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The paper discusses the ASG EUPOS services. It assesses the possibility of using this system selected sites in hydrography and off-shore navigation tasks. The experiments presented and analyzed in the paper were carried out in the port of Gdynia and on the Gulf of Gdańsk. The results confirm that the ASG EUPOS services guarantee positioning accuracy. The obtained accuracy greatly exceeds the needs and requirements of coastal navigation and underwater mining and sea bottom exploration. [ABSTRACT FROM AUTHOR]

Purpose: Medical imaging is one of the main methods of diagnosing COVID-19, along with real-time reverse trans-cription-polymerase chain reaction (RT-PCR) tests. The purpose of the study was to analyse the texture parameters of chest X-rays (CXR) of patients suspected of having COVID-19., Material and Methods: Texture parameters of the CXRs of 70 patients with symptoms typical of COVID-19 infection were analysed using LIFEx software. The regions of interest (ROIs) included each lung separately, for which 57 para-meters were tested. The control group consisted of 30 healthy, age-matched patients with no pathological findings in CXRs., Results: According to the ROC analysis, 13 of the tested parameters differentiate the radiological image of lungs with COVID-19 features from the image of healthy lungs: GLRLM_LRHGE (AUC 0.91); DISCRETIZED_Q3 (AUC 0.90); GLZLM_HGZE (AUC 0.90); GLRLM_HGRE (AUC 0.89); DISCRETIZED_mean (AUC 0.89); DISCRETIZED_Q2 (AUC 0.61); GLRLM_SRHGE (AUC 0.87); GLZLM_LZHGE (AUC 0.87); GLZLM_SZHGE (AUC 0.84); DISCRETIZED_Q1 (AUC 0.81); NGLDM_Coarseness (AUC 0.70); DISCRETIZED_std (AUC 0.64); CONVENTIONAL_Q2 (AUC 0.61)., Conclusions: Selected texture parameters of radiological CXRs make it possible to distinguish COVID-19 features from healthy ones., Competing Interests: The authors report no conflicts of interest., (© Pol J Radiol 2024.)

The goal of this phase II trial was to evaluate safety and efficacy of a tandem autologous hematopoietic cell transplantation (auto-HCT) using sequentially total marrow irradiation (TMI) at the dose of 12 Gy (4 Gy on days -3, -2, and -1) and melphalan 200 mg/m 2 for patients with multiple myeloma (MM). TMI was performed using helical tomotherapy. Additional "boosts" (total 24 Gy) were applied for patients with active lesions as revealed by PET-FDG. Fifty patients with median age 58 years (41-64 years) were included and received tandem auto-HCT. TMI resulted in absolute neutropenia in all patients. Grade 3 infections were reported in 30% patients. Other toxicities were rare. Proportion of patients who achieved at least very good partial response increased from 46% before the first auto-HCT to 82% after tandem transplantation. Complete remission rates changed from 10% to 42%, respectively. The probabilities of overall and progression-free survival at 5 years were 74% and 55%, respectively. No patient died without progression. We conclude that conditioning with TMI ± PET-guided "boosts" represents personalized treatment approach in MM and is characterized by very good toxicity profile. Tandem auto-HCT using TMI in sequence with high-dose melphalan appears safe with encouraging early efficacy.

Aim: The aim of this study is to answer the question whether the calculated dose distributions for HD and Millennium collimators (Varian Medical Systems) are equivalent for large treatment volumes., Background: Modern biomedical linacs are equipped with multileaf collimators where leaves can be of different widths. Thinner leaves allow better fit to desired (tumor) shape. At the same time, however, the maximum size of the field that can be obtained with the collimator is also reduced. Varian Medical Systems HD and Millennium collimators can be a good sample. They have 40 cm or 22 cm × 40 cm maximal field size at the isocenter, respectively., Materials and Methods: This paper presents the comparison of selected statistical and dosimetric parameters achieved for treatment plans where the beams for a HD collimator had to be merged because of the size of the tumor volume., Results and Discussion: Achieved results show that, independently from irradiated volume, there is no statistically significant difference for calculated dose distributions, integral doses, MU values and coefficients evaluating dose distributions for HD and Millennium collimators., Conclusions: Results show that both types of collimators can be used interchangeably for preparing the treatment plans for large tumor volume without quality reduction of the prepared treatment plan.

