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Eine bewahrte und haufig angewandte Operation bei Patienten (Pat) mit idiopathischer Skoliose (IS) ist die dorsale transpedikulare Korrekturspondylodese in Freihandtechnik. Neuere Verfahren mit fluoroskopisch- und CT-gestutzter Navigation sind mutmaslich risikoarmer und exakter. Ist die Freihandtechnik bei IS bezuglich der schraubenassoziierten Komplikationen und intraoperativen Strahlenbelastung sicher? Anhand prospektiv erfasster Daten (2017–2018) von 39 konsekutiven Pat (durchschn. Alter 18,7 J.) mit thorakal einbogiger IS (61,7° ±13,9) eines Skoliosezentrums wurden folgende Parameter (Mittelwert ± Standardabweichung) ausgewertet: Gesamtstrahlenprodukt, Durchleuchtungszeit, fusionierte Segmente, Operationszeit, Blutverlust und schraubenassoziierte Komplikation. Es erfolgte ein Literaturvergleich mit Daten zur intraoperativen Strahlenbelastung bei Navigationsverfahren. Das Gesamtstrahlenprodukt/Pat betrug 71,7 ± 44,0 cGy * cm2, die Durchleuchtungszeit 17,4 ± 8,6 s (7,8 Segmente), die Operationszeit 183,5 ± 54,2 min und der Blutverlust 379,5 ± 183 ml. Keine schraubenassoziierte Komplikation im gesamten Kollektiv. Die Korrektur der Hauptkrummung betrug 75,7 %. Der Vergleich der erhobenen Daten mit denen aus der Literatur zeigte eine fur den Pat 1,25- bis 12,5-fach hohere Strahlenexposition bei fluoroskopisch- gestutzter Navigation und 9,25- bis 12,3-fach hohere bei CT-gestutzten Verfahren. Freihandiges Setzen von Pedikelschrauben ist bei entsprechender Erfahrung mit vergleichbarer Genauigkeit und geringerer Strahlenbelastung fur den Pat verbunden als navigierende Verfahren. Hinsichtlich des geringen Alters der Pat sollte ein strahleninduziertes Langzeitrisiko fur maligne Erkrankungen berucksichtigt werden.

Sehr geehrte Leserin, sehr geehrter Leser, der oben genannte Beitrag wurde mit einem fehlerhaften Titel publiziert. Bitte beachten Sie den korrekten Titel und Untertitel: Geringe intraoperative Strahlenbelastung fur Skoliosepatienten. Freihandige Instrumentation mit Vergleich zur Navigation Wir …

In the era of tissue engineering, the physiologic process of skin graft revascularization remains unclear, preventing the successful development of skin substitutes. Therefore, the authors developed a new in vivo model with which to visualize the process of engraftment and its microvascular architecture. The aim of this study was to specifically investigate the vascular transformations within the skin graft to gain applicable knowledge on how vascular processes during engraftment occur.Microsurgical preparation of the modified dorsal skinfold chamber including autologous skin grafting was performed in male C57BL/6J mice (n = 10). In addition, immunohistochemistry of angiogenic factors, endothelial cells, and pericytes, and corrosion casting were performed to further characterize the specific mechanisms.The graft exhibited capillary widening starting at day 3, resulting in the temporary formation of spherical protrusions at the graft capillary divisions starting in the center of the graft 24 to 48 hours after revascularization. Confocal microscopy showed the simultaneous expression of CD31 and desmin. Corrosion casting and evaluation by light microscopy and scanning electron microscopy showed the three-dimensional formation of capillaries in the wound bed that connected to the preexisting capillary loops of the skin graft.The authors were able to show for the first time a temporary angiogenic response within the capillaries of the skin graft. This most likely represents a reaction to reperfusion allowing the supply of proangiogenic factors to the hypoxic skin graft. The detection of an angiogenic response within the graft capillaries is for the first time made possible in the newly developed model and is therefore completely novel.

