Isovaleric acidemia is a very rare autosomal recessive inborn error of leucine metabolism caused by deficiency of the mitochondrial enzyme isovaleryl-coenzyme A dehydrogenase. The disease has two well-known clinical phenotypes: an acute neonatal presentation with severe metabolic crisis and a chronic intermittent form. There are only two reported cases of the neuroimaging findings of this disorder, both imaged during an acute metabolic decompensation, with documented abnormalities of the basal ganglia. We report a previously undescribed neuroimaging finding of isolated cerebellar atrophy with normal basal ganglia in a 6-year-old female with chronic intermittent isovaleric acidemia, imaged for evaluation of developmental delay, outside an episode of a metabolic crisis. *Correspondence to: Nicolas-Jilwan M, Department of Radiology, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia, Tel: 9613940781; E-mail: manaljilwan@hotmail.com
{"title":"Isovaleric acidemia: A rare cause of isolated cerebellar atrophy","authors":"N. M.","doi":"10.15761/rdi.1000141","DOIUrl":"https://doi.org/10.15761/rdi.1000141","url":null,"abstract":"Isovaleric acidemia is a very rare autosomal recessive inborn error of leucine metabolism caused by deficiency of the mitochondrial enzyme isovaleryl-coenzyme A dehydrogenase. The disease has two well-known clinical phenotypes: an acute neonatal presentation with severe metabolic crisis and a chronic intermittent form. There are only two reported cases of the neuroimaging findings of this disorder, both imaged during an acute metabolic decompensation, with documented abnormalities of the basal ganglia. We report a previously undescribed neuroimaging finding of isolated cerebellar atrophy with normal basal ganglia in a 6-year-old female with chronic intermittent isovaleric acidemia, imaged for evaluation of developmental delay, outside an episode of a metabolic crisis. *Correspondence to: Nicolas-Jilwan M, Department of Radiology, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia, Tel: 9613940781; E-mail: manaljilwan@hotmail.com","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89407085","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}
The purpose of this study is to find an optimization approach to minimize the absorbed dose to adult patients undergoing CT examination, while maintain the diagnostic image quality. A single detector CT was considered, to represent typical practice in King Hamad University Hospital. We included 626 patients in this study and investigated radiation dose for three anatomical regions, head, chest and abdomen and pelvis. For each type of CT examination, two groups of patients were considered. 383 patients in Group I: were imaged according to the protocols set by the manufacturer. Group II: 243 patients were imaged according to the protocols set by our team after optimization. We were able to adjust the adjustable factors such as noise index, scan time, pitch, rotation time and slice thickness. For each examination the weighted volume CT dose index (CTDIvol) and dose length product (DLP) were recorded and noise is measured. Each study was also reviewed for image quality. Measured (CTDIvol, DLP) were compared to international reference levels. For Group I, the CTDIvol and DLP values were higher than the reference levels. After Dose optimization the CTDIvol and DLP values were significantly reduced to have lower values than the reference levels. The results of our study showed that the CTDIvol and DLP values taken from images done using the protocols set by the Ct machine developers are higher than the reference levels which indicate that manufacturers are focusing their efforts toward improving image quality rather than the minimizing the dose that can be given to the patient. Correspondence to: Lama Sakhnini, Department of Physics, College of Science, University of Bahrain, Sakhir, Kingdom of Bahrain; E-mail: l_ sakhnini@yahoo.com Received: November 1, 2017; Accepted: December 12, 2017; Published: December 15, 2017 Introduction The use of helical, multislice CT (MSCT) is rapidly growing due to technological improvements in the modern machines. Advances in CT imaging techniques have resulted in a significant increase in the frequency of CT examinations in both adult and children, replacing more and more radiographic