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ABSTRACT: Introduction Vascular surgery affects, among other factors, vessel geometry and might result in significant flow changes. For this reason a basic understanding of flow behavior at bifurcations plays an important role for microsurgeons. The aim of the present work was to establish an experimental model that enables rheological analyses of microvascular techniques.Methods Laser Doppler anemometer (LDA) measurements in a total of four cross-sections of a true-to-scale silicone model were performed. The model was installed in a circulatory experimental setup that simulates the physiologic human blood flow. The flow velocity data measured with the LDA system was processed and analyzed with an image-processing system.Results The flow curve at each cross-section was recorded for sevem cycles. A physiologic flow separation at bifurcational level was seen. Maximal and minimal horizontal velocities of all measurement points were between 0.32 and -0.15 m/s. No signs of turbulentlike flow were seen in the cross-sections distal to the bifurcation. A total, centrally located backflow in the diastolic phases in all four cross-sections was registered, resembling an oscillatorylike flow.Conclusions The LDA analysis represents a valid experimental method for rheological evaluation of microvessels. Due to its unique high spatial and temporal resolution, it represents a worthwhile alternative to other flow investigations.
Journal of Reconstructive Microsurgery 04/2013; · 1.43 Impact Factor
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ABSTRACT: Das Gardner-Syndrom zeichnet sich durch die Trias intestinale Polypose, multiple Knochen- und Weichteiltumoren aus. Unbehandelt
führt die Erkrankung bei allen Patienten zur Entstehung von gastrointestinalen Karzinomen. Obwohl eine Heilung nicht möglich
ist, kann die Progredienz der Erkrankung durch engmaschige Kontrollen und eine prophylaktische Kolektomie aufgehalten werden.
Multiple Osteome der Kiefer- und Schädelknochen sind eine für die Diagnosestellung richtungsweisende und häufige extraintestinale
Manifestation. Da die extraintestinalen Symptome meist lange vor der intestinalen Polypose auftreten, kann die Kenntnis des
Krankheitsbilds zu einer prognostisch entscheidenden Frühdiagnose beitragen.
Gardner’s syndrome is characterized by the triad of intestinal polyposis accompanied by multiple hard- and soft-tissue tumors.
Untreated, all patients will develop gastrointestinal cancer by the age of 40. Although incurable, progression can be prevented
by close monitoring and prophylactic colectomy to prevent malignancy. Multiple osteomas of the head and jaw bones are common
extraintestinal manifestations of Gardner’s syndrome and can be helpful in the diagnostic work-up. The disease pattern should
be known to the treating physician, since extraintestinal manifestations usually occur long before intestinal polyposis and
early diagnosis is critical for the prognosis.
SchlüsselwörterGardner-Syndrom–Familiäre adenomatöse Polypose–Osteom–Epidermoidzyste–Adenomatöse Polyposis coli
KeywordsGardner’s syndrome–Familial adenomatous polyposis–Osteoma–Epidermoid cyst–Adenomatous polyposis coli
HNO 05/2012; 59(5):523-527. · 0.40 Impact Factor
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ABSTRACT: FallEin 25-jhriger Patient wurde uns mit Fieber, Schluckbeschwerden und reduziertem Allgemeinzustand nach 1-wchiger antibiotischer Vorbehandlung vom Hauszahnarzt mit einer seit 2Wochen bestehenden submandibulren Schwellung rechts und einem karisen und apikal beherdeten Zahn48 vorgestellt. Bei der operativen Entfernung dieses Weisheitszahnes, verbunden mit der vermeintlichen Abszessinzision von intra- und extraoral, floss weder Eiter, noch war die Schwellung rcklufig. In der anschlieenden CT-Diagnostik imponierten ausgedehnte Lymphknotenkonglomerate submandibulr rechtsbetont. Das in einem erneuten Eingriff entnommene Gewebe brachte die Diagnose eines hyalin-vaskulren Morbus Castleman.BefundeIm daraufhin durchgefhrten Staging konnten keine weiteren pathologischen Befunde erhoben werden. Der klinische Zustand des Patient besserte sich postoperativ zunehmend. Histologisch wies der vorgefundene hyalin-vaskulre Typ des Morbus Castleman abnorme Follikel und eine Vermehrung von Kapillaren im interfollikulren Raum auf. Die Lymphfollikel waren in ihrer Zahl vermehrt und wurden von Gefen mit hyalinisierten Wnden strahlenfrmig penetriert sowie von mehreren Schichten kleiner Lymphozyten zwiebelschalenartig umgeben (onion skin).SchlussfolgerungBeim Morbus Castleman handelt es sich um ein in seiner tiologie und Pathophysiologie weitgehend ungeklrtes, seltenes und heterogenes Krankheitsbild. Obwohl berwiegend durch einen benignen Verlauf gekennzeichnet, kann die Erkrankung wie in dem vorliegenden Fall je nach Lokalisation zu erheblichen Problemen in der Diagnostik fhren. Insbesondere bei unklaren, aber auch abszessverdchtigen Schwellungen in der Kopf-Hals-Region sollte daher an diese seltene Differenzialdiagnose gedacht werden. In Anbetracht der beschriebenen Rezidive und des Potenzials zur malignen Entartung ist eine langjhrige Nachbetreuung dieser Patienten erforderlich.Case reportA 25-year-old patient with fever, dysphagia, and reduced general condition was referred to our department by his dentist after 1week of antibiotic therapy. He presented with a painful palpable mass in the right lower jaw that had developed 2weeks before. The orthopantomogram showed a caries and periapical lesion at the right lower wisdom tooth. During extraction of the tooth and putative intra- and extraoral abscess incision, no pus could be drained and the mass persisted. CT scans then revealed lobulated soft tissue masses on both sides of the neck with the main focus on the right side. In an additional operation with excision of the mass, Castlemans disease of the hyaline vascular type was diagnosed.Histopathologic findingsStaging could not detect further pathological findings and the patients postoperative general condition improved continuously. The histological features of the hayline vascular type of Castlemans disease were characterized by multiple germinal centers surrounded by circumferentially arranged layers of small lymphocytes interconnected by a prominent vascular stroma with occasional plasma cells (onion skin).ConclusionCastlemans disease is a rare and yet poorly understood disease, characterized by inhomogeneous growth of lymphoid tissue. Mostly benign it remains a diagnostic challenge before histological investigation. In unclear submandibular swellings and neck lumps assumed to be an abscess, this rare differential diagnosis must be considered. Facing recurrence and potential for malignancy, follow-up of the patients over several years is necessary.
