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1.
Diagnostics (Basel) ; 13(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38066782

RESUMO

(1) Background: Colorectal cancer is the third most common type of cancer with a high mortality rate and poor prognosis. The accurate prediction of key genetic mutations, such as the KRAS status, tumor staging, and extramural venous invasion (EMVI), is crucial for guiding personalized treatment decisions and improving patients' outcomes. MRI radiomics was assessed to predict the KRAS status and tumor staging in colorectal cancer patients across different imaging platforms to improve the personalized treatment decisions and outcomes. (2) Methods: Sixty colorectal cancer patients (35M/25F; avg. age 56.3 ± 12.9 years) were treated at an oncology unit. The MRI scans included T2-weighted (T2W) and diffusion-weighted imaging (DWI) or the apparent diffusion coefficient (ADC). The manual segmentation of colorectal cancer was conducted on the T2W and DWI/ADC images. The cohort was split into training and validation sets, and machine learning was used to build predictive models. (3) Results: The neural network (NN) model achieved 73% accuracy and an AUC of 0.71 during training for predicting the KRAS mutation status, while during testing, it achieved 62.5% accuracy and an AUC of 0.68. In the case of tumor grading, the support vector machine (SVM) model excelled with a training accuracy of 72.93% and an AUC of 0.7, and during testing, it reached an accuracy of 72% and an AUC of 0.69. (4) Conclusions: ML models using radiomics from ADC maps and T2-weighted images are effective for distinguishing KRAS genes, tumor grading, and EMVI in colorectal cancer. Standardized protocols are essential to improve MRI radiomics' reliability in clinical practice.

2.
Healthcare (Basel) ; 11(18)2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37761705

RESUMO

BACKGROUND: The lack of local guidelines and regulations for the administration of anesthesia in magnetic resonance imaging (MRI) units presents a potential risk to patient safety in Saudi Arabia. Hence, this study aimed to evaluate the extent to which hospitals in Saudi Arabia follow international guidelines and recommendations for the safe and effective administration of anesthesia in an MRI environment. METHODS: This study used a questionnaire that was distributed to 31 medical facilities in Saudi Arabia that provided anesthesia in MRI units. RESULTS: The findings of the study revealed that the mean compliance with the 17 guidelines across the 31 sites was 77%; 5 of the 31 sites (16.1%) had a compliance rate of less than 50% with the recommended guidelines. Only 19.4% of the institutes provided general safety education. Communication breakdowns between anesthesia providers and MRI teams were reported. CONCLUSIONS: To conclude, this survey highlights the status of anesthesia standards in Saudi Arabian MRI units and emphasizes areas that require better adherence to international guidelines. The results call for targeted interventions, including the formulation of specific national anesthesia guidelines for MRI settings. Communication breakdowns between anesthesia providers and MRI teams were reported at a rate of 83.9% during the administration of a gadolinium contrast agent. There were additional breakdowns, particularly for high-risk patients with implants, such as impaired respirators (74.2%), thus requiring further investigation due to potential safety incidents during MRI procedures. While considering the limitations of this study, such as potential biases and the low response rate, it provides a valuable foundation for refining protocols and promoting standardized practices in Saudi Arabian healthcare.

3.
Healthcare (Basel) ; 11(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36900726

RESUMO

PURPOSE: The American College of Radiology (ACR) requires MR personnel not to work alone due to the increased risk of safety issues such as projectiles, aggressive patients, and technologist fatigue. As a result, we intend to assess the current safety of lone-working MRI technologists in MRI departments in Saudi Arabia. MATERIALS AND METHODS: A cross-sectional study using a self-report questionnaire was conducted in 88 Saudi hospitals. RESULTS: A response rate of 64% (174/270) was obtained among the 270 MRI technologists which were identified. The study discovered that 86% of MRI technologists had prior experience working alone. In terms of MRI safety training, 63% of MRI technologists received such training. A question about lone MRI workers' awareness of the ACR's recommendations revealed that 38% were unaware of such recommendations. Furthermore, 22% were misinformed, believing that working alone in an MRI unit is optional or depends on the individual's desire to work alone. Working alone has the primary consequence of being statistically significantly associated with projectile/object-related accidents/mistakes (p = 0.03). CONCLUSION: Saudi Arabian MRI technologists have extensive experience working alone without supervision. Most MRI technologists are unaware of lone working regulations, which has raised concerns about accidents/mistakes. There is a need for MRI safety training and adequate practical experience to raise awareness of MRI safety regulations and policies related to lone working among departments and MRI workers.

