PONE-D-20-31294

The diagnostic function of intravoxel incoherent motion for distinguishing between pilocytic astrocytoma and ependymoma

PLOS ONE

Dear Dr. Minh Duc,

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.

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   Please response the questions from the reviewers.
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   Lack of correlation with the classical DSC perfusion.

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PLOS ONE

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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: Partly

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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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

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #1: Yes

Reviewer #2: Yes

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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: Introduction:

- References [1-3] are cited three times. Please cite them only once.

- Line 15: coonfirmed o be==> confirmed to be

- You say IVIM was "recently" described- It was described in the 80s, so please use other expression.

Data acquisition:

- How many different observers perfomed the measures? How much experience in pediatric Neurorradiology did they have?

Was it unblinded or blinded?

- How many ROIs were used?

- Please describe the methods for hystopathologic diagnosis

Results:

- Group 1 and 2: Please define what group was each type of tumor.

- In order to analyze the advantages of IVIM measurements compared to teh use of ADC it would be interesting to compare values of ADC in both type of tumors too in this study.

Discussion

Line 25:It would be intersting to present hystopathological data of anti CD31 in this study

Reviewer #2: In this study, the authors have analyzed the IVIM imaging for the diagnostic's distinction between ependymoma and pilocytic astrocytoma. The results are quite clear demonstrating a significant D and f values between these two tumors. The D value derived from IVIM is the most essential factor. The IVIM sequence is interesting because it makes it possible to dispense with the injection of a contrast agent in order to estimate tumoral perfusion. The interest of this study is its application on tumors not explored in previous studies which are focused on metastasis, low and high grade glioma, meningioma and lymphoma. The limits of this study are the small numbers of patients and the lack of correlation with the classical DSC perfusion (which has been done in other glioma studies).

I have some comments about this article:

1) This study was conducted on a 1.5T. Are there any studies comparing IVIM sequence between magnetic fields?

2) The lesion characteristics are not detailed, in particular the tumor sizes which may participate to partial volume effect.

3) The authors used the Philips software, would it be possible to have the estimation model: classic monoexponential or biexponential?

4) Some recent references are missing:

Ki-67 labeling index and the grading of cerebral gliomas by using intravoxel incoherent motion diffusion-weighted imaging and three-dimensional arterial spin labeling magnetic resonance imaging. Chaochao Wang , Haibo Dong Acta Radiol . 2020 Aug;61(8):1057-1063.

Correlation and Characteristics of Intravoxel Incoherent Motion and Arterial Spin Labeling Techniques Versus Multiple Parameters Obtained on Dynamic Susceptibility Contrast Perfusion MRI for Brain Tumors. Enkh-Amgalan olgorsuren, Masafumi Harada, Yuki Kanazawa , Takashi Abe, Maki Otomo, Yuki Matsumoto, Yoshifumi Mizobuchi, Kohhei Nakajima. J. Med. Invest.. 2019;66(3.4):308-313. The conclusion of this study is that compared to DSC, the ASL-CBF is more suitable for the evaluation of perfusion in brain tumors than IVIM parameters and should be discussed.

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Reviewer #1: Yes: Nerea Domínguez-Pinilla

Reviewer #2: No

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The diagnostic function of intravoxel incoherent motion for distinguishing between pilocytic astrocytoma and ependymoma

PONE-D-20-31294R1

Dear Dr. Minh Duc,

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.

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Kind regards,

Quan Jiang, Ph,D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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

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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

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: 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

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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

**********

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: (No Response)

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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.

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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: Nerea Domínguez-Pinilla