Abdominal aortic aneurysm (AAA) is defined as a localized enlargement of the aortic cross-section where the diameter is greater than 3 cm or more than 50% larger than the diameter in a normal segment. The most important complication of AAA is rupture, which, if untreated, results in mortality rates of up to 90%. Conventional open surgical repair is associated with significant 30-day mortality. Endovascular aneurysm repair (EVAR) is a significantly less invasive procedure; it is related to a lower early mortality rate and a lower number of perioperative complications. Although EVAR is a minimally invasive technique, lifelong follow-up imaging is necessary due to possible late complications including endoleak, recurrent aneurysm formation, graft infection, migration, kinking and thrombosis. The total rate of complications after EVAR is estimated at approximately 30%, and the rate of complications that require intervention is 2-3%. Early detection and progression analysis of such situations is crucial for proper intervention.

Atherosclerotic disease is currently one of the most important problems of modern medicine because it is a leading cause of increased morbidity, morbidity and mortality, and disability in the Western World. Atherosclerosis of the lower limbs (peripheral arterial disease - PAD) significantly affects the quality of life and in a considerable proportion of patients is a cause of disability. Radical treatment of PAD, both surgical and endovascular, aims at revascularisation of ischaemic tissues distal to obstructed arteries. Surveillance imaging is an important part of patient management after endovascular repair of PAD. Apart from availability and contraindications, challenges of imaging include calcifications, flow dynamics, and stent-related artefacts. The aim of this paper was to review the current literature on imaging methods for follow-up after endovascular repair of atherosclerotic lesions, with special attention paid to novel techniques. As a non-invasive modality, ultrasound is still the first-line examination, but computed tomography angiography remains a current state-of-the art technique for follow-up. However, since current imaging recommendations seem not to adhere to contemporary imaging possibilities, more attention should be paid to recent improvements in magnetic resonance angiography technology., Competing Interests: The authors report no conflict of interest.

Purpose: Computed tomography remains the first-choice modality for assessment of colorectal cancer liver metastases (CRLM). Dual-energy computed tomography (DECT) is a relatively new technique that is becoming increasingly available. One of the advantages of DECT is the ability to maximise iodine detection. Our aim was to test whether single-source, fast kVp-switching DECT can improve imaging quality of CRLM compared to conventional (polychromatic) CT., Material and Methods: Twenty consecutive patients were enrolled into a preliminary prospective study. The scanning protocol consisted of four phases: non-contrast with standard 120 kV tube voltage and three post-contrast phases with rapid voltage switching. As a result, three sets of images were reconstructed: pre- and postcontrast polychromatic (PR), monochromatic (MR), and iodine concentration map (IM). To compare the sensitivity of the tested reconstructions, the number of CRLMs and the maximum diameter of the largest lesion were calculated. Objective image quality was measured as signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). The radiation dose was expressed as CTDI vol ., Results: Imaging was successfully performed in all patients. The number of detected lesions was significantly lower on PR images than on IM and MR 50-70 keV (mean number: 4.20 and 4.45, respectively). IM and MR at 70 keV presented the highest quality. SNR was significantly higher for IM and 70 keV images than for other reconstructions. The mean radiation dose was 14.61 mGy for non-contrast 120 kV scan and 17.89 mGy for single DECT scan ( p < 0.05)., Conclusions: DECT is a promising tool for CRLM imaging. IM and low-photon energy MR present the highest differences in contrast between metastases and the normal liver parenchyma.