Mund- Kiefer- und Gesichtschirurgie 04/2012; 9(2):121-125.
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ABSTRACT: HintergrundZu den Hauptrisiken beim Facelifting gehrt neben der Nachblutung und der Nervverletzung auch das Auftreten von Hautnekrosen. Es wurde deshalb der Frage nachgegangen, ber welche Gefe der Hautlappen beim klassischen Facelifting mit Blut versorgt wird und wie ausgedehnt die Unterminierung erfolgen darf, bevor eine Minderperfusion des Lappens zu erwarten ist.Material und MethodeAn sechs Leichen wurden selektive Farbstoffeinspritzungen in die ste der A. carotis externa vorgenommen, um zunchst die Lage ihrer vaskulren Territorien in Bezug auf die Facelifting-Region zu bestimmen. An weiteren zwlf Leichen wurden dann unterschiedlich weit mobilisierte Facelift-Hautlappen gebildet, bevor die Injektionen in die ermittelten Gefe erfolgten.ErgebnisseBei den Einspritzungen in die ste der A. carotis externa war festzustellen, dass die A. facialis ber Perforansgefe im paranasalen, perioralen und submentalen Bereich und die A. transversa faciei ber ein Perforansgef unterhalb des Jochbeinkrpers die Facelifting-Region mit Blut versorgen. Bei den Hautlappen ergab sich nach klassischer Unterminierung trotz der damit verbundenen Ausschaltung des Stromgebietes der A. transversa faciei eine Anfrbung des prparierten Hautlappens im Bereich der Wange und oberen Halsregion ber die im zentrofazialen Bereich erhaltenen Perforansgefe der A. facialis.SchlussfolgerungWir leiten aus unseren Ergebnissen ab, dass zur Vermeidung von Minderperfusionen der Hautlappen beim Facelifting nicht ber die Nasolabialfalte hinaus unterminiert werden sollte.BackgroundBesides nerve injuries or hematomas, one of the main risks of face lift surgery is the development of skin necrosis. We therefore investigated which arteries contribute to the blood supply of the face lift skin flap and how extensively mobilization can be performed before arterial cutaneous circulation is endangered.Material and methodIn six cadavers, selective dye injections into the branches of the carotid external artery were performed to determine the location of their vascular territories in relation to the face lift region. In another 12cadavers, face lift flaps were raised with different extension of the undermined skin area before dye injections were performed.ResultsIt was shown that the facial artery provides blood supply to the area of the face lift flap by perforating vessels in the paranasal, perioral and submental regions and the transverse facial artery by a perforating vessel below the malar bone prominence. Although the perforating vessel of the transverse facial artery was transected by standard mobilization, the face lift flaps were sufficiently perfused via the paranasal and perioral perforating vessels of the facial artery alone.ConclusionWe conclude that undermining of the face lift flap should not exceed the nasolabial fold to preserve the perforating vessels of the facial artery in the centrofacial region.
Mund- Kiefer- und Gesichtschirurgie 04/2012; 9(1):1-5.
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ABSTRACT: Lasertherapie. Seit Einführung der Lasertherapie für die Behandlung von Hämangiomen und vaskulären Malformationen hat die operative Therapie
in der Primärbehandlung immer mehr an Bedeutung verloren. Besonders Hämangiome, aber auch venöse Malformationen und Lymphangiome
werden heute in der Regel einer primären Lasertherapie zugeführt, wobei besonders der Nd:YAG-Laser mit perkutaner oder transkutaner
Applikationstechnik oft zu guten Ergebnissen führt.