examinations. However, CT can be responsible for the increase of carcinogenesis [1-4]. But we have to accept the fact that with the vast improvement of technology, patients benefited from a quicker and more accurate diagnosis and precise anatomic information for planning therapeutic procedures. This lead to a substantial increase in the collective dose, as reported by international organizations (ICRP 2000 and United Nations Scientific Committee 2000) [5]. In spite of this constructive contributions of CT to modern healthcare, attention must also be given to the health risk associated with the ionizing radiation received during a CT exam. Because of this potential radiation risk from this increased use of CT makes it important that CT doses be kept as low as reasonably achievable. However, modern CT scanners have a wide variety of exposure
{"title":"CT radiation dose optimization and reduction for routine head, chest and abdominal CT examination","authors":"Lama Sakhnini","doi":"10.15761/RDI.1000120","DOIUrl":"https://doi.org/10.15761/RDI.1000120","url":null,"abstract":"The purpose of this study is to find an optimization approach to minimize the absorbed dose to adult patients undergoing CT examination, while maintain the diagnostic image quality. A single detector CT was considered, to represent typical practice in King Hamad University Hospital. We included 626 patients in this study and investigated radiation dose for three anatomical regions, head, chest and abdomen and pelvis. For each type of CT examination, two groups of patients were considered. 383 patients in Group I: were imaged according to the protocols set by the manufacturer. Group II: 243 patients were imaged according to the protocols set by our team after optimization. We were able to adjust the adjustable factors such as noise index, scan time, pitch, rotation time and slice thickness. For each examination the weighted volume CT dose index (CTDIvol) and dose length product (DLP) were recorded and noise is measured. Each study was also reviewed for image quality. Measured (CTDIvol, DLP) were compared to international reference levels. For Group I, the CTDIvol and DLP values were higher than the reference levels. After Dose optimization the CTDIvol and DLP values were significantly reduced to have lower values than the reference levels. The results of our study showed that the CTDIvol and DLP values taken from images done using the protocols set by the Ct machine developers are higher than the reference levels which indicate that manufacturers are focusing their efforts toward improving image quality rather than the minimizing the dose that can be given to the patient. Correspondence to: Lama Sakhnini, Department of Physics, College of Science, University of Bahrain, Sakhir, Kingdom of Bahrain; E-mail: l_ sakhnini@yahoo.com Received: November 1, 2017; Accepted: December 12, 2017; Published: December 15, 2017 Introduction The use of helical, multislice CT (MSCT) is rapidly growing due to technological improvements in the modern machines. Advances in CT imaging techniques have resulted in a significant increase in the frequency of CT examinations in both adult and children, replacing more and more radiographic examinations. However, CT can be responsible for the increase of carcinogenesis [1-4]. But we have to accept the fact that with the vast improvement of technology, patients benefited from a quicker and more accurate diagnosis and precise anatomic information for planning therapeutic procedures. This lead to a substantial increase in the collective dose, as reported by international organizations (ICRP 2000 and United Nations Scientific Committee 2000) [5]. In spite of this constructive contributions of CT to modern healthcare, attention must also be given to the health risk associated with the ionizing radiation received during a CT exam. Because of this potential radiation risk from this increased use of CT makes it important that CT doses be kept as low as reasonably achievable. However, modern CT scanners have a wide variety of exposure ","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75286461","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}
B. Imen, Babouche Farid, Bouharati Khaoula, H. Mokhtar, Bouharati Saddek
