Craniocervical SurgeryVENAMAP 2NCT07206667
Improved Understanding of Venous Drainage at the Cranio-cervical Junction : Study of Postoperative Venous Remodeling Following Surgical Treatment of Lesions of the Posterior Fossa or Posterior Approach of the Upper Cervical Spine.
A study testing T1 GRE GADO MRI sequence in people with Craniocervical Surgery, run by University Hospital, Brest at 1 site in France.
Trial summary
In the literature, a dichotomous view of cerebral venous drainage is most commonly found. Thus, two drainage pathways are most often considered: the jugular vein network and the vertebral artery plexus. However, several clinical observations seem to indicate a much more complex situation. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Craniocervical Surgery
- What is being tested?
- T1 GRE GADO MRI sequence
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteFrance
- Study dates
- 1 Jul 2026to 1 Nov 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patient:
- Adult
- Surgery of the posterior cranial fossa or posterior approach to the upper cervical spine, regardless of indication, performed in the neurosurgery department at Brest University Hospital
- Having undergone an MRI with T1 echo gradient sequence with gadolinium (T1 TFE GADO)
- Affiliated with a Social Security scheme
- Having given written consent to participate in the study
Who cannot join
- Pregnant or breastfeeding women
- Allergy to gadolinium
- Any contraindications to undergoing an MRI scan (incompatible medical device implant, claustrophobia, etc.)
- Patients unable to understand the protocol
- Patients under guardianship or conservatorship
- Patients subject to a future protection order, family authorization, or legal protection
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
France1 site
CHU Brest
Brest, Brittany Region, 29200
Romuald SEIZEUR, Pr, +33 230 337 802, romuald.seizeur@chu-brest.fr
About this study
In the literature, a dichotomous view of cerebral venous drainage is most commonly found. Thus, two drainage pathways are most often considered: the jugular vein network and the vertebral artery plexus. However, several clinical observations seem to indicate a much more complex situation.
The following hypothesis is therefore put forward: there are alternative drainage pathways to these main pathways, which are physiologically present and capable of draining a significant volume of blood. A set of alternative pathways, which can be described as "deep," has been described: in particular, drainage pathways surrounding the vertebral artery (vertebral artery venous plexus), epidural plexuses, and deep cervical veins. However, the so-called "superficial" systems (subcutaneous and muscular) do not appear to have been studied.
Read more
There appears to be a change in venous drainage of the craniocervical junction postoperatively (posterior cranial fossa surgery and posterior approach to the upper cervical spine).
These modifications would vary depending on the venous drainage configuration present in each patient. If this hypothesis is confirmed, it could have an impact on the management of each patient. Thus, if venous remodeling models are established, this could enable personalized perioperative patient management: better optimization of body position during installation in the operating room, more effective anticipation of potential intraoperative venous bleeding, and explanation of persistent headaches in the postoperative period due to insufficient compensation of venous drainage. Confirmation of this hypothesis would also improve the understanding of certain pathologies for which the venous hypothesis has been raised (chronic hydrocephalus in adults, idiopathic intracranial hypertension, etc.).
Read the detailed description
Inclusion:
The inclusion visit will take place during an initial neurosurgery consultation. If the patient meets the inclusion and exclusion criteria and wishes to participate in this study, the study investigator will obtain the patient's consent.
During this visit, a routine MRI will be performed if the patient has not already had one. In addition to the standard procedure, this MRI will include the study-specific T1 GRE GADO MRI sequence, which will add approximately 3 minutes to the usual examination. The patient will also undergo a routine neurological clinical examination and data about them will be collected (informative data about the patient (age, sex, BMI, etc.), medical history, neurological functional signs, reason for treatment, and neurological clinical examination).
First follow-up visit:
During hospitalization in the neurosurgery department, the patient will undergo a routine neurological clinical examination and data will be collected intraoperatively (duration of surgery, blood loss, ligation/clipping/any interventions on venous structures, intraoperative hemorrhage, other complications of all types) as well as early postoperative data (complications, types, headaches).
The time between the preoperative visit and surgery varies and may depend on the patient's surgical indication.
