Bernard McC. O'Brien

The no-reflow phenomenon in experimental free flaps.

The no-reflow phenomenon was studied following reconstitution of blood flow by microvascular anastomosis in an ischemic and denervated free epigastric flap in the rabbit. Microscopic, histological, angiographic, and hematological studies demonstrated the progressive nature of this obstruction to the peripheral blood flow after increasing periods of ischemia. This obstruction reached a point of irreversibility after 12 hours of ischemia, leading to ultimate death of these flaps. These results are consistent with the hypothesis that an ischemia-induced no-reflow phenomenon is caused by cellular swelling, intravascular aggregation, and the leakage of intravascular fluid into the interstitial space. Similarities between these experimental findings and human observations are made. The clinical importance of early diagnosis and treatment of ischemic tissues is emphasized.

Cross-facial nerve grafts and microneurovascular free muscle transfer for long established facial palsy.

Cross-facial nerve grafts followed in 4 to 12 months by microneurovascular free gracilis transplantation can produce adequate reconstruction in the lower two-thirds of a paralysed face. The mixed sensory and motor deep peroneal nerve and the small muscle bulk of the extensor digitorum brevis limit its usefulness in facial palsy. The gracilis has proved to be a much superior muscle. A feasible method for total reamination of unilateral facial palsy is presented.

Long-term results after microlymphaticovenous anastomoses for the treatment of obstructive lymphedema.

Over the last 14 years, 134 patients with obstructive lymphedema have been treated with microlymphaticovenous anastomoses. Ninety patients were available for long-term follow-up study. Of these, 52 patients were treated by microlymphatic surgery only and 38 of them also had segmental or radical reduction surgery, either at the same time or secondarily. Objective assessment was undertaken by volume and circumferential measurements. Initially, lymphangiography was used, but a study demonstrated increased edema immediately following the investigation in one-third of the patients and it was abandoned, both preoperatively and postoperatively. In the microlymphaticovenous anastomoses only group (N = 52), subjective improvement occurred in 38 patients (73 percent). Objectively, volume changes showed a significant improvement in 22 patients (42 percent), with an average reduction of 44 percent of the excess volume. In the microlymphaticovenous anastomoses and reduction surgery, usually segmental, group (N = 38), subjective improvement occurred in 30 patients (78 percent) and objective improvement occurred in 23 patients (60 percent), with an average reduction of 44 percent of the excess volume. Of those followed up, 67 patients (74 percent) have been able to discontinue the use of conservative measures, with an average follow-up of 4.0 years and average reduction in excess volume of 26 percent. There was a 58 percent reduction in the incidence of cellulitis following surgery. In those patients who were improved, drainage resulted in increased softness of the limbs. Edema of the hand diminished considerably in most patients, although this was difficult to measure. These long-term results indicate that microlymphaticovenous anastomoses have a valuable place in the treatment of obstructive lymphedema and should be the treatment of choice in these patients. Reduction surgery can be used as an adjunct in some of these patients, especially in the posteromedial aspect of the upper arm. Liposuction has been used in failed cases or in patients in whom no lymphatics could be found. Improved results can be expected with earlier operations because patients referred earlier usually have less lymphatic disruption.

Free neurovascular flap from the first web of the foot in hand reconstruction

To identify an anatomically reliable and functionally acceptable neurovascular free flap for use in hand reconstruction, 50 fresh cadaver feet were dissected under the operating microscope, with particular attention paid to the anatomy of the first web area. A distal communicating artery was seen in 100% of dissections, allowing either dorsal, or plantar donor artery inflow to nourish the entire flap area. Because of the ease of dissection, the first dorsal metatarsal or dorsalis pedis is suggested as the donor artery, and a dorsal branch of the greater saphenous venous system is suggested as the donor vein. The deep peroneal nerve was seen to consistently innervate the first web and, along with the plantar digital nerves, is suggested as an anatomically identifiable donor nerve. Either part of the foot first web may be used alone or together as a free flap. When indicated further dorsal skin may be incorporated into the web flap to expand its application. Two-point discrimination studies of the lateral plantar surface of the great toe in 50 normal individuals showed an average of 11.2 mm. This was significantly better as a potential donor flap than the medial dorsum of the foot where the average was 32 mm. A single case demonstrating the application of this flap in hand reconstruction is presented.

The instep of the foot as a fasciocutaneous island and as a free flap for heel defects.