Aim: Often post-mortem radiography as a judicial procedure is intended to know the causes of death. X-rays are systematic on putrefied, charred or severely altered bodies when identifying a body. Nowadays other radiological techniques are used in post mortem recognition. In the case of collective disasters (war, air accident, or industrial ...etc.) the task is easy when comparing ante-mortem radiographs. In the absence of these, vestibular craniography and positional morpho-metric analysis is necessary. Specific characters of a skull are taken into account in this study. It refers us to his race as the first identification. Method: In this study, a database is based on the data that specifying each ethnic group (Gallo-Romans, Japanese, Ainu, Amerindians, Melanesians, African Blacks, Australians, Tasmanians ...). Each group is distinguished by specific characters (the shape of the structures and for their position in the axes, their structure and their reciprocal articulation). From measurements made on radiography skull and artificial neural network analysis, it will be possible to attribute this to the ethnic group to which it belongs. Conclusion: In this study, we consider these characters (distances, circumferences, curve, volumes, and angles) are considered as input variables of the network. These variables are related to an output variable that refers to the individual race. This can be a valuable tool for identification in forensic medicine. Correspondence to: Saddek B, Laboratory of Intelligent Systems, Ferhat Abas UFAS Setif1 University, Algeria, E-mail: sbouharati@univ-setif.dz
目的:作为一种司法程序，尸检放射照相通常是为了了解死亡原因。在鉴定尸体时，对腐烂、烧焦或严重变形的尸体进行系统的x光检查。如今，其他放射学技术也被用于尸体识别。在集体灾难(战争、航空事故或工业事故等)的情况下，比较死前的x光片很容易。在没有这些的情况下，前庭颅骨摄影和位置形态计量分析是必要的。在本研究中考虑了颅骨的具体特征。它让我们把他的种族作为第一个身份。方法:在本研究中，基于指定每个种族(高卢-罗马人，日本人，阿伊努人，美洲印第安人，美拉尼西亚人，非洲黑人，澳大利亚人，塔斯马尼亚人……)的数据建立数据库。每一组都由特定的特征来区分(结构的形状和它们在轴线上的位置，它们的结构和它们的相互连接)。通过对头骨的放射照相测量和人工神经网络分析，将有可能将其归因于所属的种族。结论:在本研究中，我们将这些特征(距离、周长、曲线、体积和角度)视为网络的输入变量。这些变量与指向个体种族的输出变量相关。这可以成为法医学鉴定的宝贵工具。通讯:Saddek B，智能系统实验室，Ferhat abbas UFAS Setif1大学，阿尔及利亚，E-mail: sbouharati@univ-setif.dz
{"title":"An analysis of cranial radiography in post-mortem recognition","authors":"B. Imen, Babouche Farid, Bouharati Khaoula, H. Mokhtar, Bouharati Saddek","doi":"10.15761/rdi.1000124","DOIUrl":"https://doi.org/10.15761/rdi.1000124","url":null,"abstract":"Aim: Often post-mortem radiography as a judicial procedure is intended to know the causes of death. X-rays are systematic on putrefied, charred or severely altered bodies when identifying a body. Nowadays other radiological techniques are used in post mortem recognition. In the case of collective disasters (war, air accident, or industrial ...etc.) the task is easy when comparing ante-mortem radiographs. In the absence of these, vestibular craniography and positional morpho-metric analysis is necessary. Specific characters of a skull are taken into account in this study. It refers us to his race as the first identification. Method: In this study, a database is based on the data that specifying each ethnic group (Gallo-Romans, Japanese, Ainu, Amerindians, Melanesians, African Blacks, Australians, Tasmanians ...). Each group is distinguished by specific characters (the shape of the structures and for their position in the axes, their structure and their reciprocal articulation). From measurements made on radiography skull and artificial neural network analysis, it will be possible to attribute this to the ethnic group to which it belongs. Conclusion: In this study, we consider these characters (distances, circumferences, curve, volumes, and angles) are considered as input variables of the network. These variables are related to an output variable that refers to the individual race. This can be a valuable tool for identification in forensic medicine. Correspondence to: Saddek B, Laboratory of Intelligent Systems, Ferhat Abas UFAS Setif1 University, Algeria, E-mail: sbouharati@univ-setif.dz","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84349876","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}
S. An, L. Yurkova, K. S. Borodulya, L. P. Ekimova, Matyurin Ks
