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Objective: To examine the association of low fetal fraction of cell-free DNA (cfDNA) with placental compromise and adverse perinatal outcomes., Materials and Methods: This was a retrospective cohort utilizing a sample of convenience including 639 women undergoing cfDNA screening at our institution from January 2013 to January 2017. Low fetal fraction was defined as less than the 25th percentile. Indicators of placental compromise were examined individually and as a composite outcome, including hypertensive disease of pregnancy, intrauterine growth restriction, abruption, and oligohydramnios. Neonatal outcomes, including preterm delivery, low Apgar scores, and small for gestational age, also were examined. We calculated risk ratios (RR) and 95% confidence intervals (CI)., Results: Low fetal fraction was associated with placental compromise (RR 1.6 [CI 1.1-2.2]), hypertensive disease of pregnancy (RR 1.6 [CI 1.003-2.6]), and preeclampsia with severe features (RR 3.3 [CI 1.2-8.9]). Low fetal faction was not associated with preterm delivery, low Apgar scores, or small for gestational age., Conclusions: Low fetal fraction of cfDNA among asymptomatic women may serve as a predictor of subsequent placental dysfunction and hypertensive disease., (Copyright © 2019 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.)

Objective: To assess the clinical utility of cell-free DNA (cfDNA)-based screening for aneuploidies offered through primary obstetrical care providers to a general pregnancy population., Methods: Patient educational materials were developed and validated and providers were trained. Serum was collected for reflexive testing of cfDNA failures. Providers and patients were surveyed concerning knowledge, decision making, and satisfaction. Pregnancy outcome was determined by active or passive ascertainment., Results: Between September 2014 and July 2015, 72 providers screened 2,691 women. The five largest participating practices increased uptake by 8 to 40%. Among 2,681 reports, 16 women (0.6%) were screen-positive for trisomy 21, 18, or 13; all saw genetic professionals. Twelve were confirmed (positive predictive value (PPV), 75%; 95% CI, 48-93%) and four were false-positives (0.15%). Of 150 failures (5.6%), 79% had a negative serum or subsequent cfDNA test; no aneuploidies were identified. Of 100 women surveyed, 99 understood that testing was optional, 96 had their questions answered, and 95 received sufficient information. Pretest information was provided by the physician/certified nurse midwife (55) or office nurse/educator (40); none was provided by genetic professionals., Conclusion: This first clinical utility study of cfDNA screening found higher uptake rates, patient understanding of basic concepts, and easy incorporation into routine obstetrical practices. There were no reported cases of aneuploidy among cfDNA test failures.Genet Med advance online publication 12 January 2017.

Study Objective: To review our experience with general anesthesia in endoscopic fetal surgery for twin-to-twin transfusion syndrome (TTTS), and to compare fetomaternal outcome before and after protocol implementation., Design: Retrospective impact study., Setting: University-affiliated medical center., Measurements: Data from 85 consecutive patients who underwent endoscopic laser ablation of placenta vessels for severe TTTS were studied. Outcomes were compared in patients before (2000-2007) and after (2008-2012) a change to strict intraoperative intravenous (IV) fluid and liberal vasopressor management. Perioperative parameters (IV fluid administration, vasopressor use, maternal hemoglobin [Hb] concentration); maternal complication rate (respiratory, hemorrhagic); pregnancy outcome; and fetal and neonatal survival were recorded., Main Results: Patients in the early group (2000-2007; n = 55) received 1634 ± 949 mL of crystalloid fluid intraoperatively, compared with 485 ± 238 mL (P < 0.001; Student's t test) given to the late group (2008-2012; n = 30). Maternal pulmonary edema and any respiratory distress were seen in 5.5% and 12.7% of patients in the early group, respectively, and in none of the late group patients (P < 0.05; Chi-square analysis)., Conclusions: A significant risk of maternal respiratory complications exists after general anesthesia for endoscopic fetal surgery. Judicious fluid management significantly decreases this risk., (Copyright © 2014 Elsevier Inc. All rights reserved.)

