scholarly journals Safety of stereotactic laser ablations performed as treatment for glioblastomas in a conventional magnetic resonance imaging suite

2016 ◽  
Vol 41 (4) ◽  
pp. E7 ◽  
Author(s):  
Robert C. Rennert ◽  
Kate T. Carroll ◽  
Mir Amaan Ali ◽  
Thomas Hamelin ◽  
Leon Chang ◽  
...  
Keyword(s):  
Thermal Ablation ◽  
Tumor Recurrence ◽  
Wound Infections ◽  
Wild Type ◽  
Resonance Imaging ◽  
Isocitrate Dehydrogenase 1 ◽  
Conventional Mri ◽  
Stereotactic Device ◽  
Probe Insertion ◽  
Ablation Line

OBJECTIVE Stereotactic laser ablation (SLA) is typically performed in the setting of intraoperative MRI or in a staged manner in which probe insertion is performed in the operating room and thermal ablation takes place in an MRI suite. METHODS The authors describe their experience, in which SLA for glioblastoma (GBM) treatment was performed entirely within a conventional MRI suite using the SmartFrame stereotactic device. RESULTS All 10 patients with GBM (2 with isocitrate dehydrogenase 1 mutation [mIDH1] and 8 with wild-type IDH1 [wtIDH1]) were followed for > 6 months. One of these patients underwent 2 independent SLAs approximately 12 months apart. Biopsies were performed prior to SLA for all patients. There were no perioperative morbidities, wound infections, or unplanned 30-day readmissions. The average time for a 3-trajectory SLA (n = 3) was 436 ± 102 minutes; for a 2-trajectory SLA (n = 4) was 321 ± 85 minutes; and for a single-trajectory SLA (n = 4) was 254 ± 28 minutes. No tumor recurrence occurred within the blue isotherm line ablation zone, although 2 patients experienced recurrence immediately adjacent to the blue isotherm ablation line. Overall survival for the patient cohort averaged 356 days, with the 2 patients who had mIDH1 GBMs exhibiting the longest survival (811 and 654 days). CONCLUSIONS Multitrajectory SLA for treatment of GBM can be safely performed using the SmartFrame stereotactic device in a conventional MRI suite.

scholarly journals Assessment of Isocitrate Dehydrogenase 1 Genotype and Cell Proliferation in Gliomas Using Multiple Diffusion Magnetic Resonance Imaging

2021 ◽  
Vol 15 ◽  
Author(s):  
Yan Xie ◽  
Shihui Li ◽  
Nanxi Shen ◽  
Tongjia Gan ◽  
Shun Zhang ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Cell Proliferation ◽  
Diffusion Coefficient ◽  
Magnetic Resonance ◽  
Isocitrate Dehydrogenase ◽  
Diffusion Magnetic Resonance Imaging ◽  
Wild Type ◽  
Resonance Imaging ◽  
Isocitrate Dehydrogenase 1 ◽  
Ki 67

Objectives: To compare the efficacy of parameters from multiple diffusion magnetic resonance imaging (dMRI) for prediction of isocitrate dehydrogenase 1 (IDH1) genotype and assessment of cell proliferation in gliomas.Methods: Ninety-one patients with glioma underwent diffusion weighted imaging (DWI), multi-b-value DWI, and diffusion kurtosis imaging (DKI)/neurite orientation dispersion and density imaging (NODDI) on 3.0T MRI. Each parameter was compared between IDH1-mutant and IDH1 wild-type groups by Mann–Whitney U test in lower-grade gliomas (LrGGs) and glioblastomas (GBMs), respectively. Further, performance of each parameter was compared for glioma grading under the same IDH1 genotype. Spearman correlation coefficient between Ki-67 labeling index (LI) and each parameter was calculated.Results: The diagnostic performance was better achieved with apparent diffusion coefficient (ADC), slow ADC (D), fast ADC (D∗), perfusion fraction (f), distributed diffusion coefficient (DDC), heterogeneity index (α), mean diffusivity (MD), mean kurtosis (MK), and intracellular volume fraction (ICVF) for distinguishing IDH1 genotypes in LrGGs, with statistically insignificant AUC values from 0.750 to 0.817. In GBMs, no difference between the two groups was found. For IDH1-mutant group, all parameters, except for fractional anisotropy (FA) and D∗, significantly discriminated LrGGs from GBMs (P < 0.05). However, for IDH1 wild-type group, only ADC statistically discriminated the two (P = 0.048). In addition, MK has maximal correlation coefficient (r = 0.567, P < 0.001) with Ki-67 LI.Conclusion: dMRI-derived parameters are promising biomarkers for predicting IDH1 genotype in LrGGs, and MK has shown great potential in assessing glioma cell proliferation.

