The stylomastoid artery as an anatomical landmark to the facial nerve during parotid surgery: a clinico-anatomic study

BACKGROUND: The identification of the facial nerve can be difficult in a bloody operative field or by an incision that limits exposure; hence anatomical landmarks and adequate operative exposure can aid such identification and preservation. In this clinico-anatomic study, we examined the stylomastoid artery (SMA) and its relation to the facial nerve trunk; the origin of the artery was identified on cadavers and its nature was confirmed histologically. METHODS: The clinical component of the study included prospective reviewing of 100 consecutive routine parotidectomies; while, the anatomical component of the study involved dissecting 50 cadaveric hemifaces. RESULTS: We could consistently identify a supplying vessel, stylomastoid artery, which tends to vary less in position than the facial nerve. Following this vessel, a few millimetres inferiorly and medially, we have gone on to identify the facial nerve trunk, which it supplies, with relative ease. The origin of the stylomastoid artery, in our study, was either from the occipital artery or the posterior auricular artery. CONCLUSION: This anatomical aid, the stylomastoid artery, when supplemented by the other more commonly known anatomical landmarks and intra-operative facial nerve monitoring further reduces the risk of iatrogenic facial nerve damage and operative time

Correlation of cutaneous tension distribution and tissue oxygenation with acute external tissue expansion

Today, the biomechanical fundamentals of skin expansion are based on viscoelastic models of the skin. Although many studies have been conducted in vitro, analyses performed in vivo are rare. Here, we present in vivo measurements of the expansion at the skin surface as well as measurement of the corresponding intracutaneous oxygen partial pressure. In our study the average skin stretching was 24%, with a standard deviation of 11%, excluding age or gender dependency. The measurement of intracutaneous oxygen partial pressure produced strong inter-individual fluctuations, including initial values at the beginning of the measurement, as well as varying individual patient reactions to expansion of the skin. Taken together, we propose that even large defect wounds can be closed successfully using the mass displacement caused by expansion especially in areas where soft, voluminous tissue layers are present