| Skin grafting is a commonly practiced surgical technique for facial superficial defect reconstruction. The advantages of this technique include:easy to perform, high take rate of skin graft, simple post-operative care. But this relatively simple technique has its own inherited drawbacks:propensity of contracture, dryness, concave deformity, pigmentation etc. compared with skin grafting, flap transferring technique have overcome some of these problems. A skin flap differs from skin graft in that the former has the additional subcutaneous tissue and all the skin appendages, while the latter provides only the epidermal layer and partial dermis. A skin flap reconstruction can always yield a more satisfactory clinical outcome for facial defect. There are several kinds of skin flaps, namely local flap, distant flap, free flap, etc. The local flap technique is the simplest one and the most frequently performed one among all these skin flap techniques. Actually it can provide the best cosmetic appearance either. But not all facial defects can readily be repaired with local flaps. In circumstances of large area defect or the vicinity skin tissue lacking mobility, the local flap is always not available. An alternative therapy to local flap technique is free flap method. The superiority of free flaps for head and neck reconstruction has been established in the literature. Although conventional free flaps, such as latissimus dorsi flaps and radial forearm flaps have been workhorse flaps, the donor site morbidity cannot be ignored. With the recent advances in perforator flaps, soft tissue coverage of head and neck defects have shifted from these traditional flaps to perforator flaps, such as anterolateral thigh flaps, to reduce the donor site morbidity. But there are still some problems related to these workhorse perforator flap technique when applying to facial reconstruction:the bulky appearance after reconstruction, lack of optimal recipient vessels especially near the midline zone, the complexity of microsurgery surgery.The original idea of this research comes from the author’s clinical experiences. When harvesting skin graft from groin area for facial reconstruction, the author noticed that there are some perforator vessels just beneath the dermis near the inguinal donor site. So the question comes:if we can repair the facial defect with skin graft from groin area, why cannot we raise an ultra thin free flap from the same donor site instead of the conventional skin graft?I made a search in the Pubmed and found that the groin flap is very popular for soft tissue reconstruction in70’s of last century. But it became out of favor in the following era of muscularcutaneous flap, because of its short, small, and variable vascular pedicle. In2004, the superficial circumflex iliac artery perforator flap was reported by a Japanese surgeon, in which the concept of a perforator flap was incorporated into the groin flap, allowing the aforementioned shortcomings to be overcome. This flap has been applied for reconstruction of the limbs and penis. However, reports of its application for the head and neck region are very limited. Little information can be reached from the literature regarding to the facial reconstruction with superficial circumflex iliac artery perforator flap.This research is set to explore the feasibility of facial reconstruction with superficial circumflex iliac artery perforator flap. Basically three questions should be answered within this research:(1) How to design the superficial circumflex iliac artery perforator flap. Some anatomic features of the perforator vessels should be revealed in the investigation.(2) Which vessel to be anastomosis near facial defect? Do we have other options besides the well-known submandibular incision or preauricular incision? Can we make microsurgical anastomosis near midline area? If we can, then with who?(3) If we can arrived at some conclusion from the part1and part2of these research, so can we applied it to the clinical scenario?In recent years there appeared a new trend in plastic surgery field to investigate the anatomy features of perforator flap with computed tomography angiography technique. It has been proved to precisely locate even tiny vessels with a diameter of0.3mm. I have made use of this technique to help design the DIEP flap and the ALT flap in previous work and I found that anatomic findings with this technique is highly correlated with what I can see during the operation. So I choose the CTA technique, or the so-called digital anatomic visualization technique for the research methods in part1and part2.In part1, Ten pieces of disc with groin area DICOM format data was obtained as the following way:All patients were scanned on one of the16row multidetector CT scanners in Peking Union Medical College Hospital,(GE Healthcare). Scanning range was from10cm above the level of anterior superior iliac spine to3cm below the level of Ischial tuberosity. CT parameters were as follows:helical scanning mode, collimation32×0.625mm for scanner A and64×0.625mm for scanner B,0.984:1helical pitch, rotating time1sec, tube voltage120kV, current200mA,0.625mm reconstructed section thickness for angiography post-procession. Intravenous contrast was administered to each patient with signed consents. Nonionic, low-osmolar contrast mediums (Iohexol or Omnipaque) were used. The protocols of contrast administration were routine for pelvic CT examination in this institute.80-100ml of contrast material followed by20ml of normal saline at a rate of2-3ml/sec was injected for the CT angiographic acquisition. No