Superior gluteal artery perforator free flap for breast reconstruction

The purpose of this paper is to present a new method of breast reconstruction utilizing skin and fat from the buttock without muscle sacrifice. Cadaver dissections were done to study the musculocutaneous perforators of the superior gluteal artery and vein. Eleven breasts were reconstructed successfully with skin/fat flaps based on the superior gluteal artery with its proximal perforators. Long flap vascular pedicles allow the internal mammary or thoracodorsal vessels to be used as recipient vessels. This new technique has several advantages over the previously described gluteus maximus myocutaneous flaps, including long vascular pedicle and no muscle sacrifice.     

Cell cultures and nephrolithiasis

Large bone flaps for free transfer can be successfully and safely harvested based on the deep branch of the superior gluteal artery. The anatomy is consistent, the vessels are large, and the complications of this technique are minimal.     

Which vessel is more important in the supercharged flap--artery, vein, or both? An experimental study

The supercharged flap is one which is expected to attain better survival, by anastomosing the distal vessels of the flap to the recipient vessels. An experimental study is reported to determine whether the vessel to be anastomosed should be an artery, a vein, or both. The authors advise anastomosing an artery and a vein, but they believe that arterial inflow is more important than venous drainage.     

Posterior interosseous free flap: various types

The posterior interosseous artery is located in the intermuscular septum between the extensor carpi ulnaris and extensor digiti minimi muscles. The posterior interosseous artery is anatomically united through two main anastomoses: one proximal (at the level of the distal border of the supinator muscle) and one distal (at the most distal part of the interosseous space). In the distal part, the posterior interosseous artery joins the anterior interosseous artery to form the distal anastomosis between them. The posterior interosseous flap can be widely used as a reverse flow island flap because it is perfused by anastomoses between the anterior and the posterior interosseous arteries at the level of the wrist. The flap is not reliable whenever there is injury to the distal forearm or the wrist. To circumvent this limitation and to increase the versatility of this flap, we have refined its use as a direct flow free flap. The three types of free flaps used were (1) fasciocutaneous, (2) fasciocutaneous-fascia, and (3) fascia only. Described are 23 posterior interosseous free flaps: 13 fasciocutaneous flaps, 6 fasciocutaneous-fascial flaps, and 4 fascial flaps. There were 13 sensory flaps using the posterior antebrachial cutaneous nerve. The length and external diameter of the pedicle were measured in 35 cases. The length of the pedicle was on average 3.5 cm (range, 3.0 to 4.0 cm) and the external diameter of the artery averaged 2.2 mm (range, 2.0 to 2.5 mm). The hand was the recipient in 21 patients, and the foot in 2. All 23 flaps covered the defect successfully.     

Blood flow in free muscle flaps measured by color Doppler ultrasonography

Color Doppler ultrasonography, a noninvasive method for studying changes in blood flow, has been used to monitor 18 patients with free microvascular lower limb muscle flaps. The peak, mean, and minimum velocities, resistance indices, and diameters of the flap pedicle arteries and also of the limb recipient arteries proximal to the microvascular anastomoses were measured at 2 and 6 weeks and 3, 6, and 9 months after surgery. The peak velocities did not significantly differ from each other, but the mean velocity in the flap pedicle arteries was 12.5% higher than that in the recipient arteries throughout the study period. End diastolic velocity in the pedicle was positive (toward the ultrasound probe) at 2 weeks (mean, 2 cm/sec, SD 10), 6 weeks (mean, 5 cm/sec, SD 16), and 3 months (mean, 3 cm/sec, SD 13) after surgery and significantly higher (P < 0.05) than at 6 months (mean, 7 cm/sec, SD 11), when the pattern of blood flow was normal forward/backward flow during systole/diastole. The resistance indices of the pedicle at 2 weeks (Ri = 0.978), 6 weeks (Ri = 0.936), and 3 months (Ri = 1.001) were significantly lower (P < 0.05) than at 6 months (Ri = 1.108), when the pedicle and recipient artery indices were the same. The diameter of the pedicle arteries was 14% smaller than those of the recipient arteries, but did not change during follow-up. This prospective clinical study shows that blood flow in the pedicle of a free microvascular muscle flap is increased until 6 months after surgery, mainly due to the increased minimum velocity of the pedicle in diastole and decreased resistance index. These findings can be attributed to the loss of vessel tone after denervation and are in accordance with earlier studies showing that denervated muscles lose their autoregulation and that blood flow increases, but that these phenomena subside with time. Increased blood flow in free muscle flaps can explain the high success rate of microanastomoses and positive effect on wound healing.     

