Stability of Codman Hakim programmable valve pressure settings during 0.23 T portable magnetic resonance imaging: a prospective observational study

Introduction

The ventriculoperitoneal shunt (VPS) has become the most commonly used treatment for hydrocephalus (1,2). Computed tomography (CT) is commonly used in multiple intracranial imaging sessions to assess hydrocephalus. Although efforts have been made to reduce radiation doses from conventional CT (cCT) scanning equipment (3), repeated CT examination, despite being practical, nonetheless entails cumulative ionizing radiation exposure for patients and staff.

In this context, magnetic resonance imaging (MRI) is the preferred option for monitoring changes in patients with hydrocephalus by virtue of its excellent imaging capabilities for brain tissue and its lack of ionizing radiation. However, when exposed to high-field MRI (1.5/3 T), non-MR-resistant programmable valves, such as the Codman Hakim programmable valve—one of the most commonly used valves in the hydrocephalus management—may undergo unintended changes in pressure setting, requiring trained personnel to conduct postscan reprogramming (4,5). In the study by Shellock et al., exposure of nonmagnetic programmable valves to a 3.0 T static magnetic field and MRI scanning altered the valve pressure settings in 56% and 67% of the devices, respectively (6). Moreover, Zemack et al. reported that MRI exposure could lead to changes in valve pressure settings, with pressure setting variations of up to 50 mmH₂O (4). Such changes may lead to intracranial over- or underdrainage, which may have serious clinical consequences. Previous research has also demonstrated the feasibility of low-field portable MRI (pMRI; 0.064T) in neurologic intensive care unit settings, albeit with a limited field strength (7-10).

A “non-MR-resistant shunt” refers to a programmable shunt valve that lacks shielding against external magnetic fields and is therefore susceptible to MRI-related changes in pressure setting. Against this background, low-field pMRI that does not materially alter the valve pressure setting is clinically desirable for VPS follow-up. The ACUTA Elfin Portable Head and Neck MRI System, designed and developed by RayPlus Medical Technology Co., Ltd., is an integrated and pMRI product that meets the diagnostic and therapeutic requirements of common brain diseases. However, whether 0.23 T pMRI meaningfully affects the pressure setting of the Codman Hakim programmable valve while providing adequate ventricular assessment remains insufficiently determined. This study therefore evaluated the impact of 0.23 T pMRI on Codman Hakim valve pressure settings and assessed its ventricular imaging quality through a comparison of Evans index (EI) values with those of CT. We present this article in accordance with the STROBE reporting checklist (available at https://qims.amegroups.com/article/view/10.21037/qims-2025-673/rc).

Methods

Study setting and participants

This prospective observational study was conducted from September 2022 to September 2023 at Zhujiang Hospital of Southern Medical University (Figure 1) and in accordance with the Declaration of Helsinki and its subsequent amendments. The protocol was approved by the Medical Ethics Committee of Zhujiang Hospital of Southern Medical University (approval No. 2022-KY-290-02) and was registered with the Chinese Clinical Trial Registry (identifier: ChiCTR2300077352). The study focused on patients with hydrocephalus who were admitted to the Department of Neurosurgery for the implantation of the non-MR-resistant Codman Hakim programmable valve. Informed consent was obtained from all patients before 0.23 T pMRI was performed as per the approved protocol. The pMRI was conducted in the ward, in the presence of two neurosurgeons and an engineer trained in valve programming. The engineer was responsible for reprogramming the valve if the pressure setting had changed after imaging to prevent adverse effects. Cranial X-rays were obtained both before and after pMRI to facilitate reading of the valve pressure setting via the indicator scale (4).

Figure 1 Flowchart of the different study phases. In total, 40 pMRI sessions were performed across 20 patients. cCT, conventional computed tomography; EI, Evans index; pMRI, portable magnetic resonance imaging; VPS, ventriculoperitoneal shunt.

The diagnosis of hydrocephalus was confirmed through conventional imaging techniques, including 1.5 T/3 T MRI or CT scans, in combination with typical clinical symptoms. These could include symptoms of acute intracranial hypertension (headaches, nausea, vomiting, and optic papillary edema) and chronic-phase manifestations (visual loss, dementia, unsteady walking, and urinary incontinence) (1,11).

