# Towards standardised contrast injection protocols in diagnostic cerebral angiography for unruptured aneurysm evaluation: Addressing the current variability and technical challenges

Nicolas Dehlinger, Jean-Philippe Dillenseger, Raoul Pop, Anca Hasiu, Louis

Bonnard, Ian Leonard-Lorant

► To cite this version:

Nicolas Dehlinger, Jean-Philippe Dillenseger, Raoul Pop, Anca Hasiu, Louis Bonnard, et al. Towards standardised contrast injection protocols in diagnostic cerebral angiography for unruptured aneurysm evaluation: Addressing the current variability and technical challenges. Radiography, 2025, pp.103254. 10.1016/j.radi.2025.103254. hal-05536528

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Review article

# Towards standardised contrast injection protocols in diagnostic cerebral angiography for unruptured aneurysm evaluation: Addressing the current variability and technical challenges

N. Dehlinger<sup>a,b,*</sup>, J.-P. Dillenseger<sup>b,c,d</sup>, R. Pop<sup>a,d,e,f</sup>, A. Hasiu<sup>a,d</sup>, L. Bonnard<sup>a,d</sup>, I. Leonard-Lorant<sup>a</sup>

ARTICLE INFO

Article history:

Received 12 September 2025

Received in revised form

27 October 2025

Accepted 10 November 2025

Available online xxx

Keywords:

Cerebral angiography

Intracranial aneurysm

Iodinated contrast media

Optimisation

Evidence-based practice

Interventional neuroradiology

ABSTRACT

**Objectives:** Diagnostic cerebral angiography remains the gold standard for the evaluation of intracranial aneurysms, but current practices regarding iodinated contrast media (ICM) injection are highly variable. No standardised recommendations exist, affecting patient safety, comfort, and diagnostic reliability. This review summarises current practices and highlight the potential of applying the ALADA – As Low As Diagnostically Acceptable – principle to ICM injections, emphasising the role of the interventional neuroradiologist-radiographer team in promoting safe, patient-centred, and robust procedures.

**Key findings:** Injection parameters reported in the literature presented significant heterogeneity. In 2D DSA of the internal carotid artery (ICA), volumes range from 5.0 to 10.0 mL at 3.0–7.0 mL/s. For the vertebral artery (VA), volumes range from 4.5 to 8.0 mL with flow rates between 2.5 and 5.0 mL/s. In 3D-RA, acquisitions are conducted using injection volumes between 10.0 and 36.0 mL at 1.5–5.0 mL/s for ICA, and 10.0–24.0 mL at 2.0–5.0 mL/s for VA. These variations highlight the large potential for rational optimisation, to reduce ICM exposure, and consequently the risk of contrast-induced nephropathy and adverse reactions, while improving patient tolerance and maintaining diagnostic reliability.

**Conclusion:** Application of the ALADA principle to ICM injections in cerebral angiography is currently unexplored, but it clearly offers a path towards safer, patient-centred and evidence-based practice.

**Implications for practice:** Developing harmonised, quantitative guidelines for ICM injection in cerebral angiography would support protocol standardisation, enhance patient safety, and strengthen the role of radiographers in implementing optimised practices.

© 2025 The Author(s). Published by Elsevier Ltd on behalf of The College of Radiographers. This is an open access article under the CC BY license ([http://creativecommons.org/licenses/by/4.0/](http://creativecommons.org/licenses/by/4.0/)).

Introduction

Diagnostic cerebral angiography is an interventional neurora-
diology (INR) procedure involving arterial access, most common
via the femoral or radial artery, allowing selective catheterisation
of the supra-aortic vessels (carotid and vertebral arteries).¹,² This

approach allows intra-arterial injection of iodinated contrast me-
dia (ICM),³ via a power injector, selectively opacifying the vascular
territories of interest. It enables high-resolution, superimposition-
free visualisation of the cerebral arterial network using dynamic
2D digital subtraction angiography (DSA) or 3D rotational angi-
ography (3D RA).⁴,⁵

While diagnostic cerebral angiography is performed for various
neurovascular conditions, intracranial aneurysm is the most
common indication.⁶,⁷ Despite significant advances in non-
invasive imaging techniques, including magnetic resonance angi-
ography (MRA) and computed tomography angiography (CTA),
cerebral catheter angiography remains the gold standard for
detailed morphological assessment of aneurysms.⁸ It allows

<footnote><sup>a</sup>Department of Interventional Neuroradiology, Strasbourg University Hospitals, Strasbourg, France</footnote>

