mri imaging
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10.29007/pzv9 ◽  
2022 ◽  
Author(s):  
Tran Hong Duyen Trinh ◽  
Thi Hong Thuy Le ◽  
Minh Tri Huynh

Low back pain is a common disease. A common cause of this problem is a herniated disc in the lumbar spine. Lumbar disc herniation represents the displacement of the disc (annular fibrosis or medullary nuclei). While most cases, the pain will disappear in a few days to a few weeks; however, it can last for three months or more. Detection and diagnosis are the two most important tasks in a computer-aided diagnostic system. In this article, we use images taken from the results of the MRI imaging of the patient. Through the use of image inversion to highlight the position of degenerative discs. This result wishes to provide a simple and inexpensive diagnostic image processing method to help doctors quickly determine the degree of disc herniation, the status of lumbar discs, they can give the appropriate treatment to the patient.


2022 ◽  
Vol 8 ◽  
Author(s):  
Man Sun ◽  
Ping Xu ◽  
Gen Zou ◽  
Jianzhang Wang ◽  
Libo Zhu ◽  
...  

Objective: To determine whether endometrioma recurrence is closely related to the presence of extrinsic adenomyosis, which was demonstrated by magnetic resonance imaging (MRI).Design: Observational crosssectional study involving patients with the recurrence of ovarian endometrioma (OMA). Correlations of endometrioma recurrence and adenomyosis subtypes shown by MRI were analyzed.Method: Between January 2018 and December 2020, a total of 233 patients with recurrence of OMA after ovarian cystectomy were administered for surgery at our institution. All patients were divided into subtype II (Group A), subtype I+IV (Group B), and nonadenomyosis (Group C) groups at preoperative MRI imaging. The correlations of endometrioma recurrence with clinical features, imaging appearance, and surgical findings were retrospectively analyzed.Results: We found 112 (48.07%) patients of endometrioma recurrence combined with subtype II adenomyosis, 8 (3.43%) subtype I adenomyosis, 47 (20.17%) subtype IV adenomyosis, 66 (28.32%) nonadenomyosis. The mean time of OMA recurrence (44.28 ± 8.37, vs. 63.96 ± 10.28, vs. 69.36 ± 9.34 mon), rate of pain symptoms (85.71, vs. 69.10, vs. 18.18%), and primary infertility (31.25, vs. 14.55, vs. 10.77%) were higher in Group A. Uterine volume (257.37± 42.61, vs. 203.14 ± 33.52, vs. 100.85 ± 26.67 cm3), and mean OMA size (4.97 ± 2.25, vs. 4.36 ± 2.38, vs. 4.46 ± 2.70 cm) were significantly larger in Group A. The rate of DIE (83.93, vs. 45.45, vs. 40.91%), the number of DIE (3.6 ± 1.8 vs. 2.3 ± 1.5 vs. 2.2 ± 1.3), the mean total revised American Society for Reproductive Medicine score (rASRM, 103.14 ± 23.89 vs. 74.23 ± 16.72 vs. 36.51 ± 14.23) were significantly higher in Group A. After a multiple logistic regression analysis, extrinsic adenomyosis (OR 2.5, 95% CI 1.2–3.4), DIE lesions (OR 2.1, 95% CI 1.4–2.8), and primary infertility (OR 1.8, 95% CI 1.3–4.3) were significantly associated with early recurrence (in 3-year) of OMA.Conclusions: Extrinsic adenomyosis was associated with postoperative recurrence of OMA. In addition, a pathogenic link between extrinsic adenomyosis and pelvic endometriosis needs to be clarified.


2022 ◽  
Vol 12 (1) ◽  
pp. 89
Author(s):  
Xuan Cao ◽  
Fang Yang ◽  
Jingyi Zheng ◽  
Xiao Wang ◽  
Qingling Huang

Background: Depression is a prominent and highly prevalent nonmotor feature in patients with Parkinson’s disease (PD). The neural and pathophysiologic mechanisms of PD with depression (DPD) remain unclear. The current diagnosis of DPD largely depends on clinical evaluation. Methods: We proposed a new family of multinomial tensor regressions that leveraged whole-brain structural magnetic resonance imaging (MRI) data to discriminate among 196 non-depressed PD (NDPD) patients, 84 DPD patients, 200 healthy controls (HC), and to assess the special brain microstructures in NDPD and DPD. The method of maximum likelihood estimation coupled with state-of-art gradient descent algorithms was used to predict the individual diagnosis of PD and the development of DPD in PD patients. Results: The results reveal that the proposed efficient approach not only achieved a high prediction accuracy (0.94) with a multi-class AUC (0.98) for distinguishing between NDPD, DPD, and HC on the testing set but also located the most discriminative regions for NDPD and DPD, including cortical regions, the cerebellum, the brainstem, the bilateral basal ganglia, and the thalamus and limbic regions. Conclusions: The proposed imaging technique based on tensor regression performs well without any prior feature information, facilitates a deeper understanding into the abnormalities in DPD and PD, and plays an essential role in the statistical analysis of high-dimensional complex MRI imaging data to support the radiological diagnosis of comorbidity of depression with PD.


