Publications by authors named "Roberto Blanco Sequeiros"

60 Publications

Prospective comparison of F-PSMA-1007 PET/CT, whole-body MRI and CT in primary nodal staging of unfavourable intermediate- and high-risk prostate cancer.

Eur J Nucl Med Mol Imaging 2021 Mar 13. Epub 2021 Mar 13.

Department of Urology, University of Turku and Turku University Hospital, Turku, Finland.

Purpose: To prospectively compare F-prostate-specific membrane antigen (PSMA)-1007 positron emission tomography (PET)/CT, whole-body magnetic resonance imaging (WBMRI) including diffusion-weighted imaging (DWI) and standard computed tomography (CT), in primary nodal staging of prostate cancer (PCa).

Methods: Men with newly diagnosed unfavourable intermediate- or high-risk PCa prospectively underwent F-PSMA-1007 PET/CT, WBMRI with DWI and contrast-enhanced CT within a median of 8 days. Six readers (two for each modality) independently reported pelvic lymph nodes as malignant, equivocal or benign while blinded to the other imaging modalities. Sensitivity, specificity and accuracy were reported according to optimistic (equivocal lesions interpreted as benign) and pessimistic (equivocal lesions interpreted as malignant) analyses. The reference standard diagnosis was based on multidisciplinary consensus meetings where available histopathology, clinical and follow-up data were used.

Results: Seventy-nine patients completed all the imaging modalities, except for one case of interrupted WBMRI. Thirty-one (39%) patients had pelvic lymph node metastases, which were detected in 27/31 (87%), 14/31 (45%) and 8/31 (26%) patients by F-PSMA-1007 PET/CT, WBMRI with DWI and CT, respectively (optimistic analysis). In 8/31 (26%) patients, only F-PSMA-1007 PET/CT detected malignant lymph nodes, while the other two imaging modalities were reported as negative. At the patient level, sensitivity and specificity values for F-PSMA-1007 PET/CT, WBMRI with DWI and CT in optimistic analysis were 0.87 (95%CI 0.71-0.95) and 0.98 (95%CI 0.89-1.00), 0.37 (95%CI 0.22-0.55) and 0.98 (95%CI 0.89-1.00) and 0.26 (95%CI 0.14-0.43) and 1.00 (95%CI 0.93-1.00), respectively.

Conclusion: F-PSMA-1007 PET/CT showed significantly greater sensitivity in nodal staging of primary PCa than did WBMRI with DWI or CT, while maintaining high specificity.

Clinical Trial Registration: Clinicaltrials.gov ID: NCT03537391.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00259-021-05296-1DOI Listing
March 2021

Multiparametric magnetic resonance-guided and monitored microwave ablation in liver cancer.

J Cancer Res Ther 2020 ;16(7):1625-1633

Department of Interventional MRI, Shandong Key Laboratory of Advanced Medical Imaging Technologies and Applications, Shandong Medical Imaging Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.

Purpose: The objective of our study was to prospectively evaluate the feasibility, effectiveness, and safety of 1.0T open multiparametric magnetic resonance (MR)-guided and monitored microwave ablation (MWA) of liver cancer.

Materials And Methods: Fifty-six liver lesions (12 - initial hepatocellular carcinoma, 34 - recurrent hepatocellular carcinoma, and 10 - metastatic liver cancers) in 45 patients were treated with MWA ablation using MR guidance and monitoring. The mean diameter of the liver lesions was 1.7 ± 0.9 cm (range, 0.5-4.6 cm). The 56 liver lesions were divided into 3 groups according to diameter: the <1.0 cm group (17 lesions), the 1.0-2.0 cm group (19 lesions), and the >2.0 cm group (20 lesions). Technical success, technical effectiveness, local tumor progression, procedure duration, and complications were assessed. Primary technical effectiveness was assessed 3 months after the MWA, while local tumor progression was assessed more than 3 months after the MWA. The follow-up time for assessment of treatment response ranged from 12 to 30 months (median, 23 months).

Results: The technical success rate was 100%. Primary technical effectiveness was achieved in 52/56 (92.8%) lesions. Local tumor progression was detected in three tumors after initial technical effectiveness. The median duration of the intervention per tumor was 66 min (range, 40-156 min). There were no significant differences between lesion groups in the technical success rate, primary technical effectiveness rate, or local tumor progression rate. There were no major complications following the ablation therapy.

Conclusions: 1.0T open multiparametric MR-guided and MR-monitored MWA for liver cancer is safe and feasible and decreases the risk of local tumor progression; it also provides good primary technique effectiveness rates and is especially suitable when ultrasound and CT facilitated treatments are inappropriate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/jcrt.JCRT_1024_20DOI Listing
January 2020

Feasibility of apparent diffusion coefficient in predicting the technical outcome of MR-guided high-intensity focused ultrasound treatment of uterine fibroids - a comparison with the Funaki classification.

Int J Hyperthermia 2021 ;38(1):85-94

Department of Radiology, Turku University Hospital, Turku, Finland.

Purpose: To investigate the feasibility of using an apparent diffusion coefficient (ADC) classification in predicting the technical outcome of magnetic resonance imaging-guided high-intensity focused ultrasound (MRgHIFU) treatment of symptomatic uterine fibroids and to compare it to the Funaki classification.

Materials And Methods: Forty-two patients with forty-eight uterine fibroids underwent diffusion-weighted imaging (DWI) before MRgHIFU treatment. The DW images were acquired with five different b-values. Correlations between ADC values and treatment parameters were assessed. Optimal ADC cutoff values were determined to predict technical outcomes, that is, nonperfused volume ratios (NPVr) such that three classification groups were created (NPVr of <30%, 30-80%, or >80%). Results were compared to the Funaki classification using receiver-operating-characteristic (ROC) curve analysis, with statistical significance being tested with the Chi-square test.

Results: A statistically significant negative correlation (Spearman's = -0.31, -value < 0.05) was detected between ADC values and NPV ratios. ROC curve analysis indicated that optimal ADC cutoff values of 980 × 10mm/s (NPVr > 80%) and 1800 × 10mm/s (NPVr < 30%) made it possible to classify fibroids into three groups: ADC I (NPVr > 80%), ADC II (NPVr 30-80%) and ADC III (NPVr < 30%). Analysis of the whole model area under the curve resulted in values of 0.79 for the ADC classification (-value = 0.0007) and 0.62 for the Funaki classification (-value = 0.0527).

Conclusions: Lower ADC values prior to treatment correlate with higher NPV ratios. The ADC classification seems to be able to predict the NPV ratio and may even outperform the Funaki classification. Based on these results DWI and ADC maps should be included in the MRI screening protocol.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/02656736.2021.1874545DOI Listing
January 2021

Acute and subacute prostate MRI findings after MRI-guided transurethral ultrasound ablation of prostate cancer.

Acta Radiol 2020 Nov 28:284185120976931. Epub 2020 Nov 28.

