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1.
Cancers (Basel) ; 15(16)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37627043

RESUMO

Machine learning (ML) models have become capable of making critical decisions on our behalf. Nevertheless, due to complexity of these models, interpreting their decisions can be challenging, and humans cannot always control them. This paper provides explanations of decisions made by ML models in diagnosing four types of posterior fossa tumors: medulloblastoma, ependymoma, pilocytic astrocytoma, and brainstem glioma. The proposed methodology involves data analysis using kernel density estimations with Gaussian distributions to examine individual MRI features, conducting an analysis on the relationships between these features, and performing a comprehensive analysis of ML model behavior. This approach offers a simple yet informative and reliable means of identifying and validating distinguishable MRI features for the diagnosis of pediatric brain tumors. By presenting a comprehensive analysis of the responses of the four pediatric tumor types to each other and to ML models in a single source, this study aims to bridge the knowledge gap in the existing literature concerning the relationship between ML and medical outcomes. The results highlight that employing a simplistic approach in the absence of very large datasets leads to significantly more pronounced and explainable outcomes, as expected. Additionally, the study also demonstrates that the pre-analysis results consistently align with the outputs of the ML models and the clinical findings reported in the existing literature.

2.
J Neuroeng Rehabil ; 19(1): 94, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002827

RESUMO

BACKGROUND: Hospital-based stroke rehabilitation for stroke survivors in developing countries may be limited by staffing ratios and length of stay that could hamper recovery potential. Thus, a home-based, gamified rehabilitation system (i.e., IntelliRehab) was tested for its ability to increase cerebral blood flow (CBF), and the secondary impact of changes on the upper limb motor function and functional outcomes. OBJECTIVE: To explore the effect of IntelliRehab on CBF in chronic stroke patients and its correlation with the upper limb motor function. METHODS: Two-dimensional pulsed Arterial Spin Labelling (2D-pASL) was used to obtain CBF images of stable, chronic stroke subjects (n = 8) over 3-months intervention period. CBF alterations were mapped, and the detected differences were marked as regions of interest. Motor functions represented by Fugl-Meyer Upper Extremity Assessment (FMA) and Stroke Impact Scale (SIS) were used to assess the primary and secondary outcomes, respectively. RESULTS: Regional CBF were significantly increased in right inferior temporal gyrus and left superior temporal white matter after 1-month (p = 0.044) and 3-months (p = 0.01) of rehabilitation, respectively. However, regional CBF in left middle fronto-orbital gyrus significantly declined after 1-month of rehabilitation (p = 0.012). Moreover, SIS-Q7 and FMA scores significantly increased after 1-month and 3-months of rehabilitation. There were no significant correlations, however, between CBF changes and upper limb motor function. CONCLUSIONS: Participants demonstrated improved motor functions, supporting the benefit of using IntelliRehab as a tool for home-based rehabilitation. However, within-participant improvements may have limited potential that suggests the need for a timely administration of IntelliRehab to get the maximum capacity of improvement.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Encéfalo/diagnóstico por imagem , Humanos , Perfusão , Projetos Piloto , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral/métodos , Sobreviventes , Resultado do Tratamento , Extremidade Superior
3.
Anticancer Res ; 40(5): 2975-2980, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366451