Chirurgische Verfahren. Chirurgische Verfahren kommen meist nach mehrmaliger Laserbehandlung erst sekundär im späten Kindes- oder Erwachsenenalter
zur Anwendung und bestehen aus der Exzision von Restbefunden oder plastischen Korrekturoperationen. Besonders bei subkutan
gelegenen Gefäßanomalien und bei erfolgloser Lasertherapie mit weiterhin schnell wachsenden Hämangiomen besteht jedoch auch
heute noch eine klare Indikation zur chirurgischen Therapie, die selbst bei ausgedehnten Befunden eine blutungsarme und sichere
Tumorentfernung ermöglicht.
Fallberichte. Anhand von 3 Kasuistiken soll auf die Notwendigkeit einer operativen Intervention hingewiesen werden, durch die drohende
Komplikationen wie Erblindung, Läsion des N. facialis oder letaler Ausgang bei massiver Einblutung verhindert werden konnten.
Laser therapy. Since the introduction of laser therapy for treatment of hemangiomas and vascular malformations, primary surgical therapy
has gradually lost importance. Particularly hemangiomas, but also venous malformations and lymphangiomas, are nowadays primarily
treated by different types of lasers. Especially the Nd:YAG laser with a percutaneous or transcutaneous application technique
often leads to satisfying results.
Surgical therapy. Surgical therapy is mostly used secondarily in late childhood or in adults after several laser applications for excision
of residual scars or other corrective procedures. Despite these improvements in laser therapy, there is still an indication
for primary surgical treatment in subcutaneous vascular malformations and in rapidly growing hemangiomas after unsuccessful
laser therapy. Even in large vascular anomalies, safe excision with only a little blood loss is possible if the tumors are
encapsulated.
Case reports. In this paper we want to point out the necessity of primary surgery in three children in whom complications such as loss
of sight, facial nerve palsy, and a lethal outcome due to massive hemorrhage in a cystic lymphangioma could be avoided.
Hämangiom Vaskuläre Malformation Lymphangiom Operative TherapieHemangioma Vascular malformation Lymphangioma Surgical treatment
Mund- Kiefer- und Gesichtschirurgie 04/2012; 6(5):303-308.
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ABSTRACT: HintergrundBotulinumtoxinA ist inzwischen eine bewhrte Methode zur Behandlung des gustatorischen Schwitzens (gustatorische Hyperhidrose, Frey-Syndrom). Klare Empfehlungen zur Dosierung dieses Toxins liegen jedoch derzeit noch nicht vor. Das Ziel der vorliegenden prospektiv randomisierten Therapiestudie war es daher, BotulinumtoxinA an einem Patientengut der Klinik fr Mund-, Kiefer- und Gesichtschirurgie des Knappschaftskrankenhauses Bochum-Langendreer zu untersuchen. Folgende Kriterien wurden dabei bercksichtigt: die Wirksamkeit, die geeignete Dosis bei maximaler Wirkdauer sowie die Patientenzufriedenheit und unerwnschte Wirkungen.Patienten und MethodeZwanzigPatienten mit einem ausgeprgten Frey-Syndrom bei Zustand nach Operationen der Ohrspeicheldrse wurden mit dem Jod-Strke-Test nach Minor untersucht. Die gustatorischen Hautareale wurden im Anschluss an die intrakutanen Injektionen von BotulinumtoxinA ber einen Zeitraum von einem Jahr nachuntersucht. Die Patienten wurden randomisiert zwei verschiedenen Behandlungsgruppen zugefhrt: GruppeI (n=10) erhielt 2MU/cm2, GruppeII (n=10) erhielt 3MU/cm2.ErgebnisseDie mittlere sekretorische Flche in den beiden Patientengruppen lag bei 399 bzw. 3212cm2. Die einmalige Injektion von 3MU Botulinumtoxin A fhrte zu einer nahezu vollstndigen Blockade des gustatorischen Schwitzens fr den gesamten Beobachtungszeitraum von einem Jahr. In der Patientengruppe, die mit 2MU BotulinumtoxinA pro cm2 behandelt worden war, zeigten sich 44% der gustatorischen Flche noch sekretorisch aktiv, sodass diesen Patienten ein zweites Mal BotulinumtoxinA injiziert werden musste.SchlussfolgerungDie intrakutane Injektion von BotulinumtoxinA stellt ein hocheffektives, praktikables und minimalinvasives Verfahren zur Behandlung des Frey-Syndroms dar. In der vorliegenden Studie konnte erstmals gezeigt werden, dass bei einer Dosis von 3MU/cm2 BotulinumtoxinA eine vollstndige und zuverlssige Blockade des gustatorischen Schwitzens fr mindestens 12Monate zu erreichen ist. Diese Dosis kann daher fr die Therapie dieses Krankheitsbildes empfohlen werden.BackgroundBotulinum toxin A has meanwhile become a proven method for treatment of gustatory sweating (focal hyperhidrosis, Freys syndrome). Clear-cut recommendations regarding dosage of botulinum toxin A in Freys syndrome are currently not available. The aim of this prospective randomized study therefore was to investigate botulinum toxin A with respect to its efficacy in Freys syndrome, the ideal dose yielding maximal duration of the effect, and patient contentedness as well as unwanted side effects in patients of the Clinic of OMF Surgery at the Ruhr-University of Bochum.Patients and methodTwenty patients suffering from severe Freys syndrome as a result of operations of the parotid gland were examined with the starch iodine test according to Minor. The gustatory skin areas were re-examined after intracutaneous injection of botulinum toxin A for up to 1year. The patients (n=20) were randomly assigned to two different treatment groups (group I: 2MU/cm2, n=10; group II: 3MU/cm2, n=10).ResultsMean sweating skin areas in the two treatment groups ranged between 399 and 3212cm2, respectively. A single injection of 3MU botulinum toxin A resulted in a nearly complete blockade of gustatory sweating for the observation period of 1year. In the group treated with 2MU botulinum toxin A, 44% of the total gustatory skin areas were still sweating, thus necessitating a second injection of botulinum toxin A in these patients.ConclusionIntracutaneous injection of botulinum toxin A represents a highly effective and minimally invasive procedure for the treatment of Freys syndrome. This study shows for the first time that a dosage of 3MU/cm2 of botulinum toxin A achieves a complete and reliable blockade of gustatory sweating lasting for at least 12months. This dose may therefore be recommended for treatment of this syndrome.
