Occipital Pial AVM Rupture in a Young Adult: Dual Intranidal Aneurysms, Solitary Parasagittal SSS Drainage, and Hematoma-Corridor Microsurgical Cure

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Abstract

"The clinical significance of posteroconvexity pial arteriovenous malformations (AVMs) is the ability for a seemingly small lesion to lead to rupture of the lesion due to micro-architecture stresses at focal points and constricted egress through veins. The combination of a size-severity mismatch in a young, low compliance skull, can result in sudden collapse of the intracranial pressure with acute and severe localized damage to the posterior cerebral network. Therefore we sought to demonstrate that bedside phenotyping based on topological features of the AVMS could predict the site of potential weakness in the AVMS and provide evidence supporting corridor-directed therapy"

Please, rephrase. A case report cannot demonstrate your hypothesis. 

I suggest to check the whole manuscript for anatomical terms to be changed or clarified (e.g. "posteroconvexity"). 

"Modified Rankin scale (MRS)" is modified Rankin Scale (mRS).

"rapid arousal failure": do you mean rapid decrease in alertness? Coma? If yes, I suggest to write it and give a GCS score. 

"developed a cortical-subcortical syndrome affecting his right parieto-occipital cortex": it is not clear to me what do you mean in neurological terms. Please, list neurolgoical signs and, if not evaluable because of coma, please, state it. 

I do not think that angiography is the first diagnostic techniqie used in this case. The previous steps were skipped. Please, add them.  You wrote the patient has an hematoma (maybe better name it as ICH +/- SAH and SDH) after describing angiographic findings. 

"The AVM was fed by distal cortical branches of the middle cerebral artery (MCA), showed rapid arteriovenous transit time, and contained two large saccular aneurysms located within the AVM. Drainage from the AVM was exclusively superficial via a single cortical vein into the superior sagittal sinus." The description is not functional to the therapy in the abstract; I suggest to be more focused: nidus location, feeding arteries, drainage routes, arterial/or venous aneurysms and on what artery. Please, follow the usual order: 1. NCCT showing ICH; 2. CTA (or DSA, it is not clear) with the AVM; 3. Treatment options in emergency and your choices. 

AVMS?

"bridged veins": do you mean bridging veins? 

"neutralizing the low flow aneurysms": I suggest to rephrase. 

"The patient recovered rapidly, and returned to his premorbid state of function except for a small area of residual quadrantanopia": then, the patient did not returned to the previous condition. I suggest to rephrase

I suggest to rephrase the conclusions, taking into account that it is a case report and you firstly mentionaed "nidus" in the conclusions. In addition, "posterior cerebral network" han not be studied before in the presented patient (at least in the abstract). 

 

Keywords

I suggest to double check these ones: "feeder-first devascularization; vein-last division; young adult rupture phenotype"

 

Introduction: 

Pial AVM may also be slow-flow, so I think you should be more comprehensive in the general description of disease. 

"concurrent with a sudden decrease in cranial vault compliance in a young skull with low compensatory reserve": I suggest to separate clinical signs from mechanical events in two different sentences.

"We present a case of a young adult who sustained": please, rephrase (underwent instead of sustained?)

Again, you are describing a single case report. technically, you cannot demonstrate anything using this approach., You can apply an hypothesis, you can use the hypothesis as a guide to perform treatment and you can describe this process, but you cannot demonstrate any hypothesis in a single case report. Then, I suggest to rephrase the last few sentences of the introduction. 

By the way, it is not bad if you declare in the background the involved organ (brain). 

 

Case presentation

"pre-event mRS of 0": you have to write mRS in full the first time you mention it in the full text

"He presented to us acutely and in rapid sequence with a hyperacute neurologic collapse with symptoms compatible with a high volume lobar hemorrhage located in the posterior convexity region." 

Sorry, but neurologic collapse is not an acceptable description from a neurological point of view. Please, rephrase the sentence, considering that the patient had a neurological deficit and due to this deficit you performed diagnostic tests finding ICH. The deficit itself can help to localize a putative lesion in the brain and not to guess its nature. 

See previous comments fo "failure of arousal". 

"Given the simultaneous emergence of explosive intracranial hypertension physiology and a sharply focal cortical syndrome, alternative explanatory frameworks (primary headache disorder, intoxication, metabolic derangement, or infection-first constructs) were biologically implausible; therefore, from the first bedside assessment, the working diagnosis centered on rupture of a high-flow neurovascular lesion, most consistent with a pial AVM."