In order to verify the principle of indirect control a tumor on the base of morphogenic cells distraction from it, the 114 patients with advanced ovarian carcinoma were treated with subtotal half-body (low part) irradiation at low doses (0,1 Gy x 10 for 3 weeks or 3Gy x 3 daily), and obtained data were compared with that for 190 patients received conventional local irradiation of the tumor (2 Gy x 23 daily). The surgery and chemotherapy components were equalized in both groups. The 34 % and 11% of 5-years survival was obtained at low dose half body irradiation for primary and relapsed patients in comparison with conventional local radiotherapy (7% and 0%). It is concluded, that reparation /regeneration processes being provoked artificially in normal tissues of cancer host are capable to compete remotely with tumor for the morphogenic/feeding cells originated from bone marrow and circulating with the blood. Correspondence to: Shoutko AN, Russian Research Centre of Radiology and Surgical Technologies, Saint-Petersburg, Russian Federation, Russia, E-mail: shoutko@inbox.ru Received: July 20, 2017; Accepted: August 14, 2017; Published: August 17, 2017 Introduction Conventional medicine recognizes a selective killing of tumor cells as only way of fighting with cancer. This way has brought some doubtless benefits in the past, but in the last decades the effectiveness of traditional treatment progresses more slowly, than it would be desirable. The life span of mammals at normal conditions and chronic irradiation as well depends on limit of proliferative capacity of bone marrow given at the birth [1]. Despite this, a strong mielodepression follows inevitably palliative chemoand radiotherapy of cancer. As we argued earlier, the suppression at “therapeutic” range follows by temporary restrictions a morphogenic cells activity inside a tumor [2]. The morphogenic cells (trophocytes / feeding cells) is presented in the blood by hematopoietic stem cells, pro-lymphocytes, angiogenic T-cells and some others [3-5]. There are two ways to restrict the tumor growth’s support by them: 1) either to provoke a repopulation stem cells in bone marrow by its injuring with relatively high “hemotoxic” doses of “curative” factor, or 2) to redirect the circulating morphogenic cells from tumor toward a reparation/regeneration of numerous but nonlethal injuries in different normal cells, induced by relatively low doses of “curative” toxicants [2]. In both cases the mechanism of expected benefit has to be not direct but the mediated by rearrangement of the tissues renewing’s balance between the cancer and host body. The purpose our presentation is to demonstrate the reliability of described “competitive” approach of cancer therapy at real clinic conditions. Method Since 1995 to 2005 the patients with advanced epithelial ovarian cancer were treated in Russian Research Centre of Radiology and Surgical Technologies of Federal Health Ministry, using 5 MV linear accelerator. The half bo
{"title":"Competitive principal of tumor control in radiological clinic","authors":"S. An, L. Yurkova, K. S. Borodulya, L. P. Ekimova, Matyurin Ks","doi":"10.15761/rdi.1000107","DOIUrl":"https://doi.org/10.15761/rdi.1000107","url":null,"abstract":"In order to verify the principle of indirect control a tumor on the base of morphogenic cells distraction from it, the 114 patients with advanced ovarian carcinoma were treated with subtotal half-body (low part) irradiation at low doses (0,1 Gy x 10 for 3 weeks or 3Gy x 3 daily), and obtained data were compared with that for 190 patients received conventional local irradiation of the tumor (2 Gy x 23 daily). The surgery and chemotherapy components were equalized in both groups. The 34 % and 11% of 5-years survival was obtained at low dose half body irradiation for primary and relapsed patients in comparison with conventional local radiotherapy (7% and 0%). It is concluded, that reparation /regeneration processes being provoked artificially in normal tissues of cancer host are capable to compete remotely with tumor for the morphogenic/feeding cells originated from bone marrow and circulating with the blood. Correspondence to: Shoutko AN, Russian Research Centre of Radiology and Surgical Technologies, Saint-Petersburg, Russian Federation, Russia, E-mail: shoutko@inbox.ru Received: July 20, 2017; Accepted: August 14, 2017; Published: August 17, 2017 Introduction Conventional medicine recognizes a selective killing of tumor cells as only way of fighting with cancer. This way has brought some doubtless benefits in the past, but in the last decades the effectiveness of traditional