Comparison study of image quality at various radiation doses for CT venography using advanced modeled iterative reconstruction

Jung Han Hwang; Jin Mo Kang; So Hyun Park; Suyoung Park; Jeong Ho Kim; Sang tae Choi

doi:10.1371/journal.pone.0256564

Peer Review History

Original SubmissionApril 1, 2021
26 May 2021 Decision Letter - Mingwu Jin, Editor PONE-D-21-10760 Comparison study of image quality at various radiation doses for CT venography using advanced modeled iterative reconstruction PLOS ONE Dear Dr. Park, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. More details of the points raised by the reviewers and editor can be found in their comments at the end of this letter. Please submit your revised manuscript by Jul 10 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols. We look forward to receiving your revised manuscript. Kind regards, Mingwu Jin, Ph.D. Academic Editor PLOS ONE Additional Editor Comments: The reviewers raised the major concerns about the feasibility of CT protocol and the lack of comparison of bench-mark methods, such as FBP. The latter may be necessary to establish that the model-based iterative reconstruction algorithm (ADMIRE) is essential for low-dose CT venogram. In addition, the readers' experience and performance difference should be provided for the subjective evaluation. Addressing these issues would greatly improve the significance of the paper. Journal Requirements: When submitting your revision, we need you to address these additional requirements. 1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf 2. We note that you have indicated that data from this study are available upon request. 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Please also provide contact information for a data access committee, ethics committee, or other institutional body to which data requests may be sent. b) If there are no restrictions, please upload the minimal anonymized data set necessary to replicate your study findings as either Supporting Information files or to a stable, public repository and provide us with the relevant URLs, DOIs, or accession numbers. Please see http://www.bmj.com/content/340/bmj.c181.long for guidelines on how to de-identify and prepare clinical data for publication. For a list of acceptable repositories, please see http://journals.plos.org/plosone/s/data-availability#loc-recommended-repositories. We will update your Data Availability statement on your behalf to reflect the information you provide. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: No Reviewer #2: No ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: No Reviewer #2: Yes ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes ****** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: A review of the paper titled “Comparison study of image quality at various radiation doses for CT venography using advanced modeled iterative reconstruction” Thank for letting me review this work! It is good to see we can go lower in dose using this scanner/recon for these indications and not suffer issues. General Comments: 1. The abstract needs some attention. The conclusion statement says “using a reconstruction algorithm allows” I think you need to say “using an advanced model based iterative reconstruction algorithm” 2. It is not clear from the abstract that you compare regular and lower dose non advanced recon to lower dose advanced recon. You need to do this to support your conclusions to prove it was the advanced recon that enabled the dose reduction. Or else how to do we know the overall dose was just set too high? I assume you did this in the paper itself, but reading the abstract itself, this important study design point is not clear. For example, I can scan at 100 mGy using FBP and then cut it to 50 mGy and use ADMIRE. But concluding ADMIRE allowed a reduction w/o issues for diagnostic purposes is flawed…I would need to show at 50 mGy with FBP I performed worse. 1. Introduction: I don’t think this sentence means what you intend “The radiation exposure during CT venography is becoming an increasing concern 67 because the mean dose level rises when a patient requires multiple CT examinations during the 68 disease process of pulmonary embolism (chest CT) or given the recurrency of DVT” There is no reason for the mean dose the pt gets to change, I think you mean their cumulative effective dose is rising as they get more and more scans? Using CED as a motivation for dose reduction is kind of controversial, an exam, if indicated and appropriate should be given w/o concern for stochastic cancer risk. This is the position of the American College of Radiology and the American Association of Physicists in Medicine. 2. Introduction: I think there a lot of papers out there for this, please cite more (I went to google scholar and found several on the first page of results you don’t cite on this topic) and consider changing the verbiage/tone of this paragraph, to something more like “there are many papers in the literature looking at dose reduction with lower kV and advanced model based recons…we are contributing to this space by looking specifically at … a. “Few 69 studies have reported the reduction of the average radiation dose for CT venography using low 70 tube voltages, mono-energy CT, and iterative reconstruction algorithms” 3. There is no stat testing for the reader scores/ Just for the noise measurements? 4. The paper concludes it is recon method that enables the low dose visualization, but we cannot conclude this from your methods. The scores seem to basically be the same or just differ by 1 point from low to high dose, with more variation being pt to pt. I think in order to support that the lower dose was enabled by advanced recon, you must prove to us the images are not fit for diagnostic purposes if the ADMIRE recon was not used? Specific Comments: 1. In the CT protocol section, can you elaborate on what the 70 and 30% refer to? Was the actual mAs equal to what you have listed, or was 70 and 30% used? Reviewer #2: In this manuscript, the author evaluated image quality of three radiation dose levels for CT venography. The results showed low- and ultralow-dose CT venography at 80 kV had acceptable image quality. Comments 1) My biggest question is that how it was possible for the author to run the Siemens Force scanner with both tubes at 80 kV and different tube currents. For Siemens Force scanner, all the clinical protocols using two sources are in either dual-energy mode or dual-source mode. The dual-energy mode has one tube high kV and one tube low kV. In dual-source mode, both tubes are using the same tube current. Did the author use some special service mode or collaborate with Siemens to config the protocols? Otherwise, it is not possible to scan using the protocols described in the manuscript. 2) Line 42. CT dose index volume is not “calculated” but displayed on the dose page. I don’t think there was any calculation about CTDIvol in the manuscript. 3) The abstract needs to mention the special setup of the protocols using dual-source CT. 4) Have the author tried the CarekV, an automatic kV selection tool used by Siemens CT? How does it compare to 80 kV method used in the manuscript? ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review?** For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No Reviewer #2: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. 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Revision 1
