Disa Lidman

THE NORMAL HEALING PROCESS OF MICROVASCULAR ANASTOMOSES

The vessel wall regeneration and the inflammatory response in the rabbit femoral artery and vein the first three months after microvascular end-to-end suture anastomosis was assessed histologically. The initial damage consisted of endothelial loss and partial necrosis of media and adventitia. The luminal surface was reendothelialized and the adventitial layer restored by 20 days, but the necrotized part of the media did not regenerate. Instead, the vessel wall diameter was maintained by an intimal hyperplastic response. At the anastomotic site a characteristic slight dilatation was persistent. Consequently, the vessel wall architecture was not restored to the preoperative state after microvascular anastomosis.

Lymphoedema of the lower extremities after surgery and radiotherapy for cancer of the cervix

Fifty-four women were examined to find out the incidence of lymphoedema after treatment of cancer of the uterine cervix. The women had all had total hysterectomy and excision of the pelvic lymph nodes and 53 had also received radiotherapy. The character and severity of problems experienced by the patients in their daily living were assessed by an interview. Twenty-two of the patients (41%) had a unilateral increase in volume of 5% or more in one leg compared with 15 healthy controls in whom the difference between limbs did not exceed 4%. Of the 54 patients 15 (28%) had a slight swelling (> 5% volume increase); 3 (6%) had moderate swelling (> 10% volume increase); and 4 (7%) had severe swelling (> 15% volume increase), which was interpreted as treatment-induced lymphoedema. Twelve (22%) of the patients had lymphoedema that was severe enough to cause symptoms.

Mechanical anastomosis of small arteries and veins with the unilink apparatus: a histologic and scanning electron microscopic study

A new method for mechanical anastomosis of small vessels--the Unilink device--has been tested in 23 rabbits. A total of 81 arterial and venous anastomoses were performed. One of the arterial anastomoses were thrombotized, while the remaining 80 anastomoses were fully patent at 2 or 16 weeks. The repair process at the anastomotic site was very rapid both in arteries and veins. The endothelialization was complete at 2 weeks, but a marked atrophy of the media was noted in the arterial anastomoses. The same phenomenon was observed in the venous anastomosis, but to a much lesser degree. Thrombus formation was extremely rare, and the atrophy of the media did not seem to affect the patency rate. The experiment has confirmed that the Unilink method provides a very safe, fast, and simple way to perform microvascular anastomoses.

Evaluation of Clinical Microvascular Anastomoses- Reasons for Failure

Thrombosis in clinical microvascular anastomoses is attributed to suture errors and utilization of severely damaged recipient arteries. Histopathological specimens from 24 microvascular anastomoses and 77 vessel biopsies from free tissue transfers and replantation cases were analyzed. Suture errors of any note were rare and occurred primarily in replantation cases in which team experience varied and fatigue was common. Recipient artery damage ranged from minimal to severe; clinical analysis confirmed the devastating effect of refractory spasm associated with intramural scarring from previous trauma. Additional studies by microvascular groups are needed to clarify the causes of thrombosis and the healing mechanism of microvascular anastomosis.

Changes in a rat facial muscle after facial nerve injury and repair.

This study describes changes in a rat facial muscle innervated by the mandibular and buccal facial nerve branches 4 months after nerve injury and repair. The following groups were studied: (A) normal controls; (B) spontaneous reinnervation by collateral or terminal sprouting; (C) reinnervation after surgical repair of the mandibular branch; and (D) chronic denervation. The normal muscle contained 1200 exclusively fast fibers, mainly myosin heavy chain (MyHC) IIB fibers. In group B, fiber number and fiber type proportions were normal. In group C, fiber number was subnormal. Diameters and proportions of MyHC IIA and hybrid fibers were above normal. The proportion of MyHC IIB fibers was subnormal. Immediate and delayed repair gave similar results with respect to the parameters examined. Group D rats underwent severe atrophic and degenerative changes. Hybrid fibers prevailed. These data suggest that spontaneous regeneration of the rat facial nerve is superior to regeneration after surgical repair and that immediacy does not give better results than moderate delay with respect to surgical repair. Long delays are shown to be detrimental.