treatment progresses more slowly, than it would be desirable. The life span of mammals at normal conditions and chronic irradiation as well depends on limit of proliferative capacity of bone marrow given at the birth [1]. Despite this, a strong mielodepression follows inevitably palliative chemoand radiotherapy of cancer. As we argued earlier, the suppression at “therapeutic” range follows by temporary restrictions a morphogenic cells activity inside a tumor [2]. The morphogenic cells (trophocytes / feeding cells) is presented in the blood by hematopoietic stem cells, pro-lymphocytes, angiogenic T-cells and some others [3-5]. There are two ways to restrict the tumor growth’s support by them: 1) either to provoke a repopulation stem cells in bone marrow by its injuring with relatively high “hemotoxic” doses of “curative” factor, or 2) to redirect the circulating morphogenic cells from tumor toward a reparation/regeneration of numerous but nonlethal injuries in different normal cells, induced by relatively low doses of “curative” toxicants [2]. In both cases the mechanism of expected benefit has to be not direct but the mediated by rearrangement of the tissues renewing’s balance between the cancer and host body. The purpose our presentation is to demonstrate the reliability of described “competitive” approach of cancer therapy at real clinic conditions. Method Since 1995 to 2005 the patients with advanced epithelial ovarian cancer were treated in Russian Research Centre of Radiology and Surgical Technologies of Federal Health Ministry, using 5 MV linear accelerator. The half bo","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83351041","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}
Computers have revolutionized the field of diagnostic imaging and are absolutely essential in modern radiology practices [1]. First introduced into the radiology department in the 1960’s, computers’ role drastically expanded with the development of Radiology Information Systems (RIS). The earliest uses of computer technology related to imaging acquisition were nuclear medicine, digital subtraction angiography, computerized tomography (CT) in the 1970’s, and magnetic resonance imaging (MRI) in the 1980’s. The next major development was the picture archiving and communication systems (PACS). By the 2000’s, many practices had converted to voice recognition software from transcriptionist. Also in the 2000’s screening mammography computer aided detection (CAD) was reimbursed by insurance companies which precipitated its widespread adoption [2-4]. An area of current opportunity in the breast imaging world is the intersection several newly available technologies. Simultaneously, the American College of Radiology (ACR) has created a campaign to guide radiology called “Imaging 3.0.” This program emphasizes the importance of adding value on behalf of all stakeholders including patients, hospital systems, and payers. Application of several new technologies may help achieve the goals of Imaging 3.0.
{"title":"Review of contemporary computing technology to enhance breast imaging","authors":"R. Mayo","doi":"10.15761/RDI.1000117","DOIUrl":"https://doi.org/10.15761/RDI.1000117","url":null,"abstract":"Computers have revolutionized the field of diagnostic imaging and are absolutely essential in modern radiology practices [1]. First introduced into the radiology department in the 1960’s, computers’ role drastically expanded with the development of Radiology Information Systems (RIS). The earliest uses of computer technology related to imaging acquisition were nuclear medicine, digital subtraction angiography, computerized tomography (CT) in the 1970’s, and magnetic resonance imaging (MRI) in the 1980’s. The next major development was the picture archiving and communication systems (PACS). By the 2000’s, many practices had converted to voice recognition software from transcriptionist. Also in the 2000’s screening mammography computer aided detection (CAD) was reimbursed by insurance companies which precipitated its widespread adoption [2-4]. An area of current opportunity in the breast imaging world is the intersection several newly available technologies. Simultaneously, the American College of Radiology (ACR) has created a campaign to guide radiology called “Imaging 3.0.” This program emphasizes the importance of adding value on behalf of all stakeholders including patients, hospital systems, and payers. Application of several new technologies may help achieve the goals of Imaging 3.0.","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"144 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78500279","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}
