Medical Imaging Technology تكنولوجيا التصوير الطبي

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An Advanced Approach to Reconstruct CT Images from limited-angle projections, reducing radiation dose and tube load.
(Al-Quds University, 2023-12-12) Doaa Housni Ali Bani Odeh; دعاء حسني علي بني عودة
Concerns regarding ionizing radiation doses to individuals and patients have arisen as a result of the remarkable advancements in computed tomography (CT) technology and applications over the last ten years, so Computed tomography (CT) scanners and CT exams have increased continuously. Researchers aim to minimize ionizing radiation dose via introducing new CT protocols and providing diagnostic CT images with lower radiation doses to patient. Nevertheless, these investigations have challenges: reducing the radiation dose results in decreased image quality, which might occasionally be non-diagnostic. In This study, the researcher aims to investigate the possibility of forming a CT brain image from a limited number of projections at a projection angle of less than 180 degrees While maintaining image quality based on the ALARA principle and decreasing radiation dose. then determine if the images match the quality criteria of Brain CT. This effort spanned from January 2023 to September 2023. The process of reconstructing CT scan images from limited angle projections is critical and requires strict adherence to the ALARA principle. This principle is designed to minimize radiation exposure while maintaining image quality. Our study utilized filter back-projection (FBP) and algebraic iterative reconstruction (IR) algorithms to reconstruct brain CT images from 500 projection lines with a 100 x 100 and 200 x 200 matrix size. In addition to researching the effect of the reconstruction angle on image quality, two degrees were taken at an angle of 90 and 45 degrees. The images were evaluated for image quality criteria by 10 expert medical imaging technicians and 2 radiologists and specific evaluations were given. Then, a simple descriptive statistical analysis was conducted, including calculating percentages for expert medical imaging technicians and radiologists evaluations and p-values. By combining the results of a MATLAB 2021 functions with the insights of a radiologist, we can produce high-quality images that decrease radiation dose and tube load. Our findings reveal that the algebraic method is superior to the filter back-projection in preserving image quality when utilizing limited-angle projections. In addition to the Statistical t-test (P<.001), which confirms the existence of statistical differences between the two algorithms. With a percentage of 41%, or a moderate scale, the IR algorithm matches quality requirements better. Conversely, the FBP exhibits a proportion of < 25%, signifying a weak scale. Based on the percentages of evaluation, we can confirm that the size of the Matrix 200 x 200 is superior to the size of the Matrix 100 x 100, as it formed a percentage of 36.25%, which is equivalent to a moderate scale. In addition, the reconstruction angle of 90 provides better quality and its percentage was 41.75%, equivalent to a moderate scale. So the IR algorithm at 90 degree with 500 projection only provides images that match the quality criteria for brain CT. while FBP fails to provide any meaningful insights when working with angles of 45 and 90 degrees.
Analysis of Tumor Markers Effect after Radiation Exposure among Palestinian Radiation Workers
(Al-Quds University, 2020-06-12) Areej Najeeb Ali Dahdol; اريج نجيب علي دحدو ل
Objective: The aim of this work was to investigate the effect of low radiation doses on tumor markers tests. And to follow up the policy that carrying out the tests for Radiation Workers. Also, demonstrate the effect of independent variables such the cumulative dose, Hospital location, and type of work on tumor markers. Method: the researcher reviews a retrospectively collected database of tumor marker tests in four governmental hospitals +between 2013- 2019, to following the patterns of tumor marker over the years. The cumulative doses records were taken from energy department in ministry of health. Additionally to distribute a questionnaire to correlate independent variables with tumor markers records and also to demonstrate the policy following of carrying out these tests among RWs. 78 radiation workers participated. Results: after several years of following tumor markers, all tumor markers tend to increase in a normal range, especially the CEA; approximately 57% of radiation workers have an increase in CEA. The smoking workers have a statistically significant change in CEA; also the study not shown any relationship between the radiation doses and tumor markers. While a measure of the knowledge level of policy show 73% of worker answered that no one is responsible for following tests results. Further, 91% of workers admit no action was taken in the event of an abnormal result found. Conclusion: Until now all tumor markers results was in a normal range, even if they tend to a little increase from year to year, but that still prove nothing without repeat this study and comparing this group of worker with another different type of workers, to understand if this increase that have noticed here in this study come from radiation or not. Otherwise highlight the role of policy officer who’s responsible for monitoring the carrying out these tests and follow up what happen on radiation workers tests results.
Assessment of Knowledge and Practices of Intensive Care Unit Staff of Radiation Protection during Portable Radiography in the City of Bethlehem and East Jerusalem, Palestine
(Al-Quds University, 2023-05-13) Elias Issa Elias Juha; الياس عيسى الياس جحا
The application of ionizing radiation in portable radiography is a commonly employed technique within hospital settings, particularly when patients are deemed medically unfit to undergo transportation to the imaging department. Nonetheless, this circumstance might result in personnel being exposed to radiation. This study evaluated the physicians’ and nurses’ awareness level and practices of radiation protection principles and risks of portable radiography in the ICUs, CCUs, and NICUs at nine Bethlehem and East Jerusalem hospitals. For data collection, the researcher designed a prospective multiple-choice questionnaire study consisting of six parts; the first part contains six questions about socio-demographic factors and related work information; the second part deals with radiation protection knowledge and awareness of the intensive care staff; the third part deals with the practices and behavior during portable radiography; the fourth part assesses how often the intensive care staff uses radiation protection equipment; the fifth part studies the staff’s needs for further training and courses regarding radiation protection, and the last part deals with how often the intensive care staff rates their knowledge of radiation protection. The data were analyzed using the SPSS, version 21.0 software, T-test, Tukey test, and ANOVA test. Moreover, the means, standard deviations, and percentages were founded. The results show statistically significant differences between the level of knowledge (P=0.000) and the need for further training and courses regarding radiation protection (P=0.040) according to the years of practice variable. Also, statistically significant differences between the level of knowledge (P=0.000) and the need for further training and courses regarding radiation protection (P=0.045) according to the age variable. Furthermore, statistically significant differences between the level of knowledge (P=0.000) and their behavior and practice (P=0.018) according to the academic education variable, and statistically significant differences between the need for further training and courses (P=0.016) and the use of radiation protection equipment (P=0.029) according to the hospital sector variable. Moreover, the results indicate that there are no differences between the level of knowledge, the need for further training, the use of radiation protection equipment, and practices according to the gender and occupation variables, no differences between the use of radiation protection equipment and practices according to the age and years of practice variables, no differences between the need for further training and courses and the use of radiation protection equipment according to the academic education variable, and no differences between the level of knowledge and practices according to the hospital sector variable. Accordingly, our sample consists of 142 particpents, the overall knowledge and awareness level regarding radiation protection and risks was found to be 56% and rated as fair. Moreover, 56.3% of the participants were found to leave the intensive care department during portable radiography, and 48.6%, 62.7%, 68.3%, and 73.9% stated that they never use lead aprons, thyroid shields, lead gloves, and eyeglasses, respectively. While, 72.5% stated they never attended training or courses regarding radiation protection and 79.6% stated that continuous education officer does not provide them courses or refreshment lectures regarding radiation protection. Thus, their educational level and awareness need to be increased. Implementing courses, presentations, refreshment lectures, and periodic training for these personnel could effectively achieve this goal. Further research using a larger sample is recommended.
