the effects of USgHIFU treatment for uterine fibroids but also shorten its duration. • Sulfur hexafluoride microbubbles do not increase the incidence of USgHIFU-related adverse events in the treatment of uterine fibroids.

Partial gland ablation using high-intensity focused ultrasound versus robot-assisted radical prostatectomy: a propensity score-matched study.

Background: We compared the clinical outcomes of robot-assisted radical prostatectomy (RARP) and partial gland ablation (PGA) using high-intensity focused ultrasound (HIFU) in localized prostate cancer. Methods: We analyzed 3,859 patients who had undergone RARP and PGA using HIFU. According to the propensity score for each treatment, 137 patients after PGA were matched to 3,722 patients after RARP at a 1:4 ratio using the nearest neighbor method. Results: The matched cohort comprised 685 subjects (RARP, 548; PGA, 137), with a median follow-up period of 22 months. Treatment failures were identified in 13.9% and 9.1% of patients in the PGA and RARP groups, respectively, after a median follow-up of 36 months postoperatively. Kaplan-Meier analyses revealed significantly longer failure-free (P < 0.001) and salvage-free survival (P = 0.003) in the RARP group than in the PGA group. There was no significant difference in the postoperative urinary symptom score (P = 0.748), but the postoperative erectile function score was significantly higher in the PGA group (P < 0.001). The rate of urinary incontinence (any pad) was significantly lower in the PGA group than that in the RARP group (P < 0.001). Postoperative complications were more frequent in the PGA group (P = 0.003); however, there was no significant difference in high-grade complications (≥3) (P = 0.467). Conclusion: PGA using HIFU showed statistically inferior oncological outcomes compared with RARP for failure-free survival and salvage-free survival. However, functional outcomes regarding postoperative incontinence and erectile dysfunction were more favorable in the PGA group.

Diagnostic performance of MRI for prediction of recurrent prostate cancer after high-intensity focused ultrasound: a systematic review and meta-analysis.

Purpose: This article aims to evaluate the pooled diagnostic performance control MRI for prediction of recurrent prostate cancer (PCa) after high-intensity focused ultrasound (HIFU). Materials and methods: MEDLINE, EMBASE, and Cochrane library databases up to December 31, 2021, were searched. We included studies providing 2×2 contingency table for diagnostic performance of MRI in predicting recurrent PCa after HIFU, using control biopsy as reference standard. The quality of the included studies was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Sensitivity and specificity were pooled and displayed in a summary receiver operating characteristics (SROC) plot. Meta-regression analysis using clinically relevant covariates was performed for the causes of heterogeneity. Results: Nineteen studies (703 patients) were included. All included studies satisfied at least four of the seven QUADAS-2 domains. Pooled sensitivity was 0.81 (95% CI 0.72-0.90) with specificity of 0.91 (95% CI 0.86-0.96), with area under the SROC curve of 0.81. Larger studies including more than 50 patients showed relatively poor sensitivity (0.68 vs. 0.84) and specificity (0.75 vs. 0.93). The diagnostic performance of studies reporting higher nadir serum prostate-specific antigen levels (>1 ng/mL) after HIFU was inferior, and differed significantly in sensitivity (0.54 vs. 0.78) rather than specificity (0.85 vs. 0.91). Conclusions: Although MRI showed adequate diagnostic performance in predicting PCa recurrence after HIFU, these results may have been exaggerated.

Prostate Imaging after Focal Ablation (PI-FAB): A Proposal for a Scoring System for Multiparametric MRI of the Prostate After Focal Therapy.

At present there is no standardised system for scoring the appearance of the prostate on multiparametric magnetic resonance imaging (MRI) after focal ablation for localised prostate cancer. We propose a novel scoring system, the Prostate Imaging after Focal Ablation (PI-FAB) score, to fill this gap. PI-FAB involves a 3-point scale for rating MRI sequences in sequential order: (1) dynamic contrast-enhanced sequences; (2) diffusion-weighted imaging, split into assessment of the high-b-value sequence first and then the apparent diffusion coefficient map; and (3) T2-weighted imaging. It is essential that the pretreatment scan is also available to help with this assessment. We designed PI-FAB using our experience of reading postablation scans over the past 15 years and include details for four representative patients initially treated with high-intensity focus ultrasound at our institution to demonstrate the scoring system. We propose PI-FAB as a standardised method for evaluating prostate MRI scans after treatment with focal ablation. The next step is to evaluate its performance across multiple experienced readers of MRI after focal therapy in a clinical data set. PATIENT SUMMARY: We propose a scoring system called PI-FAB for assessing the appearance of magnetic resonance imaging scans of the prostate after focal treatment for localised prostate cancer. This will help clinicians in deciding on further follow-up.