RESUMO

BACKGROUND/AIM: Even though advanced magnetic resonance imaging (MRI) can effectively differentiate between medulloblastoma and ependymoma, it is not readily available throughout the world. This study aimed to investigate the role of simple quantified basic MRI sequences in the differentiation between medulloblastoma and ependymoma in children. PATIENTS AND METHODS: The institutional review board approved this prospective study. The brain MRI protocol, including sagittal T1-weighted, axial T2-weighted, coronal fluid-attenuated inversion recovery, and axial T1-weighted with contrast enhancement (T1WCE) sequences, was assessed in 26 patients divided into two groups: Medulloblastoma (n=22) and ependymoma (n=4). The quantified region of interest (ROI) values of tumors and their ratios to parenchyma were compared between the two groups. Multivariate logistic regression analysis was utilized to find significant factors influencing the differential diagnosis between the two groups. A generalized estimating equation (GEE) was used to create the predictive model for the discrimination of medulloblastoma from ependymoma. RESULTS: Multivariate logistic regression analysis showed that the T2- and T1WCE-ROI values of tumors and the ratios of T1WCE-ROI values to parenchyma were the most significant factors influencing the diagnosis between these two groups. GEE produced the model: y=exn/(1+exn) with predictor xn=-8.773+0.012x1 - 0.032x2 - 13.228x3, where x1 was the T2-weighted signal intensity (SI) of tumor, x2 the T1WCE SI of tumor, and x3 the T1WCE SI ratio of tumor to parenchyma. The sensitivity, specificity, and area under the curve of the GEE model were 77.3%, 100%, and 92%, respectively. CONCLUSION: The GEE predictive model can discriminate between medulloblastoma and ependymoma clinically. Further research should be performed to validate these findings.


Assuntos
Ependimoma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Meduloblastoma/diagnóstico por imagem , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Meduloblastoma/patologia , Estudos Prospectivos
4.
Radiat Oncol J ; 38(1): 52-59, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32229809

RESUMO

PURPOSE: To evaluate and compare the feasibilities of magnetic resonance (MR) image-based planning using synthetic computed tomography (sCT) versus CT (pCT)-based planning in helical tomotherapy for prostate cancer. MATERIALS AND METHODS: A retrospective evaluation was performed in 16 patients with prostate cancer who had been treated with helical tomotherapy. MR images were acquired using a dedicated therapy sequence; sCT images were generated using magnetic resonance for calculating attenuation (MRCAT). The three-dimensional dose distribution according to sCT was recalculated using a previously optimized plan and was compared with the doses calculated using pCT. RESULTS: The mean planning target volume doses calculated by sCT and pCT differed by 0.65% ± 1.11% (p = 0.03). Three-dimensional gamma analysis at a 2%/2 mm dose difference/distance to agreement yielded a pass rate of 0.976 (range, 0.658 to 0.986). CONCLUSION: The dose distribution results obtained using tomotherapy from MR-only simulations were in good agreement with the dose distribution results from simulation CT, with mean dose differences of less than 1% for target volume and normal organs in patients with prostate cancer.

5.
Med Arch ; 74(1): 42-46, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32317834

RESUMO

INTRODUCTION: Each country has its system of the training program, but to be concordant with the world in the radiology field, the process needs to have common points or common criteria. On maintaining the integrity of intersociety collaboration in the field of radiology, it is necessary to understand each country's training program for each specialty. AIM: This retrospective study aims to compare the postgraduate thesis characteristics from various sources in the field of radiology. METHODS: This was a retrospective study evaluating data that is publicly available online and at libraries and institutional review board approval, as such, was not demanded. We selected 40 published theses from the library of Pham Ngoc Thach University of Medicine and University of Medicine and Pharmacy at Ho Chi Minh City and Hanoi Medical University in Vietnam which graduated from 2008 to 2018. Of these, there were 10 PhD, 10 specialists II, 10 master's, and 10 residency theses selected. RESULTS: A total of 40 theses were analyzed from participants with a median age of 36.5. The male/female ratio was 23/17. Most of the theses were subspecialty in diagnostic radiology (87.5%) and focused on pathological radiology (95%). Adult patients were the major objectives of the theses accounted for 87.5% with predominant materials of magnetic resonance imaging counted for 47.5%. Theses in PhD group were the largest items regarding the total number of pages as well as the number of figures, and the number of references. Nonetheless, both domestic and international publications related to all theses were truly low. CONCLUSION: The postgraduate thesis of radiology in Vietnam has many different forms but mainly focuses on diagnostic and pathological radiology with materials of magnetic resonance imaging in adults. The number of international publications regarding the thesis was very small.