<footnote><sup>b</sup>Pole d'imagerie Médicale, Hôpitaux Universitaires de Strasbourg, Strasbourg, France</footnote>

<footnote><sup>c</sup>ICube – UMR 7357, CNRS, Université de Strasbourg, Strasbourg, France</footnote>

<footnote><sup>d</sup>Faculté de Médecine, Maïeutique et des Sciences de la Santé, Université de Strasbourg, Strasbourg, France</footnote>

<footnote><sup>e</sup> Institut de Chirurgie Minime Invasive Guidée par l'Image, Strasbourg, France</footnote>

<footnote><sup>f</sup>INSERM UMR_S1255, Établissement Français du Sang, Strasbourg, France</footnote>

<footnote>This article is part of a special issue entitled: Interventional SI published in
Radiography.</footnote>

<footnote>* Corresponding author. Hôpitaux Universitaires de Strasbourg, 1 Place de l'Hôpital, Cedex, 67091, Strasbourg, France.</footnote>

<footnote>E-mail address: nicolas.dehlinger@chru-strasbourg.fr (N. Dehlinger).</footnote>
precise visualisation of the aneurysmal neck, its relationship with adjacent arteries, and hemodynamic characteristics, key elements in guiding management strategy. The frequent and repetitive nature of aneurysm assessment, whether for initial evaluation, longitudinal follow-up or pre-treatment planning (endovascular or surgical), represent a particularly suitable context for studying injection protocols.

Over the past two decades, INR has made significant strides in terms of safety,⁹ particularly through the systematic application of the ALARA (As Low As Reasonably Achievable) principle for radiation protection, as promoted by the ICRP.¹⁰⁻¹² However, the management of ICM administration remains problematic. To date, no numerical guidelines exist for the application of a comparable principle to ICM — such as ALADA (As Low As Diagnostically Acceptable)¹³ — to control practices and limit exposure. The ACR-ASNR-SIR-SNIS recommendations provide general guidance for safely performing cervicocerebral catheter angiography, including the management of ICM injection.¹ They suggest that injection should be performed at a sufficient volume and flow rate to achieve adequate opacification of the vascular territory of interest. Nonetheless, no quantitative thresholds or specific parameters are proposed, leaving room for operator-dependent variability. Similarly, CIRSE and ESUR provide broad recommendations regarding ICM administration in interventional and diagnostic imaging. Nonetheless, these documents are limited and lack detailed, evidence-based instructions on injection parameters, offering no objective basis to guide injection strategies or optimising protocols.¹⁴,¹⁵ In practice, injection protocols vary widely in volumes and flow rates.¹⁶,¹⁷ This heterogeneity reflects the lack of standardisation and presents a twofold challenge. Indeed, practice variability translates into variable patient risk, including contrast-induced nephropathy (CIN), allergic or hypersensitivity reactions, injection discomfort, and, in rare cases, rupture of small vessels or aneurysms caused by injection pressure.¹⁸,¹⁹ Furthermore, it complicates clinical research and study comparability.

Management of these injection parameters is a shared responsibility within the operating team including interventional neuroradiologists and radiographers, working in close partnership to ensure both technical execution and clinical safety. Radiographers play a central role in setting up the power injector, real-time monitoring, and practical adaptation to patient-specific characteristics. Optimising and harmonising practices thus require this medical-technical collaboration, with the aim of moving towards a reasoned practice enabling the volumes and flow rates of ICM administration to be limited while ensuring optimal diagnostic image quality.

This narrative review aims to explore current practices and highlight the variability in ICM injection parameters for diagnostic cerebral angiography in the evaluation of intracranial aneurysms, emphasising the lack of standardised protocols and their impact on patient safety and image quality.

## Literature search

A focused literature search was conducted to identify publications addressing ICM injection protocols in diagnostic cerebral angiography, with a particular emphasis on the evaluation of intracranial aneurysms. Google Scholar was queried using combinations of terms, including "cerebral angiography", "cervicocerebral catheter angiography", "intracranial aneurysm", "iodinated contrast media", "contrast injection", "injection volume", "injection rate", "angiographic technique", "interventional neuroradiology", "DSA" and "3D RA". The search covered articles published from January 2000 to June 2025, and included only publications available in English, either originally written or translated. Given the

absence of specific recommendations, all publication types were considered, including original research, reviews, technical notes, guidelines and editorials. Additional sources were extracted from the reference lists of relevant articles when available. Papers were included if they addressed technical aspects of ICM injection in diagnostic cerebral angiography, encompassing volumes, flow rates, or optimisation strategies. Articles focusing on CTA or MRA, non-cerebral angiography procedures, or studies involving non-human subjects or phantoms were excluded. A simplified PRISMA-style flow diagram²⁰ summarising the search and selection process is presented in Fig. 1.