Assessment of radiation doses for cardiac and left anterior descending coronary artery in patients undergoing Left breast radiation therapy in Palestine
(Al-Quds University, 2020-08-15) Bayan Saleh Ali Suleiman; بيان صالح علي سليمان
Purpose: To evaluate radiation doses in cardiac radiotherapy planning in left breast cancer patients using 3D conformal radiotherapy planning technique based on computed tomography (CT) dose planning. Methods: Data was retrospectively collected from archived Computed Tomography (CT) images, whole heart and left anterior descending coronary artery (LAD) radiation doses at Augusta Victoria Hospital (AVH) between 2017-2019. Data composed of 176 breast cancer radiotherapy cases; 70 chest wall irradiated mastectomies patients, and 106 breast irradiated lumpectomies patients. Individual dose volume histograms for the whole heart and for LAD were obtained, in addition to the calculated mean, median and maximum volume percentage (V10%, V25%, V30%) of these structures for the study sample which represents the percentage of heart volume receiving (x) Gy or higher, then compared to the Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) guidelines and previous studies for dose assessment of heart and LAD. Represents the percentage of an organ’s volume receiving (x) Gy or higher Results: Results showed the whole mean heart dose (MHD) and the mean dose of LAD were 2.2 Gy and 13.94 Gy, respectively. In which, 4.5% of patients received MHD ≥ 4Gy, all subjects received V25% less than 10cm expect one V25% ≥ 10. 11 % of patients received LAD maximum dose ≥ 45 Gy. In spite of the dose variations found in both MHD and LAD in this study, and the dose differences noticed when compared to studies that used other radiotherapeutic techniques such as Deep Inspiration Breath Hold technique (DIPTH), MHD and LAD dose assessments were equivalent to those of the compared previous studies and Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) guidelines. Conclusions: Dose assessments of adjuvant CT-based radiotherapy of subjects with left breast cancer demonstrated similar MHD but higher LAD doses when compared to previous studies and QUANTEC guidelines used to predict cardiac toxicities in most patients in the study sample. Since there is no worldwide standardized protocol or heart dose constrains in left breast radiotherapy, this study suggests maintaining the lowest received dose and volume of the heart or organ at risk included in the treatment plan, as well as using advanced techniques.as DIPH to reduce the latent effects on radiotherapy patients, especially the heart complications that could occur.
Awareness, Attitude and practice among Palestinian women regarding breast cancer screening (breast self-examination and mammography)
(Al-Quds University, 2024-01-14) Sabreen Ali Mohammed Thawabteh; صابرين علي محمد ثوابته
Breast cancer, being the most prevalent cancer among women worldwide, leads to about 400,000 deaths yearly. All women should have a basic understanding of breast self-examination (BSE). This study aims at determining Palestinian women’s knowledge, behavior and beliefs about BC and BSE. Data were obtained using a structured questionnaire that was distributed 200 female women’s Palestinian. The questionnaire evaluated the students’ knowledge, behavior, and attitudes about BC and BSE. The study revealed that 70% of the participants had an awareness of BC and 30% were unaware of the term BSE. only 30% had had a mammography screening, compared to 70%. The study participants' participation rates in mammography screening and BSE. According to the results, 63% of participants had never practiced BSE, compared to 37% who had. Furthermore, only 30% had had a mammography screening, compared to 70% who had not. These results highlight the necessity of raising public awareness and promoting BSE and mammography screening in order to enhance early identification and preventative measures for BC. Further efforts need to be done to expand women’s knowledge about BC, early detection and treatment.
Characterization of two variants in OSTM1 gene inosteopetrosis-affected Palestinian families.
(Al-Quds University, 2025-01-15) Maram Ali Shawkat Eid; مرام علي عيد
Background: Osteopetrosis is a rare genetic disorder characterized by increased bone density and brittle bones. Most cases result from mutations affecting lysosome-related organelle genes. One of the genes associated with osteopetrosis is the OSTM1 gene. Mutations in OSTM1 gene are linked to severe forms of the disease. Whole Exome Sequencing (WES) test was conducted on a group of affected Palestinian families, revealing two new variants c.365T>A (p.Val122Asp) and c.108C>T (p.Gly36Gly) in the OSTM1 gene. To our knowledge, these two variants have not been previously reported as pathogenic. Therefore, the study aims to determine their contribution to osteopetrosis. Methods: In order to evaluate the pathogenicity of these two genetic variants, whole blood samples were collected from each family member of the inflicted families. DNA and RNA were extracted from each sample. Variant segregation was performed following Sanger sequencing on the obtained samples from the affected volunteers and their extended families’ members. For the c.108 C>T (p.Gly36Gly) variant, which is hypothesized to create a donor splicing site, analysis was undertaken to look for splicing events that could result from the indicated variant. Primers flanking exons one and two were used to determine whether this variant results in abnormal splice variants of the OSTM1 gene. Results: Segregation of the two variants was assessed by examining their inheritance in 36 participants. The results revealed that unaffected individuals possess both variants either in a heterozygous or wild-type genotype, while affected individuals are homozygous for both variants, indicating a recessive inheritance pattern. RNA analysis of the c.108 C>T (p.Gly36Gly) variant in the OSTM1 gene was also performed. The findings demonstrated that this variant does not affect splicing, contrary to claims made in a 2013 case report by Mahmoud et al., suggesting that the variant might create a donor splice site. This also goes against the predictions made by splicing prediction tools, indicating that the c.108 C>T (p.Gly36Gly) variant could potentially function as a splice site. Conclusion: This study provided an opportunity to uncover the genetic variant responsible for the disease in the included families. Our results indicate that the variant c.365T>A (p.Val122Asp) segregates well between affected and unaffected family members, however, c.108C>T (p.Gly36Gly) variant does not affect splicing and thus seems to be a benign or neutral variant. This knowledge can help identify those at risk and provide preventative interventions, improving patient counselling and raising awareness about the importance of premarital screening for the pathogenic variant of the OSTM1 gene.