pre-contrast scans were required. The post-contrast scans were obtained after a delay of70-80s from the start of contrast material injection.In part2, two group of image was acquired, one is cranial group the other is facial group. Each group contains10patients. All patients were scanned on one of the two multidetector-row CT scanners in one institute, scanner A (Discover CT750HD, GE Healthcare) and scanner B (LightSpeed VCT, GE Healthcare). The scanning protocols were almost the same for both scanners. Scanning range was from12～15cm above the level of external auditory to5cm below the level of external auditory in cranial group. While in facial group the scanning range was from the supra orbital rim level or above, to10cm below the level of lower margin of mandibular bone.Both in part1and part2, all DICOM format data was then input into Osirix software. Various kinds of three-dimensional reconstruction were made with each DICOM data to observe the anatomical features of the superficial vessels of the groin area. The step-by-step volume rendering and multiple planar rending techniques were established for both the superficial groin vessels and superficial facial vessels. Measurements were done in both the sliced images and three-dimensional images.In part3,6patients were included from March to August in2012in plastic surgery department of Peking Union Medical College Hospital. All received superficial circumflex iliac artery perforator flap transfer for facial soft tissue reconstruction. All the flaps were done in the similar way.The results are as following:1. The course of superficial circumflex iliac vein is different than that of the superficial circumflex iliac artery. These two vessels are in close relation near the femoral triangular area, but they keep away with each other in the distal area.2. Numerous branches originate from the superficial circumflex iliac artery, these including:the descending branch; the superficial branch; the lymph node branch; the muscular branch; the perforator branch; and the extension of the main trunk of this vessel.3. Perforator vessels can be observed in each groin area. At least two perforator vessels can be found when the superficial circumflex iliac artery travels through (or on the surface of) Sartorius muscle. The perforator can arise from the father vessel on various locations:at the medial side of the Sartorius m., in the middle portion of the same muscle, at the lateral side of the muscle. The perforator will always travel in the lateral-inferior direction, which constitutes an "F" figure along with the father vessels.4. Based on the branch pattern of the superficial circumflex iliac artery, various kinds of flap can be designed based on the same artery. The superficial circumflex iliac artery based flap will be versatile in reconstructive surgery with so many variations.5. Facial superficial vessels mainly include two sets of vessels:the facial artery and vein, the superficial temporal artery and vein. In this research, the middle temporal vein is found to be readily observed along with aforementioned vessels. So this vessel should be included as an option of superficial facial recipient vessels.6. The facial artery and vein keep a close relationship at the submandibular area, and keep away from each other in the midface area. In the inferior medial area of the orbital, an intercrossing phenomenon of these two vessels can be observed.7. In preauricular area, the middle temporal vein is an alternative option for superficial temporal vein. For the former always present with large caliber while the latter is smaller than the former.8. The middle temporal vein travels medially and branch off ascending and descending tributary to drain the superficial temporal area.9. An intercrossing phenomenon of the forehead branch of the superficial artery and ascending branch of the middle temporal vein can be observed in the lateral superior area of the orbital.10. There are four potential recipient vessels exposure area in the face:the submandibular area (zone A), the pretarsal area (zone B), the inferior medial area of orbital (zone C) and the lateral superior area of the orbital (zone D). 11. In clinical observation, the perforator pattern is the same as concluded in part1. The superficial circumflex iliac artery perforator flap can be raised in six patients.12. With appropriate microdissection technique, the superficial circumflex iliac artery perforator flap can be thinned with a thickness of3mm.13. The recipient vessel zone theory been used in six patients. One zone C and one zone D was used and without any accident.14. All microdissected superficial circumflex iliac artery perforator flap survival completely.Conclusions:1. The superficial circumflex iliac artery perforator has its own anatomic distribution features and course patterns. This knowledge will help plastic surgeon to reliably and efficiently design this new kind of flap.2. There are four potential recipient vessel exposure area for facial microsurgical reconstruction. The zone C and zone D is the first time being introduced.3. The superficial circumflex iliac artery perforator flap can be easily raised and safely thinned and securely anastomosis with the four recipient facial exposure zones.4. The feasibility of superficial facial reconstruction with superficial circumflex iliac artery perforator flap has been proved in this research. We believe that this new kind of flap will become one of the most versatile options for covering soft tissue defects in head and neck reconstruction. |
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