Mund- Kiefer- und Gesichtschirurgie 04/2012; 8(6):369-375.
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ABSTRACT: Fragestellung. Ziel der vorliegenden Untersuchung war, die Effekte der Sauerstoff tragenden freien Hämoglobinlösung (Diaspirin-crosslinked-Hämoglobin,
DCLHb) auf die kapillare Perfusion sowie die Oxygenation im quergestreiften Hautmuskelgewebe nach kritischer Ischämiezeit
und nachfolgender Reperfusion zu analysieren.
Material und Methode. Die kapillare Gewebeperfusion wurde anhand der funktionellen Kapillardichte im Hautmuskel des syrischen Goldhamsters quantitativ
vor der Induktion einer 4-stündigen Ischämie sowie nach 0,5 h, 2 h und 24 h Reperfusion mittels intravitaler Fluoreszenzmikroskopie
erfasst (n=8 pro Versuchsgruppe). In separaten Tieren wurde nach demselben Versuchsansatz mit der Mehrdrahtoberflächenelektrode (MDO,
Eschweiler, Kiel) die Gewebeoxygenation gemessen (n=8 pro Versuchsgruppe). Die Tiere der Testgruppe (n=8) erhielten 15 min vor der Reperfusion eine Kurzinfusion von 5 ml/kg KG DCLHb (Diaspirin-crosslinked-Hämoglobin, 10 g/dl,
Baxter, IL, USA). Die Kontrolltiere (n=8) erhielten äquivalente Dosen einer isotonen Kochsalzlösung (Braun, Melsungen).
Ergebnisse. Die funktionelle Kapillardichte als Maß für die Länge von erythrozytenperfundierten Kapillaren pro Beobachtungsfeld war bei
den Kontrolltieren in der Reperfusionsphase dramatisch vermindert, während bei den mit DCLHb behandelten Tieren signifikant
höhere Werte nachweisbar waren (p<0,05). Diese Beobachtung spiegelte sich in einer vollständigen Erholung des Gewebe-pO2 bei den Behandlungstieren wider, was in Kontrolltieren nicht erreicht wurde.
Schlussfolgerungen. Die Ergebnisse dieser Studie zeigen, dass die Sauerstoff tragende Lösung DCLHb nach kritischer Ischämie und Reperfusion die
nutritive Perfusion und Gewebeoxygenation gegenüber kristalloiden Lösungen verbessert. Die Anwendung derartiger Lösungen scheint
unter den klinischen Bedingungen einer kritischen Ischämie daher als viel versprechender adjuvanter therapeutischer Ansatz.
Aim. The aim of the present study was to investigate the effects of the oxygen-carrying hemoglobin solution DCLHb (diaspirin-crosslinked
hemoglobin) on microvascular perfusion and tissue oxygenation in striated skin muscle after the induction of critical ischemia
followed by reperfusion.
Material and Methods. Using intravital fluorescence microscopy the functional capillary density was analyzed in the striated skin muscle of Syrian
golden hamsters before the induction of a 4-h period of ischemia and again after 0.5 h, 2 h and 24 h of reperfusion (n=8 in each group). In other animals (n=8 in each group), the identical protocol was applied to determine tissue oxygenation by means of the multi-wire surface electrode
(MDO, Eschweiler, Kiel, Germany). Animals in the treatment group (n=8) received a bolus infusion of 5 ml of DCLHb per kg of body wt. (10 g/dl; Baxter, Ill., USA) 15 min before reperfusion.
Control animals (n=8) received equivalent volumes of isotonic saline (Braun, Melsungen, Germany).
Results. Functional capillary density was dramatically reduced in control animals, while in DCLHb-treated animals significantly higher
values were observed. Efficient restoration of tissue PO2 was also seen in DCLHb-treated animals and not in control animals.
Conclusions. These results show that the oxygen-carrying solution DCLHb is significantly more efficient than the commonly used crystalloid
solutions in restoration of tissue PO2 after ischemia–reperfusion. The use of this solution therefore appears promising as a means of protecting the tissue put
at risk by ischemia from reperfusion damage.