Department of Radiology, Turku University Hospital, Turku, Finland.

Background: Magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (TULSA) is an emerging method for treatment of localized prostate cancer (PCa). TULSA-related subacute MRI findings have not been previously characterized.

Purpose: To evaluate acute and subacute MRI findings after TULSA treatment in a treat-and-resect setting.

Material And Methods: Six men with newly diagnosed MRI-visible and biopsy-concordant clinically significant PCa were enrolled and completed the study. Eight lesions classified as PI-RADS 3-5 were focally ablated using TULSA. One- and three-week follow-up MRI scans were performed between TULSA and robot-assisted laparoscopic prostatectomy.

Results: TULSA-related hemorrhage was detected as a subtle T1 hyperintensity and more apparent T2 hypointensity in the MRI. Both prostate volume and non-perfused volume (NPV) markedly increased after TULSA at one week and three weeks after treatment, respectively. Lesion apparent diffusion coefficient values increased one week after treatment and decreased nearing the baseline values at the three-week MRI follow-up.

Conclusion: The optimal timing of MRI follow-up seems to be at the earliest at three weeks after treatment, when the post-procedural edema has decreased and the NPV has matured. Diffusion-weighted imaging has little or no added diagnostic value in the subacute setting.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/0284185120976931DOI Listing
November 2020

Oxytocin selectively reduces blood flow in uterine fibroids without an effect on myometrial blood flow: a dynamic contrast enhanced MRI evaluation.

Int J Hyperthermia 2020 ;37(1):1293-1300

Department of Obstetrics and Gynecology, Turku University Hospital, Turku, Finland.

Introduction: Uterine fibroids are the most common benign neoplasms in women. The administration of intravenous oxytocin is known to increase the efficacy of a non-invasive thermal ablation method (MR-HIFU) for treating fibroids. However, it is not known whether this phenomenon is caused by the effect of the oxytocin on the myometrium or the fibroid itself. The objective of this study was to evaluate the influence of oxytocin on the blood flow of fibroids, myometrium and skeletal muscle using a quantitative perfusion MRI technique.

Materials And Methods: 17 premenopausal women with fibroids considered to be treated with MR-HIFU and 11 women with no fibroids were enrolled in the study. An extended MRI protocol of the pelvis was acquired for each subject. Later another MRI scan was performed with continuous intravenous infusion of oxytocin. The effect of oxytocin was analyzed from quantitative perfusion imaging. The study was registered in clinicaltrials.gov NCT03937401.

Results: Oxytocin decreased the blood flow of each fibroid; the median blood flow of fibroid was 39.9 ml/100 g tissue/min without and 3.5 mL/100 g/min with oxytocin ( ≤ 0.0001). Oxytocin did not affect the blood flow of the myometrium in either group. Oxytocin increased the blood flow of the skeletal muscle in both groups ( = 0.04).

Conclusion: Oxytocin is effective in decreasing the blood flow in fibroids while having minor or no effect on the blood flow of normal myometrium. Routine use of oxytocin in HIFU therapy may make the therapy suitable to a larger group of women in a safe manner.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/02656736.2020.1846792DOI Listing
January 2020

Palliative MRI-guided transurethral ultrasound ablation for symptomatic locally advanced prostate cancer.

Scand J Urol 2020 Dec 8;54(6):481-486. Epub 2020 Sep 8.

Department of Urology, University of Turku and Turku University Hospital, Turku, Finland.

Purpose: Locally advanced prostate cancer can cause bladder outlet obstruction, gross hematuria and frequent hospitalization. While these complications are commonly treated by palliative transurethral resection of the prostate, the improvement is often insufficient. The purpose of this study was to evaluate the safety and feasibility of MRI-guided transurethral ultrasound ablation as an alternative palliative treatment option (pTULSA) for men suffering from symptomatic locally advanced prostate cancer.

Methods: This prospective, phase one study included 10 men in need of palliative surgical intervention due to urinary retention and gross hematuria caused by locally advanced prostate cancer. Patients were followed for 1 year at 3-month intervals. Time without catheter, time without hematuria, reduction in hospitalization time, and adverse events were measured.

Results: Ten patients with locally advanced prostate cancer were enrolled, all having continuous catheterization due to urinary retention and nine had gross hematuria before treatment. At 1 week post-pTULSA five patients were catheter-free. At last follow-up catheter-free and gross hematuria-free rates were 70% and 100%, respectively. Average hospitalization time from local complications reduced from 7.3 to 1.4 days in the 6 months before and after pTULSA. No > Grade 2 treatment related adverse events were reported, with all five being urinary tract infections.

Conclusions: pTULSA appears safe and feasible for palliative ablation of locally advanced prostate cancer. The therapy seems to accomplish long-term hematuria control, can relieve bladder outlet obstruction in selected patients, and seems to reduce the burden of hospitalization due to local complications. NCT03350529.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/21681805.2020.1814857DOI Listing
December 2020

A Prospective Comparison of F-prostate-specific Membrane Antigen-1007 Positron Emission Tomography Computed Tomography, Whole-body 1.5 T Magnetic Resonance Imaging with Diffusion-weighted Imaging, and Single-photon Emission Computed Tomography/Computed Tomography with Traditional Imaging in Primary Distant Metastasis Staging of Prostate Cancer (PROSTAGE).

Eur Urol Oncol 2020 Jul 13. Epub 2020 Jul 13.

Department of Urology, University of Turku and Turku University Hospital, Turku, Finland.

Background: Computed tomography (CT) and bone scintigraphy (BS) are the imaging modalities currently used for distant metastasis staging of prostate cancer (PCa).

Objective: To compare standard staging modalities with newer and potentially more accurate imaging modalities.

Design, Setting, And Participants: This prospective, single-centre trial (NCT03537391) enrolled 80 patients with newly diagnosed high-risk PCa (International Society of Urological Pathology grade group ≥3 and/or prostate-specific antigen [PSA] ≥20 and/or cT ≥ T3; March 2018-June 2019) to undergo primary metastasis staging with two standard and three advanced imaging modalities.

Outcome Measurements And Statistical Analysis: The participants underwent the following five imaging examinations within 2 wk of enrolment and without a prespecified sequence: BS, CT, Tc-hydroxymethylene diphosphonate (Tc-HMDP) single-photon emission computed tomography (SPECT)-CT, 1.5 T whole-body magnetic resonance imaging (WBMRI) using diffusion-weighted imaging, and F-prostate-specific membrane antigen-1007 (F-PSMA-1007) positron emission tomography(PET)-CT. Each modality was reviewed by two independent experts blinded to the results of the prior studies, who classified lesions as benign, equivocal, or malignant. Pessimistic and optimistic analyses were performed to resolve each equivocal diagnosis. The reference standard diagnosis was defined using all available information accrued during at least 12 mo of clinical follow-up. Patients with equivocal reference standard diagnoses underwent MRI and/or CT to search for the development of anatomical correspondence. PSMA PET-avid lesions without histopathological verification were rated to be malignant only if there was a corresponding anatomical finding suspicious for malignancy at the primary or follow-up imaging.