High intensity focused ultrasound treatment for adenomyosis: comparison of efficacy based on MRI features.

OBJECTIVE: To compare the clinical efficacy of High intensity-focused ultrasound(HIFU) for different types of adenomyosis classified by magnetic resonance imaging (MRI). METHODS: A total of 227 patients with adenomyosis who underwent HIFU treatment in Suining Central Hospital from January 2014 to December 2019 were included. Based on the preoperative pelvic MRI examination and Kishi isometric classification method, the patients were divided into 4 types according to the location of lesions. There were 82 cases of type I (endogenous type), 75 cases of type II (exogenous type), 34 cases of type III (nodular type), and 36 cases of type IV (heterogeneous type). The results of HIFU treatment for four types of adenomyosis and intraoperative adverse effects were analyzed. The changes of lesion size, dysmenorrhea, and menstrual volume were analyzed at 3 and 6 months after the operation. RESULT: (1) adverse effects: All patients successfully accepted HIFU treatment under sedation and analgesia. Grade A adverse effects occurred in 51 cases (22.47%) and grade B adverse effects in 3 cases (1.32%). The incidence of adverse effects in type I-IV patients was 21.95%, 22.66%, 23.53%, and 30.56%, respectively. There was no significant difference in the incidence of grade A and B adverse effects in all types, and no grade C-F adverse effects occurred. (2) Ablation effect: The ablation rate of type III(nodular type)patients was (74.7 ± 20.3) %, which was significantly higher than that of the other three types (p < .05). (3) Changes in lesion size: the lesion size of all patients decreased after treatment and the reduction rate gradually increased with time. At 6 months after the operation, the lesion reduction rate of type III patients was (70.8 ± 14.8) %, higher than that of the other three types patients (p < .05). There was no significant difference in the reduction rate of type I, type II and type IV. (4) Remission of menorrhagia: At 6 months after the operation, the total remission rate of type III patients was 100%, while the total remission rate of type IV patients (65.4%, 17/26) that was lower than that of type I, II and III patients(p < .05). (5) Dysmenorrhea relief: At 6 months after the operation, the total dysmenorrhea relief rate of type III patients was 100% and the complete relief rate (28.1%, 18/31) was higher than that of the other three types, which was significant differences (p < .05). CONCLUSIONS: HIFU is safe and effective in the treatment of different types of adenomyosis, the therapeutic effect of HIFU in patients with type III adenomyosis is better than that of the other three types.

Evaluation of Outcomes Following Focal Ablative Therapy for Treatment of Localized Clinically Significant Prostate Cancer in Patients >70 Years: A Multi-institute, Multi-energy 15-Year Experience.

PURPOSE: In older patients who do not wish to undergo watchful waiting, focal therapy could be an alternative to the more morbid radical treatment. We evaluated the role of focal therapy in patients 70 years and older as an alternative management modality. MATERIALS AND METHODS: A total of 649 patients across 11 UK sites receiving focal high-intensity focused ultrasound or cryotherapy between June 2006 and July 2020 reported within the UK-based HEAT (HIFU Evaluation and Assessment of Treatment) and ICE (International Cryotherapy Evaluation) registries were evaluated. Primary outcome was failure-free survival, defined by need for more than 1 focal reablation, progression to radical treatment, development of metastases, need for systemic treatment, or prostate cancer-specific death. This was compared to the failure-free survival in patients undergoing radical treatment via a propensity score weighted analysis. RESULTS: Median age was 74 years (IQR: 72, 77) and median follow-up 24 months (IQR: 12, 41). Sixty percent had intermediate-risk disease and 35% high-risk disease. A total of 113 patients (17%) required further treatment. Sixteen had radical treatment and 44 required systemic treatment. Failure-free survival was 82% (95% CI: 76%-87%) at 5 years. Comparing patients who had radical therapy to those who had focal therapy, 5-year failure-free survival was 96% (95% CI: 93%-100%) and 82% (95% CI: 75%-91%) respectively (P < .001). Ninety-three percent of those in the radical treatment arm had received radiotherapy as their primary treatment with its associated use of androgen deprivation therapy, thereby leading to potential overestimation of treatment success in the radical treatment arm, especially given the similar metastases-free and overall survival rates seen. CONCLUSIONS: We propose focal therapy to be an effective management option for the older or comorbid patient who is unsuitable for or not willing to undergo radical treatment.

