Does the Tyndall effect describe the blue hue periodically observed in subdermal hyaluronic acid gel placement?

BACKGROUND: The blue hue of skin overlying injected hyaluronic acid (HA) fillers in certain cases has been hypothesized in the literature as related to the Tyndall effect. This investigation aims to understand the relevant optical concepts and to discuss the plausibility of this assertion. METHODS: Theoretic and physical aspects of relevant optical theories including the Tyndall effect, the Raleigh criterion and the Mie Solution are discussed, with simple examples. The physical properties of the system (both HA and subcutaneous tissue) are explored. Alternate concepts of dermal hue generation are discussed. RESULTS: The Tyndall effect (and Rayleigh criterion) describe optical phenomenon that occur as light passes through colloidal solutions containing uniform spherical particles of sizes less than the length of a wavelength of visible light. HA fillers are complex, large, non-spherical, cross-linked hydrogels, and thus are not well characterized by these theories.Skin is a complex optical surface in which shorter wavelengths of light are selectively filtered at superficial depths. Light passing through to subdermal HA would have low blue light amplitude, minimizing what light could be preferentially scattered. Further, should blue hues be 'generated' subdermally, the same skin filters work in reverse, making the blue light poorly detectable by an external observer. CONCLUSIONS: The Tyndall effect is unlikely to cause dermal hue changes in HA filler instillation. Optical and perceptual processes explaining superficial vein coloration may better describe subdermal HA hue changes. Vein coloration is thought to be related to three processes: the reflective properties of the skin, the absorptive properties of blood and the perceptive properties of an observer's eyes. Subdermal HA may simulate these phenomena by a number of undetermined, yet plausible mechanisms.

Hyaluronic acid gel distribution pattern in periocular area with high-resolution ultrasound imaging.

BACKGROUND: High-resolution ultrasound (HRUS) is a useful tool in defining anatomic and dynamic soft tissue relationships in the periocular area. It also allows visualization of hyaluronic acid (HA) gel within the soft tissue. OBJECTIVES: The authors investigate the difference in the distribution pattern between 2 HA fillers in the periocular tissue using HRUS. METHODS: The charts of 10 patients who underwent periocular injection using HA gel filler and were subsequently examined with HRUS were reviewed. Half of the patients (n = 5) were treated with Restylane-L (Medicis Aesthetics, Inc, Scottsdale, Arizona) and the remaining 5 with Belotero Balance (Merz Aesthetics, Inc, San Mateo, California). Ultrasonographic evaluation (Logiq p6; GE Healthcare, Waukesha, Washington) was performed before and immediately after HA filler injection. RESULTS: The HA appears as a hypoechoic image within the soft tissue plane on HRUS. Restylane-L filler formed a localized hypoechoic image within the tissue, with some spread into bubbles or pearl-like configuration. Belotero Balance spread more widely into the tissue plane and diffused into an elongated or spindle-shaped hypoechoic image. CONCLUSIONS: Our preliminary data suggest that HA gel fillers with differing production technologies show distinct spread and distribution patterns in the periocular tissues on HRUS examination.

Dynamic high-resolution ultrasound in vivo imaging of hyaluronic acid filler injection.

BACKGROUND: High-resolution ultrasound (HRU) imaging is a useful tool to study hyaluronic acid (HA) filler injected in the face. OBJECTIVE: To observe real-time injection of HA using HRU and describe behavior of the gel injection in various anatomic layers and the effect of massage. METHODS: Deep (preperiosteal), intermediate (subdermal), and superficial (dermal) injections of HA were performed in the supraclavicular area under ultrasonography visualization on a healthy volunteer. Videos were obtained during injection and static images at several time points, including during injection, immediately after injection, 5 minutes after massage of the treated area, and at 2 weeks after injection. RESULTS: During injection, dermally injected HA stayed within the dermis, increasing its echogenicity; subdermally injected HA formed multiple anechoic pearls; and preperiosteal HA produced a single anechoic bubble with diffuse margins. No vertical transection of the planes was observed during injection or after massage. Two-week postinjection imaging showed persistence of the varying HA morphology in each plane. CONCLUSIONS: High-resolution ultrasound allows in vivo study of HA injection behavior. HA adopts different morphology within the tissue depending on the density and compliance of the tissues in the plane of injection.

Bilateral corneal perforations and autoproptosis as self-induced manifestations of ocular Munchausen's syndrome.

PURPOSE: To report a patient with bilateral corneal perforations and autoproptosis in a case of ocular Munchausen's syndrome. DESIGN: Case report. PARTICIPANT: A 26-year-old white male referred to the oculoplastics service with one month history of decreased vision bilaterally and painful right eye. Multiple eyelid scars and right corneal opacity were noted. The patient was previously seen at another institution for rapid loss of vision in both eyes. INTERVENTIONS: An orbit decompression among many procedures failed to controlled extreme pain and proptosis. MAIN OUTCOME MEASURES: Resolution of proptosis, stabilization of vision, pain resolution. RESULTS: Three weeks after enucleation of the right eye was offered, patient presented with spontaneous left ruptured globe. After multiple episodes of self-mutilation and infections, both eyes were exenterated. CONCLUSIONS: Munchausen syndrome can be seen with ophthalmic manifestations and should be considered in the differential diagnosis when ocular abnormalities cannot be explained after a thorough evaluation. Recognition of this psychiatric disease is not only important for correct medical diagnosis and treatment, but also essential in protecting the patients from unnecessary invasive and aggressive medical procedures.