Mathias Tremp

Harvest site influences the growth properties of adipose derived stem cells.

The therapeutic potential of adult stem cells may become a relevant option in clinical care in the future. In hand and plastic surgery, cell therapy might be used to enhance nerve regeneration and help surgeons and clinicians to repair debilitating nerve injuries. Adipose-derived stem cells (ASCs) are found in abundant quantities and can be harvested with a low morbidity. In order to define the optimal fat harvest location and detect any potential differences in ASC proliferation properties, we compared biopsies from different anatomical sites (inguinal, flank, pericardiac, omentum, neck) in Sprague–Dawley rats. ASCs were expanded from each biopsy and a proliferation assay using different mitogenic factors, basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) was performed. Our results show that when compared with the pericardiac region, cells isolated from the inguinal, flank, omental and neck regions grow significantly better in growth medium alone. bFGF significantly enhanced the growth rate of ASCs isolated from all regions except the omentum. PDGF had minimal effect on ASC proliferation rate but increases the growth of ASCs from the neck region. Analysis of all the data suggests that ASCs from the neck region may be the ideal stem cell sources for tissue engineering approaches for the regeneration of nervous tissue.

The regeneration potential after human and autologous stem cell transplantation in a rat sciatic nerve injury model can be monitored by MRI.

Traumatic nerve injuries are a major clinical challenge. Tissue engineering using a combination of nerve conduits and cell-based therapies represents a promising approach to nerve repair. The aim of this study was to examine the regeneration potential of human adipose-derived stem cells (hASCs) after transplantation in a nonautogenous setting and to compare them with autogenous rat ASCs (rASCs) for early peripheral nerve regeneration. Furthermore, the use of MRI to assess the continuous process of nerve regeneration was elaborated. The sciatic nerve injury model in female Sprague-Dawley rats was applied, and a 10-mm gap created by using a fibrin conduit seeded with the following cell types: rASCs, Schwann cell (SC)-like cells from rASC, rat SCs (rSCs), hASCs from the superficial and deep abdominal layer, as well as human stromal vascular fraction (1 × 106 cells). As a negative control group, culture medium only was used. After 2 weeks, nerve regeneration was assessed by immunocytochemistry. Furthermore, MRI was performed after 2 and 4 weeks to monitor nerve regeneration. Autogenous ASCs and SC-like cells led to accelerated peripheral nerve regeneration, whereas the human stem cell groups displayed inferior results. Nevertheless, positive tends could be observed for hASCs from the deep abdominal layer. By using a clinical 3T MRI scanner, we were able to visualize the graft as a small black outline and small hyperintensity indicating the regenerating axon front. Furthermore, a strong correlation was found between the length of the regenerating axon front measured by MRI and the length measured by immunocytochemistry (r = 0.74, p = 0.09). We successfully transplanted and compared human and autologous stem cells for peripheral nerve regeneration in a rat sciatic nerve injury model. Furthermore, we were able to implement the clinical 3T MRI scanner to monitor the efficacy of cellular therapy over time.

Peripheral Nerve Repair: Multimodal Comparison of the Long-Term Regenerative Potential of Adipose Tissue-Derived Cells in a Biodegradable Conduit

Tissue engineering is a popular topic in peripheral nerve repair. Combining a nerve conduit with supporting adipose-derived cells could offer an opportunity to prevent time-consuming Schwann cell culture or the use of an autograft with its donor site morbidity and eventually improve clinical outcome. The aim of this study was to provide a broad overview over promising transplantable cells under equal experimental conditions over a long-term period. A 10-mm gap in the sciatic nerve of female Sprague-Dawley rats (7 groups of 7 animals, 8 weeks old) was bridged through a biodegradable fibrin conduit filled with rat adipose-derived stem cells (rASCs), differentiated rASCs (drASCs), human (h)ASCs from the superficial and deep abdominal layer, human stromal vascular fraction (SVF), or rat Schwann cells, respectively. As a control, we resutured a nerve segment as an autograft. Long-term evaluation was carried out after 12 weeks comprising walking track, morphometric, and MRI analyses. The sciatic functional index was calculated. Cross sections of the nerve, proximal, distal, and in between the two sutures, were analyzed for re-/myelination and axon count. Gastrocnemius muscle weights were compared. MRI proved biodegradation of the conduit. Differentiated rat ASCs performed significantly better than undifferentiated rASCs with less muscle atrophy and superior functional results. Superficial hASCs supported regeneration better than deep hASCs, in line with published in vitro data. The best regeneration potential was achieved by the drASC group when compared with other adipose tissue-derived cells. Considering the ease of procedure from harvesting to transplanting, we conclude that comparison of promising cells for nerve regeneration revealed that particularly differentiated ASCs could be a clinically translatable route toward new methods to enhance peripheral nerve repair.

The Combined Pedicled Anterolateral Thigh and Vastus Lateralis Flap as Filler for Complex Perineal Defects.