Therapeutic dose and long-term efficacy of high-intensity focused ultrasound ablation for different types of uterine fibroids based on signal intensity on T2-weighted MR images.

OBJECTIVE: To investigate the therapeutic dose and long-term efficacy of high-intensity focused ultrasound (HIFU) ablation for different types of uterine fibroids based on signal intensity on T2-weighted MR images (T2WI). MATERIALS AND METHODS: Four hundred and one patients with a solitary uterine fibroid treated with HIFU were classified into four groups consisting of extremely hypointense, hypointense, isointense and hyperintense fibroids. Each group was further classified into two subtypes: homogeneous and heterogeneous, based on signal homogeneity of fibroids. The therapeutic dose and long-term follow-up results were compared. RESULTS: There were significant differences in treatment time, sonication time, treatment intensity, total treatment dosage, treatment efficiency, energy-efficiency factor (EEF) and non-perfused volume (NPV) ratio among the four groups (p<.05). The average NPV ratio achieved in patients with extremely hypointense, hypointense, isointense and hyperintense fibroids was 75.2 ± 14.6%, 71.1 ± 15.6%, 68.2 ± 17.3% and 67.8 ± 16.6%, respectively; the re-intervention rates at 36 months after HIFU were 8.4%, 10.3%, 12.5% and 6.1%, respectively. Sonication time, treatment intensity and total energy for heterogeneous fibroids were greater than that for homogeneous fibroids in patients with extremely hypointense fibroids (p<.05). The treatment time for heterogeneous fibroids was significantly longer than that for homogeneous fibroids in patients with isointense fibroids (p<.05). Multivariate ordered logistic regression analysis showed that the ablation volume of fibroids and treatment time were related to NPV ratio (p<.05). CONCLUSION: Every group of patients obtained satisfactory long-term results. Hyperintense fibroids are difficult to treat by HIFU. Heterogeneous fibroids are more difficult to treat with HIFU than homogeneity fibroids.

Modeling for Quantitative Analysis of Nakagami Imaging in Accurate Detection and Monitoring of Therapeutic Lesions by High-Intensity Focused Ultrasound.

OBJECTIVE: Nakagami imaging is an appealing monitoring and evaluation technique for high-intensity focused ultrasound treatment when bubbles are present in ultrasound images. This study aimed to investigate the accuracy of thermal lesion detection using Nakagami imaging. METHODS: Simulations were conducted to explore and quantify the influence of the bubbles and the subresolvable effect at the boundary of the thermal lesion on thermal lesion detection. The thermal ablation experiments were conducted in phantom and porcine liver ex vivo. RESULTS: In the simulation, the estimated lateral and axial size of the thermal lesion in the Nakagami image was 4.91 and 4.79 mm, close to the actual size (5 × 5 mm). The simulation results indicated that the subresolvable region in high-intensity focused ultrasound treatment thermal ablation mainly happened at the boundary between bubbles and the untreated region and does not affect the accuracy of thermal lesion detection. The accurate detection of the thermal lesion using Nakagami imaging mainly depends on bubbles and thermal lesion characterization. Our thermal ablation experiments confirmed that Nakagami imaging has the ability to accurately identify thermal lesions from bubbles. CONCLUSION: The subresolvable effect is helpful for thermal lesion identification, and precision is related to the Nakagami values chosen for boundary division in Nakagami imaging. Therefore, Nakagami imaging is a promising method for accurately evaluating thermal lesions. Further studies in vivo and in clinical settings will be needed to explore its potential applications.

Magnetic Resonance Acoustic Radiation Force Imaging (MR-ARFI) for the monitoring of High Intensity Focused Ultrasound (HIFU) ablation in anisotropic tissue.

OBJECTIVE: We introduce a non-invasive MR-Acoustic Radiation Force Imaging (ARFI)-based elastography method that provides both the local shear modulus and temperature maps for the monitoring of High Intensity Focused Ultrasound (HIFU) therapy. MATERIALS AND METHODS: To take tissue anisotropy into account, the local shear modulus µ is determined in selected radial directions around the focal spot by fitting the phase profiles to a linear viscoelastic model, including tissue-specific mechanical relaxation time τ. MR-ARFI was evaluated on a calibrated phantom, then applied to the monitoring of HIFU in a gel phantom, ex vivo and in vivo porcine muscle tissue, in parallel with MR-thermometry. RESULTS: As expected, the shear modulus polar maps reflected the isotropy of phantoms and the anisotropy of muscle. In the HIFU monitoring experiments, both the shear modulus polar map and the thermometry map were updated with every pair of MR-ARFI phase images acquired with opposite MR-ARFI-encoding. The shear modulus was found to decrease (phantom and ex vivo) or increase (in vivo) during heating, before remaining steady during the cooling phase. The mechanical relaxation time, estimated pre- and post-HIFU, was found to vary in muscle tissue. DISCUSSION: MR-ARFI allowed for monitoring of viscoelasticity changes around the HIFU focal spot even in anisotropic muscle tissue.

