Ultrasound Surgery Of Uterine Fibroids Research Articles

Focused Ultrasound Surgery for Uterine Fibroids: Potential Impact on Fertility and Pregnancy Outcome - A Review

Uterine fibroids are a common gynecological disorder affecting a large number of infertile women. Their pregnancy outcomes may also be poor because of complications such as miscarriage, preterm labor, obstructed labor, or postpartum bleeding. Myomectomy was traditionally used to enhance women’s reproductive ability or reduce the above complications. However, operative myomectomy, either laparoscopic or open approach, may cause operative morbidity and raise hysterectomy risks. After myomectomy, women would also require a Caesarean section because of uterine ruptures’ risks. High Intensity Focused Ultrasound ablation (Focused Ultrasound Surgery - FUS) is currently increasingly used as a new technology to treat fibroids. Therefore, the impact of HIFU ablation on patients’ fertility and pregnancy outcomes has become a topic of interest. This paper reviewed the currently existing but limited evidence of this issue in the literature. It showed that USgHIFU/MRgFUS treatment for fibroids could be a safe alternative to myomectomy or UAE for women who wish to have babies. It also appears that FUS treatment can shorten the treatment to pregnancy interval after FUS ablation. Given the large number of women developing fibroids before childbearing, addressing this important issue in a large clinical trial is critical.

MedGA: A novel evolutionary method for image enhancement in medical imaging systems

Medical imaging systems often require the application of image enhancement techniques to help physicians in anomaly/abnormality detection and diagnosis, as well as to improve the quality of images that undergo automated image processing. In this work we introduce MedGA, a novel image enhancement method based on Genetic Algorithms that is able to improve the appearance and the visual quality of images characterized by a bimodal gray level intensity histogram, by strengthening their two underlying sub-distributions. MedGA can be exploited as a pre-processing step for the enhancement of images with a nearly bimodal histogram distribution, to improve the results achieved by downstream image processing techniques. As a case study, we use MedGA as a clinical expert system for contrast-enhanced Magnetic Resonance image analysis, considering Magnetic Resonance guided Focused Ultrasound Surgery for uterine fibroids. The performances of MedGA are quantitatively evaluated by means of various image enhancement metrics, and compared against the conventional state-of-the-art image enhancement techniques, namely, histogram equalization, bi-histogram equalization, encoding and decoding Gamma transformations, and sigmoid transformations. We show that MedGA considerably outperforms the other approaches in terms of signal and perceived image quality, while preserving the input mean brightness. MedGA may have a significant impact in real healthcare environments, representing an intelligent solution for Clinical Decision Support Systems in radiology practice for image enhancement, to visually assist physicians during their interactive decision-making tasks, as well as for the improvement of downstream automated processing pipelines in clinically useful measurements.

Adverse events of focused ultrasound surgery for uterine fibroids and adenomyosis

Adverse events of focused ultrasound surgery for uterine fibroids and adenomyosis

Scaled signal intensity of uterine fibroids based on T2-weighted MR images: a potential objective method to determine the suitability for magnetic resonance-guided focused ultrasound surgery of uterine fibroids.

Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) is a non-invasive method to treat uterine fibroids. To help determine the patient suitability for MRgFUS, we propose a new objective measure: the scaled signal intensity (SSI) of uterine fibroids in T2 weighted MR images (T2WI). Forty three uterine fibroids in 40 premenopausal women were included in this retrospective study. SSI of each fibroid was measured from the screening T2WI by standardizing its mean signal intensity to a 0-100 scale, using reference intensities of rectus abdominis muscle (0) and subcutaneous fat (100). Correlation between the SSI and the non-perfused volume (NPV) ratio (a measure for treatment success) was calculated. Pre-treatment SSI showed a significant inverse-correlation with post treatment NPV ratio (p < 0.05). When dichotomizing NPV ratio at 45 %, the optimal cut off value of the SSI was found to be 16.0. A fibroid with SSI value 16.0 or less can be expected to have optimal responses. The SSI of uterine fibroids in T2WI can be suggested as an objective parameter to help in patient selection for MRgFUS. • Signal intensity of fibroid in MR images predicts treatment response to MRgFUS. • Signal intensity is standardized into scaled form using adjacent tissues as references. • Fibroids with SSI less than 16.0 are expected to have optimal responses.

