Pub Date : 2023-09-07DOI: 10.31487/j.rdi.2023.01.01
Mudasir Ashraf Shah, S. M. Danish Qaseem, Md Ahmad, Saifullah Khalid, Shagufta Wahab, Sajad Ahmad Rather, S. Y. Masood
Purpose: The AAPM Task Group (TG) reports 204 and 220 presented methods for evaluation of patient dose by announcing the SSDE. The TG reports provide the Size Specific Conversion factors that can be multiplied to CTDIvol to calculate the patient dose in terms of SSDE constructed from Deff (AAPM TG-204) and Dw (AAPM TG-220). Our study presents a comparison of the two TG reports on SSDE for the routine Abdominal Computed Tomography. Materials and Methods: The scan lengths of abdomen were measured from computed tomography (CT) topographic images and cross-section at the mid-slice of the abdomen were measured from tomographic images of 61 adults who had undergone abdominal CT using the GE Advance Workstation (AWS) software. The Deff and Dw was computed according to TG- 204 and TG-220 reports, respectively. Further, we performed the correlation analysis between Deff and BMI, Dw and BMI and SSDE and BMI for both the TG- reports. The Student’s paired t-test was performed to compare the two of SSDE calculation methods. Results: The results confirm that the mean value of SSDE is 13.04 (𝑚𝐺𝑦) and 13.60 (𝑚𝐺𝑦) for AAPM TG-220 and AAPM TG-204, respectively. And a good positive correlation was observed between Deff and BMI, Dw and BMI with r = 0.67 and r = 0.68 respectively. Also, the weak correlation was observed between SSDE and BMI for both the TG - reports. The Student’s paired t-test shows that the two means of SSDE calculation methods are significantly different (𝑝< 0.01) in abdominal computed tomography. Conclusion: We confirm the AAPM TG reports 204/220 using clinical data for SSDE calculation that the mean SSDE values computed from Deff and Dw in abdomenal computed tomography are significantly different and we conclude that the SSDE calculated by Dw method gives a more accurate evaluation of SSDE for the patients undergoing abdominal computed tomography scan then the SSDE calculated by Deff method.
{"title":"Size Specific Dose Estimate in Abdominal Computed Tomography by AAPM TG Report-204 and AAPM TG Report-220","authors":"Mudasir Ashraf Shah, S. M. Danish Qaseem, Md Ahmad, Saifullah Khalid, Shagufta Wahab, Sajad Ahmad Rather, S. Y. Masood","doi":"10.31487/j.rdi.2023.01.01","DOIUrl":"https://doi.org/10.31487/j.rdi.2023.01.01","url":null,"abstract":"Purpose: The AAPM Task Group (TG) reports 204 and 220 presented methods for evaluation of patient dose by announcing the SSDE. The TG reports provide the Size Specific Conversion factors that can be multiplied to CTDIvol to calculate the patient dose in terms of SSDE constructed from Deff (AAPM TG-204) and Dw (AAPM TG-220). Our study presents a comparison of the two TG reports on SSDE for the routine Abdominal Computed Tomography. \u0000Materials and Methods: The scan lengths of abdomen were measured from computed tomography (CT) topographic images and cross-section at the mid-slice of the abdomen were measured from tomographic images of 61 adults who had undergone abdominal CT using the GE Advance Workstation (AWS) software. The Deff and Dw was computed according to TG- 204 and TG-220 reports, respectively. Further, we performed the correlation analysis between Deff and BMI, Dw and BMI and SSDE and BMI for both the TG- reports. The Student’s paired t-test was performed to compare the two of SSDE calculation methods. \u0000Results: The results confirm that the mean value of SSDE is 13.04 (𝑚𝐺𝑦) and 13.60 (𝑚𝐺𝑦) for AAPM TG-220 and AAPM TG-204, respectively. And a good positive correlation was observed between Deff and BMI, Dw and BMI with r = 0.67 and r = 0.68 respectively. Also, the weak correlation was observed between SSDE and BMI for both the TG - reports. The Student’s paired t-test shows that the two means of SSDE calculation methods are significantly different (𝑝< 0.01) in abdominal computed tomography. \u0000Conclusion: We confirm the AAPM TG reports 204/220 using clinical data for SSDE calculation that the mean SSDE values computed from Deff and Dw in abdomenal computed tomography are significantly different and we conclude that the SSDE calculated by Dw method gives a more accurate evaluation of SSDE for the patients undergoing abdominal computed tomography scan then the SSDE calculated by Deff method.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122412121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-03-11DOI: 10.31487/j.rdi.2022.01.01
