Longitudinal Analysis of Infraorbital Aging Over a 15-Year Period: An MRI-Based Study in Asian Subjects.

Background: Palpebral bags are commonly managed with infraorbital fat excision during lower blepharoplasty. This surgical approach is based on the assumption of age-related anterior herniation of infraorbital fat. However, controversy remains regarding the true volumetric changes of infraorbital fat with aging.

Objectives: This study aimed to investigate longitudinal anatomical changes in the infraorbital region.

Methods: A retrospective longitudinal analysis of serial magnetic resonance images from 50 healthy individuals (20 males and 30 females) aged 20-60 years was conducted; the mean interval between scans was 18.3 years. Six parameters were measured at the mid-pupillary level: the vertical height of orbital aperture (VHOA), infraorbital fat protrusion length (IPL), soft tissue thickness at the orbicularis retaining ligament (TORL), Anterior globe protrusion (GP), nasion-sella-orbital rim angle (NSO), and maxillary angle (MA). Statistical analyses evaluated parameter changes and correlations with the follow-up interval.

Results: Significant increases in the VHOA and NSO and decreases in the TORL and MA were observed (p < 0.05), indicating progressive orbital skeletal remodeling and soft tissue thinning. IPL and GP remained unchanged in supine position, suggesting no volumetric change of infraorbital fat or displacement of the globe. Regression analysis confirmed follow-up interval as key predictor of VHOA and NSO changes.

Conclusions: Palpebral bags primarily result from structural changes that contribute to pseudoherniation of infraorbital fat and increased prominence above the tear trough. The volume of infraorbital fat itself remains relatively stable. These findings support a lower blepharoplasty approach that prioritizes correcting structural changes over aggressive fat excision.