[Current Perceptions of Lipofilling on the Basis of the New Guideline on "Autologous Fat Grafting"]. / Aktuelle Erkenntnisse zur Eigenfett Transplantation anhand der neuen Leitlinie "Autologe Fetttransplantation".

Introduction: Autologous fat transfer has recently become an increasingly popular surgical procedure and comprises harvesting, processing and transplantation of adipose tissue, as well as professional follow-up care. This method, as a surgical procedure, can be utilised for trauma-, disease- or age-related soft tissue volume deficits and soft tissue augmentation. As usage is increasing, but the variables of fat harvest, specific indications and fashion of fat transfer are poorly defined, there is a great demand for development of a guideline in the field of reconstructive and aesthetic surgery. Methods: All relevant points were discussed within the scope of a consensus conference including a nominal group process of all societies involved in the procedure and ratified with a strong consensus (>95%). Literature from the standard medical databases over the last 10 years was retrieved, studied and specific guidelines were concluded. Results: Consensus was achieved among all professionals involved on the following points: 1. definition 2. indication/contraindication, 3. preoperative measures 4. donor sites 5. techniques of processing 6. transplantation 7. follow-up care 8. storage 9. efficacy 10. documentation 11. evaluation of patient safety. Conclusion: Definite indications and professional expertise are paramount for autologous fat tissue transfer. Successful transfers are based on the use of correct methods as well as specific instruments and materials. Autologous adipose tissue transplantation is considered to be a safe procedure in reconstructive and aesthetic surgery, due to the low rate of postoperative complications and sequelae.

Pre-expanded ultra-thin supraclavicular flaps for (full-) face reconstruction with reduced donor-site morbidity and without the need for microsurgery.

BACKGROUND: The expanded supraclavicular island flap, as described in 1997 by the senior author (Pallua), is a useful tool for total facial reconstruction, providing satisfactory results without microsurgical prefabrication. The authors report the use of this technique in 12 patients requiring large flaps who presented with extensive facial scarring that had been previously reconstructed using disfiguring, pigmented skin grafts. METHODS: On the basis of their anatomical dissection studies and knowledge of the constant anatomy of the supraclavicular artery and two draining veins, the authors carefully inserted tissue expanders under the supraclavicular island flaps. After the flaps were expanded, all scars were removed and the covering flaps were transferred into place. Sixteen pre-expanded supraclavicular island flaps were used in 11 patients. RESULTS: There were no complications. CONCLUSIONS: The authors present a method of facial reconstruction that has the advantages of creating a large amount of thin tissue of both good color and texture, without the disadvantages of donor-site morbidity, lengthy operative time, and high cost. In their opinion, this is the method of choice for total facial reconstruction.

Preadipocyte-loaded collagen scaffolds with enlarged pore size for improved soft tissue engineering.

Extended soft tissue defects after extensive deep burns or tumor resections are still an unresolved problem in plastic and reconstructive surgery. There is a clinical need for an adequate solution to this problem but currently, no adequate implant material is available for the correction of these defects. Since the autologous transplantation of mature adipose tissue gives poor results, this study explores the advantages of using human preadipocytes in collagen sponges for tissue reconstruction purposes. Human preadipocytes of young adults were isolated, cultured, seeded onto collagen sponges with uniform pore size, and implanted into immunodeficient mice. After 24 hours of incubation in vitro and after explantation at 3, 8, and 12 weeks, sponges were examined for macroscopic appearance, weight, thickness, histology, immuno-histochemistry, and ultrastructure. We find good penetration of cells into the scaffold, layers of adipose tissue, and new vessels on all grafts while controls appear unchanged. These results are promising for improving the reconstruction of soft tissue defects.

[The burned hand. A computer-assisted study of late function of 67 burned and operated hands]. / Die verbrannte Hand. Eine computergestützte Untersuchung der Spätfunktion von 67 thermisch verletzten und operierten Händen.