A comparative study of SAR Distribution in patients undergoing MRI examinations at different field strengths and manufacturers
(Al-Quds University, 2024-08-20) Mohammad Jamil Mahmoud Mdallal; محمد جميل محمود مدلل
This study aims to assess and compare Specific Absorption Rate (SAR) levels, in patients undergoing MRI scans at 1.5 Tesla (1.5T) and 3 Tesla (3T) using Philips MRI systems. Additionally, it includes a comparison between 1.5 Tesla MRI systems from two industry manufacturers, Philips and Siemens. A cross-sectional prospective descriptive design was employed, involving 180 patients who underwent MRI scans at specified field strengths and manufacturer systems. The study was conducted at Al-Rahma Policlinic, Nablus, and Ibn Rushd Radiology Center, Hebron, West Bank, Palestine, from January to May 2024. SAR values were collected from MRI scan records and analyzed using statistical methods, including Mann-Whitney U tests and multiple regression analysis. The results demonstrated that Philips 3T systems exhibit significantly higher SAR values compared to Philips 1.5T systems, confirming that higher magnetic field strengths result in increased RF energy deposition. Additionally, Siemens 1.5T systems showed significantly higher SAR values than Philips 1.5T systems. differences in pulse sequence parameters, such as repetition time (TR), echo time (TE), and the number of slices, significantly affected SAR values, with longer TR and a higher number of slices associated with higher SAR. Lumbar MRI sequences generally exhibited higher SAR values compared to brain sequences. The study underscores the need for careful monitoring and optimization of MRI protocols to minimize SAR values, especially for high-field strength systems and different manufacturers' equipment. Continuous monitoring of SAR values and adherence to regulatory guidelines are essential to ensure patient safety during MRI scans.
A Comparative Study of Six Software Tools Used for Estimating Fetal Radiation Dose from CT Examinations
(Al-Quds University, 2024-11-04) Huda Husni Mahmoud Nasser; هدى حسني محمود ناصر
The assessment of fetal radiation dose during computed tomography (CT) examinations is crucial for ensuring the safety of the pregnant women and their fetuses. This study aimed to perform a comparative analysis of six MC-based software tools (VirtualDose CT, FetalDose.org, CODE, Waza-ari, ImPACT, and CT-Expo) for fetal dose estimation in various CT examinations, assessing their reliability and performance. The analysis involved estimating fetal radiation doses for pregnant women in our sample set using these tools. The six software tools were used to estimate fetal radiation doses for twenty-six pregnant participants undergoing twenty-seven different CT examinations, including head, cervical spine, chest, abdomen-pelvis, lumbar spine, and ankle scans. Single measures and average measures Intraclass Correlation Coefficient (ICC) values at 95% Confidence Interval (CI) were calculated, to assess the reliability of the six software tools together, and the pairs of software tools separately as well. Bland-Altman plots were also utilized to assess the agreement between some pairs of software tools. A comparative analysis for the six software tools’ performance in estimating fetal dose from CT examinations was also conducted. Total performance score was calculated for each tool based on the established criteria in this study, which are considered critical in performing dose estimates to fetus, including availability of pregnant phantoms, required inputs, availability of CT procedures, availability of CT scanner models, details of resulting fetal and maternal doses, number of available phantoms, cost, ease of use, and compatibility with mobile systems. The resulting fetal dose estimates were all within the ICRP-recommended threshold for deterministic effects, specifically below 100 milligray (mGy). Average measures ICC value for the six software tools was found to be 0.96 (95% CI: 0.91 – 0.98), indicating excellent reliability, whereas single measures ICC value for the six software tools was found to be 0.80 (95% CI: 0.63 – 0.90), indicating moderate to excellent reliability of an individual software tool with the others. VirtualDose CT and FetalDose.org showed the highest single measures ICC value across all pairs of software tools at 0.98 (95% CI: 0.96 – 0.99), indicating excellent reliability of both tools. Whereas CODE software showed the lowest single measures ICC values with all other software tools, indicating a low reliability of this software tool. Bland-Altman plot showed a mean difference of 0.79 for VirtualDose CT and FetalDose.org software tools, with limits of agreement ranged from – 2.45 to 4.03, indicating a good agreement between both tools, and confirming their reliability as well. For the comparative analysis of the software tools’ performance in calculating fetal dose from CT examinations, VirtualDose CT was identified as the best performer according to the predefined criteria evaluated in this study with a total performance score of 485.25. Ultimately, VirtualDose CT, with its superior performance and high reliability, was recommended as a standout tool for fetal dose estimates from CT examinations.
Criteria for dental implant selection in Palestine
(Al-Quds University, 2024-06-10) Bara'a abd alhakeem jobran rojoub; براءة عبد الحكيم جبران رجوب
Dental implants are alloplastic materials that are placed in order to assist repair or replace damaged orofacial components. The outcome is dependent on how well the implant's substance integrates with the surrounding tissue. However, this integration is influenced by several factors, such as implant material, bone quantity and quality, and implant loading status. Accurately detecting anatomical features in relation to implant size increases the success rate of implant surgery and reduces the risk of surgical damage. This can only be accomplished by a comprehensive and suitable radiological examination. In order to help the dentist, determine the best kind of implant for the patient, the study focuses at the characteristics of the implant and the medical imaging modalities Cone Beam Computed Tomography (CBCT) and panoramic that the dentist performs. A cross-sectional descriptive study about the functions of medical imaging in dental implants and the factors that influence selecting the type of implant among Palestine's dentists who perform dental implant. An online survey including inquiries about preferred dental implants, the status of patient’s economy, and other important factors that influenced their choice of implant type. The statistical analysis conducted using IBM SPSS v27 to investigate the relationships and differences between various variables, Cronbach's alpha, chi-square test, Spearman's rank correlation, Kruskal Wallis and Mann-Whitney U test were used to examine relationship between the study’s variables. Throughout the analysis, we consider statistically significant of a P-value of less than 0.05, indicating that observed effects were unlikely to be due to chance. 94.6% of participants stated that CBCT is their primary medical imaging modality. Additionally, the study's findings indicate that the following factors influenced the dentist's decision regarding the type of implant: (a) the time required for the procedure, which was 69.8% P-Value ˂0.001; (b) the patient's age, which was 60.4% P-Value ˂0.001; (c) the implant's cost, which was 62.8% P-Value ˂0.001; and (d) the patient's required number of implants, which was 59.7% P-Value ˖0.001. Surgical implants were selected primarily in comparison to basal and compressive implants based on characteristics such as implant stability, success and continuity, surrounding bone growth, and the expected medical benefit overall. The majority of Palestinian dentists use CBCT to identify the type of implant. Additionally, the outcomes demonstrated that while basal implants produce equivalent results more quickly, dentists did not initially favor them. When choosing an implant type, dentists considered the patient's age, the duration of the surgery, and the implant's cost into account.