FDG PET-CT imaging is a standard method in diagnosis, staging and follow-up in lymphoma patients. In this case report, leukemic-lymphomatous infiltration findings on PET/CT imaging in a NHL patient was demonstrated and differential diagnosis were presented in patients with diffuse large B-cell lymphoma diagnosed by PET-CT for initial staging. Correspondence to: Assoc Prof. Pelin Ozcan Kara, Mersin University Hospital, Nuclear Medicine Department, Mersin/Turkey; Tel: 903242410000; Fax: 903242410098; E-mail: ppelinozcan@gmail.com
{"title":"PET-CT of leukemic-lymphomatous muscle ınfiltration","authors":"P. Kara, Z. Koç, A. Tombak","doi":"10.15761/RDI.1000115","DOIUrl":"https://doi.org/10.15761/RDI.1000115","url":null,"abstract":"FDG PET-CT imaging is a standard method in diagnosis, staging and follow-up in lymphoma patients. In this case report, leukemic-lymphomatous infiltration findings on PET/CT imaging in a NHL patient was demonstrated and differential diagnosis were presented in patients with diffuse large B-cell lymphoma diagnosed by PET-CT for initial staging. Correspondence to: Assoc Prof. Pelin Ozcan Kara, Mersin University Hospital, Nuclear Medicine Department, Mersin/Turkey; Tel: 903242410000; Fax: 903242410098; E-mail: ppelinozcan@gmail.com","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74486124","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}
E. Grassi, F. Fioroni, E. Mezzenga, D. Finocchiaro, M. Sarti, A. Filice, A. Versari, M. Iori
The purpose of this study was to investigate the influence of the Ordered Subsets Expectation Maximization (OSEM) reconstruction updates implemented in the 177Lu SPECT/CT imaging processing in molecular radiotherapy. A NEMA IEC Body PhantomTM was used to quantify activity in refillable spheres of five different sizes. Images were obtained with a hybrid dual-head SPECT-CT imaging system (Symbia T2, Siemens Medical System, Germany) with a clinical acquisition protocol, and reconstructed using a commercial 3D OSEM algorithm (Flash 3D). In the reconstruction process, different values of iterations and subsets were considered, along with a 3D Gaussian post-reconstruction filter and scatter and attenuation correction. Activity recovery coefficients were derived from the ratio between total reconstructed counts and the true activity for each sphere at each OSEM update. Recovery coefficients, and average fractional error (i.e. the weighted Root Mean Squared Error) were evaluated. At the same time, also 177Lu spatial resolution and dead time were investigated, as matter of discussion about activity recovery coefficients. Results for spheres ≤ 5.5 ml in volume were significantly affected by the partial volume effect, causing a great bias in activity estimation for the smallest spheres. Their weighted fractional error was OSEM update dependent, ranging between 85% to 79% and 60% to 50% for the two smallest spheres, referring to values of 8 subsets-8 iterations and 16 subsets-10 iterations for the two extremes, respectively. No dead time was detected. The choice of iterations and subsets is dependent on the object size to investigate and on the desired image quality. Anyway, using a fixed number of iterations and subsets is correct for objects with volumes ≥ 5.5 ml, reaching the total count convergence in the reconstructed volumes, but the use of correction factors for compensating the partial volume effect is needed. For objects with volumes ≤ 5.5 ml the quantification becomes challenging. Correspondence to: Dr. Elisa Grassi, Medical Physics Unit, IRCCS-ASMN, Viale Risorgimento 57, 42123 Reggio Emilia, Italy; E-mail: elisa.grassi@asmn.re.it
本研究的目的是探讨有序子集期望最大化(OSEM)重建更新对分子放疗中177Lu SPECT/CT成像处理的影响。使用NEMA IEC Body PhantomTM来量化五种不同大小的可填充球体的活性。使用混合双头SPECT-CT成像系统(Symbia T2, Siemens Medical system, Germany)获得具有临床采集协议的图像，并使用商用3D OSEM算法(Flash 3D)重建图像。在重建过程中，考虑了不同的迭代和子集值，并进行了三维高斯重建后滤波和散射和衰减校正。活度恢复系数由每次OSEM更新时每个球体的总重建计数与真实活度之比导出。评估恢复系数和平均分数误差(即加权均方根误差)。同时研究了177Lu的空间分辨率和死区时间，作为活度恢复系数的讨论内容。体积≤5.5 ml的微球受部分体积效应影响显著，对最小微球的活性估计偏差较大。他们的加权分数误差与OSEM更新有关，对于两个最小的球体，分别参考8个子集(8次迭代)和16个子集(10次迭代)的值，范围在85%到79%之间，60%到50%之间。未检测到死区时间。迭代和子集的选择取决于要研究的对象大小和所需的图像质量。无论如何，对于体积≥5.5 ml的物体，使用固定次数的迭代和子集是正确的，在重建的体积中达到总数收敛，但需要使用校正因子来补偿部分体积效应。对于体积≤5.5 ml的物体，定量变得具有挑战性。通讯:Elisa Grassi博士，医学物理组，IRCCS-ASMN, Viale Risorgimento 57, 42123 Reggio Emilia，意大利;电子邮件:elisa.grassi@asmn.re.it