As many avulsion amputations are incomplete and the vessels remain intact, the immediate pathology and long-term repair process (to 3 months post-injury) of experimentally stretched but unruptured rabbit femoral arteries and veins were examined. In stretched arteries, circumferential skip lesions involving endothelium, internal elastic lamina (IEL) and media occurred frequently and often up to 3 cm from the point of stretch. Medial smooth muscle cells (SMC) were significantly damaged or lost at lesions. Macrophages and neutrophils were found in lesions 1-4 days post-injury. Between 2-4 days, lesions were covered by endothelium and synthetic state SMC appeared in the media. At 1 week, a thin neointima (which persisted to 3 months) covered many lesions. The media at lesions gradually filled with SMC but generally remained disorganised even at 3 months post-injury. Stretching caused tears in vein walls, particularly close to the point of injury. There was no evidence of venous damage or repair in specimens examined 3 weeks and 3 months post-injury.

This study tested the hypotheses that perfusion of cooled skin flaps with established organ preservation solutions improves their viability and that this improvement can be further enhanced by pharmacological manipulation. Rabbit epigastric skin flaps were perfused with different solutions before explantation and stored at 8 degrees C for 6 days. In the first part of the experiment, flap viability was assessed 7 days after reperfusion of the flap via microvascular anastomoses. The different solutions were heparinised blood, University of Wisconsin solution, two of its modifications, EuroCollins solution and a pharmacological mixture containing phosphoenolpyruvate, desferrioxamine, nitrendipine, dextran 70 and a platelet-aggregating factor receptor antagonist (WEB 2170). In the second part, biochemical parameters of skin were measured at various reperfusion times. Adenosine triphosphate (ATP), reduced glutathione (GSH), myeloperoxidase (MPO) and tissue water were assayed at 0, 1, and 24 h after reperfusion. In addition, plasma thromboxane (TXB2) was measured at 0, 30 and 60 minutes after reperfusion. The viability of flaps perfused with the mixture (81%) was significantly higher than that of any of the other groups (39% for controls, 38% for EuroCollins, 13% for UW solution, 27% and 31% for its modifications). ATP levels after reperfusion were higher in the mixture group than in UW-perfused group. GSH levels in the mixture group were also higher than in the UW group, indicating higher level of protection against oxidative stress during reperfusion. There were no differences in MPO levels. Thromboxane levels associated with UW-perfused flaps were significantly higher than those associated with any other perfusion solution. In conclusion, perfusion of a mixture of pharmacological agents targeting specific aspects of ischaemia/reperfusion injury improved the viability of skin flaps stored in the cold for 6 days, whereas standard organ preservation solutions failed to affect significantly skin flap survival.

Because of the small number of inflammatory cells found in skin wounds, it has been considered that foetal sheep are incapable of an adequate inflammatory response. The present study shows that subcutaneous injection of turpentine or carrageenan into foetal sheep consistently excites a severe cellular inflammatory reaction. At 75 days gestation the inflammatory cells are all macrophages. As the foetus develops, polymorphs play an increasing role in the early response to turpentine. By 120 days inflammatory cells are almost all polymorphs as in adult sheep. However the response to carrageenan remains macrophage in type. At all stages of gestation the acute cellular response is followed by development of scar tissue, more pronounced with turpentine than carrageenan. Any proposed intrauterine surgery must allow for the pronounced and prolonged inflammatory response and scar tissue formation caused by persistent inflammatory stimuli in foetal animals.

A study was made of the healing of excised, unsutured and sutured skin wounds in foetal sheep of 75, 90 and 120 days gestation and of wounds in newborn lambs and adult ewes. Foetal and postnatal wounds were found to heal in a very similar way. At each stage of development studied, excised wounds contract rapidly and histological and electron microscope examination demonstrates formation of granulation tissue and its maturation to scar tissue in all types of wound. Examination of polyvinyl sponges 7 and 14 days after subcutaneous implantation confirms the ability of foetal sheep to form vascularised scar tissue. The cellular inflammatory response to wounding is much less prominent in foetal than in postnatal sheep, the number and type of extravascular cells reflecting the changes in blood leucocyte content during development. From a very early stage foetal sheep react to insoluble irritants by the formation of multinucleate giant cells.