Please, rephrase using the correct order of a clinical evaluation and reasoning without trying to guess diseases. At what time of his clinical worsening the patient fynally got a CT evaluation?

The remaining part of the description is proposed in the same way. I suggest to rephrase the whole text in order to propose a reasonable way of clinical thinking without skipping fundamental steps. I cannot think you used automated pupillometry instead (or before) a brain CT scan. 

 

The overall impression resulting from the proposed description is a lack of clarity in the timeline and the stages of reasoning, starting with the clinical stage. Some key stages are missing, which aren't even present in the narrative, but which are essential to achieving the authors' focus: the functional description of the AVM angioarchitecture as a guide to treatment selection and management. The message the authors wish to convey is interesting and detailed, but this detracts from its value and visibility. Furthermore, many of the proposed explanations are speculations that cannot be supported by the investigations performed on a single case alone and represent deviations from the linear description of the clinical presentation and treatment. I suggest avoiding discussion of the potential impact of posterior cortical network involvement in a patient with ICH and suggest presenting and describing ICH and its topography/imaging features, etc.

 

Author Response

Dear Esteemed Academic Reviewer,

We sincerely thank you for the time, care, and intellectual rigor you devoted to the evaluation of our manuscript. Your comments were thoughtful, precise, and clinically grounded, and they prompted a comprehensive re-examination of our work. We are particularly grateful for your emphasis on neurological accuracy, logical clinical sequencing, and appropriate interpretation of a single-case report, as these points helped us substantially improve clarity, terminology, and scientific balance throughout the manuscript. We appreciate the opportunity to revise our work in response to your suggestions and believe the resulting version is significantly strengthened as a result of your input.

 

 

ABSTRACT

Comment: “Please rephrase. A case report cannot demonstrate your hypothesis.”
Response: We fully agree. We revised the Abstract to avoid any language implying demonstration or proof.

 

 

Comment: “Check anatomical terms to be changed/clarified (e.g., ‘posteroconvexity’).”
Response: Thank you. We performed a global terminology review and replaced ambiguous or non-standard anatomical terms throughout the manuscript.

 

 

Comment: “Modified Rankin scale (MRS) is modified Rankin Scale (mRS).”
Response: We agree and corrected this throughout the manuscript. The first occurrence now reads modified Rankin Scale (mRS), and subsequent occurrences use mRS consistently.

 

 

Comment: “‘rapid arousal failure’: do you mean rapid decrease in alertness? Coma? If yes, write it and give a GCS score.”
Response: Thank you for highlighting this. We revised this phrasing to the clinically appropriate term “rapid decline in alertness/level of consciousness” and explicitly included the admission GCS (11; E3V3M5) in both the Abstract and Case Presentation. We also preserved the FOUR score in the full text as an adjunct measure, while ensuring that the primary description remains clinically standard.

 

 

Comment: “‘developed a cortical-subcortical syndrome…’ not clear. Please list neurological signs.”
Response: We fully agree. We removed the vague phrase and replaced it with a direct, objective neurological description (left pyramidal weakness with MRC grading, visual field deficit with macular sparing, visuospatial neglect, NIHSS scoring, and pupillometry findings). Where evaluation was limited by the patient’s reduced alertness, we explicitly stated this.

 

 

Comment: “I do not think angiography is the first diagnostic technique… add previous steps. You wrote hematoma after angiography. Please add steps and use ICH ± SAH/SDH if appropriate.”
Response: We agree and thank you for this important correction. We revised the Abstract and Case Presentation to follow the standard diagnostic workflow.

 

Comment: “Angio description not functional to therapy in abstract; be focused: nidus location, feeding arteries, drainage routes, aneurysm location. Follow order: NCCT; CTA/DSA; treatment options and choices.”
Response: Thank you. We also clarified that the vascular study performed was catheter DSA with 3D reconstructions.

 

 

Comment: “AVMS?”
Response: Correct. We replaced AVMS with the standard plural AVMs throughout the manuscript.

 

 

Comment: “‘bridged veins’: do you mean bridging veins?”
Response: Yes. We corrected terminology to bridging veins throughout.