Tokiko Nakamura, H. Kato, Shoichi Suzuki, Sachila Niroshani, I. Kobayashi, Kyoichi Kato, T. Negishi, Ryusuke Irie
Estimating the average glandular dose (AGD) from a mammographic exam is essential for assessing radiation-induced cancer risk. In this study, we propose Mdec-Toki Monte Carlo Method with the aim of visualizing the dose distribution of the entire breast under different arbitrary glandularities, compressed thicknesses, and exposure parameters and evaluating the absorbed dose at an arbitrary point. A phantom with 50% glandularity values was used for the optically stimulated luminescence (OSL) dosimeters measurements to obtain the percentage depth dose PDD from the incident surface to the emission surface. Using the Mdec-Toki method under the same settings as those used for actual measurements and PDD was used to calculate the AGD. The PDD and AGD at an arbitrary point, obtained from Mdec-Toki method simulations and the actual measurements using OSL were similar. The proposed method may be adapted to individual patients and can support radiation safety management during mammography.
{"title":"A Potential Solution to Assess the Absorbed Dose at Any Point in Breast During Digital Breast Tomosynthesis (DBT) Imaging Using a Novel Monte Carlo Simulation Software","authors":"Tokiko Nakamura, H. Kato, Shoichi Suzuki, Sachila Niroshani, I. Kobayashi, Kyoichi Kato, T. Negishi, Ryusuke Irie","doi":"10.31487/j.rdi.2022.01.01","DOIUrl":"https://doi.org/10.31487/j.rdi.2022.01.01","url":null,"abstract":"Estimating the average glandular dose (AGD) from a mammographic exam is essential for assessing radiation-induced cancer risk. In this study, we propose Mdec-Toki Monte Carlo Method with the aim of visualizing the dose distribution of the entire breast under different arbitrary glandularities, compressed thicknesses, and exposure parameters and evaluating the absorbed dose at an arbitrary point. A phantom with 50% glandularity values was used for the optically stimulated luminescence (OSL) dosimeters measurements to obtain the percentage depth dose PDD from the incident surface to the emission surface. Using the Mdec-Toki method under the same settings as those used for actual measurements and PDD was used to calculate the AGD. The PDD and AGD at an arbitrary point, obtained from Mdec-Toki method simulations and the actual measurements using OSL were similar. The proposed method may be adapted to individual patients and can support radiation safety management during mammography.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130029805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-21DOI: 10.31487/j.rdi.2021.02.01
Sachila Niroshani, Tokiko Nakamura, N. Michiru, T. Negishi
Purpose: To assess the iodine enhancement intensity of breast lesions in low energy (LE) images obtained in contrast-enhanced spectral mammography (CESM) with different tissue compositions. Materials and Methods: A 50 mm dedicated phantom with different lesion insert and iodine insert were used to assess the enhancement intensity quantitatively. The target slab of the phantom consists of three lesions + iodine inserts together and 100% adipose equivalent,100% glandular equivalent inserts alone to mimic the adipose and glandular lesion without contrast-enhancement. Each iodine inserts having a concentration of 0.5 mgI/cm3, 1.0 mgI/cm3, 2.0 mgI/cm3. The phantom was exposed under semiautomated function at 28 kV, 30 kV, and 32 kV with Mo/Rh target/filter combination. Iodine intensity was estimated for three types of lesions at three breast equivalent compositions. Results: Lesions with fatty tissue had high intensity while lesions with glandular tissues had the minimum intensity. Among fatty lesions, highest mean intensity value (0.972±0.003) observed with minimum iodine concentration (F + 0.5 mgI/cm3). The highest mean intensity value (0.882±0.001) was found related to the glandular lesion with maximum iodine concentration (G + 2.0 mgI/cm3). The one-way ANOVA statistical test confirmed that mean intensity values were significantly varied among different lesions (P < 0.05). Conclusion: LE images obtained in CESM can be used to identify the different types of lesions without performing the full field digital mammography (FFDM) as an additional examination prior to the CESM procedure.