Free submandibular gland transfer is potentially the best surgical solution to total xerophthalmia. Experimentally, gland function has only previously been followed for 2 months. This study was designed to investigate the long term effects of free transfer on gland function. Simultaneous creation of experimental xerophthalmia and free microvascular transfer of the submandibular gland to the orbit was completed in 10 rabbits. Two died before the end of the experimental period and the study was based on the remaining eight. Six months after transfer, five of the eight transferred glands were histologically normal and contained healthy neurones and nerve terminals. In these animals, tear secretion in the transfer eye was significantly greater than that of the control eye at 2 (p less than 0.05) and 6 months (p less than 0.02) after transfer. In the transfer eye, tear secretion was also found to have significantly increased from preoperative levels at 2 (p less than 0.05) and 6 months (p less than 0.01). The observed innervation of the transferred glands may play a role in maintaining secretion in the long term.

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.

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.

Silicone tissue expanders were inserted subcutaneously in the buttocks of nine young pigs and gradually inflated to maximum capacity over 5 weeks. On the control side the expanders were left uninflated. Island buttock flaps were then raised, the expanders removed and the flaps spread into the same sites for 10 days. The tissue was harvested. Area measurements and full thickness skin biopsies were taken 10 days after flap inset in order to study the changes in collagen composition and isotypes in the skin layers. Ten days after inset of the flap the expanded skin had a mean 47% increase in surface area, was 9% thinner (from surface to implant), mostly due to thinning of the subcutaneous zone, but was not significantly different in water content, relative to the control skin. The expanded skin had a significant 9.3% increase (p less than 0.01, t test) in collagen content of the dermis. The relative proportions of Types I and III were not significantly changed by skin expansion in either the dermal/epidermal or subcutaneous/capsular zones. It is speculated that tensile factors during expansion stimulate the biosynthetic activity and/or mitotic activity of fibroblasts in the dermis to produce this gain in collagen in the expanded compared with unexpanded tissue.

The rabbit epigastric free flap, subjected to 21 hours of warm (25 degrees C) ischaemia, was used as an experimental model to test the ability of two endothelium-dependent vasodilators, calcitonin gene-related peptide (CGRP) and carbamyl beta-methylcholine chloride (MCh, bethanechol chloride, the stable acetylcholine analogue) to improve flap viability. After the period of ischaemia, flaps were infused intra-arterially with either Hanks balanced salt solution (controls), CGRP or MCh for 30 minutes, and received additional intravenous boluses of these drugs at 2 and 32 minutes after revascularisation. The area of flap surviving improved significantly (p less than 0.025) from 39.9% (n = 18) for controls to 70.2% (n = 14) for CGRP treatment at 2 micrograms/kg, but was unchanged at 47.1% (n = 14) for MCh treatment at 50 micrograms/kg. Both CGRP and MCh significantly increased blood flow (p less than 0.05) resulting in 34% lower peripheral resistances compared with controls. These results suggest that CGRP has considerable clinical potential for the salvage of ischaemic flaps. CGRP must have several, as yet undefined, beneficial effects on the ischaemic tissue, since MCh invoked a vasodilatory response but failed to salvage ischaemic flaps.

Free submandibular salivary gland transfer was investigated as a method of treatment for xerophthalmia. Xerophthalmia was created in rabbits by surgical removal of the lacrimal gland and the incidence of corneal ulceration was seen to correlate with the decrease in tear secretion. Microvascular transfer of the submandibular salivary gland to drain saliva into the conjunctival fornix prevented the development of corneal ulceration in 63% of the cases.

In 13 dogs, experimental obstructive lymphoedema of the lower limb was created by combined radiotherapy and radical groin dissection. Six months later, when the degree of lymphoedema was stable, the lymphatic obstruction was bridged by microvascular insertion of a free omental graft. Six months after grafting, circumferential measurements indicated a statistically significant 38% reduction in the magnitude of lymphoedema. Biopsies showed the omental grafts were alive but contained much fibrous tissue. Lymphatic vessels were identified in 10 of 11 biopsies but connections between these lymphatics and lymphatics proximal to the graft could not be demonstrated by either lymphangiography or dye-injection techniques. The findings indicate that experimental obstructive lymphoedema in the dog can be reduced significantly by insertion of a vascularised omental graft. However, it could not be established that improvement was due to union of graft lymphatics with those of the lymphoedematous limb, although this union may have consisted of lymphatics too small to be demonstrated.

