Search Results (20)

Focused ultrasound (FUS) is an emerging noninvasive technology with significant therapeutic potential across various clinical domains. FUS enables precise targeting of tissues using mechanisms like thermoablation, mechanical disruption, and neuromodulation, minimizing damage to surrounding areas. In movement disorders such as essential tremor and Parkinson’s disease, MR-guided FUS thalamotomy has demonstrated substantial tremor reduction and improved quality of life. Psychiatric applications include anterior capsulotomy for treatment-resistant obsessive-compulsive disorder and major depressive disorder, with promising symptom relief and minimal cognitive side effects. FUS also facilitates blood-brain barrier opening for drug delivery in neurological conditions like Alzheimer’s disease. Musculoskeletal applications highlight its efficacy in managing chronic pain from knee osteoarthritis and lumbar facet joint syndrome through precise thermal ablation. Additionally, FUS has shown potential in neuropathic pain management and peripheral nerve stimulation, offering innovative approaches for amputees and cancer survivors. Cognitive and neuromodulatory research underscores its ability to enhance motor function and interhemispheric cortical balance, benefiting stroke and traumatic brain injury rehabilitation. Despite these conditions frequently leading to various kinds of disabilities, no direct exploration of the possible FUS application in rehabilitation is yet available in the literature. All this considered, this review aims to discuss how FUS could be applied in rehabilitation, exploring the current status of knowledge and highlighting future directions. Full article

Image-guided drug delivery is a method for tracking drug carriers for activation in specific lesions in the body. Image guidance uses the labelling of the drug or carrier and a clinically approved imaging modality. MRI (magnetic resonance image)-guided drug delivery has been considered for focused ultrasound tumour-targeted drug release. Liposomes are labelled for MRI tracking and the confirmation of drug delivery. In this study, we prepared two lipids conjugated to Gd-DOTA that confer MR imaging properties. Two lipid conjugates to DOTA, a C₁₈ (LCA-1) and a C₁₆ (LCA-2), were synthesised. The lipids were combined at different ratios within the lipid mix, and we investigated their effects on the liposome’s T_m using DSC (differential scanning calorimetry) and on relaxivity using NMR. The results show that when different combinations of LCA-1 and LCA-2 were introduced into the liposomes, their ratio affected both thermal drug release and relaxivity. As these lipids are part of the liposomal membrane, they confer tracking ability, and their effect on relaxivity due to thermal release could enable the confirmation of liposomal drug release using MRI at clinically relevant magnetic field strengths. Full article

During magnetic-resonance-guided focused ultrasound ablation of the ventral intermediate thalamic nucleus (VIM) for essential tremor (ET) and Parkinson’s disease (PD), targeting is generally performed using a standard atlas-based stereotactic approach. The purpose of our work is to evaluate the anatomic variations in the venous vasculature of the thalamus in patients treated with MRgFUS, as a possible landmark for targeting. We retrospectively evaluated the relationship between the obtained thalamotomy lesion and the ipsilateral superior thalamic vein (STV). A total of 36 patients (25 ET and 11 PD) who underwent MRgFUS treatment were evaluated, and the STV was studied with susceptibility weighted imaging (SWI) sequences. Based on the axial SWI images, the distance between the STV and the center of the lesion at the presumed site of the VIM was measured in follow-up MRI images one month after treatment. Statistical analysis shows that there is a correlation between the STV and the presumed site of the VIM. The STV visible in SWI could be used as an additional, real-time, and patient-specific anatomical landmark for VIM identification during MR examination and just before and during FUS treatment. Full article

Purpose: To determine the best predictor of lesion volume induced by magnetic resonance (MR)-guided focused ultrasound (MRgFUS) thalamotomy in patients with tremor-dominant symptoms in Parkinson’s disease (PD) and essential tremor (ET) patients. Methods: Thirty-six neurological patients with medication-refractory tremor (n°19 PD; n°17 ET) were treated using a commercial MRgFUS brain system (Exablate Neuro 4000, Insightec) integrated with a 1.5 T MRI unit (Sigma HDxt; GE Medical System). Linear regression analysis was used to determine how the demographic, clinical, radiological (Fazekas scale), volumetric (total GM/WM/CSF volume, cortical thickness), and MRgFUS-related parameters [Skull Density Ratio (SDR), n° of transducer elements, n° of sonications, skull area, maximal energy delivered (watt), maximal power delivered (joule), maximal sonication time delivered, maximal mean temperature reached (T°C_max), accumulated thermal dose (ATD)] impact on ventral intermediate (VIM)-thalamotomy-related 3D volumetric lesions of necrosis and edema. Results: The VIM thalamotomy was clinically efficacious in improving the tremor symptoms of all the patients as measured at 1 week after treatment. Multiple regression analysis revealed that T°C_max and n° of transducer elements were the best predictors of the necrosis and edema volumes. Moreover, total WM volume also predicted the size of necrosis. Conclusions: Our study provides new insights into the clinical MRgFUS procedures that can be used to forecast brain lesion size and improve treatment outcomes. Full article

