Untersuchung zur Anwendbarkeit der Argon-Plasma-Koagulation (APC) in einem Modellversuch für neurochirurgische Operationen

Die Argon-Plasma-Koagulation (APC) wird heutzutage in vielen chirurgischen Disziplinen und deren operativen Indikationen angewendet. In der Neurochirurgie wurde jedoch bisher von einer Anwendung abgesehen, da die Datenlage zur Reaktion des Nervengewebes auf diese Art der monopolaren Koagulation noch unklar ist. Für die genaue Evaluation der Art und Ausdehnung des Gewebeschadens wurde ein Tiermodell mit einem standardisierten Versuchsaufbau etabliert, um die Auswirkungen von Helium(Argon)-Plasma-Koagulation auf das Rattenhirn zu untersuchen. Die Gewebereaktionen wurden mit konventionellen und immunhistologischen Färbemethoden dokumentiert und untersucht. Weiterhin wurde ein zeitabhängiges Profil der Umbauprozesse erstellt, welches sich über eine bis sechs Wochen nach der Operation erstreckte. Die Gewebsreaktion stellte sich als eine Abgrenzung von klar demarkierten konzentrischen Zonen dar. Die Organisation des Gewebeschadens fand sowohl an den Rändern als auch im Zentrum der Läsion statt. Die Schichten der Läsion nehmen durch unterschiedliche Mechanismen an der Reparatur des Gewebeschadens teil; die weitere Beobachtung dieser Schichten kann daher zum besseren Verständnis der Organisationsvorgänge führen. Diese Studie hat gezeigt, dass man durch H(A)PC eine scharf abgrenzbare und reproduzierbare Läsion an Rattenhirngewebe generieren kann. Die Methode erwies sich wie in anderen chirurgischen Indikationen als minimal traumatisch. Daher ist die klinische Anwendung dieser Methode vielversprechend. Außerdem sind die H(A)PC-Läsionen sehr gut geeignet, um die Morphologie früher und später reparativer Reaktionen neuronaler Gewebe zu studieren

Untersuchung zur Anwendbarkeit der Argon-Plasma-Koagulation (APC) in einem Modellversuch für neurochirurgische Operationen

Die Argon-Plasma-Koagulation (APC) wird heutzutage in vielen chirurgischen Disziplinen und deren operativen Indikationen angewendet. In der Neurochirurgie wurde jedoch bisher von einer Anwendung abgesehen, da die Datenlage zur Reaktion des Nervengewebes auf diese Art der monopolaren Koagulation noch unklar ist. Für die genaue Evaluation der Art und Ausdehnung des Gewebeschadens wurde ein Tiermodell mit einem standardisierten Versuchsaufbau etabliert, um die Auswirkungen von Helium(Argon)-Plasma-Koagulation auf das Rattenhirn zu untersuchen. Die Gewebereaktionen wurden mit konventionellen und immunhistologischen Färbemethoden dokumentiert und untersucht. Weiterhin wurde ein zeitabhängiges Profil der Umbauprozesse erstellt, welches sich über eine bis sechs Wochen nach der Operation erstreckte. Die Gewebsreaktion stellte sich als eine Abgrenzung von klar demarkierten konzentrischen Zonen dar. Die Organisation des Gewebeschadens fand sowohl an den Rändern als auch im Zentrum der Läsion statt. Die Schichten der Läsion nehmen durch unterschiedliche Mechanismen an der Reparatur des Gewebeschadens teil; die weitere Beobachtung dieser Schichten kann daher zum besseren Verständnis der Organisationsvorgänge führen. Diese Studie hat gezeigt, dass man durch H(A)PC eine scharf abgrenzbare und reproduzierbare Läsion an Rattenhirngewebe generieren kann. Die Methode erwies sich wie in anderen chirurgischen Indikationen als minimal traumatisch. Daher ist die klinische Anwendung dieser Methode vielversprechend. Außerdem sind die H(A)PC-Läsionen sehr gut geeignet, um die Morphologie früher und später reparativer Reaktionen neuronaler Gewebe zu studieren

Do-It-Yourself Preoperative High-Resolution Ultrasound-Guided Flap Design of the Superficial Circumflex Iliac Artery Perforator Flap (SCIP)

The superficial circumflex iliac artery perforator (SCIP) flap is a well-documented, thin, free tissue flap with a minimal donor site morbidity, and has the potential to become the new method for resurfacing moderate-size skin defects. The aim of this study is to describe an easy, reliable, systematic, and standardized approach for preoperative SCIP flap design and perforator characterization, using color-coded duplex sonography (CCDS). A list of customized settings and a straightforward algorithm are presented, which are easily applied by an operator with minimal experience. Specific settings for SCIP flap perforator evaluation were investigated and tested on 12 patients. Deep and superficial superficial circumflex iliac artery (SCIA) branches, along with their corresponding perforators and cutaneous veins, were marked individually with a permanent marker and the anatomy was verified intraoperatively. From this, a simplified procedure for preoperative flap design of the SCIP flap was developed. Branches could be localized and evaluated in all patients. A preoperative structured procedure for ultrasonically guided flap design of the SCIP flap is described. A 100% correlation between the number and emergence points of the branches detected by preoperative CCDS mapping and the intraoperative anatomy was found