Results And Limitations: Seventy-nine men underwent all imaging modalities except for one case of interrupted MRI. The median interval per patient between the first and the last imaging study was 8 d (interquartile range [IQR]: 6-9). The mean age was 70 yr (standard deviation: 7) and median PSA 12 ng/mL (IQR:7-23). The median follow-up was 435 d (IQR: 378-557). Metastatic disease was detected in 20 (25%) patients. The imaging modality F-PSMA-1007 PET-CT had superior sensitivity and highest inter-reader agreement. The area under the receiver-operating characteristic curve (AUC) values for bone metastasis detection with PSMA PET-CT were 0.90 (95% confidence interval [CI]: 0.85-0.95) and 0.91 (95% CI: 0.87-0.96) for readers 1 and 2, respectively, while the AUC values for BS, CT, SPECT-CT, and WBMRI were 0.71 (95% CI: 0.58-0.84) and 0.8 (95% CI: 0.67-0.92), 0.53 (95% CI: 0.39-0.67) and 0.66 (95% CI: 0.54-0.77), 0.77 (95% CI: 0.65-0.89) and 0.75 (95% CI: 0.62-0.88), and 0.85 (95% CI: 0.74-0.96) and 0.67 (95% CI: 0.54-0.80), respectively, for the other four pairs of readers. The imaging method F-PSMA-1007 PET-CT detected metastatic disease in 11/20 patients in whom standard imaging was negative and influenced clinical decision making in 14/79 (18%) patients. In 12/79 cases, false positive bone disease was reported only by PSMA PET-CT. Limitations included a nonrandomised study setting and few histopathologically validated suspicious lesions.

Conclusions: Despite the risk of false positive bone lesions, F-PSMA-1007 PET-CT outperformed all other imaging methods studied for the detection of primary distant metastasis in high-risk PCa.

Patient Summary: In this report, we compared the diagnostic performance of conventional and advanced imaging. It was found that F-prostate-specific membrane antigen-1007 positron emission tomography/computed tomography (F-PSMA-1007 PET-CT) was superior to the other imaging modalities studied for the detection of distant metastasis at the time of initial diagnosis of high-risk prostate cancer. PSMA PET-CT also appears to detect some nonmetastatic bone lesions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.euo.2020.06.012DOI Listing
July 2020

A novel three-dimensional template combined with MR-guided I brachytherapy for recurrent glioblastoma.

Radiat Oncol 2020 Jun 8;15(1):146. Epub 2020 Jun 8.

Department of Interventional MRI, Shandong Medical Imaging Research Institute, Cheeloo College of Medicine, Shandong University, Shandong Key Laboratory of Advanced Medical Imaging Technology and Application, Jinan, Shandong, People's Republic of China.

Background: At present, the treatment of recurrent glioblastoma is extremely challenging. In this study, we used a novel three-dimensional non-coplanar template (3DNPT) combined with open MR to guide I seed implantation for recurrent glioblastoma. The aim of this study was to evaluate the feasibility, accuracy, and effectiveness of this technique.

Methods: Twenty-four patients of recurrent glioblastoma underwent 3DNPT with open MR-guided I brachytherapy from August 2017 to January 2019. Preoperative treatment plan and 3DNPT were made according to enhanced isovoxel T1-weighted MR images. I seeds were implanted using 3DNPT and 1.0-T open MR imaging guidance. Dosimetry verification was performed after brachytherapy based on postoperative CT/MR fusion images. Preoperative and postoperative dosimetry parameters of D90, V100, V200, conformity index (CI), external index (EI) were compared. The objective response rate (ORR) at 6 months and 1-year survival rate were calculated. Median overall survival (OS) measured from the date of brachytherapy was estimated by Kaplan-Meier method.

Results: There were no significant differences between preoperative and postoperative dosimetry parameters of D90, V100, V200, CI, EI (P > 0.05). The ORR at 6 months was 75.0%. The 1-year survival rate was 58.3%. Median OS was 12.9 months. One case of small amount of epidural hemorrhage occurred during the procedure. There were 3 cases of symptomatic brain edema after brachytherapy treatment, including grade three toxicity in 1 case and grade two toxicity in 2 cases. The three patients were treated with corticosteroid for 2 to 4 weeks. The clinical symptoms related to brain edema were significantly alleviated thereafter.

Conclusions: 3DNPT combined with open MR-guided I brachytherapy for circumscribed recurrent glioblastoma is feasible, effective, and with low risk of complications. Postoperative dosimetry matched the preoperative treatment plan. The described method can be used as a novel implantation technique for I brachytherapy in the treatment of recurrent gliomas.

Trial Registration: The study was approved by the Institutional Review Board of Shandong Provincial Hospital Affiliated to Shandong University (NSFC:NO.2017-058), registered 1st July 2017.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13014-020-01586-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7282063PMC
June 2020

High-Intensity Focused Ultrasound Therapy in the Uterine Fibroid: A Clinical Case Study of Poor Heating Efficacy.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:2500-2503

A clinical case study of high-intensity focused ultrasound (HIFU) treatment in the uterine fibroid was conducted. During the therapy, poor heating efficacy was observed which could be attributed to several factors such as the local perfusion rate, patient-specific anatomy or changes in acoustic parameters of the ultrasound field. In order to determine the cause of the diminished heating, perfusion analyses and ultrasound simulations were conducted using the magnetic resonance imaging (MRI) data from the treatment. The perfusion analysis showed high local perfusion rate in the myoma (301.0 ± 25.6 mL/100 g/min) compared to the surrounding myometrium (233.8 ± 16.2 mL/100 g/min). The ultrasound simulations did not show large differences in the focal point shape or the acoustic pressure (2.07 ± 0.06 MPa) when tilting the transducer. However, a small shift (-2.2 ± 1.3 mm) in the axial location of the focal point was observed. The main causes for the diminished heating were likely the high local perfusion and ultrasound attenuation due to the deep location of the myoma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/EMBC.2019.8857147DOI Listing
July 2019

Feasibility of MRI-guided transurethral ultrasound for lesion-targeted ablation of prostate cancer.

Scand J Urol 2019 Oct 26;53(5):295-302. Epub 2019 Sep 26.

Department of Urology, Turku University Hospital, Turku, Finland.

