The Posthyaluronidase Syndrome: Dosing Strategies for Hyaluronidase in the Dissolving of Facial Filler and Independent Predictors of Poor Outcomes.

Background: Hyaluronic acid dermal fillers are used extensively in periocular aesthetic medicine, and the incidence of filler-related complications is increasing. This study aimed to investigate the optimal dosing strategy for hyaluronidase and to identify predictors of poor outcomes. Methods: We performed a retrospective review of 157 orbits of 90 patients treated with hyaluronidase over a 4-year period. Demographic data, indication, and details of hyaluronidase treatment and outcomes were recorded. Results: The primary indication for dissolving filler was swelling in 52%, lumpiness in 20%, and before surgical blepharoplasty in 17%. The most frequently used hyaluronidase concentration was 150 U per mL in 66%, followed by 75 U per mL in 31%, 37.5 U per mL in 3%, and 100 U per mL in 1%. Outcomes were characterized as follows: 59% with a satisfactory result; 24% as insufficient treatment requiring further hyaluronidase; and 18% complaining of facial changes such as hollowing, indicating a post hyaluronidase syndrome. There was no statistical difference in outcomes between the 75 and 150 U per mL dosage groups (P = 0.625). A significant correlation was identified between posthyaluronidase syndrome and duration of filler in situ (P = 0.00019) and volume of filler (P = 0.000017). Conclusions: The posthyaluronidase syndrome may be related to previous filler volume and duration, rather than the concentration or dose of hyaluronidase used. All patients should be informed about the risks of adverse effects after hyaluronidase treatment; patients with longer histories of filler use and higher total volumes should be advised of the increased risk.

Tear Trough Filler Using the Three-point Tangent Technique: Lessons from 1452 Tear Trough Applications.

This study describes a novel three-point tangent technique for tear trough filler and the results from the largest series to date. Methods: A retrospective case review was performed for all patients treated between 2016 and 2020. Patient demographics, filler details and complications were recorded. The injection technique involves using a blunt cannula to deliver filler along three linear tangents bespoke to each patient. Results: A total of 1452 applications of filler to the orbits of 583 patients were recorded. The median patient age was 41 years (range 19-77), and 84% were women. The mean volume of applied filler at the first appointment was 0.34 mL to each orbit (range 0.1--1.5); 82% reported no complication, 10% reported swelling with a median duration of 4 weeks (range 1-52), 4.3% experienced bruising, 4.6% reported contour irregularities, and 3.3% experienced a Tyndall effect. Retrobulbar hemorrhage occurred in one patient (0.17%), which was managed immediately with no lasting visual compromise. Volume of filler injected was significantly associated with a risk of edema (P < 0.00001) and contour irregularities (P = 0.012). In total, 50% of cases of edema resolved spontaneously after 4 weeks. Filler was dissolved in 1.9% of orbits. Patients with a history of dissolving were significantly more likely to require dissolving after subsequent reinjection (P = 0.043). Conclusions: The three-point tangent technique is a safe and effective method. Increasing volume of filler administered is associated with complications of edema and contour irregularities. Edema is the most common complication and resolves spontaneously in half of patients by 4 weeks.

Orbital compartment syndrome following tear trough filler injection.

A patient was treated with tear trough filler and developed a retrobulbar haemorrhage. This was managed acutely with a lateral canthotomy and cantholysis with no lasting visual compromise. This is the first reported case of an orbital compartment syndrome following filler injection and highlights the potential blinding complications which can occur. There should be an increased awareness of this complication amongst practitioners administering tear trough filler.

Corneal Neurotization Using the Great Auricular Nerve for Bilateral Congenital Trigeminal Anesthesia.

PURPOSE: The purpose of this study was to describe an indirect corneal neurotization (CN) technique for congenital bilateral trigeminal anesthesia using the greater auricular nerve (GAN) as a donor. METHOD: CN was performed to preserve the integrity of the only seeing eye in a 4-year-old boy with pontine tegmental cap dysplasia and bilateral trigeminal anesthesia. He had recurrent corneal ulceration and scarring despite full medical treatment. The GAN was used as a donor, and the sural nerve was harvested and used as a bridge which was tunneled to the sub-Tenon space in the inferior fornix. The fascicles were distributed into the 4 quadrants and sutured to the sclera near the limbus. RESULT: This technique resulted in providing corneal sensation and improving stability of the epithelium. Corneal opacity gradually decreased allowing significant visual improvement evidenced in the early postoperative months. CONCLUSIONS: Using the GAN technique for CN bypasses trigeminal innervation and has the potential to improve corneal sensation. The GAN is a large caliber nerve and provides a large amount of axons and robust neurotization. This technique would be desirable for cases with bilateral congenital trigeminal anesthesia, such as pontine tegmental cap dysplasia.