Purpose: Obesity is a well-known of risk factor for atherosclerosis. However, recently an "obesity paradox" has been discussed, which is considered as a protective effect of obesity on the development coronary artery disease (CAD). An aim of the study was to investigate the risk of CAD in morbidly obese patients using coronary artery calcium measurement., Material and Methods: Fifty-one patients with morbid obesity (BMI ≥ 40 kg/m 2 ) and thirty controls were scanned to determine the amount of coronary artery calcification (CAC), which was expressed as calcium score (CS) and coronary age (CA). The control group consisted of patients scanned for the clinical suspicion of CAD, who did not fulfil the criteria of obesity., Results: Mean BMI of obese patients and controls was 47.3 and 26.5, respectively ( p < 0.0001). Arterial hypertension, dyslipidaemia, and smoking were more frequent in the control group than in the obesity group ( p < 0.02). The prevalence of CAC was higher in the obesity group (53% vs. 23%, p < 0.01). The groups did not differ regarding CS and CA. However, the difference between coronary age and metrical age was higher in obese patients than in controls (+5.6 vs. -4.8 years, respectively, p < 0.005)., Conclusions: Patients with morbid obesity present an increased risk of CAD that is reflected by the difference between their coronary age and metrical age.

Purpose: Obesity is a well-known of risk factor for atherosclerosis and the amount of visceral adipose tissue is considered as an independent predictor of coronary artery disease (CAD). An aim of the study was to investigate the distribution of intrathoracic adipose tissue in morbidly obese patients., Material and Methods: Fifty-one patients with morbid obesity (BMI ≥ 40 kg/m 2 ) and thirty controls were scanned in a coronary calcium scoring protocol. Control group consisted of patients scanned due to a clinical suspicion of CAD, who did not fulfill obesity criteria. The amount of adipose tissue was measured as epicardial adipose tissue (EAT) thickness, pericoronary fat (PCF) thickness, total intra-pericardial fat (IPF) volume, and total intrathoracic fat (ITF) volume., Results: Mean BMI of obese patients and controls was 47.3 and 26.5, respectively ( p < 0.0001). Patients with obesity and controls did not differ with respect to mean EAT, mean PCF, and IPF. However, ITF was lower in obesity group than in control group (268 vs. 332 cm 3 , respectively; p < 0.03). Moreover, ROC analysis presented relation between obesity and the superior EAT thickness, PCF at LCX, mean PCF, ITF, and chest soft tissue (CST) thickness ( p < 0.03). CST thickness of > 60 mm was the parameter that presented the strongest association with morbid obesity (AUC 0.95; p < 0.0001)., Conlcusions: Increased chest soft tissue thickness but not the increased intrathoracic adipose tissue volume was associated with morbid obesity. Since the quantity of the pericardiac fat is not directly related to the obesity, its accumulation may be related to a mechanism different than that of subcutaneous adipose tissue growth., Competing Interests: None of the authors declared any conflict of interest.

Purpose: Evaluation of the 18-fluorodeoxy-glucose positron emission tomography-computed tomography (18-FDGPET/ CT) for gross tumor volume (GTV) delineation in gastric cancer patients undergoing radiotherapy. Methods: In this study, 29 gastric cancer patients (17 unresectable and 7 inoperable) were initially enrolled for radical chemoradiotherapy (45Gy/25 fractions + chemotherapy based on 5 fluorouracil) or radiotherapy alone (45Gy/25 fractions) with planning based on the 18-FDG-PET/CT images. Five patients were excluded due to excess blood glucose levels (1), false-negative positron emission tomography (1) and distant metastases revealed by 18-FDG-PET/CT (3). The analysis involved measurement of metabolic tumor volumes (MTVs) performed on PET/CT workstations. Different threshold levels of the standardized uptake value (SUV) and liver uptake were set to obtain MTVs. Secondly, GTVPET values were derived manually using the positron emission tomography (PET) dataset blinded to the computed tomography (CT) data. Subsequently, GTVCT values were delineated using a radiotherapy planning system based on the CT scans blinded to the PET data. The referenced GTVCT values were correlated with the GTVPET and were compared with a conformality index (CI). Results: The mean CI was 0.52 (range, 0.12-0.85). In 13/24 patients (54%), the GTVPET was larger than GTVCT, and in the remainder, GTVPET was smaller. Moreover, the cranio-caudal diameter of GTVPET in 16 cases (64%) was larger than that of GTVCT, smaller in 7 cases (29%), and unchanged in one case. Manual PET delineation (GTVPET) achieved the best correlation with GTVCT (Pearson correlation = 0.76, p <0.0001). Among the analyzed MTVs, a statistically significant correlation with GTVCT was revealed for MTV10%SUVmax (r = 0.63; p = 0.0014), MTVliv (r = 0.60; p = 0.0021), MTVSUV2.5 (r = 0.54; p = 0.0063); MTV20%SUVmax (r = 0.44; p = 0.0344); MTV30%SUVmax (r = 0.44; p = 0.0373). Conclusion: 18-FDG-PET/CT in gastric cancer radiotherapy planning may affect the GTV delineation., (https://www.ncbi.nlm.nih.gov/pubmed/management)