Cross-Modality Transfer Learning for Reliable Lung Cancer Nodule Classification in Low-Dose CT
(Al-Quds University, 2026-01-08) Sara Rasheed Saleh Asfour; سارة عصفور
Lung cancer is the leading cause of cancer-related mortality worldwide and remains a major health burden in Palestine. According to the Palestine Annual Health Report 2024, lung and bronchus cancers accounted for 316 newly diagnosed cases (10.5 per 100,000 population) and 266 deaths, with 85% occurring among males. These epidemiological patterns highlight the urgent need for locally validated AI solutions that support early lung cancer detection and robust clinical decision-making, particularly in resource-limited healthcare settings where radiological expertise and structured screening programs remain limited. This study proposes a dose-aware hybrid deep-learning–machine-learning framework for multi-class Lung-RADS classification using heterogeneous chest CT datasets collected from multiple Palestinian institutions. The framework integrates optimized contrast enhancement, deep feature extraction using VGG16, and five classical machine-learning classifiers (LR, SVM, RF, GB, and DT). Contrast enhancement was systematically evaluated using two subsets of 120 malignant cases, one LDCT and one SDCT which is demonstrating that the hybrid CLAHE-USM provided the most balanced improvements (EME = 20.648, PSNR = 19.711, SSIM = 0.912). Dose-optimized parameters, including a clip limit of 3 for LDCT and 4 for SDCT, confirmed the importance of dose-specific preprocessing in stabilizing image quality. The classification results obtained across the LDCT, combined, external validation, and clinical validation datasets demonstrate that the proposed VGG16-machine learning framework provides robust and consistent performance for Lung-RADS-based nodule risk stratification. On the LDCT dataset, all classifiers achieved clinically meaningful performance, although variability was observed across Lung-RADS categories. GB and decision tree classifiers demonstrated powerful performance in LR2 and higher-risk categories, achieving accuracies above 0.85. A clear performance improvement was observed with increasing risk of malignancy. For LR4A and LR4B, most classifiers achieved higher accuracy than in lower-risk categories, reflecting the greater structural distinctiveness of high-risk nodules. The most important performance gains were observed on the combined LDCT-SDCT dataset, particularly for LR3 and LR4A-LR4B. In this setting, SVM and RF achieved near-ceiling performance, with accuracies exceeding 0.97 and AUC values approaching unity. External validation on an independent test set from Al-Makassed Hospital further confirmed the robustness of the proposed framework. For LR2, all major classifiers achieved accuracies above 0.84, whereas for LR4B, all major classifiers achieved accuracies above 0.86. The most stringent assessment of diagnostic performance was provided by Clinical validation on biopsy-confirmed LR4B cases from Augusta Victoria Hospital. SVM achieved the highest accuracy and AUC, followed closely by LR. Overall, this framework demonstrates strong potential as a practical decision-support tool for improving Lung-RADS-based risk stratification and supporting early lung cancer detection in resource-constrained healthcare settings
Deep Clustering Approaches for Carotid Artery Calcification Detection in Panoramic Radiographs for Enhancing Cardiovascular Risk Prediction
(Al-Quds University, 2026-01-08) Nadeen Khaled Ibrahim Erekat; نادين خالد إبراهيم عريقات
Cardiovascular disease remains a leading cause of death worldwide, making early identification of vascular risk markers essential for prevention. Carotid artery calcifications can occasionally be visualized on panoramic dental radiographs, offering an opportunistic indicator of atherosclerotic burden during routine dental care. Yet, manual identification is challenged by inter-reader variability and the presence of anatomical mimics, and many published AI solutions rely on supervised learning that requires large, densely labeled datasets. This thesis investigates an alternative pathway by developing an unsupervised deep clustering framework for carotid region analysis on panoramic radiographs, and by integrating questionnaire-based risk factor modeling to support broader cardiovascular risk stratification. This single-center retrospective cross-sectional observational study included 1,107 panoramic radiographs acquired between February 2025 and August 2025 during routine dental examinations at Abraj Dental Clinics affiliated with Al-Quds University, in collaboration with the Faculty of Dentistry. In addition, a cross-sectional questionnaire sub-study was prospectively administered to a subset of participants (n = 438) to capture cardiovascular risk profiles and support complementary non-imaging analyses. The imaging cohort comprised 48% males and 52% females, with an age range of 18–85 years and a mean age of approximately 40 years. Preprocessing consisted of contrast enhancement using Contrast Limited Adaptive Histogram Equalization (CLAHE) followed by extraction of bilateral carotid regions of interest (ROIs), resized to 128×128 pixels. To represent each ROI, a dual feature strategy was adopted. Interpretable handcrafted radiographic features were computed to quantify intensity distributions, texture patterns, and edge- and morphology-related cues potentially associated with calcification. In parallel, deep representations were learned using a convolutional autoencoder pretrained for 300 epochs with mean squared error loss and a low-dimensional latent space, producing compact feature vectors suitable for downstream clustering. Four clustering methods were evaluated: K-Means, hierarchical clustering, Gaussian Mixture Models, and Deep Embedded Clustering (DEC). Clustering quality was assessed using internal validation metrics that do not require ground truth labels, including the Silhouette score, Davies–Bouldin index, and Calinski–Harabasz index. To connect unsupervised clustering outcomes to clinical relevance, the thesis adopted a patient-level validation strategy, where each patient contributed left and right ROI assignments. A high-risk validation subset of 21 patients was defined using confirmed cardiovascular disease history or documented carotid calcifications in clinical records. Patient-level accuracy was calculated based on the proportion of high-risk patients grouped into the dominant high-risk cluster. Model interpretability was further supported using GradCAM++ visualization to highlight salient ROI regions consistent with expected calcification-related patterns. DEC achieved the strongest clustering performance across the internal metrics, with a Silhouette score of 0.214, a Davies–Bouldin index of 1.752, and a Calinski–Harabasz index of 524, indicating improved within-cluster cohesion and between-cluster separation relative to baseline methods. Patient-level validation also favored DEC, which achieved 95.2% accuracy in aggregating high-risk patients into a dominant cluster with fewer anomalous cases compared with K-Means, hierarchical clustering, and GMM. To incorporate non-imaging determinants of cardiovascular risk, prospectively administered questionnaire data were analyzed for 438 participants (220 high risk, 218 low risk). Univariate association testing using chi-square statistics with Cramér’s V suggested notable associations with age, physical activity, sleep duration, sedentary time, dietary behaviors, selected health awareness indicators, and mental health measures such as relaxation difficulty and feelings of worthlessness. A Random Forest classifier trained on questionnaire features achieved high predictive performance (accuracy = 0.9318, ROC AUC = 0.9821, F1 = 0.9291), and feature importance analysis highlighted socioeconomic factors and psychological distress-related variables among influential predictors alongside age and lifestyle behaviors. In conclusion, this thesis demonstrates that unsupervised deep clustering of anatomically defined carotid ROIs on panoramic radiographs can yield coherent groupings aligned with clinically defined high-risk status, while offering an interpretable and label-efficient screening support pathway. Combining imaging-based signals with questionnaire-derived risk factors may further strengthen cardiovascular risk stratification and support targeted referral for confirmatory vascular assessment. Future work should incorporate gold-standard vascular confirmation, multi-site external validation, and longitudinal outcome linkage to establish clinical reliability and generalizability.