The instep flap needs neither muscle nor a transposition base for survival or innervation. It can be transposed as an island fasciocutaneous flap either on the medial or lateral plantar neurovascular bundles or both, and it can be transferred also as a free flap from the opposite foot. Four cases demonstrating the use of the flap as an island and free flap are presented with follow-up ranging from 1 to 2 years. The absence of muscle in the flap provides greater stability of the heel reconstruction and results in a lesser secondary defect. Sensation in the flaps is diminished but adequate for long-term function, but hyperkeratotic reaction remains an unpredictable problem. The ability to transfer the flap as a free transfer widens the scope of the flap to reconstruct both heel and forefoot defects where local instep tissue or vascularity are inadequate for local reconstruction. The secondary defect, particularly when no muscle is included in the flap, has been minimal.

The effect of epidermal growth factor on wound healing in mice

Abstract The data presented in this paper focus attention on the possible evolutionary advantages of communal licking, based upon the delivery of wound healing factors in the saliva to an immediate local injury. It is suggested that epidermal growth factor (EGF) is one of these factors, as topical application of EGF to a standardized back wound in mice caged separately enhanced wound closure in both control and sialectomized animals. A sex difference in the wound closing response was evident from these studies. The testosterone dependence of EGF synthesis and its action on wound closure as well as its release upon α-adrenergic stimulation, make teleological sense, in a context of an acute response to injury caused by fighting. It is also suggested that prostaglandins released in injured tissue may modulate these acute effects of EGF, as prostaglandin inhibitors prevented EGF-induced closure. Since EGF is known to be a potent mitogen for murine fibroblast and epithelial cell lines, it may also participate in longer term effects integral to wound healing.

Results of management of facial palsy with microvascular free-muscle transfer.

This paper reports our experience in facial reanimation using free innervated muscle transfer in 69 patients with long-term facial palsy. The majority of patients were treated in two stages with cross-facial nerve graft as the first stage and microvascular muscle transfer at the second stage. The gracilis muscle was used in 62 patients. A system of grading results has been utilized in the long-term evaluation. The overall final result was excellent or good in 51 percent of 47 patients who were available for follow-up. Although the results are not completely satisfactory, they justify the use of this approach to a difficult clinical problem. The results are improving as technical modifications to the procedure have evolved. The gracilis muscle is a reliable free transfer with internal anatomy conducive to use for reanimation of the paralyzed face. This type of transfer, in our experience, has proved superior to nonmicrosurgical methods for treatment of complete and severe incomplete facial palsy. The seventh cranial nerve is used in the innervation of the transferred muscle, the ipsilateral being preferable if available. The authors believe that use of the same cranial nerve is superior to methods that involve other cranial nerves, where spontaneity is often not achieved.

The late functional results of upper limb revascularization and replantation

The functional results in 25 of 30 patients after successful upper limb revascularization or replantation were evaluated by subjective-patient surveying and objective measurements. Young patients with complete, sharply amputated extremities at the wrist level or those with incomplete injuries and uninjured peripheral nerves had the best functional results. Multiple-level, diffuse crush, or avulsion injuries, even if the injuries were incomplete, and patients with high-level nerve injury had less return of function.

Microlymphaticovenous anastomoses for obstructive lymphedema.

Microlymphatic surgery appears to have a worthwhile clinical application in the treatment of secondary obstructive lymphedema. We prefer 3 or more lymphaticovenous anastomoses at, or above, the elbow; otherwise ablative procedures are recommended. In the selected cases there are some advantages of anastomoses over surgical reduction procedures: (1) the incidence of postoperative cellulitis is significantly less; (2) the microlymphatic techniques are applicable to both upper and lower limbs and perhaps could be extended to localized cases of obstructive lymphedema following trauma and congenital constriction bands. Considerable experience in microvascular surgery is required for doing this type of work. A long-term evaluation of the results of microlymphatic surgery in obstructive secondary lymphedema is required before judging its potential--especially in view of the fluctuating history of lymphedema--but the results reported are encouraging.

Neurovascular island pedicle flaps for terminal amputations and digital scars

Summary A volar island pedicle flap supplied by double neurovascular bundles is described in the treatment of terminal amputations and digital scars. Its use in selected cases is recommended including also elimination of anisthetic areas in the distal pulp region. Large flaps can be used for extensive digital tip defects and the method is applicable to multiple digital tip injuries.