Systematic Analysis and Review of Magnetic Resonance Imaging (MRI) Reconstruction Techniques

2021 ◽  
Vol 16 ◽  
Author(s):  
Penta Anil Kumar ◽  
R. Gunasundari ◽  
R. Aarthi
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Optimization Technique ◽  
Motion Artifacts ◽  
Reconstruction Technique ◽  
Resonance Imaging ◽  
Research Gaps ◽  
Conventional Mri ◽  
Mri Reconstruction ◽  
Magnetic Resonance Imaging Mri

Background: Magnetic Resonance Imaging (MRI) plays an important role in the field of medical diagnostic imaging as it poses non-invasive acquisition and high soft-tissue contrast. However, the huge time is needed for the MRI scanning process that results in motion artifacts, degrades image quality, misinterpretation of data, and may cause uncomfortable to the patient. Thus, the main goal of MRI research is to accelerate data acquisition processing without affecting the quality of the image. Introduction: This paper presents a survey based on distinct conventional MRI reconstruction methodologies. In addition, a novel MRI reconstruction strategy is proposed based on weighted Compressive Sensing (CS), Penalty-aided minimization function, and Meta-heuristic optimization technique. Methods: An illustrative analysis is done concerning adapted methods, datasets used, execution tools, performance measures, and values of evaluation metrics. Moreover, the issues of existing methods and the research gaps considering conventional MRI reconstruction schemes are elaborated to obtain improved contribution for devising significant MRI reconstruction techniques. Results: The proposed method will reduce conventional aliasing artifacts problems, may attain lower Mean Square Error (MSE), higher Peak Signal-to-Noise Ratio (PSNR), and Structural SIMilarity (SSIM) index. Conclusion: The issues of existing methods and the research gaps considering conventional MRI reconstruction schemes are elaborated to devising an improved significant MRI reconstruction technique.

scholarly journals Can diffusion and T2 star-weighted magnetic resonance imaging aid in the diagnosis of ectopic endometrium?

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Mariam Raafat ◽  
Soha H. Talaat ◽  
Salma M. Abdelghaffar ◽  
Engy A. Ali
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Statistical Significance ◽  
P Value ◽  
Large Sample Size ◽  
Resonance Imaging ◽  
Conventional Mri ◽  
Patient Will ◽  
Magnetic Resonance Imaging Mri ◽  
Ectopic Endometrium

Abstract Background Endometriosis is a common gynecologic disorder characterized by the implantation of the endometrial tissue ectopically outside the endometrial cavity. It affects about 10% of females at the childbearing period and is estimated to be present up to 20–50% in women complaining of infertility. While laparoscopy is considered the mainstay for diagnosis, magnetic resonance imaging (MRI) is recognized as a useful tool for definitive diagnosis, pre-surgical planning, and determining whether the patient will require multi-specialty involvement. The aim of this study is to evaluate the performance of MRI with the addition of diffusion-weighted imaging (DWI) and T2 star (T2*) to conventional MRI, for the accurate assessment of ectopic endometrium. Results Endometriotic lesions that showed diffusion restriction on DWI were 80.7%, and 96.1% of the endometriotic lesions had signal voids on the T2*W sequence, whereas only 65.4% of the lesions had typical signal intensities on T1WI and T2WI. Diagnostic performance of the MRI examination was improved by the use of the diffusion sequence and better improved by the T2* sequence, compared to the conventional MR protocol sensitivity (SE) = 96.12% and specificity (SP) = 85.7% in T2*-weighted images, SE = 80.7% and SP = 71.4% in DWI, and SE = 65.4% and SP = 71.4% in conventional MRI. P value for conventional MRI was 0.1, which is of no statistical significance (p < 0.05). P value for DWI was 0.016, which is statistically significant (p < 0.05). P value for T2*WI was 0.001, which is more statistically significant (p < 0.05) and could be adequately correlated with laparoscopy. Conclusion DWI and T2* significantly increase MRI diagnostic accuracy by allowing the detection of the hemorrhagic character of the endometriotic lesions. Studies with a large sample size are needed to confirm that they can replace invasive laparoscopy for the diagnosis of endometriosis.