The potential improvement in sonication efficiency achieved by tilting the focused ultrasound (FUS) transducer of the transcranial MR-guided FUS system is presented. A total of 56 cases of patient treatment data were used. The relative position of the clinical FUS transducer to the patient’s head was reconstructed, and region-specific skull density and porosity were calculated based on the patient’s CT volume image. The total transmission coefficient of acoustic waves emitted from each channel was calculated. Then, the total energy penetrating the human skull—which represents the sonication efficiency—was estimated. As a result, improved sonication efficiency was by titling the FUS transducer to a more appropriate angle achieved in all 56 treatment cases. This simulation result suggests the potential improvement in transcranial-focused ultrasound treatment by simply adjusting the transducer angle. Full article

Epilepsy is one of the most common neurological diseases in both adults and children. Despite improvements in medical care, 20 to 30% of patients are still resistant to the best medical treatment. The quality of life, neurologic morbidity, and even mortality of patients are significantly impacted by medically intractable epilepsy. Nowadays, conservative therapeutic approaches consist of increasing medication dosage, changing to a different anti-seizure drug as monotherapy, and combining different antiseizure drugs using an add-on strategy. However, such measures may not be sufficient to efficiently control seizure recurrence. Resective surgery, ablative procedures and non-resective neuromodulatory (deep-brain stimulation, vagus nerve stimulation) treatments are the available treatments for these kinds of patients. However, invasive procedures may involve lengthy inpatient stays for the patients, risks of long-term neurological impairment, general anesthesia, and other possible surgery-related complications (i.e., hemorrhage or infection). In the last few years, MR-guided focused ultrasound (MRgFUS) has been proposed as an emerging treatment for neurological diseases because of technological advancements and the goal of minimally invasive neurosurgery. By outlining the current knowledge obtained from both preclinical and clinical studies and discussing the technical opportunities of this therapy for particular epileptic phenotypes, in this perspective review, we explore the various mechanisms and potential applications (thermoablation, blood-brain barrier opening for drug delivery, neuromodulation) of high- and low-intensity ultrasound, highlighting possible novel strategies to treat drug-resistant epileptic patients who are not eligible or do not accept currently established surgical approaches. Taken together, the available studies support a possible role for lesional treatment over the anterior thalamus with high-intensity ultrasound and neuromodulation of the hippocampus via low-intensity ultrasound in refractory epilepsy. However, more studies, likely conceiving epilepsy as a network disorder and bridging together different scales and modalities, are required to make ultrasound delivery strategies meaningful, effective, and safe. Full article

Background: The main aim of our study involves the analysis of reasons and risk factors for perioperative treatment discontinuation in patients with symptomatic uterine fibroids (UFs) who were qualified for magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) and in whom the procedure was discontinued. Methods: The presented research included 372 women who were primarily eligible for MR-HIFU, but the procedure was interrupted. The reasons and risk factors for treatment discontinuation were analyzed. A statistical comparison of two cohorts (patients in whom the treatment was discontinued and completed) was conducted based on epidemiological factors, UF characteristics and the implementation of uterotonics. Results: The mean discontinuation rate was 18.28% (n = 68). The main reason was the malposition of the intestines (52.94% of all cases). The thermoablation of subserosal UFs was a statistically significant risk factor of perioperative treatment discontinuation (OR 4.62, CI 95% 2.04–10.56), while the therapy of intramural UFs considerably decreased the risk (OR 0.21, CI 95% 0.08–0.51). The volume of the targeted UF was negatively correlated with the risk of discontinuation (OR 0.991, CI 95% 0.986–0.996). Augmentation with oxytocin, but not misoprostol, during the procedure significantly decreased the risk of potential discontinuation (OR 0.15, CI 95% 0.045–0.387, p < 0.001). Conclusion: Although the discontinuation rate seems to be relatively low, further prospective randomized trials are needed to confirm our results. The establishment of particular eligibility criteria for the treatment is a crucial issue in this area. Resigning from the procedure in cases at a high risk of discontinuation might increase patient safety and shorten the time to introduce the most appropriate therapy. Full article

