Magnetic Resonance Imaging Fusion Research Articles

Early soft and flexible fusion of electroencephalography and functional magnetic resonance imaging via double coupled matrix tensor factorization for multisubject group analysis.

Data fusion refers to the joint analysis of multiple datasets that provide different (e.g., complementary) views of the same task. In general, it can extract more information than separate analyses can. Jointly analyzing electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) measurements has been proved to be highly beneficial to the study of the brain function, mainly because these neuroimaging modalities have complementary spatiotemporal resolution: EEG offers good temporal resolution while fMRI is better in its spatial resolution. The EEG–fMRI fusion methods that have been reported so far ignore the underlying multiway nature of the data in at least one of the modalities and/or rely on very strong assumptions concerning the relation of the respective datasets. For example, in multisubject analysis, it is commonly assumed that the hemodynamic response function is a priori known for all subjects and/or the coupling across corresponding modes is assumed to be exact (hard). In this article, these two limitations are overcome by adopting tensor models for both modalities and by following soft and flexible coupling approaches to implement the multimodal fusion. The obtained results are compared against those of parallel independent component analysis and hard coupling alternatives, with both synthetic and real data (epilepsy and visual oddball paradigm). Our results demonstrate the clear advantage of using soft and flexible coupled tensor decompositions in scenarios that do not conform with the hard coupling assumption.

The Fusion of MRI and CT Medical Images Using Variational Mode Decomposition

In medical image processing, magnetic resonance imaging (MRI) and computed tomography (CT) modalities are widely used to extract soft and hard tissue information, respectively. However, with the help of a single modality, it is very challenging to extract the required pathological features to identify suspicious tissue details. Several medical image fusion methods have attempted to combine complementary information from MRI and CT to address the issue mentioned earlier over the past few decades. However, existing methods have their advantages and drawbacks. In this work, we propose a new multimodal medical image fusion approach based on variational mode decomposition (VMD) and local energy maxima (LEM). With the help of VMD, we decompose source images into several intrinsic mode functions (IMFs) to effectively extract edge details by avoiding boundary distortions. LEM is employed to carefully combine the IMFs based on the local information, which plays a crucial role in the fused image quality by preserving the appropriate spatial information. The proposed method’s performance is evaluated using various subjective and objective measures. The experimental analysis shows that the proposed method gives promising results compared to other existing and well-received fusion methods.

High-Dose Rate Interstitial Spine Brachytherapy Using an Intraoperative Mobile Computed Tomography-Guided Surgical Navigation System.

Up to 15% of previously irradiated metastatic spine tumors will progress. Re-irradiation of these tumors poses a significant risk of exceeding the radiation tolerance to the spinal cord. High-dose rate (HDR) brachytherapy is a treatment alternative. To develop a novel HDR spine brachytherapy technique using an intraoperative computed tomography-guided navigation (iCT navigation). Patients with progressive metastatic spine tumors were included in the study. HDR brachytherapy catheters were placed under iCT navigation. CT-based planning with magnetic resonance imaging fusion was performed to ensure conformal dose delivery to the target while sparing normal tissue, including the spinal cord. Patients received single fraction radiation treatment. Five patients with thoracolumbar tumors were treated with HDR brachytherapy. Four patients previously received radiotherapy to the same spinal level. Preimplant plans demonstrated median clinical target volume (CTV) D90 of 116.5% (110.8%-147.7%), V100 of 95.7% (95.5%-99.6%), and Dmax of 8.08 Gy (7.65-9.8 Gy) to the spinal cord/cauda equina. Postimplant plans provided median CTV D90 of 113.8% (93.6%-120.1%), V100 of 95.9% (87%-99%), and Dmax of 9.48 Gy (6.5-10.3 Gy) to cord/cauda equina. Patients who presented with back pain (n=3) noted symptomatic improvement at a median follow-up of 22 d after treatment. Four patients demonstrated local tumor control of spinal metastatic tumor at a median follow-up of 92 d after treatment. One patient demonstrated radiographic evidence of local tumor progression 2.7 mo after treatment. HDR spine brachytherapy with iCT navigation is a promising treatment alternative to induce local tumor control and reduce pain symptoms associated with metastatic spine disease.

The value of magnetic resonance imaging and ultrasonography (MRI/US)-fusion biopsy in clinically significant prostate cancer detection in patients with biopsy-naïve men according to PSA levels: Apropensity score matching analysis.

