Toshiharu Minabe

Accompanying arteries of the lesser saphenous vein and sural nerve: anatomic study and its clinical applications.

The arteries adjacent to the lesser saphenous vein and sural nerve were investigated in 10 fresh cadavers that had been systemically injected with a lead oxide-gelatin mixture. The accompanying arteries were found to lie along the lesser saphenous vein and sural nerve and to nourish the skin through venocutaneous and neurocutaneous perforators. On the basis of the anatomy of these accompanying arteries, the lesser saphenous venoadipofascial (VAF) pedicled fasciocutaneous flap and the lesser saphenous-sural veno-neuro adipofascial (V-NAF) pedicled fasciocutaneous flap have been developed and applied to 23 cases of various reconstructions of the lower extremity with proximal and distal bases. Survival of the flaps has been extremely good, and the flaps have been clinically useful.

Accompanying arteries of the cutaneous veins and cutaneous nerves in the extremities: anatomical study and a concept of the venoadipofascial and/or neuroadipofascial pedicled fasciocutaneous flap.

&NA; The arterial anatomy of the accompanying arteries of the cutaneous veins and cutaneous nerves in the extremities was investigated in 10 fresh cadavers that had been injected with a lead oxide‐gelatin mixture throughout the entire body. It is well known that cutaneous nerves have neurocutaneous perforators, but it was found that cutaneous veins also have their own accompanying arteries as well. The accompanying arteries of the cutaneous veins had branches not only to the vein wall, but also to the skin, i.e., venocutaneous perforators. Based on these findings, the concept of the adipofascial pedicled fasciocutaneous flap using the accompanying arteries of the cutaneous veins, cutaneous nerves, or both was proposed. (Plast. Reconstr. Surg. 102: 779, 1998.)

The arterial anatomy of the temporal region and the vascular basis of various temporal flaps

The arterial anatomy of the temporal region was examined macroscopically and radiographically in 10 fresh cadavers which had been injected with lead oxide. The blood supply of the temporal region is derived from the superficial temporal, middle temporal, deep temporal, posterior auricular, transverse facial, zygomatico-orbital, zygomaticotemporal, zygomaticofacial, and middle meningeal arteries. The vascular network formed by these arteries can be divided into four arterial networks corresponding to the different layers of the temporal region. With a new understanding of the arterial networks and their anastomoses, the techniques for elevating various flaps in the temporal region are discussed.

Three-dimensional analysis and classification of arteries in the skin and subcutaneous adipofascial tissue by computer graphics imaging

&NA; To develop new types of surgical flaps that utilize portions of the skin and subcutaneous tissue (e.g., a thin flap or an adipofascial flap), three‐dimensional investigation of the vasculature in the skin and subcutaneous tissue has been anticipated. In the present study, total‐body arterial injection and three‐dimensional imaging of the arteries by computer graphics were performed. The full‐thickness skin and subcutaneous adipofascial tissue samples, which were obtained from fresh human cadavers injected with radioopaque medium, were divided into three distinct layers. Angiograms of each layer were introduced into a personal computer to construct three‐dimensional images. On a computer monitor, each artery was shown color‐coded according to the three portions: the deep adipofascial layer, superficial adipofascial layer, and dermis. Three‐dimensional computerized images of each artery in the skin and subcutaneous tissue revealed the components of each vascular plexus and permitted their classification into six types. The distribution of types in the body correlated with the tissue mobility of each area. Clinically, appreciation of the three‐dimensional structure of the arteries allowed the development of several new kinds of flaps. (Plast. Reconstr. Surg. 102: 748, 1998.)