Detection and Quantification of Iron in Liver and Myocardium using MRI
(AL-Quds University, 2019-07-20) بسام عبد العزبز موسى ابو عرقوب; Bassam Abdelazeez Musa Abuarqoub; محمد حجوج; حسين المصري; ابراهيم حرباوي
Effect of magnetic field strength and sequence type on susceptibility artefacts: a comparative study utilizing low and high field strength magnetic resonance imaging scanners
(Al-Quds University, 2023-12-11) Alaa Mahmoud Ali Qalalweh; علاء محمود علي قلالوة
Many patients need to implant metal screws in several areas in their bodies as treatment procedures, and these metal implants cause an artefact around them in the magnetic resonance image, so the area around the metal implants can't be better evaluated, and this artefact increases whenever the magnetic field increased, for example, using the device with the magnetic field 1.5 T causes a greater susceptibility artefact than using a device with 0.4 T magnetic field. This type of artefact leads to repeat the MR image again using low field MR devices, this will increase the costs of diagnosis, increase the patient's exhaustion to obtain sufficient diagnosis, in addition to consuming more time to complete the diagnosis process. in this study, the measurements of the artefact around the titanium screws in low and high MR field was compared with the measurements of the screws in X-ray images. in addition to other sample was taken from calf spine that purchased from meat store that have been implanted with other 3 titanium screws, then underwent low and high field MR imaging in 3 repeats to get more accurate measurements, this artefact measurement around the screws in the calf spine was compared with the diameter of the same screws measurements on X-ray images. The result of this study was clarify that the use of low field MR device is better than the high field in case of presence of titanium screws in vertebral body, in addition to use titanium rather than other metallic materials that produce high susceptibility artefact in MR image, and this will be shown in the charts in this study. الكثير من المرضى يضطرون الى زرع براغي معدنية في عدة مناطق في اجسامهم كإجراءات علاجية، وهذه الزرعات المعدنية تسبب حولها تشويشا في صورة الرنين المغناطيسي، فتصبح المنطقة التي تحيط بالزرعات المعدنية غير قابلة للتشخيص، ويزيد هذا الخلل كلما ارتفع المجال المغناطيسي المستخدم، فمثلا استخدام الجهاز ذو قوة المجال المغناطيسي 1.5 تسلا يتسبب في خلل أكبر من استخدام جهاز بقوة 0.4 تسلا، هذا الخلل الناتج في الصورة يتسبب أحيانا بإعادة تصوير المريض على الجهاز منخفض المجال، ويزيد من تكاليف التشخيص، بالإضافة الى انه يزيد من معاناة المريض للحصول على تشخيص كاف، بالإضافة الى استهلاك المزيد من الوقت لإكمال عملية التشخيص. في هذه الدراسة يتم قياس الخلل الذي تسببه براغي التيتانيوم حولها عند التصوير باستخدام جهاز الرنين المغناطيسي منخفض المجال والجهاز عالي المجال، هذه القياسات تؤخذ لنفس البراغي بعد تصويرها في كلا المجالين، ثم يتم قياسها بالمليميتر، ومقارنتها مع القياسات لنفس البراغي على صور الاشعة السينية. بالإضافة الى غرس 3 براغي في عمود فقري لعجل تم شرائه من متاجر اللحوم، هذه البراغي جميعا تم تصويرها باستخدام المجالين أيضا، وتم إعادة تصوير هذه البراغي 3 مرات لزيادة دقة النتائج، وتم عمل القياسات لجميع هذه البراغي ومقارنة نتائجها بعضها مع بعض، ومقارنتها مع القياسات التي كتبت على البراغي بواسطة الشركة المصنعة. تبين في هذه الدراسة ان الخلل الناتج في صور الرنين المغناطيسي باستخدام الجهاز ذو المجال المرتفع أكبر بكثير من الخلل الناتج من استخدام الجهاز ذو المجال المنخفض، بالإضافة الى ان استخدام مواد مثل التيتانيوم التي تعتبر اقل تأثيرا في قابلية التمغنط يقلل من التشوه الموجود في صورة الرنين، وتبين المنحنيات في فصل نتائج الدراسة هذه الفروقات بشكل مفصل.
Effective patient Preparation durin Prostate Radiotherapy Evaluations of Bladder and Rectum Doses
(Al-Quds University, 2020-08-22) Qusai Mohammad Mustafa Tamim Tamimi; قصي محمد مصطفى تميم تميمي
Prostate cancer is a form of cancer that affects the prostate gland, it is considered as the second most mortality rate cancer among men. In low and intermediate risk prostate cancer patients,radiotherapy is the choice of treatment. With the advent of the radiation therapy it is now possible to treat the cancerous tissue accurately by localizing the tumor and then providing the exact dosing without harming the surrounding normal tissues. Image-guided radiation therapy or IGRT can evaluate the dose of radiation therapy to the target and Organs at Risks OARs effectively. The dose-volume histograms obtained from IGRT can help in assessing the effective dose of radiation given to the prostate, rectum, and bladder. This study was undertaken to assess the effect of bladder and rectum preparation protocol in dosevolume histograms (DVHs) in prostate cancer patients. The dosimetric changes resulted from the change in bladder and rectum volume with the bladder preparation and rectum clearance protocol were also evaluated in this study. In this retrospective study total 15 patients were included and 396 Cone Beam Computed Tomography CBCT scanning data was evaluated to obtain information. The patients were subjected to a bladder and rectum preparation protocol and insuring that they followed the protocol strictly. After the irradiation process DVH was constructed. The maximum, minimum and average dose to Urinary Bladder and Rectum were checked and compared to the DVH at the original plan which was calculated on the CT simulation images for each patient. Statistical significance was set at a P value < 0.05. Analyses were performed using R software and IBM SPSS version 23 for Windows. The result indicated that there is a significant difference between the planned bladder volume and also the average volume. The bladder filling protocol used by this study was able to reach a mean bladder volume of 314 mL. During the treatment time, this value got reduced and a mean bladder volume of 207 mL was achieved at the time of the radiotherapy. Also a statistically significant differences was observed regarding the bladder and rectum doses between planning and daily treatment sessions. Statistically significant differences in Rectum volume in both planned volume and average volume were reported. These differences are in both real values (P-value=0.024) and proportions to planned values (P-value=0.007). The change in mean dose to the bladder would increase while the volume of the bladder shrinks (P-value=0.00). The present study reported that rectum and bladder volume has a significant effect on the dosimetric parameters. The main contributing factor that can help in achieving the optimal plan is the bladder volume. Bigger bladder volume in the planning phase results in higher differences in volume and doses in the time of the treatment. .
