Staged transfer of a free microvascular latissimus dorsi myocutaneous flap using saphenous vein grafts

The use of long vein grafts in the axilla adds a new dimension to the versatility of the latissimus dorsi myocutaneous flap. When suitable recipient vessels are not available for a microvascular anastomosis, long vein grafts can be used in the axilla to double the arc of rotation of the flap, allowing it to cover the buttocks, lower torso, and scalp (Fig. 8). A case is presented in which the latissimus dorsi myocutaneous flap was transferred in stages to cover a large radiation ulcer of the right buttock.     

The safety of microvascular free tissue transfer in the elderly population

The objective of this study was to evaluate the safety and thus the efficacy of microvascular free tissue transfer in the elderly patient population. Free flaps for different types of reconstructions were analyzed to verify whether free tissue transfer is feasible in the elderly. Between 1993 and 2003, 102 free flaps were performed in 94 patients who were aged 70 years or older. There were 75 male and 19 female patients, with a mean age of 73.8 years (range, 70 to 87 years). Different types of free flaps were performed for head and neck (n = 78), lower extremity (n = 12), and trunk and upper extremity (n = 4) reconstruction. Nine flaps underwent reexploration and four of them were lost, for an overall success rate of 96 percent. Medical complications in the postoperative period were further evaluated. A total of 32 medical complications were seen in 29 patients. Only one patient died because of postoperative complications. The frequency of medical complications was further analyzed in detail. Effects of American Society of Anesthesiologists status, operation time, and age on complication rate were evaluated statistically. Only American Society of Anesthesiologists status was statistically significant for the occurrence of postoperative medical complications; class III and IV patients were at higher risk than class I and II. Neither operation time nor age was predictive of postoperative complications. Microvascular free tissue transfer is a safe and reliable option in the elderly population. The success rate of free flaps is not different from that for other age groups. The rate of postoperative medical complications was 31 percent (29 of 94 patients); most complications were in American Society of Anesthesiologists class III and IV patients.     

Thumb reconstruction by free microvascular transfer of an injured index finger

Thumb reconstruction for amputation at the metacarpal phalangeal level was accomplished by microneurovascular transfer of the contralateral damaged index finger ray, including metacarpal phalangeal joint. This transfer accomplished a successful thumb restoration and removed a cumbersome index finger amputation stump, improving function in both hands. This case emphasizes the merits of spare part transfer in hand reconstructive surgery made possible by microneurovascular techniques.     

One-stage microvascular transfer of a latissimus flap to the sacrum using vein grafts

A large irradiated wound of the lumbosacral area is covered in one stage with a latissimus dorsi musculocutaneous flap by "extending" the vascular pedicle with 25-cm interpositional vein grafts.     

The preexpanded radial free flap

The experimental basis for free-flap preexpansion is briefly discussed. Two cases are reported in which the ankle/heel area was resurfaced and reinnervated with a preexpanded radial flap. The size of the first flap was half the surface area of the entire forearm. Direct closure of the secondary defect was possible with a single scar and without functional deficit in both cases. The flaps were well-vascularized and consisted of the sensory distribution of one peripheral nerve division, which was anastomosed in the recipient site. This preparation proved to be finer and to have better contouring capacity and skin quality than existing alternatives. It is clear that hydraulic tissue expansion facilitates great additional use of the radial flap as well as a range of other modified free flaps when there is time available for the flap to be developed prior to transfer.     

Delayed neovascularization in free skin flap transfer to irradiated beds in rats

A model for the study of neovascularization with a normal epigastric free flap set into an irradiated defect in the Fischer F344 rat is presented. In this model, both the administration of radiation and the flap transfer mimic the clinical situation. Significantly less tissue survives loss of the complete vascular pedicle at the second to fourth days following flap creation in rats with an irradiated bed. Later survival is not different from controls. Delayed neovascularization is proposed as the mechanism responsible for this effect during the period corresponding to the onset of the late phase of the response to skin radiation in rats. That neovascularization does occur, although delayed, suggests that the induced endarteritis may not be as important as previously suggested.     

The chondrocutaneous postauricular free flap

Use of the auriculomastoid region as a donor-site for a microvascular free flap is still not the general consensus. This report presents three patients with composite tissue defects of the face aesthetically reconstructed with a chondrocutaneous postauricular free flap. For its safe surgical application, additional anatomic knowledge was refined with cadaver study. Use of the chondrocutaneous postauricular free flap has some merits. Its dissection is straightforward and safer than when only the cutaneous unit is used. It also offers a more dependable vascularized composite tissue as a one-stage operation. With freedom of design, a variable combined facial defect can be delicately reconstructed. The final aesthetic results obtained were gratifying, and the donor-site deformity was minimal.     

The free iliac flap: a lateral modification of the free groin flap.

A lateral modification of the free groin flap, called the free iliac flap, is presented. By moving the outline of the free groin flap laterally, so that the medial margin lies lateral to the underlying femoral triangle, a flap is obtained which is uniformly slender and which has a long vascular pedicle. The anatomical findings, a method for safe dissection of the superficial circumflex iliac vessels, and the results of 18 clinical cases are presented.     

The cost of departure from optimal radii in microvascular networks

In the Murray optimality model of branching vasculatures, the radii of vessels are related to blood viscosity, vascular metabolic rate, and blood flow rate, in such a way as to minimize the total work (hydraulic and metabolic) of the system. The model predicts that flow is proportional to the cube of a vessel radius, and that at junctions the cube of the radius of the parent vessel equals the sum of the cubes of the daughter radii. In comparing real vasculatures to the Murray model, we have previously had no expressions for evaluating the apparent energy cost for departures from the optimal junction exponent of 3. Such expressions are derived here. They show that junction exponents, from about 1.5 to large positive values, are within 5% of the energy minimum. With the new equations, observed individual junctions or entire vascular trees can be compared, energy-wise, with the Murray optimum. Junctions in the transverse arteriolar trees of cat sartorius muscle were compared to the Murray optimality model, using these new expressions. The junction exponents for these small pre-capillary vessels had a broad range, with a median value greater than the Murray optimum of 3. The exponents were restricted, however, to values requiring, at individual junctions, little increase in energy. The majority of junctions had energy costs less than 1% above the Murray minimum. For entire trees involving many junctions the departures from optimality averaged less than 10%. Thus, while the branching geometry for these microvascular trees deviates significantly from the Murray optimum in the direction of larger daughter to parent ratios, the departures are small in energy terms.