## Imaging acquisition in diagnostic cerebral angiography

Diagnostic cerebral angiography for the evaluation of intracranial aneurysms is generally based on the acquisition of 2D and 3D images of the internal carotid and vertebral arteries.²¹ In some cases, common carotid artery can be opacified, particularly to facilitate catheterisation. However, this approach requires higher injection parameters (volume and flow rate) and results in simultaneous opacification of the external carotid circulation, leading to vascular superimposition and consequently reducing analysis quality of the ICA.

### Two-dimensional digital subtraction angiography

2D DSA enables real-time following of ICM injected into a selected artery (ICA or VA), revealing blood flow dynamics through the vessels: arterial phase, tissue impregnation and venous return. It provides both spatial and temporal analysis of the cerebral vascular system opacified.⁴ Anteroposterior and lateral views are systematically performed in order to visualise the opacified vascular network in two orthogonal planes, mitigating the superimposition inherent to planar imaging. Standardised positioning criteria, depending on the injected artery and territory explored (e. g., symmetrical alignment of the head in the longitudinal axis or superimposition of the petrous bones with the orbit base) ensure optimal visualisation of the vascular network and reproducibility of images both for the same patient and between different procedures.

### Three-dimensional rotational angiography

3D RA involves multiple 2D projections around the volume of interest, by C-arm rotation, performed during an ICM injection into a selected artery.²² While 2D imaging provides real-time analysis of blood flow dynamics, volumetric acquisition is limited to a strict arterial phase. The acquired 2D projections are then computer-processed to generate a working volume, and various interactive reconstruction and post-processing tools are used for analysis: volume rendering (VR), multiplanar reconstructions (MPR) or maximal intensity projection (MIP).²³ By overcoming the superimposition limitations inherent to 2D imaging, 3D RA has become an essential tool, significantly improving diagnosis accuracy, lesion identification and intervention planning in INR.

## Injection parameters and iodinated contrast media management

In diagnostic cerebral angiography, two types of intra-arterial ICM injections are performed: hand injections and those using a power injector. Hand injections are performed by the operator using a syringe connected to the catheter during catheterisation phases, under fluoroscopic guidance. Low in volume and randomly
<figure><img src="image_3.png" /><figcaption>**Figure 1.** Simplified PRISMA-style flow diagram.</figcaption></figure>

performed, they facilitate navigation to the supra-aortic arteries and are used to confirm the position of the catheter before any diagnostic acquisition. In contrast, injections using a power injector are controlled by the radiographer during angiographic acquisitions (2D DSA or 3D RA). The flow rates and volumes are precisely managed, ensuring homogeneous and reproducible opacification of the vascular region being examined. These injections, which are quantifiable and highly standardisable, are the focus of this study. All subsequent discussions on injection parameters refer to administration using a power injector.

Iodinated contrast media is essential to opacify vascular structures and enable a detailed analysis of cerebral circulation. However, the use of this type of medication is not risk-free,²⁴,²⁵

requiring optimised management of injection parameters in order to balance diagnostic effectiveness and patient safety.

**Injection volume:** in millilitres (mL), it is determined according to the artery examined (ICA or VA) and the type of acquisition (2D DSA or 3D RA). Sufficient volumes are required to ensure homogeneous opacification of target vascular territories. However, the cumulative volume administered during a procedure can quickly become significant. As the risk of contrast-induced nephropathy is directly correlated with the total dose injected, rigorous management is essential in order to limit this parameter as much as possible.²⁶,²⁷

**Injection flow rate:** in millilitres per second (mL/s), it is also determined by the vessel being examined. To ensure optimal opacification of the vascular system, sufficient flow rates are
required to ensure a compact and homogeneous ICM bolus and prevent early dilution in the bloodstream. However, higher flow rates increase the likelihood of vascular hypersensitivity reactions, most often associated with hot flushes, nausea and headaches.²⁸ The discomfort caused by ICM injections can sometimes lead to involuntary movements of the patient's head, resulting in motion artefacts which can affect image quality, sometimes requiring re-imaging, which involves additional injection as well as increased radiation exposure.

**Pressure:** in pounds per square inch (PSI), it depends on the volume and injection flow rate, but also on the viscosity of the ICM and the vascular resistance at the tip of the catheter. Many power injectors allow the operator to set a maximum pressure threshold to prevent exceeding set limits, which can help reduce the risk of vascular injury and improve patient tolerance.

Iodinated contrast media are available in different concentrations on the market, ranging from 250 to 400 mgl/mL. In most INR centres, a single medication is commonly used to simplify logistics and standardise practices. While higher concentrations increase vascular opacification, they also increase the iodine load (in mgl) for the same injected volume, which may increase the risk of contrast-induced nephropathy. Therefore, the concentration of ICM should be considered in conjunction with the injection parameters (volume, flow rate), with an overall goal of minimising total iodine exposure while maintaining diagnostic image quality.

Other factors, such as ICM viscosity, catheter size, or access site location (radial or femoral), may also influence bolus quality and vessels opacification on images. These aspects are recognised but are beyond the scope of this study.

## Current practices and variability

To date, no national or international recommendations exist to guide the choice of ICM injection parameters in diagnostic cerebral angiography. In absence of a clear framework, practices vary significantly between INR centres and sometimes even among operators, following protocols based on local habits and empirical considerations.¹⁶ Furthermore, beyond the heterogeneity of

practices, the lack of specific recommendations makes it difficult to contextualise individual practices. In this context, the natural tendency is to adopt high injection volumes and flow rates in order to obtain maximum angiographic contrast, even if the clinical impact remains to be clarified.

Although published data are limited, the literature provides a few insights into current injection practices.²⁰,²⁹,³⁰ In 2D DSA of the ICA, injection volumes commonly range from 5.0 to 10.0 mL with flow rates between 3.0 and 7.0 mL/s.³¹,³² VA images are acquired with volumes between 4.5 and 8.0 mL, and with flow rates of 2.5–5.0 mL/s.³³,¹⁷ For 3D RA, ACI imaging is performed using injection volumes ranging from 10.0 to 36.0 mL with flow rates of 1.5–5.0 mL/s.³⁴,³⁵ VA 3D RA acquisitions are conducted with volumes between 10.0 and 24.0 mL, and flow rates of 2.0–5.0 mL/s.³⁶,³⁷ The full set of parameters extracted from the literature is presented in Table 1, highlighting the variability across studies and centres.

Technical factors also influence practice. The type of imaging system (monoplane or biplane) directly affects the number of injections required: biplane systems allow simultaneous acquisition of anteroposterior and lateral projections, reducing the ICM volume needed for 2D DSA compared to a monoplane system, which requires an injection for each projection. In addition, the generation and quality of imaging equipment, particularly the detection system, affect the sensitivity of contrast detection, and consequently, image quality. Acquisition protocols and settings must also be considered, as suboptimal parameters can reduce contrast visibility, indirectly influencing the choice of injection parameters to achieve sufficient vessel opacification.

Recent advances in artificial intelligence (AI) are increasingly integrated into INR, focusing particularly on radiation exposure reduction through deep learning-based reconstruction algorithms³⁸ and noise reduction techniques. These approaches demonstrate that AI can adapt image acquisition parameters in real time to maintain diagnostic quality while reducing radiation dose to the patient. By extension, similar AI-based methods could be applied in the future to ICM injection protocols, enabling real-time optimisation of volume, flow rate and pressure, based on