Patients with any of the following conditions were excluded: (I) implanted cardiac pacemakers or defibrillators, intravenous drug pumps, insulin pumps, deep brain stimulators, vagus nerve stimulators, cochlear implants, etc.; (II) administration of continuous extracorporeal membrane oxygenation therapy and presence of cardiopulmonary instability, generalized convulsions, or any condition that could be life-threatening during the MRI; (III) claustrophobia or other psychiatric or psychological disorders; and (IV) pregnant individuals or those planning a pregnancy. As this was an exploratory study, there were no relevant indicators for sample size estimation, and a sample size of 20 cases was set.

The results obtained from the pMRI were compared with the most recent conventional cranial CT imaging results via the EI. The EI is calculated by dividing the widest frontal angular diameter of the lateral ventricle by the widest intracranial diameter (12). This comparison aimed to investigate the impact of pMRI on the patients. To ensure consistency, the conventional cranial CT imaging was required to be performed within 24 hours of the pMRI scan.

Technical and imaging parameters

The MRI examinations were conducted in the ward with an ACUTA Elfin Portable Head-and-Neck MRI System (RayPlus Medical Technology Co., Ltd., Wuhan, China) equipped with an eight-channel head-and-neck combined coil (Figure 2). The magnetic field strength of the system was 0.23 T, the gradient strength was 25 mT/m, and the switching rate was 50 T/m/s.

Figure 2 pMRI in a neurosurgical ward. (A) Live view of pMRI. (B) A tracheally intubated patient being wheeled into the pMRI room. The system was operated adjacent to standard bedside equipment (e.g., ventilator, infusion pump, cardiac monitor, and oxygen tank). pMRI, portable magnetic resonance imaging.

The MRI examinations were performed by a trained MRI technician and a neurosurgeon. The following sequences were acquired in the axial plane: T1-weighted fast spin echo (T1W FSE), T2-weighted FSE (T2W FSE), T1-weighted fluid-attenuated inversion recovery (FLAIR T1W), and T2-weighted FLAIR (FLAIR T2W).

Patient demographics, clinical course characteristics, and routine neuroimaging (cranial CT) performed within 24 hours of the pMRI examination were obtained from the electronic medical records.

Analysis of changes in valve pressure

Before pMRI, X-ray cephalometric imaging was performed in patients implanted with a non-MR-resistant programmable shunt valve (Codman Hakim programmable valve), and the indicator scale was read to obtain a baseline valve pressure setting (4). After pMRI, the pressure setting was read again under the same method. The effect of pMRI on the pressure setting was assessed through comparison of the pre- and post-pMRI pressure settings.

Image analysis

To assess the ability of pMRI in the evaluation of hydrocephalus, images from each pMRI session were reviewed and compared with cranial CT obtained within 24 hours of pMRI. The EI was used as the principal quantitative measure of ventricular size, defined as the ratio of the maximum width of the frontal horns of the lateral ventricles to the maximum internal skull diameter at the same axial level. EI ≥0.30 was considered to indicate ventricular enlargement (12).

EI was determined manually by two independent raters using the picture archiving and communication system (PACS). Both raters (A and B) were neuroradiologists with more than 10 years of professional experience. They measured the EI from CT images and the EI from pMRI images, and the average of their measurements was used as the final result. The pMRI analysis excluded any sequences that were significantly compromised by artifacts resulting from patient movement during the examination. For pMRI, the average EI of all artifact-free sequences was taken as the representative value. Both raters performed their evaluations in a blinded fashion, without knowledge of the patients’ clinical information.

Pretest

To ensure the safety of the study, a pretest was conducted before study initiation. Codman Hakim programmable valves were subjected to pMRI scanning, and any changes in the pressure setting were evaluated after the pMRI scan.

The Codman Hakim programmable valves had 18 pressure settings (30–200 mmH₂O, with increments of 10 mmH₂O). Unimplanted valves were affixed to either side of a circular water phantom, with a range of implantation positions being approximated. The imaging protocol comprised T1W and T2W sequences. Four adult-type and four pediatric-type valves were randomly selected. Each valve was calibrated to a specific pressure setting before undergoing the MRI scan, which was then confirmed radiographically. Postscan, the pressure settings of the shunt valves were reassessed via X-ray imaging, and any deviations from the initial pressure settings were meticulously documented (Figure 3A-3C).

