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Reduced quasilinear and nonlinear (gradient-driven) models with scale separations, commonly used to interpret experiments and to forecast turbulent transport levels in magnetised plasmas, are tested against nonlinear models without scale separations (flux-driven). Two distinct regimes of turbulence—either above threshold or near marginal stability—are investigated with Boltzmann electrons. The success of reduced models hinges in particular on the reproduction of nonlinear fluxes. Good agreement between models is found above threshold, whilst reduced models significantly underpredict fluxes near marginality, overlooking mesoscale flow organisation and turbulence self-advection. Constructive prescriptions whereby to improve reduced models are discussed.

ZusammenfassungDie Perforansvenen (PV) der unteren Extremitäten sind nicht nur gerade und direkte Verbindungen zwischen den tiefen und oberflächlichen Venennetzen, sondern bilden gemeinsam ein weit verzweigtes Netz. Trotz ihrer starken anatomischen Variabilität ist ihre Position bemerkenswert konstant und prognostizierbar. Dies ist durch ihre enge Beziehung zu den Muskelvenen bedingt und durch die hämodynamischen Ebenen entlang der Extremität zu erklären. Sie sind bei der Beurteilung durch Ultraschalluntersucher in der täglichen Praxis eine Hilfe.Der anatomische Inhalt dieses Artikels stammt aus folgenden Quellen: Anatomische Präparationen von C. Gillot nach Latex-Injektion und anschließender farblicher Unterteilung von über 400 Extremitäten. Dreidimensionale Rekonstruktionen von CT-Venografien von 1200 Extremitäten und präoperativen Hautvenenvermessungen von 25 000 Extremitäten.Es wird Folgendes beschrieben: Referenzpunkte der Extremität, Perforansvenen des Fußes, Beins und Sprunggelenks, der Wade, Anastomosen zwischen den Perforansvenen, Begleitarterien der Bein-PVs und Oberschenkel-PVs.

International audience; A model of E×B staircases is proposed, based on a wave kinetic equation coupled to a poloidal momentum equation. A staircase pattern is idealised as a periodic radial structure of zonal shear layers that bound regions of propagating wave packets, viewed as avalanches. Wave packets are trapped in shear flow layers due to refraction. In this model an E × B staircase motif emerges due to the interaction between propagating wave packets (avalanches) and trapped waves in presence of an instability drive. Amplitude, shape, and spatial period of the staircase E × B flow are predicted as functions of the background fluctuation spectrum and the growth rate of drift waves. The zonal flow velocity radial profile is found to peak near its maxima and to flatten near its minima. The optimum configuration for staircase formation is a growth rate that is maximum at zero radial wave number. A mean shear flow is responsible for a preferential propagation speed of avalanches. It is not a mandatory condition for the existence of staircase solutions, but has an impact on their spatial period.

The interplay between toroidal drift-wave turbulence and tokamak profiles is investigated using a wave-kinetic description. The coupled system is used to investigate the interplay between marginally stable toroidal drift-wave turbulence and geodesic acoustic modes (GAMs). The coupled system is found to be unstable. Notably, the most unstable mode corresponds to the resonance between the turbulent wave radial group velocity and the GAM phase velocity. For a low-field-side ballooned drift-wave growth, a background flow shear breaks the symmetry between inwards- and outwards-travelling instabilities. Although this turbulence–GAM coupling may not be the primary driver for avalanches in standard core ion temperature gradient simulations, this mechanism is generic and displays many of the expected features, and should be of interest in several other regimes, which include towards the edge or in the presence of energetic particles.

This paper presents a model for zonal flow generation based on a wave kinetic equation coupled to a poloidal momentum equation in a regime where wave trapping matters. Several models of the wave collision operator have been tested: Krook, diffusion and diffusion plus an instability growth rate. Conditions for zonal instability have been identified. It is found that a zonal instability is possible in all cases. However the force is a power law of the zonal velocity, so different from the quasi-linear case of random phases that produces a force that is linear in velocity. Also the zonal force may change sign, leading to flow radial profiles that are not sinusoidal.

Introduction Le syndrome de Wolfram est une maladie neurodegenerative rare, autosomique recessive. Il associe un diabete insulinodependant des l’enfance et une atrophie optique bilaterale. Le diabete insipide et la surdite de perception completent la tetrade connue sous le nom du syndrome de DIDMOAD (Diabetes Insipidus, Diabetes Mellitus,Optic Atrophy and Deafness). Observation Patiente de 53 ans, vue a l’âge de 41 ans avec un diabete etiquete de type 1 diagnostique a l’âge de 17 ans avec une atrophie optique connue depuis l’âge de 19 ans. Association a une neuropathie peripherique, deficience sensorielle avec agueusie et anosmie, syndrome vestibulaire et dystonie vegetative: hypotension orthostatique, tachycardie, probable gastroparesie et vessie neurologique documentee. Presence de troubles cognitifs et syndrome depressif. Devant ce tableau atypique comportant un diabete insulinotraite et atrophie optique, le syndrome de Wolfram est evoque. L’etude genetique a la recherche de mutation du gene WFS1 revient positive. Le tableau clinique est domine par l’atteinte neurologique ayant cause la perte d’autonomie et l’atteinte vesicale cause d’infections urinaires recidivantes. Une prise en charge multi-disciplinaire a ete instauree. Discussion L’association diabete et atrophie optique doit faire evoquer le syndrome de Wolfram independamment de la tetrade classique retrouvee dans 53 % des cas. Le diabete represente la premiere manifestation. Les manifestations urinaires sont frequentes (environ 90 % des patients). Le diagnostic precoce permet une prise en charge globale multidisciplinaire pour une meilleure insertion sociale et un depistage systematique des autres atteintes neurosensorielles pouvant engendrer un handicap et urologiques susceptibles d’impacter le pronostic vital des patients.

