Mapping of Gluteal Arterial Anatomy with Cone-Beam CT

Abstract

Our comprehension of the vascular anatomy in the gluteal region has yet to meet the increasing demand for precision, especially as plastic surgery techniques continue to advance. Gluteal fat grafting is the gluteoplasty technique of choice of 80% of Brazilian plastic surgeons, as it allows a precise reshaping of the buttocks. However, this procedure has the highest fatality rate among cosmetic procedures, primarily due to the risk of fat embolisms resulting from unintentional injection near damaged gluteal veins. Existing information has so far offered a rudimentary overview of the principal blood vessels within the muscle, derived from MRI and CTA images that lack topographical standardization and a normalized probability distribution. The primary objective of this research was to evaluate the position, size, and regions of heightened vascular density in the gluteal region in relation to anatomical landmarks. The focus was on creating a three-dimensional map, standardized allometrically, to identify zones at a higher risk of fat embolism. In this retrospective cohort analysis conducted at a single center, all patients who underwent cone-beam computed tomography (CBCT) scans of the pelvis between January 2016 and October 2021 were included. A cohort of 32 patients, with an average age of 64 years met the inclusion criteria. Among them, 53% were female, and the average BMI was 24.9 ± 4.6 kg/m². The most common reason for performing CBCT scans was embolization due to bleeding, accounting for 50% of the cases. The median diameter of all gluteal vessels was 1.43 [1.10 – 1.84] mm, consistent with previous CTA findings. The median diameter of the intramuscular gluteal vessels was notably larger than that of the subcutaneous vessels (p<0.001), with a median difference of 0.38 mm. The intramuscular region exhibited significantly higher vascular density compared to the adipose tissue. Additionally, statistically significant variations in vessel diameter were observed, particularly at the iliac fossa and the upper border of the pubic symphysis. Our results lend support to the recommendations of the British Association of Aesthetic Plastic Surgeons (BAAPS), which advocate limiting injections to the subcutaneous layer.