MRI-guided focused ultrasound surgery of uterine fibroids: evaluation of one-year outcome

Objective To evaluate the safety,feasibility and one-year outcome of magnetic resonance imaging-guided focused ultrasound surgery(MRgFUS) in treating uterine fibroids.Methods MRgFUS was carried out in 21 female patients with symptomatic uterine fibroids,which was immediately followed by T1-weighted fast spoiled gradient echo MRI scanning with the use of gadolinium-based contrast agent.The size of non-perfused area of the fibroids was measured in all patients,based on which the safety of the procedure and the ablation effect of the lesion were evaluated.Follow-up assessments were completed at one year after the treatment.The questionnaire about uterine fibroid symptoms and quality of life(UFS-QOL) was conducted,the symptoms severity score(SSS) was calculated,and the improvement of the symptoms and the occurrence of undesirable events related to the procedure were recorded.Pelvic MRI re-examination was made,and the size of the fibroids was compared with that determined before the treatment.Results A total of 23 fibroid lesions were detected in 21 patients.MRgFUS was successfully accomplished for all the 23 lesions.The mean operation time for each patient was 3 hours and 50 minutes.The mean non-perfused volume(NPV) on the treatment day was 62.86%(25%-99%).No serious adverse events occurred during the treatment.Seventeen patients completed one-year follow-up.The mean SSS was reduced to 8.27 ± 6.06(a reduction by 68.79%,P 0.05).Follow-up MRI showed that the fibroids volume was reduced by 49.60% on average(P 0.05).Conclusion As a kind of noninvasive technique,MRgFUS is a safe treatment for uterine fibroids with reliable short-term effectiveness.

Successful in vitro fertilization pregnancy following magnetic resonance‐guided focused ultrasound surgery for uterine fibroids

We describe an in vitro fertilization (IVF) pregnancy and delivery after magnetic resonance-guided focused ultrasound (MRgFUS) for a symptomatic uterine fibroid. A 45-year-old para 0 + 1, with four previous failed IVF treatments underwent MRgFUS for a single anterior wall fibroid causing intra-cavitary distortion and conceived after the first IVF cycle 10 months following the procedure. The patient received shared antenatal care. She was admitted in spontaneous labor at term but delivered by emergency cesarean section a healthy male infant. We describe the first IVF pregnancy following MRgFUS for a symptomatic fibroid.

Uncomplicated term vaginal delivery following magnetic resonance-guided focused ultrasound surgery for uterine fibroids

A 35 year-old para 1+0 underwent MRgFUS per study protocol for multiple uterine fibroids, the largest of which measured 5 cm. She conceived 10 months following the procedure. The patient was induced at 41+6 weeks and underwent a normal vaginal delivery.

Patient suitability for magnetic resonance guided focused ultrasound surgery of uterine fibroids

Objective To assess selection criteria used to determine eligibility for magnetic resonance-guided focused ultrasound surgery (MRgFUS) for the treatment of symptomatic uterine fibroids; to assess the percentage of patients suitable for MRgFUS. Study design A retrospective analysis of 144 patients seeking minimally invasive treatment options for symptomatic uterine fibroids at a single treatment center. Clinical eligibility for MRgFUS was assessed at a gynecology clinic by a Gynecology research fellow trained in the procedure and suitability was assessed by magnetic resonance imaging. Several techniques were used to mitigate against factors that are contra-indications for MRgFUS. Results 100% of patients interested in MRgFUS were deemed clinically eligible for the procedure and 74% were deemed technically suitable to proceed with treatment. Conclusions Mitigation techniques allow for less restrictive MRgFUS selection criteria for treatment for symptomatic uterine fibroids. These less restrictive criteria are expected to expand the pool of patients for whom MRgFUS is a viable treatment option for uterine fibroid symptoms.

Evaluation of referenceless thermometry in MRI‐guided focused ultrasound surgery of uterine fibroids

To clinically assess a previously described method (Rieke et.al., Magn Reson Med 2004) to produce more motion-robust MRI-based temperature images using data acquired during MRI-guided focused ultrasound surgery (MRgFUS) of uterine fibroids. The method ("referenceless thermometry") uses surface fitting in nonheated regions of individual phase images to extrapolate and then remove background phase variations that are unrelated to temperature changes. We tested this method using images from 100 sonications selected from 33 patient MRgFUS treatments. Temperature measurements and thermal dose contours estimated with the referenceless method were compared with those produced with the standard phase-difference technique. Fitting accuracy and noise level were also measured. In 92/100 sonications, the difference between the two measurements was less than 3 degrees C. The average difference in the measurements was 1.5 +/- 1.4 degrees C. Small motion artifacts were observed in the phase-difference imaging when the difference was greater than 3 degrees C. The method failed in two cases. The mean absolute error in the surface fit in baseline images corresponded to a temperature error of 0.8 +/- 1.4 degrees C. The noise level was approximately 40% lower than the phase-difference method. Thermal dose contours calculated from the two methods agreed well on average. Based on the small error when compared with the standard technique, this method appears to be adequate for temperature monitoring of MRgFUS in uterine fibroids and may prove useful for monitoring temperature changes in moving organs.