Author(s):  
Kanagasabai Kamalasekar ◽  
Reddy Ravikanth

AbstractThe first carpometacarpal (CMC) joint consists of seven ligaments. The magnetic resonance imaging (MRI) examination of the first CMC joint should be performed in a high field 1.5/3 T MRI with a dedicated hand coil for high-resolution images. Degeneration of anterior oblique ligament (AOL) is the most important cause for the development of osteoarthritis of first CMC joint. Since the AOL undergoes a predictable pattern of alteration at its metacarpal attachment as degeneration proceeds, MRI imaging can provide an accurate assessment of this ligament.


2022 ◽  
Vol 23 (2) ◽  
pp. 679
Author(s):  
Brandon M. Bordeau ◽  
Joseph Ryan Polli ◽  
Ferdinand Schweser ◽  
Hans Peter Grimm ◽  
Wolfgang F. Richter ◽  
...  

The prediction of monoclonal antibody (mAb) disposition within solid tumors for individual patients is difficult due to inter-patient variability in tumor physiology. Improved a priori prediction of mAb pharmacokinetics in tumors may facilitate the development of patient-specific dosing protocols and facilitate improved selection of patients for treatment with anti-cancer mAb. Here, we report the use of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), with tumor penetration of the contrast agent gadobutrol used as a surrogate, to improve physiologically based pharmacokinetic model (PBPK) predictions of cetuximab pharmacokinetics in epidermal growth factor receptor (EGFR) positive xenografts. In the initial investigations, mice bearing Panc-1, NCI-N87, and LS174T xenografts underwent DCE-MRI imaging with the contrast agent gadobutrol, followed by intravenous dosing of an 125Iodine-labeled, non-binding mAb (8C2). Tumor concentrations of 8C2 were determined following the euthanasia of mice (3 h–6 days after 8C2 dosing). Potential predictor relationships between DCE-MRI kinetic parameters and 8C2 PBPK parameters were evaluated through covariate modeling. The addition of the DCE-MRI parameter Ktrans alone or Ktrans in combination with the DCE-MRI parameter Vp on the PBPK parameters for tumor blood flow (QTU) and tumor vasculature permeability (σTUV) led to the most significant improvement in the characterization of 8C2 pharmacokinetics in individual tumors. To test the utility of the DCE-MRI covariates on a priori prediction of the disposition of mAb with high-affinity tumor binding, a second group of tumor-bearing mice underwent DCE-MRI imaging with gadobutrol, followed by the administration of 125Iodine-labeled cetuximab (a high-affinity anti-EGFR mAb). The MRI-PBPK covariate relationships, which were established with the untargeted antibody 8C2, were implemented into the PBPK model with considerations for EGFR expression and cetuximab-EGFR interaction to predict the disposition of cetuximab in individual tumors (a priori). The incorporation of the Ktrans MRI parameter as a covariate on the PBPK parameters QTU and σTUV decreased the PBPK model prediction error for cetuximab tumor pharmacokinetics from 223.71 to 65.02%. DCE-MRI may be a useful clinical tool in improving the prediction of antibody pharmacokinetics in solid tumors. Further studies are warranted to evaluate the utility of the DCE-MRI approach to additional mAbs and additional drug modalities.


2022 ◽  
Vol 12 ◽  
Author(s):  
Nahid Tabibzadeh ◽  
Anne-Laure Faucon ◽  
Emmanuelle Vidal-Petiot ◽  
Fidéline Serrano ◽  
Lisa Males ◽  
...  