Background: Application of the image-guided radiotherapy (IGRT) system for gastric cancer involving daily verification of patient positioning on the treatment machine allows minimisation of geometrical errors as a consequence of intra- and inter-fraction motion. The purpose of this study was to define the intrafraction motion in gastric cancer patients during a treatment session based on the IGRT system and designation of margins around the clinical target volume CTV (internal target volume ITV) necessary to delineate the planning target volume (PTV). Methods: Twenty gastric cancer patients were analysed. The total radiation dose for each was 45Gy in 25 fractions within 5 weeks. The margins for the PTV were calculated according to van Herk (2004), Stroom and Heijmen (2002) and the International Commission on Radiation Units and Measurements (ICRU) Report 62 formulas based on craniocaudal (Y axis), laterolateral (X axis) and anteroposterior (Z axis) shifts. Results: Delineated margins for the PTV in gastric cancer with the three formulas applied were respectively 0.2, 0.2, and 0.2cm in the lateral plane, 0.3, 0.3, and 0.3cm in the craniocaudal plane and 0.3, 0.3, and 0.2cm in the anteroposterior plane. Conclusions: Recommended margins for the PTV in gastric cancer calculated in this study based on intrafraction motion are 0.3cm, 0.2cm and 0.3cm in the craniocaudal, lateral and anterioposterior directions, respectively. Use of the IGRT system corrects for the motions between factions and allows reduction in ITV-PTV margins. The main advantage of the smaller margins in comparison to the non-IGRT radiotherapy is a reduction in the probability of radiation complications., (Creative Commons Attribution License)

The aim of the present study was to compare the techniques of dynamic intensity-modulated radiation therapy (IMRT) and three-dimensional conformal radiotherapy (3DCRT) in patients with gastric cancer. Implementation of the IMRT technique does not significantly affect the minimum and maximum dose levels in the planning target volume (PTV), but more effectively protects the critical organs. The study group consisted of 25 patients. The results of the analysis of the conformity index (CI) and the homogeneity index (HI) showed that the doses in the PTV regions were at a comparable level. The CI for the PTV was 0.95 for the 2-field technique, 0.95 for the 3-field technique, 0.96 for the 4-field technique and 0.94 for the IMRT technique. The CIs for these techniques for the clinical target volume (CTV) were 0.96, 0.96, 0.97 and 0.96, respectively, and the CIs for the gross tumor volume (GTV) were 0.99, 0.99, 0.99 and 0.98, respectively. The HI values for the PTV were 1.12 for the 2-field technique, 1.12 for the 3-field technique, 1.09 for the 4-field technique and 1.09 for the IMRT technique, and the HI values for the CTV were 1.12, 1.12, 1.09 and 1.08 for the same techniques, respectively. The HI values for the GTV were 1.09, 1.09, 1.07 and 1.06, respectively, which indicated significantly superior performance in the regions of healthy tissue. Statistical study was based on Friedman's rank analysis of variance to determine the level of reliability of the tested groups of variables (P<0.001). The present study demonstrated that the IMRT technique in the pre-operative radiotherapy of gastric cancer patients results in superior treatment tolerance and reduces the risk of damage to healthy tissue that is in close proximity to the irradiated area.