Assuntos
Dissertações Acadêmicas como Assunto , Povo Asiático/estatística & dados numéricos , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Editoração/estatística & dados numéricos , Radiologia/educação , Radiologia/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Vietnã , Adulto Jovem
6.
Acta Inform Med ; 28(1): 71-74, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32210519

RESUMO

INTRODUCTION: The advancement of gender equality within radiology, a predominantly male profession, has currently been a significant concern. AIM: Therefore, in this original study, we aimed to investigate the gender disparity in Vietnamese radiological societies. METHODS: No ethical committee or institutional review board approval was needed since the data were publicly available. In this retrospective study, we evaluated the faculties of four main radiological societies in Vietnam: Vietnamese society of radiology and nuclear medicine (VSRNM, n = 67); Radiological society of Ho Chi Minh City (RSHCM, n = 25); Vietnamese society of ultrasound in medicine (VSUM, n = 29); and Vietnamese society of interventional radiology (VSIR, n = 18). RESULTS: There are significantly fewer women than men in faculties of four main radiological societies (15.1% vs. 84.9%). None of the women served as a professor and leader of any radiological societies. The women with a doctor of philosophy level are relatively low among the four main radiological societies. Also, female interventional and pediatric radiologists are seriously low among four main radiological societies. CONCLUSIONS: In Vietnamese radiological societies, gender disparities exist, especially about educational degrees and professorship positions. Future studies are essential to address the underlying roots of the gender gap and aid in the implementation of gender diversity programs and policies.

7.
Diagn Interv Radiol ; 26(3): 207-215, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32209511

RESUMO

PURPOSE: We sought to present our preliminary experience on the effectiveness and safety of magnetic resonance imaging (MRI)-guided, high-intensity focused ultrasound (HIFU) therapy using a volumetric ablation technique in the treatment of Association of Asian Nations (ASEAN) patients with symptomatic uterine leiomyomas. METHODS: This study included 33 women who underwent HIFU treatment. Tissue characteristics of leiomyomas were assessed based on T2- and T1-weighted MRI. The immediate nonperfused volume (NPV) ratio and the treatment effectiveness of MRI-guided HIFU on the basis of the degrees of volume reduction and improvement in transformed symptom severity score (SSS) were assessed. RESULTS: The median immediate NPV ratio was 89.8%. Additionally, the median acoustic sonication power and HIFU treatment durations were 150 W and 125 min, respectively. At six-month follow-up, the median leiomyoma volume had decreased from 139 mL at baseline to 84 mL and the median transformed SSS had decreased from 56.2 at baseline to 18.8. No major adverse events were observed. CONCLUSION: The preliminary results demonstrated that volumetric MRI-guided HIFU therapy for the treatment of symptomatic leiomyomas in ASEAN patients appears to be clinically acceptable with regard to treatment effectiveness and safety.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Leiomioma/terapia , Imagem por Ressonância Magnética Intervencionista/instrumentação , Imageamento por Ressonância Magnética/métodos , Neoplasias Uterinas/patologia , Adulto , Assistência ao Convalescente , Ásia/epidemiologia , Ásia/etnologia , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/efeitos adversos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Segurança , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Diagn Interv Radiol ; 25(5): 398-409, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31287428

RESUMO

High-intensity focused ultrasound (HIFU) is a minimally-invasive and non-ionizing promising technology and has been assessed for its role in the treatment of not only primary tumors but also metastatic lesions under the guidance of ultrasound or magnetic resonance imaging. Its performance is notably effective in neurologic, genitourinary, hepato-pancreato-biliary, musculoskeletal, oncologic, and other miscellaneous applications. In this article, we reviewed the emerging technology of HIFU and its clinical applications.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Neoplasias/cirurgia , Humanos , Imagem por Ressonância Magnética Intervencionista , Ultrassonografia de Intervenção
9.
Int J Hyperthermia ; 35(1): 626-636, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30307340

