E2874. The Many Faces of Cosmetic Fillers: A Review of Imaging Features and Pitfalls to Avoid
  1. Samar Naamo; Stony Brook University Hospital
  2. Kush Purohit; Stony Brook University Hospital
  3. Saba Naamo; Geisinger Medical Center
  4. Luv Purohit; Broward Health Medical Center
  5. Sino Mehrmal; St. Louis University
Injectable dermal fillers are gel-like substances used to restore lost volume, soften wrinkles, or enhance facial contours. Increasingly popular, fillers are classically injected in the glabella, lips, perioral region, and superficial buccal fat with less common use in the temples and chin. The composition of these substances typically includes a combination of hyaluronic acid, collagen, and/or calcium hydroxyapatite, leading to heterogeneous imaging features. These findings can mimic trauma, infection, inflammatory changes, or even neoplastic processes. With over 2.6 million injections performed annually, the practicing radiologist should be aware of the range of locations and various imaging characteristics of dermal fillers to ensure accurate diagnosis.

Educational Goals / Teaching Points
The educational goals of this exhibit are to review and describe the multimodality findings for dermal fillers. We will review the facial fat compartments, various types of dermal fillers, and both classic and uncommon injection locations. We will identify the major imaging pitfalls and mimics of fillers. The aim of this exhibit is to display the importance of dermal filler recognition to avoid misdiagnosis and unnecessary intervention.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
The injection of dermal fillers is a common dermatologic procedure to restore lost volume and soften wrinkles. The most common location of cosmetic fillers includes the glabella and lips. Less commonly, injections in the chin and temporal regions may be performed to enhance facial contours and reduce temporal wasting. Most fillers (hyaluronic acid, collagen) demonstrate attenuation and signal patterns reflecting high water content on CT and MRI. In contrast, calcium hydroxyapatite fillers have characteristic linear or clumps of calcification on CT. We will include a pictorial review of CT and MRI findings of hyaluronic acid and collagen fillers in the temporals, lips, and cheeks as well as calcium hydroxyapatite injections in the cheeks and chin. We will also review common mimics such as trauma, cellulitis, and malignancy along with imaging pitfalls for the radiologist to avoid.

Dermal filler injections are increasingly popular cosmetic procedures to restore facial volume and enhance contours. Their atypical and heterogenous imaging features pose a diagnostic dilemma and may mimic trauma, infection, and neoplastic processes. Interpreting radiologists must be familiar with the various imaging findings and locations of dermal filler injections to avoid these imaging pitfalls.