Different radiographic imaging modalities with a proton computed tomography demonstrator

Abstract Proton computed tomography aims at improving proton-beam therapy, which is an established method to treat deep-seated tumours in cancer therapy. In treatment planning, the stopping power (SP) within a patient, describing the energy loss of a proton in a tissue, has to be known with high accuracy. However, conventional computed tomography (CT) returns Hounsfield units (HU), which have to be converted to SP values to perform the required treatment planning, thus introducing range uncertainties in the calculated dose distribution. Using protons not only for therapy but also for the preceding planning CT enables the direct measurement of the SP. Hence, this imaging modality eliminates the need for further conversion and therefore offers the possibility to improve treatment planning in proton therapy. In order to examine the principles of such a proton CT (pCT) setup, a demonstrator system, consisting of four double-sided silicon strip detectors and a range telescope, was built. The performance of the pCT demonstrator was tested with measurements at the MedAustron facility in Wiener Neustadt, Austria. In this paper, 2D imaging modalities going beyond the idea of a standard proton radiography, will be discussed. Namely, fluence loss imaging and scattering radiography results obtained with the demonstrator will be shown. The advantage of these modalities is that they do not rely on an additional energy measurement and can therefore be conducted only with the tracker of the demonstrator.

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Accuracy of Commonly-Used Imaging Modalities in Assessing Left Atrial Appendage for Interventional Closure: Review Article

Journal of Clinical Medicine ◽

10.3390/jcm7110441 ◽

2018 ◽

Vol 7 (11) ◽

pp. 441 ◽

Cited By ~ 1

Author(s):

Ramez Morcos ◽

Haider Al Taii ◽

Priya Bansal ◽

Joel Casale ◽

Rupesh Manam ◽

...

Keyword(s):

Computed Tomography ◽

Transesophageal Echocardiography ◽

Left Atrial ◽

Left Atrial Appendage ◽

Imaging Modality ◽

Three Dimensional ◽

Atrial Appendage ◽

Imaging Modalities ◽

Three Dimensional Printing ◽

Dimensional Printing

Periprocedural imaging assessment for percutaneous Left Atrial Appendage (LAA) transcatheter occlusion can be obtained by utilizing different imaging modalities including fluoroscopy, magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound imaging. Given the complex and variable morphology of the left atrial appendage, it is crucial to obtain the most accurate LAA dimensions to prevent intra-procedural device changes, recapture maneuvers, and prolonged procedure time. We therefore sought to examine the accuracy of the most commonly utilized imaging modalities in LAA occlusion. Institutional Review Board (IRB) approval was waived as we only reviewed published data. By utilizing PUBMED which is an integrated online website to list the published literature based on its relevance, we retrieved thirty-two articles on the accuracy of most commonly used imaging modalities for pre-procedural assessment of the left atrial appendage morphology, namely, two-dimensional transesophageal echocardiography, three-dimensional transesophageal echocardiography, computed tomography, and three-dimensional printing. There is strong evidence that real-time three-dimensional transesophageal echocardiography is more accurate than two-dimensional transesophageal echocardiography. Three-dimensional computed tomography has recently emerged as an imaging modality and it showed exceptional accuracy when merged with three-dimensional printing technology. However, real time three-dimensional transesophageal echocardiography may be considered the preferred imaging modality as it can provide accurate measurements without requiring radiation exposure or contrast administration. We will present the most common imaging modality used for LAA assessment and will provide an algorithmic approach including preprocedural, periprocedural, intraprocedural, and postprocedural.