ObjectivesTo evaluate the detection rate of clinically significant prostate cancer (csPCa) in Magnetic resonance imaging and ultrasonography (MRI/US) fusion biopsy in patients with biopsy-naïve men for varying prostate-specific antigen (PSA) levels. Since MRI can efficiently detect csPCa compared to standard transrectal ultrasound (TRUS) guided biopsy; however, the optimal PSA threshold for its use is unclear.Materials and methodsWe retrospectively reviewed those who underwent MRI/US-fusion and standard biopsy from January 2016 to June 2018. Patients were divided into three groups: PSA <4, 4–10, >10 ng/mL. Propensity scoring was performed to balance the characteristics of the different biopsy groups, and the detection rate of csPCa was compared.ResultsData from a total of 670 males were included in the analysis (standard TRUS, n = 333; MRI/US fusion, n = 337). Prior to matching, patients who received MRI/US-fusion biopsy had lower prostate volume. Propensity score matching balanced this characteristic and generated a cohort comprising 195 patients from each group. In the matched cohort, patients with PSA 4–10 ng/mL had a significantly increased risk of csPCa by MRI/US-fusion vs. standard biopsy (35.0% vs. 26.6%, P = 0.033). However, patients with PSA <4 ng/mL had csPCa found by MRI/US-fusion versus standard biopsy (12.0% vs. 16.0%, P = 0.342), whereas, patients with PSA >10 ng/mL had csPCa found by MRI/US-fusion versus standard biopsy (78.0% vs. 80.0%, P = 0.596). In multivariate logistic analysis among patients with PSA 4-10 ng/mL, MRI/US-fusion biopsy (odds ratio: 2.46, 95% confidence interval = 1.31–4.60, P = 0.005) were significantly associated with a detection of csPCa.ConclusionsDetection of csPCa by MRI/US-fusion biopsy is more efficient in patients with biopsy-naïve men with PSA 4–10 ng/mL. However, standard TRUS biopsy may identify csPCa in patients with PSA <4 ng/mL and ≥10 ng/mL, emphasizing the importance of performing a standard biopsy in conjunction with MRI/US-fusion biopsy in such populations.

Cerebral Arteriovenous Malformations Treated With Linear Accelerator Stereotactic Radiosurgery Guided by Magnetic Resonance Imaging and Panangiography: A Latin American Experience

Cerebral arteriovenous malformations (AVM) are vascular lesions that include aberrant communication between arterial and venous systems. Treatment for AVM is still under debate. Surgery, embolization, observation, and radiosurgery are options for patients. Most data for radiosurgery came from the Gammaknife series. However, low middle-income countries have financial constraints to establish dedicated intracranial neurosurgery machines. We aimed to determine AVM obliteration rate in patients treated with linear accelerator stereotactic radiosurgery (SRS) guided by magnetic resonance imaging and panangiography fusion with computed tomography simulation at a quaternary care institution in Latin America.We conducted an observational study with patients treated with SRS at our institution during 2011 and 2017. Exclusion criteria were age younger than 14 and a history of brain cancer. After IRB approval, data were collected retrospectively by reviewing medical records. Patients without available follow-up were contacted to gather missing information. Primary outcome was obliteration rate at 3 years, confirmed by diagnostic imaging (MRI or cerebral panangiography). Secondary outcomes were intracranial bleeding, headaches, epilepsy, and neurological deficits at clinical presentation and after SRS. Analysis included sociodemographic data, AVM characteristics (location and Spetzler-Martin grading), and treatment features. We used descriptive statistics, measures of central tendency and dispersion, and proportions.We included 85 patients. The mean age at treatment was 40.8 (14-73), 49.4% of patients were male, and 50.6% female. The most common location was the frontal lobe in 25.9% (n = 22) and the parietal lobe in 24.7% (n = 21). At diagnosis, 44% of patients had a history of intracranial hemorrhage. 49 patients had received previous embolization. The mean dose of radiosurgery was 19.3 Gy (14-25). The mean isodose was 95.25 (80-98). 35.3% of the patients had an AVM Spetzler-Martin grade 2, 40% grade 3, and 12.9% grade 4. We obtained long-term follow-up data for 42 patients, with a median follow-up of 1366 days. The overall obliteration rate was 60%, based primarily on panangiography (59.1%). Symptoms after SRS included headaches (n = 30) and seizures (n = 10). 2 patients presented intracranial bleeding. We contacted all missing patients, but no follow-up data was available for analysis. Most missing patients lived outside the city.Tri-modality image fusion SRS with linear accelerators for AVM could be a safe and accessible option in low-middle income countries. Health administrator issues, travel distances to access linear accelerators and multidisciplinary teams hinder timely follow-up and surveillance imaging. More prospective data are needed to define the role of SRS for AVMs.V. Rangel: None. J. Cure: None. M. Caicedo-Martinez: None. G. Borda: None. C. Lindado: None. E. Castro-Lombana: None. J. Puentes: None. O. Zorro: None. A. González-Motta: None.

