B.McC. O'Brien

Prefabrication of thin transferable axial-pattern skin flaps: an experimental study in rabbits

The arteriovenous pedicle of all known axial-pattern skin flaps enters from the deep aspect and consequently the flap must contain fat and/or muscle and be of considerable thickness. In an attempt to fabricate a thinner axial-pattern flap the femoral artery and vein of rabbits were implanted, in various vascular configurations, directly into the subdermal layer of the skin. Implantation was found to provoke an extensive outgrowth of new vessels from the implanted artery and vein, and the progress and pattern of this neovascularisation was studied by carbon gelatine perfusion and histology. Neovascularisation begins within a few days of implantation and progresses rapidly. By 8 to 12 weeks it is possible to elevate regularly a viable, large skin flap based on the implanted pedicle.

How soon may the axial vessels of a surviving free flap be safely ligated: A study in pigs

The supplying vessels of microvascular free flaps in pigs were ligated at various intervals after transfer in order to study the revascularisation from the recipient bed. At 8 days of later survival occurred. Earlier, although necrosis was not inevitable, the results were unpredictable.

Lymph node transfer for the treatment of obstructive lymphoedema in the canine model

The efficacy of transferring vascularised lymph nodes into lymphoedematous limbs was investigated. Stable below-knee lymphoedema was established in one hind limb of 10 dogs. The superficial inguinal lymph node and perinodal tissue from the normal hind limb was moved to the popliteal region of the lymphoedematous leg as a free vascularised transfer. In five dogs lymphaticolymphatic anastomoses between lymphatics of the node and proximal recipient site lymphatics were also performed. Circumferential measurements of the foot, ankle and midleg were obtained preoperatively and postoperatively at 3 and 6 months. These measurements showed postoperative reduction of the lymphoedematous legs compared to controls, with no added benefit from lymphaticolymphatic anastomoses. Technetium 99 scans and lymphangiography demonstrated re-establishment of lymphatic continuity in all recipient legs at 3 and 6 months post-transfer. Histological examination at 3 and 6 months revealed normal architecture in 9 of 10 nodes, although areas of lymphocyte depletion were common. Vascularised lymph node transfer to a lymphoedematous leg re-established lymphatic continuity and resulted in partial reduction of limb size. The addition of lymphaticolymphatic anastomosis to vascularized node transfer is neither necessary nor beneficial.

Liposuction in the treatment of lymphoedema; a preliminary report

Liposuction was used in the treatment of primary and secondary lymphoedema in 19 patients. Seven patients had no previous surgical treatment and 12 had previously been treated with microlymphaticovenous anastomoses and/or surgical reduction. There was subjective improvement in 11 of the 13 patients available for follow-up. There was objective improvement in 10 of the 11 patients with unilateral lymphoedema, with an average reduction of 23% of the excess volume. Seven of the 13 patients were on conservative treatment prior to liposuction. The average reduction in this group was 20.5%. The average follow-up time was 9.5 months. From this preliminary report it can be concluded that liposuction, either as a primary procedure or as an adjunct, can be a useful procedure in the treatment of both primary and secondary lymphoedema.

An experimental evaluation of microvenous grafts.

Vein grafts into I mm vessels were performed with a high success rate, using autografts in rabbits. Failure in most instances was thought to be due to technical errors at operation. The length of the grafts did not alter the patency rate.

Microvascular osteocutaneous transfer using the groin flap and iliac crest and the dorsalis pedis flap and second metatarsal

Abstract It can be concluded that 1-stage free flap bone graft procedures enhance the armamentarium of the reconstructive surgeon. In the 7 cases presented, 5 were completely successful and 2 failed. These latter 2 cases reflect the hard core of unpredictability in the occasional microvascular case. But this should not deter reconstructive surgeons from proceeding. In our experience 80 per cent or more of microvascular reconstructive procedures achieve their aim.

A study of the extent and pathology of experimental avulsion injury in rabbit arteries and veins

A comparison was made between operating microscope observations and histopathological examination of the ruptured ends of experimentally avulsed rabbit femoral arteries and veins. Under the operating microscope no damage was evident in arteries or veins more than 0.8 cm (on average) from the rupture site, the common lesions being tears, holes, bruising, sleeving and dilatations. In light microscope and electron microscope studies arterial and venous lesions were often noted up to 4 cm from the rupture site both proximally and distally. Severe circumferential skip lesions involving the tunica intima and media in the arteries were noted, and commonly deep clefts also extended through all three tunicae at arterial bifurcations. In avulsed veins complete tears through all tunicae or partial loss of intima and media were observed. The extensive nature of these lesions is the most likely reason for the lower success rate of avulsed digits in replantation surgery.

Free flap transfers with microvascular anastomoses

Abstract A series of 9 cases of free flap transfer with microvascular anastomoses in both elective and emergency situations in the limbs, and head and neck is presented. Seven free groin flaps were utilised and 2 lateral forehead flaps for nasal reconstruction following cancer surgery. One flap loss occurred and arterial thromboses in 2 other cases were overcome using vein grafts. Free flap transfer has advantages over tube pedicles and many direct flaps, and broadens the scope of reconstructive surgery.

Free flap transfer in rabbits using irradiated recipient vessels.

In rabbits free flaps anastomsed to irradiated vessels have about a 50:50 chance of survival.

Hallux-to-hand transfer.

Abstract A hallux-to-hand microvascular transplantation for thumb reconstruction is presented and variations in the technique discussed.