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A novel range telescope concept for proton CT

Physics in Medicine and Biology ◽

10.1088/1361-6560/ac4b39 ◽

2022 ◽

Author(s):

Marc Granado-González ◽

César Jesús-Valls ◽

Thorsten Lux ◽

Tony Price ◽

Federico Sánchez

Keyword(s):

Computed Tomography ◽

Proton Beam ◽

Energy Resolution ◽

Plastic Scintillator ◽

Proton Beam Therapy ◽

Stopping Power ◽

High Quality ◽

X Ray ◽

Proton Computed Tomography ◽

Clinical Conditions

Abstract Proton beam therapy can potentially offer improved treatment for cancers of the head and neck and in paediatric patients. There has been asharp uptake of proton beam therapy in recent years as improved delivery techniques and patient benefits are observed. However, treatments are currently planned using conventional x-ray CT images due to the absence of devices able to perform high quality proton computed tomography(pCT) under realistic clinical conditions. A new plastic-scintillator-based range telescope concept, named ASTRA, is proposed here to measure the proton’s energy loss in a pCT system. Simulations conducted using GEANT4 yield an expected energy resolution of 0.7%. If calorimetric information is used the energy resolution could be further improved to about 0.5%. In addition, the ability of ASTRA to track multiple protons simultaneously is presented. Due to its fast components, ASTRA is expected to reach unprecedented data collection rates, similar to 10^8 protons/s.The performance of ASTRA has also been tested by simulating the imaging of phantoms. The results show excellent image contrast and relative stopping power reconstruction.

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Proton radiography and proton computed tomography based on time-resolved dose measurements

Physics in Medicine and Biology ◽

10.1088/0031-9155/58/22/8215 ◽

2013 ◽

Vol 58 (22) ◽

pp. 8215-8233 ◽

Cited By ~ 47

Author(s):

Mauro Testa ◽

Joost M Verburg ◽

Mark Rose ◽

Chul Hee Min ◽

Shikui Tang ◽

...

Keyword(s):

Computed Tomography ◽

Proton Radiography ◽

Time Resolved ◽

Proton Computed Tomography ◽

Dose Measurements

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Comparison of Ultrasonography with other Imaging Modalities for Detection of Adnexal Torosion: A Systematic Review

10.53350/pjmhs2115112840 ◽

2021 ◽

Vol 15 (11) ◽

pp. 2840-2842

Author(s):

Kiran Shakeel ◽

Syeda Khadija-Tul-Sughra Murrium ◽

Maria Yaseen ◽

Alia Iqbal ◽

Sara Yaseen ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Computed Tomography ◽

Magnetic Resonance ◽

Imaging Modality ◽

Meta Analysis ◽

Imaging Modalities ◽

Test Accuracy ◽

Index Test ◽

Adnexal Torsion ◽

Resonance Imaging

Background: Adnexal Torsion (AT), serious emergency of gynecology, frequently shows among nonspecific signs prominent to late analysis. Aim: To compare the test accuracy of Ultrasound, Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) for diagnosis of adnexal torsion. Methodology: We observed google scholar as well as Radiographics key till Dec 2019. Assortment standards studies report upon Imaging Modality accuracy (index test) within paediatric and adult females alleged of adnexal torsion matched by clinical analysis or usual clinical or radiological follow up duration till symptoms firmness (reference standard). Results: We mark off 3836 references, comprised 18 Studies (1654 females, 665-cases), as well as comprised 15 into meta analyses, ultrasound pooled-sensitivity (n =12, 1187 females) was 0.79 (95% CI= 0.63 to 0.92) as well as specificity was 0.76 (95% CI= 0.54 to 0.93), by means of positive as well as negative probability fractions 4.35 (95% CI= 2.03 to 9.32) and 0.29 (95% CI= 0.13 to 0.66), correspondingly. By Doppler Ultrasound (n=7, 845 females) produced alike and specificity (0.88, 95% CI= 0.72 to 1.00) and sensitivity (0.80, 95% CI= 0.67 to 0.93). For magnetic resonance imaging (n=3, 99 females), pooled-sensitivity was 0.81 (95% CI=0.63 to 0.91) as well as specificity was 0.91 (95% CI= 0.80 to 0.96). Meta-analysis for Computed Tomography was impossible by 2 case control-studies as well as one cohort-study (n=3, 232 females). Its range of sensitivity was 0.74 to 0.95 as well as specificity 0.80 to 0.90. Conclusions: As a first line analytic examination for alleged AT, ultrasound has good performance. Increment in quantity of AT cases needs precise, rapid, as well as correct analytic extent. It has been utmost popular method as allied with further Imaging Modalities. MRI might compromise better specificity for investigating intricate morphology of ovary, nonetheless further proof is wanted. Beside with medical doubt as well as approximations. This study will offer sufficient appreciated evidence to understand sonographic markers impact during OT analysis precisely. Keywords: Adnexa, Computed Tomography, Doppler, Magnetic Resonance Imaging, Meta-analysis, Ovary, Test Accuracy,