4.
Int J Gen Med ; 15: 6289-6299, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35924179

RESUMO

Purpose: Magnetic resonance imaging (MRI) is an important diagnostic method in modern clinical medicine. Patients' knowledge about MRI is of utmost importance for optimizing the workflow, safety, and patient comfort and saving valuable time for the MRI department. This study investigates patient knowledge levels regarding MRI safety before an MRI examination. Patients and Methods: A cross-sectional survey was completed by 200 patients who required MRI. Recruitment occurred over eight weeks in governmental and private hospitals in Saudi Arabia; both hospitals and participants were selected randomly. The questionnaire was given to the patients prior to their MRI scans. Descriptive statistics and chi-square tests were performed to identify relationships between knowledge of MRI safety and selected demographic groupings (age, gender, education level, income level). It also evaluates their source of information and assesses the patient's previous experience regarding MRI scans. . Results: The study sample consisted of 200 patients from 230 surveys distributed in Saudi Arabia, and the response rate was ~ 87%. Depending on the P-values of the chi-square statistical test to find the relationship between socio-demographic factors and patient' knowledge level, the results showed a significant association (p-value=0.006) between age and gender and the level of knowledge relating to MRI safety issues. A similar significance (p-value=0.042) is observed between the knowledge level of patients and their educational level and annual income. In addition, a highly significant association (p-value<0.001) is found between education level or previous experience and whether people seek information about MRI safety. Conclusion: The study findings suggest that a complex combination of factors affects patient knowledge regarding MRI safety before an MRI examination. Hence, the hospital and radiological department must provide the patient with accurate information about MRI. .

5.
Acta Radiol Open ; 11(6): 20584601221105228, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35677731

RESUMO

Background: Magnetic Resonance Imaging (MRI) is considered a vital in depicting multiple sclerosis (MS) lesions. Current studies demonstrate that proton density (PD) weighted images (WI) are superior to T2 WI in detecting MS lesions (plaques) in the spinal cord. Purpose: To evaluate the diagnostic value of filtered fused PD/T2 weighted images in detecting cervical spinal cord MS lesions. Material and Methods: In this retrospective study, we selected a sample size of 50 MS patients. Using contrast limited adaptive histogram equalization (CLAHE), a digital image processing filter was used on the (PD/T2) fused images. The produced images were inspected and compared to the original PD images by two experienced neuroradiologists using interobserver and intraobserver. An ROI analysis was also performed on the processed and original PD images. Results: The repeatability measurement of the match between the two examinations was highly consistent for both neuroradiologists. The repeatability for both neuroradiologists was 96.05%, and the error measurement was 3.95%. The reproducibility measurement of the neuroradiologist's evaluation shows that the processed images could help to identify lesions better [excellent (84.87%)] than PD images [good (61.19%)]. ROIs analysis was performed on 113 MS lesions and normal areas in different images within the sample size. It revealed an enhanced ratio of 2.2 between MS lesions and normal spinal cord tissue in processed fused images compared to 1.34 in PD images. Conclusion: The processed images of the fused images (PD/T2) have superior diagnostic sensitivity for MS lesions in the cervical spine than PD images alone.

6.
Appl Radiat Isot ; 178: 109965, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688024

RESUMO

The positron emitters (18F-Sodium Fluoride (NaF)) and X-rays used in Positron emission tomography (PET) combined with computed tomography (PET/CT) imaging have a high radiation dose, which results in a high patient dose. The present research intends to determine the radiation dose and risks associated with PET/CT- 18F-Sodium fluoride examinations in patients. The 18F-NaF PET/CT was used to investigate the doses of 86 patients. Patient exposure parameters and ImPACT software were used to calculate mean effective doses. The administered activity of 185 MBq (5.0 mCi) per procedure has a mean and range based on the patient's BMI (BMI). The range of patient effective doses per procedure was found to be 4-10 mSv, with a radiation risk of 1 × 10-5 per procedure. Patient doses are determined by the patient's size, scanner type, imaging protocol, and reconstruction method. For further dose reduction, proper justification and radiation dose optimization is required.