 

 

Comment: “‘neutralizing the low flow aneurysms’: rephrase.”
Response: We agree. We replaced this phrase with a more precise intraoperative description, indicating that the intranidal aneurysmal weak points were addressed/treated during progressive devascularization after inflow reduction, without implying unmeasured flow conditions.

 

 

Comment: “Returned to premorbid state except quadrantanopia → then not fully returned.”
Response: We agree and revised this statement.

 

 

Comment: “Rephrase conclusions; case report; nidus mentioned first time; posterior cerebral network not studied.”
Response: Thank you. We completely revised the Abstract conclusion to avoid speculative network-based claims and to keep the conclusion strictly anchored in clinically demonstrated and therapy-relevant observations.

 

 

Comment: Keywords: double check “feeder-first devascularization; vein-last division; young adult rupture phenotype.”
Response: We reviewed the Keywords and refined them to ensure consistency with indexing standards and the revised language of the manuscript.

 

 

INTRODUCTION

Comment: “Pial AVM may also be slow-flow; be more comprehensive.”
Response: We agree and revised the Introduction to clarify that AVM hemodynamics are variable and not uniformly high-flow. The revised text now describes AVMs as lesions with diverse hemodynamic configurations depending on nidus compactness, feeder resistance, drainage capacity, and associated aneurysmal weak points.

 

 

Comment: “Separate clinical signs from mechanical events.”
Response: Thank you. We revised this segment to separate the clinical syndrome (neurologic deficits and impaired alertness) from mechanistic interpretation (reduced compliance / pressure physiology) into distinct sentences, improving precision and reducing mechanistic overstatement.

 

 

Comment: “‘sustained’: rephrase (underwent?)”
Response: We agree and rephrased for clarity and tone (e.g., “presented with,” “experienced,” “underwent rupture-related hemorrhage”), avoiding awkward or imprecise constructions.

 

 

Comment: “Again: cannot demonstrate hypothesis; rephrase last sentences; declare involved organ (brain).”
Response: We revised the final portion of the Introduction.

 

 

CASE PRESENTATION

Comment: “Write mRS in full the first time.”
Response: Done. The first mention now reads modified Rankin Scale (mRS).

 

 

Comment: “Neurologic collapse is not acceptable; rephrase; describe neurological deficit and CT evaluation.”
Response: We agree and rewrote the opening of the Case Presentation to use clinically acceptable terminology and objective descriptors (thunderclap headache, vomiting, photophobia, progressive decline in alertness, GCS/FOUR scores, focal deficits).

 

 

Comment: “Rephrase reasoning without guessing diseases; avoid speculative frameworks; clarify when CT was performed.”
Response: Thank you. We restructured the case narrative to follow the standard clinical sequence.

 

 

Comment: “Timeline unclear; key stages missing; avoid speculation about posterior network; emphasize ICH topography/imaging; functional angioarchitecture guiding therapy.”
Response: We strongly agree. We revised the entire Case Presentation to improve timeline clarity and remove unsupported explanatory speculation.

 

 

Once again, we thank the Reviewer for these insightful comments. We believe the revised manuscript is substantially improved in clinical precision, logical sequencing, and appropriate interpretation for a single-case report. We are grateful for the opportunity to incorporate these recommendations, which have strengthened both clarity and scientific rigor.

Reviewer 2 Report

Comments and Suggestions for Authors

This is an interesting case report of an occipital pail AV malformation treated surgically.

The authors provided an extremely detailed description of the clinical history and neurological examination prior to the surgical procedure. In an era when the diagnosis is essentially made with the help of imaging, this is a great example of old fashioned way to diagnose brain lesions.

I agree with the surgical option over the endovascular procedure because of the young age of the patient and the small size of the AVM.

I would like to see a pre-op CT scan to evaluate the size of hematoma.

The author should discuss whether an endovascular procedure can be done in these cases.

The post-op remarkable and fast recovery of this patients was certainly due to their surgical skills, but also because a large hematoma was evacuated and the mass effect disappeared. This needs to be discussed. 

Finally, was a post-op Angio done?

Author Response

Dear Esteemed Academic Reviewer,

We thank you for your thoughtful evaluation of our manuscript and for your constructive, clinically grounded comments. We are particularly grateful for your recognition of the value of detailed bedside neurological examination and classical localization, an approach we aimed to preserve as a complementary discipline to imaging-based diagnosis. We also appreciate your agreement regarding the suitability of microsurgical management in this young patient with a small, superficial AVM.