MRI-guided transurethral ultrasound ablation (TULSA) has been evaluated for organ-confined prostate cancer (PCa). The purpose of this study was to assess the safety and toxicity, accuracy and short-term evolution of cell-death after lesion-targeted TULSA. This prospective, registered, Phase-I treat-and-3-week-resect-study enrolled six patients with MRI-visible-biopsy-concordant PCa. Lesions were targeted using TULSA with radical intent, except near neurovascular bundles (NVB). Robot-assisted-laparoscopic-prostatectomy (RALP) was performed at 3 weeks. Post-TULSA assessments included MRI (1 and 3 weeks), adverse events and quality-of-life (QoL) to 3 weeks, followed by RALP and whole-mount-histology. Treatment accuracy and demarcation of thermal injury were assessed using MRI and histology. Six patients (median age = 70 years, prostate volume = 60 ml, PSA = 8.9 ng/ml) with eight biopsy-confirmed MRI-lesions (PIRADS ≥3) were TULSA-treated without complications (median sonication and MRI-times of 17 and 117 min). Foley-catheter removal was uneventful at 2-3 days. Compared to baseline, no differences in QoL were noted at 3 weeks. During follow-up, MRI-derived non-perfused-volume covered ablated targets and increased 36% by 3 weeks, correlating with necrosis-area on histology. Mean histological demarcation between complete necrosis and outer-limit-of-thermal-injury was 1.7 ± 0.4 mm. Coagulation necrosis extended to capsule except near NVB, where 3 mm safety-margins were applied. RALPs were uncomplicated and histopathology showed no viable cancer within the ablated tumor-containing target. Lesion-targeted TULSA demonstrates accurate and safe ablation of PCa. A significant increase of post-TULSA non-perfused-volume was observed during 3 weeks follow-up concordant with necrosis on histology. TULSA achieved coagulation necrosis of all targeted tissues. A limitation of this treat-and-resect-study-design was conservative treatment near NVB in patients scheduled for RALP.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/21681805.2019.1660707DOI Listing
October 2019

Clinical evaluation of in silico planning and real-time simulation of hepatic radiofrequency ablation (ClinicIMPPACT Trial).

Eur Radiol 2020 Feb 30;30(2):934-942. Epub 2019 Aug 30.

Department of Diagnostic and Interventional Radiology, University of Leipzig Medical Center, Liebigstraße 20, 04103, Leipzig, Germany.

Objectives: To evaluate the accuracy and clinical integrability of a comprehensive simulation tool to plan and predict radiofrequency ablation (RFA) zones in liver tumors.

Methods: Forty-five patients with 51 malignant hepatic lesions of different origins were included in a prospective multicenter trial. Prior to CT-guided RFA, all patients underwent multiphase CT which included acquisitions for the assessment of liver perfusion. These data were used to generate a 3D model of the liver. The intra-procedural position of the RFA probe was determined by CT and semi-automatically registered to the 3D model. Size and shape of the simulated ablation zones were compared with those of the thermal ablation zones segmented in contrast-enhanced CT images 1 month after RFA; procedure time was compared with a historical control group.

Results: Simulated and segmented ablation zone volumes showed a significant correlation (ρ = 0.59, p < 0.0001) and no significant bias (Wilcoxon's Z = 0.68, p = 0.25). Representative measures of ablation zone comparison were as follows: average surface deviation (absolute average error, AAE) with 3.4 ± 1.7 mm, Dice similarity coefficient 0.62 ± 0.14, sensitivity 0.70 ± 0.21, and positive predictive value 0.66 ± 0. There was a moderate positive correlation between AAE and duration of the ablation (∆t; r = 0.37, p = 0.008). After adjustments for inter-individual differences in ∆t, liver perfusion, and prior transarterial chemoembolization procedures, ∆t was an independent predictor of AAE (ß = 0.03 mm/min, p = 0.01). Compared with a historical control group, the simulation added 3.5 ± 1.9 min to the procedure.

Conclusion: The validated simulation tool showed acceptable speed and accuracy in predicting the size and shape of hepatic RFA ablation zones. Further randomized controlled trials are needed to evaluate to what extent this tool might improve patient outcomes.

Key Points: • More reliable, patient-specific intra-procedural estimation of the induced RFA ablation zones in the liver may lead to better planning of the safety margins around tumors. • Dedicated real-time simulation software to predict RFA-induced ablation zones in patients with liver malignancies has shown acceptable agreement with the follow-up results in a first prospective multicenter trial suggesting a randomized controlled clinical trial to evaluate potential outcome benefit for patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00330-019-06411-5DOI Listing
February 2020

Histopathological evaluation of prostate specimens after thermal ablation may be confounded by the presence of thermally-fixed cells.

Int J Hyperthermia 2019 ;36(1):915-925

Department of Urology, Turku University Hospital , Turku , Finland.

Prostate cancer can be eradicated with heat exposure. However, high and rapid temperature elevations may cause thermofixation giving the appearance of viable tissue. The purpose was to characterize the immunoprofile and evaluate the viability of prostate regions with suspected thermofixation. A prospective, ethics-approved and registered study (NCT03350529) enrolled six patients with MRI-visible, biopsy-concordant prostate cancer to undergo lesion-targeted MRI-guided transurethral ultrasound ablation (TULSA) followed by radical prostatectomy at 3 weeks, to evaluate the accuracy and efficacy of TULSA with whole-mount histology as a reference standard. If ambiguity about complete necrosis within the ablated region remained after hematoxylin-eosin staining, viability was assessed by immunohistochemistry. Treatment day MRI-thermometry and 3-week contrast-enhanced MRI post-TULSA were examined to assess ablation success and correlation with histopathology. One patient presented with an apparently viable subregion inside the ablated area, surrounded by necrosis on H&E staining, located where temperature was highest on MRI-thermometry and tissues completely devascularized on MRI. Immunoprofile of the apparently viable tissue revealed changes in staining patterns suggesting thermofixation; the most significant evidence was the negative cytokeratin 8 staining detected with Cam5.2 antibody. A comprehensive literature review supports these observations of thermofixation with similar findings in prostate and other tissues. Thermally-fixed cells can sustain morphology on H&E staining. Misinterpretation of treatment failure may occur, if this phenomenon is not recognized and immunohistochemistry performed. Based on the previous literature and the current study, Cam5.2 staining for cytokeratin 8 appears to be a practical and reliable tool for distinguishing thermally-fixed from viable cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/02656736.2019.1652773DOI Listing
January 2020

Comprehensive feature selection for classifying the treatment outcome of high-intensity ultrasound therapy in uterine fibroids.

Sci Rep 2019 07 29;9(1):10907. Epub 2019 Jul 29.

Department of Radiology, Turku University Hospital, Kiinamyllynkatu 4-8, 20521, Turku, Finland.