{"title":"Quantitative Assessment of Iodine Intensity of Different Types of Lesions in the Low-Energy (LE) Images of Contrast-Enhanced Spectral Mammography (CESM)","authors":"Sachila Niroshani, Tokiko Nakamura, N. Michiru, T. Negishi","doi":"10.31487/j.rdi.2021.02.01","DOIUrl":"https://doi.org/10.31487/j.rdi.2021.02.01","url":null,"abstract":"Purpose: To assess the iodine enhancement intensity of breast lesions in low energy (LE) images obtained in contrast-enhanced spectral mammography (CESM) with different tissue compositions.\u0000Materials and Methods: A 50 mm dedicated phantom with different lesion insert and iodine insert were used to assess the enhancement intensity quantitatively. The target slab of the phantom consists of three lesions + iodine inserts together and 100% adipose equivalent,100% glandular equivalent inserts alone to mimic the adipose and glandular lesion without contrast-enhancement. Each iodine inserts having a concentration of 0.5 mgI/cm3, 1.0 mgI/cm3, 2.0 mgI/cm3. The phantom was exposed under semiautomated function at 28 kV, 30 kV, and 32 kV with Mo/Rh target/filter combination. Iodine intensity was estimated for three types of lesions at three breast equivalent compositions.\u0000Results: Lesions with fatty tissue had high intensity while lesions with glandular tissues had the minimum intensity. Among fatty lesions, highest mean intensity value (0.972±0.003) observed with minimum iodine concentration (F + 0.5 mgI/cm3). The highest mean intensity value (0.882±0.001) was found related to the glandular lesion with maximum iodine concentration (G + 2.0 mgI/cm3). The one-way ANOVA statistical test confirmed that mean intensity values were significantly varied among different lesions (P < 0.05).\u0000Conclusion: LE images obtained in CESM can be used to identify the different types of lesions without performing the full field digital mammography (FFDM) as an additional examination prior to the CESM procedure.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121683505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-30DOI: 10.31487/j.rdi.2021.01.02
Aliya Ishaq, Sameera Naureen, Yasir M. Amin, Muhammad jamshaid Khan, A. Latif, S. Anwar, E. Ghazi
Introduction: Appendectomy is the most common surgical emergency and negative appendectomy is a one of recognized consequence of appendectomy. Recently an increased use of radiology is seen in diagnosing appendicitis and it has significantly decreased the rate of negative appendectomy. Every effort should be made to establish an exact diagnosis. If, however, this is impossible and a suspicion of appendicitis exists, exploration is mandatory. It is far better to subject a moderate number of patients to a theoretically unnecessary operation than to let one patient suffer perforation. Aim: Recently we have seen an increased use of radiology in our department for diagnosing appendicitis. The idea of conducting this audit was to calculate our negative appendectomy rate by correlating it with use of radiology and to compare it with international figures and to set up guidelines for use of radiology in diagnosing appendicitis on basis of results of our audit. Methods: Records of all patients who underwent appendectomy in Dubai Hospital, UAE from Jan 2018 to Jan 2019 were retrospectively analysed using electronic record system. Clinical diagnosis and radiological findings were compared with histopathology as gold standard for negative appendectomy rate. The sensitivity and specificity of different radiological procedures was calculated as well. Results: Total 165 patients underwent appendectomy in specified duration. Overall negative appendectomy rate was 17% with male being 9.7% and female rate 31%. CT scan was found to be 100% specific and 91.4% sensitive in diagnosing appendicitis while clinical diagnosis was accurate in 88.5% cases.