RESUMO

OBJECTIVE: This retrospective study aimed (1) to investigate the magnetic resonance imaging (MRI) features influencing a nonperfused volume ratio (NPVr) ≥ 90% after high-intensity focussed ultrasound (HIFU) ablation of adenomyosis, and (2) to assess the safety, which was defined in terms of adverse events (AEs) and changes in anti-Mullerian hormone (AMH) concentrations, and clinical efficacy, which was defined in terms of adenomyosis volume reduction and symptom improvement at 6 months' follow-up. METHODS: Sixty-six women who underwent HIFU treatment were divided into groups A (NPVr ≥90%; n = 26) and B (NPVr <90%, n = 40). Multivariate logistic regression analyses of MRI features were conducted to identify the potential predictors of an NPVr ≥90%. RESULTS: Generalized estimating equation (GEE) analysis was used to model the prediction of an NPVr ≥90% with four significant predictors from multivariate analyses: the thickness of the subcutaneous fat layer, adenomyosis volume, T2 signal intensity (SI) ratio of adenomyosis to myometrium, and the Ktrans ratio of adenomyosis to myometrium. Clinical efficacy was significantly greater in group A than in group B. The findings showed no serious AEs and no significant differences between AMH concentrations before and 6 months after treatment. CONCLUSIONS: The present retrospective study demonstrated that achievement of NPVr ≥90% as a measure of clinical treatment success in MRI-guided HIFU treatment of adenomyosis using multivariate analyses and a prediction model is clinically possible without compromising the safety of patients.


Assuntos
Adenomiose/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos
10.
Diagn Interv Radiol ; 24(5): 283-291, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30211682

RESUMO

Magnetic resonance imaging-guided high-intensity focused ultrasound (MRI-guided HIFU) is an effective noninvasive treatment option for symptomatic uterine fibroids. However, tissue characteristics of uterine fibroids and technical limitations can limit the patient population that can benefit from this therapy. In this article, we present our literature review focusing on the influential clinical factors that might reduce the risk of an unsuccessful MRI-guided HIFU treatment outcome of uterine fibroids.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Leiomioma/diagnóstico por imagem , Imagem por Ressonância Magnética Intervencionista/métodos , Radiologia Intervencionista/instrumentação , Feminino , Humanos , Leiomioma/terapia , Radiologia Intervencionista/estatística & dados numéricos , Risco , Resultado do Tratamento , Neoplasias Uterinas/patologia
11.
Acad Radiol ; 25(10): 1257-1269, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29525424

RESUMO

RATIONALE AND OBJECTIVES: We aimed to investigate the role of magnetic resonance imaging parameters in predicting the treatment outcome of high-intensity focused ultrasound (HIFU) ablation of uterine fibroids with a nonperfused volume (NPV) ratio of at least 90%. MATERIAL AND METHODS: A total of 120 women who underwent HIFU treatment were divided into groups 1 (n = 72) and 2 (n = 48), comprising patients with an NPV ratio of at least 90% and less than 90%, respectively. Multivariate logistic regression analyses were carried out to investigate the potential predictors of the NPV ratio of at least 90%. The NPV ratios immediately post-treatment, therapeutic efficacy at 6 months' follow-up, and safety in terms of adverse effects and changes in anti-Mullerian hormone level were assessed. RESULTS: By introducing multiple predictors obtained from multivariate analyses into a generalized estimating equation model, the results showed that the thickness of the subcutaneous fat layer in the anterior abdominal wall, peak enhancement of fibroid, time to peak of fibroid, and the ratio of area under the curve of fibroid to myometrium were statistically significant, except T2 signal intensity ratio of fibroid to myometrium, hence predicting an NPV ratio of at least 90%. No serious adverse effects and no significant difference between the anti-Mullerian hormone levels before or 6 months post-treatment were reported. CONCLUSIONS: The findings in this study suggest that the achievement of NPV ratio of at least 90% in magnetic resonance imaging-guided HIFU treatment of uterine fibroids based on prediction model appears clinically possible without compromising the safety of patients.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma/diagnóstico por imagem , Leiomioma/terapia , Imageamento por Ressonância Magnética , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/terapia , Adulto , Feminino , Humanos , Leiomioma/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Gordura Subcutânea , Resultado do Tratamento , Carga Tumoral , Neoplasias Uterinas/patologia
12.
Int J Hyperthermia ; 34(3): 306-314, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28540825