Figure 3 Verification of valve pressure via X-ray. (A) Pre-pMRI scanning, in which X-rays of a valve were acquired. (B) Post-pMRI scanning, in which X-rays of the same valve were acquired. (C) Valve pressure graphic. (D) A valve in pMRI. pMRI, portable magnetic resonance imaging.

The investigation meticulously controlled for variables that could potentially confound the results. Valve pressures were set at 40, 90, 140, or 190 mmH₂O to mitigate the influence of pressure variations. Additionally, to account for the potential effects of implantation positioning, each valve was scanned bilaterally—once on the left and once on the right side of a circular water phantom (Figure 3D). This protocol resulted in each valve undergoing eight scans, culminating in a total of 64 scans.

The pMRI imaging protocols included T1W, T2W, FLAIR T1W, and FLAIR T2W sequences. Nearby hospital equipment, such as intravenous infusion pumps, cardiac monitors, oxygen cylinders, infusion metal stands, and finger pulse oximetry monitors, did not interfere with the normal use of pMRI. Throughout the examination, the operator and clinician were able to enter and exit the wardroom freely without any adverse events or complications.

Statistical analysis

Descriptive statistics are presented as the mean and standard deviation (SD) or as the median and interquartile range (IQR). The Wilcoxon matched-pairs signed-rank test was used to evaluate the stability of pressure settings in unimplanted Codman Hakim programmable valves pre- and post-pMRI. This test was similarly applied to assess the consistency of the shunt valve pressure settings in patients pre- and post-pMRI.

The concordance between pMRI and cCT in the measurement of EI was quantified via intraclass correlation coefficients (ICCs) (two-way mixed effects, absolute agreement, and single measure), along with 95% confidence intervals (CIs) and Bland-Altman analysis (bias was defined as the mean paired difference d¯ with di=EIpMRI,i−EIcCT,i; 95% limits of agreement were calculated as d¯±1.96×SDd, where SDd is the SD of di). The agreement of EI across pMRI sequences (T1W vs. T2W; T2W vs. FLAIR T2W) was assessed with the above-mentioned ICC and Bland-Altman procedures. For between-modality comparisons, the EI per pMRI examination was computed as the average across all artifact-free sequences for that examination. No interrater ICC was calculated because rater A evaluated cCT while rater B evaluated pMRI. All analyses were performed with SPSS version 24.0 (IBM Corp., Armonk, NY, USA). An ICC <0.2 indicated poor agreement; 0.2–0.4, fair; 0.4–0.6, moderate; 0.6–0.8, strong; and 0.8–1.0, very strong. A two-sided P value <0.05 was considered statistically significant.

Results

Patient characteristics and imaging protocol

Intracranial imaging with 0.23 T pMRI was performed in 20 patients with hydrocephalus implanted with Codman Hakim programmable valves, among whom 14 (70%) were female (median age 55.5 years, IQR 28.5–64.75 years) (Table 1). The types of sequences obtained were different due to the different tolerances of each patient: 11 patients were imaged once, 2 patients were imaged twice, 3 patients were imaged three times, and 4 patients were imaged four times. This resulted in a total of 40 imaging sessions.

Across the cohort, etiologies were predominantly related to tumors (35%) and traumatic brain injury (25%), followed by intracerebral hemorrhage (15%) and subarachnoid hemorrhage (15%), with idiopathic/normal-pressure hydrocephalus accounting for 10% of the cases (Table 1).

Stability of Codman Hakim programmable valves after low-field-strength pMRI

In the pretest (unimplanted valves), the pressure setting remained unchanged in 24 of 64 (37.5%) trials. In 33 of 64 (51.6%) cases, there was a ±10 mmH₂O fluctuation (one setting). Notably, in 7 of 64 (10.9%) cases, a pressure increase of 20 mmH₂O was recorded, which in 5 cases occurred at the initial setting of 90 mmH₂O.

The Wilcoxon matched-pairs signed-rank test was used to assess the consistency of valve pressure settings pre- and post-MRI. Analysis of the 64 trials revealed no significant alteration in valve pressure settings attributable to pMRI exposure (P=0.1607) (Figure 4A).