A good functional outcome of the hand is important in the rehabilitation of severely burned patients. The aim of the study was to evaluate the late functional outcome of deeply burned hands using a computer aided system and to correlate the function with the distribution of the hand burns. Over a 12-year-period 378 patients whose acutely burned hands had been operated on at the burn center of the university hospital Aachen were invited to a follow-up examination. 67 burned and operated hands were evaluated 57 (3-364) months after the burn by the computerized evaluation system EVAL. Active flexion and extension, grip strength, pinch (key, 3-tip and 2-tip), moving 2-point sensitivity and the pattern of skin grafts and scars were assessed. The use of the hand in daily activities was evaluated by a questionnaire. The hands were classified in 4 groups according to the burn pattern: I: patchy burns (total < 12 cm2), II: confluent dorsal burns, III: confluent palmar burns, IV: mutilating burns. Good results were found in group I (n = 25), comparable to normal hand function. In group II (n = 25) there was a significant loss of total active flexion with preserved strength. Increased extension lag and impaired grip strength characterized group III (n = 8). Late functional results in group IV (n = 9) depended on the reconstructive procedure. Between the 4 groups there were significant differences in function. The results were well correlated to the burn pattern and its extent according the classification.

Magnification of the pore size in biodegradable collagen sponges.

In tissue engineering cells are often combined with a carrying structure with collagen being a suitable material to form a 3D-scaffold. A process to manufacture collagen sponges with an adjustable and homogeneous structure has been developed at the Helmholtz-Institute. Using this process, collagen suspensions are frozen directionally and subsequently vacuum-dried. One clinical application in which these scaffolds can be used is soft tissue reconstruction. Various soft tissue defects require an adequate replacement, e.g. in the case of severe burn wounds, or after tumour resections. Collagen (type I) sponges, which are cultured with preadipocytes, may be used to regenerate such defects. In this case, pore sizes of approximately 100 microm are desired to allow a complete differentiation of preadipocytes into adipocytes. Based on known technology to manufacture collagen sponges with an adjustable and homogeneous pore structure, research on the increase of pore size beyond the previous limit of 40 microm was necessary in order to enable soft tissue replacement. A scaffold with an average pore size of 100 microm was obtained.

Influence of different biodegradable carriers on the in vivo behavior of human adipose precursor cells.

The correction of soft-tissue defects presents a challenge in plastic and reconstructive surgery. The implantation of isolated and culture-expanded adipose precursor cells is a solution to this problem because these cells differentiate into adipocytes when implanted in vivo. Appropriate scaffolds are needed in soft-tissue engineering to allow the differentiation of precursor cells. The optimal carrier needs to be defined. In this study, human preadipocytes were isolated and cultured. Three different carrier materials were seeded with 106 preadipocytes each and implanted in 42 nude mice. Sponges and nonwoven carriers based on hyaluronic acid modified by esterification (HYAFF 11) were compared with collagen sponges. Scaffolds without cells served as negative controls in the same animal. After 3 and 8 weeks, the grafts were explanted. Macroscopic appearance, weight, thickness, microscopy, immunohistochemistry, and TEM (scaffold structure, cellularity, penetration depth of the seeded cells, vascularization) were assessed and evaluated for differences in scaffold-cell interactions.Preadipocytes differentiated earlier in vitro when attached to HYAFF 11 scaffolds than to other carrier materials. Macroscopically, all preadipocyte constructs were yellowish and well vascularized, and the controls were white and avascular. Vessel formation was more pronounced around mature adipocytes. Microscopically, HYAFF 11 constructs showed a higher cell density than collagen constructs. The pores of the sponges contained more differentiated adipocytes than the nonwoven carriers, whereas the undifferentiated preadipocytes were more numerous in the nonwoven material. Penetration of adipose precursor cells was deeper and more homogeneous in HYAFF 11 scaffolds. Electron microscopy demonstrated well-differentiated adipocytes and large amounts of extracellular matrix in HYAFF 11 sponges.HYAFF 11 sponges supported the expansion and differentiation of the adipose precursor cells. This carrier is superior to the nonwoven carrier with regard to adipocyte differentiation and superior to the collagen sponge with regard to cellularity. This is a promising method for the reconstruction of soft-tissue defects. Modifications of the scaffold (larger pore size and coating with adipogenic factors) will be examined in further experiments.