Introduction: Our objective is to highlight the role of the semi-membranosus muscle, which is surprisingly not described in the major books of anatomy, as main thigh pump in the venous return [1]. Material and methods: Latex injection of fresh cadavers followed by anatomical dissection and colored segmentation of the whole venous network of 300 lower limbs, 3D reconstructions by CT venography of 1000 CVD patients are at the basis of this study. Results: The venous arcades of the semi-membranosus muscle constitute a main deep collateral route by-passing the narrowed area of the Hunter’s canal. This anatomical study clearly shows that these venous arcades are regularly connected:(Figure 1) • By their 2 lower branches to the popliteal vein • By their 2 higher branches to the deep femoral vein. Consequently, they constitute a derivative route of the femoral axis, explaining their dilatation in case of stenosis of the Hunter’s canal outlet. Similarly, in a physiological situation, the whole amount of blood ejected by the powerful calf pump through the popliteal vein cannot always reach the femoral vein through the Hunter’s canal: the arcades then play the role of a safety valve. Moreover, the veins of the semi-membranosus muscle constitute a main thigh pump: they push up the blood towards the femoral crossroad at the root of the limb. Discussion and conclusion: The veins of the semi-membranosus should be systematically investigated by USD : their dilatation is the witness of venous outlet syndrome of the Hunter’s canal which is a major cause of femoral vein thrombosis. USD investigation should be systematically carried out at that levels to prevent future deep vein obstruction.

Introduction: The aim of this study is to make an anatomical description of the bony venous perforators (PVs) at the knee level witch are frequently missed during investigation of patients with chronic venous disease. Material and methods: Multiple series of anatomical slices of fresh cadavers injected with green latex and series of CT venographies as well as Duplex color investigations were used to study their precise location and the connections with the venous network of the knee. Results: Anatomically, these PVs are commonly located anteriorly around the patella, and posteriorly in the inter-condylar grove, medially and laterally. Their connections with the popliteal vein are multiple. During Duplex ultrasound assessment, as well as CT venography, they are often ignored due to their small caliber. Discussion and conclusions: Physiological hypothesis: At the knee level, The spongy bone of both tibia and femur epiphysis is an important place of production of red blood cells. They connect the venous system in the popliteal vein by several tiny perforators. In practice, these tiny perforators are not investigated and ignored by the sonographers. They should be distinguished from the big PVs of the tibial diaphysis responsible for varicose veins of the leg [1]. These PVs could also be linked to the so-called “phleboarthrosis” described recently [2]. The bony perforator veins of the knee are commonly responsible for reticular veins or telangiectases around the knee, but they are underdiagnosed by the sonographers. This explains why the injection of these cosmetic lesions around the knee frequently leads to recurrence.

Introduction: “Adductor canal syndrome”, or “Jogger’s syndrome” has been described as an unusual cause of acute arterial occlusion in younger men. It is also been identified as a cause of compressive neuropathy of the saphenous nerve. Nevertheless, femoral vein compression in the canal has never been described. Our aim is to describe the anatomy and physiology of Hunter’s canal, and to show that the femoral vein is much more exposed than the artery to compression inside the adductor hiatus, particularly at the outlet [1]. Material and methods: Fifty fresh cadavers were used to surgically expose the adductor hiatus for anatomical study. A series of 200 phlebographies and 100 CT venographies were also used to study the 3D morphology of the adductor hiatus. Results: Anatomically, in all cases we found that an abnormal musculotendinous band arose from the adductor magnus muscle, and joined the adductor tendon to the vastus medialis. The femoral vein is located more posteriorly and is frequently narrowed at this level : the edge of the vasto-adductor membrane. This was particularly true when the artery was calcified. Different types of anatomical compression of the femoral vein could by described, but the main is in the Hunter’s outlet: the edge of the vasto-adductor membrane. The resultant anatomical structure creates a notch with venous stenosis frequently occurring at the lower part of the hiatus, well seen in the cast of a femoral vein injected with latex and on the phlebographies In a majority of cases where such a stenosis was found, it was at the lower part of the canal, 13 to 15 cm above the femoral condyle. Compression by the artery or higher inside the canal could also be identified, but they are often ignored. Discussion and conclusion: Physiological hypothesis: The cadaveric simulations showed that contraction of the adductor longus closes the hiatus, and the adductor magnus opens it. Our hypothesis is that Hunter’s canal prevents femoro-popliteal axis reflux by synchronizing with calf pump ejection during ambulation. So in clinical practice, USD investigation should be a routine, seeking for a dilatation of the derivative routes, particularly the arcades of the semi-membranosus muscle: Compression of the femoral vein in the adductor canal is an underestimated cause of venous obstruction and deep vein thrombosis. Ultrasound investigation of both limbs should systematically be carried out at this precise level to prevent future venous obstruction from occurring here.

Barely trapped and passing electrons have been recently predicted to strongly enhance the damping rate of Geodesic Acoustic Modes (GAMs) in tokamak plasmas, while keeping their real frequency almost unchanged as compared to the case with adiabatic electrons. In this paper, dedicated gyrokinetic simulations are successfully compared with these analytical predictions. Specifically, the scaling of the GAM damping rate with respect to the ion to electron mass ratio, to the electron to ion temperature ratio, to the safety factor, and to the aspect ratio is recovered in most regions of the relevant parameter space.

The embryogenesis of the venous network of the lower limbs explains the main variations of the venous network superficial veins, perforating veins, and deep venous system. It is likely that the number of the so-called primitive chronic venous disease could be explained by unknown underlying anatomical abnormalities [1].

International audience; Trace impurity transport is studied with the flux-driven gyrokinetic GYSELA code [V. Grandgirard et al., $Comp.\ Phys.\ Commun.$\ 207, 35 (2016)]. A reduced and linearized multi-species collision operator has been recently implemented, so that both neoclassical and turbulent transport channels can be treated self-consistently on an equal footing. In the Pfirsch-Schlüter regime likely relevant for tungsten, the standard expression of the neoclassical impurity flux is shown to be recovered from gyrokinetics with the employed collision operator. Purely neoclassical simulations of deuterium plasma with trace impurities of helium, carbon and tungsten lead to impurity diffusion coefficients, inward pinch velocities due to density peaking, and thermo-diffusion terms which quantitatively agree with neoclassical predictions and NEO simulations [E. Belli et al., $Plasma\ Phys.\ Control.\ Fusion$ 54, 015015 (2012)]. The thermal screening factor appears to be less than predicted analytically in the Pfirsch-Schlüter regime, which can be detrimental to fusion performance. Finally, self-consistent nonlinear simulations have revealed that the tungsten impurity flux is not the sum of turbulent and neoclassical fluxes computed separately, as usually assumed. The synergy mostly results from the turbulence-driven in-out poloidal asymmetry of tungsten density. This result puts forward the need for self-consistent simulations of impurity transport, i.e. including both turbulence and neoclassical physics, in view of quantitative predictions for ITER.