Internal mammary artery and vein supercharge in TRAM flap breast reconstruction

To improve the blood supply of the pedicled flap we have performed an additional microvascular augmentation to this type of breast reconstruction procedure since 1991. The ipsilateral deep inferior epigastric pedicle is anastomosed to the internal mammary artery and vein (IMAV supercharge). In 19 of 20 patients this technique proved to be feasible. For the venous anastomoses the 3M microvascular anastomosis system facilitated the procedure. In one patient the venous anastomosis failed due to the small calibre of two internal mammary veins. In a majority of the cases rapid improvement of flap perfusion could be observed as the direct result of the supercharging. The IMAV supercharged flap is quite comparable with the free flap as regards to the operative procedure. Disadvantages are a slightly more extensive dissection and less freedom in positioning the flap due to the presence of the superior muscular pedicle. The main advantage is that the supercharge procedure minimises the risk of total flap loss. Further technical improvement may be obtained by the use of a contralateral vascular pedicle dissected with muscle-sparing techniques.     

Recipient bed vascularity and the survival of ischaemic flaps

The purpose of this study was to identify the length of the ischaemic period required to induce the 'no-reflow' phenomenon in a rat epigastric flap on an avascular recipient site. The vascularity of the recipient bed may affect flap survival in the early postischaemic stage after flap transfer. Initially, we designed epigastric flaps in 300-350 g Sprague-Dawley rats and separated the rats into four groups of 5 rats each (total 20 rats). In groups 1, 2, 3, the flaps were made ischaemic for 1 hour, 6 hours and 10 hours, respectively, by temporarily clipping the epigastric artery and vein. In group 4, the epigastric artery and vein were divided to create permanent ischaemia. In groups 1, 2 and 3, ischaemia was ended by removing the clips. After the ischaemic flaps were reperfused, their viability was studied by measuring the flap survival rate at postoperative day 7. Flap survival was studied by direct observations, laser Doppler flowmeter measurement of flap blood flow, histopathology, and carbon particle perfusion of the flap vasculature. Ischaemic flaps of groups 1 and 2 recovered almost completely after reperfusion due to the short period of ischaema. In a second series of experiments, in order to evaluate the contribution to flap survival of the recipient vascularised bed, another four groups of epigastric flaps (of 5 animals each, using the same time periods as above) were raised and a piece of Biobrane was interposed between the flap and the recipient bed before the flap wound was closed, to eliminate all nutrient supply from the recipient bed. THe results showed that the combined effect of the reperfused flap vasculature plus the metabolic contribution of the recipient bed significantly (P < 0.01) increased the extent of flap survival of the 6- and 10-hour ischaemic flaps as well as the divided pedicle flaps, which were never reperfused. An absolute 'no-reflow' rat model flap for further flap salvage studies was also developed.     

Muscular urinary sphincter: electrically stimulated myoplasty for functional sphincter reconstruction

PURPOSE: To reconstruct an electrically stimulated muscular urinary sphincter (MUS) using a tailored gracilis muscle free flap with intact nerve. MATERIALS AND METHODS: Unilateral surgically tailored gracilis muscle free flaps were transferred into the pelvis in eight dogs, leaving the obturator nerve intact. The muscle's pedicle vessels were anastomosed to the inferior epigastric artery and vein in the pelvis and the muscle was wrapped around the bladder neck. Electrodes were inserted into the MUS and connected to a programmable pulse generator. After 8 weeks of training the MUS, the pulse generator was programmed to be "on" for 4 hours and "off' for 15 minutes in a continuous cycle. Urodynamic studies were performed periodically, and at the end of the experiment the MUS and proximal urethra were harvested for histology. Three control dogs had sham operations. RESULTS: All MUS's functioned well following the procedure. Histology of the MUS/urethra complex showed no evidence of stricture. Except for one dog, all urethras were easily catheterized. CONCLUSIONS: This electrically stimulated innervated free-flap MUS technique effectively increases bladder outlet resistance without producing urethral obstruction.     