{"title":"Radiological Correlation of Negative Appendectomies: A Clinical Audit","authors":"Aliya Ishaq, Sameera Naureen, Yasir M. Amin, Muhammad jamshaid Khan, A. Latif, S. Anwar, E. Ghazi","doi":"10.31487/j.rdi.2021.01.02","DOIUrl":"https://doi.org/10.31487/j.rdi.2021.01.02","url":null,"abstract":"Introduction: Appendectomy is the most common surgical emergency and negative appendectomy is a one of recognized consequence of appendectomy. Recently an increased use of radiology is seen in diagnosing appendicitis and it has significantly decreased the rate of negative appendectomy. Every effort should be made to establish an exact diagnosis. If, however, this is impossible and a suspicion of appendicitis exists, exploration is mandatory. It is far better to subject a moderate number of patients to a theoretically unnecessary operation than to let one patient suffer perforation.\u0000Aim: Recently we have seen an increased use of radiology in our department for diagnosing appendicitis. The idea of conducting this audit was to calculate our negative appendectomy rate by correlating it with use of radiology and to compare it with international figures and to set up guidelines for use of radiology in diagnosing appendicitis on basis of results of our audit.\u0000Methods: Records of all patients who underwent appendectomy in Dubai Hospital, UAE from Jan 2018 to Jan 2019 were retrospectively analysed using electronic record system. Clinical diagnosis and radiological findings were compared with histopathology as gold standard for negative appendectomy rate. The sensitivity and specificity of different radiological procedures was calculated as well.\u0000Results: Total 165 patients underwent appendectomy in specified duration. Overall negative appendectomy rate was 17% with male being 9.7% and female rate 31%. CT scan was found to be 100% specific and 91.4% sensitive in diagnosing appendicitis while clinical diagnosis was accurate in 88.5% cases.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134528110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-28DOI: 10.31487/j.rdi.2020.04.03
R. Vennila, P. Venkatraman
In 21st century, the year 2020 was expected with much development in India as well many other countries. But unfortunately, the world is facing many natural calamities. World is taking steps towards rescue mission of the disasters. Among of those calamities, deadly Corona Virus remains still all over the world as pandemic disease. Even the developed countries are struggling to come back to its normal routine. India is a country with developing technologies. Vaccines are yet to be developed for treatment of this Novel Corona Virus. As a diagnostic tool, Nasopharyngeal and Oropharyngeal swabs are taken from the person and tested using RT-PCR. This test is not 100 percent accurate. Confirmed COVID patients after few days are undergoing the medical imaging. This diagnostic imaging technique helps in showing the progression of this virus spread in Upper and Lower respiratory system. Chest Radiography is low cost modality but its sensitivity towards observation is 69%. Lung Ultrasound is used in Intensive Care patients and not used for routine diagnosing purpose. Computed Tomography plays a crucial role in three-dimensional chest imaging of COVID-19 patients. The sensitivity of CT is 98%. The aim of this paper is to consider CT as a tool for diagnosing COVID-19 patient than using the standard tool RT-PCR. A brief knowledge about imaging modality like X-ray, Ultrasound and Computed Tomography when used against COVID patient is explained. This paper gives reason for the ideal use of CT diagnosis for COVID 19.
{"title":"A Short Review of Benefits of Using Chest CT Characteristics for Early diagnoses to Corona Virus Disease 2019 (COVID-19)","authors":"R. Vennila, P. Venkatraman","doi":"10.31487/j.rdi.2020.04.03","DOIUrl":"https://doi.org/10.31487/j.rdi.2020.04.03","url":null,"abstract":"In 21st century, the year 2020 was expected with much development in India as well many other countries.\u0000But unfortunately, the world is facing many natural calamities. World is taking steps towards rescue mission\u0000of the disasters. Among of those calamities, deadly Corona Virus remains still all over the world as pandemic\u0000disease. Even the developed countries are struggling to come back to its normal routine. India is a country\u0000with developing technologies. Vaccines are yet to be developed for treatment of this Novel Corona Virus.\u0000As a diagnostic tool, Nasopharyngeal and Oropharyngeal swabs are taken from the person and tested using\u0000RT-PCR. This test is not 100 percent accurate. Confirmed COVID patients after few days are undergoing\u0000the medical imaging. This diagnostic imaging technique helps in showing the progression of this virus\u0000spread in Upper and Lower respiratory system. Chest Radiography is low cost modality but its sensitivity\u0000towards observation is 69%. Lung Ultrasound is used in Intensive Care patients and not used for routine\u0000diagnosing purpose. Computed Tomography plays a crucial role in three-dimensional chest imaging of\u0000COVID-19 patients. The sensitivity of CT is 98%. The aim of this paper is to consider CT as a tool for\u0000diagnosing COVID-19 patient than using the standard tool RT-PCR. A brief knowledge about imaging\u0000modality like X-ray, Ultrasound and Computed Tomography when used against COVID patient is\u0000explained. This paper gives reason for the ideal use of CT diagnosis for COVID 19.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116732131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-23DOI: 10.31487/j.rdi.2020.02.08
K. Kulkarni
Radioiodine is often seen to accumulate within breast tissue in patients with differentiated thyroid cancer. Although the risk of secondary breast malignancy in patients with differentiated thyroid cancer treated with radioiodine is controversial, the identification and reduction of this uptake is prudent to minimize the radiation absorbed dose to the breast tissue. This article reviews the literature describing the etiology, frequency and patterns of radioiodine uptake in breast tissue. Approaches and techniques to help minimize the radioiodine uptake in lactating and nonlactating breasts are presented.