<table><caption>**Table 1**
Injection volumes and flow rates of ICM in cerebral catheter angiography: summary of reported practices in literature.</caption><thead><tr><th>Artery</th><th>Modality</th><th>Volume (mL)</th><th>Flow rate (mL/s)</th><th>Source</th></tr></thead><tbody><tr><td>ICA</td><td>2D</td><td>8</td><td>6</td><td>Yousem DM, Trinh BC. Am J Neuroradiol. 2001; 22(10):1838-40</td></tr><tr><td>ICA</td><td>2D</td><td>10</td><td>6-7</td><td>Singh DK et al. Neurol India. 2023; 71(1):31-34</td></tr><tr><td>ICA</td><td>2D</td><td>8-10</td><td>NR</td><td>Van Rooij WJ et al. Am J Neuroradiol. 2008; 29(5):976-9</td></tr><tr><td>ICA</td><td>2D</td><td>5</td><td>3</td><td>Kitazawa K et al. J Neurointerv Surg. 2013; 5(3):253-7</td></tr><tr><td>ICA</td><td>2D</td><td>9-10</td><td>4-5</td><td>Sugahara T et al. Am J Neuroradiol. 2002; 23(9):1545-52</td></tr><tr><td>VA</td><td>2D</td><td>8</td><td>5</td><td>Yousem DM, Trinh BC. Am J Neuroradiol. 2001; 22(10):1838-40</td></tr><tr><td>VA</td><td>2D</td><td>8</td><td>3-5</td><td>Singh DK et al. Neurol India. 2023; 71(1):31-34</td></tr><tr><td>VA</td><td>2D</td><td>8-10</td><td>NR</td><td>Van Rooij WJ et al. Am J Neuroradiol. 2008; 29(5):976-9</td></tr><tr><td>VA</td><td>2D</td><td>4.5</td><td>2.5</td><td>Kitazawa K et al. J Neurointerv Surg. 2013; 5(3):253-7</td></tr><tr><td>ICA</td><td>2D</td><td>15</td><td>3</td><td>Sugahara T et al. Am J Neuroradiol. 2002; 23(9):1545-52</td></tr><tr><td>ICA</td><td>3D</td><td>10-15</td><td>2-3</td><td>Ki HJ et al. Korean J Radiol. 2022; 23(2):256-263</td></tr><tr><td>ICA</td><td>3D</td><td>18-24</td><td>3-4</td><td>Van Rooij WJ et al. Am J Neuroradiol. 2008; 29(5):976-9</td></tr><tr><td>ICA</td><td>3D</td><td>21-36</td><td>3-5</td><td>Takagi S et al. J Belg Soc Radiol. 2018; 102(1):76</td></tr><tr><td>ICA</td><td>3D</td><td>20</td><td>3</td><td>Lescher S et al. J Neurointerv Surg. 2016; 8:1061-1066</td></tr><tr><td>ICA</td><td>3D</td><td>15</td><td>2.5</td><td>Kitazawa K et al. J Neurointerv Surg. 2013; 5(3):253-7</td></tr><tr><td>ICA</td><td>3D</td><td>10-18</td><td>1.5-3</td><td>Gao Z et al. Interv Neuroradiol. 2016 Jun; 22(3):287-92</td></tr><tr><td>ICA</td><td>3D</td><td>NR</td><td>4-5</td><td>Ishihara S et al. Interv Neuroradiol. 2000 Jun 30; 6(2):85-94</td></tr><tr><td>ICA</td><td>3D</td><td>16</td><td>4</td><td>Brinjikji W et al. Am J Neuroradiol. 2009; 30(4):831-4</td></tr><tr><td>VA</td><td>3D</td><td>10-15</td><td>2-3</td><td>Ki HJ et al. Korean J Radiol. 2022; 23(2):256-263</td></tr><tr><td>VA</td><td>3D</td><td>18-24</td><td>3-4</td><td>Van Rooij WJ et al. Am J Neuroradiol. 2008; 29(5):976-9</td></tr><tr><td>VA</td><td>3D</td><td>15</td><td>2.5</td><td>Kitazawa K et al. J Neurointerv Surg. 2013; 5(3):253-7</td></tr><tr><td>VA</td><td>3D</td><td>NR</td><td>4-5</td><td>Ishihara S et al. Interv Neuroradiol. 2000 Jun 30; 6(2):85-94</td></tr><tr><td>VA</td><td>3D</td><td>16</td><td>4</td><td>Brinjikji W et al. Am J Neuroradiol. 2009; 30(4):831-4</td></tr><tr><td>VA</td><td>3D</td><td>15</td><td>3</td><td>Sugahara T et al. Am J Neuroradiol. 2002; 23(9):1545-52</td></tr></tbody></table>

NR = non reported.
specific patient characteristics (e.g., vessel diameter, blood pressure, heart rate or age). Such developments would be consistent with the ALADA principle and represent a promising area for future research and optimisation of clinical practice in interventional neuroradiology.

## Rationale for optimisation and medico-technical considerations

Optimising ICM injection parameters in cerebral angiography is crucial, as it directly impacts three major aspects of care: patient safety, comfort and diagnostic reliability. By adjusting the volume injected per acquisition, cumulative iodine exposure can be limited, leading to a reduced risk of contrast-induced nephropathy. Lowering the flow rate may decrease vascular hypersensitivity and discomfort during the procedure, improving overall tolerance and enhancing patient experience.