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.

Using an experimental model in the rabbit, the importance of direct cutaneous vessels for skin flap survival in skin avulsion injuries with, and without, a crushing injury has been investigated. The results are presented and possible application to the human situation discussed.

Thumb reconstruction requires accurate functional and esthetic approximation to the original. Accepted methods generally have some deficiencies, particularly in appearance, and frequently the secondary morbidity is unacceptable. A method of thumb reconstruction with the use of an iliac crest bone graft and a free neurovascular "wrap-around" flap from the big toe is described that combines the attributes of previous methods without their secondary morbidity.

Vascularized tendon grafts were compared with nonvascularized tendon grafts in a primate experimental model. In four monkeys, seven vascularized extensor hallucis longus grafts were placed in the foot's digital fibroosseous canal and these were compared with eight nonvascularized tendon grafts similarly placed in the opposite extremities. The juncture techniques and postoperative protocols were identical for both tendon groups. All tendons were explored 5 months after insertion. The vascular pedicle was patent in all vascularized tendons. Three tendon ruptures occurred in nonvascularized tendons and only one rupture occurred in a vascularized tendon. The digits with vascularized tendons demonstrated a significantly better simulated total active motion (117 degrees versus 128 degrees, p less than 0.05) than digits with nonvascularized tendons. The difference was even more significant when a localized tenolysis of the proximal juncture of the tendon graft was performed (215 degrees versus 138 degrees, p less than 0.01). This study supports the concept that vascularized tendon grafts may be advantageous in scarred tendon beds.

Microvascular repairs of 50 rabbits' femoral arteries averaging 0.9 mm in diameter gave an immediate patency rate of 100 per cent and a follow-up patency rate of 98 per cent after 3-41 days. The patency rate of 50 veins averaging 1.1 mm in diameter was 98 per cent immediately after surgery and 80 per cent after 3-41 days. No anticoagulants or antispasmodics were used. An additional 25 vein repairs with sufficient additional sutures to ensure more accurate apposition of the vein edges resulted in 100 per cent immediate patency and 92 per cent patency when examined during the 2nd week, the period which reveals the truest patency rate. Technical adequacy of the microvascular repair is the most important factor in ensuring final patency.

Rabbit epigastric free flaps were subjected to ischaemia at 25 degrees C for 24 hours. At the time of revascularisation the flaps were infused intra-arterially with one of the following: Hanks balanced salt solution (control), the high energy phosphates PEP/ATP, the thromboxane synthetase inhibitor dazoxiben hydrochloride, the free radical scavenger SOD and a combination of all these agents (treated groups). Control ischaemic flap survival at post-ischaemia day 7 was 23.5%, while the other treatments resulted in improved flap survival of 43.5% (p less than 0.025), 23.5% (not significant), 38.6% (p less than 0.05) and 35.7% (p less than 0.05) respectively. None of these agents improved post-ischaemic blood flow significantly. These results would support the use of PEP/ATP or SOD in the clinical treatment of failing ischaemic skin flaps but do not support the use of dazoxiben hydrochloride.

Cooling to 6-7 degrees significantly increases ischaemic tissue survival to 48 and, probably, 72 hours. Inflammatory changes develop in direct proportion to the duration of the cold ischaemia time. The skin and vessels within the flap appear to be minimally affected by cold ischaemia while fat and muscle demonstrate significant necrosis, inflammation and ultimate fibrosis. Very little, if any, muscle survives the ischaemic insult studied in this model.