Two-year histological outcome of facial lipofilling.

Although there are numerous clinical reports relating to the injection of adipose tissue fragments, only few histological assessments of the histology of these grafts in late follow-up have been made. The authors report a case of adipose tissue harvested with a sharp cannula using low-pressure suction and injection in the lower eyelid areas with subsequent sagging of the graft, although maintenance of volume, after 2 years. The operative corrective procedure consisted of a lower blepharoplasty and removal of the sheathed graft. Histology showed extended oil cysts and a surrounding capsulelike structure. The volume of the graft consisted mainly of oil cysts, and not healthy adipose tissue. The conclusion is that the harvesting procedure damages fragile adipocytes. The outcome of adipose tissue injection thus remains unpredictable. The only reliable guarantee for a good long-term outcome after lipofilling is a specimen biopsy showing healthy adipose tissue.

Hyperbaric oxygen treatment in deep frostbite of both hands in a boy.

UNLABELLED: An 11-year-old boy in good general health conditions suffered deep frostbite on six fingers while he was working without gloves as a beater during a hunt in Poland at an outdoor temperature of -32 degrees C over a 4 h-period. Three days later he was first seen by a physician who planned to amputate the affected fingers. The patient was transferred by his family to our University Hospital in Aachen, Germany. We found third degree frostbite on four fingers of the right and on two fingers of the left hand. Because of the late beginning of the therapy, the patient was treated by HBO(2) according to the Marx-schema for problem wounds (2,4 bar, total time at depth: 90 min, alternations of 100% O(2) and air breathing). HBO(2)-treatment was repeated daily for 14 days. No adverse events were recorded during the course of therapy. A total recovery of the severe frostbite was observed after 14 days of HBO(2)-treatment. Twenty-eight months after the injury the patient reports fully regained sensibility and no pain. The plain X-ray after this period showed no premature closure of the epiphyses or sclerosis of the metaphyses. CONCLUSIONS: Because of the low risk associated with HBO(2), and its potential therapeutic efficiency, HBO(2) should be recommended as adjunct therapy in the treatment of deep frostbite.

Life threatening burn injuries on holidays: problems of primary care, homeland referral and treatment at a domestic burn centre.

Life threatening burn injuries during vacations abroad raise special problems. Depending on the infrastructure of the country, adequate medical care can be delayed and communication between the patient and the medical staff is frequently impossible due to language barriers. Often the patient finds himself in a critical condition, isolated from supporting relatives and financial difficulties may occur. By summarising three cases referred to our centre, we aim to emphasise particularities of the primary management of burned victims at foreign hospitals, their transport, and following therapy at a domestic burn unit. Primary shock treatment and vital surgical interventions, e.g. escharotomy or treatment of the concomitant trauma, are subject to the facility of the hosting country. After management of the acute phase and initiation of local wound treatment, the next step should be to stabilise and prepare the patient for transport. Aeromedical transportation with physician attendency, as well as contact with a domestic burn centre can be established via responsible organisations. At the domestic hospital, every burn victim from abroad deserves special attention. Wound colonisation with different bacterial species or fungi than the usual spectrum of the centre and the risk of crossinfections should be taken in account of the treating medical team. An structure plan for appropriate and continuing surgical treatment is necessary to prevent deterioration of the patient's condition and to optimise wound closure with autologous skin grafts or allogenic materials.

Human preadipocytes seeded on freeze-dried collagen scaffolds investigated in vitro and in vivo.