Use of 20 cm or longer interposition vein grafts in free flap reconstruction of the trunk

Between January of 1993 and September of 1995, six microsurgical free tissue transplants were performed using saphenous vein grafts ranging from 20 to 39 cm in length. All six free flaps survived. Two wounds were caused by radiation injury and two by tumor resection. The remaining two free flaps were performed for contour deformity and spinal cord coverage. All of the recipient sites were located on the trunk. In each case, an arteriovenous loop was created before the microvascular anastomosis to the free flap. There was one arterial thrombosis requiring thrombectomy and revision of the anastomosis. Three patients developed minor wound complications that responded to local wound care. Each of the flaps successfully provided wound coverage, and in two cases the flaps tolerated further radiation results. Long interposition vein grafts can be used for difficult microsurgical reconstructive procedures with reliable results when no local recipient vessels are available. Versatility is therefore afforded in placement of the flap and the choice of recipient vessels, making this option a useful one in the treatment of complex wounds of the trunk.     

A locus for autosomal recessive hypodontia with associated dental anomalies maps to chromosome 16q12.1

Lumbosacral defects on 20 patients were covered with a perforator-based flap. Cutaneous perforators derived from the 9th and 10th intercostal arteries, the 4th lumbar artery, and multiple gluteal perforators that penetrate the gluteus maximus muscle were used as vascular pedicles. Minor complications occurred in five cases. Using this method, minimal morbidity of the donor site is expected because the gluteus maximus need not be sacrificed. Accordingly, perforator-based flaps are especially indicated for ambulatory patients, but for paraplegic patients as well. Even in the event of recurrence, another perforator-based or musculocutaneous flap can be elevated from the ipsilateral side because of the presence of multiple perforators in the lumbosacral and gluteal regions.     

One-stage total penile reconstruction with a free sensate osteocutaneous fibula flap

This is the first series of total penile reconstructions with the free sensate osteocutaneous fibula flap. The main advantages of this flap lie in its intrinsic rigidity, its superior donor-site location, and its long vascular pedicle. The fibula flap provides better bone volume than does the radial forearm flap, which commonly results in a floppy phallus in the absence of bone. Penile prostheses in other flaps have enjoyed limited success. Forearm donor-site complications can be avoided. The donor site in the lower extremity can be readily covered with a sock. The vascular pedicle of the fibula flap is of sufficient length to allow end-to-side anastomosis of the flap to the femoral artery. Interpositional vein grafts are unnecessary, and dissection of the inferior epigastric artery system to serve as a donor artery may be avoided. The appearance of the neophallus is excellent. We present only the first four continuous cases of the six we have performed because sufficient follow-up data are available only for these four. The advantages and disadvantages of fibula and forearm donor sites, the long-term fate of the bony component, the importance of sensation, and the vascularized urethral reconstruction are discussed. High patient satisfaction and the advantages of the technique convince us that the fibula osteocutaneous flap is superior for total penile reconstruction.     

Surgical cover of dorsolumbar radionecrosis. Apropos of 6 cases

Thoracolumbar radionecrosis may be difficult to cover. We often use muscular or myocutaneus flaps available in this location, mainly the latissimus dorsi flap. It can be used as a pedicle, free, or especially a "reversed" flap with lumbar pedicles. However in our experience and in the literature this reversed flap is difficult to use because of the morbidity of the flap, transposed without its main pedicle. The authors consider the current methods of cover by flaps in six cases and in the literature. Surgical possibilities are now more numerous. First, a latissimus dorsi muscular flap autonomized by vascular delay, half-free flap, or a flap with the lengthening of its pedicle is possible. Second, we can also use an intercostal island flap for the back and a gluteal thigh flap in the lumbar region.     