Sitting pressure and perfusion of buttock skin in paraplegic and tetraplegic patients, and in healthy subjects : a comparative study

The distribution of sitting pressure and ability to respond with reactive hyperaemia were studied in a group of paraplegic and tetraplegic patients ( n = 8) with spinal cord lesions and healthy controls ( n = 10) using a pressure sensitive plate and laser Doppler perfusion imager. The results show that the mean sitting pressure of the patients was 9.9 N/cm 2 (left) and 11.7 N/cm 2 (right) compared with 3.5 N/cm 2 controls. The differences were significant on both the left ( p < 0.01) and right ( p < 0.05) sides. The maximum pressure in patients was 42.9 N/cm 2 (left) and 48.7 N/cm 2 (right), and in controls ( p < 0.01). Both groups showed a reduction in skin perfusion in the seat area during sitting compared with unloaded resting, and in the controls it was significantly increased ( p < 0.001 on both sides) during the reactive hyperaemic phase immediately after sitting. Compared with the preload values, the patients showed a similar but slightly weaker picture significant on the right side ( p < 0.05), but not on the left. The hyperaemia was not uniformly distributed, but occurred where the pressure was greater than 2 N/cm 2 . There was no correlation between the amount of reactive hyperaemia and absolute values of sitting pressures. We conclude that tetraplegic and paraplegic patients have significantly higher sitting pressures than normal controls, and that the hyperaemic response in the buttock region in the upright position after pressure load is slightly weaker in the patients, which could be of importance for the development of decubitus ulcers.

Team approach to tibial fracture: 37 consecutive Type III cases reviewed after 2-10 years

During a 10-year period, we managed 35 patients with 37 cases of Type III open tibial fractures, 15 cases within 1 week and 22 as late referrals. In all cases, simultaneous assessment and management by a microvascular and an orthopedic surgeon were mandatory throughout the treatment period. 6 of the 15 acute cases had a primary amputation. Of the remaining 31 cases, limb salvage was possible in 27. 31 flaps, pedicle and microvascular free flaps were used. Major complications occurred in 6 cases, but in 27 cases infection-free solid union was obtained. At long-term follow-up, average 5 years, the function was good or acceptable in 23 cases. We conclude that: (1) patients with Type III tibial injuries should preferably be transferred within a week after injury to a hospital where major reconstructive procedures are commonly performed, (2) early soft tissue coverage is essential in the management of these injuries, (3) unilateral external fixation should be the preferred technique of stabilization, and, finally, (4) plastic surgery expertise is important in management of severe tibial fractures.

The Morphology and Patency of Arterial and Venous Microvascular Anastomoses Throughout the first Post-operative Year

End-to-end microvascular suture anastomoses, 40 arterial and 41 venous, from the rabbits carotid artery and posterior facial vein were harvested at 5 different time intervals (1, 2, 3, 6 and 12 months) post surgery and evaluated with light microscopy. A 100% long-term patency was noted both in arteries and veins. Quantitative measurements of the width of the vessel wall components indicated that a statistically significant temporary hypertrophic response occurred in the arterial intima, culminating in the third month when the width of the vessel wall at the anastomotic level almost doubled the normal. After that the width of the vessel wall again declined but it remained thicker than the adjacent vessel wall at one year post surgery. Among the venous anastomoses, however, the wall thickness at the anastomotic level remained thinner than the adjacent vessel wall throughout the evaluation period. The original vessel wall characteristics are not restored at the anastomotic site with intimal hyperplasia compensating for medial necrosis. Despite these events a technically satisfactory microvascular anastomosis should remain patent for years.

Perfusion of the skin of the buttocks in paraplegic and tetraplegic patients, and in healthy subjects after a short and long load

In patients with spinal cord injuries (n=8) and healthy controls (n=8) the hyperaemic response in the buttock skin after sitting on a hard surface was studied using a laser Doppler perfusion imager. They sat for three minutes (short load), or 15 minutes (long load). An exponential mathematical function was used to compare the mean perfusion during the observed interval. The results showed that preloading perfusion is significantly higher among patients than healthy subjects. In both groups, the microcirculation of the skin increased significantly after loading, and peak perfusion was significantly lower after the short load. The mean perfusion was higher among the patients after both loadings, which suggests that there was stronger ischaemic provocation. The main outcome was that there was a dose-response relation between duration of loading and intensity of reactive hyperaemia, and that patients with spinal cord injuries have greater perfusion before and after loading than healthy controls.

An anastomotic device for microvascular surgery: evolution

A new anastomotic device is demonstrated that is suitable in microvascular surgery for repairing severed blood vessels and inserting vein grafts. Initial pilot studies indicate a 100% patency rate for vessel anastomosis, and a one-year study produced a 96% success rate. However, histological examination revealed notable vessel deterioration with a rigid device. Therefore, an absorbable anastomotic coupler was developed that demonstrates a high patency rate (92%) in both arteries and veins, with substantial absorption of the device by 70 days. Healing at the anastomotic site was qualitatively similar to that obtained with a sutured anastomosis; there was endothelialization by 14 days and absorption of the device by 70 days.