AbstractExtensive defects of the pelvis and genitoperineal region are a reconstructive challenge. We discuss a consecutive series of 25 reconstructions with the pedicled anterolateral thigh (ALT) flap including muscle part of the vastus lateralis (VL) in 23 patients from October 1999 to September 2012.Only surface defects larger than 100 cm2 and reconstructions by composite ALT + VL were included in this retrospective analysis. Of the 23 patients, 19 underwent oncologic resection, whereas 4 cases presented Fournier gangrene. Three patients did not reach 6 months of follow-up and were excluded from further data analysis. Among the remaining 20 patients (22 reconstructions), average follow-up period was 14 months (range, 10–18 months). Patient’s average age was 60 years. Average size of the defect was 182 cm2.Postoperative complications included 1 (4.5%) flap necrosis out of 22 raised flaps, 1 partial flap necrosis after venous congestion, and 2 cases where a complementary reconstructive procedure was performed due to remaining defect or partial flap failure. In 6 cases, peripheral wound dehiscence (27%) was treated by debridement followed by split-thickness skin graft or advancement local flaps. Defect size was significantly related to postoperative complications and increased hospital stay, especially in those patients who underwent preoperative radiotherapy. At the end of the follow-up period, a long-term and satisfactory coverage was obtained in all patients without functional deficits.This consecutive series of composite ALT + VL flap shows that, in case of extended defects, the flap provides an excellent and adjustable muscle mass, is reliable with minimal donor-site morbidity, and can even be designed as a sensate flap.

Secret Scar Free Gracilis Flap

The gracilis free flap is a workhorse in plastic surgery. We present a modified technique that relies on a single horizontal thigh-lift-type approach, which (1) gives wide pedicle exposure, (2) provides material for skin grafting, and (3) allows for distal flap transection without an additional incision. Eighteen gracilis free flaps were performed from 2007 to 2009 for lower extremity reconstruction. Complete flap survival was observed in 17 patients with one partial necrosis distally. Our approach allowed access to divide the distal gracilis tendon without a second incision in all cases. The mean scar length was 16 ± 3 cm and no hypertrophic scars were observed. In 15 patients, no visible scar was observed in the upright position, and in three patients, the scar was visible dorsally (2 ± 1 cm). No sensory deficits were observed 6 months postoperatively. In addition, the split-thickness skin graft harvested from the skin paddle was sufficient to cover all defects.

Power-assisted liposuction (PAL) of multiple symmetric lipomatosis (MSL)—a longitudinal study

BACKGROUND Multiple symmetric lipomatosis (MSL) is a rare condition leading to grotesque disfigurement. Complete removal is almost impossible and recurrences inevitable. The objective of this study was to evaluate powered-assisted liposuction (PAL) for the treatment of MSL. METHODS Magnetic resonance imaging (MRI) was performed before and after surgery for quality assessment. To exclude malignancy incisional biopsies were taken before surgery. Outcome measures included aspiration volumes, duration of surgery, early morbidity, recurrence rates, and overall patient satisfaction. RESULTS Seven male patients aged between 43 and 70 years were identified. The mean liposuction volume equaled 2948±1566 mL, the mean surgery time 74±28 minutes. One hematoma was observed, whereas 1 recurrence rate was noticed after a mean follow-up of 14 months. Malignancy was excluded by histology in 5 patients. Preoperative MRI confirmed the diagnosis with no signs for malignancy and showed an efficient removal of the lesions. After a mean follow-up of 18 months, a high patient satisfaction was achieved. CONCLUSION PAL can serve as an efficient method for the treatment of MSL. It has a significant effect on tightening of the skin, leading to a high patient satisfaction.

Three-dimensional laser surface scanning in rhinosurgery

Objective outcome analysis of nasal surgery remains difficult. Recently, evaluation of nasal shape following rhinosurgery shifted from two-dimensional evaluation to more sophisticated three-dimensional (3D) analysis techniques, including stereophotogrammetry, computed tomography, and 3D laser scanning. This article explores the feasibility of using 3D laser surface scanners as a tool for preoperative planning and quality control in rhinosurgery.

The Modified Z-Epicanthoplasty-A Stepwise and Individualized Design.

Purpose To describe a medial epicanthoplasty technique using a stepwise, customized design and to review the outcome in Asian patients after the treatment of medial epicanthal fold. Design Retrospective, noncomparative and interventional case series with the introduction of a new surgical technique. Participants Forty-eight consecutive Asian patients with primary medial epicanthal fold. Methods Patient charts were reviewed from patients (mean age, 24.6 ± 3.8 years; range, 19–40 years) with a stepwise z-epicanthoplasty. The intercanthal distance (ICD), interpupillary distance (IPD), and scar visibility were evaluated at regular intervals (preoperative, immediate postoperative, 3 months, 6 months, and 1 year after the operation). The ratio of the ICD to IPD (ICD ratio) was calculated, and the visibility of the surgical scar assessed. Main Outcome Measures Postoperative improvement in ICD ratio and scar quality. Results The preoperative median ICD ratio was 0.60 (range, 0.57–0.66) and decreased to 0.57 (range, 0.52–0.60) postoperatively. The median ICD ratio reduction was 5.6% (range, 2.6–14.1%; P < 0.001, Wilcoxon signed-rank test). Forty patients (83.3%) had no visible scarring or scarring only visible under close inspection. Eight patients (16.7%) experienced a more apparent scar, but none of them developed a severe scar requiring revision. Conclusions The modified z-epicanthoplasty using a stepwise design is a customized and effective technique for the treatment of the epicanthal fold. This method has a short learning curve, is widely applicable to various types of epicanthal fold, and has a high satisfaction rate with a stable long-term result.

Body Contouring: The Success of the Androgynous Model.

1 Carlo M. Oranges, MD Andreas Gohritz, MD Mathias Tremp, MD Dirk J. Schaefer, MD Department of Plastic, Reconstructive, Aesthetic and Hand Surgery Basel University Hospital Basel, Switzerland Sir: T pharaonic belief in androgynous nature of gods was the motivation for practicing female circumcision in ancient Egypt.1 This historical observation leads us, as plastic surgeons, to consider how much the aesthetical ideals are influenced by philosophical and ethical views. We are called to translate into adequate treatments for our patients the concept of beauty, which evolves along the history and is strictly related to the spirit of every period. Interestingly, several studies during the last decades reported a reemerging trend toward the androgynous model. An androgyny index, based on waist, bust, and pelvic width, was introduced in 2002 to investigate female body attractiveness.2 Analyzing temporal changes, a trend toward the success of a more androgynous appearance was observed in photograph models’ body shapes over the period of 50 years until 2001. The androgyny index was further validated by studies published in Plastic and Reconstructive Surgery.3 Moreover, this evolution of aesthetical ideals was reflected by the increased preoccupation for specific parts of the body, leading to an increase in requests for related body contouring operations.4 After the Egyptians, the idea of the androgynous nature of the primordial human being was philosophically developed by Plato in Symposium 189a– 193e through the speech of Aristophanes. By using a mythical narration, Plato said that in the beginning, the androgynous human being was participating in both male and female natures. Afterwards, Zeus, the king of gods in Greek Olympus, divided the androgyne in man and woman to reduce the extraordinary power related to the androgynous nature. However, as a consequence, one of the strongest desires was generated in the human being: the research of the lost unity through Love. These philosophical beliefs oriented the aesthetical ideals of the Hellenistic period and were expressed in art by many sculptures representing Aphroditus. During the Italian Renaissance period, these ideas were rediscovered by the Neo-Platonic Academy of Marsilio Ficino, which adopted a monistic interpretation of the Nature and proposed that an ultimate One lies behind all existence.5 Conversely, dualism between thought and reality had to be overcome.5 Classical symbolic expressions of dualism, like the opposites above/below, in/out, and in biology male/female, man/woman, were judged as mere appearance. The androgynous model represented the ideal reconciliation of the human being with the original Unity mentioned above. Steeped in this Neo-Platonic view, Renaissance art was guided by philosophy.5 Leonardo da Vinci’s drawing Androgynous is probably the most explicit representation of the androgynous model in this period. Androgynous characters can also be identified in the Leonardo’s most famous painting, Mona Lisa, and in St. John the Baptist. After Napoleon Bonaparte’s campaign in Egypt and Syria (1798–1801), the Egyptian philosophy and aesthetical principles were widely rediscovered and accepted with increasing interest in the Western countries. In 20th century, Jung postulated that both masculine and feminine components of the psyche are present in each individual.6 Accordingly, androgyny was considered as expression of the unified self. Today, the androgynous tendency can be easily recognized as a part of the pop culture, reflecting the success of the philosophical background described above. To be aware of this view of human nature may help us to better understand the aesthetical ideals of our period and, consequently, the requirements of our patients.

A simple, reliable, and inexpensive intraoperative external expansion system for enhanced autologous structural fat grafting

External volume expansion of the recipient site by suction has been proposed as a way of improving fat graft survival. The objective of this study was to present an innovative and simple intraoperative external expansion system to enhance small-volume autologous fat grafting (40–80 mL) and to discuss its background and its mechanism of action. In this system, expansion is performed using a complete vacuum delivery system known as the Kiwi VAC-6000M with a PalmPump (Clinical Innovations). The recipient site is rapidly expanded intraoperatively 10 times for 30 seconds each with a negative pressure of up to 550 mm Hg before autologous fat injection. During this repetitive stimulation, the tissues become grossly expanded, developing macroscopic swelling that regresses slowly over the course of hours following the cessation of the stimulus. The system sets various mechanisms in motion, including scar release, mechanical stimulation, edema, ischemia, and inflammation, which provide an environment conducive for cell proliferation and angiogenesis. In order to maintain the graft construct in its expansive state, all patients are encouraged postoperatively to use the Kiwi three times daily for one minute per session over the course of three days. The handling of this system is simple for both the patients and the surgeon. Satisfactory clinical outcomes have been achieved without significant complications.