Currently, there is no adequate implant material for the correction of soft tissue defects such as after extensive deep burns, after tumor resection and in hereditary and congenital defects (e.g. Romberg's disease, Poland syndrome). The autologous transplantation of mature adipose tissue has poor results. In this study human preadipocytes of young adults were isolated and cultured. 10(6) preadipocytes were seeded onto collagen sponges with uniform 40 microm pore size and regular lamellar structure and implanted into immunodeficient mice. Collagen sponges without preadipocytes were used in the controls. Macroscopical impression, weight, thickness, histology, immunohistochemistry (scaffold structure, cellularity, penetration depth of the seeded cells) and ultrastructure were assessed after 24 h in vitro and after explantation at 3 and 8 weeks. Preadipocytes penetrated the scaffolds 24 h after seeding at a depth of 299+/-55 microm before implantation. Macroscopically after 3 and 8 weeks in vivo layers of adipose tissue accompanied by new vessels were found on all preadipocyte/collagen grafts. The control grafts appeared unchanged without vessel ingrowth. There was a significant weight loss of all grafts between 24 h in vitro and 3 weeks in vivo (p < 0.05), whereas there was only a slight weight reduction from week 3 to 8. The thickness decreased in the first 3 weeks (p < 0.05) in all grafts. The preadipocyte/collagen grafts were thinner but had a higher weight than the controls at this point in time. The histology showed adipose tissue and a rich vascularisation adherent to the scaffolds under a capsule. The control sponges contained only few cells and a capsule but no adipose tissue. Human-vimentin positive cells were found in all preadipocyte/collagen grafts but not in the controls, penetrating 1188+/-498 microm (3 weeks) and 1433+/-685 microm (8 weeks). Ultrastructural analysis showed complete in vivo differentiation of viable adipocytes in the sponge seeded with preadipocytes. Formation of extracellular matrix was more pronounced in the preadipocyte/collagen grafts. The transplantation of isolated and cultured preadipocytes within a standardised collagen matrix resulted in well-vascularised adipose-like tissue. It is assumed that a pore size greater than 40 microm is required, as preadipocytes enlarge during differentiation due to incorporation of lipids.

Procalcitonin--a sepsis parameter in severe burn injuries.

Procalcitonin (PCT) levels increase in patients with systemic infections; the highest levels have been found in sepsis. This study tested whether plasma procalcitonin level was related to sepsis, CRP, burn size, inhalation injury or mortality in severely burned patients over the entire clinical course. In 27 patients with 51 (20-91)% TBSA, PCT was measured three times weekly from admission over the entire course of stay in a single ICU. Daily scoring by the "Baltimore Sepsis Scale" was performed. The patients were assigned to three groups depending on the clinical course and outcome: A = no septic complications, B = septic complications-survivors, C = septic complications non-survivors. PCT levels were elevated slightly at admission (mean 2.1 ng/ml) except in three patients who suffered electrical burns (mean 15.7 ng/ml). PCT peak levels correlated well with the Scoring values (r = 0.84) while CRP did not (r = 0.64). Peak PCT levels were significantly higher (p < 0.005) in septic patients (B and C) who averaged 49.8+/-76.9 ng/ml, than in non-septic patients (A) who averaged peak levels of 2.3+/-3.7 ng/ml. The highest PCT levels were found immediately before death (86.8+/-97 ng/ml). Seven patients had an inhalation injury 3rd degree. In these patients at 24 h postburn, there was no relationship between PCT levels and inhalation injury but during the later days postburn there were significant differences in PCT levels in patients with versus without inhalation injury. All patients with inhalation injury 3rd degree developed septic complications. There was no positive correlation between the PCT-admission-levels and the TBSA, but there was a positive correlation between the TBSA and the mean peak PCT levels during the later days postburn (r = 0.73; p < 0.05). The cut-off value of 3 ng/ ml we found reliable to indicate severe bacterial or fungal infection. PCT values over 10 ng/ml increasing over the following days were found only in life-threatening situations due to systemic infections. The individual course of PCT in one patient is more important than absolute values. PCT presented in this study as a useful diagnostic parameter in severely burned patients.

[Early and late treatment of iatrogenic injection damage]. / Früh- und Spätbehandlung iatrogener Injektionsschäden.