Using High-Resolution Ultrasound to Assess Post-Facial Paralysis Synkinesis—Machine Settings and Technical Aspects for Facial Surgeons

Background: Synkinesis of the facial musculature is a detrimental sequalae in post-paralytic facial palsy (PPFP) patients. Detailed knowledge on the technical requirements and device properties in a high-resolution ultrasound (HRUS) examination is mandatory for a reliable facial muscle assessment in PPFP patients. We therefore aimed to outline the key steps in a HRUS examination and extract an optimized workflow schema. Methods: From December 2020 to April 2021, 20 patients with unilateral synkinesis underwent HRUS. All HRUS examinations were performed by the first author using US devices with linear multifrequency transducers of 4–18 MHz, including a LOGIQ E9 and a LOGIQ S7 XDclear (GE Healthcare; Milwaukee, WI, USA), as well as Philips Affinity 50G (Philips Health Systems; Eindhoven, the Netherlands). Results: Higher-frequency and multifrequency linear probes ≥15 MHz provided superior imaging qualities. The selection of the preset program Small Parts, Breast or Thyroid was linked with a more detailed contrast of the imaging morphology of facial tissue layers. Frequency (Frq) = 15 MHz, Gain (Gn) = 25–35 db, Depth (D) = 1–1.5 cm, and Focus (F) = 0.5 cm enhanced the image quality and assessability. Conclusions: An optimized HRUS examination protocol for quantitative and qualitative facial muscle assessments was proposed

Feasibility study of preoperative microvessel evaluation and characterization in perforator flaps using various modes of color-coded duplex sonography (CCDS)

Background Color-coded duplex sonography (CCDS) is useful for perforator flap design showing the highest sensitivity in identifying microvessels. This prospective study evaluates the feasibility of different ultrasound (US) modes applied by the microsurgeon in daily practice suggesting quantifiable reference values. Methods Twenty-four patients aged between 17 and 68 years (mean 43.3 +/- 14.2 years) with 18 anterolateral thigh (ALT) and 6 superficial circumflex iliac artery (SCIP) flaps were included. Indications were traumatic (n= 12), infectious (n= 6), ischemic (n= 4), or tumor-associated defects (n= 2). Different US modes were evaluated regarding applicability using multifrequency linear probes (5-15 MHz). Vessels diameter, peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were measured. Preoperative results were correlated to intraoperative findings. Results In the examined patient group with 24 perforator flaps a 100% correlation was seen when comparing perforators detected with CCDS/PD with intraoperative findings using optimized US settings. Sensitivity, PPV, and accuracy of CCDS were 100% respectively. Mean PSV of 16.99 +/- 6.07 cm/s, mean EDV of 5.01 +/- 1.84 cm/s and RI of 0.7 +/- 0.07 were measured in microvessels (PW-mode). CCDS proved to be superior compared to PD in correct diameter assessment showing a mean diameter of 1.65 +/- 0.45 mm, compared to PD-mode 1.31 +/- 0.24 mm. Mean PSV and EDV were higher in ALT than in SCIP flaps, RI was slightly higher in SCIP flaps (p > .05). There were no significant differences in size of different flaps' perforators (p > .05). Conclusion CCDS represents a highly valuable tool in the daily practice of free flap reconstructions using optimized low flow US settings and multifrequency linear probes

Protein kinase activity of phosphoinositide 3-kinase regulates cytokine-dependent cell survival

Extent: 14 p.The dual specificity protein/lipid kinase, phosphoinositide 3-kinase (PI3K), promotes growth factor-mediated cell survival and is frequently deregulated in cancer. However, in contrast to canonical lipid-kinase functions, the role of PI3K protein kinase activity in regulating cell survival is unknown. We have employed a novel approach to purify and pharmacologically profile protein kinases from primary human acute myeloid leukemia (AML) cells that phosphorylate serine residues in the cytoplasmic portion of cytokine receptors to promote hemopoietic cell survival. We have isolated a kinase activity that is able to directly phosphorylate Ser585 in the cytoplasmic domain of the interleukin 3 (IL-3) and granulocyte macrophage colony stimulating factor (GM-CSF) receptors and shown it to be PI3K. Physiological concentrations of cytokine in the picomolar range were sufficient for activating the protein kinase activity of PI3K leading to Ser585 phosphorylation and hemopoietic cell survival but did not activate PI3K lipid kinase signaling or promote proliferation. Blockade of PI3K lipid signaling by expression of the pleckstrin homology of Akt1 had no significant impact on the ability of picomolar concentrations of cytokine to promote hemopoietic cell survival. Furthermore, inducible expression of a mutant form of PI3K that is defective in lipid kinase activity but retains protein kinase activity was able to promote Ser585 phosphorylation and hemopoietic cell survival in the absence of cytokine. Blockade of p110α by RNA interference or multiple independent PI3K inhibitors not only blocked Ser585 phosphorylation in cytokine-dependent cells and primary human AML blasts, but also resulted in a block in survival signaling and cell death. Our findings demonstrate a new role for the protein kinase activity of PI3K in phosphorylating the cytoplasmic tail of the GM-CSF and IL-3 receptors to selectively regulate cell survival highlighting the importance of targeting such pathways in cancer.Daniel Thomas, Jason A. Powell, Benjamin D. Green, Emma F. Barry, Yuefang Ma, Joanna Woodcock, Stephen Fitter, Andrew C.W. Zannettino, Stuart M. Pitson, Timothy P. Hughes, Angel F. Lopez, Peter R. Shepherd, Andrew H. Wei, Paul G. Ekert and Mark A. Guthridg

