[Integrity of swallowing apparatus-past, present, and future]. / Integrität der Schluckstraße ­ gestern, heute, morgen.

BACKGROUND: Swallowing is one of the most complex movement patterns. The integrity of the epithelial lining is essential. OBJECTIVE: Which surgical techniques were developed at the beginnings of modern surgery and what methods are now available to maintain/reconstitute the integrity of the swallowing apparatus? MATERIALS AND METHODS: This study comprises a selective literature search in early operation manuals and online archives, with incorporation of the authors' own experience. RESULTS: Up until the 1950s, only very limited techniques were available to reconstruct the epithelial lining. Microvascular reanastomosed grafts were the game changer for reconstructive surgery, enabling reconstitution of the swallowing apparatus in primary surgery but also in challenging secondary interventions after insufficient or complicated primary therapy. CONCLUSION: The need for anatomical and functional rehabilitation by reconstructive surgery is as pertinent as ever. Particularly in the oncological context, improved early detection and novel local treatment modalities could minimize treatment-associated damage to swallowing.

[Early recognition of cancerous lesions in the mouth and oropharynx: Automated evaluation of hyperspectral image stacks]. / Früherkennung kanzeröser Läsionen in Oropharynx und Mundhöhle: Automatisierte Evaluation hyperspektraler Bildstapel.

BACKGROUND: Early detection of cancerous lesions is still crucial for a patient's prognosis. Although diagnostic access to the oral cavity and oropharynx is comparably easy, the incidence of resulting disease remains high. This is due to the fact that in many cases, malignity is recognized too late on a purely visual basis. Previously, we discussed the application of hyperspectral imaging for early detection of precancerous and cancerous lesions of the larynx. This time, we evaluate the method in the oral cavity and oropharynx. MATERIALS AND METHODS: In 85 patients scheduled for endoscopy, hyperspectral imaging was performed. We used a rigid 0-degree endoscope, a light-adjustable monochromator, and a hyperspectral camera. For evaluation of the method, 3 patients were chosen exemplarily. Training sites from physiological and cancerous tissues were marked. Hyperspectral data from 1 patient were used to train a classifier, which was then used for automatic detection of precancerous and cancerous lesions in another 2 patients. RESULTS: Intraoperative hyperspectral imaging was performed without any problems. Classification showed sensitivities of 61 and 43%, and a specificity of 100%. CONCLUSION: This proof-of-concept study underscores the high potential of hyperspectral imaging for early recognition of cancer in the mouth and oropharynx. Besides a better prognosis for cancer patients, this approach could lead to higher cost efficiency in the health system.

[Evaluation and Optimization of Microvascular Arterial Anastomoses by Transit Time Flow Measurement]. / Evaluation und Optimierung arterieller Anastomosen durch Transit-Zeit Flussvolumenmessungen.

UNLABELLED: INDRODUCTION: The regular application of transit time flow measurement in microvascular anastomoses during heart surgery has lead to improvements of the outcome of coronary artery bypass grafts. Our study was meant to discover whether this measurement method was also applicable for evaluation and optimization of microvascular arterial anastomoses of radial forearm flaps. METHODS: In this prospective examination a combining ultrasound imaging and transit time flow measurement device (VeriQ, MediStim) was used during surgery to assess anastomotic quality of 15 radial forearm flaps. Pulsatility index (PI) and mean blood flow were measured immediately after opening the arterial anastomosis as well as 15 min afterwards. Furthermore, application time and description of handling were recorded seperately for every assessment. RESULTS: Mean blood flow immediately after opening the anastomosis and 15 min later were 3.9 and 3.4 ml/min resepectively showing no statistically significant difference (p=0.96). There was no significance in the increase of pulsatility index from 22.1 to 27.2 (p=0.09) during the same time range, either. Due to measurement results showing atypical pulse curves in 2 cases decision for surgical revision of the anastomoses was made. All forearm flaps showed good vascularisation during follow-up. Time for device set up, probe placement and measurements was about 20 min. Handling was described to be uncomplicated without exception. There were no noteworthy problems. CONCLUSION: Transit time flow measurement contributes to the improvement of anastomotic quality and therefore to the overall outcome of radial forearm flaps. The examined measurement method provides objective results and is useful for documentation purposes.

[Soft tissue tumors of the head and neck region]. / Weichteiltumoren des Kopf-Hals-Bereichs.

BACKGROUND: The incidence of soft tissue tumors of the head and neck region is low: 300 and 3 in 100,000 for benign and malignant tumors, respectively. However, sarcomas particularly show a wide variety of different histological subtypes. This article provides an overview of the soft tissue tumors of the head and neck region treated in the authors' institution. MATERIAL AND METHODS: This is a retrospective study including 106 patients treated between 2002 and 2010 due to a soft tissue tumor. Tumor- and patient-specific data were collected (benign/malignant tumor, location, TNM classification, therapy, R classification, grade). RESULTS: In total, 77 benign tumors, 5 of intermediate benign/malignant nature and 24 sarcomas (with 7 different subtypes) were identified. Whereas the benign and intermediate tumors were treated by surgical removal, in 21 of the 24 sarcomas, treatment comprised a multimodal therapy regimen including radio- and/or chemotherapy. CONCLUSION: Whereas benign tumors can be successfully treated by surgical resection, there is no uniform therapy regimen for sarcomas due to the variety of different histological subtypes. Only case-specific interdisciplinary disease management can offer good perspectives for therapeutic success.

[Hyperspectral imaging in head & neck oncology]. / Hyperspectral Imaging in der Kopf-Hals-Onkologie.