Figure 4 Wilcoxon matched-pair signed-rank test of the pressure setting of unimplanted valves and the pressure setting of valves in participants with hydrocephalus. (A) Analysis of the 64 trials revealed no significant alteration in valve pressure setting attributable to pMRI exposure (P=0.1607). (B,C) No significant pressure setting change was detected for the 32 trials with the valves on the left side (P=0.8312) or those on the right side (P=0.0564). (D,E) Neither adult (P=0.2286) nor pediatric (P=0.4585) valves showed significant pressure setting changes after pMRI. (F) There was no significant change in valve pressure setting after pMRI in 40 imaging sessions in patients with hydrocephalus (P=0.5552). ns: not significant (P>0.05). pMRI, portable magnetic resonance imaging.

The pressure was analyzed separately for each side of the water phantom: no significant pressure setting change was detected in the left-side trials (n=32; P=0.8312) (Figure 4B) or in the right-side trials (n=32) (P=0.0564) (Figure 4C).

In the analysis of pressure stratified by shunt type, no significant pressure setting changes were found for adult valves (P=0.2286) (Figure 4D) or pediatric valves (P=0.4585) (Figure 4E).

Lack of significant changes in pressure of Codman Hakim programmable valves after low-field-strength pMRI

In 30 of the 40 (75.0%) pMRI imaging sessions, the valve pressure setting was completely unchanged. In 10 of the 40 (25.0%) sessions, the pressure setting changed slightly: 5 (12.5%) by ±10 mmH₂O (1 setting) and 5 (12.5%) by ±20 mmH₂O (2 settings). In terms of direction, 6 (15.0%) increased and 4 (10.0%) decreased.

The consistency of the valve pressure setting in implanted patients before and after pMRI was assessed via the Wilcoxon matched-pairs signed-rank test. We found that there was no significant change in valve pressure setting after pMRI across 40 imaging sessions (P=0.5552) (Figures 4F,5).

Figure 5 Bar graph demonstrating the magnitude and direction of changes in valve pressure setting caused by pMRI in 40 cases. pMRI, portable magnetic resonance imaging.

EI analyses

To ascertain the precision of pMRI in comparison to established neuroimaging benchmarks, 16 participants underwent both pMRI and cCT within a 24-hour interval (a comparison of pMRI and cCT is shown in Figure 6). Two participants were omitted from the analysis: one due to a large cranial defect that precluded accurate EI assessment and another due to the pMRI being conducted preoperatively. The final analysis comprised 14 participants and 24 pMRI examinations, each paired with a corresponding head CT performed within the 24-hour threshold. However, two pMRI scans were excluded due to significant motion-induced artifacts, thus reducing the dataset to 22 pMRI examinations (Figure 1).

Figure 6 Comparison of pMRI and cCT in a patient with hydrocephalus due to traumatic brain injury. (A1-A4,B1-B4,C1-C4) The first, second, and third columns show the pMRI T1W, T2W and FLAIR T2W images, respectively. (D1-D4) The fourth column shows the CT images. cCT, conventional computed tomography; CT, computed tomography; FLAIR, fluid-attenuated inversion recovery; pMRI, portable magnetic resonance imaging; T1W, T1-weighted; T2W, T2-weighted.

For the purpose of comparison, EI values were independently evaluated: rater A analyzed the cCT images, while rater B examined the pMRI images. To ensure consistency and mitigate intersequence variability, the EI derived from pMRI was averaged across all applicable sequences for each participant.

The agreement of EI measurements by the two raters was first assessed. ICC analysis showed a high degree of consistency for the EI index of pMRI between the two raters in terms of the ICC (0.999; 95%CI: 0.998–1.000; P<0.001). Similarly, the EI index of cCT assessed by the two raters also showed high consistency as per the ICC (0.998; 95% CI: 0.995–0.999; P<0.001). ICC analysis indicated significant intergroup agreement between pMRI and cCT for EI values (0.981; 95% CI: 0.955–0.992; P<0.001). Thus, pMRI imaging was found to be highly accurate in assessing ventricular enlargement. The median EI for pMRI was 0.2828 (IQR 0.2413–0.3393), while that for cCT was 0.2827 (95%CI: 0.2468–0.3524). The Bland-Altman plot comparing the EI values between pMRI and cCT showed a bias of –0.0019, with the limits of agreement ranging from –0.0283 to 0.0245 (Figure 7A).

