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.

Family History and Uterine Fibroid Development in Black and African American Women.

Importance: Uterine fibroids are an understudied condition, with earlier onset in Black than White women. Prior studies of the importance of family history on fibroid development are limited by reliance on hospital-based participant selection, poorly defined measures of family history, and nonsystematic fibroid assessment. Objective: To examine whether family history is a risk factor for fibroid development using prospective ultrasonography data to identify incident fibroids and measure fibroid growth and standardized methods to ascertain family history. Design, Setting, and Participants: This prospective community cohort of Black and African American women from the Detroit, Michigan, area was conducted from January 1, 2010, to December 31, 2018, using 4 standardized ultrasonographic examinations during 5 years to detect fibroids 0.5 cm or larger in diameter and measure fibroid growth. Data analysis was performed between May 2022 and January 2024. Exposures: Maternal fibroid history data were gathered directly from participants' mothers when possible (1425/1628 [88%]), and 2 exposure variables were created: maternal history of fibroids (diagnosed vs not diagnosed) and age at maternal fibroid diagnosis (20-29, 30-39, or ≥40 years vs not diagnosed). Main Outcomes and Measures: Fibroid incidence was assessed using multivariable Cox proportional hazards regression models; fibroid growth was calculated as change in log-volume per 18 months for fibroids matched at successive ultrasonograms. Results: A total of 1610 self-identified Black and/or African American women aged 23 to 35 years (mean [SD] age, 29.2 [3.4] years) with no prior clinical diagnosis of fibroids at enrollment were available for analysis. Of 1187 fibroid-free participants at enrollment, 442 (37%) had mothers who were diagnosed with fibroids. Compared with participants without a maternal history of fibroids, those reporting maternal history had an adjusted hazard ratio (AHR) of 1.21 (95% CI, 0.96-1.52). Risk was strongest in those whose mothers were diagnosed at a younger age (20-29 years: AHR, 1.56; 95% CI, 1.11-2.21; 30-39 years: AHR, 1.03; 95% CI, 0.71-1.49; ≥40 years: AHR, 1.11; 95% CI, 0.81-1.52; P = .053 for trend). Fibroid growth rates were higher when mothers were diagnosed with fibroids vs not diagnosed (8.0% increased growth; 95% CI, -1.2% to 18.0%). Conclusions and Relevance: In this prospective cohort study, results supported maternal history of fibroids as a risk factor for incident fibroids, especially when mothers were diagnosed at a younger age. Maternal history was also associated with increased fibroid growth. Asking patients about their family history of fibroids could encourage patient self-advocacy and inform care.

Recurrent bladder leiomyoma: a case report.

BACKGROUND: Bladder leiomyomas are rare benign growths in the bladder, comprising less than 0.5% of bladder tumors with only 250 cases reported globally. They are more common in women. This case involves a 70-year-old woman with recurrent leiomyoma, presenting with lower urinary tract symptoms and painless hematuria. A recurrent bladder leiomyoma is rarely reported, making its presence exceptionally rare. CASE PRESENTATION: A 70-year-old Pakistani woman with hypertension and diabetes presented with lower urinary tract symptoms (LUTS) and painless hematuria. She had a history of similar symptoms in 2010, leading to a diagnosis of bladder leiomyoma via cystoscopy and biopsy. Imaging studies revealed a substantial 3.7 × 4 × 4.0 cm isodense mass with calcifications at the bladder base, along with bladder wall thickening and diverticula. Pathological examination during Transurethral Resection of Bladder Tumor (TURBT) confirmed the presence of bladder tissue with smooth muscle, ruling out malignancy. Immunohistochemical studies supported the diagnosis. A successful TURBT was performed, and the patient recovered well. DISCUSSION: Recurrent bladder leiomyoma is a rarely-discussed topic in medical literature. This article primarily aims to review existing studies and present a detailed case study, shedding light on this rare phenomenon.

Diagnostic and therapeutic approach to abdominal masses in a country with limited resources.

OBJECTIVE: To report the diagnostic and therapeutic approach for the management of abdominal masses in the General Surgery department of the Niamey General Reference Hospital (HGR). MATERIALS AND METHODS: This were a retrospective and preliminary study of 2 years and 3 months on patients operated for abdominal masses in the General Surgery department of the HGR. A palpable mass and/or its size on imaging (40 mm) were the inclusion criteria. RESULTS: Abdominal masses accounted for 6.7% (n = 53) of other pathologies. The average age of the patients was 41.26 years, with a standard deviation of 14.2 and a female predominance of 75.5% (n = 40) with a sex ratio of 0.32. The abdominal mass was clinically palpable in 75.5% (n = 40). Abdominal pelvic ultrasound was performed as a first step in all patients and in 75.5% (n = 40) it specified the origin of the mass. Contrast-enhanced abdomino-pelvic CT scan, performed in 52.8% of patients (n = 28) and in 89.3% (n = 25) specified the preoperative diagnosis. The most frequent etiologies were uterine fibroids, 35.8% (n = 19). In 5.6% (n = 3) the diagnosis was not precise preoperatively despite the two imaging studies, and these patients had underwent exploratory laparotomy. Surgery was the initial therapeutic approach for all patients, and laparoscopy accounted for 22.6% (n = 12). Postoperative complications occurred in 7.5% (n = 11). The death rate was 5.6% of cases (n = 3). CONCLUSION: Imaging remains important in the etiological research for abdominal masses. Definitive treatment remains surgical; mortality would be linked to the malignant nature and the significant volume of the mass.

Submucous leiomyoma: an uncommon cause of heavy menstrual bleeding in early adolescence.

Uterine leiomyomas are rare in the paediatric population. This report describes a rare case of a submucous leiomyoma in an adolescent girl. The patient presented with a history of abnormal and painful period which was refractory to medical treatment. Sonographic findings revealed a uterine mass that protruded through the cervix until the upper third of the vagina. A hysteroscopic resection was performed, and a pathological examination confirmed a leiomyoma. 12 months after surgery, there were no signs of recurrence. Conservative sparing-fertility management, such as hysteroscopic resection, is the best option with a type 0 submucosal fibroid, especially in adolescents and young women.

Uterine fibroids and longitudinal profiles of the vaginal microbiota in a cohort presenting for transvaginal ultrasound.

Bacterial vaginosis, characterized in part by low levels of vaginal Lactobacillus species, has been associated with pro-inflammatory cytokines which could fuel uterine fibroid development. However, prior work on the associations between uterine fibroids and vaginal bacteria is sparse. Most studies have focused on assessment of individual taxa in a single sample. To address research gaps, we sought to compare short, longitudinal profiles of the vaginal microbiota in uterine fibroid cases versus controls with assessment for hormonal contraceptives (HCs), a possible confounder associated with both protection from fibroid development and increases in Lactobacillus-dominated vaginal microbiota. This is a secondary analysis of 83 reproductive-age cisgender women who presented for transvaginal ultrasound (TVUS) and self-collected mid-vaginal swabs daily for 1-2 weeks before TVUS (Range: 5-16 days, n = 697 samples). Sonography reports detailed uterine fibroid characteristics (N = 21 cases). Vaginal microbiota was assessed by 16S rRNA gene amplicon sequencing and longitudinal microbiota profiles were categorized by hierarchical clustering. We compared longitudinal profiles of the vaginal microbiota among fibroid cases and controls with exact logistic regression. Common indications for TVUS included pelvic mass (34%) and pelvic pain (39%). Fibroid cases tended to be older and report Black race. Cases less often reported HCs versus controls (32% vs. 58%). A larger proportion of cases had low-Lactobacillus longitudinal profiles (48%) than controls (34%). In unadjusted analysis, L. iners-dominated and low-Lactobacillus profiles had higher odds of fibroid case status compared to other Lactobacillus-dominated profiles, however these results were not statistically significant. No association between vaginal microbiota and fibroids was observed after adjusting for race, HC and menstruation. Results were consistent when number of fibroids were considered. There was not a statistically significant association between longitudinal profiles of vaginal microbiota and uterine fibroids after adjustment for common confounders; however, the study was limited by small sample size.

Uncommon Detection of Leiomyoma in the Penile Corpus Spongiosum Using FDG PET/CT: A Case Report.

ABSTRACT: Primary tumors of the penile corpus spongiosum are rare. Hereby we describe the scintigraphic findings of a case of penile leiomyoma within the corpus spongiosum tissue, which was incidentally detected on FDG PET/CT. The benign neoplasm was growing in close proximity to the urethra showing increased focal FDG uptake on sequential PET/CT studies. Subsequently, the patient experienced obstructive urinary symptoms, and the tumor was resected. We concluded that the possibility of neoplasm should be kept in mind while evaluating a patient with persistent focal penile FDG uptake, which may be the first and only manifestation of the disease.

Evaluating the Effects of Water Balloons on High-Intensity Focused Ultrasound for Treating Uterine Fibroids.

OBJECTIVE: In the treatment of uterine fibroids with ultrasound-guided high-intensity focused ultrasound (HIFU), water balloons are considered to be a valuable aid for improving safety and efficiency. However, the water balloons worsen the pathway for acoustic transmission, causing degraded performance both in ultrasound therapy and in ultrasound imaging. This study was aimed at establishing a protocol to evaluate the effects of the water balloon. METHODS: Simulations and experiments were carefully conducted to quantitatively investigate the effects of water ballons on the efficiency of HIFU energy delivery and on the quality of ultrasound guiding images. More specifically, HIFU-induced temperature increases in the focal region, together with spatial resolution, contrast and signal-to-noise ratio in the ultrasound guiding images, were compared under the conditions with and without the water balloon. RESULTS: Experiment results revealed that the use of water balloons led to decreases in temperature up to 10ºC within the focal region in some specific situations, but the quality of the guiding images was relatively less affected. CONCLUSION: The study provided knowledge on what influence the water balloon could have in ultrasound-guided HIFU treatment; it also established a practical and standardized evaluation scheme for further optimizing the water balloon, for example, its material and internal liquid compositions. This study can potentially help improve the efficiency and safety of treating uterine fibroids with ultrasound-guided HIFU systems.

Giant orbital leiomyoma in a pediatric patient: diagnostic and therapeutic challenge.

This manuscript describes an exceptional case of a long-standing orbital leiomyoma in a 14-year-old male. The tumor was unusually large, causing severe proptosis and significant involvement of the ocular muscles. The patient presented with amaurosis, complete ophthalmoplegia, spontaneous eye pain, and the inability to close the eyelids, leading to psychological distress. Due to the tumor's size and progression, a right orbital exenteration was performed to remove all orbital contents, including the tumor and the eyeball. The surgical procedure aimed to prevent tumor recurrence and improve the patient's quality of life. The histopathological analysis confirmed the diagnosis of orbital leiomyoma. This case presents a particular interest due to the degree of evolution it has reached. Complete tumor excision and long-term follow-up are necessary to prevent recurrence and ensure optimal patient outcomes. This report underscores global healthcare disparities and the complexity of managing rare orbital neoplasms in diverse country settings.

Long-term outcome and risk factors of reintervention after high intensity focused ultrasound ablation for uterine fibroids: a systematic review and meta-analysis.

OBJECTIVES: To quantify the reintervention rate and analyze the risk factors for reintervention after high-intensity focused ultrasound (HIFU) ablation of uterine fibroids. METHODS: Eighteen studies were selected from the seven databases. A meta-analysis was applied to synthesize the reintervention rates for fibroids across various follow-up durations. Subgroup-analysis was conducted based on the year of surgery, sample size, guide methods, and non-perfusion volume ratio (NPVR). Signal intensity of T2-weighted imaging (T2WI) was independently evaluated for reintervention risk. RESULTS: The study enrolled 5216 patients with fibroids treated with HIFU. There were 3247, 1239, 1762, and 2535 women reaching reintervention rates of 1% (95% confidence interval (CI): 1-1), 7% (95% CI: 4-11), 19% (95% CI: 11-27), and 29% (95% CI: 14-44) at 12, 24, 36, and 60-month after HIFU. The reintervention rates of patients treated with US-guided HIFU (USgHIFU) were significantly lower than those of patients treated with MR-guided focused ultrasound surgery (MRgFUS). When the NPVR of fibroids was over 50%, the reintervention rates at 12, 36 and 60-month after HIFU were 1% (95% CI: 0.3-2), 5% (95% CI: 3-8), and 15% (95% CI: 9-20). The reintervention risk for hyper-intensity fibroids on T2WI was 3.45 times higher (95% CI: 2.7-4.39) for hypo-/iso-intensity fibroids. CONCLUSION: This meta-analysis showed that the overall reintervention rates after HIFU were acceptable and provided consultative suggestions regarding treatment alternatives for patients with fibroids. Subgroup-analysis revealed that USgHIFU, NPVR ≥ 50%, and hypo-/iso-intensity of fibroids on T2WI were significant factors in reducing reintervention. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, CRD42023456094.

Long-term re-intervention after USgHIFU and prediction of NPVR in different ages of patients with uterine fibroids.

OBJECTIVE: Long-term re-intervention after ultrasound-guided high intensity focused ultrasound (USgHIFU) ablation was reported, and the prediction of non-perfusion volume ratio (NPVR) in differently aged patients with uterine fibroids (UFs) was explored. MATERIALS AND METHODS: Patients with UFs who underwent USgHIFU ablation from January 2012 to December 2019 were enrolled and divided into < 40-year-old and ≥ 40-year-old groups. Cox regression was used to analyze the influencing factors of re-intervention rate, and receiver operating characteristic (ROC) curve was used to analyze the correlation between NPVR and re-intervention rate. RESULTS: A total of 2141 patients were enrolled, and 1558 patients were successfully followed up. The 10-year cumulative re-intervention rate was 21.9%, and the < 40-year-old group had a significantly higher rate than the ≥ 40-year-old group (30.8% vs. 19.1%, p < 0.001). NPVR was an independent risk factor in both two groups. When the NPVR reached 80.5% in the < 40-year-old group and 75.5% in the ≥ 40-year-old group, the risk of long-term re-intervention was satisfactory. CONCLUSION: The long-term outcome of USgHIFU is promising. The re-intervention rate is related to NPVR in differently aged patients. Young patients need a high NPVR to reduce re-intervention risk.

Antenatal myomectomy of huge pedunculated fibroid.

A female patient in her 20s presented at 10 weeks of pregnancy with abdominal pain. She was known to have a 17-cm fibroid a year ago, which, on repeat imaging, was found to have increased in size to 29 cm. A 12-cm increase in size over a year therefore led to concerns that it would increase in pregnancy, causing risk of thrombosis, decrease in venous return, miscarriage, fibroid torsion, fibroid necrosis, preterm labour and uterine rupture. Following a multidisciplinary team review with obstetricians, neonatologists, gynaecologists and radiologists, the patient opted to proceed with an open myomectomy at 14 weeks gestation, which was performed successfully. The pregnancy continued uneventfully until term when she delivered a healthy girl infant at 38+2 weeks via an elective caesarean section.

Comparing magnetic resonance imaging and ultrasound in the clinical evaluation of fibroids prior to uterine artery embolization.