The goal of medical imaging is not to produce the most highly contrasted image possible (aesthetic criteria), but to provide a precise answer to a clinical question with the minimum radiation dose and ICM required. Careful optimisation of injection parameters would therefore limit exposure to ICM while ensuring exploitable results. Significant variability in ICM injection volumes and flow rates between centres strongly suggests that optimisation is feasible without compromising diagnostic performance, and that local practices could be improved through standardisation based on objective benchmarks.

Such efforts require the expertise and shared responsibility of the team, comprising the neuroradiologist and radiographer, whose careful coordination ensures patient safety, comfort, and optimal image quality.³⁹ In daily practice, this collaborative medico-technical approach is essential for achieving consistent and reliable results in diagnostic cerebral angiography.

## Future strategies and perspectives

Current data on ICM injection parameters in cerebral angiography remain limited, with only a few studies addressing this issue and no specific recommendations from scientific societies available to date. Although the ACR-ASNR-SIR-SNIS, CIRSE and ESUR documents¹,¹⁴,¹⁵ provide general recommendations for conducting safe procedures involving ICM injections, they do not include quantitative recommendations regarding injection parameters to guide clinical decision-making, which largely explains the current heterogeneity of practices.

There is therefore an urgent need to extend the ALADA principle to ICM administration in cerebral angiography. Establishing quantitative reference values could guide the selection of injection parameters by operators (radiographers and neuroradiologists), according to the vascular territory explored (ICA or VA) and the imaging technique used (2D or 3D). To address this challenge, a dual strategy should be considered.

Prospective studies could evaluate different ICM injection strategies and their impact on image quality and patient tolerance. Single-centre pilot studies, designed to minimise biases related to differences in imaging equipment, power injectors and ICM nature, could then be extended to multicentre models to ensure that findings are generalisable across different INR centres, thereby strengthening their scientific robustness. These studies should also monitor patient- and procedure-specific factors, such as age, blood pressure, heart rate, vascular access, and catheter type, to better understand their influence on optimal injection parameters.

In parallel, large-scale observational studies could be carried out to collect current practices in several centres, thereby providing a comprehensive and realistic overview of actual clinical

variability. Based on these data, reference ranges could be established – analogous to Diagnostic Reference Levels (DRLs) in radiation protection⁴⁰ – in order to propose new recommendations such as “iodinated contrast media DRLs” which could serve as practical benchmarks for the safe and effective use of ICM.

Combining both approaches would allow real-world practices and prospective findings to mutually enrich each other, supporting the development of harmonised, evidence-based recommendations. Professional consensus, including scientific societies and multidisciplinary working groups, will be essential to promote safer, more consistent and patient centred practices, with radiographers playing a key role in the implementation and technical standardisation.⁴¹,⁴²

Although this study focuses on diagnostic cerebral angiography for the assessment of intracranial aneurysms, a common and reproducible context, optimisation of injection parameters could be applied to other indications, including INR and peripheral vascular radiology, where similar challenges exist.

## Conclusion

Optimising injection parameters in diagnostic cerebral angiography is a priority for advancing safer and more effective practices in INR. The application of ALADA principle – balancing risk management with diagnostic requirement – to ICM, currently unexplored, could reduce its exposure while maintaining diagnostic-quality images. There is an urgent need for clear, specific guidelines defining reference parameters according to vascular territory (ICA or VA) and imaging technique (2D DSA or 3D RA). Radiographers will play a central role in this context, contributing to protocol standardisation, monitoring injections, and ensuring patient safety and comfort. Close collaboration with neuroradiologists is key to implementing optimised practices effectively. Professional consensus and multidisciplinary work will be critical to develop harmonised, evidence based and patient-centred recommendations.

## Ethics approval and consent to participate

Not applicable: Narrative review.

## Availability of data

Data required for this study may be made available by the corresponding author upon reasonable request.

## Author contributions

**ND:** Conceptualization, Methodology, Investigation, Writing – Original Draft.

**JPD:** Supervision, Writing – Review & Editing.

**RP:** Supervision.

**AH:** Supervision.

**LB:** Writing – Review & Editing.

**ILL:** Supervision, Writing – Review & Editing.

## Generative AI use

The authors minimally used the online DeepL Write AI tool, to improve the clarity and fluency of the English text. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.
Funding

This rese was supported by a grant from the French Ministry
of Health (PHRIP-24-0051).

Conflict of interest statement

None.

Acknowledgements

Not applicable.

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