This experimental study investigated the problem of covering bare bone adequately in the oral cavity to provide a stable, functionally acceptable reconstruction. In eight dogs, intraoral mucosal defects were created whilst preserving the mandibular arch. The defects were reconstructed with a microvascular jejunal patch. Six animals had their reconstructions stressed postoperatively by the administration of irradiation and by feeding solid food. Two control dogs did not receive irradiation. Grafts were assessed clinically and histologically for 6 months. Rapid mucosal healing occurred in seven of eight dogs. The grafts conformed well to the mandibular contour and were tolerant of postoperative radiotherapy and the chewing of solid food. Structural integrity of seven grafts was maintained although subtotal villous atrophy occurred in irradiated grafts and to a lesser extent in control grafts. In one animal whose graft mucosa sloughed, the wound was re-epithelialized from the adjacent buccal mucosa. Microvascular jejunal patches therefore provided a durable, functionally adequate reconstruction of the mouth floor.

In tendon grafting the weakest area is the junction between the grafted tendon and bone. In dogs a strong union between tendon and bone can be produced by threading the flexor carpi radialis tendon through a hole drilled in the radius. In experimental repair of canine flexor tendons, 3 weeks after operation the strength of the union between a composite bone-tendon graft prepared in this way is double that of the bone-tendon junction of a conventional graft. Use of prefabricated bone-tendon grafts should permit earlier postoperative movement and limit formation of adhesions between a tendon graft and its bed.

Four cases are described in which the opposite ring finger was used for finger reconstruction in transmetacarpal hand amputations. Thumb reconstruction was required in three of these four cases. This was achieved by hallux transfer, tube pedicle combined with an innervated first foot web neurovascular free flap, and second toe transfer respectively. In the fourth case, where a thumb was not required, double finger reconstruction was performed by the use of a second toe combined with a ring finger. This case highlights the limitations of the second toe for finger reconstruction, particularly in achieving palmar-digital grip. The advantages of the ring finger are length and mobility, especially sophisticated intrinsic muscle movement, sensory capacity, strength, wider span, and esthetic excellence.

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.

Seventy femoral arterial avulsions with interpositional microvenous graft repairs were performed in rabbits and were divided into three groups. In Group A clamps were reapplied for 15 minutes with an overall patency rate of 97% after 3 weeks. The overall patency rate in Group B with 30 minutes reclamping was 93% three weeks later. Group C without clamping served as Controls and a 100% patency rate was achieved. The position of the microclamps, static blood in the region of the anastomoses and in the microvenous grafts as well as the time of reclamping up to 30 minutes did not influence the patency rate in damaged vessels after sufficient resection of injured vessel walls. The results of this experiment suggest that if necessary clamps can be reapplied safely in the clinical situation for up to 30 minutes after microvenous grafts have been completed to enable the microsurgeon to perform further dissection in a bloodless field.

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.

A 5 cm length of 2 mm internal diameter (i.d.) synthetic, expanded polytetrafluoroethylene (PTFE, or Gore-Tex) vascular graft was used to connect 25 rabbit inferior epigastric flaps to the contralateral femoral vessels. In 15 animals an expanded PTFE graft connected the opposite femoral artery to the flap while the ipsilateral venous drainage remained intact. In the remaining 10 animals an expanded PTFE graft was used to replace the venous drainage of the flap and connected to the opposite femoral vein while the ipsilateral femoral artery supplied the flap. Flap survival and graft patency were evaluated over 3 weeks. Ten of 15 flaps with intra-arterial grafts survived at 3 weeks (67%). Only 27% (4/15) of their supplying grafts remained patent for 3 weeks, although 67% (10/15) were patent at 10 days. All 10 flaps, where expanded PTFE grafts replaced venous outflow, failed within 36 hours. At exploration these grafts were thrombosed or collapsed. In conclusion, currently available 2 mm (i.d.) expanded PTFE vascular graft cannot maintain patency in a low blood flow circulation supplying an isolated free flap.

Vascularised and non-vascularised perichondrial grafts from the rabbit's ears were transplanted to the lower abdominal wall and their cartilage formation compared. Similar results were found in both groups. Presence of blood and spontaneous revascularisation of non-vascularised grafts as well as self limitation of cartilage formation in immediately revascularised grafts seem to be the reason for these results.