Ischämie Reperfusion Sauerstoff tragende Lösungen DCLHb Mikrozirkulation GewebeoxygenationIschemia-reperfusion Oxygen-carrying solution DCLHb Microcirculation Tissue oxygenation
Mund- Kiefer- und Gesichtschirurgie 04/2012; 7(1):31-35.
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ABSTRACT: HintergrundNach Einführung des mikrochirurgischen Fibulatransplantats im Jahr 1975 durch Taylor und erstem Einsatz im Kieferbereich 1989
durch Hidalgo hat sich dieses Transplantat zu einem Grundpfeiler für die Rekonstruktion des Unterkiefers bei ausgedehnten
oromandibularen Defekten etabliert. Voraussetzung für die Anwendung dieses Transplantats ist allerdings der Nachweis einer
intakten 3-Gefäß-Versorgung des Unterschenkels, um insbesondere bei Rauchern die Gefahr einer später auftretenden Mangeldurchblutung
des Fußes zu minimieren. Dieser Nachweis wurde bisher mit der invasiven DSA-Technik erbracht. Die Fortschritte auf dem Gebiet
der Magnetresonanzangiographie (MRA) ermöglichen jedoch zunehmend eine primäre Gefäßdiagnostik mit nichtinvasiven Untersuchungsverfahren.
Ziel der vorliegenden prospektiven Untersuchung war, die Frage zu beantworten, ob die MRA normvariante Gefäßverläufe und pathologische
Gefäßstenosen der Unterschenkelarterien zuverlässig darstellen und damit die konventionelle digitale Subtraktionsangiographie
(DSA) ersetzen kann.
Material und MethodeIn einer prospektiven Studie wurden bei 15 Patienten vor Entnahme eines Fibulatransplantats eine konventionellen DSA und postoperativ
eine MRA der Unterschenkel mit i. v. Kontrastmittelgabe angefertigt. Alle Aufnahmen wurden verblindet und einer Auswertung
durch 3 Radiologen zugeführt. Die Beurteilung des Gefäßstatus erfolgte in Bezug auf atherosklerotische Veränderungen, Stenosen,
hypoplastische Gefäße, Gefäßokklusionen und allgemeine Gefäßanatomie.
ErgebnisseDie hohe Auflösung der MRA ermöglichte eine sichere Beurteilung aller 3 Hauptgefäße des Unterschenkels. Fehlende und hypoplastische
Gefäße, Stenosen und atherosklerotische Veränderungen konnten eindeutig dargestellt werden und deckten sich mit den Befunden
der DSA.
SchlussfolgerungDie MRA der Unterschenkel ermöglicht eine sichere Beurteilung des Gefäßstatus und ist aufgrund des geringeren Untersuchungsrisikos,
der ambulanten Durchführbarkeit und der fehlenden Strahlenexposition der DSA in dieser Fragestellung vorzuziehen.
BackgroundSince the introduction of the fibula flap by Taylor in 1975, and its first application in the lower jaw by Hidalgo in 1989,
it has become an option of first choice in mandibular reconstruction of large oromandibular defects. Perfusion of the osteomyocutaneous
fibula transplant is based on the peroneal artery. To avoid postoperative ischaemia of the lower leg after sacrificing this
artery, especially in smokers, adequate perfusion must be guaranteed preoperatively by radiological evaluation. Progress in
the field of magnetic resonance angiography (MRA) enables an increasing number of primary non-invasive evaluations of vessels.
The aim of this prospective study was to answer the question of whether MRA enables a accurate representation of anatomical
variation and pathological stenoses of the lower leg vessels and can therefore replace conventional digital subtraction angiography
(DSA).
Materials and methodsWe carried out conventional DSA of the lower leg before raising a fibula transplant and postoperative MRA with contrast medium
in a prospective study with 15 patients. Vessels were assessed for atherosclerotic, occlusive or hypoplastic changes and anatomical
variations by three radiologists.
ResultsHigh resolution of MRA enables a reliable judgement of the lower leg vessels. Hypoplastic vessels, stenoses, occlusion or
atherosclerotic changes of the vessels could definitely be detected by MRA just as by DSA. Thus, all patients without these
diagnosed contraindications could be operated successfully.
ConclusionMRA of the lower leg enables a definitive determination of the vessel quality and the site of preference for harvesting the
flap. Because MRA is a low risk procedure, can be carried out on an outpatient basis and causes no radiation load, it should
be preferred to conventional DSA.
SchlüsselwörterMagnetresonanzangiographie–Digitale Subtraktionsangiographie–Vaskularisierte Fibulatransplantate–Präoperative Gefäßdarstellung–Mikrochirurgie
KeywordsMagnetic resonance angiography–Digital subtraction angiography–Free fibular bone grafts–Reconstructive surgical procedures–Microsurgery
Mund- Kiefer- und Gesichtschirurgie 04/2012; 7(4):246-253.