Efficacy of automated breast ultrasound as a screening tool for detecting breast lesions in comparison with mammography and breast biopsy
(Al-Quds Univeersity, 2024-12-14) Ahlam Mohammad Asad Mubarak; أحلام محمد مبارك
Automated breast ultrasound (ABUS) has been developed as an advanced imaging technology designed to overcome the limitations of conventional breast screening modalities, particularly the reduced sensitivity of mammography in dense breast tissue and the operator dependency of handheld ultrasound (HHUS). This study aimed to evaluate the efficacy of ABUS as a screening tool for detecting breast lesions in comparison with mammography and breast biopsy. A descriptive, retrospective cross-sectional study was conducted involving 133 women who underwent both mammography and ABUS at Yazan Radiology Center in Bethlehem between January and December 2023. The mean age of participants was 51.71 years. Breast density distribution showed that 38.3% were classified as category C, 37.6% as category B, 13.5% as category D, and 10.5% as category A. Findings demonstrated that ABUS exhibited higher sensitivity than mammography, particularly in women with dense breasts, and detected a greater number of lesions. The overall accuracy of ABUS was 61.65%, representing a statistically significant difference compared to mammography. No significant associations were observed between ABUS-detected lesions and demographic characteristics except for breast density. In conclusion, ABUS shows substantial potential as an effective screening modality, offering improved lesion detection in dense breast tissue and demonstrating advantages over mammography in sensitivity and diagnostic performance.
The Efficiency of FLAIR-Weighted BLADE in image Quality Parameter Correction for Moved Patient
(Al-Quds University, 2023-03-11) maram mohammad motee ghazawna; مرام محمد مطيع غزاونة
Magnetic resonance imaging (MRI) is a medical tool that can provide detailed information about the inner structure of a person's body. The use of the fluid-attenuated inversion recovery (FLAIR) sequence in imaging the brain is very useful, as it can help identify subtle changes in the brain's structure and function. Due to the sensitivity of MRI to artifacts, it is not always possible to achieve high-quality imaging. The presence of motion artifacts can affect the overall diagnostic value. In this study dipole filling for k-space (BLADE) was implemented for 46 different images with different motion types including right rotation, left rotation, right bending, left bending, flexion, extension, and combination. In this work, we aimed to measure signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and percentage of signal ghosting (PSG). RADIANT DICOM viewer was used to calculate signal intensity (SI) and its standard deviation (SD), the SD is used as the noise index. ImageQC was used to calculate PSG while these measurements are plotted in Microsoft Excel. In this research, we used a control group of 46 patients who have standard images which use the cartesian filling for k-space for comparing the measurements with standard FLAIR sequence. Results showed using BLADE lead to a significant improvement in SNR, CNR, and ghosting in almost all types of motion while failing to correct ghosting from severe patient motion. The mean value of SNR was 1.08 for the dipole filling (BLADE) sequence and significantly reduced to 0.92 for the routine sequence (p<0.05). While the mean CNR was 0.75 for dipole filling and significantly reduced to 0.49 for routine sequence (p<0.05). Finally, the mean PSG for dipole filling was 0.75 and significantly reduced to 0.18 for routine sequence (p<0.05). In conclusion, the dipole filling sequence enhances SNR, and CNR due to flow and eye motion. Although BLADE reduced ghosting artifacts in most types of motion, BLADE was unable to eliminate ghosting appearance from the severe patient motion. التصوير بالرنين المغناطيسي (MRI) يوفر معلومات مفصلة حول التشريح الداخلي لجسم المريض, ويعد استخدام بروتوكول تثبيط اشارة السوائل (FLAIR) ذو أهمية في تصوير الدماغ حيث يساعد على التمييز بين السوائل وامراض الدماغ, ومع الأسف ليس من الممكن الحصول على صورة تشخيصية في جميع الحالات نظرا لحساسية التصوير بالرنين المغناطيسي لحركة المريض هذه الحركة تؤثر على القيمة التشخيصية للصورة, في هذه الدراسة نسعى لدراسة أثر الملء القطبي للبيانات ل 46 صورة تم تصويرها ب حركات مختلفة بحيث تشمل هذه الحركات دوران لليمين, دوران لليسار, انحناء لليمين, انحناء لليسار, انحناء للأمام, وانحناء للخلف. قمنا في هذه الدراسة بحساب نسبة التباين, نسبة الإشارة الى التشويش, ونسبة الإشارة الوهمية. حيث تم استخدام برنامج RADIANT DICOM لقياس كثافة الإشارة والانحراف المعياري للإشارة, ويستخدم الانحراف المعياري كمؤشر على كمية التشويش. استخدمنا أيضا في هذه الدراسة برنامج imageQC لحساب نسبة الإشارة الوهمية. تم تسجيل النتائج على برنامج مايكروسوفت اكسل وتمت مقارنتها ب 46 صورة تم اجرائها بالبروتوكول المعياري الذي يستخدم الملء الخطي للبيانات, أظهرت النتائج تحسنا في نسبة الإشارة الى التشويش ونسبة التباين, بالإضافة الى حل مشكلة الإشارة الوهمية الناتجة عن تدفق السائل النخاعي وحركة رموش العين بينما لم يتم تصحيح الإشارة الوهمية الناتجة عن الحركات المتكررة للمريض, كان متوسط نسبة الإشارة الى التشويش في الصور التي تم اجرائها باستخدام الملء القطبي 1.08 بينما صور الملء الخطي 0.92 حيث يعتبر فرق ذو دلالة إحصائية عند قيمة احتمالية اقل من 5%, وبالنسبة لنسبة التباين لصور الملء القطبي 0.75 وانخفض الى 0.49 في صور الملء الخطي ويعتبر هذا فرق ذو دلالة إحصائية عند قيمة احتمالية اقل من 5%. ختاما نسبة الإشارة الوهمية 0.75 في صور الملء القطبي وانخفض الى 0.18 في صور الملء الخطي حيث يعتبر هذا فرق ذو دلالة إحصائية عند قيمة احتمالية اقل من 5%. ونستنتج ان الملء القطبي يعزز نسبة التباين ونسبة الإشارة الى التشويش ويحل مشكلة الإشارة الوهمية الناتجة عن تدفق السائل النخاعي وحركة العين بينما يفشل في حل مشكلة الحركات المتكرة.