{"title":"Impact of a commercial 3D OSEM reconstruction algorithm on the 177Lu activity quantification of SPECT/CT imaging in a Molecular Radiotherapy trial","authors":"E. Grassi, F. Fioroni, E. Mezzenga, D. Finocchiaro, M. Sarti, A. Filice, A. Versari, M. Iori","doi":"10.15761/RDI.1000101","DOIUrl":"https://doi.org/10.15761/RDI.1000101","url":null,"abstract":"The purpose of this study was to investigate the influence of the Ordered Subsets Expectation Maximization (OSEM) reconstruction updates implemented in the 177Lu SPECT/CT imaging processing in molecular radiotherapy. A NEMA IEC Body PhantomTM was used to quantify activity in refillable spheres of five different sizes. Images were obtained with a hybrid dual-head SPECT-CT imaging system (Symbia T2, Siemens Medical System, Germany) with a clinical acquisition protocol, and reconstructed using a commercial 3D OSEM algorithm (Flash 3D). In the reconstruction process, different values of iterations and subsets were considered, along with a 3D Gaussian post-reconstruction filter and scatter and attenuation correction. Activity recovery coefficients were derived from the ratio between total reconstructed counts and the true activity for each sphere at each OSEM update. Recovery coefficients, and average fractional error (i.e. the weighted Root Mean Squared Error) were evaluated. At the same time, also 177Lu spatial resolution and dead time were investigated, as matter of discussion about activity recovery coefficients. Results for spheres ≤ 5.5 ml in volume were significantly affected by the partial volume effect, causing a great bias in activity estimation for the smallest spheres. Their weighted fractional error was OSEM update dependent, ranging between 85% to 79% and 60% to 50% for the two smallest spheres, referring to values of 8 subsets-8 iterations and 16 subsets-10 iterations for the two extremes, respectively. No dead time was detected. The choice of iterations and subsets is dependent on the object size to investigate and on the desired image quality. Anyway, using a fixed number of iterations and subsets is correct for objects with volumes ≥ 5.5 ml, reaching the total count convergence in the reconstructed volumes, but the use of correction factors for compensating the partial volume effect is needed. For objects with volumes ≤ 5.5 ml the quantification becomes challenging. Correspondence to: Dr. Elisa Grassi, Medical Physics Unit, IRCCS-ASMN, Viale Risorgimento 57, 42123 Reggio Emilia, Italy; E-mail: elisa.grassi@asmn.re.it","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91124422","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}
Magnetic resonance imaging (MRI) of the pediatric brain has provided us with great insight into the maturation processes that take place after birth. However, in order for us to derive benefits from the information provided to us, it is imperative for us to first establish normality. This is extremely challenging especially in the first 2 years of life as the appearance of a normal brain changes according to the stage of development. Changes in normal appearances, clues on how to differentiate them from true pathologies as well as their clinical significance are outlined in this article. Several points of confusion that commonly arise in reviewing MR images of pediatric brain are emphasized, including 1) What are the normal signal intensities within the brain? When do we make a diagnosis of HIE or periventricular leukomalacia? 2) Ventriculomegaly : Is it benign external hydrocephalus, ex-vacuo ventricular dilatation or communicating hydrocephalus? 3) Corpus callosum : More than just another midline structure. When to call it abnormal, what are the common associated abnormalities and how to use it to estimate the time of insult? 4) Thickened cerebral cortex : Malformations of cortical development (MCD) and “pseudothickening” of cortex 5) Dandy Walker syndrome, inferior vermian hypoplasia, persistent Blake pouch cyst or mega cisterna magna?