Evaluation of Radiofrequency Thermal Ablation Results in Inferior Turbinate Hypertrophies by Magnetic Resonance Imaging

2007 ◽  
Vol 117 (4) ◽  
pp. 623-627 ◽  
Author(s):  
Tarik Sapci ◽  
Canan Usta ◽  
M Fatih Evcimik ◽  
Ziya Bozkurt ◽  
Elcin Aygun ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Thermal Ablation ◽  
Inferior Turbinate ◽  
Resonance Imaging ◽  
Radiofrequency Thermal Ablation

Comparison of Diagnostic Accuracy of Magnetic Resonance Spectroscopy with Conventional Magnetic Resonance Imaging for Brain Tumors and Correlation with Histopathology as Gold Standard

2021 ◽  
Vol 15 (9) ◽  
pp. 4009-4011
Author(s):  
Saulat Sarfraz ◽  
Mahwish Farzana
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Brain Tumors ◽  
Diagnostic Accuracy ◽  
Gold Standard ◽  
Age Groups ◽  
Resonance Spectroscopy ◽  
Resonance Imaging ◽  
Conventional Mri

Background: In spite of recent advances in the use of diagnostic imaging modalities none of them has a hundred percent accuracy. So, misdiagnosis still occurs. Many trials are being done to evaluate the accuracy of these tools individually or in combination. The most useful investigation is MRI which broadly gives information of lesion as well its relationship with surrounding structures. While magnetic resonance spectroscopy further characterizes the lesion into benign or malignant. So this study is bit superior giving more details. By enlarge histopathology is gold standard for ultimate diagnosis. However these radiological investigations are extremely important for preoperative planning as well management of the lesion. In this study we compare the diagnostic accuracy of Magnetic Resonance Spectroscopy (MRS) with conventional MRI (Magnetic Resonance Imaging) sequences for diagnosis of brain tumors keeping histopathology as gold standard. Methods: The study was performed in 150 clinically suspected cases which were referred to Radiology Department from OPD, Indoor, Emergency and private sources from outside the hospital. Results: Majority 85(56.7%) were adult males and 65(43.3%) were adult females. The study was divided into two major age groups. There were 33cases (22%) with average age 20-35 years. The other age group 36-50 years had 40(26.7%) Majority of the cases 77(51.3%) were of average >50 years of age. The higher age groups showed a female dominance. Histopathology of 100(66.7%) cases confirmed positive and 50(33.3%) negative for MR Spectroscopy. On comparison of conventional MRI with contrast, and Histopathology it was observed that the sensitivity of MRI was 74.0% and the specificity 82.0%.The positive and negative predictive values gave a lower accuracy rate of 76.6%. Conclusion: The conclusion of our study is that MRS is a rigorous, non-invasive, safe and convenient imaging modality for the evaluation of brain tumors as compared to MRI. Keywords: Brain tumors, MRI, MRS, Histopathology

scholarly journals The Impact of IDH1 Mutation and MGMT Promoter Methylation on Recurrence-Free Interval in Glioblastoma Patients Treated With Radiotherapy and Chemotherapeutic Agents

2021 ◽  
Vol 27 ◽  
Author(s):  
Maher Kurdi ◽  
Nadeem Shafique Butt ◽  
Saleh Baeesa ◽  
Badrah Alghamdi ◽  
Yazid Maghrabi ◽  
...  
Keyword(s):  
Promoter Methylation ◽  
Tumor Recurrence ◽  
Dna Methyltransferase ◽  
Chemotherapeutic Agents ◽  
Idh1 Mutation ◽  
Treatment Modalities ◽  
Isocitrate Dehydrogenase 1 ◽  
Free Interval ◽  
Significant Difference ◽  
The Impact