Evaluating the Accuracy of 128-Section Multi-Detector Computed Tomography (MDCT) in Detecting Coronary Artery Stenosis
(Al-Quds University, 2022-05-22) Mutasem Mohammad Rafiq Kmail; معتصم محمد رفيق كميل
تعتبر أمراض الشرايين التاجية من الأمراض الرئيسية المسببة للوفاة في جميع أنحاء العالم. يتم استخدام العديد من التقنيات لتشخيصهم واكتشافهم بما في ذلك التقنيات التداخلية وغير التداخلية (الجراحية وغير الجراحية). الطريقة التداخلية (القسطرة): هي عملية جراحية تعتمد على شق جراحي من الجلد يتم عن طريقه الوصول الى الشرايين التاجية. تعد هذه الطريقة المعيار الذهبي في تشخيص أمراض الشرايين التاجية. على الجهة المقابلة، تتسبب القسطرة في آثار جانبية متعددة للمرضى والتي يجب محاولة تجنبها خصيصاً عند من يعانون من اضطرابات في التخثر واضطرابات في الأوعية الدموية. بناءً على ذلك، هناك ضرورة ملحة لإيجاد طرق ذات أضرار جانبية أقل في الوقت الذي يمكن الاعتماد عليها في تقييم أمراض الشرايين التاجية . يعد التصويرالمقطعي المحوسب متعدد الكاشفات المكون من 128 قسمًا (128-slice MultiDetector CT scan) أحد أهم الطرق غير الجراحية وأكثرها شيوعًا, حيث يساعد في تقييم حالة الشرايين التاجية. هناك حاجة ملحّة لتقييم مدى دقة التصوير المقطعي في اكتشاف أية تغيرات مرضية في الشرايين التاجية من أجل إحلال التصوير المقطعي كبديل عن تصوير الأوعية التاجية بالطريقة التداخلية لتجنب المخاطر المحتملة. لذلك، تهدف هذه الدراسة إلى تقييم دقة التصوير المقطعي في اكتشاف أمراض الشرايين التاجية، ولتحقيق ذلك، تم جمع تقارير التصوير المقطعي و تقارير عمليات القسطرة الشريانية لـ 65 مريض من أجل دراستهم ومقارنة نتائجهم. قمنا باستخدام مقاييس إحصائية مختلفة لحساب دقة جهاز التصوير المقطعي مثل: حساسية المعيار والنوعية للمعيار والقيمة الإيجابية المتوقعة والقيمة السلبية المتوقعة للمعيار. أظهرت النتائج التي تم الحصول عليها أن التصوير المقطعي يتمتع بدقة عالية مع قيم عالية لكل من الحساسية والنوعية وقيمة التنبؤية الايجابي وقيمة التنبؤية السلبية. بعض النتائج اظهرت ان نتيجة القسطرة مغايرة لنتيجة التصوير المقطعي المحوسب متعدد الكاشفات المكون من 128 قسمًا لعدة اسباب منها: ضعف التعتيم (الماده الملونه) أو ضبابية الحركة(حركة النبض). نستنتج أن التصوير المقطعي المحوسب متعدد الكاشفات المكون من 128 قسمًا يمكن أن يحل محل القسطرة خاصة للمرضى الذين لا يستطيعون إجراء العمليات الجراحية التداخلية أو الذين يعانون من اضطرابات في التخثر أو الأوعية الموسعة المشوهة.
Evaluation of Exposure to Electromagnetic Fields from MRI Facilities
(Al-Quds Univeersity, 2025-12-13) Noor Malek Ali Ghazawneh; نور مالك علي غزاونة
Clinical practice worldwide widely uses Magnetic Resonance Imaging (MRI) as a crucial diagnostic tool. MRI generates high-resolution images of tissues and organs by combining strong static magnetic fields (SMFs) with radiofrequency electromagnetic fields (RF-EMFs). This technique provides essential information for diagnosis, treatment planning, and patient monitoring. Although MRI is indispensable in clinical imaging, short-term exposure to strong SMFs may cause dizziness, nausea, vertigo and blurred vision. The World Health Organization (WHO) classifies long-term exposure to RF fields as possibly carcinogenic (Group 2B), while current evidence does not indicate that MRI-related SMF exposure causes cancer. These considerations indicate that there must be careful assessment and monitoring of electromagnetic field exposure in MRI facilities. This study aimed to evaluate occupational exposure to SMFs and RF electromagnetic fields in selected MRI facilities across the West Bank, Palestine. Measurements were conducted in four hospitals, which were coded for clarity and consistency throughout the study: H1 refers to the Bethlehem Arab Society for Rehabilitation (Bethlehem) operating a 1.5 T MRI scanner; H2 represents the Moscow Medical Center (Bethlehem) with a 0.55 T MRI system; H3 corresponds to the Palestine Medical Complex (Ramallah) equipped with a 1.5 T MRI scanner; and H4 denotes Al-Rahma Medical Center (Nablus), operating a 3T MRI system. RF field measurements were performed using the Spectrum Rider FPH (Rohde & Schwarz), while static magnetic fields were measured using the Spectran NF-5035 (Aaronia). Data collection followed the American College of Radiology (ACR) zoning classification and was carried out within the MRI scanner rooms and the surrounding safety zones (Zones I–IV). The results indicated that SMF levels ranged from 335 to 1100 µT across all hospitals, with the highest values recorded near the MRI scanner (Zones III–IV, ~1 m from the bore) and the lowest values observed in peripheral areas outside the facility (Zone I, ~20 m). Intermediate exposure levels were measured in patient waiting areas (Zone II, 5–8 m). All measured SMF values were well below the ICNIRP occupational exposure limit of 2 T. RF field strengths varied between 30 and 95 dBµV/m across different sequences and examinations, with higher exposure consistently observed near the bore (Zone IV) and lower levels in seating and waiting areas (Zones I–II). Central body examinations, such as pelvic, pituitary, and abdominal MRI, exhibited the highest RF exposure—particularly in Hospital H3—while peripheral examinations (knee, shoulder, and spine) showed lower levels. T2-weighted and FS/T2 sequences produced the highest RF exposure, whereas T1 and PD sequences resulted in the lowest levels. All RF exposure values remained far below the ICNIRP occupational limit of 61.4 V/m, confirming compliance with international safety standards. Regular monitoring, effective shielding, and adherence to safety protocols are recommended to maintain these safe conditions, particularly as MRI technology advances toward higher field strengths.