{"title":"Pediatric MRI Brain: Normal or abnormal, that is the question.","authors":"A. Tan","doi":"10.15761/RDI.1000112","DOIUrl":"https://doi.org/10.15761/RDI.1000112","url":null,"abstract":"Magnetic resonance imaging (MRI) of the pediatric brain has provided us with great insight into the maturation processes that take place after birth. However, in order for us to derive benefits from the information provided to us, it is imperative for us to first establish normality. This is extremely challenging especially in the first 2 years of life as the appearance of a normal brain changes according to the stage of development. Changes in normal appearances, clues on how to differentiate them from true pathologies as well as their clinical significance are outlined in this article. Several points of confusion that commonly arise in reviewing MR images of pediatric brain are emphasized, including 1) What are the normal signal intensities within the brain? When do we make a diagnosis of HIE or periventricular leukomalacia? 2) Ventriculomegaly : Is it benign external hydrocephalus, ex-vacuo ventricular dilatation or communicating hydrocephalus? 3) Corpus callosum : More than just another midline structure. When to call it abnormal, what are the common associated abnormalities and how to use it to estimate the time of insult? 4) Thickened cerebral cortex : Malformations of cortical development (MCD) and “pseudothickening” of cortex 5) Dandy Walker syndrome, inferior vermian hypoplasia, persistent Blake pouch cyst or mega cisterna magna?","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"223 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77789509","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}
Objective: To investigate the practice and attitudes of Medical radiologic technologists (MRTs’)/radiographers on the use of Gonad shielding (GS)in pediatric radiological imaging. Methods: A questionnaire regarding MRTs’ attitudes and on the use of Gonad shielding was developed based on relevant literatures and distributed to MRTs/ radiographers working in general radiography at Black Lion and St. Paul hospitals in a study period from June to August 2014. Descriptive (percentage of frequency) study was used to analyze the responses of the multiple choices. A separate questionnaire was prepared to evaluate the practice of GS in these two hospitals. Results: The radiographers had shown a positive attitude towards using GS, however none of them used it in daily practice for a various reason such as (GS may obscure region of interest 11.1%, uncooperative patient 16.7%, too busy 13.9%, GS not available 27.8% and no appropriate size GS 27.8%). The investigators had also reviewed 94 abdominal-pelvic radiographs and none was taken with application of GS. Conclusion: Although the radiographers had a positive attitude, none of them had applied GS while taking plain radiographs and/or CT scan in and around the gonads. Updates on their knowledge on gonadal shielding and enforcing every medical imaging technologist to comply with hospital protocols are recommended. Correspondence to: Dr. SeifeTeferi, Assistance professor of Medical Physics Addis Ababa University College of Health sciences, school of medicine, Department of Radiology; Tel: +25192905456; E-mail: seifeteferi@yahoo.com
{"title":"Preliminary study on the practice of gonad shielding during pelvic radiography","authors":"Seife Teferi, Yodit Tequabo, Daniel Bedane","doi":"10.15761/RDI.1000105","DOIUrl":"https://doi.org/10.15761/RDI.1000105","url":null,"abstract":"Objective: To investigate the practice and attitudes of Medical radiologic technologists (MRTs’)/radiographers on the use of Gonad shielding (GS)in pediatric radiological imaging. Methods: A questionnaire regarding MRTs’ attitudes and on the use of Gonad shielding was developed based on relevant literatures and distributed to MRTs/ radiographers working in general radiography at Black Lion and St. Paul hospitals in a study period from June to August 2014. Descriptive (percentage of frequency) study was used to analyze the responses of the multiple choices. A separate questionnaire was prepared to evaluate the practice of GS in these two hospitals. Results: The radiographers had shown a positive attitude towards using GS, however none of them used it in daily practice for a various reason such as (GS may obscure region of interest 11.1%, uncooperative patient 16.7%, too busy 13.9%, GS not available 27.8% and no appropriate size GS 27.8%). The investigators had also reviewed 94 abdominal-pelvic radiographs and none was taken with application of GS. Conclusion: Although the radiographers had a positive attitude, none of them had applied GS while taking plain radiographs and/or CT scan in and around the gonads. Updates on their knowledge on gonadal shielding and enforcing every medical imaging technologist to comply with hospital protocols are recommended. Correspondence to: Dr. SeifeTeferi, Assistance professor of Medical Physics Addis Ababa University College of Health sciences, school of medicine, Department of Radiology; Tel: +25192905456; E-mail: seifeteferi@yahoo.com","PeriodicalId":11275,"journal":{"name":"Diagnostic imaging","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77267612","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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