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ABSTRACT: FragestellungIn der Literatur werden Monitoringverfahren hufig in zwei Hauptgruppen unterteilt: Messungen zur Gewebeperfusion und solche zur Gewebeoxygenierung. Mit dem O2C (oxygen to see) steht nun erstmals ein Gert zur Verfgung, das beide Messmethoden vereint. In einer prospektiven Studie sollte untersucht werden, ob hiermit eine notwendige Revision mikrochirurgischer Transplantate frhzeitig erkannt oder auch eine unntige Revision vermieden werden kann. Weiterhin stellte sich die Frage, ob Grenzwerte fr den erfolgreichen Verlauf eines Lappentransfers angegeben werden knnen und ob sich diese bei den verschiedenen Transplantattypen unterscheiden.Patienten und MethodeIn einer prospektiven Studie wurden 82 mikrochirurgische Transplantate (61 fasziokutane Radialislappen und 21 osteokutane Fibulalappen) einem definierten Monitoring ber 14Tage unterzogen.ErgebnisseBei 12 (14,6%) von 82 freien mikrochirurgischen Transplantaten konnten Perfusionsstrungen gemessen werden. In 7Fllen erfolgte eine Revision, die in 5Fllen zur Rettung der Transplantate fhrte. Insgesamt waren 5Transplantatverluste (3 Radialis- und 2 Fibulatransplantate) zu verzeichnen. Die Gesamterfolgsrate betrug somit 93,4%. Durch das O2C-Gert wurden vense Okklusionen anhand einer Zunahme der Hmoglobinkonzentration um mehr als 30% und arterielle Perfusionsstrungen anhand der rapiden Abnahme des Blutflusses und der Hmoglobinoxygenierung in allen Fllen frhzeitig und vor der klinischen Manifestation erkannt. Als kritische Untergrenze fr eine ausreichende Transplantatversorgung ergaben sich fr Radialistransplantate eine Hmoglobinoxygenierung von 15%, ein oberflchlicher Flow von 10AU und ein tiefer Flow von 20AU. Fr Fibulatransplantate wurden eine Hmoglobinoxygenierung von 10%, ein oberflchlicher Flow von 5AU und ein tiefer Flow von 15AU als untere Grenzwerte festgestellt.SchlussfolgerungDas perioperative Monitoring mit dem O2C-Gert schliet durch die kombinierte Anwendung von Laser-Doppler-Flussmessung und Gewebespektrometrie in einer Messsonde die Lcke zwischen zwei etablierten Monitoringmethoden. Die simultane nichtinvasive Erfassung von Hmoglobinoxygenierung, Hmoglobinkonzentration, Blutfluss und Blutflussgeschwindigkeit in zwei verschiedenen Gewebetiefen ermglicht eine Verbesserung der Erfolgsquote des mikrochirurgischen Gewebetransfers.AimIn the literature currently available monitoring devices are usually divided into two major groups: those for monitoring perfusion and those for measuring tissue oxygenation. The O2C (oxygen to see) system combines these two ways of monitoring free flap viability. The aim of this prospective study was to determine the necessity of flap revision and when unnecessary revision can be avoided. Another point of interest was the question of whether critical values for the successful course of free flaps could be defined and in addition whether such values would differ for different flap types.Patients and methodsIn a prospective study 82 free flaps (61 radial forearm flaps and 21 fibula flaps) were monitored with the O2C monitoring unit. Measurements were carried out intraoperatively and postoperatively up to 14days.ResultsPerfusion compromise occurred in 12 (14.6%) of 82 monitored free flaps. Operative exploration was performed in seven cases, in five of them successfully. Five flaps (three radial forearm and two fibula flaps) were lost due to vascular compromise, which led to an overall success rate of 93.4%. Venous congestion was identified by a rapid increase in hemoglobin concentration of more than 30%. An abrupt decline of blood flow and hemoglobin oxygenation indicated arterial occlusion. Vascular complications were detected in all cases prior to clinical assessment with no false positive or negative results. For radial forearm flaps a hemoglobin oxygenation of 15%, a superficial flow of 10AU, and a deep flow of 20AU were identified as minimum values for flap viability. For fibula flaps a hemoglobin oxygenation of 10%, a superficial flow of 5AU, and a deep flow of 15AU were determined as minimum values.ConclusionO2C combines laser Doppler flowmetry and tissue spectrophotometry and for the first time allows simultaneous measurement of the microcirculatory parameters including blood flow, flow velocity, hemoglobin concentration, and hemoglobin oxygenation. We found this new noninvasive technique to be a reliable and accurate method for evaluating flap viability and improving the success rate in free flap transfer.
Mund- Kiefer- und Gesichtschirurgie 04/2012; 9(5):290-299.
