scholarly journals A quick guide to safety and compatibility of passive implants and devices in an MR environment

2004 ◽  
Vol 8 (2) ◽  
pp. 6 ◽  
Author(s):  
D.J. Kotze ◽  
C. De Vries
Keyword(s):  
Resonance Imaging ◽  
Electrical Currents ◽  
Additional Risk ◽  
Metal Implants ◽  
Passive Devices ◽  
Number Of Patients ◽  
Magnetic Resonance Imaging Mri ◽  
Mr Safe ◽  
Intended Use

An increasing number of patients with metal implants are being referred for magnetic resonance imaging (MRI) investigations. Implants and devices may be divided into two groups, namely active and passive. This article will focus on passive devices. A device is MR-safe when it is used in the MR environment, but presents no additional risk to the patient or other individuals, although the quality of diagnostic information may be affected. MR procedures may be contraindicated due to various interactions between the MR environment and medical devices, which include torque, translational force, heating, induced electrical currents, magnetic field interactions, artefacts, and misrepresentation. Therefore, before deciding whether any object is MRsafe/ compatible, the intended use and the possible retaining mechanisms must be considered.

scholarly journals A study of the sensitivity and specificity of the Magnetic Resonance Imaging (MRI) technique used in the diagnosis of endometriosis versus the intraoperative appearance considered the reference standard in the diagnosis of endometriosis

2021 ◽  
Vol 28 (1) ◽  
pp. 55-61
Author(s):  
Alexandra RADU ◽  
◽  
Elvira BRATILA ◽  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Sensitivity And Specificity ◽  
Reference Standard ◽  
Resonance Imaging ◽  
First Line ◽  
Magnetic Resonance Imaging Mri ◽  
Asymptomatic Women ◽  
Bladder Invasion

Endometriosis is a gynecological pathology with chronic symptoms, which negatively affects the patient’s quality of life. The prevalence of endometriosis in asymptomatic women is between 2% and 50%, depending on the populations studied and the method of diagnosis. The severity of the symptoms as well as the probability of diagnosing endometriosis increases with age9. Because endometriosis is a gynecological condition with a nonspecific clinical picture, sometimes even asymptomatic, imaging technology can be considered the first line of diagnosis for this pathology. The main objective of this study is to evaluate the sensitivity and specificity of nuclear magnetic resonance imaging (MRI) used in the diagnosis of endometriotic lesions depending on their location, and compare the results obtained with the intraoperative appearance considered a reference standard in the diagnosis of endometriosis. Our study revealed the highest specificity for MRI in the case of endometriotic bladder invasion, respectively the highest sensitivity for endometriotic rectal nodules.

Strength, Size, and Muscle Quality in the Upper Arm following Unilateral Training in Younger and Older Males and Females

2009 ◽  
Vol 2 ◽  
pp. CMAMD.S1180 ◽  
Author(s):  
Leah C. Tanton ◽  
Thomas A. Cappaert ◽  
Paul M. Gordon ◽  
Robert F. Zoeller ◽  
Theodore J. Angelopoulos ◽  
...  
Keyword(s):  
Muscle Quality ◽  
Resonance Imaging ◽  
Age And Gender ◽  
Males And Females ◽  
Older Subjects ◽  
Magnetic Resonance Imaging Mri ◽  
And Gender ◽  
Unilateral Training ◽  
Older Males

Purpose To assess strength, size, and muscle quality differences between younger and older males and females in response to training. Methods The bicep and tricep of the non-dominant arm were trained for twelve weeks in younger and older males and females (n = 41). The bicep of both arms were assessed pre and post for muscle strength using one-repetition maximum (1 RM) testing, and size using magnetic resonance imaging (MRI). Results Strength (p < 0.05), mCSA (p < 0.05), and 1 RM MQ (p < 0.00) increased in response to training in all subjects regardless of age or gender. Younger and older subjects had similar increases in strength (45.49 ± 15.30% vs. 42.67 ± 26.67% respectively), mCSA (16.22 ± 7.98% vs. 19.17 ± 6.19% respectively), and 1RM MQ (25.73 ± 15.76 vs. 19.67 ± 20.66 respectively). Women increased their strength (55.59 ± 19.45% vs. 32.87 ± 15.66% p < 0.00 respectively), size (20.36 ± 6.29% vs. 14.72 ± 7.28% p < 0.02 respectively), and 1 RM MQ (29.74 ± 18.33% vs. 16.30 ± 15.59% p <.02) more than men. In comparing age and gender, younger females increased their strength more than older males (56.42 ± 12.92% vs. 29.17 ± 21.8% p <.02 respectively). Older females also increased their strength more than older males (54.68 ± 25.73 vs. 29.17 ± 21.80% respectively). Younger females increased their 1 RM MQ more than older males (.18 ± .08 kg/cm vs. .06 ± .08 kg/cm p <.02 respectively). Conclusion Strength and mCSA increases similarly in older and younger subjects. However, the overall strength and quality of the muscle seems to improve more in women than in men.