2 Jul 2021 Author Response Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: No Reviewer #2: No 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: No Reviewer #2: Yes 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: A review of the paper titled “Comparison study of image quality at various radiation doses for CT venography using advanced modeled iterative reconstruction” Thank for letting me review this work! It is good to see we can go lower in dose using this scanner/recon for these indications and not suffer issues. General Comments: 1. The abstract needs some attention. The conclusion statement says “using a reconstruction algorithm allows” I think you need to say “using an advanced model based iterative reconstruction algorithm” Response: Thank you for your comment. We have changed the abstract as suggested “Low- and ultralow-dose CT venography at 80 kVp using an advanced model based iterative reconstruction algorithm” (R1-1). 2. It is not clear from the abstract that you compare regular and lower dose non advanced recon to lower dose advanced recon. You need to do this to support your conclusions to prove it was the advanced recon that enabled the dose reduction. Or else how to do we know the overall dose was just set too high? I assume you did this in the paper itself, but reading the abstract itself, this important study design point is not clear. For example, I can scan at 100 mGy using FBP and then cut it to 50 mGy and use ADMIRE. But concluding ADMIRE allowed a reduction w/o issues for diagnostic purposes is flawed…I would need to show at 50 mGy with FBP I performed worse. Response: Thank you for your comment. We were routinely inspecting the lower extremity CT venography using ADMIRE on a CT machine (Force). At that time, we conducted using caredose at 300 reference mAs when carekVp was set at 80kVp. It would have been a superior study comparing images with FBP reconstructing and those with ADMIRE regarding dose reduction. However, raw data work will be needed to reconstruct FBP images in comparison with ADMIRE images. We did not perform the work. We have added the limitation of the study in the manuscript (R1-2). Currently, major CT vendors introduced iterative reconstruction algorithms for clinical routine, which evolved rapidly into increasingly advanced reconstruction algorithms. Most dose-reduction strategies remained in the domain of decreasing tube current or tube voltage while iterative reconstruction algorithms insure an acceptable diagnostic image quality. Therefore, we focused on dose reduction study of intraindividual comparison using ADMIRE. 1. Introduction: I don’t think this sentence means what you intend “The radiation exposure during CT venography is becoming an increasing concern 67 because the mean dose level rises when a patient requires multiple CT examinations during the 68 disease process of pulmonary embolism (chest CT) or given the recurrency of DVT” There is no reason for the mean dose the pt gets to change, I think you mean their cumulative effective dose is rising as they get more and more scans? Using CED as a motivation for dose reduction is kind of controversial, an exam, if indicated and appropriate should be given w/o concern for stochastic cancer risk. This is the position of the American College of Radiology and the American Association of Physicists in Medicine. Response: Thank you for your comment. We have removed the sentence as suggested (R1-3) 2. Introduction: I think there a lot of papers out there for this, please cite more (I went to google scholar and found several on the first page of results you don’t cite on this topic) and consider changing the verbiage/tone of this paragraph, to something more like “there are many papers in the literature looking at dose reduction with lower kV and advanced model based recons…we are contributing to this space by looking specifically at … a. “Few 69 studies have reported the reduction of the average radiation dose for CT venography using low 70 tube voltages, mono-energy CT, and iterative reconstruction algorithms” Response) Thank you for your comment. We have changed the introduction and added several references as suggested (R1-4, There are many studies in the literature investigating at radiation dose reduction with low tube voltages and advanced model based reconstruction. We are contributing to this space by specifically looking at..). 3. There is no stat testing for the reader scores/ Just for the noise measurements? Response: Thank you for your comment. Two radiologists reviewed subjective image analysis (i.e. scores) in consensus. We did not analyze interobserver variability. We only measured attenuation and image noise. Therefore, we added the limitation of this study in the manuscript (R1-5). We analyzed differences of subjective image quality and image noise of three image sets using a one-way analysis of variance with post-hoc analysis and Bonferroni correction. 