The study aim was to utilise multiple feature selection methods in order to select the most important parameters from clinical patient data for high-intensity focused ultrasound (HIFU) treatment outcome classification in uterine fibroids. The study was retrospective using patient data from 66 HIFU treatments with 89 uterine fibroids. A total of 39 features were extracted from the patient data and 14 different filter-based feature selection methods were used to select the most informative features. The selected features were then used in a support vector classification (SVC) model to evaluate the performance of these parameters in predicting HIFU therapy outcome. The therapy outcome was defined as non-perfused volume (NPV) ratio in three classes: <30%, 30-80% or >80%. The ten most highly ranked features in order were: fibroid diameter, subcutaneous fat thickness, fibroid volume, fibroid distance, Funaki type I, fundus location, gravidity, Funaki type III, submucosal fibroid type and urinary symptoms. The maximum F1-micro classification score was 0.63 using the top ten features from Mutual Information Maximisation (MIM) and Joint Mutual Information (JMI) feature selection methods. Classification performance of HIFU therapy outcome prediction in uterine fibroids is highly dependent on the chosen feature set which should be determined prior using different classifiers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-019-47484-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6662821PMC
July 2019

Interventional magnetic resonance imaging as a diagnostic and therapeutic method in treating acute pediatric atlantoaxial rotatory subluxation.

Exp Ther Med 2019 Jul 9;18(1):18-24. Epub 2019 May 9.

Department of Children and Adolescents, Oulu University Hospital, Oulu 90220, Finland.

Atlantoaxial rotatory subluxation or fixation (AARF) is a rare condition, usually occurring in pediatric patients. It mimics benign torticollis but may result in permanent disability or death. The condition requires prompt diagnosis by thorough examination to avoid any treatment delays. Spiral computed tomography (CT) with three-dimensional reconstruction CT is recommended for identifying incongruence between C1 and C2 vertebrae, and magnetic resonance imaging (MRI) may be performed to exclude ligamentous injuries. In addition to static imaging, dynamic CT involves the reduction between C1 and C2 being confirmed using CT with the head turned maximally to the left and right. The present report (level of evidence, III) provides a method for treating AARF that has similar advantages as dynamic CT but avoids ionizing radiation by replacing CT with interventional MRI. The new method comprised simultaneous axial traction and manual closed reduction, performed under general anesthesia, and the use of interventional MRI to ensure that reduction was achieved and held. The head is turned maximally to the right and left during the manual reduction. A rigid cervical collar was used following reduction. Dynamic CT was not required but prior diagnostic static CT was performed in preparation. No further CT was required. There appears to be no previous studies on interventional MRI in AARF care. Being superior in its diagnostic soft-tissue visualization performance and lacking ionizing radiation, interventional MRI is a potential option for investigating and treating acute AARF in non-syndromic patients with no trauma history.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/etm.2019.7565DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6566071PMC
July 2019

A new breast tomosynthesis imaging method: Continuous Sync-and-Shoot - technical feasibility and initial experience.

Acta Radiol Open 2019 Mar 15;8(3):2058460119836255. Epub 2019 Mar 15.

Turku University Hospital, Turku, Finland.

Background: Digital breast tomosynthesis (DBT) is gaining popularity in breast imaging. There are several different technical approaches for conducting DBT imaging.

Purpose: To determine optimal imaging parameters, test patient friendliness, evaluate the initial diagnostic performance, and describe diagnostic advances possible with the new Continuous Sync-and-Shoot method.

Material And Methods: Thirty-six surgical breast specimens were imaged with digital mammography (DM) and a prototype of a DBT system (Planmed Oy, Helsinki, Finland). We tested the patient friendliness of the sync-and-shoot movement without radiation exposure in eight volunteers. Different imaging parameters were tested with 20 specimens to identify the optimal combination: angular range 30°, 40°, and 60°; pixel binning; Rhodium (Rh) and Silver (Ag) filtrations; and different kV and mAs values. Two breast radiologists evaluated 16 DM and DBT image pairs and rated six different image properties. Imaging modalities were compared with paired t-test.

Results: The Continuous Sync-and-Shoot method produced diagnostically valid images. Five out of eight volunteers felt no/minimal discomfort, three experienced mild discomfort from the tilting movement of the detector, with the motion being barely recognized. The combination of 30°, Ag filtering, and 2 × 2 pixel binning produced the best image quality at an acceptable dose level. DBT was significantly better in all six evaluated properties ( < 0.05). Mean Dose/Dose ratio was 1.22 (SD = 0.42).

Conclusion: The evaluated imaging method is feasible for imaging and analysing surgical breast specimens and DBT is significantly better than DM in image evaluation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/2058460119836255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6421620PMC
March 2019

Wedged gel pad for bowel manipulation during MR-guided high-intensity focused ultrasound therapy to treat uterine fibroids: a case report.

J Ther Ultrasound 2018 28;6:10. Epub 2018 Nov 28.

1Medical Imaging Centre of Southwest Finland, University of Turku and Turku University Hospital, Turku, Finland.

Background: Magnetic resonance guided high-intensity focused ultrasound (MR-HIFU) therapy is not feasible in all patients with uterine fibroids because of limiting anatomical factors such as scar tissue, bowel loops or other obstacles in the sonication path. These may prevent the treatment or limit the treatment window, and therefore, also the volume where HIFU therapy can be delivered. Bowel loops present a particular problem because of bowel gas bubbles and hard particles which may cause reflection or absorption of ultrasound energy, potentially leading to thermal damage and even bowel perforation. Most commonly used techniques for bowel repositioning are bladder and/or rectum filling but these are not always sufficient to reposition the bowel loops. With more efficient bowel repositioning technique, the number of eligible patients for MR-HIFU treatment could be increased, and therapy efficacy be improved in cases where bowel loops limit the treatment window.

Case Presentation: A wedged exterior gel pad was used in two patients presented with in total of four symptomatic fibroids undergoing MR-HIFU treatment when bladder and/or rectum filling was not sufficient to reposition the bowel loops. No severe adverse effects were observed in these cases. The non-perfused volume ratios (NPVs) immediately after treatment were 86% and 39% for the first patient, and 3% for the second patient.

Conclusions: Our preliminary experience suggests that the use of a wedged gel pad during MR-HIFU treatment could be an effective tool to manipulate the bowels in cases where the bladder and/or rectum filling is not sufficient to reposition the bowel loops. A wedged gel pad could also be used in other situations to achieve better treatment coverage to the uterine fibroid.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s40349-018-0116-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6260726PMC
November 2018

Real-time MR-guided brain biopsy using 1.0-T open MRI scanner.

Eur Radiol 2019 Jan 12;29(1):85-92. Epub 2018 Jun 12.

Department of Interventional MRI, Shandong Medical Imaging Research Institute affiliated to Shandong University, Shandong Key Laboratory of Advanced Medical Imaging Technologies and Applications, Jinan, Shandong, People's Republic of China.

Objectives: To evaluate the safety, feasibility and diagnostic performance of real-time MR-guided brain biopsy using a 1.0-T open MRI scanner.

Methods: Medical records of 86 consecutive participants who underwent brain biopsy under the guidance of a 1.0-T open MRI scanner with real-time and MR fluoroscopy techniques were evaluated retrospectively. All procedures were performed under local anaesthesia and intravenous conscious sedation. Diagnostic yield, diagnostic accuracy, complication rate and procedure duration were assessed. The lesions were divided into two groups according to maximum diameters: ≤ 1.5 cm (n = 16) and > 1.5 cm (n = 70). The two groups were compared using Fisher's exact test.