We aimed to overview the most recent data on sternal metastases from a multidisciplinary approach (diagnosis strategies, outcome, and histological reports). This narrative review based on a PubMed search (between January 2020 and 22 July 2023) using key words such as “sternal”, “manubrium”, and “metastasis” within the title and/or abstract only included original papers that specifically addressed secondary sternal spreading of cancer in adults, for a total of 48 original articles (14 studies and 34 single case reports). A prior unpublished case in point is also introduced (percutaneous incisional biopsy was used to address a 10 cm sternal tumour upon first admission on an apparently healthy male). The studies (n = 14) may be classified into one of three groups: studies addressing the incidence of bone metastases (including sternum) amid different primary cancers, such as prostate cancer (N = 122 with bone metastases, 83% of them with chest wall metastases), head and neck cancers (N = 3620, 0.8% with bone metastases, and 10.34% of this subgroup with sternum involvement); and glioblastoma (N = 92 with bone metastases, 37% of them with non-vertebral metastases, including the sternum); assessment cohorts, including breast cancer (N = 410; accuracy and sensitivity of PET/CT vs. bone scintigraphy is superior with concern to sternum spreading) and bone metastases of unknown origin (N = 83, including a subgroup with sternum metastases; some features of PET/CT help the differentiation with multiple myeloma); and cohorts with various therapeutic approaches, such as palliative arterial embolization (N = 10), thymic neuroendocrine neoplasia (1/5 detected with sternum metastases), survival rates for sternum metastases vs. non-sternum chest wall involvement (N = 87), oligo-metastatic (sternal) breast cancer (3 studies, N = 16 for all of them), oligo-metastatic head and neck cancer (N = 81), conformal radiotherapy (N = 24,215, including an analysis on sternum spreading), and EBRT followed by MR-HIFU (N = 6). Core data coming from the isolated case reports (N = 34) showed a female to male ratio of 1.6; the females’ ages were between 34 and 80 (mean of 57.28) and the males’ ages varied between 33 and 79 (average of 58.78) years. The originating tumour profile revealed that the most frequent types were mammary (N = 8, all females) and thyroid (N = 9, both women and men), followed by bladder (N = 3), lung (N = 2), and kidney (N = 2). There was also one case for each of the following: adenoid cystic carcinoma of the jaw, malignant melanoma, caecum MiNEN, a brain and an extracranial meningioma, tongue carcinoma, cholangiocarcinoma, osteosarcoma, and hepatocellular carcinoma. To our knowledge, this is the most complex and the largest analysis of prior published data within the time frame of our methods. These data open up new perspectives of this intricate, dynamic, and challenging domain of sternum metastases. Awareness is a mandatory factor since the patients may have a complex multidisciplinary medical and/or surgical background or they are admitted for the first time with this condition; thus, the convolute puzzle will start from this newly detected sternal lump. Abbreviations: N = number of patients; n = number of studies; PET/CT = positron emission tomography/computed tomography; EVRT = external beam radiotherapy; MR-HIFU = magnetic resonance-guided high-intensity focused ultrasound; MiNEN = mixed neuroendocrine-non-neuroendocrine tumour. Full article