Type 1 diabetes (T1D) is due to the loss of both beta-cell insulin secretion and glucose sensing, leading to glucose variability and a lack of predictability, a daily issue for patients. Guidelines for the treatment of T1D have become stricter as results from the Diabetes Control and Complications Trial (DCCT) demonstrated the close relationship between microangiopathy and HbA1c levels. In this regard, glucometers, ambulatory continuous glucose monitoring, and subcutaneous and intraperitoneal pumps have been major developments in the management of glucose imbalance. Besides this technological approach, islet transplantation (IT) has emerged as an acceptable safe procedure with results that continue to improve. Research in the last decade of the 20th century focused on the feasibility of islet isolation and transplantation and, since 2000, the success and reproducibility of the Edmonton protocol have been proven, and the mid-term (5-year) benefit-risk ratio evaluated. Currently, a 5-year 50% rate of insulin independence can be expected, with stabilization of microangiopathy and macroangiopathy, but the possible side-effects of immunosuppressants, limited availability of islets and still limited duration of insulin independence restrict the procedure to cases of brittle diabetes in patients who are not overweight or have no associated insulin resistance. However, various prognostic factors have been identified that may extend islet graft survival and reduce the number of islet injections required; these include graft quality, autoimmunity, immunosuppressant regimen and non-specific inflammatory reactions. Finally, alternative injection sites and unlimited sources of islets are likely to make IT a routine procedure in the future.

Objectif Decrire la disposition anatomique des veines perforantes (VPs) du genou qui sont le plus souvent negligees ou ignorees lors des explorations des patients atteints de maladie veineuse chronique (MVC). Materiel et methodes De nombreuses series de coupes anatomiques realisees apres injection de latex sur des cadavres frais, des explorations par phlebo-scanner et duplex couleur ont ete utilisees pour etudier leur repartition et leur connexion avec le reseau veineux du genou. Resultats Anatomiquement, ces VPs sont principalement situees en avant, autour de la patella, et en arriere dans l’echancrure inter condylienne de part et d’autre de la veine poplitee avec laquelle elles ont des connexions multiples. Leur petit calibre explique qu’elles soient souvent meconnues lors de l’exploration par Duplex couleur ou par phlebo-scanner. Discussion Explication physiologique au niveau du genou, l’os spongieux situe dans les 2 epiphyses du tibia et du femur est un important lieu de production des globules rouges (plus important que le rachis). Ces globules doivent donc regagner le systeme veineux vers la veine poplitee par des communication trans-osseuses. Ceci explique la presence de ces multiples petites perforantes gonales. En pratique, leur petit calibre et leur situation expliquent qu’elles passent souvent inapercues lors d’une exploration sonographique du reseau veineux. Diagnostic differentiel: il faut bien les distinguer des grosses perforantes osseuses de la diaphyse tibiale, assez rares et responsables de varices anterieures de jambe rapportees par A.A Ramelet [1] . Enfin, ces VPs jouent probablement un role dans la “phlebarthrose” decrite recemment dans les insuffisances veineuses d’origine variqueuse par plusieurs auteurs [2] . Conclusion Les perforantes osseuses du genou sont tres souvent impliquees dans les recidives apres traitement des veines reticulaires ou des telangiectasies du genou. Leur connexion etroite avec le reseau genicule en est une explication plausible.

Objective To study the anatomy of the veno-muscular pumps of the lower limb, particularly the calf pump, the most powerful of the lower limb, and to confirm its crucial importance in venous return. Methods In all, 400 cadaveric limbs were injected with green Neoprene latex followed by an anatomical dissection. Results The foot pump is the starter of the venous return. The calf pump can be divided into two anatomical parts: the leg pump located in the veins of the soleus muscle and the popliteal pump ending in the popliteal vein with the unique above-knee collector of the medial gastrocnemial veins. At the leg level, the lateral veins of the soleus are the bigger ones. They drain vertically into the fibular veins. The medial veins of the soleus, smaller, join the posterior tibial veins horizontally. At the popliteal level, medial gastrocnemial veins are the largest veins, which end uniquely as a large collector into the popliteal vein above the knee joint. This explains the power of the gastrocnemial pump: during walking, the high speed of the blood ejection during each muscular systole acts like a nozzle creating a powerful jet into the popliteal vein. This also explains the aspiration (Venturi) effect on the deep veins below. Finally, the thigh pump of the semimembranosus muscles pushes the blood of the deep femoral vein together with the quadriceps veins into the common femoral vein. Conclusion The veno-muscular pumps of the lower limb create a chain of events by their successive activation during walking. They play the role of a peripheral heart, which combined with venous valves serve to avoid gravitational reflux during muscular diastole. A stiffness of the ankle or/and the dispersion of the collectors inside the gastrocnemius could impair this powerful pump and so worsen venous return, causing development of severe chronic venous insufficiency.

The aim of this paper is to describe the anatomical relations of the small saphenous vein (SSV) in order to define the high-risk zones for the treatment of chronic venous disease. The SSV runs in the saphenous compartment demarcated by two fascia layers: a muscular fascia and a membranous layer of subcutaneous tissue. The clinician should be keenly aware of the anatomical pitfalls related to the close proximity of nerves to the SSV in order to avoid their injury: At the ankle, the origin of the SSV is often plexiform, located deep below the fascia, and the nerve is really stuck to the vein. The apex of the calf is an area of high risk due to the confluence of nerves which perforate the aponeurosis. Moreover, the possible existence of a ‘short saphenous artery’ which poses a high risk for injection of a sclerosing agent due to a highly variable disposition of this artery surrounding the SSV trunk. For this reason, procedures under echo guidance in this area are mandatory. The popliteal fossa is probably a higher risk zone due to the vicinity of the nerves: the small saphenous arch is close to the tibial nerve, or sometimes the nerve of the medial head of the gastrocnemius muscle. In conclusion, before foam injection or surgery, a triple mapping of the small saphenous territory is mandatory: venous haemodynamical mapping verifying the anatomy that is highly variable, nerve mapping to avoid trauma of the nerves and arterial mapping. This anatomical study will help to define the main high-risk zones.

High efficiencies have been demonstrated on n-type solar cells thanks to advanced passivation layers and metallisation techniques. In this paper we present the latest results obtained with our bifacial cell structure, using BCl3 diffusion for emitter formation, thermal SiO2 passivation and screen-printing metallisation. By continuously improving front side contact quality and reducing substrate bulk lifetime degradation we were able to steadily increase the efficiency of our solar cells from 18.8% to 19.8% on large area c-Si wafers. A first PV module of 21 cells exhibiting an output power of 92 Wp was fabricated.