PURPOSE: Uterine artery embolization has become established as a frontline treatment for uterine leiomyomata. In planning embolization, preprocedural imaging can further characterize pathology and anatomy, but it may also reveal coexisting diagnoses that have the potential to change clinical management. The purpose of this study is to compare the diagnostic outcomes of ultrasound and MRI performed for patients prior to undergoing embolization. METHODS: The study cohort consisted of 199 patients who underwent uterine artery embolization at a single academic institution between 2013 and 2018. Prior to embolization, all patients had an MRI confirming a leiomyomata diagnosis. Additionally, 118 patients underwent transvaginal ultrasound within five years prior to MRI. MRI findings were analyzed and, when applicable, compared to prior ultrasound impressions to assess for the incidence of new findings. The diagnoses of interest were adenomyosis, hydrosalpinx, predominantly infarcted leiomyomata, and large intracavitary leiomyomata. Data were collected from retrospective chart review and included demographics, symptomology, and imaging reports. RESULTS: 199 patients ultimately underwent embolization for treatment of MRI-confirmed leiomyomata. Of 118 patients who also had an ultrasound within five years prior to their MRI, 26 (22.0%) received a second gynecologic diagnosis based on MRI findings that was not previously seen on ultrasound. Of 81 patients who only had an MRI before embolization, 19 (23.5%) received a second gynecologic diagnosis not previously documented. The most common coexisting pathology was adenomyosis, presenting in 34 (17.1%) patients with leiomyomata, followed by large intracavitary leiomyomata (8, 4.0%), infarcted leiomyomata (7, 3.5%), and hydrosalpinx (6, 3.0%),. CONCLUSIONS: When considering uterine artery embolization for the treatment of symptomatic leiomyomata, preprocedural MRI is superior to ultrasound in detecting coexisting pathologies, including adenomyosis and hydrosalpinx. It can also better characterize leiomyomata, including identifying lesions as intracavitary or infarcted. These findings have the potential to alter clinical management or contraindicate embolization entirely.

Application of transabdominal ultrasound- and laparoscopy-guided percutaneous microwave ablation for treating uterine fibroids: 24-month follow-up outcomes.

PURPOSE: To determine the ablation efficacy of transabdominal ultrasound- and laparoscopy-guided percutaneous microwave ablation (PMWA), to investigate whether the risk of damage to adjacent organs and endometrium due to this technique can be reduced or even avoided. We also evaluated the clinical efficacy of this technique in the treatment of uterine fibroids of different sizes and at different locations over a 24-month follow-up period. METHODS: This study included 50 patients with uterine fibroids who underwent transabdominal ultrasound- and laparoscopy-guided PMWA from August 2018 to July 2020. Lesions were confirmed by pathology. The technical efficacy and complications of PMWA were assessed. The lesion diameter, lesion volume, lesion location, and contrast-enhanced ultrasound (CEUS) features before PMWA and within 24 h after PMWA were recorded. Magnetic resonance imaging (MRI) was used for follow-up at 3 and 6 months after PMWA. Transvaginal ultrasound was used for follow-up at 24 months after PMWA. RESULTS: A total of 50 patients with uterine fibroids received treatment. The median ablation rate of uterine fibroids was 97.21%. The mean lesion volume reduction rates were 32.63%, 57.26%, and 92.64% at 3, 6, and 24 months after treatment, respectively. The size and location of uterine fibroids did not significantly affect the ablation rate and the rate of lesion volume reduction. No major complication was found during and after the procedure. CONCLUSION: Transabdominal ultrasound- and laparoscopy-guided PMWA can be utilized to safely enhance the ablation rate while minimizing ablation time and avoiding harm to adjacent organs and the endometrium. This technique is applicable for treating uterine fibroids of different sizes and at varying locations. TRIAL REGISTRATION NUMBER: ChiCTR-IPR-17011910, and date of trial registration: 08/07/2017.

Differentiating Uterine Sarcoma From Atypical Leiomyoma on Preoperative Magnetic Resonance Imaging Using Logistic Regression Classifier: Added Value of Diffusion-Weighted Imaging-Based Quantitative Parameters.