MP05-04 CLINICALLY SIGNIFICANT PROSTATE CANCER DETECTION RATES ON MRI GUIDED FUSION NEEDLE BIOPSY - EXPERIENCE FROM THE PENNSYLVANIA UROLOGIC REGIONAL COLLABORATIVE

You have accessJournal of UrologyProstate Cancer: Detection & Screening I (MP05)1 Sep 2021MP05-04 CLINICALLY SIGNIFICANT PROSTATE CANCER DETECTION RATES ON MRI GUIDED FUSION NEEDLE BIOPSY - EXPERIENCE FROM THE PENNSYLVANIA UROLOGIC REGIONAL COLLABORATIVE Ako Adams Ako, Serge Ginzburg, Eric Singer, Bruce Jacobs, Claudette Fonshell, Adam Reese, Edouard Trabulsi, Jeffery Tomaszewski, John Danella, Laurence Belkoff, Thomas Guzzo, Robert Uzzo, and Jay Raman Ako Adams AkoAko Adams Ako More articles by this author , Serge GinzburgSerge Ginzburg More articles by this author , Eric SingerEric Singer More articles by this author , Bruce JacobsBruce Jacobs More articles by this author , Claudette FonshellClaudette Fonshell More articles by this author , Adam ReeseAdam Reese More articles by this author , Edouard TrabulsiEdouard Trabulsi More articles by this author , Jeffery TomaszewskiJeffery Tomaszewski More articles by this author , John DanellaJohn Danella More articles by this author , Laurence BelkoffLaurence Belkoff More articles by this author , Thomas GuzzoThomas Guzzo More articles by this author , Robert UzzoRobert Uzzo More articles by this author , and Jay RamanJay Raman More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001972.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Magnetic resonance imaging (MRI) fusion needle biopsy has been shown to outperform systematic biopsy in detecting clinically significant prostate cancer. This study sought to: 1) Examine the variability of clinically significant prostate cancer detection rates in a large, regional quality improvement collaborative. 2) Examine the association between patient characteristics and clinically significant prostate cancer detection. METHODS: The Pennsylvania Urologic Regional Collaborative (PURC) is a physician-led data-sharing and quality improvement collaborative comprised of urology practices across Pennsylvania and New Jersey. We analyzed 857 first-time MRI fusion biopsy procedures performed at 5 PURC practices with a minimum of 30 procedures between January 2015 and June 2019. Chi-square tests and hierarchical logistic regression analyzed the variability in cancer detection rates by practice and the association between patient characteristics and Gleason ≥4+3 tumor detection. RESULTS: Median prostate specific antigen (PSA) was 6.8 ng/ml, 14.4% of men were ≤59 years old. Detection rates for Gleason ≥4+3 tumors by practice ranged from 14.3% to 28.3% (p=0.02). Age, digital rectal examination, PSA, gland volume and Prostate Imaging-Reporting and Data System version2 (PI-RADSv2) score were significantly associated with Gleason ≥4+3 tumors. Adjusting for patient characteristics demonstrated that there was no significant variation in Gleason ≥4+3 tumor detection by practice (Intercept variance = 0.04; p=0.26). PIRADSv2 ≥4 was associated with increased likelihood of detecting a Gleason ≥4+3 tumor (OR 2.67; 95% CI 1.76–4.07; p<0.0001). CONCLUSIONS: Variability in clinically significant prostate cancer detection between individual practice sites was predominantly due to variability in patient characteristics. Results highlight the importance of pre-biopsy MRI in the diagnosis of clinically significant prostate cancer. Source of Funding: None © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e77-e78 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ako Adams Ako More articles by this author Serge Ginzburg More articles by this author Eric Singer More articles by this author Bruce Jacobs More articles by this author Claudette Fonshell More articles by this author Adam Reese More articles by this author Edouard Trabulsi More articles by this author Jeffery Tomaszewski More articles by this author John Danella More articles by this author Laurence Belkoff More articles by this author Thomas Guzzo More articles by this author Robert Uzzo More articles by this author Jay Raman More articles by this author Expand All Advertisement Loading ...