{"title":"Breast Uptake of Radio-iodine in Differentiated Thyroid Cancer","authors":"K. Kulkarni","doi":"10.31487/j.rdi.2020.02.08","DOIUrl":"https://doi.org/10.31487/j.rdi.2020.02.08","url":null,"abstract":"Radioiodine is often seen to accumulate within breast tissue in patients with differentiated thyroid cancer.\u0000Although the risk of secondary breast malignancy in patients with differentiated thyroid cancer treated with\u0000radioiodine is controversial, the identification and reduction of this uptake is prudent to minimize the\u0000radiation absorbed dose to the breast tissue. This article reviews the literature describing the etiology,\u0000frequency and patterns of radioiodine uptake in breast tissue. Approaches and techniques to help minimize\u0000the radioiodine uptake in lactating and nonlactating breasts are presented.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128640817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-07DOI: 10.31487/J.RDI.2020.02.01
A. Prem, Dongmei Cui, Edgar R Meyer, Gongchao Yang, Jian Chen, Rachel Crim
Trigeminal ganglion injection is a common procedure for many facial pain syndromes, including trigeminal neuralgia. The procedure is usually done under fluoroscopy guidance to target at the foramen ovale where lies the trigeminal ganglion and the mandibular branch of trigeminal nerve exits. In this project, Amira® software was used to create 3D structures that can be visualized stereoscopically and involve the structures to study the procedure pathway. The detailed anatomical structures include the skin, skull, external and internal pterygoid muscle, masseter muscle, buccinator muscle, external carotidartery and its branches, internal carotid artery and its branches, vertebral artery, trigeminal ganglion and its branches, internal jugular vein, and parotid gland were created. The structures’ relationships and potential complications are described. The 3D model is used to guide and educate students about safe procedure pathways and may potentially be used to evaluate and modify procedures scientifically.
{"title":"Identification of the Preferred Interventional Approach to Trigeminal Ganglion Using Three-Dimensional Reconstruction Stereoscopic Model","authors":"A. Prem, Dongmei Cui, Edgar R Meyer, Gongchao Yang, Jian Chen, Rachel Crim","doi":"10.31487/J.RDI.2020.02.01","DOIUrl":"https://doi.org/10.31487/J.RDI.2020.02.01","url":null,"abstract":"Trigeminal ganglion injection is a common procedure for many facial pain syndromes, including trigeminal\u0000neuralgia. The procedure is usually done under fluoroscopy guidance to target at the foramen ovale where\u0000lies the trigeminal ganglion and the mandibular branch of trigeminal nerve exits. In this project, Amira®\u0000software was used to create 3D structures that can be visualized stereoscopically and involve the structures\u0000to study the procedure pathway. The detailed anatomical structures include the skin, skull, external and\u0000internal pterygoid muscle, masseter muscle, buccinator muscle, external carotidartery and its branches,\u0000internal carotid artery and its branches, vertebral artery, trigeminal ganglion and its branches, internal\u0000jugular vein, and parotid gland were created. The structures’ relationships and potential complications are\u0000described. The 3D model is used to guide and educate students about safe procedure pathways and may\u0000potentially be used to evaluate and modify procedures scientifically.\u0000","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130672007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-01-21DOI: 10.31487/j.rdi.2019.04.06