International audience; The staircase transport regime reported in kinetic simulations of plasma turbulent transport in magnetic confinement is recovered with a simple 2D fluid model allowing for reduced damping of the zonal flows. Some of the complex dynamics of the kinetic zonation regime are recovered but the pattern of the corrugation appears to be sinusoidal with a characteristic scale comparable to that of turbulence modes with largest spectral energy, in contrast to regimes observed in global and flux-driven kinetic simulations. Enhanced zonal flows govern both an overall reduction of the SOL width and a gradual steepening of the gradients with distance to the separatrix.

Introduction L’hyperparathyroidie primaire est souvent infra clinique, parfois symptomatique et alors revelee par une complication de type fracture, lithiase urinaire ou hypercalcemie aigue. Nous rapportons le cas d’une patiente dont l’hyperparathyroidie s’est revelee par un hematome cervical anterieur. Observation La patiente, âgee de 67 ans ayant pour seul antecedent une colectomie partielle pour pathologie benigne a presente un malaise qui amene a la prescription d’un anti-aggregant plaquettaire. Deux mois plus tard, elle presente une douleur avec dysphagie et ecchymose cervicale anterieure. Le scanner et l’echographie montrent une image retrothyroidienne gauche avec deviation tracheale vers la droite, sans compression. Le bilan phosphocalcique initial etait normal. Un mois plus tard, il montre un tableau d’hyperparathyroidie primaire avec calcemie corrigee a 107 mg/L (85–105), phosphoremie a 24 mg/L (25–45), PTH 185 pg/mL (10–65), 25OH vit D 23 ng/mL (> 30). L’echographie cervicale confirme un aspect d’hypertrophie parathyroidienne inferieure gauche, confirme en scintigraphie au MIBI-Tc. Le bilan de retentissement montrant des lithiases urinaires, une chirurgie est decidee. La patiente a eu une cervicotomie laterale gauche montrant un nodule semblant d’origine parathyroidienne, confirmee par l’examen anatomopathologique. Le caractere adenomateux ou hyperplasique n’etait pas precisable compte tenu des sequelles de l’hemorragie. En post-operatoire, la calcemie est corrigee a 99 mg/L, phosphoremie 28 mg/L. Le bilan reste stable avec un recul de 10 mois maintenant. Discussion L’hemorragie d’un adenome parathyroidien est une complication exceptionnelle mais deja decrite, elle peut reveler ou guerir l’adenome, un peu comme l’apoplexie d’un adenome hypophysaire.

Introduction La maladie de Basedow est une cause frequente d’hyperthyroidie, de tableau souvent typique et traitement bien codifie. Nous rapportons le cas d’une patiente, dont le diagnostic, l’evolution, la prise en charge ont ete difficiles. Observation La patiente, âgee de 68 ans presente un coma febrile avec fibrillation auriculaire, hyperthermie, par crise aigue thyrotoxique justifiant une prise en charge initiale en reanimation, et traitee par betabloquants, cholestyramine et propylthio-uracile (PTU). Il existait un goitre multinodulaire volumineux (110 mL), hypervasculaire avec TBII a 116 UI/L. L’hyperthyroidie initialement majeure s’est normalisee en quelques mois sous PTU (8 cp/j) ensuite associe au levothyrox poursuivis 2 ans a forte dose en raison de la normalisation tardive de la vascularisation thyroidienne et des TBII, puis une diminution progressive etait initiee pour preparer une thyroidectomie. En cours de decroissance, le PTU est arrete apres 3 ans de traitement devant une anemie puis une insuffisance renale, en rapport avec une vascularite a ANCA a un titre de 1/1280 de type anti-MPO, confirmee par une biopsie renale. Celle-ci est traitee par corticotherapie et immunosuppresseurs (cyclophosphamide) avec une amelioration partielle de la fonction renale. A distance de l’immunosuppression majeure, une thyroidectomie est realisee sans complication. Discussion La maladie de Basedow peut avoir une presentation grave. Ici, la crise thyrotoxique avait fait preferer le PTU, probablement responsable de la vascularite a ANCA. Malgre les facteurs pejoratifs (goitre volumineux, hypervascularisation, TBII tres eleves), la chirurgie a pu debarrasser la patiente de sa maladie thyroidienne, mais l’insuffisance renale persiste.

Introduction Le goitre rapidement evolutif et compressif peut etre difficile a prendre en charge. Nous rapportons le cas d’une patiente presentant un goitre atypique qui avait fait evoquer un lymphome thyroidien. Observation La patiente, âgee de 68 ans etait adressee en consultation specialisee pour goitre compressif evolutif en 3 mois, avec dyspnee, voix rauque. Ce goitre etait globuleux, dur, avec signes compressifs (cornage, manœuvre de Pemberton, dyspnee), associe a une thyroidite franche (ATPO > 8000 UI/L, N En echographie, il etait extremement hypoechogene et heterogene, globuleux, sans nodule franc, predominant a droite, sans adenopathie, volumineux (130 mL). On notait par ailleurs une calcitonine negative, β2 μglobuline 2,9 mg/L ( Malgre la normalisation de la TSH sous levothyrox, ni le volume du goitre ni les signes compressifs n’etaient modifies, justifiant une thyroidectomie apres corticotherapie. Les suites ont ete simples et l’anatomopathologie a confirme une « simple » thyroidite lymphocytaire. Discussion Ce cas illustre la potentielle severite clinique des thyroidites d’Hashimoto qui peuvent amener a une indication de thyroidectomie quand elles sont d’evolution rapide, compressives, ou en cas de doute concernant un lymphome (80 % de thyroidite associee), entite rare heterogene, pour laquelle on connait le faible apport de la cytoponction.