Brain multimodal co-alterations related to delay discounting: a multimodal MRI fusion analysis in persons with and without cocaine use disorder

BackgroundDelay discounting has been proposed as a behavioral marker of substance use disorders. Innovative analytic approaches that integrate information from multiple neuroimaging modalities can provide new insights into the complex effects of drug use on the brain. This study implemented a supervised multimodal fusion approach to reveal neural networks associated with delay discounting that distinguish persons with and without cocaine use disorder (CUD).MethodsAdults with (n = 35) and without (n = 37) CUD completed a magnetic resonance imaging (MRI) scan to acquire high-resolution anatomical, resting-state functional, and diffusion-weighted images. Pre-computed features from each data modality included whole-brain voxel-wise maps for gray matter volume, fractional anisotropy, and regional homogeneity, respectively. With delay discounting as the reference, multimodal canonical component analysis plus joint independent component analysis was used to identify co-alterations in brain structure and function.ResultsThe sample was 58% male and 78% African–American. As expected, participants with CUD had higher delay discounting compared to those without CUD. One joint component was identified that correlated with delay discounting across all modalities, involving regions in the thalamus, dorsal striatum, frontopolar cortex, occipital lobe, and corpus callosum. The components were negatively correlated with delay discounting, such that weaker loadings were associated with higher discounting. The component loadings were lower in persons with CUD, meaning the component was expressed less strongly.ConclusionsOur findings reveal structural and functional co-alterations linked to delay discounting, particularly in brain regions involved in reward salience, executive control, and visual attention and connecting white matter tracts. Importantly, these multimodal networks were weaker in persons with CUD, indicating less cognitive control that may contribute to impulsive behaviors.

Expedited Workflow for “One-Stop” Magnetic Resonance Imaging and Image Fusion Prostate Biopsy: Implementation and Lessons Learned

Abstract While the standard two-day workflow for magnetic resonance imaging guided ultrasound biopsy of the prostate grants flexibility to health care providers, a one-stop diagnostic pathway may benefit patients. A working relationship between radiology and urology is essential in implementing a streamlined workflow and built-in feedback loops to identify/prevent pitfalls as they arise. Another consideration is the overlap in patient populations at risk for prostate cancer and for poor outcomes from COVID19. Same day MRI and prostate biopsy protocols can reduce hospital/clinic visits and has the potential to optimize patient safety by minimizing the risk of COVID-19 exposure to high risk populations.

Morphological analysis of Kambin's triangle using 3D CT/MRI fusion imaging of lumbar nerve root created automatically with artificial intelligence.

We developed a software program that automatically extracts a three-dimensional (3D) lumbar nerve root image from magnetic resonance imaging (MRI) lumbar nerve volume data using artificial intelligence. The aim of this study is to evaluate the morphology of Kambin's triangle in three dimensions based on an actual endoscopic transforaminal surgical approach using three-dimensional (3D) computed tomography (CT)/ magnetic resonance imaging (MRI) fusion images of the lumbar spine and nerve tissue. Three-dimensional lumbar spine/nerve images of 100 patients (31 males and 69 females; mean age, 66.8years) were used to evaluate the relationship between the superior articular process (SAP), exiting nerve root (ENR), and dural canal at the L2/3, L3/4, and L4/5 levels at 45° and 60° approach angles. The SAP-ENR distance at 60° was the greatest at L4/5 and was significantly greater at L2/3 and L4/5 than at L3/4 (P < 0.01, P < 0.01, respectively). The SAP-ENR distance at 45° was the greatest at L2/3, and it was larger in L2/3 and L4/5 than in L3/4 (P < 0.01, P < 0.01, respectively). The SAP-ENR distances at L4/5 were significantly greater at 60° than at 45° (P < 0.01). The dural canal was located within Kambin's triangle on the plane of the upper endplate of the lower vertebra at L2/3 in 41.5% of the cases and at L3/4 in 14% of the cases at 60° but not at L4/5. The 3D lumbar spine/nerve image enabled a combined assessment of the positional relationship between the SAP, ENR, and dural canal to quantify the safety zone of practical endoscopic spinal surgery using a transforaminal approach. Three-dimensional lumbar spine/nerve images could be useful for examining parameters, including bones and nerves, to ensure the safety of surgery.

