Iranian Journal of Medical Physics
Volume:20 Issue: 4, Jul-Aug 2023

Radioactive contamination by uranium and its emissions, such as alpha particles, is considered one of the most critical issues affecting the human race and its existence. The study investigated the high ionization capacity number of alpha particles in whole blood samples from cancer patients because these particles have the most significant impact on the shape and function of living cells, modifying them into malignancies.
The TASLImage solid nuclear trace detector CR-39 was used to measure the effects of alpha emitters in the whole blood samples from 40 cancer patients for five types of cancer (breast, uterus, prostate, kidney, and colon) collected from a government hospital at Karbala/Iraq and compared with ten healthy samples. Moreover, the research investigated whether smoking and gender variation affect the outcomes.
The radon concentration in whole blood samples from patients and healthy individuals was significantly different (p< 0.05), and it was slightly higher in males with (22.82254±7.38794 Bq/m3). Women with colon cancer had higher blood levels of radon (32.13787±5.79261 Bq/m3) than men with the same malignancy (18.80531±5.63747 Bq/m3), regardless of gender. While the age factor had no noticeable impact, the smoking element had a considerable effect (p< 0.05).
All alpha levels were within the (ICRP) usual ranges. Women with colon cancer had the most significant alpha values. In contrast, men with the same disease had the lowest values despite cancer patients' blood levels being higher than those of the healthy group.

To determine radiotherapy accuracy and prevent treatment errors, quality assurance is crucial during the planning phase of radiation therapy. Therefore, the goal of this study was to create criteria for the routine quality control assessment of radiation treatment planning systems TPS to assess their effectiveness and accuracy.
In this study, we used a Prowess Panther treatment planning system TPS (version 5.51), a Siemens model Somatom Confidence computed tomography simulator, an anthropomorphic Alderson-Rando phantom, and a density phantom made from a CTDI head phantom by inserting plugs that mimicked human tissue. The TPS features include hardware, transmitted CT images (anatomical information), and key software operations; however, in this investigation, we focused exclusively on the tests involving anatomical information.
The Prowess Panther RTPS version 5.51 workstation consistently met the requisite quality where all results of the radiation treatment planning systems (Prowess Panther RTPS) anatomical information tests were satisfactory and acceptable.
By averting several radiation-related events, the recommendations for TPS CT image quality control testing made in this study will assist to increase the safety and effectiveness of cancer radiotherapy.

To implement the newly introduced concept volume of Definite Target Volume (DTV) and compare the distribution and dose-escalation in the DTV and clinical plans. We used seven samples of hepatocellular carcinoma (HCC) and three cervix tumour plans. DTV is determined through occupancy probability and margin contraction. This margin reduces the Clinical Target Volume (CTV) to obtain the DTV volume. DTV optimisation was achieved by giving the maximum dose to the target volume and limiting the organ at risk (OAR) by constraint. The DTV volume is obtained with a range of 60.8–913.9 cc for HCC and 2.4–22.9 cc for the cervix tumour. In HCC, the average at DTV volume increased to 124.98 ± 29.02, whereas the average  increased to 105.36% ± 2.66% for the Planning Target Volume-crop (PTV-crop). For cervix tumour cases, the highest dose on DTV volume reached 138.49%, and the average  at DTV volume increased to 116.80% ± 13.19%. In addition, the average  increased to 101.89% ± 5.58% for the PTV-crop. A larger dose delivered at the DTV will be associated with an increase in OAR. The dose increase of OAR-HCC is 106.93% ± 5.57%, and OAR-cervix is 101.18% ± 1.87%. The larger margins generate smaller DTV volumes or vice versa. The dose to target DTV has increased considerably, but dose increases to PTV-crop and OAR are still within clinically acceptable levels.

The optimization of radiation exposure when exploring small and complex anatomical structures is the most important issue for temporal bone CT. The objective of this study is to use single-shot volume acquisition in order to minimize the dose and compare the obtained image quality to a conventional helical technique.  Twenty patients (8 males, 12 females) were scanned using the 135kVp single-shot volume mode (VMCT135-kVp) whereas other twenty patients (9 males, 11 females) were examined using the 120kVp helical mode (HMCT120-kVp). A physician-interpreter evaluated the subjective conspicuity of 53 structures in the temporal bone on a 5-point scale using multiplanar reconstruction (MPR). In addition, the image noise in both techniques was quantified by analyzing it in three different regions of interest (ROIs). Radiation dose reduction was noted and compared with literature-based effective dose dosimetry data. The mean dose-length-product (DLP) for the VMCT135-kVp was (69.6±2.5 mGy.cm), which was significantly lower (p<0.001), compared to (186.4±4.3 mGy.cm) for HMCT120-kVp. Similarly, the effective dose (0.15±0.01 mSv) for VMCT135-kVp was reduced by approximately 61.5% relative to (0.39±0.05 mSv) for HMCT120-kVp. In contrast, there was no significant difference in the image noise average between the two protocols (p> 0.05). Indeed, the overall analysis of the 53 anatomic structures revealed no differences between the two protocols, and most anatomic structures were identified. For temporal bone, the VMCT135-kVp scan significantly reduces radiation exposure compared to the HMCT120-kVp. The obtained dose was lower compared to the literature-based protocol while maintaining image visualization quality.