High Intensity Focused Ultrasound Ablation for Patients With Locally Advanced Pancreatic Adenocarcinoma: A Propensity Score-Matching Analysis.

OBJECTIVES: This retrospective study was conducted to assess the efficacy and safety of high intensity focused ultrasound (HIFU) in combination with chemotherapy compared with chemotherapy alone in treating patients with unresectable locally advanced pancreatic cancer (LAPC). METHODS: The data of unresectable LAPC patients who received chemotherapy with or without HIFU ablation were retrieved retrospectively. The overall survival (OS), objective response rate (ORR), cancer antigen 19-9 response rate, and safety were compared between these two groups before and after propensity score matching (PSM). RESULTS: Overall, 254 patients with LAPC were included, of whom 92 underwent HIFU ablation. After PSM to control for potential biases, HIFU was associated with improved OS (12.8 versus 12.2 months, log-rank P = .046), as compared to patients without HIFU ablation. Patients with numeric rating scale (NRS) less than 4, and receiving HIFU ablation were significantly associated with improved OS (adjusted hazard ratio [aHR] = 0.365 [95% confidence interval (CI) = 0.148-0.655], P = .002; aHR = 0.490 [95% CI = 0.250-0.961], P = .038; respectively) by multivariate analyses with the adjustment of age, NRS, and tumor size. ORR was also observed to be higher in HIFU group of 30.0% than in the chemotherapy group of 13.3% (P = .039). No severe adverse events of special interest or HIFU-caused deaths were observed. CONCLUSIONS: Patients with unresectable LAPC who received gemcitabine-based chemotherapy might benefit from additional HIFU ablation.

Medium-term Oncological Efficacy and Patient-reported Outcomes After Focal High-intensity Focused Ultrasound: The FOXPRO Trial.

BACKGROUND: Multiparametric magnetic resonance imaging (mpMRI)/transrectal ultrasound (TRUS) fusion-guided high-intensity focused ultrasound (HIFU) is a focal treatment option for MRI-visible localized prostate cancer (PCa). High-quality evidence regarding the clinical efficacy remains limited. OBJECTIVE: To assess medium-term oncological efficacy along with patient-reported outcome measures (PROMs). DESIGN, SETTING, AND PARTICIPANTS: This prospective single-center cohort study was performed from 2014 to 2020. Patients with primary International Society of Urological Pathologists (ISUP) grade group (GG) ≤2 by combined MRI/TRUS fusion and systematic prostate biopsy and prostate-specific antigen (PSA) <10 ng/ml were included. INTERVENTION: MRI/TRUS fusion-guided focal HIFU therapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was the cancer-free rate of the HIFU-treated lesion by biopsy after 1 yr. Secondary endpoints included salvage treatment-free survival (STFS), metastasis-free survival (MFS), overall survival (OS), and PROMs according to International Consortium for Health Outcomes Measurement recommendations. RESULTS AND LIMITATIONS: Fifty patients were included (median [range] age 68 [48-80] yr; median PSA 6.5 [1.2-9.9] ng/ml; GG 1 54% [n = 27], and GG 2 46% [n = 23]). The median (range) PSA decrease from baseline to 12 mo was 51% (35.9-72.7%). In total, 37/50 patients (74%) underwent a 1-yr biopsy. PCa was detected in 23 patients (46%; GG 1 20% [n = 10]; GG >1 26% [n = 13]; infield 40% [n = 20]). At a median follow-up of 42 (13-73) mo, PCa was detected in 30 men (60%). Among all patients, 19 (38%) underwent salvage treatments (median [95% confidence interval] STFS 53 [44.3-61.7] mo). MFS and OS were 100% and 98%, respectively. The Expanded Prostate Cancer Index Composite-26 sexual domain decreased by 20.8 points (p = 0.372). CONCLUSIONS: MRI/TRUS-guided focal HIFU therapy results in complete cancer ablation in only half of the treated patients after 1 yr, with further recurrences at medium-term follow-up. A decline of potency occurs in a subset of patients. PATIENT SUMMARY: Focal image-guided high-intensity focused ultrasound therapy controls cancer in one of two patients. Its impact on urinary continence and erectile function is low.