Inter-Observer Variability of Vaginal Wall Segmentation From MRI: A Statistical Shape Analysis Approach

2015 ◽  
Author(s):  
Deanna C. Easley ◽  
Prahlad G. Menon ◽  
Pamela A. Moalli ◽  
Steven D. Abramowitch
Keyword(s):  
Shape Matching ◽  
Pelvic Floor Disorders ◽  
Pelvic Organ ◽  
Vaginal Wall ◽  
Resonance Imaging ◽  
Inter Observer Variability ◽  
Statistical Shape ◽  
Mri Scans ◽  
Magnetic Resonance Imaging Mri

Pelvic floor disorders such as Pelvic Organ Prolapse (POP) negatively impact the health and quality of life of millions of women worldwide. POP is characterized by the descent of the pelvic organs into the vagina due to compromised connective tissue support, resulting in discomfort and urinary/fecal incontinence. Magnetic Resonance Imaging (MRI) has been used to aid in the quantification of these anatomical changes, however the inter- and intra-observer repeatability necessary to make reliable conclusions about changes in anatomical positioning is questioned using current methods. The aim of this study was to quantify the degree of variability produced from inter-observer manual tracings of the vagina from MRI scans using a statistical shape matching approach.

scholarly journals Incidence of intraspinal abnormalities in congenital scoliosis: a systematic review and meta-analysis

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Xudong Wang ◽  
Yangke Yu ◽  
Ningning Yang ◽  
Lei Xia
Keyword(s):  
Systematic Review ◽  
Meta Analysis ◽  
Tethered Cord ◽  
Congenital Scoliosis ◽  
Cochrane Library ◽  
Resonance Imaging ◽  
R Software ◽  
Dural Ectasia ◽  
Magnetic Resonance Imaging Mri

Abstract Objective This is the first systematic review and meta-analysis on the overall incidence of intraspinal abnormalities in patients with congenital scoliosis (CS) and potential influencing factors. Methods We searched three large electronic databases (PubMed, EMBASE, and Cochrane Library) for potentially relevant studies. The quality of the included studies was assessed independently by two authors using the Methodological Index for Non-Randomized Studies (MINORS) criteria. Data on the number of CS patients, number of CS patients with intraspinal abnormalities, sex of the patients, and CS types were extracted from the included studies. R software was used to pool and analyze all the extracted data. Results This meta-analysis included 10 articles, and 671 of 1863 CS patients undergoing magnetic resonance imaging (MRI) examinations were identified to have intraspinal abnormalities. The overall incidence of intraspinal abnormalities in the patients with CS was 37% (95% CI, 29–45%). Diastematomyelia was the most common intraspinal abnormality and was detected in 45.60% of the patients with intraspinal abnormalities (306/671). The remaining intraspinal abnormalities included syringomyelia (273/671, 40.69%), tethered cord (190/671, 28.32%), low conus (58/671, 8.64%), intraspinal mass (39/671, 5.81%), Chiari malformation (32/671, 4.77%), fatty filum (27/671, 4.02%), spina bifida (occulta excluded) (17/671, 2.53%), tumor (17/671, 2.53%), cyst (12/671, 1.79%), syringomyelus (4/671, 0.60%), dural ectasia (1/671, 0.15%), and undiagnosed cord MRI hyperintensity (1/671, 0.15%). The patient’s sex and CS type were not factors that affected the incidence of intraspinal abnormalities in CS patients (all P > 0.05). Conclusions This meta-analysis revealed that the overall incidence of intraspinal abnormalities detected by MRI in CS patients was 37%. Diastematomyelia was the most common intraspinal abnormality. The patient’s sex and CS type were not factors that affected the incidence of intraspinal abnormalities in CS patients.