Patient selection guidelines in MR-guided focused ultrasound surgery of uterine fibroids: a pictorial guide to relevant findings in screening pelvic MRI

Uterine leiomyomas (fibroids), the most common benign tumor in women of childbearing age, can cause symptoms including dysmenorrhea, menorrhagia, urinary symptoms, pain and infertility. Hysterectomy is a common approach to treating uterine fibroids, and less invasive surgical approaches such as myomectomy and uterine artery embolization also have been shown to alleviate symptoms. Magnetic resonance-guided focused ultrasound surgery (MRgFUS) is the only totally non-invasive surgical approved method for treating uterine fibroids. In clinical trials, MRgFUS resulted in significant relief of uterine fibroid symptoms. The safe and effective use of MRgFUS is affected by fibroid type and location, position relative to adjacent anatomical structures and the presence of co-existent pelvic disease. Additionally, successful outcomes with MRgFUS have been correlated with the volume of fibroids ablated during the procedure. Thus, selection of patients in whom sufficient fibroid volumes can be treated safely using the MRgFUS system is critical for successful outcomes. The MR images in this pictorial essay provide examples of uterine fibroids for which MRgFUS should be considered and is designed to facilitate the selection of patients for whom MRgFUS is most likely to provide sustained symptom relief.

Subjective effect of magnetic resonance‐guided focused ultrasound surgery for uterine fibroids

We treated 69 patients with symptomatic uterine fibroids using a magnetic resonance-guided focused ultrasound surgery (MRgFUS) system. Our objective was to determine the clinical outcome of MRgFUS, focusing on symptom improvement, with emphasis on the time and extent of improvement. Patients who would have been otherwise offered conventional surgery were considered for eligibility. They were asked to report their symptom severities before and after treatment on the same query form. The questionnaire, given 6 months after treatment, included a question asking when the patients' symptoms started to improve. Their fibroids were classified into three types according to the signal intensity on T2-weighted magnetic resonance images: type 1, low intensity as skeletal muscle, type 2, intermediate intensity, lower than myometrium but higher than skeletal muscle; and type 3, high intensity, the same as or higher than myometrium. No severe adverse events occurred in any of the patients. Seven patients required alternative treatment after MRgFUS, with five of them having type 3 fibroids. Mean symptom scores were all reduced after MRgFUS, regardless of the symptom types. Frequent urination improved first, while heavy bleeding took longer to resolve than the other symptoms. MRgFUS is an effective and safe method for treating symptomatic uterine fibroids, especially for type 1 and type 2 fibroids. Type 3 fibroids, however, are difficult to treat using the current MRgFUS system.

MRI-Guided Focused Ultrasound Surgery for Uterine Fibroids

Given the morbidity associated with hysterectomy, less-invasive options for treating symptomatic uterine fibroids are appealing. In this

Magnetic resonance-guided focused ultrasound surgery for uterine fibroids: relationship between the therapeutic effects and signal intensity of preexisting T2-weighted magnetic resonance images

This study was undertaken to clarify the relationship between the signal intensity of T2-weighted magnetic resonance images and the therapeutic effect of magnetic resonance-guided focused ultrasound surgery (MRgFUS) on uterine fibroids. Ninety-five fibroids in 63 patients were classified into 3 types based on the signal intensity of T2-weighted magnetic resonance images as follows: type 1, low intensity; type 2, intermediate intensity; type 3, high intensity. The treated area ratio of MRgFUS and the volume reduction ratio 6 months after treatment were used as the indices of therapeutic effect. The treated area ratio of type 3 fibroids was the lowest among the 3 types (P < .01). The volume reduction ratio correlated with the treated area ratio (r = 0.64; P < .01). The efficacy of MRgFUS correlates with the signal intensity of T2-weighted magnetic resonance images. Type 1 and type 2 fibroids are suitable candidates for MRgFUS, whereas type 3 fibroids are not.

Magnetic resonance guided focused ultrasound surgery of uterine fibroids—The tissue effects of GnRH agonist pre-treatment

Objective The purpose of this study was to determine the ablative effect of magnetic resonance guided focused ultrasound (MRgFUS) on fibroid tissue following the administration of gonadotrophin releasing hormone (GnRH) agonist. Study design Fifty women with clinically symptomatic uterine fibroids were treated. Those with uterine diameter of 10 cm or greater were given 3 months pre-treatment with GnRH agonists. Data regarding number of ultrasound sonications, Joules of energy delivered and volume of thermal destruction was recorded. Results Twenty-seven subjects were given GnRH agonist therapy before MRgFUS and 23 women underwent MRgFUS without pre-treatment. All patients in both study groups completed MR guided FUS as an outpatient procedure with no device related adverse events reported. In the group of women who received GnRH agonists, the volume of ablation was significantly larger than that in the control group (0.06 cm 3 versus 0.03 cm 3, P < 0.05), per Joule of energy applied. Conclusion The use of GnRH agonists potentiates the thermal effects of MRgFUS in women undergoing treatment of uterine fibroids.

A Review of Magnetic Resonance Imaging-Guided Focused Ultrasound Surgery of Uterine Fibroids

Uterine fibroids are a significant cause of morbidity for women of reproductive age. Over the past decade, minimally invasive treatment options are becoming increasingly popular. A new, Food and Drug Administration-approved noninvasive treatment option is magnetic resonance-guided focused ultrasound surgery, which has the potential to become a treatment of choice for selected patients. We review the technical aspects of the procedure of magnetic resonance-guided focused ultrasound surgery for treatment of uterine fibroids, potential difficulties with treatment planning, and clinical trial results to date. We also describe current developments in treatment imaging and treatment optimization.