Aim: The purpose of this study was to compare conformal radiotherapy techniques used in the treatment of gastric cancer patients. The study is dedicated to radiotherapy centres that have not introduced dynamic techniques in clinical practice., Background: The implementation of multi-field technique can minimise the toxicity of treatment and improve dose distribution homogeneity in the target volume with simultaneous protection of organs at risk (OaRs). Treatment plan should be personalised for each patient by taking into account the planning target volume and anatomical conditions of the individual patient., Materials and Methods: For each patient, four different three dimensional conformal plans were compared: 2-field plan, 3-field plan, non-coplanar 3-field plan and non-coplanar 4-field plan. Dose distributions in a volume of 107% of the reference dose, and OaRs such as the liver, kidneys, intestines, spinal cord, and heart were analysed., Results: The mean volume of the patient body covered using the isodose of 107% was 3004.73 cm(3), 1454.28 cm(3), 1426.62 cm(3), 889.14 cm(3) for the 2-field, 3-field, non-coplanar 3-field and non-coplanar 4-field techniques, respectively. For all plans the minimum dose in the PTV volume was at least 95% of the reference dose. The QUANTEC protocol was used to investigate doses in OaRs., Conclusions: Comparison of 3D conformal radiotherapy techniques in gastric cancer patients indicates that none of the plans can fulfil simultaneously all of the criteria of the tolerance dose in the organs at risk. The implementation of the multi-field technique can minimise the toxicity of treatment and improve dose distribution homogeneity in the target volume with additional protection of organs at risk (OaRs).

Background: Gastrointestinal tract duplication is a rare malformation associated with the presence of additional segment of the fetal gut. The aim of this study was to retrospectively review clinical features and imaging findings in intraoperatively confirmed cases of gastrointestinal tract duplication in children., Material/methods: The analysis included own material from the years 2002-2012. The analyzed group included 14 children, among them 8 boys and 6 girls. The youngest patient was diagnosed at the age of three weeks, and the oldest at 12 years of age., Results: The duplication cysts were identified in the esophagus (n=2), stomach (n=5), duodenum (n=1), terminal ileum (n=5), and rectum (n=1). In four cases, the duplication coexisted with other anomalies, such as patent urachus, Meckel's diverticulum, mesenteric cyst, and accessory pancreas. Clinical manifestation of gastrointestinal duplication cysts was variable, and some of them were detected accidently. Thin- or thick-walled cystic structures adjacent to the wall of neighboring gastrointestinal segment were documented on diagnostic imaging., Conclusions: Ultrasound and computed tomography are the methods of choice in the evaluation of gastrointestinal duplication cysts. Apart from the diagnosis of the duplication cyst, an important issue is the detection of concomitant developmental pathologies, including pancreatic heterotopy.

Introduction: The use of fiducial markers in patients undergoing teleradiotherapy increases the precision of treatment under the condition that the marker does not displace itself during this treatment. In order to determine the accuracy of the verification method used to establish patient position, it is necessary to establish the possible marker migration range during planning and treatment with radiation therapy., Material and Method: An analysis of the migration of GoldAnchorTM fiducial markers implanted in the prostate conducted on a group of 29 patients treated with image-guided radiation therapy at the Radiotherapy Department of the Cancer Centre and Institute of Oncology in Gliwice. The migration value was determined based on a comparison of the marker's location with the use of spiral computer tomography and cone-beam computer tomography done on the treatment device., Results: The average values of the given fiducial marker's migration in the superior-inferior (SI), left-right (LR) and anterior-posterior (AP) directions were: 0.07 cm (SD=0.1 cm); 0.06 cm (SD=0.07 cm) and 0.11 cm (SD=0.11 cm), respectively. The average value of the displacement vector computed according to the Pythagorean theorem and using the Euclidean norm was 0.17 cm with SD= 0.13 cm., Conclusion: The analysis indicates that migration of markers implanted in the prostate occurs during radiation treatment planning but probably it is not clinically relevant. Because a correlation was determined between the migration value and the time of carrying out the CT as well as the time that had passed from the implantation to the CBCT examination, it is reasonable to start radiation therapy promptly and to control the marker's location during radiation therapy.