Second follow-up visit:
Finally, the patient will be asked to come to the neurosurgery department for a post-operative visit a few weeks after their surgery.
This visit is part of standard practice and includes a clinical neurological examination.
During this visit, a second MRI will be performed using the specific sequence for the study, T1 GRE GADO, which will add approximately 3 minutes to the routine examination. Data concerning the patient will be collected (complications, types, headaches).
- Conditions
- Craniocervical Surgery
- Being tested
- T1 GRE GADO MRI sequence
- Keywords
- neurosurgery, cerebral venous drainage, MRI
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
T1 GRE GADO MRI sequenceProcedure or surgery
Addition of a T1 gradient echo sequence with gadolinium (T1 TFE GADO) during the two MRI scans performed in routine practice before and after neurosurgery.
| Study group | Role | What they receive |
|---|---|---|
| Single arm (all patients) | Experimental | During the two routine MRI scans, a T1 GRE GADO MRI sequence (specific to the study) will be added. It lasts approximately 3 minutes. Receives: Procedure: T1 GRE GADO MRI sequence |
What is being measured
The primary outcome is the main question the study is designed to answer.
Dominant network before and after surgery in the craniocervical junction
The primary endpoint is identification of the dominant network before and after surgery in the craniocervical junction (i.e., 3 months after surgery).
A T1 echo gradient sequence with gadolinium (T1 TFE GADO), lasting approximately 3 minutes, will be added to the MRIs performed as part of routine care before and after surgery on patients.
A double reading of the MRI will be performed:
- First by a neurosurgery intern,
- Secondly, by a senior neuroradiology investigator who is blinded to the measurements taken by the neurosurgery intern.
- In the event of a discrepancy between the two observers, the values obtained by the senior radiologist will be retained.
The percentage change in the dominant network will be presented with its 95% confidence interval.
Measured: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Secondary outcomes (5)
Dominant network before and after surgery in the craniocervical junction and type of surgery
A T1 echo gradient sequence with gadolinium (T1 TFE GADO), lasting approximately 3 minutes, will be added to the MRIs performed as part of routine care before and after surgery on patients.
A double reading of the MRI will be performed:
- First by a neurosurgery intern,
- Secondly, by a senior neuroradiology investigator who is blinded to the measurements taken by the neurosurgery intern.
- In the event of a discrepancy between the two observers, the values obtained by the senior radiologist will be retained.
The percentage change in dominant network by type of surgery (Oncological skull surgery, Non-oncological skull surgery, Emergency spinal surgery and Elective spinal surgery) and the percentage change in lateralization of dominance will be presented with their 95% confidence interval.
Measured: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Dominance (right/left) of venous drainage before and after surgery
A T1 echo gradient sequence with gadolinium (T1 TFE GADO), lasting approximately 3 minutes, will be added to the MRIs performed as part of routine care before and after surgery on patients.
A double reading of the MRI will be performed:
- First by a neurosurgery intern,
- Secondly, by a senior neuroradiology investigator who is blinded to the measurements taken by the neurosurgery intern.
- In the event of a discrepancy between the two observers, the values obtained by the senior radiologist will be retained.
The percentage change in dominant network by type of surgery and the percentage change in lateralization of dominance will be presented with their 95% confidence interval.
Measured: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Total surface area of vessels before and after surgery, overall and within each venous network of the craniocervical junction.
A T1 echo gradient sequence with gadolinium (T1 TFE GADO), lasting approximately 3 minutes, will be added to the MRIs performed as part of routine care before and after surgery on patients.
A double reading of the MRI will be performed:
- First by a neurosurgery intern,
- Secondly, by a senior neuroradiology investigator who is blinded to the measurements taken by the neurosurgery intern.
- In the event of a discrepancy between the two observers, the values obtained by the senior radiologist will be retained.
The mean surface differences (overall, by venous network, and by lateralization of initial dominance) will be presented with their 95% confidence interval.
Measured: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Total surface area of vessels before and after surgery and initial dominance
A T1 echo gradient sequence with gadolinium (T1 TFE GADO), lasting approximately 3 minutes, will be added to the MRIs performed as part of routine care before and after surgery on patients.