Assuntos
Radioisótopos de Flúor/administração & dosagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Doses de Radiação , Fluoreto de Sódio/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Appl Radiat Isot ; 168: 109520, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33307438

RESUMO

The various technological advancements in computed tomography (CT) have resulted in remarkable growth in the use of CT imaging in clinical practice, not the least of which has been its establishment as the most valuable imaging examination for the assessment of cardiovascular system disorders. The objective of this study was to assess the effective radiation dose and radiation risk for patients during cardiac CT procedures, based on studies from four different hospitals equipped with 128 slice CT equipment. A total of eighty-three patients were investigated in this study with different clinical indications. Effective doses were also calculated using software based on Monte Carlo simulation. The mean patient age (years), weight (kg), and body mass index (BMI (kg/m2)) were 49 ± 11, 82 ± 12, and 31 ± 6, respectively. The results of the study revealed that the tube voltage (kVp) and tube current-exposure time product (mAs) ranged between 100 to 140 and 50 to 840 respectively. The overall average patient dose values for the volume CT dose index [(CTDIvol), in mGy)] and dose length product (DLP) (in mGy·cm) were 34.8 ± 15 (3.7-117.0) and 383.8 ± 354 (46.0-3277.0) respectively. The average effective dose (mSv) was 15.2 ± 8 (1.2-61.8). The radiation dose values showed wide variation between different hospitals and even within the same hospital. The results indicate the need to optimize radiation dose and to establish diagnostic reference levels (DRLs) for patients undergoing coronary computed tomography angiography (CCTA), also to harmonize the imaging protocols to ensure reduced radiation risk.


Assuntos
Angiografia Coronária/métodos , Coração/efeitos da radiação , Tomografia Computadorizada por Raios X/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Adulto Jovem
8.
PLoS One ; 10(6): e0130133, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26110770

RESUMO

Magnetic Resonance Imaging (MRI) of the rodent brain at ultra-high magnetic fields (> 9.4 Tesla) offers a higher signal-to-noise ratio that can be exploited to reduce image acquisition time or provide higher spatial resolution. However, significant challenges are presented due to a combination of longer T1 and shorter T2/T2* relaxation times and increased sensitivity to magnetic susceptibility resulting in severe local-field inhomogeneity artefacts from air pockets and bone/brain interfaces. The Stejskal-Tanner spin echo diffusion-weighted imaging (DWI) sequence is often used in high-field rodent brain MRI due to its immunity to these artefacts. To accurately determine diffusion-tensor or fibre-orientation distribution, high angular resolution diffusion imaging (HARDI) with strong diffusion weighting (b >3000 s/mm2) and at least 30 diffusion-encoding directions are required. However, this results in long image acquisition times unsuitable for live animal imaging. In this study, we describe the optimization of HARDI acquisition parameters at 16.4T using a Stejskal-Tanner sequence with echo-planar imaging (EPI) readout. EPI segmentation and partial Fourier encoding acceleration were applied to reduce the echo time (TE), thereby minimizing signal decay and distortion artefacts while maintaining a reasonably short acquisition time. The final HARDI acquisition protocol was achieved with the following parameters: 4 shot EPI, b = 3000 s/mm2, 64 diffusion-encoding directions, 125×150 µm2 in-plane resolution, 0.6 mm slice thickness, and 2h acquisition time. This protocol was used to image a cohort of adult C57BL/6 male mice, whereby the quality of the acquired data was assessed and diffusion tensor imaging (DTI) derived parameters were measured. High-quality images with high spatial and angular resolution, low distortion and low variability in DTI-derived parameters were obtained, indicating that EPI-DWI is feasible at 16.4T to study animal models of white matter (WM) diseases.


Assuntos
Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Animais , Artefatos , Imagem de Tensor de Difusão/métodos , Imagem Ecoplanar/métodos , Análise de Fourier , Leucoencefalopatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Software
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