Necrotising fasciitis involving the periorbita is a devastating infection. Potential outcomes range from severe disfigurement, loss of the eye and even to death. Early recognition is critical, although its initially non-distinctive appearance frequently delays diagnosis and treatment. Herein, the authors have performed a systematic review of previously published cases including clinical features, diagnoses and differential diagnoses, pathological characteristics and management. Periorbital necrotising fasciitis is seen mainly in adults with a female predominance (54%); about one-half (47%) of the patients were previously healthy. The infection can follow local blunt trauma (17%), penetrating injuries (22%) and face surgery (11%), but in about one-third of cases (28%) no cause was identified. Non-specific erythema and localised painful swelling of the eyelids characterise the earliest manifestation of the disease, followed by formation of blisters and necrosis of the periorbital skin and subcutaneous tissues. The causative organism in periorbital infection was mainly β-haemolytic Streptococcus alone (50%), occasionally in combination with Staphylococcus aureus (18%). The overall mortality rate was 14.42%. The main risk factor for mortality was the type of causative organism, since all reported cases of death were caused by β-haemolytic Streptococcus alone or associated with other organisms. Unlike necrotising fasciitis affecting other body sites, there was not a strong correlation with age >50 years or the presence of associated chronic illness. Management of periorbital necrotising fasciitis is then based on early distinction of symptoms and signs and aggressive multidisciplinary treatment. Thus, the delay between initial debridement and initiating parenteral broad-spectrum antibiotic therapy should be considered the most critical factor influencing morbidity and mortality.

Free flap surgery is routine today, yet little is known of its pathophysiology. In this study, the authors evaluated the hemodynamics in different types of free microvascular flaps, by measuring intraoperative transit-time flow. Eighty-six free transplants--21 free TRAM flaps for breast reconstruction, 18 radial forearm flaps for head and neck reconstructions, and 47 muscle flaps for head and neck, trunk and lower extremity reconstructions--were studied. Donor artery flow was highest in the radial artery (mean: 57.5 +/- 50 (SD) ml/min) but dropped (p < 0.001) to one tenth (6.1 +/- 2 ml/min) after anastomosis. The flow was lowest (4.9 +/- 3 ml/min) in the recipient artery of the TRAM flap but, after anastomosis, increased significantly (13.7 +/- 5 ml/min) to the level of the flow in the donor artery. The donor-artery flow in muscle flaps had a mean of 15.9 +/- 11 ml/min, and it significantly increased after anastomosing (23.9 +/- 12 ml/min). Weight-related intake of blood was highest in the radial forearm flap (18.5 +/- 6 ml/ min/100g) and lowest in the TRAM flap (2.5 +/- 1 ml/min/100g). The study showed that blood flow through a free microvascular flap does not depend on recipient artery flow. Even low-flow arteries can be used as recipients, because the flow increases according to free-flap requirements. The blood flow through a free microvascular flap depends on the specific tissue components of the flap.

We used color Doppler ultrasound (US) to study postoperative changes in blood flow in 10 non-innervated free latissimus dorsi (LD) muscle flaps transplanted onto lower extremities. The peak, mean, and minimum velocities, resistance index, and diameter of the pedicle, and the recipient and control arteries were recorded preoperatively and on the 2nd, 5th, and 10th days after surgery. In the pedicle of the transplant, the peak and mean velocities increased but not significantly during the follow-up. The minimum velocity value in the thoraco-dorsal artery was (mean ± SD) 4 ± 5 cm/sec preoperatively, and was in the leg 19 ± 9 cm/sec (P < 0.05) on the 5th and 17 ± 10 cm/sec (P < 0.05) on the 10th postoperative day. The preoperative value of the resistance index decreased from 0.92 ± 0.12 to 0.79 ± 0.08 on the 10th postoperative day (P < 0.05). In the recipient artery, the peak (117 ± 37) and mean (35 ± 16 cm/sec) velocities increased significantly on the 5th postoperative day compared to the preoperative value (79 ± 22 and 14 ± 6 cm/sec, respectively). The minimum velocity increased but not significantly. The resistance index was preoperatively 1.23 ± 0.09 and 0.88 ± 0.16 (P < 0.05) on the 10th postoperative day. This prospective clinical study demonstrates that blood flow in the pedicle and in the recipient artery of a free muscle flap increases after surgery. This phenomenon may be due to loss of vascular tone and decreased resistance after denervation. Increased blood flow helps to keep the microanastomosis open and also promotes wound healing.© 1999 Wiley-Liss, Inc. MICROSURGERY 19:196-199 1999Color Doppler ultrasound (US) is a non-invasive technique providing information on the hemodynamics of blood flow. It can be used to measure vessel patency, the direction and velocity of blood flow, and the resistance index and diameter of vessels. 1-3 The technique can accurately distinguish veins from arteries and detect different vascular pathologies. 4 In free flap surgery, 5 Doppler ultrasonography has been used to follow blood flow in a LD free muscle flap, to detect vessels, 6 and to measure blood velocities after free flap surgery. 7 It has also been used to localize perforators in transverse rectus abdominis musculocutaneous (TRAM) flaps, 8,9 to precisely localize the pedicle of musculocutaneous gluteus maximus flaps, 8 and to monitor the patency of microanastomoses in a microvascular fibula flap. 10In our previous studies 6,7 we used this technique to study vessel patency and blood flow in free muscle flaps operated on 3-5 years earlier. We showed then that flaps with a patent pedicle have more muscle bulk and that bulky flaps on lower extremities are probably due to persistent, vigorous blood flow in the pedicle. 6 Our prospective study showed that blood flow in muscle flaps increases from the 2nd week to the 3rd month after the operation. 7It has been documented that blood flow increases in muscles immediately after denervation, 11 leading to arteriolar vasodilation with increased capillary perfusion. [11][12][13...

Although the free microvascular transverse rectus abdominis musculocutaneous (TRAM) flap is in routine use for breast reconstruction, little is known of its hemodynamics. The purpose of this study was to determine whether any differences exist when the free TRAM flap is anastomosed to the thoracodorsal or internal mammary vessels. The study comprised 25 patients receiving a free TRAM flap for breast reconstruction. The thoracodorsal vessels were used as recipients in 21 patients and the internal mammary vessels were used in 4 patients. Blood flow rate was measured directly in the donor and recipient arteries, and after anastomosis by a transit-time ultrasonic flowmeter (CardioMed). Two- and 3-mm probes were used. The blood flow rate in the donor artery (deep inferior epigastric) before flap dissection was 11 +/- 6 ml per minute (mean +/- standard deviation). The rate was significantly (p < 0.05) lower (5 +/- 3 ml per minute) in the recipient thoracodorsal artery than in the donor, but after transplantation it increased to 14 +/- 5 ml per minute (p < 0.05), attaining the same value as the donor artery. The blood flow rate in the intact internal mammary artery was significantly higher (25 +/- 10 ml per minute) than in the donor and thoracodorsal arteries, but after anastomosis it dropped to the same value (12 +/- 3 ml per minute; p < 0.05) as the donor artery. The intake of blood in TRAM flaps supplied by the intemal mammary artery seems to be no greater than that in free flaps anastomosed to thoracodorsal vessels, although the flow in the internal mammary artery was much higher. The authors concluded that the blood supply in a free TRAM flap is independent of the flow in the recipient artery and that thoracodorsal vessels, although often in a scarred bed and radiated, are as suitable for anastomosing a free TRAM flap as are internal mammary vessels.