๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
Calcium hydroxyapatite
Calcium hydroxyapatite
Calcium hydroxyapatite has been marketed in the United States under the name Radiesse since 2006. It is a semi-solid suspension of 25- to 45-ยตm calcium hydroxyapatite microspheres in a gel carrier of sterile water, glycerin, and sodium carboxymethylcellulose. The primary mineral component of these spheres is the same as the calcium phosphate in bone and teeth, so the filler is biocompatible with low risk of allergic reaction. Mechanistically, new collagen forms over the calcium hydroxyapatite framework and replaces the carrier solution. These effects have been documented histologically for nearly 20 months, although clinical results beyond 12 months are less clear.7
On-label applications of Radiesse include correction of: (1) moderate to severe facial folds and wrinkles such as the nasolabial folds (2) lipoatrophy associated with HIV; and (3) volume loss of the dorsal hands, an often overlooked area that shares the same photo- and age-related volume changes as the face.27,30,31 Facial revolumizing in immunocompetent patients is an off-label indication.7,32 (Fig. 58-8); Radiesse should be injected at the dermal subcutaneous junction or over periosteum. Results are immediate, with correction persisting for about 12 months. It should not be used for lip augmentation due to the risk of granuloma formation and with care around the mouth, where constant contraction of the orbicularis oris during phonation may lead to migration and beading of the filler.32 Because of substantial pain and throbbing after injection, the FDA allows for premixing of Radiesse with 2% lidocaine before treatment.
Of note, patients should understand that while Radiesse is radio-opaque and may be visible on radiographs, CT scans, and mammograms, the filler has not been shown to limit interpretation or obscure findings.33
Figure 58-8. Treatment with Radiesse at the nasolabial folds (baseline A, after B) and midface (baseline C, after D) in immunocompetent patients.