RESUMO

OBJECTIVE: To assess the relationship between magnetic resonance (MR) T1 perfusion-based classification and the outcome of MR-guided high intensity focused ultrasound treatment of adenomyosis, defined as nonperfused volume (NPV) ratio. METHODS: The adenomyosis of 31 women was classified into group A (time-signal intensity [SI] curve of adenomyosis lower than that of the myometrium) and group B (time-SI curve of adenomyosis equal to or higher than that of the myometrium) on the basis of time-SI curves on dynamic contrast enhanced (DCE) MR images acquired at screening. NPV ratios immediately after treatment and adenomyosis volume reduction ratios and symptom severity scores (SSS) at the six-month follow-up were retrospectively assessed. Univariate and multivariate analysis of pretreatment parameters conducted to assess independent factors impacting on immediate NPV ratio. All adverse effects were recorded. RESULTS: The immediate NPV ratios in groups A and B were 89.2 ± 6.7% and 42.4 ± 19.0%, respectively. At the six-month follow-up, the adenomyosis volume reduction ratios in groups A and B were 0.27 ± 0.8 and 0.04 ± 0.1, respectively, with corresponding improvements of 0.7 ± 0.18 and 0.26 ± 0.25, respectively, in the mean transformed SSS. Univariate and multivariate analysis revealed that only T1 perfusion-based classification as an independent factor associated with the outcome of MR-guided high intensity focused ultrasound treatment. No serious adverse effects were reported. CONCLUSIONS: Our novel classification method introduced in this study might be clinically beneficial in classifying adenomyosis for predicting the immediate outcome of MR-guided high intensity focused ultrasound treatment.


Assuntos
Adenomiose/diagnóstico por imagem , Adenomiose/cirurgia , Adenomiose/patologia , Adulto , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
13.
J Ther Ultrasound ; 5: 22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28824811

RESUMO

BACKGROUND: To retrospectively compare the treatment success, therapeutic efficacy, and adverse effects of magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) treatment for uterine fibroid patients with and without abdominal scars. METHODS: Seventy-six women who underwent treatment were divided into group 1 (patients with abdominal scars, which were covered with scar patches that prevents ultrasound energy from reaching the scar tissue immediately behind the patch) and group 2 (patients without abdominal scars). Non-perfused volume (NPV) ratios immediately after treatment, and fibroid volume reduction ratios and symptom severity scores (SSS) at the 6-months follow-up were assessed. All adverse effects were recorded. RESULTS: The mean NPV ratios in groups 1 and 2 were 87.0 ± 14.1% and 91.5 ± 13.3%. At the 6-months follow-up, the fibroid volume reduction ratios in groups 1 and 2 were 0.45 ± 0.27 and 0.43 ± 0.21, and the corresponding improvement in mean transformed SSS were 0.7 ± 0.39 and 0.79 ± 0.28, respectively. No serious adverse effects were reported. The minor adverse effects encountered in this study are likely related to the temperature increase in the near-field of the ultrasound beam path, which inevitably leads to skin burns, or far-field heat absorption by distant bony structures (i.e., sciatic nerve symptoms), and are typically manifested inter-procedurally and resolved shortly thereafter. CONCLUSIONS: The findings in this study suggest that the scar patch could be used safely and efficiently in MRgHIFU treatment for the patients with uterine fibroids and abdominal scars in the ultrasound beam path.