Thrombin induces thrombomodulin mRNA expression via the proteolytically activated thrombin receptor in cultured bovine smooth muscle cells

We propose that a long-term cure for the recalcitrant chronic venous ulcer must involve a dual surgical approach including (1) wide excision of the ulcer and surrounding liposclerotic tissue bed, and (2) replacement by a free flap containing multiple, competent microvenous valves with a normal microcirculation. Advantages of free flaps over skin grafting include improvement of the underlying pathophysiology; increase in blood supply to the area; ability to cover exposed bone, joint, or tendon; and a lower incidence of recurrence. During the past 8 years, 20 consecutive muscle free flaps were performed in 18 patients for 19 recalcitrant venous ulcers (two "sequential" flaps to the ipsilateral leg in 1 patient and a repeat flap after initial failure in 1 patient). Twelve males and 6 females ranged in age from 17 to 76 years (mean, 44 years). Nontraumatic, nonosteomyelitic venous ulcers had been present for an average of 3.5 years (range, 1-10 years) and failed an average of 2.4 skin grafts (range, 0-6 grafts). Defects ranged from 100 to 600 cm2 (mean, 238 cm2). Donor tissues included rectus abdominis (N = 13), latissimus dorsi (N = 5), gracilis (N = 1), and serratus (N = 1) muscles. Recipient vessels included posterior tibial (N = 12), anterior tibial (N = 6), and peroneal (N = 2). In all instances except one, only one vein, usually one of the venae comitantes, was anastomosed in end-to-end fashion. Successful free tissue transfer was accomplished in 18 of 20 flaps (90%). Complications included infection with partial flap and/or skin graft loss (three flaps), and partial skin graft loss (two flaps). There were no recurrences within the flaps; however, breakdown occurred at the junction between the flap and residual adjacent liposclerotic skin in 1 patient. Follow-up average 32.7 months (range, 8-65 months); 3 patients were lost to follow-up. Free muscle transfer can provide a long-term cure for the recalcitrant venous ulcer by replacing the diseased tissue bed with healthy tissue containing multiple, competent microvenous valves and a normal microcirculation. This can be accomplished in one reconstructive procedure with excellent long-term results.     

Comparative pathogenesis of human WA1 and Babesia microti isolates in a Syrian hamster model

The medial thigh flap is a perforator-based flap nourished with septocutaneous or muscle perforators originating from the femoral vessels. To date, 8 patients have been repaired with this flap and extended or connected flaps including this flap: 4 patients with lower leg defects and 4 patients with intraoral and neck defects. The advantages of this flap are (1) several pedicle perforators exist for this flap, which makes possible duplicated vascular anastomoses to establish reliable circulation of the transferred flap; (2) the flap can be extended or connected to other neighboring flaps in the anterior thigh, so that extensively wide defects can be closed in one stage; (3) the great saphenous vein can be simultaneously used as a vein graft or for venous drainage for the flap; (4) the anterior branch of the femoral nerve can be used for sensory potential; and (5) there is minimum morbidity of the donor defect and a large dominant vessel for the leg can be preserved. The suitable indications for this flap are defects after removal of skin cancer in the foot or lower leg and wide defects after resection of head and neck cancer, which can be reconstructed with the flap connected to neighboring skin flaps. The disadvantages of this flap are that it has a small, short vascular pedicle and the bulkiness of the flap's fatty tissue often requires thinning.     

The distally based forearm island flap in hand reconstruction

The distally based forearm island flap is vascularized by the perforators of the distal radial artery. The skin flap is along the axis of the radial artery, and the pivot point of its subcutaneous pedicle is about 2 to 4 cm above the radial styloid process. We have treated 12 patients with 12 flaps for soft-tissue defects of the hand. Of these recipient sites, seven were in dorsal hands, two were in thumbs, two were in forearms, and one was in the palmar area. The donor-tissue variants included eight skin flaps, two adipofascial flaps, and two sensate flaps. The sizes of the flaps ranged from 6 x 4 cm to 14 x 6 cm. The donor site wound could be closed primarily in five patients. Two sensate flaps, innervated by the lateral antebrachial cutaneous nerve, could provide sensation for thumb reconstruction. The advantage of this flap is its constant and reliable blood supply without sacrifice of the main radial artery. The elevation of the flap is simple and rapid. There is the potential that this flap can be used as an innervated flap, and there is no need of microsurgical technique.     