4. The paper concludes it is recon method that enables the low dose visualization, but we cannot conclude this from your methods. The scores seem to basically be the same or just differ by 1 point from low to high dose, with more variation being pt to pt. I think in order to support that the lower dose was enabled by advanced recon, you must prove to us the images are not fit for diagnostic purposes if the ADMIRE recon was not used? Response: Thank you for your comment. We did not analyze diagnostic performance for DVT detection or compare between images with filtered back projection and those with ADMIRE. We have added our study’s limitation (we did not analyze diagnostic performance for DVT detection) and change in the conclusion (~ADMIRE show acceptable image quality for DVT evaluation~, R1-6). Specific Comments: 1. In the CT protocol section, can you elaborate on what the 70 and 30% refer to? Was the actual mAs equal to what you have listed, or was 70 and 30% used? Response: We used 70% and 30% reference mAs, compared with reference mAs on standard CT. The actual mAs also showed 70% and 30% ratio (low-dose and ultralow-dose), compared with standard dose CT. Reviewer #2: In this manuscript, the author evaluated image quality of three radiation dose levels for CT venography. The results showed low- and ultralow-dose CT venography at 80 kV had acceptable image quality. Comments 1) My biggest question is that how it was possible for the author to run the Siemens Force scanner with both tubes at 80 kV and different tube currents. For Siemens Force scanner, all the clinical protocols using two sources are in either dual-energy mode or dual-source mode. The dual-energy mode has one tube high kV and one tube low kV. In dual-source mode, both tubes are using the same tube current. Did the author use some special service mode or collaborate with Siemens to config the protocols? Otherwise, it is not possible to scan using the protocols described in the manuscript. Response: Thank you for your comment. To perform the specific split of the tube dose (mAs) between tube detector A and B, the CT scanner requires a dual energy research license. We added the feature in the material and method (R2-1). 2) Line 42. CT dose index volume is not “calculated” but displayed on the dose page. I don’t think there was any calculation about CTDIvol in the manuscript. Response: Thank you for your comment. We changed the word, as “displayed” (R2-2). 3) The abstract needs to mention the special setup of the protocols using dual-source CT. Response: Thank you for your comment. We added the protocol in methods section, “in the dual-source mode in tubes A (reference mAs, 210 mAs at 70%) and B (reference mAs, 90 mAs at 30%) at a fixed 80 kVp” (R2-3). 4) Have the author tried the CarekV, an automatic kV selection tool used by Siemens CT? How does it compare to 80 kV method used in the manuscript? Response: Thank you for your comment. In Siemens CT, selection of automatic kVp or fixed kVp is possible. However, using the specific split of the tube dose in a dual source mode, we select a specific kVp (i.e, did not use automatic kVp change). Therefore, we selected fixed 80 kVp and compared between specific radiation doses. https://doi.org/10.1371/journal.pone.0256564.r002
2 Aug 2021 Decision Letter - Mingwu Jin, Editor PONE-D-21-10760R1 Comparison study of image quality at various radiation doses for CT venography using advanced modeled iterative reconstruction PLOS ONE Dear Dr. Park, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please re-address the comment 4 of Reviewer 2 about CarekV from last review. Since CarekV is a standard package on the scanner for the same purpose of this study, please add some discussion about the limitation of this study if the experiment suggested by the reviewer can't be conducted. Please submit your revised manuscript by Sep 16 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols. We look forward to receiving your revised manuscript. Kind regards, Mingwu Jin, Ph.D. Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #1: All comments have been addressed Reviewer #2: (No Response) ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: The authors have addressed my concerns. The major issue I had was that we cannot claim it was the advanced recon that allowed the dose reduction, I think the authors have changed the paper's verbiage to account for the fact their study never compared FBP low dose to ADMIRE low dose directly. Thanks. Reviewer #2: (No Response) ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: Yes:** Timothy P Szczykutowicz Reviewer #2: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0256564.r003
Revision 2
5 Aug 2021 Author Response Editor Please re-address the comment 4 of Reviewer 2 about CarekV from last review. Since CarekV is a standard package on the scanner for the same purpose of this study, please add some discussion about the limitation of this study if the experiment suggested by the reviewer can't be conducted. Response: Thank you for your comment. We have added the limitation as suggested “Fourth, we selected fixed 80 kVp and compared between specific radiation doses. Selection of automatic kVp change or fixed kVp is possible in Siemens CT. However, using the specific split of the tube dose in a dual source mode, we can only select a specific kVp (i.e, cannot use automatic kVp change).” (Editor). Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. Response: Thank you for your comment. Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #1: All comments have been addressed Reviewer #2: (No Response) 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes Reviewer #2: Yes 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: Yes 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: The authors have addressed my concerns. The major issue I had was that we cannot claim it was the advanced recon that allowed the dose reduction, I think the authors have changed the paper's verbiage to account for the fact their study never compared FBP low dose to ADMIRE low dose directly. Thanks. Reviewer #2: (No Response) 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: Yes: Timothy P Szczykutowicz Reviewer #2: No Response 1~7): Thank you for your helpful comment. Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0256564.r004
10 Aug 2021 Decision Letter - Mingwu Jin, Editor Comparison study of image quality at various radiation doses for CT venography using advanced modeled iterative reconstruction PONE-D-21-10760R2 Dear Dr. Park, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Mingwu Jin, Ph.D. Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0256564.r005
Formally Accepted
23 Aug 2021 Acceptance Letter - Mingwu Jin, Editor PONE-D-21-10760R2 Comparison study of image quality at various radiation doses for CT venography using advanced modeled iterative reconstruction Dear Dr. Park: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Mingwu Jin Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0256564.r006

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