Results: Diagnostic yield and diagnostic accuracy were 95.3% and 94.2%, respectively. The diagnostic yield of lesions ≤ 1.5 cm and > 1.5 cm were 93.8% and 95.7%, respectively. There was no significant difference in diagnostic yield between the two groups (p > 0.05). Mean procedure duration was 41 ± 5 min (range 33-49 min). All biopsy needles were placed with one pass. Complication rate was 3.5% (3/86). Minor complications included three cases of a small amount of haemorrhage. No serious complications were observed.

Conclusions: Real-time MR-guided brain biopsy using a 1.0-T open MRI scanner is a safe, feasible and accurate diagnostic technique for pathological diagnosis of brain lesions. The procedure duration is shortened and biopsy work flow is simplified. It could be considered as an alternative for brain biopsy.

Key Points: • Real-time MRI-guided brain biopsy using a 1.0-T open MRI scanner is safe, feasible and accurate. • No serious complications occurred in real-time MRI-guided brain biopsy. • Procedure duration is shortened and biopsy work flow is simplified.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00330-018-5531-yDOI Listing
January 2019

A prospective development study of software-guided radio-frequency ablation of primary and secondary liver tumors: Clinical intervention modelling, planning and proof for ablation cancer treatment (ClinicIMPPACT).

Contemp Clin Trials Commun 2017 Dec 18;8:25-32. Epub 2017 Aug 18.

Department of Diagnostic and Interventional Radiology, University Hospital Leipzig, Germany.

Introduction: Radio-frequency ablation (RFA) is a promising minimal-invasive treatment option for early liver cancer, however monitoring or predicting the size of the resulting tissue necrosis during the RFA-procedure is a challenging task, potentially resulting in a significant rate of under- or over treatments. Currently there is no reliable lesion size prediction method commercially available.

Objectives: ClinicIMPPACT is designed as multicenter-, prospective-, non-randomized clinical trial to evaluate the accuracy and efficiency of innovative planning and simulation software. 60 patients with early liver cancer will be included at four European clinical institutions and treated with the same RFA system. The preinterventional imaging datasets will be used for computational planning of the RFA treatment. All ablations will be simulated simultaneously to the actual RFA procedure, using the software environment developed in this project. The primary outcome measure is the comparison of the simulated ablation zones with the true lesions shown in follow-up imaging after one month, to assess accuracy of the lesion prediction.

Discussion: This unique multicenter clinical trial aims at the clinical integration of a dedicated software solution to accurately predict lesion size and shape after radiofrequency ablation of liver tumors. Accelerated and optimized workflow integration, and real-time intraoperative image processing, as well as inclusion of patient specific information, e.g. organ perfusion and registration of the real RFA needle position might make the introduced software a powerful tool for interventional radiologists to optimize patient outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.conctc.2017.08.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5898513PMC
December 2017

Pediatric Musculoskeletal Interventional MRI.

Top Magn Reson Imaging 2018 Feb;27(1):39-44

Russell H. Morgan Department of Radiology and Radiological Science, Musculoskeletal Radiology, Johns Hopkins University School of Medicine, Baltimore, MD.

Minimally invasive procedures play a crucial role in the diagnosis and treatment of many pediatric musculoskeletal conditions. Although computed tomography and fluoroscopy are commonly used for image guidance, the associated exposure to ionizing radiation is especially concerning in pediatric patients. Ultrasonography may be used successfully in a subset of interventions, but it is often not useful for complex, deep, and osseous targets. Interventional magnetic resonance imaging (iMRI) facilitates targeting and treatment of musculoskeletal lesions at many locations with high accuracy due to its excellent tissue contrast. Furthermore, MRI provides imaging guidance without the use of ionizing radiation and as such complies with the ALARA practice mandate in a formidable fashion. MRI guidance is our method of choice for lesion that are not visible by other modalities or when other techniques and modalities failed. MRI guidance is especially useful for selective targeting of complex lesions, intra-articular lesions, cyst aspirations in difficult locations of the body, and lesions that are located adjacent to surgical hardware. Tumor-related diagnostic sampling is more frequently performed under MRI; however, MRI guidance is also exquisitely well suited for a variety of therapeutic percutaneous osseous or articular conditions, such as osteoid osteoma, epiphyseal bone bridging, osteochondritis dissecans lesions, and aneurysmal bone cysts. In this article, we will describe the technical aspects and clinical indications of a variety of MRI-guided pediatric procedures in the musculoskeletal system.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/RMR.0000000000000143DOI Listing
February 2018

RFA Guardian: Comprehensive Simulation of Radiofrequency Ablation Treatment of Liver Tumors.

Sci Rep 2018 01 15;8(1):787. Epub 2018 Jan 15.

University Hospital Leipzig, Clinic for Diagnostic and Interventional Radiology, Leipzig, 04109, Germany.

The RFA Guardian is a comprehensive application for high-performance patient-specific simulation of radiofrequency ablation of liver tumors. We address a wide range of usage scenarios. These include pre-interventional planning, sampling of the parameter space for uncertainty estimation, treatment evaluation and, in the worst case, failure analysis. The RFA Guardian is the first of its kind that exhibits sufficient performance for simulating treatment outcomes during the intervention. We achieve this by combining a large number of high-performance image processing, biomechanical simulation and visualization techniques into a generalized technical workflow. Further, we wrap the feature set into a single, integrated application, which exploits all available resources of standard consumer hardware, including massively parallel computing on graphics processing units. This allows us to predict or reproduce treatment outcomes on a single personal computer with high computational performance and high accuracy. The resulting low demand for infrastructure enables easy and cost-efficient integration into the clinical routine. We present a number of evaluation cases from the clinical practice where users performed the whole technical workflow from patient-specific modeling to final validation and highlight the opportunities arising from our fast, accurate prediction techniques.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-017-18899-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5768804PMC
January 2018

High intensity focused ultrasound (HIFU) in tumor therapy.

Duodecim 2017;133(2):143-9

HIFU (high intensity focused ultrasound) is a method in which high-frequency ultrasound is focused on a tissue in order to achieve a thermal effect and the subsequent percutaneously ablation, or tissue modulation. HIFU is non-invasive and results in an immediate tissue destruction effect corresponding to surgery, either percutaneously or through body cavities. HIFU can be utilized in the treatment of both benign and malignant tumors. In neurological diseases, focused HIFU can be used in the treatment of disorders of the basal ganglia.
View Article and Find Full Text PDF

Download full-text PDF

Source
January 2018

GPU-based RFA simulation for minimally invasive cancer treatment of liver tumours.

Int J Comput Assist Radiol Surg 2017 Jan 18;12(1):59-68. Epub 2016 Aug 18.

Fraunhofer Institute for Applied Information Technology, Sankt Augustin, Germany.