Aim: The aim was to provide a dosimetric comparison between IMRT and RapidArc treatment plans with RPI index with simultaneous comparison of the treatment delivery time., Background: IMRT and RapidArc provide highly conformal dose distribution with good sparing of normal tissues. However, a complex spatial dosimetry of IMRT and RapidArc plans hampers the evaluation and comparison between plans calculated for the two modalities. RPI was used in this paper for treatment plan comparisons. The duration of the therapeutic session in RapidArc is reported to be shorter in comparison to therapeutic time of the other dynamic techniques. For this reasons, total treatment delivery time in both techniques was compared and discussed., Materials and Methods: 15 patients with prostate carcinoma were randomly selected for the analysis. Two competitive treatment plans using respectively the IMRT and RapidArc techniques were computed for each patient in Eclipse planning system v. 8.6.15. RPIwin(®) application was used for RPI calculations for each treatment plan. Additionally, total treatment time was compared between IMRT and RapidArc plans. Total treatment time was a sum of monitor units (MU) for each treated field., Results: The mean values of the RPI indices were insignificantly higher for IMRT plans in comparison to rotational therapy. Comparison of the mean numbers of monitor units confirmed that the use of rotational technique instead of conventional static field IMRT can significantly reduce the treatment time., Conclusion: Analysis presented in this paper, demonstrated that RapidArc can compete with the IMRT technique in the field of treatment plan dosimetry reducing the time required for dose delivery.

The IGRT notion (image guided radiation therapy) comprises all techniques enabling checking and correction of patients position directly before or during an irradiation session. In last years they became a standard in radiotherapy due to decreasing of geographical misses. The aim of our study was a comparison of two IGRT techniques--CBCT and 2D-2D kV performed for prostate cancer patients and a comparison of two immobilization systems used for them. The performed analysis comprises 3582 2D-2D kV and 2110 CBCT IGRT measurements made for 85 prostate cancer patients. Patients were irradiated using thermoplastic masks and two kinds of immobilizing plates. One subgroup of patients was treated using leg supports and second one without them. Mean, maximum, minimum and standard deviation of absolute values of shifts (cm) measured using 2D-2D kV were 0.27, 0.0, 2.8 and 0.33 respectively. For CBCT these same values were 0.31, 0.0, 4.1 and 0.33. Mean, maximum, minimum and standard deviation of real shifts values (cm) measured using 2D-2D kV were -0.01, -2.5, 2.8 and 0.43 respectively. For CBCT these same values were 0.01, -4.1, 2.3 and 0.45. Comparison of shift absolute values distributions for whole analyzed group showed statistically significant difference (p=0.001) between 2D-2D kV and CBCT with higher mean for CBCT (0.31 vs 0.27) and equal standard deviations. Statistically significant difference (p=0.000...) between distributions of measurements in z axis was found (for 2D-2D kV mean 0.16, SD=0.21, for CBCT mean 0.25, SD=0.25). Comparison of absolute shifts values distributions revealed significant difference for CBCT, for two immobilization plates--in x (p=0.001) and y axis (p=0.007). For the small plate in x axis mean was 0.22 (SD=0.2), and for the large one (with an integrated head support) 0.17 (SD=0.2). Comparison of absolute shifts values for sub- groups created dependently on the leg support use, showed significant differences in x axis for 2D-2D kV (p=0.000...); mean in the subgroup irradiated without leg supports was 0.14 (SD=0.14) and for the subgroup without them was 0.19 (SD=0.15) and in x axis for CBCT (p=0.03); mean in the subgroup irradiated without leg supports was 0.18 (SD=0.18) and for the subgroup without them was 0.23 (SD=0.22). Significant difference was also revealed for the whole group of absolute shift values for 2D-2D kV (p=0.01). For the subgroup irradiated without leg supports mean was 0.27 (SD=0.34), and for the subgroup treated with them was 0.27 (SD=0.31). Obtained results permit us to conclude that in the case of prostate cancer patients IGRT based on the bone anatomy visualization, the method of choice should be 2D-2D kV, because it allows for more precise and shorter patient position evaluation and, that during IGRT of prostate cancer patients using a simple thermoplastic immobilization system is sufficient; use of more sophisticated systems with additional supports did not improve the patient immobilization.