OBJECTIVE: To evaluate the added value of diffusion-weighted imaging (DWI)-based quantitative parameters to distinguish uterine sarcomas from atypical leiomyomas on preoperative magnetic resonance imaging (MRI). MATERIALS AND METHODS: A total of 138 patients (age, 43.7 ± 10.3 years) with uterine sarcoma (n = 44) and atypical leiomyoma (n = 94) were retrospectively collected from four institutions. The cohort was randomly divided into training (84/138, 60.0%) and validation (54/138, 40.0%) sets. Two independent readers evaluated six qualitative MRI features and two DWI-based quantitative parameters for each index tumor. Multivariable logistic regression was used to identify the relevant qualitative MRI features. Diagnostic classifiers based on qualitative MRI features alone and in combination with DWI-based quantitative parameters were developed using a logistic regression algorithm. The diagnostic performance of the classifiers was evaluated using a cross-table analysis and calculation of the area under the receiver operating characteristic curve (AUC). RESULTS: Mean apparent diffusion coefficient value of uterine sarcoma was lower than that of atypical leiomyoma (mean ± standard deviation, 0.94 ± 0.30 10-3 mm²/s vs. 1.23 ± 0.25 10-3 mm²/s; P < 0.001), and the relative contrast ratio was higher in the uterine sarcoma (8.16 ± 2.94 vs. 4.19 ± 2.66; P < 0.001). Selected qualitative MRI features included ill-defined margin (adjusted odds ratio [aOR], 17.9; 95% confidence interval [CI], 1.41-503, P = 0.040), intratumoral hemorrhage (aOR, 27.3; 95% CI, 3.74-596, P = 0.006), and absence of T2 dark area (aOR, 83.5; 95% CI, 12.4-1916, P < 0.001). The classifier that combined qualitative MRI features and DWI-based quantitative parameters showed significantly better performance than without DWI-based parameters in the validation set (AUC, 0.92 vs. 0.78; P < 0.001). CONCLUSION: The addition of DWI-based quantitative parameters to qualitative MRI features improved the diagnostic performance of the logistic regression classifier in differentiating uterine sarcomas from atypical leiomyomas on preoperative MRI.

Circumferential esophageal leiomyoma: Management by combined robotic surgery and intraoperative endoscopy.

Leiomyoma is the most common benign tumor of the esophagus. Open thoracotomy, the traditional approach adopted for the enucleation of the esophageal leiomyoma, over the years, has been gradually replaced by video-assisted thoracoscopic surgery. However, this minimally invasive approach has limitations, such as two-dimensional vision and reduced range of motion, which have recently been overcome by technical advantages of robot-assisted surgery. In the surgical management of circumferential esophageal leiomyoma, a combined use of robotic surgery and intraoperative endoscopy may be helpful to facilitate tumor enucleation and to prevent esophageal mucosal injury during the surgical procedure.

Establishment of Noninvasive Prediction Models for the Diagnosis of Uterine Leiomyoma Subtypes.

OBJECTIVE: To establish prediction models for the diagnosis of the subtypes of uterine leiomyomas by machine learning using magnetic resonance imaging (MRI) data. METHODS: This is a prospective observational study. Ninety uterine leiomyoma samples were obtained from 51 patients who underwent surgery for uterine leiomyomas. Seventy-one samples (49 mediator complex subunit 12 [ MED12 ] mutation-positive and 22 MED12 mutation-negative leiomyomas) were assigned to the primary data set to establish prediction models. Nineteen samples (13 MED12 mutation-positive and 6 MED12 mutation-negative leiomyomas) were assigned to the unknown testing data set to validate the prediction model utility. The tumor signal intensity was quantified by seven MRI sequences (T2-weighted imaging, apparent diffusion coefficient, magnetic resonance elastography, T1 mapping, magnetization transfer contrast, T2* blood oxygenation level dependent, and arterial spin labeling) that can estimate the collagen and water contents of uterine leiomyomas. After surgery, the MED12 mutations were genotyped. These results were used to establish prediction models based on machine learning by applying support vector classification and logistic regression for the diagnosis of uterine leiomyoma subtypes. The performance of the prediction models was evaluated by cross-validation within the primary data set and then finally evaluated by external validation using the unknown testing data set. RESULTS: The signal intensities of five MRI sequences (T2-weighted imaging, apparent diffusion coefficient, T1 mapping, magnetization transfer contrast, and T2* blood oxygenation level dependent) differed significantly between the subtypes. In cross-validation within the primary data set, both machine learning models (support vector classification and logistic regression) based on the five MRI sequences were highly predictive of the subtypes (area under the curve [AUC] 0.974 and 0.988, respectively). External validation with the unknown testing data set confirmed that both models were able to predict the subtypes for all samples (AUC 1.000, 100.0% accuracy). Our prediction models with T2-weighted imaging alone also showed high accuracy to discriminate the uterine leiomyoma subtypes. CONCLUSION: We established noninvasive prediction models for the diagnosis of the subtypes of uterine leiomyomas by machine learning using MRI data.

Leiomyoma or sarcoma? MRI performance in the differential diagnosis of sonographically suspicious uterine masses.

PURPOSE: To assess the diagnostic performance of MRI in distinguishing between leiomyomas and malignant/potentially malignant mesenchymal neoplasms in patients with rapidly enlarging/sonographically suspicious uterine masses. METHODS: IRB-approved retrospective study including 88 patients (51 ± 11 years) who underwent MRI for rapidly enlarging/sonographically suspicious uterine mass at our Institution between January 2016 and December 2021, followed by surgery or >12 months follow-up. Qualitative image analysis was independently performed by 2 radiologists and included lesion's margins (sharp/irregular), architecture (homogeneous/inhomogeneous), presence of endometrial infiltration (yes/no), necrotic areas (yes/no), hemorrhagic areas (yes/no), predominant signal intensity on T1-WI, T2-WI, CE T1-WI, DWI, and ADC map. The same radiologists performed quantitative image analysis in consensus, which included lesion's maximum diameter, lesion/myometrium signal intensity ratio on T2-WI and CE T1-weighted images, lesion/endometrium signal intensity ratio on DWI and ADC map and necrosis percentage. Lesions were classified as benign or malignant. Imaging findings were compared with pathology and/or follow-up. RESULTS: After surgery (52/88 patients) or follow-up (36/88 patients, 33 ± 20 months), 83/88 (94.3%) lesions were classified as benign and 5/88 (5.7%) as malignant/potentially malignant. Presence of necrotic areas, high necrosis percentage, hyperintensity on DWI and high lesion/endometrium DWI signal intensity ratio were significantly associated with malignant/potentially malignant lesions (p = 0.027, 0.002, 0.008 and 0.015, respectively). The two readers identified malignant/potentially malignant lesions with 95.5% accuracy, 80.0% sensitivity, 96.4% specificity, 57.1 % PPV, 93.3% NPV. CONCLUSION: MRI has high accuracy in identifying malignant/potentially malignant myometrial masses. In everyday practice, however, MRI positive predictive value is relatively low given the low pre-test malignancy probability.

A Fully Electronically Steerable Therapeutic Ultrasound Phased Array With MR-Guidance.

Recently, MRI-guided focused ultrasound (FUS) has shown great promise in treating various conditions non-invasively. OBJECTIVE: The focus of this article is to introduce an MRI-guided FUS device, which can provide full electronic steering range without mechanical movement and with low near-field heating. A pilot study was conducted in order to investigate the feasibility, and safety of the device in a large animal model and a pilot clinical trial. METHODS: A flat, fully steerable FUS phased array with 4096 elements was designed and manufactured to be compatible with an MR scanner. Pre-clinical experiments were carried out for testing the accuracy of the focus at different steering angles as well as evaluating the ablation efficiency using MR thermometry. Eleven patients with uterine fibroids were treated in the pilot clinical trial. RESULTS: Pre-clinical results showed successful ablation at various steering angles with reasonable targeting accuracy and no off-target heating. During the pilot clinical study, effective fibroid ablation was achieved with significant symptom reduction observed over time. In general, the treatment results showed the system to be effective in ablating deep tissue volumes. The device was successful at efficiently ablating large volumes with minimal near-field heating and eliminating the need for mechanical translation. CONCLUSIONS: Being capable of providing high acoustic power, full electronic steering range in 3D for large volume ablations, this device can provide a safe and efficient treatment option as an outpatient procedure for uterine fibroids and other pelvic and abdominal tumors.