Multi-Parameter Magnetic Resonance Imaging Fusion Technology Assists in Bone Diagnosis and Rehabilitation of Prostate Cancer

Multi-parameter magnetic resonance imaging has been widely used in the diagnosis and evaluation of prostate cancer, and has important guiding significance for clinical diagnosis of prostate cancer and their treatment. This article studies the value of transrectal multiparametric ultrasound (mpUSS) in the diagnosis of clinically meaningful prostate cancer. 102 patients with high risk factors for prostate cancer were examined by mpUSS and mpMRI. The transrectal biopsy (SB) results of the prostate system were regarded as the excellent standard, and the diagnostic value of mpUSS, mpMRl and mpUSS combined with mpMRl examination for clinically meaningful prostate cancer was analyzed. The results showed that 58 of the 102 patients with SB were diagnosed with prostate cancer. Among them, 43 cases were detected by mpUSS, 50 cases were detected by mpMRl, 42 cases were detected by mpUSS combined with mpMRI (series), and 56 cases were detected by mpUSS combined with mpMRl (parallel). Grouped by Gleason score, the detection rate of mpUSS for clinically significant prostate cancer was 83.74%, and the detection rate of mpMRl was 93.5%. The comparison between the two was not statistically significant (P &gt; 0.05), but when the two inspection methods were combined. The detection rate was 97.8%, which was significantly higher than the two inspection methods alone. Therefore, we conclude that mpUSS can be used as an imaging test for the diagnosis of prostate cancer. In addition, mpUSS has a high application value in the diagnosis of prostate cancer. The detection rate of mpUSS combined with mpMRl examination for clinically meaningful prostate cancer is significantly higher than that of mpMRl examination alone, which can be used as a diagnostic technique for early diagnosis of meaningful prostate cancer and can be used as a guide clinicians’ early diagnosis and treatment of meaningful prostate cancer.

Transperineal versus transrectal multi-parametric magnetic resonance imaging fusion targeted prostate biopsy.

Objectives:To compare transperineal biopsies (TPBx) with transrectal ultrasound-guided biopsy (TRUSBx) in order to provide evidence, making clinicians able to select the appropriate biopsy approach under different conditions.Methods:A comparative prospective study, conducted in King Khalid University Hospital (KKUH) and King Faisal Specialist Hospital and Research Centre (KFSH&RC), Riyadh, Kingdom of Saudi Arabia, between March 2019 and February 2020. All patients with raised prostate-specific antigen or atypical digital rectal examination findings were subjected to multi-parametric magnetic resonance imaging (MRI). Those with positive findings were referred to targeted fusion- guided biopsy either TPBx or TRUSBx, randomly. Complication rate, cancer detection rate, and procedure time were recorded.Results:Transperineal biopsies and TRUSBx had an equivalent complication rate. However, both case detection rate and clinically significant cancer detection rate were significantly higher in TPBx versus TRUSBx (45.1% versus 29.1%, p=0.003; and 71.8% versus 43.7%, p=0.002; respectively). Transperineal biopsies was a longer procedure than TRUSBx (41.2±0.7 min versus 13±2.3 min, p=0.0001).Conclusion:No difference in complication rate was detected between the 2 procedures; however, TPBx was more effective for cancer detection in general and clinically significant cancer detection in particular.

Magnetic resonance imaging-guided stereotactic body radiotherapy for prostate cancer (mirage): a phase iii randomized trial

BackgroundStereotactic body radiotherapy (SBRT) is becoming increasingly used in treating localized prostate cancer (PCa), with evidence showing similar toxicity and efficacy profiles when compared with longer courses of definitive radiation. Magnetic resonance imaging (MRI)-guided radiotherapy has multiple potential advantages over standard computed tomography (CT)-guided radiotherapy, including enhanced prostate visualization (abrogating the need for fiducials and MRI fusion), enhanced identification of the urethra, the ability to track the prostate in real-time, and the capacity to perform online adaptive planning. However, it is unknown whether these potential advantages translate into improved outcomes. This phase III randomized superiority trial is designed to prospectively evaluate whether toxicity is lower after MRI-guided versus CT-guided SBRT.MethodsThree hundred men with localized PCa will be randomized in a 1:1 ratio to SBRT using CT or MRI guidance. Randomization will be stratified by baseline International Prostate Symptom Score (IPSS) (≤15 or > 15) and prostate gland volume (≤50 cc or > 50 cc). Five fractions of 8 Gy will be delivered to the prostate over the course of fourteen days, with or without hormonal therapy and elective nodal radiotherapy (to a dose of 5 Gy per fraction) as per the investigator’s discretion. The primary endpoint is the incidence of physician-reported acute grade ≥ 2 genitourinary (GU) toxicity (during the first 90 days after SBRT), as assessed by the CTCAE version 4.03 scale. Secondary clinical endpoints include incidence of acute grade ≥ 2 gastrointestinal (GI) toxicity, 5-year cumulative incidences of physician-reported late grade ≥ 2 GU and GI toxicity, temporal changes in patient-reported quality of life (QOL) outcomes, 5-year biochemical recurrence-free survival and the proportion of fractions of MRI-guided SBRT in which online adaptive radiotherapy is used.DiscussionThe MIRAGE trial is the first randomized trial comparing MRI-guided with standard CT-guided SBRT for localized PCa. The primary hypothesis is that MRI-guided SBRT will lead to an improvement in the cumulative incidence of acute grade ≥ 2 GU toxicity when compared to CT-guided SBRT. The pragmatic superiority design focused on an acute toxicity endpoint will allow an early comparison of the two technologies.Trial registrationClinicaltrials.gov identifier: NCT04384770. Date of registration: May 12, 2020.https://clinicaltrials.gov/ct2/show/NCT04384770Protocol versionVersion 2.1, Aug 28, 2020.