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Proton Radiography and Proton Computed Tomography

Radiation Therapy Dosimetry: A Practical Handbook ◽

10.1201/9781351005388-29 ◽

2021 ◽

pp. 457-464

Author(s):

Xinyuan Chen ◽

Tianyu Zhao

Keyword(s):

Computed Tomography ◽

Proton Radiography ◽

Proton Computed Tomography

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Comparative Assessment of Midfoot Osteoarthritis Diagnostic Sensitivity Using Weightbearing Computed Tomography vs Weightbearing Radiography

Foot & Ankle Orthopaedics ◽

10.1177/2473011420s00457 ◽

2020 ◽

Vol 5 (4) ◽

pp. 2473011420S0045

Author(s):

Jesse Steadman ◽

Yantarat Sripanich ◽

Chamnanni Rungprai ◽

Charles L. Saltzman ◽

Alexej Barg

Keyword(s):

Computed Tomography ◽

Imaging Modality ◽

Treatment Options ◽

Correct Diagnosis ◽

Diagnostic Sensitivity ◽

Imaging Modalities ◽

Complication Rates ◽

Lisfranc Joint ◽

Significant Discrepancy ◽

Joint Group

Category: Midfoot/Forefoot; Other Introduction/Purpose: Osteoarthritis (OA) of the midfoot can elicit significant pain, disability, and decreased quality of life in affected patients. Therefore, correct diagnosis and appropriate, timely interventions towards this degeneration is essential. Currently, weightbearing radiography (WBR) has been widely accepted as the standard method in assessing midfoot OA. However, the complex structural anatomy of this region poses unique challenges in its visualization due to the obscurance caused by the overlapping osseous structures present when observed in a two-dimensional perspective. Weightbearing computed tomography (WBCT), providing a relatively clearer visualization of the midfoot could also be used for evaluation. This study aims to perform a single center, retrospective, intra-patient analysis identifying the discrepancy in midfoot OA diagnostic sensitivity among the two imaging modalities (WBCT vs. WBR). Methods: After gaining approval from an internal review board, a retrospective analysis of patient electronic health records was performed to assess the discrepancy of midfoot OA diagnostic sensitivity among WBCT and WBR. The radiological interpretation (RI) of 761 consecutive patient WBCT images were systematically assessed for OA diagnosed in 3 midfoot joint groups (Chopart group; 2 joints, midfoot group; 6 joints, Lisfranc group; 5 joints). A case was considered positive for OA if the WBCT RI contained any explicit mention of midfoot OA or any reported signs of the pathology including mild, moderate, or severe degeneration, joint space narrowing, osteophytic changes, spurring, cystic changes, or sclerosis in at least one of the aforementioned joint groups. After an appropriate washout period, the observer then synonymously reviewed the WBR RI of each positive OA case. A sensitivity metric was calculated for the OA incidence and severity discrepancy between the two imaging modalities. Results: A total of 302 (mean age, 56.0 +- 16.0 years; 140 left and 162 right) feet were assessed in this study. 244 cases of Chopart OA were detected on WBCT RI, where only 184 cases were detected on the WBR RI of the same feet, resulting in a diagnostic discrepancy of 24.6%. In the midfoot joint group, WBCT RI and WBR RI detected 96 and 67 cases of OA respectively, yielding a 30.2% discrepancy. Finally, in the Lisfranc joint group, the WBCT and WBR RI detected 174 and 129 cases of OA, respectively, showing a 25.9% discrepancy in diagnosis. Additionally, the OA severity was downgraded between modalities in 7.0%, 4.2%, and 8.0% for the Chopart, midfoot, and Lisfranc joint groups, respectively. Conclusion: After assessing 244 Chopart, 96 midfoot, and 174 Lisfranc cases of OA detected by WBCT, a significant discrepancy has been observed in the diagnostic abilities of midfoot OA among the two imaging modalities studied. With this difference realized, in addition to the recent higher availability, decreasing cost, and low radiation exposure offered by WBCT, this imaging modality may have the ability to aid physicians considerably in their clinical practice. Detecting and correctly diagnosing the severity of this pathology may lead to more appropriate treatment options, lower complication rates, and better patient outcomes.