BackgroundThe venous anatomy is highly variable. This is due to possible venous malformations (minor truncular forms) occurring during the late development of the embryo that produce several anatomical variations in the number and caliber of the main venous femoral trunks at the thigh level. Our aim was to study the prevalence of the different anatomical variations of the femoral vein at the thigh level.MethodsThis study used 336 limbs of 118 fresh, nonembalmed cadavers. The technique included washing of the whole venous system, latex injection, anatomical dissection, and then painting of the veins.ResultsThe modal anatomy of the femoral vein was found in 308 of 336 limbs (88%). Truncular malformations were found in 28 of 336 limbs (12%); unitruncular configurations in 3% (axo femoral trunk [1%] and deep femoral trunk [2%]). Bitruncular configurations were found in 9% (bifidity of the femoral vein [2%], femoral vein with axio-femoral trunk [5%], and femoral vein with deep femoral trunk [2%]).ConclusionTruncular venous malformations of the femoral vein are not rare (12%). Their knowledge is important for the investigation of the venous network, particularly the venous mapping of patients with cardiovascular disease. It is also important to recognize a bitruncular configuration to avoid potential errors for the diagnosis of deep venous thrombosis of the femoral vein, in the case of an occluded duplicated trunk.Clinical RelevanceTruncular venous malformations of the femoral vein are not rare. For the investigator, it may be clinically prudent to scan the opposite limb in the presence of venous duplication since femoral vein duplication is frequently bilateral. It should also be noted that a thrombus is more likely to be seen in one canal of a duplicated femoral vein than in the normal anatomy. Thus, a thrombus in that canal could be easily missed on ultrasound. For the surgeon, femoral vein duplication could provide the opportunity to use one of the trunks for deep vein transposition reconstruction surgery of the opposite limb.

Objectif Contrairement a la fameuse pompe du mollet, les pompes musculaires de cuisse sont mal connues et jouent un role important dans le retour veineux du membre inferieur. Materiel et methodes L’injection du systeme veineux de cadavres frais au Lalex suivie de la dissection anatomique de 300 membres inferieurs, des reconstructions 3D par scanner helicoidal apres injection du systeme veineux de 400 patients insuffisants veineux, ont ete utilisees pour cette etude. Resultat Les arcades veineuses du muscle semi-membraneux constituent un important reseau veineux profond anastomotique de cuisse qui shunte le canal de Hunter. En effet, elles sont connectees a leur pole inferieur a la veine poplitee haute par 2 branches et a leur pole superieur a la veine profonde de cuisse par 2 ou 3 branches. Ces veines musculaires peuvent se dilater en cas de surcharge de la veine poplitee par reflux ou par obstacle du defile du canal de Hunter, conduit fibreux et inextensible qui comprime souvent la veine poplitee haute. De plus, elles constituent une pompe sus-poplitee efficace pour ramener le sang a la racine du membre vers le carrefour femoral dans la phase du pas (…) ou le canal femoral est ferme. Leur dilatation est facile a mettre en evidence par une exploration au Duplex couleur, en placant la sonde Doppler un peu en dedans de la ligne mediane, 10 cm au-dessus du pli poplite. Conclusion Les arcades veineuses du muscle semi-membraneux meritent d’etre explorees systematiquement lors du bilan echo-Doppler des patients veineux, car leur dilatation peut temoigner d’un obstacle sus-poplite au niveau du canal de Hunter. Celui-ci est bien souvent meconnu et pourtant frequemment responsable d’une recidive apres chirurgie de la petite saphene.

Objectives: The purpose of this study is to better understand the anatomy of the venous network of the lower limbs by using new imaging techniques, particularly the three-dimensional modelling by computerized tomographic (CT) venography. This new tool is combined with anatomical dissection techniques and the results of Duplex ultrasound imaging. Methods: The embryogenesis of the venous network, which explains the main variations of the venous system, and a description using the new terminology of the veins. Results: Physiologically, the muscular veins play a crucial role, owing to the effect of the muscular pumps by their aspiration power on the superficial system via the perforators. They always act at the same level. This explains the fixity of the main perforator veins and the interest of their anatomical knowledge. Conclusion: The new imaging techniques and treatments dedicated to the venous system of the lower limbs make their descriptive anatomy increasingly useful. It will be the basis of a common language between radiologists, phlebologists and surgeons.

Plasma processing of porous organo-silicate Iowie dielectrics, following the damascene approach. remains one the biggest challenge for IC manufacturing. During low-k plasma etching. reactive radicals (O∗, F∗ amongst others) and VUV penetrate easily into the porous low-k structure, reacting with Si-CH 3 terminating bonds, ultimately turning the etched low-k hydrophilic and raising the integrated k-value beyond acceptable limits.

Objectif Les PVVI forment un large reseau veineux continu, avalvule intrarachidien allant du sacrum jusqu’a l’endocrâne. Notre but est de demontrer leur role majeur comme voie de derivation en cas d’obstruction ilio-cave. Materiel et methodes Des reconstructions 3D par scanner helicoidal ou IRM apres injection du systeme veineux de 30 cadavres au latex ou a l’altufix associees a un produit de contraste, suivies de corrosion a l’acide sont a la base de cette etude. Cent cinquante phlebographies sous occlusion cave realisees en pratique clinique ont ete egalement utilisees. Resultat Ces plexus veineux constituent un immense reseau anastomotique avalvule du crâne au sacrum, communiquant a chaque etage metamerique par les foramen avec les plexus veineux extrarachidiens constitues par les systemes veineux azygos et lombaire. A l’etage pelvien, les PVVI se resument a 2 lames ventrales plaquees contre le corps de S1 et S2. Elles s’ouvrent dans la veine iliaque interne dont elle constitue la principale voie de derivation parietale. A noter que les veines des trous de conjugaison S1 et L5 engainent veritablement les branches anterieures des nerfs L5 et S1. Ceci explique la sciatalgie au cours des thromboses iliaques diffuses. A l’etage lombaire, les PVVI ventraux sont les plus developpes car ils recoivent les veines basi-vertebrales. Ils sont volumineux, avec aspect en ailes de papillon et se drainent de chaque cote dans une voie longitudinale intrarachidienne continue. Sur celles-ci naissent les veines des trous de conjugaison qui sont connectees aux plexus extrarachidiens inclus dans l’epaisseur du psoas. Celles-ci se drainent selon 2 grands courants longitudinaux : l’un descendant, la veine ilio-lombaire, l’autre ascendant, la racine laterale de l’azygos. Du cote droit, elle nait typiquement de la veine lombaire en L2. Du cote gauche, elle nait directement de la veine renale par le classique arc reno-azygo-lombaire de Lejars. Conclusion Les PVVI constituent une importante voie de derivation en cas d’obstacle ilio-cave, pelvien mais aussi encephalique. La correspondance neuro-veineuse explique les syndromes radiculaires du fait de la compression des racines a chaque etage metamerique par les veines foraminales dilatees. Ceci peut advenir en cas de thrombose ilio-cave et etre la cause de certaines sciatalgies de fin de grossesse.