scholarly journals Effectiveness of Bilateral Inferior Petrosal Sinuses Sampling in Tumor Lateralization: Intraoperative Findings and Postoperative Results

2017 ◽  
Vol 78 (06) ◽  
pp. 506-511 ◽  
Author(s):  
Oscar Feo-Lee ◽  
Manuel Giraldo-Grueso ◽  
Juan Puentes ◽  
Pablo Harker
Keyword(s):  
Prediction Accuracy ◽  
Resonance Imaging ◽  
Postoperative Results ◽  
Inferior Petrosal Sinus Sampling ◽  
Number Of Patients ◽  
Remission Rates ◽  
Macroscopic Lesion ◽  
Biochemical Remission ◽  
Magnetic Resonance Imaging Mri ◽  
Abnormal Tissue

Object Diagnosis and treatment of Cushing's disease (CD) is a demanding endeavor. We evaluated the effectiveness of inferior petrosal sinus sampling (IPSS) in preoperative tumor lateralization and surgical outcomes. Methods Fifty-two consecutive patients with CD and normal magnetic resonance imaging (MRI) were enrolled between 2009 and 2015. Selective catheterization of petrosal sinuses for IPSS was performed. All patients underwent microsurgical dissection, and if a lesion was found, underwent lesion resection. Demographic, biochemical, and intraoperative findings were prospectively collected and reviewed 6 and 12 months postoperatively. Results Forty-five patients (86.4%) had clear lateralization while seven patients had bilateral elevation. Twenty-two patients (42%) were found to have a macroscopic lesion, defined as an abnormal tissue during microsurgical dissection, which was thus resected. No patient had a lesion larger than 4 mm. Eighty-one percent of patients had the lesion where IPSS had been predicted. Hemi-hypophysectomy was performed on twenty-eight patients based on IPSS findings, since no lesion was found. Eighty-six percent of patients with lesion resection had biochemical remission by 12 months. Biochemical remission was documented in 78 and 71% of patients who underwent hemi-hypophysectomy by 6 and 12 months, respectively. Conclusion With careful microsurgical dissection, a macroscopic lesion could be found in a significant number of patients with normal MRI. When no lesion was found, we recommend performing a hemi-hypophysectomy based on IPSS findings, since prediction accuracy was high and remission rates were significant.

scholarly journals Is it necessary to remove intrapapillary ducts in therapeutic mammary adenectomies for breast cancer?

Mastology ◽  
2020 ◽  
Vol 30 (Suppl 1) ◽  
Author(s):  
Rebeca Neves Heinzen ◽  
Alfredo Carlos Simões Dornellas de Barros ◽  
Filomena Marino Carvalho ◽  
Cristiane da Costa Brandeia Abrahao Nimir ◽  
Alfredo Luiz Jacomo
Keyword(s):  
Breast Cancer ◽  
Ductal Carcinoma In Situ ◽  
Carcinoma In Situ ◽  
Ductal Carcinoma ◽  
Glandular Tissue ◽  
Resonance Imaging ◽  
Areola Complex ◽  
Number Of Patients ◽  
Magnetic Resonance Imaging Mri

Introduction: The nipple-areola complex (NAC) has glandular tissue in intrapapillary ducts (IPDs). When the NAC is preserved during mammary adenectomies (MA) for the treatment of breast cancer (BC), this glandular tissue, which is a potential focus of tumor residues, remains. Objective: To estimate the frequency of neoplastic development in IPDs among BC patients treated with MA. Method: After the MA and with evidence of free retroareolar margin through intraoperative examination, the nipple was inverted, and its central portion, where mammary ducts are located, removed. A pointed-tip scalpel was used, preserving a tissue rim of 1.0 to 2.0 mm. The analysis involved 219 cases submitted to this type of surgery in the Clínica Professor Alfredo Barros. In all patients, the distance tumor-NAC was ≥2.0 cm, according to magnetic resonance imaging (MRI). The intrapapillary tissue removed was sent for microscopic examination of sections embedded in paraffin. Results: We found 4 cases of ductal carcinoma in situ (none infiltrating) in IPDs (1.19%). Considering only the 217 cases with free retroareolar margin in the definitive examination, the number of patients with ductal carcinoma in situ in IPDs decreased to 2 (0.9%). Conclusion: IPDs are rarely involved in selected cases of MA (distance tumor-NAC≥2.0 cm on MRI and free retroareolar margin). Ideally, they should be removed, especially when the intent is avoiding radiotherapy.