Complications following orthognathic surgery for patients with cleft lip/palate: A systematic review

The purpose of this systematic review is to update the available data for complications following orthognathic surgery in cleft lip and/or palate patients. Methods: Three electronic databases (Medline, Embase, and Cochrane) were searched for publications from 1990 to 2014. Results: A total of 26 articles were selected including 1003 patients (male: 391, female: 353, 259: not mentioned) who underwent maxillary osteotomies for cleft lip/palate. Mean age at surgery was 19.3 years (range: 8.5–60 years). Overall perioperative complications were reported in 126 cases (12.76%). The most common complication was closure failure of pre-existing palatal fistula (28.57%), followed by velopharyngeal impairment (16.79%), closure failure of pre-existing alveolar fistula (10.74%), gingival recession (4.55%), and failure of premaxilla stabilization in bilateral cases (4.55%). Severe vascular complications included one arteriovenous fistula (0.10%), one maxillary aneurysm (0.10%), and one cavernous sinus thrombosis (0.10%). Mean horizontal relapse rate was 17.9% (range: −20.0% to 37.2%), and mean vertical relapse rate was 35.4% (range: −25.9% to 162.5%). Reoperation rate was 12.2% (range: 0.0–64.0%). Prospective studies or randomized trials were rare. Conclusion: To obtain a dataset with higher evidence, a prospective multicenter study should be conducted with clearly defined criteria for each complication

3D printing in orthognathic surgery − A literature review

With the recent advances in three-dimensional (3D) imaging, computer-assisted surgical planning and simulation are now regularly used for analysis of craniofacial structures and improved prediction of surgical outcomes in orthognathic surgery. A variety of patient-specific surgical guides and devices have been designed and manufactured using 3D printing technology, which rapidly gained widespread popularity to improve the outcomes. The article presents an overview of 3D printing technology for state-of-the-art application in orthognathic surgery and discusses the impacts on treatment feasibility and patient outcome. The current available literature regarding the use of 3D printing methods in orthognathic surgery including 3D computer-aided design/computer-aided manufacturing, rapid prototyping, additive manufacturing, 3D printing, 3D printed models, surgical occlusal splints, custom-made guides, templates and fixation plates is reviewed. A Medline, PubMed, ProQuest and ScienceDirect search was performed to find relevant articles over the past 10 years. A total of 318 articles were found, out of which 69 were publications addressing the topic of this study. An additional 9 hand-searched articles were added. From the review, we can conclude that the use of 3D printing methods in orthognathic surgery provide the benefit of optimal functional and aesthetic results, patient satisfaction, and precise translation of the treatment plan. Keywords: Orthognathic surgery, 3D printing, Computer-aided design, Computer-aided manufacturing, Rapid prototyping, Additive manufacturin

An integrated surgical protocol for adult patients with hemifacial microsomia: Methods and outcome

<div><p>Background</p><p>Hemifacial microsomia (HFM) features hypoplasia and asymmetry in skeletal as well as soft tissue, and correction of the deformity is difficult in terms of aesthetic outcome. The purpose of this study is to examine the validity of an integrated treatment protocol for correction of this facial deformity.</p><p>Patients and methods</p><p>A retrospective study was performed on adult HFM patients who received two-jaw orthognathic surgery combined with facial contouring procedures in the first stage, and fat injection for the residual facial deficiency in the second stage. Inclusion criteria were patients treated by the same surgeon and follow-up at least 6 months. The demographic, perioperative, and follow-up data were collected. We defined a facial surface area discrepancy index (FDI) for objective assessment of the symmetry between the affected and non-affected side, and utilized visual analogue scale (VAS) for subjective evaluation of facial asymmetry before and after surgical treatment.</p><p>Results</p><p>A total of 14 patients were included. The mean age at orthognathic surgery was 21.7 years. Four patients were categorized as Pruzansky-Kaban type I, while the remaining 10 patients were type II (7 patients type IIA, 3 patients type IIB). Fat injection as a secondary procedure was performed in eleven cases (79%). The mean pre- and postoperative FDI was 87.6±6.3 and 95.4±5.2 with a significant advance for symmetry (<i>p <</i> 0.001). The pre- and postoperative VAS for asymmetry was 7.2±1.7 and 3.8±2.4 respectively, with a significant improvement (<i>p</i> = 0.002).</p><p>Conclusion</p><p>Our integrated approach using orthognathic surgery, facial contouring surgery and subsequent fat injection is satisfactory and obtain significant improvement of the facial deformity considering the complexity of HFM.</p></div