The main aim of the study was to find the most common CT feature in the lungs of patients associated with Delta variant and characterize thoracic computed tomography and report mortality.
A total of 156 patients with suspected or confirmed COVID-19 infection were randomized in this study which their chest CTs performed at the initial positive and negative RT-PCR. There were two groups of patients involved.
The patients had typical imaging features such as; coagulation (33 [21.2%]), ground glass opacities (GGO) (140 [89.7%]), vascular enlargement of the lesion (41 [26.3%]). Lesions that appear on CT images are more likely to have peripheral distribution (79 [50.6%]), peripheral and central distribution (61 [39.1%]) and architectural distortion (14 [9%]. Other CT features include pleural effusion (15 [9.6 %]) and crazy-paving pattern (25 [16 %]). Only two patients had tree-in-bud and traction bronchiectasis (2 [1,3%]). In contrast, the overall mortality rate was (19 [12.2%]).
The most common CT feature was peripheral GGO (140 [89.7%]) in the lungs of patients with COVID-19. The initial positive RT-PCR group had a higher peripheral distribution, GGO, and frenzy pattern during their CT scan than patients in the group with a negative initial RT-PCR result. Mortality rates were nearly identical between groups with a positive and negative RT-PCR baseline at 10.7% and 13%, respectively. It has been shown that most patients with negative RT-PCR should be considered suspected of having COVID-19.

Early-stage glottic cancer has a high cure rate with definitive radiotherapy. Historical reports show excellent local control. The present study evaluated the outcomes of early glottic cancer patients treated with a hypofractionated radiotherapy schedule of 60Gy in 20 fractions. This is a retrospective study of patients with stage I glottic cancer who received radical intent LINAC-based hypo-fractionated 3D conformal radiotherapy with a dose 60Gy in 20 fractions. The primary objective was to assess the locoregional control (LRC), and secondary objectives were to determine disease-free survival (DFS), overall survival (OS), and toxicity. The analysis included 105 patients from the age range of 35-88 years. About 69% of patients were over 60 years of age. The median overall treatment time (OTT) was 26 days (24 – 30 days). The mean follow-up was 74 months, ranging from 9 to 135 months. Seven patients had locoregional recurrence after an initial complete clinical response. Six had local, and one had a regional nodal recurrence. DFS at five years and ten years were 83% and 69%, and OS at five years and ten years were 87% and 80%, respectively. Most patients reported grade I skin reactions and tolerated the treatment well. We did not observe any late adverse events such as persistent laryngeal edema or radiation necrosis. The radiotherapy schedule of 60Gy in 20 fractions over four weeks offers comparable local disease control with reasonable long-term side effects in T1 glottic cancer.

Accurate segmentation of brain tissue in magnetic resonance imaging (MRI) is an important step in the analysis of brain images. There are automated methods used to segmentation the brain and minimize the disadvantages of manual segmentation, including time consuming and misinterpretations. These procedures usually involve a combination of skull removal, bias field correction, and segmentation. Therefore, segmented tissue quality assessment segmentation of gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) is required for the analysis of neuroimages.
This paper presents the performance evaluation of three automatic methods brain segmentation, fluid and white matter suppression [FSL, Freesurfer (FreeSurfer is an open source package for the analysis and visualization of structural, functional, and diffusion neuroimaging data from cross-sectional and longitudinal studies) and SPM12 (Statistical Parametric Mapping)]. Segmentation with SPM12 was performed on three tissue probability maps: i) threshold 0.5, ii) threshold 0.7 and iii) threshold 0.9. In order to compare and evaluate the automatic methods, the reference standard method, i.e., manual segmentation, was performed by three radiologists.
Comparison of GM, WM and CSF segmentation in MR images was performed using similarities between manual and automatic segmentation. The similarity between the segmented tissues was calculated using diagnostic criteria.
Several studies have examined the classification of GM, WM, and CSF using software packages. In these studies, different results have been obtained depending on the type of method and images used and the type of segmented tissues. In this study, the evaluation of the segmentation of these packages with reference standard method is performed. The results can help users in selecting an appropriate segmentation tool for neuroimages analysis.

Breast cancer can be caused by a mutation in its genome. Some mutations are cancer-predisposition which exist at the moment of germ cell genesis. It has been discovered that BRCA1 and BRCA2 are linked to hereditary breast cancer. BRCA1/2 are tumor suppressor genes involved in DNA repair and transcriptional regulation in response to DNA damage. Irradiation, particularly ionizing radiation used in clinical radiotherapy, causes DNA damage. This study aims to find out whether different doses of x-radiation might change the expression of BRCA1/2.
Cancer and normal breast cell lines (MCF10-A and MCF7) cultured in flasks were irradiated with X- rays in different doses including 50, 100, 400, 2000, and 4000 mGy. Then, the expression of BRCA1/2 genes was measured using real-time quantitative reverse transcription PCR (RT-qPCR). Relative changes for mRNA were calculated based on the ∆∆Ct method.
MCF-10A cells represent a significant increase in BRCA2 expression at all irradiation doses while increasing the mRNA level for the BRCA1 gene observed after exposure to 50, 100, and 2000 mGy. This figure shows overexpression of BRCA2 gene after all irradiation doses except 100 mGy for MCF7 cells. The BRCA1 gene upregulated after exposure to 400 and 2000 mGy and downregulated at 50,100 and 4000 mGy in these cells.
Incidence of cancer initiation was probable in normal breast cells after low-dose radiation, with up-regulation of BRCA1 and BRCA2 gene expression. BRCA mutation may be an inadequate outcome predictor of survival rate and other factors may be involved too.