Extravasation injuries can result in extensive soft-tissue defects. On the cellular level there are five different pathophysiological mechanisms. Early treatment (surgical removal of the extravasated material within 24 h) and late treatment (debridement and coverage) are different. Thirty-two patients who suffered a significant extravasation were treated surgically by the Department of Plastic Surgery between 1989 and 1997. In 8 patients, referred within the first 24 h, the extravasated material could be removed by saline flushout. None of these patients developed soft-tissue defects or skin necrosis. The other 24 patients were referred late (mean 19 days after the injury). Patients with defects of the dorsum of the hand or cubital fossa area who underwent debridement, temporary wound coverage and skin grafting (n = 11) presented complete healing 52 days after the referral. Defects of the same regions covered by a flap after debridement (n = 6) healed within 14 days. The healing time of defects of the forearm (n = 2) and dorsum of the foot (n = 5) was a mean of 15 days after skin grafting. Cytotoxic and osmotically active substances should be removed by saline flushout within 24 h. In defects of the dorsum of the hand and cubital fossa, early debridement and coverage with an adequate flap should be performed.

Treatment of irreversible lesion of the radial nerve by tendon transfer: indication and long-term results of the Merle d'Aubigné procedure.

Irreversible radial nerve paralysis should be treated by tendon transfer reconstruction to improve wrist and finger extension and stabilization of the thumb joints. Many different techniques and modifications are known and used. A total of 43 patients, all of whom underwent the Merle d'Aubigné procedure, were examined in a long-term follow-up study. Short-term and long-term subjective and objective results were evaluated. The improvement of the motions between initial and follow-up examinations could be demonstrated. Thirty-eight patients were able to return to their former jobs. Interestingly, the majority of the patients were able to move their fingers separately. This finding could be proved by the electromyography and explained by the counteracting flexor tendons. The overall findings indicate that the Merle d'Aubigné procedure is an excellent and reliable tendon transfer method.

The tuberous breast deformity: classification and treatment.

To date there are many descriptive terms for the tuberous breast deformity but there is no widely accepted nomenclature. A retrospective study was undertaken of 68 tuberous breasts and the operative corrections performed. The deformities were classified into four types. Type I (hypoplasia of the lower medial quadrant), type II (hypoplasia of the lower medial and lateral quadrants, sufficient skin in the subareolar region), type III (hypoplasia of the lower medial and lateral quadrants, deficiency of skin in the subareolar region) and type IV (severe breast constriction, minimal breast base). Areolar prolapse, usually regarded as a major symptom, was only found in 30 (44%) deformed breasts. Postoperative review of 51 breasts in 31 patients showed that type I cases treated by reduction mammaplasty of adequately sized breasts or augmentation of hypoplastic breasts had excellent results. These procedures with additional spreading of the breast tissue in type II deformities give good results. Severe cases (types III and IV) treated by augmentation and tissue spreading procedures have an unsatisfactory shape and have a 'second crease' deformity. For types III and IV, additional skin in the subareolar region by tissue expansion or flap procedures is necessary. There is no one method to correct 'the' tuberous breast but there are many procedures which should be used according to the type of deformity. The classification developed could end the confusion in nomenclature.

Free transplantation of fat autografts expanded by tissue expanders in rats.

Inguinal fat pads of 28 rats were expanded by tissue expanders for 10 days and transplanted to the back of the same animal. The non-expanded contralateral inguinal fat pads were also transplanted and served as controls. Histology showed that adipocytes lose their lipid droplets under mechanical pressure; the expanded adipocytes have an elongated contour with a central nucleus. By the end of the expansion period, the thickness of the fat pads had decreased by 53%. One week after transplantation, expanded fat grafts had regained their previous volume with little sign of necrosis. Among normal adipocytes numerous smaller cells, containing multiple vacuoles, were seen. In contrast, about 25% of the substance of the non-expanded control fat graft consisted of necrotic oil cysts. These findings indicate that pre-expanded fat grafts survive better.

Enzymatic glucose sensors. Improved long-term performance in vitro and in vivo.

