Arteriovenous malformation (AVM) is defined as a congenital vascular anomaly that shunts blood from arteries to veins with no capillary perfusion. In some rare hereditary diseases, including capillary malformation-arteriovenous malformation (CM-AVM), hereditary hemorrhagic telangiectasia (HHT), PTEN hamartoma-tumor syndrome (PHTS), AVM is generally considered the characteristic clinic presentation. This review primarily focused on the mechanisms of genetic regulation during embryonic vasculature development, genetic mutations in TGF-beta signaling pathway of HHT, PTEN mutations in PHTS and genetic screening of CM-AVM. In addition, current findings in somatic mutations of extracranial AVM were discussed as well. This review aimed to provide insight into the etiology to help the diagnosis and treatment of extracranial AVM in clinic.

Objective: To explore and evaluate the approach of fat repositioning into premaxillary and prezygomatic spaces combined with intraoral fixation in transconjunctival lower blepharoplasty. Methods: 17 patients (2 males and 15 females) who underwent this approach from Aug, 2018 to Feb, 2019 were reviewed. Their average age was 36.88±8.80 years old (range, 24 to 55 years old). A 1.0-1.5 cm transverse transconjunctival incision was made. After blunt dissection of premaxillary and prezygomatic spaces, orbital fat were released and sutured with 1-2 absorbable sutures. Via the guidance of astraight needle through the a forementioned spaces, a small incision was made at the upper vestibular labial side. The orbital fat was pulled down according to the consensus between surgeon and patient and fixed upon the small intraoral incision. All incisions didn′t need to be sutured. Results: The mean follow up was 3.53±1.71 months (range, 1 to 6 months), transconjunctival and intraoral incisons healed well. Palpebral bags and tear trough deformity were obviously improved. Postoperatively, 2 patients felt a transient tractive feeling in the midface region 1 week after surgery, which spontaneously recovered within 1 to 2 weeks. One patient had red, swollen and painful skin beside the right nasal alar one month after the operation, and the symptoms disappeared after 3-day intravenous infusion of cefradine. No lower eyelid retraction, ectropion, hematoma and other complications were observed. Conclusions This novel approach can achieve periorbital rejuvenation and improve the contour of the lower eyelid and mid-face for patients of all the ages with eyelid bags, tear trough deformity, and midfacial depression, but without severe skin laxity.