Akihiko Takahashi, K. Himuro, K. Funada, M. Sasaki, S. Baba
Aim: The purpose of this study was to assess the impact of the collimator in viewing the dopamine transporter, using 123I ioflupane single-photon emission computed tomography (DaT-SPECT) images utilizing a Monte Carlo simulation. Methods: For the purpose of this study, the Monte Carlo simulation of electrons and photons (MCEP)- SPECT was used. A numerical phantom was created from a real basal ganglia phantom and installed within the code. The specific binding ratios (SBRs) were 5.03 and 2.01 for the background concentration of 7.44 kBq/mL or 7.04 and 3.03 for a background concentration of 5.56 kBq/mL. The simulated images were evaluated using a recovery coefficient (RC). Initially, we simulated the performance of 14 collimators without resolution correction to investigate the impact of the collimator dimension. The effects of two resolution correction methods (collimator broad correction (CBC) and three-dimensional frequency– distance relationship (3D-FDR)) on two reconstruction methods (Ordered-Subsets Expectation Maximization (OSEM) and Filtered back projection (FBP)) was assessed for collimators that demonstrated a better RC value. Results: Five low-energy high-resolution (LEHR) collimators and one medium-energy general-purpose (MEGP) collimator demonstrated superior RC values. These collimators had a high aspect ratio (holelength/hole-diameter). The maximum RC value without resolution correction was 64.9% when the image was reconstructed with OSEM. The RC value improved to 79.7% when the resolution correction of CBC was applied. When the resolution collection was applied, the RCs improved by approximately 1.2 times when compared against those without the resolution correction. In terms of the reconstruction method, the RC obtained using OSEM was statistically insignificant when compared to the RC using FBP. The difference in the RC value with collimators decreased according to resolution correction. Conclusion: The LEHR collimator with a high aspect ratio, and the OSEM with spatial resolution correction were confirmed to be appropriate for DaT-SPECT imaging. In terms of the reconstruction method, CBC was more favourable than FDR.
目的:本研究的目的是利用蒙特卡罗模拟的123I碘氟烷单光子发射计算机断层扫描(pat - spect)图像，评估准直仪对观察多巴胺转运体的影响。方法:采用Monte Carlo simulation of electron and photon (MCEP)-SPECT进行研究。从真实的基底神经节幻像中创建了一个数值幻像，并将其安装在代码中。背景浓度为7.44kBq/mL时，特异性结合比分别为5.03和2.01，背景浓度为5.56 kBq/mL时，特异性结合比分别为7.04和3.03。利用恢复系数(RC)对模拟图像进行评价。首先，我们模拟了14个没有分辨率校正的准直器的性能，以研究准直器尺寸的影响。研究了两种分辨率校正方法(准直器宽校正(CBC)和三维频率-距离关系(3D-FDR))对两种重建方法(有序子集期望最大化(OSEM)和滤波后投影(FBP))的影响，并对具有较好RC值的准直器进行了评估。结果:5个低能量高分辨率(LEHR)准直器和1个中等能量通用型(MEGP)准直器显示出优越的RC值。这些准直器具有很高的纵横比(孔长/孔直径)。在不进行分辨率校正的情况下，用OSEM重建图像的最大RC值为64.9%。采用cbc分辨率校正后，RC值提高到79.7%。当应用分辨率收集时，与没有分辨率校正的RCs相比，RCs提高了约1.2倍。在重建方法方面，与使用FBP的RC相比，使用OSEM获得的theRC在统计学上不显著。随着分辨率的修正，准直器的RC值差异减小。结论:高宽高比的LEHR准直器和空间分辨率校正的OSEM适合于pet - spect成像。在重建方法上，cbc优于FDR。