Evaluation of optimal contrast-enhanced CT scan for Pulmonary Angiography in Palestinian Health System
(Al-Quds University, 2024-04-03) Ahmad Fathi Ali Alyan; احمد فتحي علي عليان
Computed tomography (CT) technology became one of the gold standard diagnostic modalities all around the world. During the last decade, many advances reveal to new angiographic procedures in CT in shorter exam time and higher image quality. Adequate timing in CT angiography of the Pulmonary Arteries considered vital to the accuracy of the diagnosis of pulmonary embolism. Purpose: The overall aim of this research is to assess the optimal contrast -enhanced CT scan for Pulmonary Angiography in Palestinian Health System The main objectives of this research are: Determine the optimal contrast media enhancement of the pulmonary trunk and descending aorta according to the hospital examined, the gender, and the age of the patient. To determine the accuracy of scanning the pulmonary trunk and descending aorta according to the hospital examined, the gender, and the age of the patient. Methodology A retrospective cross-sectional study was performed to evaluate the optimal contrast enhanced Computed tomography of pulmonary angiography of 285 patients who underwent the exam to role out pulmonary emboli. Data was collected using the picture archiving and communication system from all eight governmental hospitals in the West Bank. SPSS Statistical Package for Social Sciences was used to analyse the collected data according to gender, age group, optimal enhancing, and image accuracy in addition to hypothesis testing. Results Data analysis reveals that optimal enhancement percentage was consistently observed at 75%, encompassing 214 patients. In contrast, 7% of cases, representing 21 patients, were rendered unsuitable for evaluation due to suboptimal enhancement. Notably, a significant proportion, 62% of patients, demonstrated high diagnostic accuracy, with 11% yielding lower accuracy. The pronounced variation in the performance of these hospitals, with Jenin Hospital emerging as the standout contender in both timing enhancement and diagnostic accuracy. A remarkable 19.3% of cases within Jenin Hospital achieved optimal enhancement, showcasing an extraordinary 17.5% high accuracy rate, significantly outperforming other departments. This achievement at Jenin Hospital could be attributed to a fine-tuned protocol of optimal enhancement and high accuracy through the meticulous use of time bolus tracking. In our study of contrast media volume. Through our investigation, we revealed that the use of contrast media at Jericho Hospital had the highest recorded contrast volume of 110 cc. Alia Hospital reported the smallest contrast media volume, weighing in at a mere 50 cc. This contrast in the volume of contrast media used highlights the significant variability in approaches to pulmonary artery CT angiography across these medical institutions. Analyzing the flow rate of contrast media (cc/sec), tThe data clearly depicted that Salfit and Ramallah Hospitals, with their adoption of a flow rate of 5 cc/sec, reigned supreme in this domain. This was a stark contrast to Jenin Hospital, where the flow rate dipped to 3 cc/sec, emerging as the lowest among all the hospitals under examination. Conclusion The current study's research emphasizes the critical role played by contrast media enhancement ratios, CM volume, injection rate, and timing protocols in the accuracy and effectiveness of pulmonary artery CTPA in Palestinian government hospitals. The wide variation in results between these hospitals suggests that there is room for further standardization and improvement in the use of alternative medicine. Our findings not only advance knowledge in this field, but also provide valuable insights for clinicians and medical practitioners, ultimately benefiting patient care and treatment outcomes.
Evaluation of Organs Absorbed Doses, effective dosesand Cancer risk Following Chest HRCT Scan for COVID-19 Patients
(Al-Quds University, 2024-05-24) Hala Yousef Hussein Ahmad Dar-Rabee; هاله يوسف حسين احمد دار ربيع
CT imaging is an effective modality for diagnosing a wide range of medical conditions. CT outperforms x-rays in terms of 3D image generation and soft tissue visualization. CT imaging of the lungs is an important diagnostic tool in the fight against pneumonia. The use of the HRCT imaging protocol for the chest has increased during the COVID-19 pandemic. It is possible to use CT scans for both diagnostic and screening purposes. Radiation risk must be considered, and the dosimetric effects of chest HRCT must be assessed. CT imaging could assist with the early detection of COVID-19-related interstitial pneumonia. There is no agreement on the use of CT for diagnosis due to the first stage of the disease can be negative. So, this study aims to evaluate the dosimetric impact of HRCT of the chest for COVID-19 Patients. The mean organ and effective doses will be evaluated. Also, estimation of radiation cancer risk in (lung, stomach, colon, thyroid, and breast) associated with these exposures according to the Biological Effects of Ionizing Radiations (BEIR) VII report. The study's goal was achieved through the use of quantitative retrospective cohort analysis. The study population consists of 49 adult patients (31 males and 17 females), aged 18 to 89 years, who underwent HRCT during the period between April 26th, 2020, and March 20th, 2021. Data was collected using a local picture archiving and communication system (PACS), including patient demographics and anthropometrics, as well as dose descriptive information (CTDIv and DLP). The effective dose was calculated using two methods: first, using the tissue conversion coefficient (k) for the chest CT, and second, using the VirtualDose™ CT software, which also calculates the organ absorbed dose. The software is based on a large database of organ doses generated via Monte Carlo (MC) simulations using a library of 25 anatomically realistic phantoms. Then The life time attributable risk (LAR) of developing cancer in a specific organ (T) was determined by risk coefficients obtained from Biological Effects of Ionizing Radiations (BEIR) VII report. Each dosimetric parameter is defined by its mean, median, standard deviation, and 75th percentile. We used the MV for comparing our results with previously reported values. The mean value of equivalent doses and the cancer risk probability for organs have been established for either or both gender groups. Spearman’s rank-order test was used to test for correlations between, DLP\BMI, EDDLP, and EDMC. The significance level was defined as p < 0.05. The results of the study revealed that the average calculated effective dose for total population 9.7 mSv, and the average effective dose estimated by virtual dose CT software was 13.47 mSv, with female average dose higher than male with a value of 14.75 and 12.7 mSv respectively. The result showed a decreased effective dose for patients with increased patient BMI while increased with increased DLP. Females showed a higher organs dose than males for all organs as well as cancer risk except for colon, the highest risk were found in lungs for both gender as it 51.6 per 100.000 for females and 21.8 per 100.000 per males.it was concluded that the current chest HRCT protocol result in significant radiation doses to the patients compared to reported in previous studies

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