A double reading of the MRI will be performed:
- First by a neurosurgery intern,
- Secondly, by a senior neuroradiology investigator who is blinded to the measurements taken by the neurosurgery intern.
- In the event of a discrepancy between the two observers, the values obtained by the senior radiologist will be retained.
The mean surface differences (overall, by venous network, and by lateralization of initial dominance) will be presented with their 95% confidence interval.
Measured: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Vessel diameter according to internal assessment and senior radiologist
The agreement between the measurement of vessel diameters by the intern or the experienced radiologist will be assessed graphically using the Bland and Altman method and numerically using the intraclass correlation coefficient accompanied by its 95% confidence interval estimated using the Fleiss method. The intraclass correlation coefficient will be interpreted using the following correspondences:
- < 0.50: Unacceptable
- 0.51-0.60: Low
- 0.61-0.70: Mediocre
- 0.71-0.80: Satisfactory
- 0.81-0.90: Fairly good
- 0.91-0.95: Very good
- 0.95: Excellent
Measured: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Oct 2025
- Study start1 Jul 2026 (estimated)
- Primary completion1 Nov 2029 (estimated)
- Study completion1 Nov 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Craniocervical SurgeryStudies of the same condition, open and under way.
- More trials run by University Hospital, BrestThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Single-center exploratory prospective study
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Hospital, Brest
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07206667
- Sponsor's protocol ID
- 29BRC24.0305
- Other IDs
- 2025-A00646-43
- Acronym
- VENAMAP 2
- Status last verified
- May 2026
- First submitted
- 26 Sep 2025
- Last updated
- 29 May 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: All collected data that underlie results in a publication
Study at a glance
From the registry record, last updated by the sponsor on 29 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Improved Understanding of Venous Drainage at the Cranio-cervical Junction : Study of Postoperative Venous Remodeling Following Surgical Treatment of Lesions of the Posterior Fossa or Posterior Approach of the Upper Cervical Spine.
- ClinicalTrials.gov ID
- NCT07206667
- Acronym / sponsor ID
- VENAMAP 2 / 29BRC24.0305
- Conditions
- Craniocervical Surgery
- Keywords
- neurosurgery, cerebral venous drainage, MRI
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- University Hospital, BrestUniversity, hospital or other
- Study start
- 1 Jul 2026 (estimated)
- Primary completion
- 1 Nov 2029 (estimated)
- Study completion
- 1 Nov 2029 (estimated)
- First posted
- 3 Oct 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
In the literature, a dichotomous view of cerebral venous drainage is most commonly found. Thus, two drainage pathways are most often considered: the jugular vein network and the vertebral artery plexus. However, several clinical observations seem to indicate a much more complex situation.
The following hypothesis is therefore put forward: there are alternative drainage pathways to these main pathways, which are physiologically present and capable of draining a significant volume of blood. A set of alternative pathways, which can be described as "deep," has been described: in particular, drainage pathways surrounding the vertebral artery (vertebral artery venous plexus), epidural plexuses, and deep cervical veins. However, the so-called "superficial" systems (subcutaneous and muscular) do not appear to have been studied.
There appears to be a change in venous drainage of the craniocervical junction postoperatively (posterior cranial fossa surgery and posterior approach to the upper cervical spine).
These modifications would vary depending on the venous drainage configuration present in each patient. If this hypothesis is confirmed, it could have an impact on the management of each patient. Thus, if venous remodeling models are established, this could enable personalized perioperative patient management: better optimization of body position during installation in the operating room, more effective anticipation of potential intraoperative venous bleeding, and explanation of persistent headaches in the postoperative period due to insufficient compensation of venous drainage. Confirmation of this hypothesis would also improve the understanding of certain pathologies for which the venous hypothesis has been raised (chronic hydrocephalus in adults, idiopathic intracranial hypertension, etc.).
Detailed description
Inclusion:
The inclusion visit will take place during an initial neurosurgery consultation. If the patient meets the inclusion and exclusion criteria and wishes to participate in this study, the study investigator will obtain the patient's consent.