Figure 7 Bland-Altman plots of EI. (A) Bland-Altman plots for pMRI and cCT (bias 0.0018; LOA –0.0166 to 0.0202). (B) Bland-Altman plots for the T1W pMRI and T2W pMRI sequences (bias –0.0035; LOA –0.0181 to 0.0111). (C) Bland-Altman plots for T2W pMRI and FLAIR T2W pMRI sequences (bias 0.0043; LOA –0.0120 to 0.0207). Bias and LOA are shown by the dotted lines. cCT, conventional computed tomography; EI, Evans index; FLAIR, fluid-attenuated inversion recovery; LOA, limits of agreement; pMRI, portable magnetic resonance imaging; T1W, T1-weighted; T2W, T2-weighted.

In the dataset of 22 pMRI scans, 15 incorporated both T1W and T2W sequences, while 10 were complemented by both T2W and FLAIR T2W imaging. The concordance of EI across these pMRI sequences was rigorously evaluated via ICC and Bland-Altman analyses. There was significant concordance between the EI of T1W and T2W (ICC =0.995; 95% CI: 0.985–0.998; P<0.001). The Bland-Altman plot of the EI of T1W and T2W showed a bias of –0.0021, with limits of agreement ranging from –0.0162 to 0.0120 (Figure 7B). There was significant agreement between the EI values of T2W and FLAIR T2W (ICC =0.995; 95% CI: 0.982–0.999; P<0.001). The Bland-Altman plot of the EI values of T2W and FLAIR T2W showed a bias of 0.0029, with limits of agreement ranging from –0.0107 to 0.016 (Figure 7C). These findings data indicated that the different sequences of pMRI were consistent with those of cCT accurate, could accurately assess ventricular enlargement, and could thus aid neurosurgeons in determining the condition of patients with hydrocephalus.

Discussion

This study examined bedside low-field (0.23 T) pMRI in its ability to evaluate the ventricular system post-VPS surgery in patients implanted with a Codman Hakim programmable valve. Under these study conditions (with immediate pre-and post-scan assessment), we observed no clinically meaningful alterations in valve pressure settings. Notably, any observed deviations in shunt valve pressure remained within a 20 mmH₂O range, a threshold that does not necessitate emergent recalibration of the valve. This stability in valve performance under the influence of MRI is critical, as it ensures the continuity of patient care without compromising safety. The findings indicate that the use of 0.23 T pMRI is compatible with the presence of a Codman Hakim programmable valve under these conditions, thereby expanding the utility of neuroimaging modalities in patients with implanted cerebrospinal fluid diversion systems.

CT scanning is cost-effective but involves ionizing radiation exposure, particularly when serial imaging is required for postoperative assessment of ventricular dynamics in patients with hydrocephalus. Cumulative exposure to the X-ray radiation inherent to multiple CT sessions escalates the risk of adverse health effects, an issue of particular concern in pediatric patients. Epidemiological data indicate that an incremental radiation dose of 10 mSv correlates with a 0.04% uptick in mortality risk (13). The heightened mitotic activity characteristic of pediatric physiology confers an increased vulnerability to ionizing radiation, with younger children facing a substantially elevated oncogenic risk (14). Specifically, 1-year-old patients may have a tumor mortality risk 10 to 15 times higher than that of adults when exposed to equivalent radiation doses under identical CT imaging conditions (15). Moreover, the lifelong radiation dose continues to accumulate with each subsequent radiologic evaluation. Head CT protocols in many healthcare systems have been optimized to reduce dose, and MR-resistant programmable valves are becoming increasingly available; therefore, the incremental value of pMRI depends on local resources and practice patterns, and we did not perform a cost-effectiveness analysis. In this context, the use Codman Hakim programmable valves followed by serial imaging with low-field-strength pMRI may constitute a valuable strategy for mitigating radiation exposure in hydrocephalus management. This approach not only preserves diagnostic fidelity but also aligns with the imperative of safeguarding patient health, particularly in the pediatric patients, by minimizing the reliance on ionizing radiation-based imaging techniques.

High-field MRI, operating at 1.5–3 T, requires a controlled setting, stringent safety protocols, skilled operators, and often patient relocation to a dedicated imaging suite (16). This process is unnecessary for patients with hydrocephalus who require frequent imaging for routine ventricular size assessment. Moreover, the interaction of high-field MRI with Codman Hakim programmable valves may alter valve pressure settings, necessitating onsite technical intervention for recalibration, which can be inconvenient for both patients and healthcare providers. The deployment of pMRI in the postoperative management of patients with Codman Hakim programmable valves offers a pragmatic solution, potentially diminishing both the economic impact and the logistical complexities related to valve pressure adjustments. This approach aligns with the evolving landscape of patient-centered care in neurosurgery, in which minimizing patient discomfort and streamlining postoperative management are paramount. These findings should not be generalized to other valve models without confirmation via dedicated testing.