La litterature sur l’insuffisance veineuse prend tres peu en consideration les varices du pied au profit de la varicose jambiere malgre la plainte esthetique et les possibles complications thrombotiques. Souvent les varices du pied sont dependantes du reflux tronculaire sus-jascent. Mais parfois, l’examen minutieux revele l’absence de connexion a l’etage jambier faisant de ces varices une atteinte distale et isolee dont les mecanismes physiopathologiques restent encore a etudier. Objectif Decrire les caracteristiques cliniques et echo-Doppler communes des varices isolees du pied sur une serie de 8 personnes. Methode Quinze pieds atteins de varices isolees ont ete identifies chez 8 patients indemnes de tout reflux saphenien. Les troubles de la statique plantaire ont ete recherches cliniquement puis confirmes par radiographies et empreintes. L’evaluation morpho-hemodynamique des veines du pied a ete realisee en trois etapes incluant les trois segments de la pompe plantaire : en distalite, au niveau de l’espace inter-metatarsien, en medio-plantaire puis au niveau du confluent calcaneen. Resultats Nous avons releve l’association constante entre varices du dos du pied et trouble de la statique plantaire. Deux caracteristiques communes meritent d’etre soulignees : – la dilatation constante des veines marginales et de la veine perforante du premier espace inter-metatarsien ; – la flexion des orteils provoque un flux Doppler anterograde enregistre sur la perforante du premier espace inter-metatarsien dirige vers les veines tibiales posterieures. Alors que la compression manuelle sous-malleolaire mediale provoque un flux a deux temps (retrograde puis anterograde) recueilli sur la meme perforante. Conclusions Ces resultats sont confortes par les etudes ayant demontre que lors de l’activite de la pompe veino-plantaire, le flux prevalent est dirige principalement vers les veines tibiales posterieures. Un contact anormal au sol de la semelle laterale lors de la marche contribue a une augmentation de la pre-charge des veines plantaires ayant pour consequence un defaut de vidange veineuse. Les mecanismes compensatoires pourraient mettre a contribution les perforantes avalvulees du pied, en particulier celle du premier espace inter-metatarsien jusqu’a creer une dilatation chronique et irreversible communiquant aux veines du dos du pied.

Background The “Adductor canal syndrome” has been described as an unusual cause of acute arterial occlusion inside the Hunter’s canal in young sportsmen. It may also produce a compressive neuropathy of the saphenous nerve. To our knowledge, femoral vein compression in the canal has never been reported. Objective To describe the anatomy, to propose a physiology of this canal, and to show that the femoral vein is much more exposed than the artery to compression inside this adductor hiatus, particularly at the outlet. Material and methods The whole adductor canal was exposed in 100 limbs for anatomical study following latex injection. A series of 200 phlebographies and 100 CT venograms were also analyzed. Results Anatomically, we found a musculotendinous band called the “vastoadductor membrane,” which jointed the adductor tendon to the vastus medialis in all the cases. The femoral vein, located more posteriorly, was frequently narrowed at this level. This band can create a notch with a venous stenosis at the outlet of the Hunter’s canal, usually located 12–14 cm above the femoral condyle. Two femoral valves constitute the landmark of the canal on the venograms: the lower is just below the outlet, 9 cm above the condyle. The second valve is 3 cm higher inside the canal. Functionally, the cadaveric simulations showed that the contraction of the adductor longus closes the hiatus, while the adductor magnus opens it. Our hypothesis is that Hunter’s canal prevents femoropopliteal axis reflux by synchronizing with calf pump ejection during ambulation. Conclusion Compression of the femoral vein inside the adductor’s canal is an underestimated and misdiagnosed cause of postural stenosis of the femoral vein. Ultrasound investigation of both limbs in patients with chronic venous disease (CVD) should be systematically carried out at this precise level in order to prevent future occlusion and onset of acute deep vein thrombosis.

A new technique for the packaging of IGBT modules has been developed. The components are sandwiched between two direct bond copper (DBC) substrates with aluminum nitride. Wire bonds are replaced with flip chip solder bumps, which allows cooling of components on both sides. Microchannel heat sinks are directly integrated in the package to decrease the thermal resistance of the module. Thus, a very compact module with high thermal performance is obtained. A prototype with two insulated gate bipolar transistors (IGBTs) and four diodes associated in parallel was realized and tested. In this paper, the innovative packaging technique is described, and results of thermal tests are presented.

Portal hypertension is characterised by the development of a collateral portocaval circulation. Among these venous reroutings, some are situated posteriorly in the left subphrenic compartment. These are the spontaneous splenorenal and gastrorenal anastomoses. Their incidence is estimated at around 16%. On the one hand, there are the direct shunts, which anastomose the spelling v. to the left renal v., of an anecdotal nature, and on the other the spontaneous indirect splenorenal shunts, characterised by the presence of a complete neurovascular pedicle traversing the gastrophrenic ligament. This relates to the gastric collateral v., which is connected to the left renal v. via the inferior v. of the left crus of the diaphragm and the middle capsular v., hence the name "gastro-phreno-capsulo-renal shunt". At an advanced stage of portal hypertension these splenorenal shunts may acquire a major caliber and behave like actual surgical shunts.

The PTC effect in doped BaTiO3 is usually ascribed to specific electrical properties of grain boundaries only. From microscopic four-probe electrical resistivity measurements, it is demonstrated that the bulk is also involved in this effect. To explain these new results, which conflict with the usual PTC theory, a model based on dipolar interaction is used.