14.
Eur Radiol ; 27(12): 5299-5308, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28616725

RESUMO

OBJECTIVE: To comparatively evaluate the role of magnetic resonance (MR) T1 perfusion-based time-signal intensity (SI) curves of fibroid tissue and the myometrium in classification of fibroids for predicting treatment outcomes of high-intensity focused ultrasound (HIFU) treatment. METHODS: The fibroids of 74 women who underwent MR-HIFU treatment were classified into group A (time-SI curve of fibroid lower than that of the myometrium) and group B (time-SI curve of fibroid equal to or higher than that of the myometrium). Non-perfused volume (NPV) ratios immediately after treatment and fibroid volume reduction ratios and symptom severity scores (SSS) at the 6-month follow-up were retrospectively assessed. RESULTS: The immediate NPV ratios in groups A and B were 95.3 ± 6.3% (n = 62) and 63.8 ± 11% (n = 12), respectively. At the 6-month follow-up, the fibroid volume reduction ratios in groups A and B were 0.52 ± 0.14 (n = 50) and 0.07 ± 0.14 (n = 11), with the corresponding improvement in mean transformed SSS being 0.86 ± 0.14 and 0.19 ± 0.3, respectively. No serious adverse effects were reported. CONCLUSIONS: Our novel classification method could play an important role in classifying fibroids for predicting the immediate outcomes of HIFU treatment. KEY POINTS: • MRI is an important modality for outcome prediction in HIFU treatment • Patient selection is a significant factor for achieving high NPV ratio • NPV ratio is very strongly correlated with T1 perfusion-based classification • T1 perfusion-based classification is a strong predictor of treatment outcome.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Leiomioma/classificação , Miométrio/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , Neoplasias Uterinas/classificação , Adulto , Feminino , Humanos , Leiomioma/diagnóstico , Leiomioma/cirurgia , Imagem por Ressonância Magnética Intervencionista/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/cirurgia , Adulto Jovem
16.
J Ther Ultrasound ; 4: 27, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27822376

RESUMO

BACKGROUND: Uterine fibroids are the most common benign tumor in women, and surgical intervention is still the main fibroid treatment. Patient demands have encouraged development of less-invasive methods such as high-intensity focused ultrasound (HIFU). This study aimed to evaluate the safety and effectiveness of magnetic resonance-guided high-intensity focused ultrasound therapy using a volumetric ablation technique in the treatment of symptomatic uterine fibroids in China. METHODS: One hundred and seven patients were enrolled and treated with magnetic resonance-guided high-intensity focused ultrasound in this study. Clinical efficacy was based on the proportion of patients with fibroid shrinkage (10 % volume reduction or more compared to baseline) at 6 months post treatment as measured with magnetic resonance imaging. The quality of life and symptom outcome was assessed using the uterine fibroid symptom and quality of life questionnaire with symptom severity scoring. Safety was primarily assessed by evaluating the reported adverse events. RESULTS: Ninety nine of the 107 treated patients had fibroid shrinkage at 6 months post treatment. Resulting in an overall 93 % (95 % confidence interval 86-97 %) treatment success rate, p value <0.001; the symptom severity scoring and health-related quality of life at 6 months was statistically different from the screening symptom severity scoring at 0.05 level. Of 366 adverse events reported, there were no study procedure-related or device-related serious adverse events were in the study. CONCLUSIONS: This study demonstrated that the volumetric magnetic resonance-guided high-intensity focused ultrasound device is safe and technically effective and can be utilized in clinically efficient treatments of symptomatic uterine fibroids. TRIAL REGISTRATION: NCT01588899.

17.
J Ther Ultrasound ; 4: 20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27525101

RESUMO

BACKGROUND: Abdominal scars pose a challenge in magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) therapies, limiting patient selection and increasing the risk of skin burns. Especially, scars arising from longitudinal incisions are problematic as they usually lie medially at the lower abdomen where the ultrasound beam has to go through. Volumetric sonication has been shown to efficiently enlarge the ablated volume per sonication, but they nevertheless require more thermal energy to be deposited per sonication which increases the temperature in the near-field area located between the transducer and the target region. CASE PRESENTATION: The scar patch was used in three patients undergoing MR-HIFU ablation of fibroids using volumetric technique, one with transverse incision and the other two with longitudinal incision. No severe adverse effects were observed. The relative shrinkage of the fibroid of these patients at 6-month follow-up were 67, 78, and 59 %, respectively. CONCLUSIONS: Our preliminary experience suggests that the use of scar patch on MR-HIFU ablation of fibroids using volumetric technique provides an effective treatment option for patients who were previously excluded from MR-HIFU treatment due to the abdominal scars.