The aim of this study is to investigate the relationship between isocitrate dehydrogenase-1 (IDH1) mutation and O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation with recurrence-free interval in glioblastoma patients treated with chemoradiotherapies. Clinical data were collected from 82 patients with totally resected glioblastoma and treated with adjuvant therapies from 2014 to 2019. IDH1 mutation was assessed by immunohistochemistry and MGMT promoter methylation was assessed by different sequencing methods. IDH1 mutation was present in 32 cases and 50 cases were IDH1 wildtype; 54 and 28 patients had unmethylated and methylated MGMT promoter, respectively, Of the 82 patients, 62 patients received chemoradiotherapy while 20 patients only received radiation. Approximately, 61% of patients had a tumor recurrence after 1 year, and 39% showed a recurrence before 1 year of treatment. There was no significant relationship between IDH1 mutation and MGMT promoter methylation (p-value = 0.972). Patients with IDH1 mutation and their age &lt;50 years showed a significant difference in recurrence-free interval (p-value = 0.014). Difference in recurrence-free interval was also statistically observed in patients with unmethylated MGMT promoter and treated with chemoradiotherapies (p-value = 0.031), by which they showed a late tumor recurrence (p-value = 0.016). This revealed that IDH1 mutation and MGMT methylation are independent prognostic factors in glioblastoma. Although IDH1-mutant glioblastomas showed late tumor recurrence in patients less than 50 years old, the type of treatment modalities may not show additional beneficial outcome. Patients with unmethylated MGMT and IDH1 mutation, treated with different chemoradiotherapies, showed a late tumor recurrence.

MAGNETIC RESONANCE IMAGING-GUIDED FOCUSED ULTRASOUND FOR THERMAL ABLATION IN THE BRAIN

Neurosurgery ◽  
2007 ◽  
Vol 60 (4) ◽  
pp. 593-600 ◽  
Author(s):  
Zvi R. Cohen ◽  
Jacob Zaubermann ◽  
Sagi Harnof ◽  
Yael Mardor ◽  
Dvora Nass ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Thermal Ablation ◽  
Focused Ultrasound ◽  
Resonance Imaging ◽  
The Brain

scholarly journals Inhibitor potency varies widely among tumor-relevant human isocitrate dehydrogenase 1 mutants

2018 ◽  
Vol 475 (20) ◽  
pp. 3221-3238 ◽  
Author(s):  
Diego Avellaneda Matteo ◽  
Grace A. Wells ◽  
Lucas A. Luna ◽  
Adam J. Grunseth ◽  
Olga Zagnitko ◽  
...  
Keyword(s):  
Isocitrate Dehydrogenase ◽  
Resistance Mutation ◽  
Poor Response ◽  
Fold Increase ◽  
Structural Features ◽  
Low Grade ◽  
Wild Type ◽  
Isocitrate Dehydrogenase 1 ◽  
Dynamics Simulations ◽  
Mutant Idh1

Mutations in isocitrate dehydrogenase 1 (IDH1) drive most low-grade gliomas and secondary glioblastomas and many chondrosarcomas and acute myeloid leukemia cases. Most tumor-relevant IDH1 mutations are deficient in the normal oxidization of isocitrate to α-ketoglutarate (αKG), but gain the neomorphic activity of reducing αKG to D-2-hydroxyglutarate (D2HG), which drives tumorigenesis. We found previously that IDH1 mutants exhibit one of two reactivities: deficient αKG and moderate D2HG production (including commonly observed R132H and R132C) or moderate αKG and high D2HG production (R132Q). Here, we identify a third type of reactivity, deficient αKG and high D2HG production (R132L). We show that R132Q IDH1 has unique structural features and distinct reactivities towards mutant IDH1 inhibitors. Biochemical and cell-based assays demonstrate that while most tumor-relevant mutations were effectively inhibited by mutant IDH1 inhibitors, R132Q IDH1 had up to a 16 300-fold increase in IC50 versus R132H IDH1. Only compounds that inhibited wild-type (WT) IDH1 were effective against R132Q. This suggests that patients with a R132Q mutation may have a poor response to mutant IDH1 therapies. Molecular dynamics simulations revealed that near the NADP+/NADPH-binding site in R132Q IDH1, a pair of α-helices switches between conformations that are more wild-type-like or more mutant-like, highlighting mechanisms for preserved WT activity. Dihedral angle changes in the dimer interface and buried surface area charges highlight possible mechanisms for loss of inhibitor affinity against R132Q. This work provides a platform for predicting a patient's therapeutic response and identifies a potential resistance mutation that may arise upon treatment with mutant IDH inhibitors.

Anatomical location differences between mutated and wild-type isocitrate dehydrogenase 1 in low-grade gliomas

2017 ◽  
Vol 127 (10) ◽  
pp. 873-880 ◽  
Author(s):  
Jinhua Yu ◽  
Zhifeng Shi ◽  
Chunhong Ji ◽  
Yuxi Lian ◽  
Yuanyuan Wang ◽  
...  
Keyword(s):  
Isocitrate Dehydrogenase ◽  
Anatomical Location ◽  
Low Grade ◽  
Wild Type ◽  
Isocitrate Dehydrogenase 1 ◽  
Low Grade Gliomas
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