Dorsal intercostal artery perforator flap : Anatomical study and clinical applications

Background: The posterior intercostal arteries form the largest angiosome in the torso by means of their many perforators to the skin, the arteries of which are proposed to be the vascular pedicle of an island flap. Using these perforators, the authors developed a new flap, the dorsal intercostal artery perforator flap, harvested in the back. Methods: An anatomical study was conducted on five fresh human cadavers injected with a lead oxide–gelatin mixture as a radiopaque agent. The study consisted of the cadaver dissection and the angiographic studies to map the dorsal intercostal artery perforators in detail. Results: Each of the fourth to twelfth posterior intercostal arteries consistently supplied the dorsal perforators. Those derived from the fourth, fifth, sixth, tenth, and eleventh posterior intercostal arteries were the dominant direct cutaneous perforators. They were located within 5 cm of the spinous processes of the vertebrae and were clinically detectable by Doppler probe preoperatively. Eleven dorsal intercostal artery perforator flaps were applied in 10 cases. In nine cases, the muscles of the latissimus dorsi, the trapezius, or the scapular circumflex artery had been sacrificed in previous operations. The maximum flap dimension was 31 × 13 cm. All flaps showed stable postoperative blood circulation and survived completely, except for marginal necrosis in the largest flap. No functional loss attributable to flap harvest was recognized. Conclusion: Flap extendibility and less invasiveness without sacrifice of the underlying muscles have proved that the dorsal intercostal artery perforator flap is a new reconstructive option in the back, where suitable flaps are often proposed.

Venous drainage architecture of the temporal and parietal regions: Anatomy of the superficial temporal artery and vein

&NA; Anatomy of the superficial temporal artery and vein was analyzed with arteriograms, venograms, and arteriovenograms of fresh cadavers that had been injected with contrast medium. The superficial temporal artery always divided into two major branches: the frontal and parietal branches. However, the superficial temporal vein divided into one, two, or three major branches. The distribution area of the major branches of the superficial temporal vein was larger than that of major branches of the superficial temporal artery, and arteriovenograms clearly demonstrated that, except for its proximal portion, the superficial temporal vein was independent of the superficial temporal artery. The frontal and parietal branches of the superficial temporal artery had thin venae comitantes that originated from the proximal portion of the superficial temporal vein, and the venae comitantes gave off branches toward the skin and the underlying soft tissue. Branches to the skin anastomosed with a superficial venous network in the skin layer, which was formed by ramifications of the superficial temporal vein. The venous architecture of the temporal and parietal regions consisted of cutaneous veins and venae comitantes and was basically similar to that of the forearm and scapular region. (Plast. Reconstr. Surg. 109: 2197, 2002.)

Comparison of three different supercharging procedures in a rat skin flap model

A significant clinical problem in reconstructive surgery is partial loss of a pedicled flap. To resolve this problem, various methods of vascular augmentation have been developed; “supercharging” is one of those techniques. A new rat flap model was developed for investigation of the supercharging procedure, and the efficacy of the arterial supercharging method was examined. The purpose of this study was to investigate how an arterial supercharging procedure could generate large flap survival areas with different supercharging positions in rats. On the basis of the vascular anatomical features of rats, a circumferential skin flap from the lower abdomen to the back, measuring 4 × 12 cm, was marked. The flap was divided along the dorsal midline. Forty rats were divided into four experimental groups, as follows: group 1 (control), flaps based only on the deep circumflex iliac artery and vein; group 2, flaps supercharged with the ipsilateral superficial inferior epigastric artery; group 3, flaps supercharged with the contralateral superficial inferior epigastric artery; group 4, flaps supercharged with the contralateral deep circumflex iliac artery. On the fourth postoperative day, the flaps were evaluated with measurements of necrosis and survival areas. Microfil (Flow Tech, Inc., Carver, Mass.) was then injected manually throughout the body, and the vascular changes produced by supercharging were angiographically evaluated. Compared with group 1 (control), the flap survival areas were significantly greater in distally supercharged flaps in groups 3 and 4 (mean flap survival, 91.2 ± 5.2 percent and 90.5 ± 10.6 percent, respectively; p < 0.001) and in proximally supercharged flaps in group 2 (45.9 ± 4.1 percent, p < 0.05). Angiographic assessment of the flaps that survived completely revealed marked dilation of the choke veins among the territories and reorientation of dilated veins along the axes of the flaps. This study suggests that distal arterial supercharging (contralateral superficial inferior epigastric artery or contralateral deep circumflex iliac artery) is more effective than proximal arterial supercharging (ipsilateral superficial inferior epigastric artery) in increasing flap survival. Although the rat skin flap may not be analogous to human flaps, distal arterial supercharging might have useful therapeutic potential in increasing flap survival in clinical practice.