When MRI first emerged as an imaging modality for clinical applications, its early iterations were limited to low field strengths in the range of 0.05 to 0.35 T due to the technological limitations of the time (17,18). The limited image quality of these low-field MRI systems hindered their widespread clinical adoption (19). Over the past 40 years, advanced low-field-strength technology has evolved significantly in terms of hardware, magnet design, and gradients, which has enabled low-field-strength MRI to achieve imaging quality comparable to that of the widely used 1.5 T MRI systems (20-24). Recent studies have reported on a highly convenient low-field MRI system; however, with a magnetic field of only 0.06 T, its imaging quality requires further evaluation (7-10).

The MRI apparatus examined in our study features a 0.23 T magnetic field intensity, with capabilities for bedside operation. Notably, the equipment’s operation adjacent to standard bedside equipment—such as ventilators, intravenous pumps, cardiac monitors, dialysis machines, and oxygen tanks—without observed interference in our setting, represents a significant advancement, allowing for seamless integration into various therapeutic settings. Among patients who acquire hydrocephalus from traumatic brain injuries, a portion remain in a prolonged unconsciousness state. The transport of such individuals to conventional imaging facilities heightens the likelihood of damage to the aforementioned medical equipment, compromises venous access, and heightens the risk of accidental endotracheal tube displacement (25,26). pMRI, with its inherent compatibility with nearby ferromagnetic substances, can be brought directly to the patient’s location, thereby significantly mitigating the associated risks.

This study involved several limitations which should be discussed. First, the sample size was relatively small, comprising only 20 patients, which may limit the generalizability of the findings. A larger cohort would be necessary to confirm the stability of Codman Hakim programmable valves across a broader population. Second, the study was conducted in a single center, which might have introduced selection bias and limited the applicability of the results to different clinical settings. Multicenter studies would help validate the findings across a greater diversity of patient populations and healthcare environments. Moreover, our findings apply only to Codman Hakim programmable valves under a 0.23 T pMRI protocol with immediate pre- and post-scan assessment. Third, while the study demonstrated that low-field-strength pMRI had minimal impact on valve pressure settings, follow-up assessments were limited to the immediate postimaging period. Long-term studies are needed to evaluate whether repeated exposure to pMRI affects valve functionality over time. Fourth, image quality was assessed based on comparison with cCT, but a direct comparison with high-field MRI (e.g., 1.5 T or 3 T) was not performed. Future research should examine whether pMRI provides equivalent diagnostic accuracy to that of standard MRI modalities. Finally, although no adverse events were observed, the safety of pMRI in patients with other implanted medical devices, along with the cost-effectiveness of the protocol, remains to be evaluated through further investigation.

Conclusions

Under the specific conditions of this study (0.23 T pMRI, Codman Hakim programmable valve, and immediate pre- and post-scan assessment), we did not observe clinically meaningful changes in valve pressure settings beyond ±20 mmH₂O. pMRI-derived EI values showed excellent agreement with those derived from cCT, supporting pMRI as a bedside adjunct for ventricular assessment after VPS in patients with Codman Hakim valves. These findings should not be generalized to other valve models without dedicate evaluation. Future work should assess the long-term safety of repeated pMRI scans with MR-resistant valves and the cost-effectiveness across care settings, particularly those where bedside imaging, transport risk mitigation, and a radiation minimization are key priorities.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://qims.amegroups.com/article/view/10.21037/qims-2025-673/rc

Data Sharing Statement: Available at https://qims.amegroups.com/article/view/10.21037/qims-2025-673/dss

Funding: This work was supported by Basic and Applied Basic Research Foundation of Guangdong Province (grant No. 2022A1515140149).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-2025-673/coif). All authors report that this work was supported by Basic and Applied Basic Research Foundation of Guangdong Province (grant No. 2022A1515140149). The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by Medical Ethics Committee of Zhujiang Hospital, Southern Medical University (approval No. 2022-KY-290-02) and informed consent was taken from all individual participants.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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