Focused ultrasound (FUS) can be used to physiologically change or destroy tissue in a non-invasive way. A few commercial systems have clinical approval for the thermal ablation of solid tumors for the treatment of neurological diseases and palliative pain management of bone metastases. However, the thermal effects of FUS are known to lead to various biological effects, such as inhibition of repair of DNA damage, reduction in tumor hypoxia, and induction of apoptosis. Here, we studied radiosensitization as a combination therapy of FUS and RT in a xenograft mouse model using newly developed MRI-compatible FUS equipment. Xenograft tumor-bearing mice were produced by subcutaneous injection of the human prostate cancer cell line PC-3. Animals were treated with FUS in 7 T MRI at 4.8 W/cm² to reach ~45 °C and held for 30 min. The temperature was controlled via fiber optics and proton resonance frequency shift (PRF) MR thermometry in parallel. In the combination group, animals were treated with FUS followed by X-ray at a single dose of 10 Gy. The effects of FUS and RT were assessed via hematoxylin-eosin (H&E) staining. Tumor proliferation was detected by the immunohistochemistry of Ki67 and apoptosis was measured by a TUNEL assay. At 40 days follow-up, the impact of RT on cancer cells was significantly improved by FUS as demonstrated by a reduction in cell nucleoli from 189 to 237 compared to RT alone. Inhibition of tumor growth by 4.6 times was observed in vivo in the FUS + RT group (85.3%) in contrast to the tumor volume of 393% in the untreated control. Our results demonstrated the feasibility of combined MRI-guided FUS and RT for the treatment of prostate cancer in a xenograft mouse model and may provide a chance for less invasive cancer therapy through radiosensitization. Full article

Magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) is an innovative treatment for patients with painful bone metastases. The adoption of MR-HIFU will be influenced by several factors beyond its effectiveness. To identify contextual factors affecting the adoption of MR-HIFU, we conducted a group concept mapping (GCM) study in four European countries. The GCM was conducted in two phases. First, the participants brainstormed statements guided by the focus prompt “One factor that may influence the uptake of MR-HIFU in clinical practice is...”. Second, the participants sorted statements into categories and rated the statements according to their importance and changeability. To generate a concept map, multidimensional scaling and cluster analysis were conducted, and average ratings for each (cluster of) factors were calculated. Forty-five participants contributed to phase I and/or II (56% overall participation rate). The resulting concept map comprises 49 factors, organized in 12 clusters: “competitive treatments”, “physicians’ attitudes”, “alignment of resources”, “logistics and workflow”, “technical disadvantages”, “radiotherapy as first-line therapy”, “aggregating knowledge and improving awareness”, “clinical effectiveness”, “patients’ preferences”, “reimbursement”, “cost-effectiveness” and “hospital costs”. The factors identified echo those from the literature, but their relevance and interrelationship are case-specific. Besides evidence on clinical effectiveness, contextual factors from 10 other clusters should be addressed to support adoption of MR-HIFU. Full article

Magnetic resonance-guided focused ultrasound (MRgFUS), in conjunction with circulating microbubbles, is an emerging technology that can transiently enhance the permeability of the blood-brain barrier (BBB) locally and non-invasively to facilitate targeted drug delivery to the brain. In this clinical trial, the feasibility and safety of BBB modulation in the putamen were evaluated for biweekly therapeutic agent delivery in patients with Parkinson’s disease. The performance of the clinical MRgFUS system’s cavitation feedback controller for active power modulation throughout the exposures was examined. The putamen was targeted unilaterally by an ExAblate Neuro MRgFUS system operating at 220 kHz. Definity microbubbles were infused via a saline bag gravity drip at a rate of 4 µL/kg per 5 min. A cavitation emissions-based feedback controller was employed to modulate the acoustic power automatically according to prescribed target cavitation dose levels. BBB opening was measured by Gadolinium (Gd)-enhanced T1-weighted MR imaging, and the presence of potential micro-hemorrhages induced by the exposures was assessed via T2*-weighted MR imaging. A total of 12 treatment sessions were carried out across four patients, with target cavitation dose levels ranging from 0.20–0.40. BBB permeability in the targeted putamen was elevated successfully in all treatments, with a 14% ± 6% mean increase in Gd-enhanced T1-weighted MRI signal intensity relative to the untreated contralateral side. No indications of red blood cell extravasations were observed on MR imaging scans acquired one day following each treatment session. The cavitation emissions-based feedback controller was effective in modulating acoustic power levels to ensure BBB permeability enhancement while avoiding micro-hemorrhages, however, further technical advancements are warranted to improve its performance for use across a wide variety of brain diseases. Full article