Effect of venous superdrainage on a four-territory skin flap survival in rats.

Background: In a previous report, the authors demonstrated that distal arterial supercharging is more effective at increasing flap survival. There is no doubt of the benefit of arterial augmentation in flap surgery, but the effect of venous superdrainage is still controversial. The purpose of this study was to investigate how venous augmentation could generate larger flap survival areas with different superdrainage positions in rats. Methods: A four-territory skin flap, developed by the authors, was used. Forty rats were divided into four groups, as follows: group 1, flaps based only on the deep circumflex iliac artery and vein; group 2, flaps superdrained with the ipsilateral superficial inferior epigastric vein; group 3, flaps superdrained with the contralateral superficial inferior epigastric vein; and group 4, flaps superdrained with the contralateral deep circumflex iliac vein. On the fourth postoperative day, the flaps were assessed by measurements of necrosis and survival areas. Vascular changes produced by venous augmentation were evaluated angiographically. Results: Compared with group 1 (mean flap survival, 37.8 ± 5.0 percent), the flap survival areas were significantly greater in the superdrainage flap groups (group 2, 57.4 ± 6.5 percent, p < 0.001; group 3, 72.4 ± 21.3 percent, p < 0.001, and group 4, 89.2 ± 18.8 percent; p < 0.001). Angiographic assessment of the flaps revealed dilatation of the choke vein between the territories and reorientation of dilated veins along the long axes of the flaps. Conclusions: This study demonstrates that venous augmentation is also effective for increasing flap survival, and the distal procedure is more effective than the proximal procedure in arterial supercharging.

Free Pectoral Skin Flap in the Rat Based on the Long Thoracic Vessels : A New Flap Model for Experimental Study and Microsurgical Training

The purpose of this study was to investigate the vascular anatomy of the pectoral region of the rat to develop a free pectoral skin flap model. In Experiment 1 (n = 6), we performed anatomic dissection and angiographic study of the pectoral region. In Experiment 2 (n = 20), we performed microsurgical free transfer of a pectoral skin flap to the cervical or groin region. Half of the flaps were transferred with flow-though arterial anastomoses. All flaps survived except for 2 cases of autocannibalization. We conclude that the free pectoral skin flap model in the rat is simple and reliable, and can be used as an alternative experimental and training model to the superficial epigastric flap.

Three-dimensional reconstruction of cutaneous arteries of the back by computer graphic imaging.

&NA; Computer graphics using a personal computer were introduced to demonstrate the three‐dimensional architecture of cutaneous arteries of the back in humans: the direct cutaneous artery of the circumflex scapular artery and the perforating cutaneous branches and musculocutaneous perforators of the superficial cervical, posterior intercostal, and thoracodorsal arteries. The entire thickness of the skin and underlying subcutaneous tissue over the deep fascia was obtained from five fresh cadavers injected systemically with lead oxide‐gelatin mixture, and the integument was divided into the three layers: the skin, superficial adipofascial layer with the superficial fascia, and the deep adipofascial layer. Computer graphic reconstruction of the cutaneous arteries was performed using data based on angiograms of the three layers. The computer graphic depictions demonstrated in which layer cutaneous arteries branched and how the vessels were running in each layer by displaying each layer in different colors: red, yellow, and blue. Knowledge of the threedimensional structure and architecture of the cutaneous arteries will aid in the development of flaps that use a portion of the skin and subcutaneous adipofascial tissue. (Plast. Reconstr. Surg. 100: 381, 1997.)