Hyperspectral Imaging has long been established in other scientific disciplines than medicine (e. g. earth science) as a means for objective classification of image data information. Some 10 years ago it was first introduced into medicine. Due to its immanent advantages - non-destructive specimen, compatibility with established optical tools (microscope, endoscope), objectivity, and user-independence - several attempts have been made in order to use its potential for the treatment of cancer patients. This publication reviews which methods have been developed for analogue issues in disciplines other than medicine, how these can be transferred into medicine, and what the perspectives are for the traditional innovative field of head-and-neck-oncology.

[Endoscopy of the larynx by hyperspectral imaging]. / Endoskopie des Larynx mit Hyperspectral Imaging.

BACKGROUND: Hyperspectral imaging has been proven to be useful in remote earth sensing, e.g., satellite-based classification of vegetation. After modifying it for in vivo evaluation of the larynx using microscopy, we show its adoption for endoscopes. MATERIALS AND METHODS: In addition to routine microlaryngoscopies under white light inspection, the laryngoscopy was also performed with not only a conventional operation microscope mounted with a tuneable monochromatic light source and a synchronously triggered monochromatic CCD camera (n = 47 patients), but also a similarly modified rigid 0° endoscope (n = 16 patients). Hyperspectral image cubes were obtained between 390 and 680 nm, analyzed using established software tools, and the data using microscope versus endoscope were compared. RESULTS: Under endoscopy, illumination was more even and sterical resolution appeared unchanged at significantly shorter image acquisition times. Hyperspectral classification delineated areas of altered mucosa without further external information irrespective of whether image cubes were generated with microscopy or endoscopy. CONCLUSION: Hyperspectral imaging can be transferred not only to micro(laryngo)scopy but also to endoscopy with rigid optics. This opens the way to a variety of clinically relevant anatomical regions (e.g., upper aerodigestive tract). Its adoption to flexible optics will further broaden this spectrum.

[Cytomics and predictive medicine for oncology]. / Zytomik und prädiktive Medizin in der Onkologie.

One hundred and fifty years after Virchow introduced his fundamental concept of cellular pathology, we now have tools that allow us to unravel the mechanisms of single living cells on a previously unprecedented level of detail. By exploring the molecular cellular phenotype, multiparametric cytometry not only detects specific cellular functions in general but also offers insights into the interaction of single subunits of proteins (e.g., growth factor receptors). Several quantitative and objective techniques allow analysis of single-cell preparations as well as tissue sections to obtain data on different cellular parameters. This opens the way to quantitative and objective histology, which in the future may be possible even without blood or the need to make an incision. To use this huge amount of data for treatment decisions in an individual patient, novel bioinformatic concepts are needed in order to predict the individual course of a disease. The concept of cytomics centers on the cell as the integral unit of all life and explores diseases starting from the cell and going to subcellular units (top-down analysis).

Immunophenotyping of peripheral blood leukocytes by laser scanning cytometry.

Many clinical situations demand repeated analyses of blood parameters but permit only minimal amounts of peripheral blood to be taken, e.g., in neonates with low birth weight, during extensive operations of young children, or in patients with restricted bone marrow function. In these cases laser scanning cytometry is the ideal tool to determine the distribution of different leukocyte-subsets. The purpose of this protocol is to describe stepwise a new method of immunophenotyping by laser scanning cytometry. In this assay nuclear DNA is stained by 7-aminoactinomycin-D (7-AAD) and surface antigens are detected by direct three-colour immunofluorescence. For data acquisition, measurements are triggered on the 7-AAD-fluorescence. Data are obtained for forward scatter, green, orange, and long red fluorescence by excitation with the argon-laser, and for far red fluorescence by excitation with the helium-neon-laser. Using this protocol the amount of peripheral blood needed is minimised to 10 microl. Specimens can be stained a second time in a different way and analysed repeatedly and archived.

Analysis of minimal sample volumes from head and neck cancer by laser scanning cytometry.

BACKGROUND: The increasing diversity in therapeutic strategies in head and neck oncology is dependent on the development of equally appropriate diagnostic tools. A growing number of diagnostic procedures is intended to be performed on an out-patient basis. In this context, analyses of hypocellular specimens such as fine-needle aspirate biopsies (FNABs) or swabs are very important: There are minimal side-effects, and they can be analysed within hours. MATERIAL AND METHODS: Laser scanning microscopy (LSC) is a microscope-based method combining the advantages of flow cytometry and image analysis: In addition to the fluorescence data of each individual cell, its morphology can be documented by re-staining with a conventional cytological staining. Any cell can then be re-localised in the microscope for direct observation. FNABs and swabs are incubated in PBS, erythrocytes are lysed, and cells are mounted on slides. After fixation in ethanol, cells are stained for cytokeratin by indirect immunolabelling and for DNA by propidium iodide. Analysis by LSC is performed to determine the ploidy of the epithelial cells. For immunophenotyping of peripheral blood in cancer patients by LSC 20 microl full blood are stained for CD antigens by direct immunolabelling and for DNA by 7-aminoactinomycin D. RESULTS: FNABs and swabs were taken from 150 malignancies of different sites in total; all specimens yielded sufficient cells (>5,000). 30 tumours of the parotid gland were analysed in detail: Out of 9 malignant tumours 8 showed aneuploidy, whereas all 21 benign tumours were diploid. Immunophenotyping in 23 tumour patients showed a significant reduction of lymphocytes in the peripheral blood as compared to healthy individuals. CONCLUSIONS: Further studies have to be performed to validate the analysis of hypocellular specimens by LSC and to determine its role in routine clinical work. Its potential is most evident in tumours that are not accessible for open biopsy such as those of the parotid gland or the larynx.