Introduction L'equipe pluridisciplinaire du Centre Referent Pompes Ambulatoires d'Insuline a accompagne, depuis 2011, 20 patients (hors grossesse) porteurs d'un capteur de glucose en continu couple a la pompe, pour une duree de six mois. Materiels et Methodes L'equipe a retenu les criteres d'inclusion suivants : instabilite glycemique, hypoglycemies non ressenties, difficultes dans la gestion de l'alimentation et/ou la prise de decision concernant les ajustements d'insuline, demotivation a l'auto-surveillance de la glycemie. Apres accord des patients, l'equipe a transmis les connaissances techniques liees a ce nouvel outil « medical » et a assure un accompagnement de chacune des personnes a J15, J90 et J180. Durant cet accompagnement, nous avons pu constater, pour 80 % des patients, des changements vis-a-vis des croyances (ascension glycemique au moment des repas…), des comportements (gestion du resucrage, des activites physiques…) et du ressenti vis-a-vis de cet outil (materiel supplementaire…). Observations Durant cet accompagnement, nous avons pu constater, pour 80 % des patients, des changements vis-a-vis : des croyances (ascension glycemique au moment des repas…), des comportements (resucrage, gestion des activites physiques…) et du ressenti vis-a-vis du materiel (capteurs supplementaires…). Cet enregistrement continu de la glycemie est devenu un outil d'education actif qui a apporte au patient plus de securite, d'autonomie, de confort, de soutien. Cet outil est un veritable levier de changement et permet l'anticipation d'evenements. Au fil des mois, il y a eu un transfert du savoir medical vers une reelle appropriation de l'outil par le patient. En ce qui concerne les 20 % restants, 5 % des patients ont rencontre des difficultes pour faire confiance au materiel (discordance entre glycemie capillaire et glycemie interstitielle…), 15 % n'ont pas modifie leur gestion habituelle du traitement (peur persistante de l'hypoglycemie…) et, pour certains, l'Holter a ete une source d'anxiete (obsession du resultat ideal…). Conclusions Nous cherchons a connaitre, pour les patients ayant adhere au systeme, si les nouveaux savoirs, savoir-etre et savoir-faire, ont perdure ; et, pour les autres patients, si cette experience et cet accompagnement leur ont permis de se mettre en reflexion afin de modifier leurs croyances, representations ou comportements. Pour tous, il est indispensable de maintenir l'accompagnement dans le temps pour renforcer les changements.

The aim of this paper is to demonstrate the location of the venous foot pump using an anatomical study. Four hundred cadaveric feet were injected with green neoprene latex followed by a dissection. A coloured segmentation of the venous system was achieved. The Lejars’ concept of the venous sole of the foot is incorrect: the true blood venous reservoir of the foot is located deeply in the plantar veins, between the plantar muscles. The medial and mostly lateral plantar veins converge into the plexus shaped calcaneal crossroad, where the blood is ejected upwards into the two posterior tibial veins. In addition, the several medial perforators of the foot directly connect the deep system (medial plantar veins) to the superficial venous system (medial marginal vein). This forms a true ‘medial functional unit’ which is unique in the limb given its directional flow is from deep to superficial. In conclusion, the plantar veins play an important role in the physiology of the venous return since a venous reservoir of 25 mL of blood is mobilized upwards with each step during walking. Therefore, the impairment of the foot pump by a static foot disorder should be considered as an important risk factor for chronic venous disease, and should be evaluated and corrected in any patient with venous insufficiency.

Using photolithographic techniques, four-probe electrical resistivity measurements of Nb-doped BaTiO3 ceramics, at the microscopic scale, are presented from room temperature up to 180 degrees C. The PTC effect displayed by several grains exhibits an abrupt jump at the Curie temperature, followed by a monotonic quasi linear increase of the resistance. This behaviour looks quite different from the usual PTC effect observed on macroscopic ceramics. The jump is clearly due to a change of resistance within the bulk. It appears, from the microscopical results, that the bulk itself must be partially involved in the increase of resistance above T-c contrary to the generally accepted theory.

In order to investigate the bulk contribution to the global PTC effect encountered in doped BaTiO3, the four probes electrical resistance of a few grains has been measured from room temperature up to 180°C using photolythography. The results show that, with a decrease of the investigated area, the phase transition within the bulk, characterized by an abrupt step of resistance, gives an non negligible contribution to the PTC effect observed in those samples around the Curie temperature.

The head and vertebral column from two human cadavers were injected with a solution of gelatin and gadolinium (Dotarem®) and imaged using magnetic resonance imaging (MRI). Comparisons between gross anatomic slices and corresponding images of the lumbar vertebral column confirmed the usefulness of a paramagnetic agent for visualising the epidural venous plexus. This technique provides accurate images of the posterior longitudinal ligament.

DC electrical resistivity measurements along the c-axis of Nb-doped BaTiO3 single crystals are presented in a wide range of temperature, covering the four phases, with special attention to the rhomboedral one. The temperature dependence of the conductivity leads to convincing arguments in favour of a polaronic mechanism. Below the orthorhombic-rhomboedral transition point, a strong increase of the resistivity is observed. The correlation of this behavior with EPR analysis in the same temperature range, is consistent with a sharp trapping of the ''free'' electrons, when the temperature decreases.

In order to check the consistency of the well known Heywang model for explaining the PTC effect, DC resistivity, AC impedance and thermoelectric power measurements have been performed on Nb-doped BaTiO3 ceramics. It is found that the Heywang model can fit the shape of the experimental DC resistivity data, but it appears that the donor density in the grain is much lower than the nominal one, while impedance measurements emphasize the role of the grain boundary resistance. The thermoelectric power exhibits an anomalous behavior in contradiction with the usual semiconductivity mechanism of electrical transport.

In this paper, the authors present the modelling of the impedance variation of an inverter DC bus. Modelling is done by application of the PEEC method (partial element equivalent circuit) with an additional method for computing the local charge density (analytical formulas) in order to give the local capacity. This method has been implemented so as to extract the behaviour of the local charge density, specifically for busbar structure. Results obtained in the case of an approached busbar equivalent geometry are shown. A quantification of the edges importance for the charge repartition is presented, and so its link with the HF local capacitor influence. Moreover simulations of the values of the global DC bus impedance versus frequency are compared to measures.

The purpose of this work was to study an inferior lumbar venous system, which turned out to be the vertical component of the iliolumbar vein as defined in early works by Bourgery and Jacob, though there is a terminological ambiguity between the iliolumbar vein and the ascending lumbar vein in the literature. However, the iliolumbar vein is most commonly defined as a vein draining the fourth and fifth lumbar vertebral segments. Cadaver studies, including one injection-corrosion, and in vivo venograms were analyzed by visual inspection and measurements. Whether the injection was made via the axillary or the saphenous veins, the inferior lumbar vein was always filled, demonstrating that it is part of the vertebral venous system. An interruption or a plexiform shape of the venous system at the level of the third lumbar vertebra, and an increase in caliber as this vein runs downwards, allowed differentiating the inferior lumbar vein from the ascending lumbar vein. The inferior lumbar vein and the superior iliac vein drained into the iliac veins, either external or internal iliac vein, but typically into the common iliac vein, separately or with a single common trunk. This common trunk was observed in 92% of the dissected cases on the right side and in 46% on the left, whereas it was seen in 50% of the radiological studies on the right side and 52% on the left. Consequently, the inferior lumbar vein was the main component of the iliolumbar vein, and as such should be differentiated from the ascending lumbar vein. Clin. Anat. 20:545–552, 2007. © 2007 Wiley-Liss, Inc.