One hundred and five microvenous grafts were carried out during three periods of time. Forty-five were performed in 1971, 25 were performed in 1975 and 35 were performed in 1979. The rabbits weighed 2 to 2.5 kg and a standard technique was followed by inserting a 1 cm vein graft after creating a defect of 0.5 cm in the femoral artery, taking the graft from the femoral vein on the same side. Exploration was carried out from 1 to 21 weeks at weekly intervals. The patency rate in Series I (1971) was 71 per cent, whereas the patency rate in Series II (1975) was 96 per cent and in Series III (1979) was 100 per cent. The scanning electron microscope showed that in the short term there was no narrowing of the lumen, nor any microaneurysm formation as reported previously by Buchler and Buncke (1979).

The use of a specially designed tissue tonometer in 17 lymphoedema patients, who were treated with multiple lymphaticovenous anastomoses, with a follow-up period of up to 18 months, gives a quantitative measurement of "softness" and correlates well with their subjective feeling. It would appear to complement limb volume and circumferential limb measurements.

A study was undertaken to determine the adequacy of vascularised jejunum to provide stable mucosal cover over a non-biological mandibular substitute. Employing a canine model, composite intra-oral bone-mucosal defects were created and reconstructed with a metal plate covered by a microvascular jejunal patch. These were followed for six months and were assessed clinically, histologically and radiologically. Rapid mucosal healing occurred in all cases. The autografts conformed to the contour of the prosthesis and adequate tongue mobility was preserved. All mandibles remained stable throughout the follow-up period. Histologically, short villi covered the jejunal grafts to three months whilst at six months both normal and abnormal jejunal mucosal morphology was evident.

After developing some basic techniques of lymphaticovenous anastomoses in 60 dogs, a further study of these anastomoses in the greyhound was performed with a patency rate of 74 per cent a 1 week and 66 per cent between 6 and 12 weeks. Points of technique and causes of failure are discussed. The use of this method in the treatment of early secondary lymphoedema is mentioned.

The pig buttock flap model was used firstly, to compare changes in expanded axial skin flap area with control flaps prior to flap elevation and 3 or 4 months post-flap inset and, secondly, to compare the thickness of expanded and control flaps at elevation and for 3 to 6 months post-flap inset. Following 5 weeks' expansion and prior to elevation, the expanded tissue had gained a significant 63.3% mean increase in area compared with the control tissue (p less than 0.01). Immediately post elevation and inset, the expanded flaps were still significantly larger than the control flaps by a mean 29.8% (p less than 0.01) but had lost 56% of the original area gained. Little change in area occurred in the 3 months post-flap inset as the expanded flaps were still a mean 23.4% larger than the control (p less than 0.01). Dermal and cellular non-keratinised epidermal layers thickened markedly in expanded skin compared to control skin. Following elevation and inset of the flaps, both dermis and epidermis thickened in expanded and control flaps.

A neuropeptide known as calcitonin gene-related peptide (CGRP) has been shown to have vasodilatory properties in the rabbit epigastric island flap of almost equivalent potency to prostacyclin. The latter is currently regarded as the most potent vasodilator yet to be isolated. CGRP, with its longer-lasting effect in blood and its ability to overcome noradrenaline-induced vasospasm, may be promising for use during or after ischaemic flap transfer or replantation. Another known vasodilatory peptide, atriopeptin, was not as potent in the microvascular bed of the cutaneous flap as in major blood vessels.

Twenty toe-to-hand transfers in 17 patients with an average follow-up of 54 months have been reviewed to quantify hand function and donor morbidity. Eleven toe-to-thumb and nine toe-to-finger procedures were performed. Surgical and follow-up data were available for all patients. Twelve patients (14 procedures) were reviewed in detail, with particular attention given to foot and hand function. Total active motion after toe-to-thumb transfer was 48 degrees and 106 degrees after toe-to-finger transfer. Two-point discrimination was less than or equal to 15 mm in 13 digits (65%). Grip and pinch power were related to the number of digits present on the reconstructed hand and to the presence or absence of functioning thenar muscles. Eleven of 12 patients can walk and run normally (mean of 5 years after surgery). Six (50%) cannot wear thongs or heavy boots, but all can wear normal shoes. The transferred great toe decreased in volume by an average of 10% over the years since the operation. Transferred toes became useful digits in the hand, and foot morbidity was minor and not progressive.