During this visit, a routine MRI will be performed if the patient has not already had one. In addition to the standard procedure, this MRI will include the study-specific T1 GRE GADO MRI sequence, which will add approximately 3 minutes to the usual examination. The patient will also undergo a routine neurological clinical examination and data about them will be collected (informative data about the patient (age, sex, BMI, etc.), medical history, neurological functional signs, reason for treatment, and neurological clinical examination).
First follow-up visit:
During hospitalization in the neurosurgery department, the patient will undergo a routine neurological clinical examination and data will be collected intraoperatively (duration of surgery, blood loss, ligation/clipping/any interventions on venous structures, intraoperative hemorrhage, other complications of all types) as well as early postoperative data (complications, types, headaches).
The time between the preoperative visit and surgery varies and may depend on the patient's surgical indication.
Second follow-up visit:
Finally, the patient will be asked to come to the neurosurgery department for a post-operative visit a few weeks after their surgery.
This visit is part of standard practice and includes a clinical neurological examination.
During this visit, a second MRI will be performed using the specific sequence for the study, T1 GRE GADO, which will add approximately 3 minutes to the routine examination. Data concerning the patient will be collected (complications, types, headaches).
Study design
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Single-center exploratory prospective study
| Arm | Type | Receives |
|---|---|---|
| Single arm (all patients) | Experimental | Procedure: T1 GRE GADO MRI sequenceDuring the two routine MRI scans, a T1 GRE GADO MRI sequence (specific to the study) will be added. It lasts approximately 3 minutes. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Adult
- Surgery of the posterior cranial fossa or posterior approach to the upper cervical spine, regardless of indication, performed in the neurosurgery department at Brest University Hospital
- Having undergone an MRI with T1 echo gradient sequence with gadolinium (T1 TFE GADO)
- Affiliated with a Social Security scheme
- Having given written consent to participate in the study
Key exclusion criteria (6 listed)
- Pregnant or breastfeeding women
- Allergy to gadolinium
- Any contraindications to undergoing an MRI scan (incompatible medical device implant, claustrophobia, etc.)
- Patients unable to understand the protocol
- Patients under guardianship or conservatorship
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| T1 GRE GADO MRI sequenceAddition of a T1 gradient echo sequence with gadolinium (T1 TFE GADO) during the two MRI scans performed in routine practice before and after neurosurgery. | Procedure or surgery | Single arm (all patients) |
Primary outcome
Dominant network before and after surgery in the craniocervical junction
Time frame: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
The primary endpoint is identification of the dominant network before and after surgery in the craniocervical junction (i.e., 3 months after surgery). A T1 echo gradient sequence with gadolinium (T1 TFE GADO), lasting approximately 3 minutes, will be added to the MRIs performed as part of routine care before and after surgery on patients. A double reading of the MRI will be performed: * First by a neurosurgery intern, * Secondly, by a senior neuroradiology investigator who is blinded to the measurements taken by the neurosurgery intern. * In the event of a discrepancy between the two observers, the values obtained by the senior radiologist will be retained. The percentage change in the dominant network will be presented with its 95% confidence interval.
5 secondary outcomes
Dominant network before and after surgery in the craniocervical junction and type of surgery
Time frame: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Dominance (right/left) of venous drainage before and after surgery
Time frame: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Total surface area of vessels before and after surgery, overall and within each venous network of the craniocervical junction.
Time frame: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Total surface area of vessels before and after surgery and initial dominance
Time frame: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Vessel diameter according to internal assessment and senior radiologist
Time frame: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 May 2026.
- Individual participant dataSharing planned: Yes. All collected data that underlie results in a publication
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing T1 GRE GADO MRI sequence in people with Craniocervical Surgery, run by University Hospital, Brest at 1 site in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 29 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Romuald SEIZEUR, Pr (+33 230 337 802, romuald.seizeur@chu-brest.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Dominant network before and after surgery in the craniocervical junction (time frame: Pre-surgery MRI (performed up to 12 weeks before surgery) + Post-surgery MRI (performed between 10 days and 16 weeks after surgery)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 May 2026.