{"title":"Impact of Collimator on DaT-SPECT Imaging: Monte Carlo Simulation Study","authors":"Akihiko Takahashi, K. Himuro, K. Funada, M. Sasaki, S. Baba","doi":"10.31487/j.rdi.2019.04.06","DOIUrl":"https://doi.org/10.31487/j.rdi.2019.04.06","url":null,"abstract":"Aim: The purpose of this study was to assess the impact of the collimator in viewing the dopamine\u0000transporter, using 123I ioflupane single-photon emission computed tomography (DaT-SPECT) images\u0000utilizing a Monte Carlo simulation.\u0000Methods: For the purpose of this study, the Monte Carlo simulation of electrons and photons (MCEP)-\u0000SPECT was used. A numerical phantom was created from a real basal ganglia phantom and installed within\u0000the code. The specific binding ratios (SBRs) were 5.03 and 2.01 for the background concentration of 7.44\u0000kBq/mL or 7.04 and 3.03 for a background concentration of 5.56 kBq/mL. The simulated images were\u0000evaluated using a recovery coefficient (RC). Initially, we simulated the performance of 14 collimators\u0000without resolution correction to investigate the impact of the collimator dimension. The effects of two\u0000resolution correction methods (collimator broad correction (CBC) and three-dimensional frequency–\u0000distance relationship (3D-FDR)) on two reconstruction methods (Ordered-Subsets Expectation\u0000Maximization (OSEM) and Filtered back projection (FBP)) was assessed for collimators that demonstrated\u0000a better RC value.\u0000Results: Five low-energy high-resolution (LEHR) collimators and one medium-energy general-purpose\u0000(MEGP) collimator demonstrated superior RC values. These collimators had a high aspect ratio (holelength/hole-diameter). The maximum RC value without resolution correction was 64.9% when the image\u0000was reconstructed with OSEM. The RC value improved to 79.7% when the resolution correction of CBC\u0000was applied. When the resolution collection was applied, the RCs improved by approximately 1.2 times\u0000when compared against those without the resolution correction. In terms of the reconstruction method, the\u0000RC obtained using OSEM was statistically insignificant when compared to the RC using FBP. The\u0000difference in the RC value with collimators decreased according to resolution correction.\u0000Conclusion: The LEHR collimator with a high aspect ratio, and the OSEM with spatial resolution correction\u0000were confirmed to be appropriate for DaT-SPECT imaging. In terms of the reconstruction method, CBC\u0000was more favourable than FDR.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124832360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-16DOI: 10.31487/j.rdi.2019.04.01
D. Grönemeyer, B. Brandts, C. Lehrenfeld, Frauke Metz, M. Garmer, O. Klein-Wiele
Radiation dose from cardiac CT seems to be underestimated. To determine the effect of iterative reconstruction in coronary artery calcium (CAC) scoring on false positive lesions and radiation dose using a noise threshold. Noise-based thresholds have been previously suggested to reduce false positive lesions in lower dose protocols. In 388 matched pairs of patients we performed CAC scoring using a 320-row CT-scanner with standard dose filtered backprojection (FBP) and lower dose iterative reconstruction (IR). Dose modulation was based on a noise threshold. Radiation dose, image quality and extent of false-positive calcifications were obtained. IR versus FBP showed a reduced dose length product (median 61 versus 74; p< 0.001), less noise (median SD 14.71 versus 18.07; p< 0.001) and higher signal-to-noise ratio (median 4.01 versus 3.14; p< 0.001). Using IR in 388 patients, a low quantity of false-positive calcifications was found in 302 patients, a moderate quantity in 76 patients and a high quantity in 10 patients, while using FBP, the corresponding distribution of patients was 79, 175 and 134 (p<0.001). In this clinical setting we confirm the observation of a phantom study that CAC scoring using iterative reconstruction and a noise threshold is effective for the reduction of radiation dose.