Toe-to-hand vascularized joint transfers in four children were reviewed 6 to 8 years after operation (average, 6.6 years). Two children had vascularized metatarsophalangeal (MTP) joints. Both children have near normal active range of motion. The transferred epiphyses have provided a major contribution to digital growth. The other two children had second toe proximal interphalangeal (PIP) joints transferred to damaged hand joints. Active PIP joint extension has been disappointing, and the overall growth contribution of the transferred epiphysis has been small. We conclude that MTP to metacarpophalangeal vascularized joint transfer can provide painless, functional, stable motion, with near normal growth potential, and the usefulness of toe PIP to hand PIP joint transfer is limited by the inability to achieve good active extension and limited growth potential.

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.

Controlled expansion is a technique that increases the area of local tissue available for reconstruction. An extension of this is to expand free flaps prior to elevation, thereby increasing their area. This has been particularly useful in children where there may be insufficient tissue available at free flap donor sites. Four children have had extensive cutaneous defects of the lower limb reconstructed with expanded parascapular free flaps. Measurements indicate an approximate doubling in skin area. There has been normal growth of the affected limbs and there has been no donor site morbidity. Apart from small areas of narrow marginal necrosis at the tip of the flaps in the first three cases, which were of no consequence, healing at the recipient site was complete.

Obstructive lymphedema is a pathologic condition resulting in the accumulation and stagnation of serum proteins in the lymphatics and interstitial spaces. In a canine model of obstructive lymphedema, one limb was rendered lymphedematous, and various biochemical parameters were determined in this and an unaffected control limb. Both lymph and interstitial fluid had significantly decreased acid proteinase activity (comprising mostly cathepsin D-like enzymes) and neutral proteinase activity (comprising metallo, sulfhydryl, and serine proteinases, and collagenase). Possible reasons for these decreases could be: (1) saturation of macrophages and their surrounding environment with whole or partially digested proteins, or (2) elevation in the levels of circulating inhibitors like alpha 2-macroglobulin. The lymphedematous skin was significantly thicker than control skin and had elevated levels of collagen. However, unlike some fibrotic conditions, the relative proportions of types I, III, and V collagen, as determined by pepsin solubilization and neutral salt fractionation of the collagen fibrils, were similar to those found in normal skin. It is speculated that a decrease in the breakdown of collagen by collagenase and a continuing synthesis of collagen by fibroblasts led to an imbalance in favor of collagen deposition in the skin.

Computer programmed multi-image presentations enhance considerably the visual content of an audiovisual presentation. A multi-image production provides ample opportunity to present the pre- and post-operative images simultaneously, enabling the audience to compare and comprehend the results with ease. With more than one image the natural sequence of dissection details can be shown, resulting in continuity of thought. The dissolve mechanism offsets any visual fatigue of the audience. The films contribute animation sequences which cannot be demonstrated well on slides. A presentation of all material provides the lecturer with maximum control with the minimum of effort, utilising one button. A computer programmed multi-image production is a complex medium of audiovisual presentation and needs a great deal of time and experience and is not to be lightly undertaken. With the increased number of slides, images and projectors the margin for error is small. Careful slide assembly and repeated rehearsals are the keys to success. At the moment, its use is recommended for special lectures only with adequate consideration being given for the increased expense of production.

The current study investigated the efficacy of deferoxamine for treating secondary ischaemia due to venous obstruction in a rodent epigastric pedicle flap model. Rats receiving one dose of the free radical scavenger and iron chelator deferoxamine (150 mg/kg) intravenously prior to reperfusion had a mild improvement in flap survival: 46% in controls, 77% in deferoxamine-treated. This was statistically significant at p less than 0.05 (chi 2 = 5.2). This suggests that free radicals are partly involved in the mechanism of ischaemia/reperfusion injury in secondary ischaemia, as has been previously demonstrated for primary ischaemia (Angel et al., 1986b). Supporting biochemical evidence will be necessary to understand better the mechanisms involved in secondary ischaemia.