We studied the long-term in vitro and in vivo performance of enzyme electrode glucose sensors. Single commercially produced enzyme-active membranes remained functional for estimating glucose in vitro for 14-36 months. These membranes were implanted subcutaneously in rats for 1 year and, upon explanation, remained functional for measuring glucose in vitro. Sensors with these membranes plus an additional outer membrane with lower glucose permeability allowed glucose monitoring in the low oxygen tension of subcutaneous tissue. These sensors were surgically implanted in three nondiabetic dogs. Each sensor implant was coupled to a radio transmitter to allow continuous long-term glucose monitoring in these awake unrestrained dogs. In vivo sensor performance was evaluated by intravenous glucose infusion, with reference blood glucose determinations made in the clinical laboratory. These subcutaneously implanted sensors tracked changes in plasma glucose for up to 12 weeks. The in vivo initial response for three sensor implants was approximately 35 sec (n = 8). Sensor peak response to glucose after bolus infusion ranged from 3 to 14 min. Stability of sensor sensitivity within +/- 15% for more than 1 month was demonstrated in two of the dogs. Sensor lifetime was limited not by loss of enzyme activity, but by biodegradation of the outermost polyurethane membrane. The findings suggest that long-term continuous monitoring of blood glucose using a subcutaneously implanted enzyme electrode sensor may be possible.

An improved model for rat liver transplantation including arterial reconstruction and simplified microvascular suture techniques.

For experimental liver transplantation in the rat, the models that have been used most frequently do not include reconstruction of the arterial blood supply to the liver. In these procedures, specially developed cuff anastomoses rather than the conventional microvascular suture technique are used almost exclusively in the recipient operation, so that the anhepatic time is minimized. In this study the technical details of an improved rat model for orthotopic liver transplantation are described. During the donor operation in this experimental method, the liver is prepared with an arterial pedicle that includes the abdominal segment of the aorta, permitting perfusion in situ of the portal vein as well as the hepatic artery. The transplantation of the excised donor organ into the recipient site is carried out with simplified microvascular suture techniques and includes reconstruction of the arterial supply to the liver. Anastomosis of the bile duct is accomplished by choledocho-choledochostomy with a splint technique and supplemental suturing. For the entire procedure, magnifying glasses with 2- to 2.5-fold magnification are sufficient. When this technique has been mastered, the average duration of the anhepatic phase is about 20 min, well below the critical 30-min limit for survival of the experimental animals. As proficiency increased, the perioperative mortality was reduced to 9.2% (n = 130). With the combination of portal and arterial in situ flushing during the donor operation and the rearterialization of the transplant during the recipient operation, the clinical conditions can be approximated more closely than is possible when the transplanted rat liver is supplied only by the portal vein. Use of microvascular suture techniques, without cuff anastomoses, reduces the need for ex situ handling of the donor organ.

Simplified microvascular suture techniques for rat liver transplantation as a microsurgical model with arterial blood supply.

The methods for liver transplantation in the rat mainly used do not include reconstruction of the arterial blood supply to the liver. Furthermore, to ensure a short anhepatic phase these methods almost all entail specially developed cuff anastomoses in the recipient operation instead of the conventional microvascular suture technique. Thus an acceptable survival rate can be attained in the experimental animals. This detailed description of simplified microvascular suture techniques is intended to present an alternative to the cuff anastomoses used almost exclusively. In the donor operation with this method, the liver is dissected with an arterial pedicle including the abdominal segment of the aorta, and the liver is flushed in situ not only via the portal vein, but also via the hepatic artery. The organ is implanted in the recipient animal using simplified microvascular suture reconstruction of the arterial blood supply to the liver. Use of telescopic spectacles with 2-fold magnification has proven to be adequate for the entire procedure. With mastery of this method of rat liver transplantation, the average duration of the anhepatic phase is about 20 min, substantially below the 30-min limit which is critical for the survival of the experimental animals. The donor operation requires about 60 min, and the recipient operation 70 to 80 min. With this method, the spectrum of investigations on liver transplantation which are possible in the rat is substantially extended in that clinical conditions can be reproduced very much more exactly by combination of portal and arterial in-situ flushing in the donor operation and rearterialization of the transplant in the recipient operation, as compared to the transplanted rat liver being supplied only with portal venous blood.