Objectives: Early kidney damage during lithium treatment in bipolar disorder is still hypothetical. We aimed at identifying the determinants of a decreased measured glomerular filtration rate (mGFR) and the accuracy of kidney MRI imaging in its detection.Methods: In this cross-sectional cohort study, 217 consecutive lithium-treated patients underwent mGFR and kidney MRI with half-Fourier turbo spin-echo and Single-shot with long echo time sequences.Results: Median age was 51 [27–62] years, and median lithium treatment duration was 5 [2–14] years. 52% of patients had a stage 2 CKD. In multivariable analysis, the determinants of a lower mGFR were a longer lithium treatment duration (β −0.8 [−1; −0.6] ml/min/1.73 m2 GFR decrease for each year of treatment), a higher age (β −0.4 [−0.6; −0.3] ml/min/1.73 m2 for each year of age, p < 0.001), albuminuria (β −3.97 [−6.6; −1.3], p = 0.003), hypertension (β −6.85 [−12.6; −1.1], p = 0.02) and hypothyroidism (β −7.1 [−11.7; −2.5], p = 0.003). Serum lithium concentration was not associated with mGFR. Renal MRI displayed renal microcyst(s) in 51% of patients, detected as early as 1 year after lithium treatment initiation. mGFR and lithium treatment duration were strongly correlated in patients with microcyst(s) (r = −0.64, p < 0.001), but not in patients with no microcysts (r = −0.24, p = 0.09). The presence of microcysts was associated with the detection of an mGFR <45 ml/min/1.73 m2 (AUC 0.893, p < 0.001, sensitivity 80%, specificity 81% for a cut-off value of five microcysts).Conclusion: Lithium treatment duration and hypothyroidism strongly impacted mGFR independently of age, especially in patients with microcysts. MRI might help detect early lithium-induced kidney damage and inform preventive strategies.


2022 ◽  
Vol 12 (1) ◽  
pp. 77
Author(s):  
Sukhdeep Singh Bal ◽  
Fan Pei Gloria Yang ◽  
Yueh-Feng Sung ◽  
Ke Chen ◽  
Jiu-Haw Yin ◽  
...  

Background: Diagnosis and timely treatment of ischemic stroke depends on the fast and accurate quantification of perfusion parameters. Arterial input function (AIF) describes contrast agent concentration over time as it enters the brain through the brain feeding artery. AIF is the central quantity required to estimate perfusion parameters. Inaccurate and distorted AIF, due to partial volume effects (PVE), would lead to inaccurate quantification of perfusion parameters. Methods: Fifteen patients suffering from stroke underwent perfusion MRI imaging at the Tri-Service General Hospital, Taipei. Various degrees of the PVE were induced on the AIF and subsequently corrected using rescaling methods. Results: Rescaled AIFs match the exact reference AIF curve either at peak height or at tail. Inaccurate estimation of CBF values estimated from non-rescaled AIFs increase with increasing PVE. Rescaling of the AIF using all three approaches resulted in reduced deviation of CBF values from the reference CBF values. In most cases, CBF map generated by rescaled AIF approaches show increased CBF and Tmax values on the slices in the left and right hemispheres. Conclusion: Rescaling AIF by VOF approach seems to be a robust and adaptable approach for correction of the PVE-affected multivoxel AIF. Utilizing an AIF scaling approach leads to more reasonable absolute perfusion parameter values, represented by the increased mean CBF/Tmax values and CBF/Tmax images.


Author(s):  
Aanisa Gulzar ◽  
Nowsheena Ayoub ◽  
Jaffar Farooq Mir ◽  
Amer M. Alanazi ◽  
M. A. Shah ◽  
...  

AbstractHerein we report synthesis of hematite (α-Fe2O3) nanorods by calcinating hydrothermally synthesized goethite nanorods at 5000C. The structural, optical and MRI imaging guided cancer therapeutic properties of fabricated nanorods have been discussed in this manscript. FESEM and TEM imaging techniques were used to confirm the nanorod like morphology of as prepared materials. As we know that Fe2O3 nanorods with size in the range of 25–30 nm exhibit super magnetism. After coating with the PEG, the as prepared nanorods can be used as T2 MR imaging contrast agents. An excellent T2 MRI contrast of 38.763 mM–1s–1 achieved which is highest reported so far for α-Fe2O3. Besides the as prepared nanorods display an excellent photothermal conversion efficiency of 39.5% thus acts as an excellent photothermal therapeutic agent. Thus, we envision the idea of testing our nanorods for photothermal therapy and MR imaging application both in vitro and in vivo, achieving an excellent T2 MRI contrast and photothermal therapy effect with as prepared PEGylated nanorods.


2022 ◽  
Vol Volume 16 ◽  
pp. 8465-8483
Author(s):  
Anna Kastelik-Hryniewiecka ◽  
Pawel Jewula ◽  
Karolina Bakalorz ◽  
Gabriela Kramer-Marek ◽  
Nikodem Kuźnik
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