Age-Related Variation in Superficial Temporal Artery in Pediatric Patients

Introduction: The size of the superficial temporal artery (STA) is a key consideration for pediatric and adult patients requiring intracranial perfusion augmentation. For symptomatic pediatric patients with moyamoya disease or arteriopathies, bypass procedures are considered. In addition to timing for restoration of flow, STA caliber may contribute to choice of revascularization procedure. In this study, we aim to characterize the maturation and growth of the STA from infancy to adulthood. Methods: A single-institution retrospective analysis was conducted to identify pediatric and adult patients with either high-resolution magnetic resonance angiography (MRA) or computed tomography angiography (CTA) of the head. Six patient age groups were included: category 1: 0–3 years old (y.o.); 2: 4–7 years.o; 3: 8–11 years.o; 4: 12–15 years.o; 5: 16–18 years.o, and 6: >18 years.o. For each patient, both the left and right STAs were included in analysis. The diameter of the STA was measured at the following three segments: the main branch at the level of zygoma, the frontal branch at the level of the orbital roof, and the parietal branch at the level of the orbital roof. Results: A total of 120 STAs from 60 patients were included, with 10 patients in each age category. The average ages (y.o.) of categories one through six were 1.3 ± 0.82, 5.5 ± 0.97, 9.2 ±1.2, 13±0.88, 16.6 ±0.84, and 29.7 ±2.6, respectively. The average main branch STA diameters (mm) for categories one through six were 2.0 ± 0.47, 2.7 ± 0.50, 2.6 ± 0.34, 2.5 ± 0.39, 2.7 ± 0.33, and 2.6 ± 0.33, respectively. The average frontal branch STA diameters (mm) for categories one through six were 1.6 ± 0.53, 2.4 ± 0.70, 2.3 ± 0.39, 2.2 ± 0.20, 2.4 ± 0.3, 2.3 ± 0.39, respectively. The average parietal branch STA diameters (mm) for categories one through six were 1.5 ± 0.57, 2.2 ± 0.45, 2.3 ± 0.46, 2.2 ± 0.59, 2.0 ± 0.63, 2.1 ± 0.30, respectively. A one-way ANOVA showed significant differences in vessel size across age groups for all three STA segments: main branch ( p < 0.0001), frontal branch ( p < 0.0001), and parietal branch ( p < 0.0001). Post-hoc Tukey tests confirmed that children aged 0–3 years had significantly smaller STA diameters compared with all other age groups ( p < 0.001). Conclusion: Overall, across measurements of all age groups, the STA likely grows in diameter in the first three to four years of life. After this timeframe, the STA sizes were not significantly different from young age to adulthood, thus appearing to reach its maximum diameter early in age. In conclusion, understanding the growth interval of the STA can assist with operative planning for pediatric patients with vascular pathologies requiring STA-MCA bypasses. Publication History Article published online: 27 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany