[Facial feminization, history, evolution of objectives]. / Féminisation faciale, historique, évolution des objectifs.

The author's experience dates from 1990, during the period when he was in charge of the feminization of the facial skeleton in order to improve the social integration of male transsexual patients. Very quickly, these techniques were extended to genetic women who wanted a more feminine face. This facial skeletal surgery was then supplemented with soft tissue surgery. This skeletal and volumetric surgery has become an important contribution in the search of facial rejuvenation and beauty.

[Benefits of volumetric to facial rejuvenation. Part 1: Fat grafting]. / Apport de la volumétrie au rajeunissement facial. Partie 1 : greffe adipocytaire.

For a number of years, a volumetric approach using autologous fat injection has been implemented to improve cosmetic outcome in face-lift procedures and to achieve lasting rejuvenation. Autologous fat as filling tissue has been used in plastic surgery since the late 19th century, but has only recently been associated to face lift procedures. The interest of the association lies on the one hand in the pathophysiology of facial aging, involving skin sag and loss of volume, and on the other hand in the tissue induction properties of grafted fat, "rejuvenating" the injected area. The strict methodology consisting in harvesting, treating then injecting an autologous fat graft is known as LipoStructure® or lipofilling. We here describe the technique overall, then region by region. It is now well known and seems simple, effective and reproducible, but is nevertheless delicate. For each individual, it is necessary to restore a harmonious face with well-distributed volumes. By associating volumetric to the face lift procedure, the plastic surgeon plays a new role: instead of being a tailor, cutting away excess skin, he or she becomes a sculptor, remodeling the face to restore the harmony of youth.

[Benefits of volumetric to facial rejuvenation. Part 2: Dermal fillers]. / Apport de la volumétrie au rajeunissement facial. Partie 2 : produits de comblement.

Injectable substances known as fillers are used to palliate age-related atrophy and ptosis, and for their so-called "pseudo-lifting" action. They do not replace face and neck lift, but allow it to be postponed or, when injected after surgical lifting, make the result durable. Hyaluronic acid has a predominant and unchallenged place among fillers, well ahead of poly-L-lactic acid or calcium hydroxyapatite. Approaches and injection methods are the same for all fillers, corresponding to those for autologous fat injection, the reference substance, with a few particularities. The substance used, the level of hyaluronic acid reticulation, and the depth of the injection depend on the injection site and intended effect. Effects range from smoothing superficial wrinkles to remodeling whole parts of the face. Complications related to such fillers are well known, especially in the case of hyaluronic acid, where overcorrection is the most frequent. To limit the risk of complications and also to offer each patient the most individually adapted corrections, before any procedure, the plastic surgeon needs to question the patient and perform precise medical examination.

Enhancement of Mixing Performance of Two-Layer Crossing Micromixer through Surrogate-Based Optimization.

Optimum configuration of a micromixer with two-layer crossing microstructure was performed using mixing analysis, surrogate modeling, along with an optimization algorithm. Mixing performance was used to determine the optimum designs at Reynolds number 40. A surrogate modeling method based on a radial basis neural network (RBNN) was used to approximate the value of the objective function. The optimization study was carried out with three design variables; viz., the ratio of the main channel thickness to the pitch length (H/PI), the ratio of the thickness of the diagonal channel to the pitch length (W/PI), and the ratio of the depth of the channel to the pitch length (d/PI). Through a primary parametric study, the design space was constrained. The design points surrounded by the design constraints were chosen using a well-known technique called Latin hypercube sampling (LHS). The optimal design confirmed a 32.0% enhancement of the mixing index as compared to the reference design.

[Lipofilling]. / Comblement par la graisse autologue.

Autologous fat can be considered to be a gold standard implant by virtue of its volumetric qualities and its action on skin trophicity. Improved techniques have transformed fat injections into reproductible adipocyte grafts with permanent results.

Chemical etching of silicon carbide in pure water by using platinum catalyst.

Chemical etching of SiC was found to proceed in pure water with the assistance of a Pt catalyst. A 4H-SiC (0001) wafer was placed and slid on a polishing pad in pure water, on which a thin Pt film was deposited to give a catalytic nature. Etching of the wafer surface was observed to remove protrusions preferentially by interacting with the Pt film more frequently, thus flattening the surface. In the case of an on-axis wafer, a crystallographically ordered surface was obtained with a straight step-and-terrace structure, the height of which corresponds to that of an atomic bilayer of Si and C. The etching rate depended upon the electrochemical potential of Pt. The vicinal surface was observed at the potential at which the Pt surface was bare. The primary etching mechanism was hydrolysis with the assistance of a Pt catalyst. This method can, therefore, be used as an environmentally friendly and sustainable technology.

A treadmill ergometer for three-dimensional ground reaction forces measurement during walking.

This report describes new treadmill ergometer designed to measure the vertical and horizontal ground reaction forces produced by the left and right legs during walking. It was validated by static and dynamic tests. Non-linearity was from 0.2% (left vertical force) to 1.4% (right antero-posterior force). The resonance frequency was from 219 (right vertical direction) to 58 Hz (left medio-lateral direction). A calibration "leg", an air jack in series with a strain gauge, was developed and used to produce force signals comparable to those obtained during human locomotion. The mean differences between the force measured by the calibration leg and treadmill ergometer at 5 km h(-1) were 3.7 N (0.7%) for the left side and 6.5 N (1.2%) for the right. Measurements obtained during human walking showed that the treadmill ergometer has considerable potential for analysing human gait.

Human macrovascular endothelial cells: optimization of culture conditions.

The purpose of this study is to identify optimal culture conditions to support the proliferation of human macrovascular endothelial cells. Two cell lines were employed: human saphenous vein endothelial cells (HSVEC) and human umbilical vein endothelial cells (HUVEC). The influence of basal nutrient media (14 types), fetal bovine serum (FBS), and mitogens (three types) were investigated in relation to cell proliferation. Additionally, a variety of extracellular matrix (ECM) substrate-coated culture dishes were also tested. The most effective nutrient medium in augmenting cell proliferation was MCDB 131. Compared to the more commonly used M199 medium, MCDB 131 resulted in a 2.3-fold increase in cell proliferation. Media containing 20% FBS increased cell proliferation 7.5-fold compared to serum-free media. Among the mitogens tested, heparin (50 microg/ml) and endothelial cell growth supplement (ECGS) (50 microg/ml) significantly improved cell proliferation. Epithelial growth factor (EGF) provided no improvement in cell proliferation. There were no statistical differences in cell proliferation or morphology when endothelial cells were grown on uncoated culture plates compared to plates coated with ECM proteins: fibronectin, laminin, gelatin, or collagen types I and IV. The culture environment yielding maximal HSVEC and HUVEC proliferation is MCDB 131 nutrient medium supplemented with 2 mM glutamine, 20% FBS, 50 microg/ml heparin, and 50 microg/ml ECGS. The ECM substrate-coated culture dishes offer no advantage.

[Pseudospondylodiscitis in chronic hemodialysis. Apropos of 2 cases and review of the literature]. / La pseudospondylodiscite de l'hémodialyse chronique. A propos de deux observations et revue de la littérature.

The spondyloarthropathy of patients on chronic dialysis is a new entity of still obscure pathogenesis. Two cases are reviewed and the documented data analyzed. Radiologic images suggestive of an infectious spondylodiscitis impose performance of a puncture biopsy for bacteriology and histology.

[Imaging of severe forms of hematoma in the rectus abdominis under anticoagulants]. / Imagerie des formes graves de l'hématome des grands-droits sous anticoagulants.

AIM: To describe the US, CT and MRI pattern of the severe rectus sheath hematoma (RSH) complicating anticoagulant therapy. MATERIALS AND METHODS: CT scans were performed in thirteen patients (12 women, 1 man) aged from 53 to 90 (mean age, 74) with severe RSH. Five patients also underwent ultrasound examination and three MR examination. Nine patients (69%) were receiving subcutaneous injection of heparin, three (23%) oral anticoagulant therapy and one continuous IV infusion of heparin. Clinical diagnosis was reached in 6 cases. Excessive activity of anticoagulant therapy was noted in 4 cases. The location of the RSH, their densities and their signal were analysed. RESULTS: All the RSH were mostly developed in the lower third of the abdominal wall, had a large spreading into the Retzius space and compressed the bladder and/or the bowels. RSH were all hyperdense and in 8 cases (61%) a fluid-fluid level due to the hematocrit effect was noted. In one case, a retroperitoneal hematoma was discovered. The extension of the RSH was well delineated with MRI. The RSH showed itself with heterogeneous signal intensities with areas of high-signal-intensity on T1-weighted images. Fluid-fluid levels and a concentric ring sign were also noted. CONCLUSION: Older women with subcutaneous injection of heparin are especially prone to RSH even though there is no overall excessive activity of anticoagulant therapy. Clinical and biological diagnosis may be difficult. CT scan is the exam of choice to reach a precise and acute diagnosis of RSH.

[Contrast-enhanced MRA of the carotid arteries using 0.5 Tesla: comparison with selective digital angiography]. / ARM des bifurcations carotidiennes sur un appareil à 0,5 Tesla: étude comparative à l'angiographie numérisée.

PURPOSE: To assess the feasability, the imaging quality and the effectiveness of contrast-enhanced MRA (CE MRA) using a 0.5 Tesla MR unit in the evaluation of internal carotid artery (ICA) stenosis. Materials and Methods. 29 patients underwent CE MRA and selective digital substraction angiography (DSA). All data were reviewed in a blinded fashion by 2 independant observers. Imaging quality was graded as good, moderate but interpretable, and insufficient. Stenosis was graded according to the NASCET classification from grade 1 to 4, with the following thresholds:<30%,<70%,<99% and occlusion. Inter and intra- observer agreement was evaluated using the kappa index. RESULTS: Imaging quality was good for 79 arteries, moderate for 24 and insufficient for 13 (k MRA=0.72 and 0.64 respectively for the right and left ICAs). Interobserver agreement was good with values for right/left ICA of 0.84/0.94, 0.72/0.74 respectively for CE-MRA and DSA. For the comparison between CE MRA and DSA, agreement was also good, with values of 0.74 and 0.64 for both readers. Sensitivity of CE MRA in the detection of hemodynamically significant stenosis (>70%) was of 0.95 and 0.94 and specifity of 0.91 and 0.89 respectively for reader n degrees 1 and reader n degrees 2. CONCLUSION: CE MRA using a 0.5T MR unit is a valuable technique in the evaluation of ICA stenosis.

[Radiologic aspects of infarction of the appendix epiploica]. / Aspects radiologiques des infarctus d'appendices épiploïques.

Clinical, US, CT and MR findings were reviewed in 5 patients with primary epiploic appendagitis (3 men, 2 women, mean age 38 years, age range 29-62 years) seen between December 1994 and December 1997. Diagnosis was reached in all cases with CT, with US in 3 and with MR in 1. Follow-up CT was performed in 2 cases and clinical follow-up in 4. One patient underwent surgery. Initial US, CT or MR examinations revealed a fatty oval-shaped nodule located anteriorly or anterolaterally to the left colon. The greater diameter ranged from 20 to 30 mm. Perinodular lesions with strands of periappendicular fat and thickened parietal peritoneum were visualized in all cases without any other inflammatory process in the abdomen. Symptoms resolved within 4 days in all patients. Signs of fatty inflammatory processes resolved in the 2 patients who had follow-up CTs. Primary epiploic appendagitis has characteristic US, CT and MR features which help guide medical treatment.