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Imaging Modalities for Evaluation of Intestinal Obstruction

Clinics in Colon and Rectal Surgery ◽

10.1055/s-0041-1729737 ◽

2021 ◽

Author(s):

David W. Nelms ◽

Brian R. Kann

Keyword(s):

Magnetic Resonance Imaging ◽

Computed Tomography ◽

Magnetic Resonance ◽

Imaging Modality ◽

Methodological Approach ◽

Imaging Modalities ◽

Resonance Imaging ◽

Rectal Surgeon ◽

Contrast Imaging ◽

Plain Radiographs

AbstractIt is essential for the colon and rectal surgeon to understand the evaluation and management of patients with both small and large bowel obstructions. Computed tomography is usually the most appropriate and accurate diagnostic imaging modality for most suspected bowel obstructions. Additional commonly used imaging modalities include plain radiographs and contrast imaging/fluoroscopy, while less commonly utilized imaging modalities include ultrasonography and magnetic resonance imaging. Regardless of the imaging modality used, interpretation of imaging should involve a systematic, methodological approach to ensure diagnostic accuracy.

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Role of multidetector computed tomography in evaluation of retroperitoneal masses

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20184888 ◽

2018 ◽

Vol 6 (12) ◽

pp. 3949

Author(s):

Diksha Chinwan ◽

Poonam Vohra

Keyword(s):

Computed Tomography ◽

Multidetector Computed Tomography ◽

Imaging Modality ◽

Plain Radiograph ◽

Imaging Modalities ◽

Cross Sectional ◽

Multiplanar Reconstructions ◽

Abdominal Masses ◽

Mixed Pattern ◽

The Masses

Background: Diagnostic imaging plays an important role in the evaluation of abdominal masses. Many imaging modalities are available ranging from conventional modalities to the cross-sectional modalities like USG, CT and MRI. The main principles of imaging are to determine the origin of mass, its measurement, extent, characterisation and assessment of its effect on contiguous organs. In the past, the mainstay was conventional imaging modalities like plain radiograph, Gastrointestinal contrast studies and I.V.U. Modern imaging modalities allow an early and accurate pre-operative diagnosis resulting in a higher rate of surgical resection and improvement of survival.Methods: A Cross-sectional observational study was done in 30 patients. Patients of either sex of any age group who had presented with involvement of retroperitoneal organs detected by routine ultrasound and postoperative patients with recurrence were included in our study.Results: Ultrasound is the initial imaging modality of choice since it is inexpensive, easy to perform and no radiation exposure. On USG, the retroperitoneal masses are classified as solid or cystic or mixed. Since most of the retroperitoneal masses have hetroechoic/mixed pattern, they cannot be characterized by ultrasound alone and hence need further evaluation.Conclusions: Multidetector computed tomography is the imaging modality of choice for further evaluation and characterization. CT protocol for evaluation of the retroperitoneum consisted of both non-enhanced and contrast-enhanced scans for localisation and characterisation of the masses. Multiplanar reconstructions allowed the images to be viewed in any plane chosen including a curved plane thus helping in defining the exact location and extent of the lesion. With MIP and volume rendered images, the relationship of the vessels with the mass lesions was clearly visualized.

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