La carence en 25OH vitamine D au cours d’une hyperparathyroidie primaire peut rendre le diagnostic delicat et pose la question de sa substitution en preoperatoire. Ce deficit est susceptible d’aggraver les signes de l’hyperparathyroidie primaire en stimulant la croissance de l’adenome, en elevant le taux de PTH et en aggravant le risque fracturaire. Nous rapportons le cas d’un jeune homme âge de 23 ans, presentant des coliques nephretiques recidivantes, avec une hypercalcemie a 133 mg/L, une PTH a 257 ng/L, la 25OH vitamine D a 8 ug/L, phosphoremie 17 mg/L, calciurie des 24 h a 548 mg/L. Une hyperparathyroidie primaire par adenome parathyroidien inferieur gauche est confirmee avec comme retentissement des micro-lithiases renales (DMO normale, fonction renale normale). La recherche de mutation du gene NEM1 est en cours. En preoperatoire, une supplementation vitaminique et une cure de biphosphonates sont realisees. La chirurgie confirme l’adenome parathyroidien unique avec chute de la PTH en peroperatoire de 586 a 46,7 ng/L. Un mois plus tard on note une reaugmentation de taux de PTH a 286 ng/L en lien avec une carence vitaminique profonde a 5 ug/L, calcemie normale ecartant l’hypothese d’une recidive. La carence vitaminique parait aggraver le profil de l’hyperparathyroidie primaire : taille de l’adenome, taux de PTH pre- et postoperatoire, risque osseux. Le deficit en vitamine D doit etre compense des la periode preoperatoire, et poursuivi au-dela, afin de prevenir ces risques. Il faut ce pendant adapter les modalites de la vitaminotherapie au contexte de l’hyperparathyroidie.

Les adenomes somatotropes silencieux correspondent a une entite rare. Leur diagnostic se base sur un depistage par le dosage systematique de GH/HGPO et le l’IGF1, ou l’etude immunohistochimique. Nous rapportons le cas d’une patiente âgee de 41 ans, avec decouverte fortuite d’un macroadenome hypophysaire de 12 mm en raison de cephalees chroniques sans troubles visuels, aucun signe clinique d’acromegalie. En preoperatoire, il a ete diagnostique une hyperprolactinemie de deconnexion, un freinage partiel du cortisol (freinage faible), absence de freinage de la GH/HGPO et une IgF1 normale. L’etude immunohistochimique a confirme le caractere immuno-reactif vis-a-vis de la GH. Absence de mutation du gene AIP. En postoperatoire, on note l’absence de reliquat tumoral, un freinage satisfaisant de la GH/HGPO, un diabete insipide postoperatoire transitoire. Le bilan de retentissement de cette secretion occulte de la GH n’a montre qu’une dystrophie thyroidienne. La frequence de ces adenomes somatotropes silencieux est mal precisee a ce jour. La realisation systematique de l’immunohistochimie et de la GH/HGPO associee a l’IgF1 en preoperatoire permet d’identifier cette entite et d’organiser un suivi adapte.

Introduction Les veines perforantes (VP) du pied ont un mode de fonctionnement unique : contrairement a toutes les autres VP du membre inferieur, elles drainent le sang des veines profondes (veines plantaires) vers le reseau superficiel. Objectif Decrire l’anatomie des VP du pied qui sont des voies de drainage vers le reseau saphene lors de la systole plantaire. Materiel et methodes Quatre cents membres de 200 sujets non embaumes ont ete injectes au latex neoprene apres lavage a l’eau savonneuse. Une dissection anatomique a ete realisee puis une segmentation coloree. Cent phleboscanners ont egalement ete analyses apres reconstruction 3D par VRT. Resultats Les veines plantaires se drainent directement dans les veines tibiales posterieures a partir du confluent calcaneen, mais aussi dans les veines tibiales anterieures par l’intermediaire de la VP dorsale du pied. Mais les connexions superficielles sont les plus interessantes car les plus mal connues : – avec la veine marginale mediale, origine de la grande saphene a la cheville par 4 perforantes : sous-malleolaire, naviculaire, cuneenne et du premier espace inter-metatarsien. Elles constituent en quelque sorte avec les veines plantaires mediales un complexe fonctionnel medial ; – avec la petite saphene et sa branche achileenne : ce sont la perforante calcaneenne et les PV externes (sous et inter-tendineuses des fibulaires lateraux) qui sont une voie de sortie importante des grosses veines plantaires laterales. Ceci constitue un second complexe fonctionnel lateral. Conclusion Ces donnees anatomiques expliquent le flux ascendant enregistre au Doppler dans la partie basse des 2 troncs saphenes lors de la systole plantaire. La responsabilite des VP du pied doit etre prise en compte dans les varices du pied. L’exploration des veines plantaires et des PV du pied devrait faire partie du bilan cartographique et hemodynamique de tout patient insuffisant veineux.

The miniaturization and improving performance of electronic devices has lead to increasing power densities in electronic systems. Consequently, the thermal environment has become a main issue in their performance and reliability. The use of flat miniature heat pipes has been investigated for transferring the heat over distances or to spread it over a larger surface area to avoid hot spots on the device. The interest of silicon etching techniques for heat pipe manufacturing is that such heat pipes can be very compact, very light and have better heat transfer capacities than metallic heat pipes. In this paper the structure of a flat radial structure silicon heat pipe is presented. A one dimensional two-phase flow model has been developed in order to optimize the performances of the radial grooved silicon heat pipe. Then an experimental study investigates the thermal performance of a realized prototype. The thermal transfer capacities achieved are in the range 50-70 W depending on the working temperature

Subcutaneous emphysema and mediastinitis are rarely reported complications of tonsillectomy.We describe two patients who developed subcutaneous emphysema, one of them with mediastinitis, within a few days after tonsillectomy. The diagnosis was based on the clinical presentation and confirmed by computed tomography (CT). For the patient without mediastinitis, the emphysema disappeared after a short period of reintubation and administration of antibiotics. For the patient with mediastinitis, surgical drainage of a cervico-mediastinal purulent collection was necessary to obtain healing.The events leading to subcutaneous emphysema and mediastinitis have not been entirely clarified. They probably include direct introduction of air into the neck via either the tonsillar bed or a laryngeal or pharyngeal wound caused by intubation. The clinical presentation, treatment and possible pathophysiology of subcutaneous emphysema and medisastinits are discussed.Emphysema and mediastinitis after tonsillectomy occur seldomly. If rapidly recognised and appropriately managed, mortality can be avoided.