[Gait analysis of 57 healthy children by measurement of ground reaction forces on an Adal treadmill]. / Analyse de la marche de 57 enfants sains par mesure de la réaction au sol sur tapis roulant Adal.

PURPOSE OF THE STUDY: The purpose of this study was to present a new treadmill proposed for evaluating gait in children. We analysed differences in ground reaction forces between boys and girls, and we calculated the symmetry index in healthy children. MATERIAL AND METHOD: Time and ground reaction forces of about 30 steps were measured using a new treadmill. The apparatus consists of 2 walking belts which function as two independent treadmills placed side by side, separated by 4 mm. The 2 treadmills were mechanically separated in order to allow independent measurement of the ground reaction forces induced by each lower limb during stance phase. The children (28 boys and 29 girls), all clinically healthy, were divided into three groups according to their height (between 105 and 150 cm). They walked at three different velocities (2.7 km/h, 3.6 km/h and 4.5 km/h according to their height). The graphs representing the subject's measurements were composed of fore-aft, medial-lateral, and vertical parameters. The analysis of these graphs considered stride, stance, double stance and nine specific points. We also calculated the symmetry index of each child. RESULTS: We determined the values of the symmetry index in healthy children. We did not find any significant difference in gait between girls and boys, except for Fz3 at 2.7 kg/h, where Fz3 was higher in girls than in boys. DISCUSSION: We compared our results with those reported in the literature and found that ADAL has a very important advantage in gait analysis in children because it is simple and easily accepted by children.

[Recurrent laterocervical suppurations. Role of fistulae and cysts of the 4th branchial pouch]. / Suppurations latéro-cervicales récidivantes. Rôle des fistules et kystes de la 4e poche branchiale.

Four cases of fistula of fourth branchial pouch are used as a basis for a description of the two possible clinical pictures: left cervical suppuration in a neonate with respiratory distress or recurrent cervical cellulitis in an older child or young adult usually diagnosed as a suppurative thyroiditis. Diagnostic features are outlined and emphasis placed on the need for an adapted surgical excision originating at the pharyngeal orifice of the fistula. In two of the four cases reported its trajectory was between muscle and mucosa planes and then in contact with the cricothyroid joint as a small cord, otherwise unidentifiable.

[Slowly absorbable and non absorbable injectable products]. / Les produits injectables lentement et non résorbables.

Products which are non absorbable or slowly absorbable make the correction of facial wasting of any origin possible. These highly efficient products are unfortunately sometimes responsible for complications or even undesirable after effects. In order to avoid this the following are necessary: clinical and histological analysis of facias granulomas, a proposal for guidelines for their use which would predict in situ tolerance.

[Role of the septal cartilage in facial growth. Experimental study in rats]. / Rôle du cartilage septal dans la croissance faciale. Etude expérimentale chez le rat.

The authors report a surgical experiment on nasal septal cartilage in the growing rat. Three different operations performed on 95 animals to assess. The role of septal cartilage in facial growth and the effects of standard surgical techniques on facial growth. The results obtained show that sub-periosteal dissection of the nasal bones has no adverse effect on facial growth; conservative procedures such as removal and replacement of septal cartilage, produce minimal effects on facial growth, but large septal cartilage excision obviously impairs facial growth. Guidelines concerning septal surgery in children are suggested in view of these results.

[Retro-maxillary sequellae of craniofacial stenosis. The value of fronto-facial advancement using the Tessier monobloc technic]. / Rétromaxillie séquelle de cranio-facio-sténose. Intérêt de l'avancement fronto-facial par monobloc Tessier.

Monobloc fronto-facial advancement (TESSIER's technic) seems to be the best therapeutic to correct retromaxillia, sequellae of cranio-facio-stenosis. From an aesthetical and functional point of view the result is more satisfactory than with a simple LE FORT III osteotomy advancement. Intermaxillary fixation is not necessary. Of course an orthodontic sequence must be associated to correct dental malposition.