General informationThis section has been translated automatically.
- Since the vascularized scleral flaps are derived from the skin in the immediate vicinity, the elasticity status is important for flap planning. In younger patients with tight skin, much larger flaps than in older people must be prepared to achieve tension-free wound closure (Fig. 1).
- If tumours are located in pre-irradiated areas, this fact must be taken into account, otherwise wound healing disorders must be expected. Surgical errors can occur in the selection of the flap removal site (Fig. 2 a-d), in the positioning and preparation (Fig. 3) of the flap, and in the relocation and implantation. A sufficiently large flap base is required to prevent necrosis. Both the arterial supply of the skin to be transposed and the unhindered venous return flow must be ensured.
- The so-called randomized flaps, in which the length-to-width ratio should not exceed 2.5:1, feed on a branched vascular complex. The vascular supply of axial lobes is assigned to one or two vascular cords. The vascular stem allows a considerable narrowing of the flap base in relation to the flap length. Disregarding the recommended length-width ratio in randomized flaps results in insufficient blood circulation, especially in areas with unfavorable perfusion conditions, such as the back of the hand, sacrum and lumbar region, buttocks or lower legs.
- Total flap necrosis, flap tip or flap edge necrosis are a possible consequence. Necrosis can also occur due to increased mechanogenic tension within the flap. They are caused by increased tension in disproportionate ratios of defect to flap size. Another cause of necrosis is to be found in a faulty skin mobilization technique. When mobilizing the flap, it is essential to avoid kinking the flap in the base area, since otherwise venous congestive oedema may develop. If the blood supply is undirected, there is an indication of incipient necrosis in a lividly discoloured, blood-filled skin, which fades under pressure and whose vessels then quickly fill up again. With increasing congestion and dilatation of the vascular bed, a fading under pressure is less and less obvious. The cyanosis persists and develops a dark olive colour after 24 hours. After 3-4 days, blisters develop which are filled with serum and/or blood. The skin below the blister cover appears moist, cyanotic and without any detectable blood circulation. The process tends to progress, often the final necrosis area is more extensive than initially suspected. After about ten days, a demarcation line with an adjacent inflammatory zone appears. The entire process can be acute and is then resolved within one or two days. Scarred healing of small partial necroses can be expected within a period of two months, provided that the wound is adequately treated. Except for total necrosis or unfavourable localisation, a satisfactory late result is the rule in most cases. Unfavourable localisations in this respect are the face, neck and shoulder region.
- In an axial-pattern flap, the process of flap necrosis occurs in a different way. It generally takes several days for the appearance to fully develop. It is difficult to predict whether the flap will recover. The disturbed area is slightly livid-cyanotic tinged. The symptoms can be completely absent in the early stages. The appearance then remains unchanged for days. The slow manner in which the entire process takes place leaves time for a certain revascularization of the flap edges from the surrounding tissue. The final necrosis area is then limited to an island of tissue.
- Even if the flap is initially well-done intraoperatively, there is a risk of immediate or immediate postoperative complications: oozing bleeding, bacterial infection, shrinkage of the flap. In a certain percentage of cases, corrective follow-up procedures cannot be avoided. In order to correct undesirable postoperative healing results, one should take time and allow about six to eight months to pass. A flap defatting, for example, is indicated after two months at the earliest.
LiteratureThis section has been translated automatically.
- Konz B (1984) Flap plasty: avoidable complications. In: Konz B, Braun-Falco O (ed.) Complications in operative dermatology. Springer, Berlin Heidelberg New York, S. 93-102
- McGregor IA (1987) Plastic surgery. Springer, Berlin Heidelberg New York
- Schulz H (1984) Avoidance of functionally and aesthetically disturbing complications in dermatosurgical operations on the head. In: Konz B, Braun-falco O (Hrsg) Complications in operative dermatology. Springer, Berlin Heidelberg New York, S. 157-162
Prof. Dr. med. Peter Altmeyer
