Anatomy of the Le Fort I segment: Are arterial variations a potential risk factor for avascular bone necrosis in Le Fort I osteotomies?

作者：Bruneder Simon^*; Wallner Juergen; Weiglein Andreas; Kmecova Ludmila; Egger Jan; Pilsl Ulrike; Zemann Wolfgang

来源：Journal of Cranio-Maxillofacial Surgery, 2018, 46(8): 1285-1295.

DOI：10.1016/j.jcms.2018.04.023

• Le Fort I segment
• Le Fort I anatomy
• Le Fort I osteomy
• Blood supply
• Avascular bone necrosis
• Arterial variations

Purpose: Osteotomies of the Le Fort I segment are routine operations with low complication rates. Ischemic complications are rare, but can have severe consequences that may lead to avascular bone necrosis of the Le Fort I segment. Therefore the aim of this study was to investigate the blood supply and special arterial variants of the Le Fort I segment responsible for arterial hypoperfusion or ischemic avascular necrosis after surgery.
Material and methods: The arterial anatomy of the Le Fort I segment's blood supply using 30 halved human cadaver head specimens was analyzed after complete dissection until the submicroscopic level. In all specimens the arterial variants of the Le Fort I segment and also the arterial diameters measured at two points were evaluated.
Results: The typical known vascularization pattern was apparent in 90% of all specimens, in which the ascending palatine (D1: 1,2 mm +/- 0,34 mm; D2: 0,8 mm +/- 0,34 mm) and ascending pharyngeal artery (D1: 1,3 mm +/- 0,58 mm; D2: <0,4 mm) were both supplying the Le Fort I segment. However in 10% of all specimens, the Le Fort I segment was dependent on the ascending pharyngeal artery alone and the missing ascending palatine artery was replaced with the anterior branch of the ascending pharyngeal artery (D1: 1,9 mm +/- 0,32; D2: 1,0 mm +/- 0,3 mm).
Conclusion: This study is the first description of a special type of arterial variation of the Le Fort I segment. The type of this arterial variation, its clinical relevance and potential consequences are explained. Individuals with this special arterial anatomy may clinically be at a high risk for hypoperfusion and avascular segment necrosis after surgery. An individualized operation plan may prevent ischemic complications in at-risk patients.

• 出版日期2018-8