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T Steiner,
S Raith,
S Eichhorn,
S Doebele,
S Trainotti,
S Müller,
M Eder,
L Kovacs,
R Burgkart, K-D Wolff,
F Hölzle
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ABSTRACT: OBJECTIVES: Biomechanical loading on human mandibles was performed and a new optical measurement device was introduced for the quantification of interfragmentary movement in fractured mandibles stabilized with different osteosynthesis systems. MATERIALS AND METHODS: Comparison tests were performed with monocortical non-locking double plates and bicortical single locking plate. For the experiments on a specialized test bench, 18 ex vivo fractured human cadaveric mandibles were tested. Interfragmentary motion was detected in all three spatial dimensions using the optical measurement device PONTOS®. The movement was investigated over increasing incisal force and one summarized parameter was investigated. RESULTS: For the maximal tested load of 300 N m, the resultant interfragmentary movements in the two investigated groups were 2.96 ± 1.85° for the fixation with two conventional miniplates (six hole, profile 1.0 mm) and 4.53 ± 2.49° for single bicortically fixed locking plates (four hole, profile 1.5 mm). For both plate systems, we used the 2.0 mm screw system. CONCLUSIONS: The test bench in combination with the new optical device PONTOS(®) can test the primary stability of osteosynthesis. We offer a solution to the problem of rate of twist of the mandible as well as typical rotational problem in recent measurements. Further, the method can be used for development of new osteosynthesis products. CLINICAL RELEVANCE: Pseudoarthrosis formation is a common problem based on unsatisfying fixation of the fracture gap. The here presented combination of mechanical tests and numerical simulations can provide support for an improved treatment of fractured mandibles.
Clinical Oral Investigations 12/2011; · 2.36 Impact Factor
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British Journal of Oral and Maxillofacial Surgery 07/2011; 49(5):412. · 1.95 Impact Factor
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ABSTRACT: Gardner's syndrome is characterized by the triad of intestinal polyposis accompanied by multiple hard- and soft-tissue tumors. Untreated, all patients will develop gastrointestinal cancer by the age of 40. Although incurable, progression can be prevented by close monitoring and prophylactic colectomy to prevent malignancy. Multiple osteomas of the head and jaw bones are common extraintestinal manifestations of Gardner's syndrome and can be helpful in the diagnostic work-up. The disease pattern should be known to the treating physician, since extraintestinal manifestations usually occur long before intestinal polyposis and early diagnosis is critical for the prognosis.
HNO 05/2011; 59(5):523-7. · 0.40 Impact Factor
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ABSTRACT: The aim of the study was to develop a reliable and reproducible arterial aneurysm model for microsurgical training and further research with dimensions comparable to those encountered in aneurysms in humans.
The arterial aneurysm models were created microsurgically at the bifurcation of the abdominal aorta using a graft of the carotid artery in 20 Wistar rats.
The aneurysms were created successfully and no complications occurred. The average volume of this arterial aneurysm model was 35.19±5.64 mm (3). The time required to create this kind of aneurysm was 192±14.4 min. The central zone of blood inflow into the aneurysm was not affected by any thrombus formation.
The presented model at the aortic bifurcation in the rat is reliable and immediately available for microsurgical and technical training as well as for scientific studies on aneurysms. Since this kind of model also reproduces arterial aneurysms, basic techniques such as suturing and microtechniques needed for the dissection and repair of vessels can be taught during its creation.
Central European neurosurgery 02/2011; 72(1):38-41. · 0.84 Impact Factor
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ABSTRACT: In a bilateral sagittal split osteotomy (BSSO) mechanical irritation of the inferior alveolar nerve (IAN) (e.g. by chiselling) should be avoided to prevent neural damage. A modification of the Obwegeser-Dal Pont operation technique was studied by splitting 100 pig mandibles ex vivo. An additional osteotomy at the caudal border of the mandible was used to facilitate the sagittal split by means of a locus of minor resistance. The chisel was inserted distal to the second molar and far away from the IAN. The mandible was split by torque. The modified technique reduced the required torque to split the mandible about 30% compared with the original technique (paired t-test, t(69)=-12.89; p<0.05). 75% of all mandibles split by the modified technique were classified as bad splits compared with 100% using the original technique using the same protocol without the additional osteotomy.
International Journal of Oral and Maxillofacial Surgery 01/2011; 40(5):516-20. · 1.51 Impact Factor
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M R Kesting,
M Stoeckelhuber,
F Hölzle,
T Mücke,
K Neumann,
K Woermann,
F Jacobsen,
L Steinstraesser, K-D Wolff,
D J Loeffelbein,
N H Rohleder
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ABSTRACT: Increasing numbers of antibiotics have lost efficiency because of bacterial resistance. The consequences can be severe when surgical wounds become infected during postoperative care. Natural peptide antibiotics, the so-called host defence peptides (HDPs), have been investigated since the 1990s in a search for alternative treatment strategies. HDPs build up a protection shield against pathological microorganisms, especially in human epithelium. The use of HDPs is currently being discussed as a new antimicrobial therapeutic strategy. Accordingly, a profound knowledge of the quantitative relationships of the effectors is essential.
To evaluate differences in HDP expression between postoperatively inflamed and healthy epithelium.
Expression profiles of the genes encoding HDP human beta-defensin (hBD)-1 (DEFB1, previously known as HBD-1), hBD-2 (DEFB4A, previously known as HBD-2), hBD-3 (DEFB103A, previously known as HBD-3) and psoriasin (S100A7) were assessed in samples of surgical wound healing disorders (n = 27) and healthy epithelium (n = 16) by using real-time polymerase chain reaction. Immunohistochemical staining was performed in the same samples.