18.
Invest Radiol ; 51(1): 15-24, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26309184

RESUMO

OBJECTIVES: The aim of this study was to fit and validate screening magnetic resonance imaging (MRI)-based prediction models for assessing immediate therapeutic responses of uterine fibroids to MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation. MATERIALS AND METHODS: Informed consent from all subjects was obtained for our institutional review board-approved study. A total of 240 symptomatic uterine fibroids (mean diameter, 6.9 cm) in 152 women (mean age, 43.3 years) treated with MR-HIFU ablation were retrospectively analyzed (160 fibroids for training, 80 fibroids for validation). Screening MRI parameters (subcutaneous fat thickness [mm], x1; relative peak enhancement [%] in semiquantitative perfusion MRI, x2; T2 signal intensity ratio of fibroid to skeletal muscle, x3) were used to fit prediction models with regard to ablation efficiency (nonperfused volume/treatment cell volume, y1) and ablation quality (grade 1-5, poor to excellent, y2), respectively, using the generalized estimating equation method. Cutoff values for achievement of treatment intent (efficiency >1.0; quality grade 4/5) were determined based on receiver operating characteristic curve analysis. Prediction performances were validated by calculating positive and negative predictive values. RESULTS: Generalized estimating equation analyses yielded models of y1 = 2.2637 - 0.0415x1 - 0.0011x2 - 0.0772x3 and y2 = 6.8148 - 0.1070x1 - 0.0050x2 - 0.2163x3. Cutoff values were 1.312 for ablation efficiency (area under the curve, 0.7236; sensitivity, 0.6882; specificity, 0.6866) and 4.019 for ablation quality (0.8794; 0.7156; 0.9020). Positive and negative predictive values were 0.917 and 0.500 for ablation efficiency and 0.978 and 0.600 for ablation quality, respectively. CONCLUSIONS: Screening MRI-based prediction models for assessing immediate therapeutic responses of uterine fibroids to MR-HIFU ablation were fitted and validated, which may reduce the risk of unsuccessful treatment.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma/diagnóstico , Leiomioma/cirurgia , Imageamento por Ressonância Magnética , Cirurgia Assistida por Computador , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/cirurgia , Adulto , Feminino , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Pessoa de Meia-Idade , Modelos Teóricos , Valor Preditivo dos Testes , Estudos Retrospectivos
20.
Magn Reson Imaging ; 32(9): 1156-61, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25091628

RESUMO

Higher perfusion of uterine fibroids at baseline is recognized as cause for poor efficacy of MR-guided high intensity focused ultrasound (HIFU) ablation, and higher acoustic power has been suggested for the treatment of high-perfused areas inside uterine fibroids. However, considering the heterogeneously vascular distribution inside the uterine fibroids especially with hyper vascularity, it is not easy to choose the correct therapy acoustic power for every part inside fibroids. In our study, we presented two cases of fibroids with hyper vascularity, to show the differences between them with different outcomes. Selecting higher therapy acoustic powers to ablate high-perfused areas efficiently inside fibroids might help achieving good ablation results. Volume transfer constant (K(trans)) maps from dynamic contrast-enhanced (DCE) imaging at baseline helps visualizing perfusion state inside the fibroids and locating areas with higher-perfusion. In addition, with the help of K(trans) maps, appropriate therapy acoustic power could be selected by the result of initial test and therapy sonications at different areas with significantly different perfusion state inside fibroids.


Assuntos
Meios de Contraste , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Aumento da Imagem/métodos , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Imagem por Ressonância Magnética Intervencionista/métodos , Adulto , Feminino , Humanos , Resultado do Tratamento , Ultrassonografia
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