3D ultrasound guided navigation system with hybrid image fusion

A prototype of a navigation system to fuse two image modalities is presented. The standard inter-modality registration is replaced with a tracker-based image registration of calibrated imaging devices. Intra-procedure transrectal US (TRUS) images were merged with pre-procedure magnetic resonance (MR) images for prostate biopsy. The registration between MR and TRUS images was performed by an additional abdominal 3D-US (ab-3D-US), which enables replacing the inter-modal MR/TRUS registration by an intra-modal ab-3D-US/3D-TRUS registration. Calibration procedures were carried out using an optical tracking system (OTS) for the pre-procedure image fusion of the ab-3D-US with the MR. Inter-modal ab-3D-US/MR image fusion was evaluated using a multi-cone phantom for the target registration error (TRE) and a prostate phantom for the Dice score and the Hausdorff distance of lesions . Finally, the pre-procedure ab- 3D-US was registered with the TRUS images and the errors for the transformation from the MR to the TRUS were determined. The TRE of the ab-3D-US/MR image registration was 1.81 mm. The Dice-score and the Hausdorff distance for ab-3D-US and MR were found to be 0.67 and 3.19 mm. The Dice score and the Hausdorff distance for TRUS and MR were 0.67 and 3.18 mm. The hybrid navigation system showed sufficient accuracy for fusion guided biopsy procedures with prostate phantoms. The system might provide intra-procedure fusion for most US-guided biopsy and ablation interventions.

Prostate cancer detection by targeted prostate biopsy using the 3D Navigo system: a prospective study.

The 3D Navigo™ system is a magnetic resonance imaging (MRI) and transrectal ultrasound (TRUS) fusion device for prostate targeted biopsies (TB). Our aim was to evaluate the clinically significant prostate cancer (CSC) detection rate of TB using the 3D Navigo™ system. Patients who underwent TB with the 3D Navigo™ system in our center between June 2014 and May 2018 were prospectively included, excluding those who have previously received treatment for prostate cancer. A 3-Tesla MRI imaging was performed before biopsies; findings were reported according to the Prostate Imaging Reporting and Data System version 2 (PIRADS). CSC was defined by an ISUP score ≥ 2. 304 patients underwent TB. Median age was 66years (51-84). Median PSA was 7.75ng/ml (0.6-70.0). Median prostate volume was 45.0ml (15.9-221.7). PCa and CSC were found in 70.4% (214/304) and 47.7% (145/304) of the patients, respectively. The proportion of patients diagnosed with CSC among those with PCa was 67.8% (145/214). There was a significant risk of having a CSC in case of PIRADS score ≥ 4 and 5 (OR 5.0, 95% CI [2.7-9.2], P < 0.001; OR 3.2, 95% CI [1.8-5.5], P < 0.001). PIRADS score was an independent risk factor of having a CSC (OR 4.19, 95% CI [2.49-7.05], P < 0.001). There was no significant difference between pathological outcomes of TB and RP in paired analysis (P = 0.892). There was a correlation between TB and RP specimens for PCa detection (r = 0.60, P < 0.001). Detecting CSC with MRI-TRUS fusion targeted biopsies using the 3D Navigo™ system is feasible and safe. We found a positive correlation between TB and RP for ISUP scores.