This study aims to quantify by intravital microscopy and histological wound scoring the effect of radial pressure wave treatment (RPWT) on murine incisional wound healing. The dorsal skinfold chamber in mice was used for intravital microscopy, whereby an incisional wound was created within the chamber. RPWT to the wound was carried out using a ballistic pressure wave source (EMS Swiss DolorClast). Animals received a dose of 500 pulses at an energy flux rate of 0.1mJ/mm(2) and a frequency of 3Hz at day 1, 3, 5, 7, 9, and 11 post wounding. RPW treated and untreated ApoE depleted mice (ApoE(-/-)) were compared to normal healing wild type animals (WT). The microcirculation of the wound was analyzed quantitatively in vivo using epi-illumination intravital fluorescence microscopy. Tissue samples were examined ex vivo for wound scoring and immunohistochemistry. Upon RPWT total wound score in ApoE(-/-) mice was increased by 13% (not significant) on day 3, by 37% on day 7 (P

Cigarette smoking increases the risk for myocardial diseases and is associated with a higher incidence of postoperative complications. Previous studies showed an increased leukocyte rolling and adhesion following nicotine application. Next to this the use of estrogen containing oral contraceptives is linked to a higher risk for deep vein thrombosis. However, clinical studies investigating the influence of transdermal nicotine application on cardiovascular risk factors could not show a negative effect of nicotine. Therefore transdermal nicotine replacement is regarded as a safe aid to smoking cessation. It is still not clear whether nicotine or other substances in cigarette smoke are responsible for the prothrombotic risk associated with cigarette smoking. Aim of this study was therefore to investigate the influence of nicotine on microvascular thrombus formation in vivo and to further characterize the underlying mechanisms. In microvessels of dorsal skin fold chambers of mice, light-dye-induced thrombus formation was analyzed using intravital fluorescence microscopy. Male and female C57BL/ 6J mice received nicotine chronically via the drinking water (100 µg/ml) for 8 weeks. Control animals of both gender received normal drinking water. Subsequently plasma levels of cotinine, a stable metabolite of nicotine, were determined. To study the influence of nicotine on endothelial cell function immunohistochemical tissue sections for the vascular localization of P-selectin, PAI-1, PAF-R and ICAM-1 were performed. Furthermore the plasma concentrations of soluble P-selectin, E-selectin, ICAM-1 and VCAM-1 were quantified by ELISA. To characterize the influence of nicotine on platelet activation, flowcytometric analyses of the expression of P-selectin, GPIIb/IIIa and CD107a on murine platelets were carried out. Chronic nicotine exposition caused cotinine plasma levels similar to those seen in chronic smokers (> 100 ng/ml vs. controls: < 10 ng/ml). In male animals no significant differences in microvascular thrombus formation were detected following chronic nicotine application, when compared to controls (complete arteriolar and venular occlusion: 640 ± 96 s and 427 ± 51 s vs. control: 577 ± 78 s and 531 ± 102 s). Likewise in female animals no significant differences were found, following long-term nicotine application (complete arteriolar and venular occlusion: 715 ± 130 s and 493 ± 79 s vs. control: 866 ± 24 s and 481 ± 70 s). In line with this, flow cytometric analyses did not show significant effects of nicotine on P-selectin, GPIIb/IIIa and CD107a expression on resting platelets or upon stimulation with thrombin (20 U/ml). In contrast to this chronic nicotine application caused a marked reduction of vascular expression of P-selectin, PAF-R and PAI-1 in male mice, while in female mice only PAI-1 was found significantly reduced. Additionally chronic nicotine treatment lead to a significant reduction of sP-selectin and sE-selectin circulation in male mice. The present study shows no significant influence of chronic nicotine treatment on microvascular thrombus formation and platelet adhesion molecule expression despite elevated cotinine levels in mice of both gender. However, chronic nicotine treatment resulted in a significant reduction of endothelial adhesion molecule expression in male mice, while there was only a slight effect in female mice.