A significant overexpression of DEFB4A (P < 0.001), DEFB103A (P = 0.001) and S100A7 (P < 0.001) was found in cutaneous surgical site infections. Immunohistochemistry revealed intensely elevated protein levels of psoriasin in infected wounds, and differences in distribution with respect to the epithelial layers.
The study demonstrates upregulated mRNA expression and protein levels of HDPs in postoperatively inflamed epithelium. The results may be a starting point for novel pharmacological treatments.
British Journal of Dermatology 03/2010; 163(1):121-7. · 3.67 Impact Factor
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ABSTRACT: The authors present a case of a rare highly malignant condition that initially appeared clinically and histologically to be the relatively common and benign condition necrotizing gingivitis. Conditions that do not follow the expected clinical course mandate further investigation because rare malignant disease is not foremost in the mind of dentists and oral and maxillofacial surgeons.
International Journal of Oral and Maxillofacial Surgery 03/2010; 39(8):827-30. · 1.51 Impact Factor
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Journal of Veterinary Pharmacology and Therapeutics 02/2010; 33(1):100-2. · 1.18 Impact Factor
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ABSTRACT: In transplantation procedures vascular anastomoses are usually sutured. Although there are a lot of problems with suturing
anastomoses no other technique, like gluing or lasering the anastomosis, could be establish in microvascular tissue transplantation.
Therefore a method for anastomosing blood vessels with stents in clinical use of microvascular tissue transplantation has
been developed.
In this work we present a comparative method to determine the tensile strength of a stented microvascular anastomosis. It
was also investigated, how length and dilatation of the developed stent influence tensile strength of the stented anastomosis.
Overall 24 vessels of thiel-fixed human cadavers were investigated, divided into four groups (A: sutured anastomoses; B: 17
mm stent, dilation to ∅ 2.5 mm; C: 23 mm stent, dilation to ∅ 2.5 mm; D: 17 mm stent, dilation to ∅ 4.0 mm). Prior to these
analyses different gripping devices were additionally tested and validated.
The results of our researches showed that sutured anastomoses got the best tensile strength of all tested anastomoses. Dilatated
stented anastomoses (17 mm stents, ∅ 4.0 mm expanded) reached half the tensile strength of the conventional sutured anastomoses.
If the stent is less dilatated, only minor tensile strength of the anastomosis resulted.
Stenting might become an alternative way to perform microvascular anastomoses to suturing and provide safety for the transplanted
tissue especially in lack of surgical experience. Further studies to improve the implanting method and to enhance the grip
between stent and vessel are necessary to develop a clinical useful stent for microvascular anastomosis.
Keywordsanastomosis-stent-microsurgery-tensile strength
01/2010: pages 33-36;
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ABSTRACT: Four free-flap types were compared regarding perioperative blood perfusion parameters and to define critical values for success. 166 cases were investigated: radial forearm flap (fasciocutaneous, n=89); fibula flap (osteocutaneous, n=32); ALT flap (myocutaneous, n=25); soleus perforator flap (n=20). All flaps were monitored with simultaneous laser-Doppler flowmetry and tissue spectrophotometry intra- and postoperatively up to 14 days. In 24 (15%) of 166 cases perfusion irregularity occurred. Operative exploration was performed in 12 cases (9 successful). 11 flaps (5 radial forearm, 3 fibula, 2 ALT, 1 perforator) were lost due to vascular compromise, which led to an overall success rate of 93%. Rapid increase in haemoglobin concentration of >30% identified venous congestion. Abrupt decline of blood flow and haemoglobin oxygenation indicated arterial occlusion. For radial forearm flaps haemoglobin oxygenation of 15% and a deep flow of 20 AU were identified as minimum values for flap viability. For fibula, ALT, and perforator flaps haemoglobin oxygenation of 10% and a deep flow of 15 AU were determined as the minimum values. This non-invasive technique was an accurate method for evaluating viability of free-flaps.
International Journal of Oral and Maxillofacial Surgery 11/2009; 39(1):21-8. · 1.51 Impact Factor
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ABSTRACT: The aim of this study was to investigate the changes in nasal airways after Le Fort I osteotomy and functional rhinosurgery. 49 patients were included in this study to assess intranasal anatomical and functional changes resulting from a Le Fort I osteotomy. The data were classified according to the three-dimensional positioning of the maxilla: in group I the maxilla was impacted; in group II the maxilla was inferior; and in group III only sagittal maxillary movement was performed. Presurgical and 5 months postsurgical rhinological inspection, anterior rhinomanometry and acoustic rhinometry were carried out. Additional rhinosurgery, such as resection of the inferior concha or septoplastic intervention, was performed to avoid functional problems in nasal breathing, particularly when the maxilla was impacted. Rhinomanometric assessment showed a significant improvement in nasal breathing in the whole group and each single group. Acoustic rhinometry revealed an increase in typical cross-sectional intranasal areas. The authors conclude that concerns about the respiratory consequences of this surgical procedure appear unwarranted when functional rhinosurgery is undertaken concomitantly, particularly in patients with increased preoperative nasal airway resistance.
International Journal of Oral and Maxillofacial Surgery 03/2009; 38(4):321-5. · 1.51 Impact Factor