Machine learning application in Glioma classification: review and comparison analysis

This paper simply presents a state of the art survey among the machine learning based approaches for the Glioma classification. As Glioma classification is a very challenging task in the field of medical science and this task is well addressed and taken by the fraternity of machine learning experts, who are working day and night to devise automated approaches that can automate this whole process of Glioma accurate classification from the various medical imaging modalities like Magnetic resonance imaging (MRI), Computed tomography (CT) etc. Although present machine learning techniques offers an opportunity to come up with a highly accurate and automated Glioma classification approach, by performing fusion among the various medical imaging modalities as well as utilizing the various features derived from the multi-modality medical imaging data. This paper also proposed an efficient and accurate automated approach of Glioma classification for the comparison analysis. This proposed approach is based on the use of hybrid ensemble learning model and hybrid feature extraction method, which relies on the Discrete wavelet Decomposition (DWD), Central pixel Neighbourhood Binary pattern (CNBP) and GLRLM (Gray level run length Matrix) methods in order to classify the Glioma (type of mostly diagnosed brain tumors) into Low grade Glioma and High grade Glioma from the fused MRI sequences. Improved eXtreme Gradient Boosting classifier is the hybrid ensemble learning model, which is used in this paper for the first time along with the proposed hybrid texture feature extraction method. Further this proposed approach is compared with the already existing state of the art approaches, which are based on the various machine learning classifiers like Support vector machine (SVM), K-Nearest neighbor (KNN), Naive Bayes (NB) etc. and conventional feature extraction methods in order to present a comprehensive and practical comparison study. The proposed approach is evaluated on the balanced large size local dataset consisting of MRI images of low and high grade Glioma collected from the various MRI centers located in Madhya Pradesh, India as well as on the popular global datasets like, BRATS 2013 and BRATS 2015 with various MRI fusion combinations (T1 + T1C + T2 + Flair, T1 + T1C + T2, T1 + T1C + Flair, T1C + T2 + Flair etc.). The proposed approach employing Improved eXtreme Gradient Boosting ensemble model offers highest accuracy of above 90% on the local dataset with the fusion of T1C + T2 + Flair MRI sequences.

Prostate Cancer Detection Using 3-D Shear Wave Elasticity Imaging

Transrectal ultrasound (TRUS) B-mode imaging provides insufficient sensitivity and specificity for prostate cancer (PCa) targeting when used for biopsy guidance. Shear wave elasticity imaging (SWEI) is an elasticity imaging technique that has been commercially implemented and is sensitive and specific for PCa. We have developed a SWEI system capable of 3-D data acquisition using a dense acoustic radiation force (ARF) push approach that leads to enhanced shear wave signal-to-noise ratio compared with that of the commercially available SWEI systems and facilitates screening of the entire gland before biopsy. Additionally, we imaged and assessed 36 patients undergoing radical prostatectomy using 3-D SWEI and determined a shear wave speed threshold separating PCa from healthy prostate tissue with sensitivities and specificities akin to those for multiparametric magnetic resonance imaging fusion biopsy. The approach measured the mean shear wave speed in each prostate region to be 4.8 m/s (Young's modulus E = 69.1 kPa) in the peripheral zone, 5.3 m/s (E = 84.3 kPa) in the central gland and 6.0 m/s (E = 108.0 kPa) for PCa with statistically significant (p < 0.0001) differences among all regions. Three-dimensional SWEI receiver operating characteristic analyses identified a threshold of 5.6 m/s (E = 94.1 kPa) to separate PCa from healthy tissue with a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under the curve (AUC) of 81%, 82%, 69%, 89% and 0.84, respectively. Additionally, a shear wave speed ratio was assessed to normalize for tissue compression and patient variability, which yielded a threshold of 1.11 to separate PCa from healthy prostate tissue and was accompanied by a substantial increase in specificity, PPV and AUC, where the sensitivity, specificity, PPV, NPV and AUC were 75%, 90%, 79%, 88% and 0.90, respectively. This work illustrates the feasibility of using 3-D SWEI data to detect and localize PCa and demonstrates the benefits of normalizing for applied compression during data acquisition for use in biopsy targeting studies.

Computer-aided diagnosis and regional segmentation of nasopharyngeal carcinoma based on multi-modality medical images.

Nasopharyngeal carcinoma (NPC) is a category of tumors with high incidence in head-and-neck (H&N) body region, and the diagnosis and treatment planning are usually conducted by radiologists manually, which is tedious, time-consuming and unrepeatable. In this paper, we integrated different stages of this process and proposed a computer-aided framework to realize automatic detection, tumor region and sub-region segmentation, and visualization of NPC, which are usually investigated separately in literatures. Multi-modality images are utilized in the framework. Firstly, NPC is detected by a convolutional neural network (CNN) on computed tomography (CT) scans. Then, NPC area is segmented from magnetic resonance imaging (MRI) images by using a multi-modality MRI fusion network. Thirdly, NPC sub-regions with different metabolic activities are divided on CT images of the same patient via an adaptive threshold algorithm. Finally, 3D surface model of NPC is generated for observing its shape, size, and location in the head region. The proposed method is compared with other algorithms by evaluation on the volumes and shapes of detected NPCs. Experiments are conducted on CT images of 130 NPC patients and 102 subjects without NPC and MRI images of 149 NPC patients, among which 52 subjects are overlapped with both CT and MRI images. The reference for evaluation is generated by three experienced radiologists. The results demonstrated that our utilized models outperform other strategies with detection accuracy 0.882 and Dice similarity coefficient 0.719 for NPC segmentation. Sub-region division and the 3D visualized models show great acceptability in clinical usage. The remarkable performance indicated the potential of our framework in alleviating workload of radiologist. Furthermore, the combined usage of multi-modality images is able to generate reliable segmentations of NPC area and sub-regions, which provide evidence to judge the heterogeneity among patients and guide the dose painting for radiation therapy.

