Fundamental Basis of Scalp Layering Techniques to Protect Against Wound Infection: A Comparative Study Between Conventional and In-to-Out Dissection of the Superficial Temporal Artery.

Background: Superficial temporal artery (STA) to middle cerebral artery (MCA) bypass is associated with several surgical problems. Despite the vascular patency and hemodynamic changes after the anastomosis, wound problems can be a major surgical complication.

Methods: In a review of 41 surgical cases of STA-MCA bypass for moyamoya disease or cerebral occlusive vascular disease, we compared the conventional (out-to-in) dissection method for STA (n = 23) with the in-to-out (ITO) dissection method (n = 18) and evaluated the surgical results with respect to wound problems.

Results: The incidence of skin maceration was significantly higher in the conventional dissection group than the ITO dissection group (34.8% vs. 5.5%; P < 0.01). Skin necrosis also showed a higher incidence in the conventional dissection group (39.1%) than the ITO group (22.2%).

Conclusions: These data suggest that the simple layering technique of the ITO dissection method can protect against contamination from bacteria and reduce postoperative surgical wound problems. Sealing of the galea aponeurotica (first protective barrier), including fibrous septa and loose areolar tissues, including the periosteal layer (second protective barrier), is an important factor to decrease the rate of scalp wound infection.