Purpose: Radiofrequency ablation (RFA) is one of the most popular and well-standardized minimally invasive cancer treatments (MICT) for liver tumours, employed where surgical resection has been contraindicated. Less-experienced interventional radiologists (IRs) require an appropriate planning tool for the treatment to help avoid incomplete treatment and so reduce the tumour recurrence risk. Although a few tools are available to predict the ablation lesion geometry, the process is computationally expensive. Also, in our implementation, a few patient-specific parameters are used to improve the accuracy of the lesion prediction.

Methods: Advanced heterogeneous computing using personal computers, incorporating the graphics processing unit (GPU) and the central processing unit (CPU), is proposed to predict the ablation lesion geometry. The most recent GPU technology is used to accelerate the finite element approximation of Penne's bioheat equation and a three state cell model. Patient-specific input parameters are used in the bioheat model to improve accuracy of the predicted lesion.

Results: A fast GPU-based RFA solver is developed to predict the lesion by doing most of the computational tasks in the GPU, while reserving the CPU for concurrent tasks such as lesion extraction based on the heat deposition at each finite element node. The solver takes less than 3 min for a treatment duration of 26 min. When the model receives patient-specific input parameters, the deviation between real and predicted lesion is below 3 mm.

Conclusion: A multi-centre retrospective study indicates that the fast RFA solver is capable of providing the IR with the predicted lesion in the short time period before the intervention begins when the patient has been clinically prepared for the treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11548-016-1469-1DOI Listing
January 2017

MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open high-field MRI scanner with respiratory gating.

Eur Radiol 2017 Apr 11;27(4):1459-1466. Epub 2016 Aug 11.

Department of Interventional MRI, Shandong Medical Imaging Research Institute affiliated to Shandong University, Shandong Key Laboratory of Advanced Medical Imaging Technologies and Applications, Jinan, Shandong, People's Republic of China.

Objectives: To prospectively evaluate the feasibility, safety and accuracy of MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open MR scanner with respiratory gating.

Methods: Sixty-five patients with 65 solitary pulmonary lesions underwent MR-guided percutaneous coaxial cutting needle biopsy using a 1.0-T open MR scanner with respiratory gating. Lesions were divided into two groups according to maximum lesion diameters: ≤2.0 cm (n = 31) and >2.0 cm (n = 34). The final diagnosis was established in surgery and subsequent histology. Diagnostic accuracy, sensitivity and specificity were compared between the groups using Fisher's exact test.

Results: Accuracy, sensitivity and specificity of MRI-guided percutaneous pulmonary biopsy in diagnosing malignancy were 96.9 %, 96.4 % and 100 %, respectively. Accuracy, sensitivity and specificity were 96.8 %, 96.3 % and 100 % for lesions 2.0 cm or smaller and 97.1 %, 96.4 % and 100 %, respectively, for lesions larger than 2.0 cm. There was no significant difference between the two groups (P > 0.05). Biopsy-induced complications encountered were pneumothorax in 12.3 % (8/65) and haemoptysis in 4.6 % (3/65). There were no serious complications.

Conclusions: MRI-guided percutaneous biopsy using a 1.0-T open MR scanner with respiratory gating is an accurate and safe diagnostic technique in evaluation of pulmonary lesions.

Key Points: • MRI-guided percutaneous lung biopsy using a 1.0-T open MR scanner is feasibility. • 96.9 % differentiation accuracy of malignant and benign lung lesions is possible. • No serious complications occurred in MRI-guided lung biopsy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00330-016-4518-9DOI Listing
April 2017

MRI-guidance in percutaneous core decompression of osteonecrosis of the femoral head.

Eur Radiol 2016 Apr 1;26(4):1180-5. Epub 2015 Aug 1.

Department of Radiology, Oulu University Hospital, P.O. Box 50, 90029, Oulu, OYS, Finland.

Objectives: The purpose of this study was to evaluate the usefulness of MRI-guidance for core decompression of avascular necrosis of the femoral head.

Materials And Methods: Twelve MRI-guided core decompressions were performed on patients with different stages of avascular necrosis of the femoral head. The patients were asked to evaluate their pain and their ability to function before and after the procedure and imaging findings were reviewed respectively.

Results: Technical success in reaching the target was 100 % without complications. Mean duration of the procedure itself was 54 min. All patients with ARCO stage 1 osteonecrosis experienced clinical benefit and pathological MRI findings were seen to diminish. Patients with more advanced disease gained less, if any, benefit and total hip arthroplasty was eventually performed on four patients.

Conclusions: MRI-guidance seems technically feasible, accurate and safe for core decompression of avascular necrosis of the femoral head. Patients with early stage osteonecrosis may benefit from the procedure.

Key Points: • MRI is a useful guidance method for minimally invasive musculoskeletal interventions. • Bone drilling seems beneficial at early stages of avascular necrosis. • MRI-guidance is safe and accurate for bone drilling.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00330-015-3905-yDOI Listing
April 2016

MRI-guided percutaneous transpedicular biopsy of thoracic and lumbar spine using a 0.23t scanner with optical instrument tracking.

J Magn Reson Imaging 2015 Dec 6;42(6):1740-6. Epub 2015 May 6.

Department of Interventional MRI, Shandong Medical Imaging Research Institute, Shandong University, Jinan, Shandong, P.R. China.

Purpose: To prospectively evaluate the safety and accuracy of magnetic resonance imaging (MRI)-guided percutaneous transpedicular biopsy of thoracic and lumbar spine using 0.23T magnetic resonance imaging with optical tracking.

Materials And Methods: Sixty-seven thoracic and lumbar spine lesions in 67 patients underwent MRI-guided percutaneous transpedicular biopsy using 0.23T MRI with optical tracking. These lesions were divided into two groups according to the location: 16 lesions in the thoracic spine and 51 lesions in the lumbar spine. The diagnostic accuracy, sensitivity, and specificity were calculated, and comparison of the two groups was performed using Fisher's exact test. Each patient was monitored for complications.

Results: All specimens obtained were sufficient for diagnosis. Histological examination of MRI-guided percutaneous biopsy revealed 38 malignant and 29 benign lesions. The final diagnoses from surgery or clinical follow-up were 42 malignant lesions and 25 benign lesions. The combined diagnostic performance of MRI-guided percutaneous transpedicular thoracic and lumbar biopsy in diagnosing malignant tumors was as follows: accuracy, 94%; sensitivity, 89%; and specificity, 100%. There was no significant difference between the two groups (P = 1, Fisher's exact test). No serious complications occurred.

Conclusion: MRI-guided percutaneous transpedicular biopsy is a safe and accurate diagnostic technique to evaluate thoracic and lumbar spine lesions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jmri.24924DOI Listing
December 2015

High number of transplanted stem cells improves myocardial recovery after AMI in a porcine model.

Scand Cardiovasc J 2015 Apr 18;49(2):82-94. Epub 2015 Mar 18.

Department of Surgery, Clinical Research Center, Oulu University Hospital, Oulu, Finland and Department of Surgery, Institute of Clinical Medicine, University of Oulu , Oulu , Finland.