scholarly journals A Review on Edge Detection on Osteogenesis Imperfecta (OI) Image using Fuzzy Logic

2021 ◽  
Vol 2071 (1) ◽  
pp. 012040
Author(s):  
Muhammad Zainul Arif Ahmad Zaki ◽  
Mohd Hanafi Mat Som ◽  
Haniza Yazid ◽  
Khairul Salleh Basaruddin ◽  
Shafriza Nisha Basah ◽  
...  
Keyword(s):  
Fuzzy Logic ◽  
Edge Detection ◽  
Osteogenesis Imperfecta ◽  
Poor Quality ◽  
Medical Doctors ◽  
Resonance Imaging ◽  
Clinical Images ◽  
Bone Disorder ◽  
Magnetic Resonance Imaging Mri

Abstract Osteogenesis Imperfecta (OI) is a bone disorder that causes bone to be brittle and easy to fracture. The patient suffered from this disease will have poor quality of life. Simulation on the bone fracture risk would help medical doctors to make decision in their diagnosis. Detection of edges from the OI images is very important as it helps radiologist to segmentize cortical and cancellous bone to make a good 3D bone model for analysis. The purpose of this paper is to review the fundamentals of fuzzy logic in edge detection of OI bone as it is yet to be implemented. Several fuzzy logic concepts are reviewed by previous studies which include fuzziness, membership functions and fuzzy sets regarding digital images. The OI images were produced by modalities such as Magnetic Resonance Imaging (MRI), Ultrasound, or Computed Tomography (CT). In summary, researchers from the reviewed papers concluded that fuzzy logic can be implemented to detect edges in noisy clinical images.

scholarly journals CORRELATION OF LUMBAR FORAMINAL STENOSIS DEGREE ON SAGITTAL MRI WITH JOABPEQ (JAPANESE ORTHOPAEDIC ASSOCIATION BACKPAIN QUESTIONNAIRE) AND ODI (OSWESTRY DISABILITY INDEX) ON LUMBAR FORAMINAL STENOSIS L5-S1 PATIENTS

Biomedika ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 68-73
Author(s):  
Bagas Widhiarso ◽  
Anggita Tri Yurisworo ◽  
Andhi Prijosedjati ◽  
Pamudji Utomo ◽  
Handry Tri Handojo
Keyword(s):  
Quality Of Life ◽  
Magnetic Resonance Imaging ◽  
Oswestry Disability Index ◽  
Japanese Orthopaedic Association ◽  
Foraminal Stenosis ◽  
Resonance Imaging ◽  
Lumbar Foraminal Stenosis ◽  
Pain Evaluation ◽  
Magnetic Resonance Imaging Mri