心脏CT的辐射剂量似乎被低估了。利用噪声阈值确定冠状动脉钙(CAC)评分迭代重建对假阳性病变和辐射剂量的影响。基于噪声的阈值先前已被建议在低剂量方案中减少假阳性病变。在388对匹配的患者中，我们使用标准剂量过滤反向投影(FBP)和低剂量迭代重建(IR)的320排ct扫描仪进行CAC评分。剂量调制是基于噪声阈值。获得辐射剂量、图像质量和假阳性钙化程度。与FBP相比，IR显示剂量长度乘积减少(中位数61比74;p< 0.001)，噪声较小(SD中位数14.71 vs 18.07;P < 0.001)和更高的信噪比(中位数4.01 vs 3.14;p < 0.001)。在388例患者中，IR检出低量钙化302例，中等量76例，高量10例，而FBP检出相应的分布分别为79例、175例和134例(p<0.001)。在这个临床环境中，我们证实了一项幻影研究的观察结果，即使用迭代重建和噪声阈值的CAC评分对于降低辐射剂量是有效的。
{"title":"False-Positive Calcifications and Radiation Dose in Coronary Artery Calcium Scoring Using Iterative Reconstruction on The Basis of a Noise Threshold","authors":"D. Grönemeyer, B. Brandts, C. Lehrenfeld, Frauke Metz, M. Garmer, O. Klein-Wiele","doi":"10.31487/j.rdi.2019.04.01","DOIUrl":"https://doi.org/10.31487/j.rdi.2019.04.01","url":null,"abstract":"Radiation dose from cardiac CT seems to be underestimated. To determine the effect of iterative reconstruction in coronary artery calcium (CAC) scoring on false positive lesions and radiation dose using a noise threshold. Noise-based thresholds have been previously suggested to reduce false positive lesions in lower dose protocols. In 388 matched pairs of patients we performed CAC scoring using a 320-row CT-scanner with standard dose filtered backprojection (FBP) and lower dose iterative reconstruction (IR). Dose modulation was based on a noise threshold. Radiation dose, image quality and extent of false-positive calcifications were obtained. IR versus FBP showed a reduced dose length product (median 61 versus 74; p< 0.001), less noise (median SD 14.71 versus 18.07; p< 0.001) and higher signal-to-noise ratio (median 4.01 versus 3.14; p< 0.001). Using IR in 388 patients, a low quantity of false-positive calcifications was found in 302 patients, a moderate quantity in 76 patients and a high quantity in 10 patients, while using FBP, the corresponding distribution of patients was 79, 175 and 134 (p<0.001). In this clinical setting we confirm the observation of a phantom study that CAC scoring using iterative reconstruction and a noise threshold is effective for the reduction of radiation dose.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134118107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-09-30DOI: 10.31487/j.rdi.2019.03.09
C. Erasmus, L. V. Haaften, L. Engel-Hoek, M. Lagarde, M. V. Gerven, R. Admiraal
Treacher Collins syndrome (TCS) is a rare congenital disorder of craniofacial development affecting 1 in 50 000 live births. The spectrum of the clinical features is wide ranging from mild to severe anatomical deviances, affecting breathing, mastication, swallowing, facial expression, hearing and speech. The aim of this study was to describe the experienced feeding and swallowing problems and to study the related orofacial muscles in four patients with Treacher Collins Syndrome (TCS), in order to increase important knowledge concerning mastication and swallowing problems in children with TCS. Four children with TCS were evaluated with a clinical feeding and swallowing assessment. In addition, quantitative muscle ultrasound of orofacial muscles was performed. The mastication problems and dysphagia are due to a range of problems. Orofacial muscles were hypoplastic with a deviant structure influencing strength. We recommend a regularly assessment with special attention to mastication, intake and growth. Training (maintain chewing) and compensation (adequate intake) should be advised.
{"title":"Mastication Problems and Dysphagia In 4 Patients with Treacher Collins Syndrome Due to Affected Orofacial Muscles","authors":"C. Erasmus, L. V. Haaften, L. Engel-Hoek, M. Lagarde, M. V. Gerven, R. Admiraal","doi":"10.31487/j.rdi.2019.03.09","DOIUrl":"https://doi.org/10.31487/j.rdi.2019.03.09","url":null,"abstract":"Treacher Collins syndrome (TCS) is a rare congenital disorder of craniofacial development affecting 1 in 50 000 live births. The spectrum of the clinical features is wide ranging from mild to severe anatomical deviances, affecting breathing, mastication, swallowing, facial expression, hearing and speech. The aim of this study was to describe the experienced feeding and swallowing problems and to study the related orofacial muscles in four patients with Treacher Collins Syndrome (TCS), in order to increase important knowledge concerning mastication and swallowing problems in children with TCS.\u0000Four children with TCS were evaluated with a clinical feeding and swallowing assessment. In addition, quantitative muscle ultrasound of orofacial muscles was performed.\u0000The mastication problems and dysphagia are due to a range of problems. Orofacial muscles were hypoplastic with a deviant structure influencing strength. We recommend a regularly assessment with special attention to mastication, intake and growth. Training (maintain chewing) and compensation (adequate intake) should be advised.","PeriodicalId":308916,"journal":{"name":"Radiology and Medical Diagnostic Imaging","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126229068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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