Objective: The clinical data considering the bone marrow mononuclear cell (BMMNC) therapy in treatment for acute myocardial infarction (AMI) are controversial and the mechanisms remain unknown. Our objective was to study the cardiac function and changes in cytokine levels after administration of BMMNC in experimental AMI model.

Design: Unlabeled or Super-Paramagnetic-Iron-Oxide-labeled BMMNCs or saline was injected into myocardium of 31 pigs after circumflex artery occlusion. Ejection fraction (EF) was measured preoperatively, postoperatively and at 21 days by echocardiography. Cardiac MRI was performed postoperatively and after 21 days in 7 BMMNC animals. Serum cytokine levels were measured at baseline, 24 h and 21 days. Cellular homing was evaluated comparing MRI and histology.

Results: From baseline to 21 days EF decreased less in BMMNC group (EF mean control -19 SD 12 vs. BMMNC -4 SD 15 percentage points p = 0.02). Cytokine concentrations showed high variability between the animals. MRI correlated with histology in cell detection and revealed BMMNCs in the infarction area. By MRI, EF improved 11 percentage points. The improvement in EF was associated with the number of transplanted BMMNCs detected in the myocardium.

Conclusion: BMMNC injection after AMI improved cardiac function. Quantity of transplanted BMMNCs correlated with the improvement in cardiac function after AMI.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3109/14017431.2015.1018311DOI Listing
April 2015

Mesenchymal stromal cells from female donors enhance breast cancer cell proliferation in vitro.

Oncology 2015 11;88(4):214-25. Epub 2014 Dec 11.

Department of Anatomy and Cell Biology, Institute of Biomedicine, University of Oulu, Oulu, Finland.

The interplay between tumor stroma and breast cancer cells (BCCs) is thought to play a significant role in breast cancer. The current knowledge of human mesenchymal stromal cell (MSC) and BCC interaction is contradictory, and the donor sex issue is not addressed at all. We hypothesized that donor sex could have an effect on proliferation of MSCs or BCCs in co-culture in vitro. Three estrogen receptor-negative BCC lines, 19 primary human MSCs and breast tissue-derived fibroblasts from 4 donors were used. MSCs from female donors enhanced BCC proliferation (p = 0.005). The change in BCC proliferation was only partly due to soluble factors excreted by MSCs. The highly aggressive BCC line MDA-MB- 231 induced the proliferation of MSCs (p < 0.001) and fibroblasts (p = 0.037) in co-culture experiments. The magnitude in proliferation change was cell line dependent and partly sex dependent.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000368556DOI Listing
June 2015

Automatic segmentation for detecting uterine fibroid regions treated with MR-guided high intensity focused ultrasound (MR-HIFU).

Med Phys 2014 Jul;41(7):073502

MR-Therapy, Philips Healthcare, FI-01511 Vantaa, Finland.

Purpose: Up to 25% of women suffer from uterine fibroids (UF) that cause infertility, pain, and discomfort. MR-guided high intensity focused ultrasound (MR-HIFU) is an emerging technique for noninvasive, computer-guided thermal ablation of UFs. The volume of induced necrosis is a predictor of the success of the treatment. However, accurate volume assessment by hand can be time consuming, and quick tools produce biased results. Therefore, fast and reliable tools are required in order to estimate the technical treatment outcome during the therapy event so as to predict symptom relief.

Methods: A novel technique has been developed for the segmentation and volume assessment of the treated region. Conventional algorithms typically require user interaction ora priori knowledge of the target. The developed algorithm exploits the treatment plan, the coordinates of the intended ablation, for fully automatic segmentation with no user input.

Results: A good similarity to an expert-segmented manual reference was achieved (Dice similarity coefficient = 0.880 ± 0.074). The average automatic segmentation time was 1.6 ± 0.7 min per patient against an order of tens of minutes when done manually.

Conclusions: The results suggest that the segmentation algorithm developed, requiring no user-input, provides a feasible and practical approach for the automatic evaluation of the boundary and volume of the HIFU-treated region.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1118/1.4881319DOI Listing
July 2014

HIF prolyl 4-hydroxylase-2 inhibition improves glucose and lipid metabolism and protects against obesity and metabolic dysfunction.

Diabetes 2014 Oct 1;63(10):3324-33. Epub 2014 May 1.

Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, Oulu Center for Cell-Matrix Research, University of Oulu, FIN-90014 Oulu, Finland

Obesity is a major public health problem, predisposing subjects to metabolic syndrome, type 2 diabetes, and cardiovascular diseases. Specific prolyl 4-hydroxylases (P4Hs) regulate the stability of the hypoxia-inducible factor (HIF), a potent governor of metabolism, with isoenzyme 2 being the main regulator. We investigated whether HIF-P4H-2 inhibition could be used to treat obesity and its consequences. Hif-p4h-2-deficient mice, whether fed normal chow or a high-fat diet, had less adipose tissue, smaller adipocytes, and less adipose tissue inflammation than their littermates. They also had improved glucose tolerance and insulin sensitivity. Furthermore, the mRNA levels of the HIF-1 targets glucose transporters, glycolytic enzymes, and pyruvate dehydrogenase kinase-1 were increased in their tissues, whereas acetyl-CoA concentration was decreased. The hepatic mRNA level of the HIF-2 target insulin receptor substrate-2 was higher, whereas that of two key enzymes of fatty acid synthesis was lower. Serum cholesterol levels and de novo lipid synthesis were decreased, and the mice were protected against hepatic steatosis. Oral administration of an HIF-P4H inhibitor, FG-4497, to wild-type mice with metabolic dysfunction phenocopied these beneficial effects. HIF-P4H-2 inhibition may be a novel therapy that not only protects against the development of obesity and its consequences but also reverses these conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2337/db14-0472DOI Listing
October 2014

MRI-guided laser ablation of neuroendocrine tumor hepatic metastases.

Acta Radiol Short Rep 2014 Jan 23;3(1):2047981613499753. Epub 2014 Jan 23.

Department of Radiology, Oulu University Hospital, Oulu, Finland.

Background: Neuroendocrine tumors (NET) represent a therapeutically challenging and heterogeneous group of malignancies occurring throughout the body, but mainly in the gastrointestinal system.

Purpose: To describe magnetic resonance imaging (MRI)-guided laser ablation of NET liver metastases and assess its role within the current treatment options and methods.

Material And Methods: Two patients with NET tumor hepatic metastases were treated with MRI-guided interstitial laser ablation (LITT). Three tumors were treated. Clinical follow-up time was 10 years.

Results: Both patients were successfully treated. There were no local recurrences at the ablation site during the follow-up. Both patients had survived at 10-year follow-up. One patient is disease-free.

Conclusion: MRI-guided laser ablation can be used to treat NET tumor liver metastases but combination therapy and a rigorous follow-up schedule are recommended.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/2047981613499753DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4001425PMC
January 2014