Objective

2

To measure the distance from the surface of Fengfu

（GV 16） to the deep important bony structures in children aged 4 to 8 years based on CT three-dimensional reconstruction technology， thereby providing imaging reference data for clinical acupuncture safe operations in terms of different age groups and needle insertion angles.

Methods

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Cervical CT image data were collected from healthy children aged 4 to 8 years with five age groups （4-， 5-， 6-， 7-， 8-year-old groups）， 20 cases in each group. The im

ages were imported into Mimics 21.0 software for three-dimensional reconstruction. The straight-line distances from the skin model surface of the Fengfu

（GV 16） to the first underlying bony barrier （such as the lower edge of the occipital bone， the posterior arch of the atlas vertebra） were measured at intervals of 5° on both the transverse section （0° ± 35°） and the sagittal section （40° upward to 40° downward on the diagonal）. The correlation between the measured distance， age， and angle was analyzed.

Results

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In the transverse and sagittal sections， the measured distance from the skin surface to the underlying bone of Fengfu

（GV 16） at each angle increased with age. In the transverse section， the increase was relatively small within the 0° to 20° angle range， whereas a more pronounced increase was observed when the angle exceeded 20°； at measurement angles of 30° to 35°， the distance of the skin surface to the bone at Fengfu

（GV 16） in the 7- and 8-year-old groups was significantly greater than that in the 4-year-old group （

P

＜0.05）. In the sagittal section， the measured distance from the skin surface to the bone at Fengfu

（GV 16） was shortest and changed greatly at oblique upward angles of 15° to 40° within each age group， and increased markedly at near-vertical angles of 0° to 10°； it was longest at oblique downward angles of -40° to -5° and showed relatively gradual changes.

Conclusion

2

This study obtained the imaging distance data from Fengfu

（GV 16） to the surrounding bony structures in children aged 4 to 8 years through three-dimensional modeling， finding that this distance has clear age and angle dependence， which can provide quantitative evidence for developing individualized and precise safe acupuncture schemes at Fengfu

（GV 16） in pediatric clinical practice.