Treatment of complex postoperative lumbosacral wounds in nonparalyzed patients

Postoperative infections after back operations can produce complex wounds with myonecrosis, deep dead space, and exposed orthopedic hardware, bone, and dura. Three ambulatory patients with complex postoperative back wounds that resulted from infections were treated successfully with antibiotics, debridement, irrigation, and closure of deep dead space with a superior gluteal muscle flap. Several surgical maneuvers can be performed to increase the length of the superior gluteal muscle flap. The inferior portion of the gluteus maximus was left intact to preserve gluteus maximus function. All three patients obtained healed wounds. The exposed A.O. plating system was not removed. There has not been any recurrence of infections. The superior gluteal muscle flap is a reasonable flap to fill deep dead space in the low back and has some advantages over free flaps.     

Experimental prevention of free flap thrombosis. I: A model of free flap failure

A model to evaluate the efficacy of therapies aimed at reducing the failure rate of microvascular free flaps was developed in the rat, inspired by earlier work on the rabbit ear by Ozbek et al. (Ann Plast Surg 32:474-477, 1994). It consisted in raising an epigastric groin flap on the femoral pedicle, while cutting the femoral artery, twisting it around the femoral vein, and resuturing it. Immediate patency was always seen, but 19 of 20 such anastomoses presented with thrombosis after 24 hours (15 venous and 4 mixed thromboses). Ten similar anastomoses performed without twisting did not result in thrombosis (P = 0.000000366). This model appears to be adequate for simulating free flap failure.     

MRI of the intracerebral lesions at 0.5 Tesla: comparison of fast spin-echo and conventional spin-echo sequences

The purpose of this study was to identify the angiosome of the medial saphenous artery and vein and to evaluate the use of this cutaneous angiosome as a free skin flap in the dog. In phase 1 of this study, selective angiography of the medial saphenous artery performed in six canine cadavers showed that the skin covering the entire medial femorotibial area, the distal half of the caudal head of the sartorius muscle, and the gracilis muscle were perfused by the medial saphenous artery. In phase 2, a medial saphenous fasciocutaneous island flap was raised and sutured back to the skin edges of the donor wound in three dogs. One hundred percent survival of all of the flaps occurred. In phase 3, a medial saphenous fasciocutaneous microvascular free flap was transferred to a wound that was created over the dorsal metacarpal (n = 3) or metatarsal region (n = 3). The mean length +/- SD of the medial saphenous vascular pedicle was 80 +/- 13 mm (n = 5); the mean diameter +/- SD of the medial saphenous artery was 2.8 +/- 0.2 mm (n = 5) and the mean diameter +/- SD of the medial saphenous vein was 4.2 +/- 0.2 mm (n = 5). One hundred percent of all flaps survived (n = 6). Selective angiography or the distal cranial tibial artery (metatarsal wounds, n = 3) and the median artery (metacarpal wound, n = 3) was performed 3 weeks after surgery. All of the vascular anastomoses were patent and neovascularization of the wound beds was present. This free flap was found to be acceptable for cosmetic reconstruction of wounds located on the distal extremity.     

Sindbis virus infection of neonatal mice results in a severe stress response

A free vascularized rectus abdominis muscle graft with a long motor nerve was used for reconstruction of unilateral established facial paralysis in one stage. Regarding the procedure, the pedicle vessels were anastomosed to the recipient vessels in the ipsilateral face, and the motor nerve of the muscle was sutured to the contralateral facial nerve. The advantages of using the rectus abdominis muscle are as follows: (1) the muscle is very thin, not bulky, (2) the muscle can be split easily to reduce the volume, (3) the intercostal nerve is long enough (more than 20 cm) to reach the contralateral facial nerve for suturing, (4) the pedicle vessels are large and long, (5) it is possible to carry out simultaneous operations with two teams, and (6) the donor-site morbidity is minimal. The disadvantages of this method are that complicated surgical dissection is required to obtain a motor nerve and that a postoperative abdominal hernia may occur.