In response to your specific points, we have revised the manuscript accordingly, as detailed below.

 

Comment 1: “I would like to see a pre-op CT scan to evaluate the size of hematoma.”

Response:
We fully agree that a pre-operative non-contrast CT (NCCT) image would strengthen the case report by visually demonstrating hematoma volume and mass effect. Accordingly, we expanded the textual description of the pre-operative NCCT findings in the Case Presentation to more explicitly convey hematoma topography and its surgical relevance. However, we are unfortunately unable to include the pre-operative CT figure itself.

 

 

Comment 2: “The author should discuss whether an endovascular procedure can be done in these cases.”

Response:
We greatly appreciate this suggestion and agree that the discussion should explicitly address the role of endovascular therapy in similar clinical scenarios. We have therefore added a focused paragraph to the Discussion clarifying that endovascular embolization can indeed be considered in ruptured AVMs.

 

 

Comment 3: “The post-op remarkable and fast recovery… was certainly due to surgical skills, but also because a large hematoma was evacuated and the mass effect disappeared. This needs to be discussed.”

Response:
We strongly agree with your interpretation and appreciate the reminder to explicitly attribute recovery not only to resection but also to decompression.

 

 

Comment 4: “Finally, was a post-op Angio done?”

Response:
Thank you for raising this important point. Postoperative catheter angiography was not performed in this case.

The decision was based on: the patient’s uncomplicated postoperative course and rapid neurological recovery, stable postoperative structural imaging without any features suspicious for residual shunting, and the fact that catheter angiography, while definitive, is invasive and carries a small but meaningful procedural risk (arterial injury, thromboembolic complications, contrast exposure), particularly in a young patient.

 

 

Once again, we are grateful for your helpful review and for the positive tone with which you engaged our work. Your suggestions significantly improved the clinical completeness and interpretive balance of the manuscript.

With respectful appreciation!!!

Reviewer 3 Report

Comments and Suggestions for Authors

The authors described a case with occipital pial AVM rupture. Although this case is interesting, I have some comments.

 

1. This case report is too long. The authors spent nearly 5000 words on case presentation.
2. Line 232, …the lesion was located in the right posterior convexity and the lesion was hypothesized to be a rupture-first vascular… I agree with that, but I wonder why brain CT scan was not performed before DSA.
3. The topological features of compact occipital nidus, dual intranidal aneurysms, and solitary superficial parasagittal drainage can easily cause rupture. Are there any references to support the idea? Maybe there is evidence in this manuscript, but the article is too lengthy and I cannot find it.
4. The manuscript should be more concise before the second review.

Author Response

Dear Esteemed Academic Reviewer,

Thank you very much for taking the time to read our case report so carefully and for offering such direct, practical guidance. We genuinely appreciate both the scientific focus of your comments and the editorial discipline behind them. Your feedback helped us improve the manuscript in exactly the way a case report should be improved: clearer, tighter, and easier to navigate.

 

Length / readability (≈5000 words in the Case Presentation).
We fully agree that the original version was overly long for a case report and that the density obscured the central message. In the revised manuscript we substantially condensed the Case Presentation removing repetitive explanatory passages and speculative detours while preserving the clinically relevant details (timeline, neurologic findings, imaging sequence, operative steps, and outcomes). Our goal was to keep the paper information-rich, but much more readable.

 

CT before angiography.
You are absolutely right. 

 

Supporting references for the rupture-prone angioarchitecture.
We appreciate this point in particular. The concept that a compact nidus, intranidal aneurysms, and non-redundant superficial drainage may be associated with hemorrhagic presentation needs to be anchored in the literature and easy to locate.

 

Overall concision before further review.
We agree completely. Beyond shortening, we worked to increase “signal-to-noise”: a more linear timeline, fewer interpretive leaps, and a sharper focus on what this case can responsibly contribute—namely, a practical, angioarchitecture-informed surgical rationale in the setting of hemorrhage where a hematoma corridor exists.

Thank you again for your thoughtful critique. We are grateful for the opportunity to revise along these lines and we believe the manuscript is now substantially clearer and more appropriately scoped.

With profound appreciation!!!

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Fine for me. No further comments from my side.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have revised the manuscript and answered the questions in a satisfactory fashion