Lumbar Foraminal Stenosis (LFS) dapat secara signifikan mengurangi fungsi dan kualitas hidup pasien dan Magnetic Resonance Imaging (MRI) adalah alat pendukung yang umum digunakan untuk mengukur beratnya stenosis. Lee score umumnya digunakan untuk mengukur derajat LFS pada MRI sagital. Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) dan Oswestry Disability Index (ODI) digunakan untuk menilai disabilitas dan skor fungsional pada pasien LFS. Penelitian ini bertujuan untuk mengetahui korelasi antara derajat LFS pada MRI sagital dengan kualitas hidup pada pasien dengan LFS. Penelitian ini merupakan penelitian analitik observasional yang melibatkan 25 pasien dengan gejala klinis LFS di RS. X Surakarta. Pasien dinilai dengan mengisi kuesioner JOABPEQ dan ODI, kemudian dilakukan evaluasi MRI sagittal lumbar untuk menentukan derajat Lee score, kemudian melakukan uji korelasi pada data yang diperoleh. Penelitian ini menunjukkan korelasi yang signifikan antara Skor Lee dengan JOABPEQ dan ODI. Tingkat LFS berdasarkan Lee Score memiliki korelasi yang signifikan dengan tingkat disabilitas menggunakan JOABPEQ dan ODI. JOABPEQ memiliki korelasi yang lebih signifikan dengan Skor Lee dibandingkan dengan ODI. Kata Kunci : Lumbar Foraminal Stenosis, Lee Score, JOABPEQ, ODI Lumbar Foraminal Stenosis (LFS) can significantly reduce the patient’s function and quality of life and Magnetic Resonance Imaging (MRI) is commonly used supporting tool to measure the degree of stenosis. Lee Score is commonly used to measure the degree of LFS on sagittal MRI. Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and Oswestry Disability Index (ODI) to assess disability and functional scores in LFS patients. This study was conducted to determine the correlation between the degree of LFS on sagittal MRI images with quality of life in patients with LFS.This study is an observational analytics study involving 25 patients with clinical symptoms of LFS in X Hospital Surakarta. Patients were assessed by filling JOABPEQ dan ODI questionnaires, then performed sagittal lumbar MRI evaluation to determine the degree of Lee Score, then performed correlation test on the data obtained.This study shows a significant correlation between Lee Score with JOABPEQ and ODI. The degree of LFS based on Lee Score has a significant correlation with the degree of disability using JOABPEQ and ODI. JOABPEQ has a more significant correlation to Lee Score compared with ODI. Keywords:Lumbar Foraminal Stenosis, Lee Score, JOABPEQ, ODI

scholarly journals De-noising of MRI Images in Wavelet Domain

2019 ◽  
Vol 8 (4) ◽  
pp. 1947-1949
Keyword(s):  
Signal To Noise Ratio ◽  
Histogram Equalization ◽  
The Body ◽  
Medical Procedure ◽  
Wavelet Domain ◽  
Radio Waves ◽  
Resonance Imaging ◽  
Adaptive Histogram Equalization ◽  
Magnetic Resonance Imaging Mri

Magnetic resonance imaging (MRI) is a diagnostic medical procedure that utilizes solid attractive fields and radio waves to deliver definite pictures of within the body. Extensive research has been completed into whether the attractive fields and radio waves utilized during MRI sweeps could represent a hazard to the human body. No proof has been found to propose there's a hazard, which means MRI outputs are one of the most secure restorative methodology accessible. MRI has several advantages which make it ideal in numerous situations, in particular, it can identify small changes of structures inside the body. The disadvantage is the noise that degrades the quality of the image. A threestep processing algorithm is proposed to reduce this noise. Here, first it includes soft thresholding in wavelet domain where the original image is divided into blocks that do not overlap. Then it includes restoration of the object boundaries and texture which are lost as a result of the first step and finally enhancing the image using CLAHE (Contrast Limiting Adaptive Histogram Equalization). It is then analyzed using the error parameters like peak signal to noise ratio and mean square error.

scholarly journals 592 A Large Lipoma: An Unusual Presentation of the Tongue

2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
A Shathur ◽  
A Rashid ◽  
V Patel ◽  
L Ffolkes ◽  
R Jayaram
Keyword(s):  
Unknown Origin ◽  
The Body ◽  
Tongue Movement ◽  
Resonance Imaging ◽  
Patient History ◽  
Lateral Border ◽  
Soft Tissue Swelling ◽  
Magnetic Resonance Imaging Mri ◽  
And Function

Abstract Background Lipomas are commonly identified tumours of the body however they are rarely found in the oral cavity. Rarer still is it to report a case of a lipoma in the tongue as they are more commonly located in the buccal mucosa. Objectives To diagnose and explore the pathogenesis of a soft-tissue swelling of unknown origin Method A thorough patient history and clinical examination was undertaken followed by magnetic resonance imaging (MRI) which revealed an alarming report at first glance. An incisional biopsy of the lesion was then carried out to aid in diagnosing the lesion. Results The swelling caused the patient no pain however the mere size of the lesion affected the patient’s tongue movement and function which therefore affected the patient’s quality of life. The imaging and the biopsy of the lesion led to a diagnosis of a large lipoma on the lateral border of the tongue. Conclusions To the authors’ best knowledge, we present a rare case of a patient whom we diagnosed with a large lipoma on the lateral border of the tongue. This case report discusses the stages of patient management from initial presenting complaint, up to the maintenance of the patient following the diagnosis of this lesion.

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