Cosmetic Medicine In “Complications After Facial Injections With Permanent Fillers: Important Limitations and Considerations of MRI

In “Complications After Facial Injections With Permanent Fillers: Important Limitations and Considerations of MRI Evaluation,” the authors propose the use of magnetic resonance imaging (MRI) as an investigative tool in the assessment of delayed-onset complications subsequent to injections of permanent fillers. Utilization of this investigative imaging tool is proposed to be helpful in assessing filler-related complications where it is difficult to clinically assess the nature and extent of the complication. The study included 32 patients who underwent a pretreatment MRI evaluation of post–facial filler injection complications. After 13 of 120 site-specific assessments were excluded due to poor image quality, a total of 107 site-specific clinicoradiologic evaluations were obtained. Clinicoradiologic level of agreement was assessed as strong for depots without complications and noninflammatory nodules (85%), as moderate for abscesses (60%), as fair for low-grade inflammations (32%), and as slight for migrations (9%). In 14% of the cases, results from pretreatment MRI were helpful in the treatment decision making. I commend the authors for undertaking this study to evaluate the role of MRI in the treatment of post–permanent filler complications. Such studies do have a role in patient care, but to what extent and at which point in time? Diagnostic studies—based on MRI, computed tomography, high-frequency ultrasound, even scanning electron microscopy—may be utilized for evaluation of post–filler injection complications but only to supplement the treatment plan based on a thorough history and clinical assessment of the patient. The critical issue is whether the high cost of these studies is justified by the information gained. In what percentage of post– filler injection complications is the treatment course altered by the diagnostic study? In addition, from the medicolegal aspect, does “standard of care” necessitate inclusion of a diagnostic test, or may it be based on patient history and clinical assessment alone? As reported by Lowe et al, the overall rate of post–filler injection complications is very low; for example, granuloma rate is 0.01% to 0.1%. The cohort evaluated in this study is a unique subset of filler patients that has a much higher propensity to develop postinjection complications and is not representative of the “general” filler population. In 30 of 32 patients, a highly (4%) cross-linked polyalkylimide gel was injected. As discussed by Lorenc, the postinjection complication rate of nonabsorbable hydrogel polymers is directly related to the degree of cross-linking; therefore, a high complication rate is expected in this cohort. In 14 of 32 patients of the study population, treatment indications were that of combination antiretroviral therapy–induced facial lipoatrophy, where a routinely large volume of filler material is injected during multiple visits. As reported by Nadarajah et al, the incidence of postpolyalkylimide 4% cross-linked gel injections in patients with HIV-related facial lipoatrophy (large-volume injections) is 19%, significantly different from and higher than that observed where a routinely small volume of material is injected. Because of the study group’s several unique characteristics, applying conclusions reached from this cohort to the general filler population may be unfounded. In the article, the authors categorize filler depots into 4 categories: depots without inflammation, depots with inflammation, depots with abscess formation, and depots with migration in relation to documented placement. In practice, a clinically significant abscess is easily identified by the classic signs of abscess formation (pain, erythema, 537296AESXXX10.1177/1090820X14537296Aesthetic Surgery JournalLorenc research-article2014