MR-guided high-intensity focused ultrasound (MR-HIFU) is an effective method for treating symptomatic uterine fibroids, especially solitary lesions. The aim of our study was to compare the clinical and morphological outcomes of patients who underwent MR-HIFU due to solitary fibroid (SF) or multiple fibroids (MFs) in a prospective clinical trial. We prospectively included 21 consecutive patients with SF (10) and MF (11) eligible for MR-guided HIFU. The morphological data were assessed using mint Lesion™ for MRI. The clinical data were determined using the Uterine Fibroid Symptom and Quality of Life (UFS-QOL) questionnaire before and 6 months after treatment. Unpaired and paired Wilcoxon-test and t-tests were applied, and Pearson’s coefficient was used for correlation analysis. A p-value of 0.05 was considered statistically significant. The volume of treated fibroids significantly decreased in both the SF (mean baseline: 118.6 cm³; mean 6-month follow-up: 64.6 cm³) and MF (107.2 cm³; 55.1 cm³) groups. The UFS-QOL showed clinical symptoms significantly improved for patients in both the SF and MF groups regarding concern, activities, energy/mood, and control. The short-term outcome for the treatment of symptomatic fibroids in myomatous uterus by MR-guided HIFU is clinically similar to that of solitary fibroids. Full article

The family of painful osteocytic tumors includes osteoblastomas and osteoid osteomas—these lesions are considered benign, but they could produce a significant painful symptomatology. Usually, people affected are between 20 s and 30 s. When symptomatic, an effective treatment is mandatory for the management of these lesions to allow for a ful quality of life. The possibilities of treatment range from chirurgical en-block resection (procedure of surgical oncology aiming to remove a tumoral mass in its entirety, completely surrounded by a continuous layer of healthy tissue) to interventional approaches that, nowadays, are considered the most affordable and sustainable in terms of effectiveness, recovery after procedure, and for bone structure sparing. The main techniques used for osteoid osteomas and osteoblastomas are radio frequency ablation (RFA) and magnetic resonance-guided focused ultrasound (MRgFUS): the most important difference between these approaches is the needleless approach of MRgFUS, which further reduces the minimal invasiveness of RFA (and the related consequences) and the absence of exposure to ionizing radiation. Despite their high efficacy, a recurrence of pathology may occur due to a failure in therapy. In light of this, describing the various possibilities of follow up protocols and the imaging aspects of recurrence or incomplete treatment is mandatory. In the scenario given in the literature, many authors have tried to asses an organized follow up protocol of these patients, but many of them did not undergo periodical magnetic resonance (MR) or computerized tomography (CT) because of the lack of symptomatology. However, even if it seems that clinical evolution is central, different papers describe the protocol useful to detect eventual relapse. The aim of our manuscript is to review the various possibilities of follow-up of these patients and to bring together the most salient aspects found during the management of these osteocytic bone lesions. Full article

Magnetic resonance imaging (MRI)-guided therapy for prostate cancer (PCa) aims to reduce the treatment-associated comorbidity of existing radical treatment, including radical prostatectomy and radiotherapy. Although active surveillance has been used as a conservative method to reduce overtreatment, there is a growing demand for less morbidity and personalized (focal) treatment. The development of multiparametric MRI was of real importance in improving the detection, localization and staging of PCa. Moreover, MRI has been useful for lesion targeting within the prostate, as it is used in the guidance of prostate biopsies, by means of cognitive registration, MRI-ultrasound fusion guidance or direct in-bore MRI-guidance. With regard to PCa therapies, MRI is used for precise probe placement into the lesion and to accurately monitor the treatment in real-time. Moreover, advances in MR-compatible thermal ablation allow for noninvasive real-time temperature mapping during treatment. In this review, we present an overview of the current status of MRI-guided therapies in PCa, focusing on cryoablation, focal laser ablation, high intensity focused ultrasound and transurethral ultrasound ablation. We explain the important role of MRI in the evaluation of the completeness of the ablation and during follow-up. Finally, we will discuss the challenges and future development inherent to these new technologies. Full article

Parkinson’s disease (PD) presents varying motor and non-motor features in each patient owing to their different backgrounds, such as age, gender, genetics, and environmental factors. Furthermore, in the advanced stages, troublesome symptoms vary between patients due to motor and non-motor complications. The treatment of PD has made great progress over recent decades and has directly contributed to an improvement in patients’ quality of life, especially through the progression of advanced treatment. Deep brain stimulation, radiofrequency, MR–guided focused ultrasound, gamma knife, levodopa-carbidopa intestinal gel, and apomorphine are now used in the clinical setting for this disease. With multiple treatment options currently available for all stages of PD, we here discuss the most recent options for advanced treatment, including cell therapy in advanced PD, from the perspective of personalized medicine. Full article