Three-Dimensional Radiological Assessment of Ablative Margins in Hepatocellular Carcinoma: Pilot Study of Overlay Fused CT/MRI Imaging with Automatic Registration.

Simple SummaryRecent advances in fusion imaging technology have made it easier to visualize and estimate ablative margins. This study was conducted to assess the clinical feasibility of a computed tomography (CT)/magnetic resonance imaging (MRI) fusion application for evaluation of the ablative margin in radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Seventeen patients developed local tumor progressions (LTPs) due to wrong initial evaluations of technical success through a side-by-side comparison, and we reevaluated the ablative margins using the CT/MRI overlay fusion application. Eight patients were categorized into grade C (margin-zero ablation) and nine patients into grade D (existence of residual HCC). LTP occurred in re-graded C patients within 4 to 30.3 months (median, 14.3 months), and in re-graded D patients within 2.4 to 6.7 months (median, 4.2 months) (p = 0.006). Overlay fused CT/MRI imaging can allow us to evaluate HCC ablative margin three-dimensionally with high accuracy. Background: We investigate the feasibility of image fusion application for ablative margin assessment in radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) and possible causes for a wrong initial evaluation of technical success through a side-by-side comparison. Methods: A total of 467 patients with 1100 HCCs who underwent RFA were reviewed retrospectively. Seventeen patients developed local tumor progressions (LTPs) (median size, 1.0 cm) despite initial judgments of successful ablation referring to contrast-enhanced images obtained in the 24 h after ablation. The ablative margins were reevaluated radiologically by overlaying fused images pre- and post-ablation. Results: The initial categorizations of the 17 LTPs had been grade A (absolutely curative) (n = 5) and grade B (relatively curative) (n = 12); however, the reevaluation altered the response categories to eight grade C (margin-zero ablation) and nine grade D (existence of residual HCC). LTP occurred in eight patients re-graded as C within 4 to 30.3 months (median, 14.3) and in nine patients re-graded as D within 2.4 to 6.7 months (median, 4.2) (p = 0.006). Periablational hyperemia enhancements concealed all nine HCCs reevaluated as grade D. Conclusion: Side-by-side comparisons carry a risk of misleading diagnoses for LTP of HCC. Overlay fused imaging technology can be used to evaluate HCC ablative margin with high accuracy.

Diagnostic accuracy of three-dimensional-rotational angiography and heavily T2-weighted volumetric magnetic resonance fusion imaging for the diagnosis of spinal arteriovenous shunts

BackgroundSpinal arteriovenous shunts (SAVSs) are rare entities occurring in various areas, from the craniocervical junction to the sacral level. Recently, better understanding of SAVS angioarchitecture and elucidation of its pathogenesis...

Esmraldi: efficient methods for the fusion of mass spectrometry and magnetic resonance images

BackgroundMass spectrometry imaging (MSI) is a family of acquisition techniques producing images of the distribution of molecules in a sample, without any prior tagging of the molecules. This makes it a very interesting technique for exploratory research. However, the images are difficult to analyze because the enclosed data has high dimensionality, and their content does not necessarily reflect the shape of the object of interest. Conversely, magnetic resonance imaging (MRI) scans reflect the anatomy of the tissue. MRI also provides complementary information to MSI, such as the content and distribution of water.ResultsWe propose a new workflow to merge the information from 2D MALDI–MSI and MRI images. Our workflow can be applied to large MSI datasets in a limited amount of time. Moreover, the workflow is fully automated and based on deterministic methods which ensures the reproducibility of the results. Our methods were evaluated and compared with state-of-the-art methods. Results show that the images are combined precisely and in a time-efficient manner.ConclusionOur workflow reveals molecules which co-localize with water in biological images. It can be applied on any MSI and MRI datasets which satisfy a few conditions: same regions of the shape enclosed in the images and similar intensity distributions.