Assessing long-term, vestibulotoxic side effects after gentamicin therapy in neonatal sepsis or infection using video head impulse test

Study background

Newborn infection and sepsis remain serious problems. Guideline-compliant therapy includes, among other therapeutics, calculated intravenous antibiosis with gentamicin. One of the known side effects of gentamicin is severe vestibulotoxicity, which can be detected using the video head impulse test (VHIT), which is a sensitive examination method for the detection of vestibular hypofunction in children and adults. Previous studies on the vestibulotoxicity of gentamicin in newborns were carried out using caloric testing, rotary testing, and electronystagmography. Nevertheless, there are currently no data available on VHIT examinations in children who have been treated with neonatal gentamicin therapy.

Methods

A single-center, prospective cross-sectional study, was conducted at a tertial referral center. VHIT was performed on 23 children aged 3-7 years who had received intravenous gentamicin therapy for at least five days as part of the treatment of newborn sepsis between 2012 and 2016. Main outcome was median gain and occurrence of refixational saccades as measured with VHIT. In addition, the children's parents received questionnaires to detect possible risk factors and vestibular and cochlear abnormalities.

Results

Out of 23 children with a mean age of four years and seven months (ranging from 3 to 7 years), 11 (47.8%) indicated abnormal results in VHIT. The VHIT results were unilaterally abnormal in six children (26.1%) and bilaterally abnormal in five others (21.7%). Additionally, five of the children with an abnormal HIT had abnormalities, as found in the questionnaire results.

Conclusion

and Relevance: Almost half of the children observed after having undergone gentamicin therapy as newborns showed abnormalities in VHIT, although they did not show any clinical signs of disbalance or vestibular hypofunction. VHIT can serve as a sensitive investigation method for the early screening of post-therapeutic vestibulotoxic side effects after gentamicin therapy in children. Additionally, VHIT can enable early intervention in these children.

Risk factors for immune-related adverse effects during CPI therapy in patients with head and neck malignancies - a single center study

Introduction

Checkpoint inhibitors, such as PD1 inhibitors, represent an important pillar in the therapy of advanced malignancies of the head and neck region. The most relevant complications are immune-related adverse effects (irAEs), which represent an immense burden for patients. Currently, no sufficient stratification measures are available to identify patients at increased risk of irAEs. The aim of this retrospective study was to examine whether demographic, histopathological, clinical, or laboratory values at the start of CPI therapy represent a risk factor for the later occurrence of autoimmune complications.

Material and methods

Data from 35 patients between 2018 and 2021 who received therapy with nivolumab or pembrolizumab for head and neck malignancy were analyzed and assessed for any associations with the subsequent occurrence of irAEs.

Results

IrAE developed in 37% of patients, with pneumonitis being the most common form (14%). Pneumonitis was found in patients with an average significantly lower T-stage of primary tumors. An increase in basophilic leukocytes was found in patients with dermatitis later in the course. When thyroiditis developed later, the patients had a higher CPS score and lower monocyte levels.

Discussion

Even though individual laboratory values at the beginning of therapy might show a statistical association with the later occurrence of irAEs, neither demographic, histopathological, nor laboratory chemistry values seem to be able to generate a sound and reliable risk profile for this type of complication. Therefore, patients need to be educated and sensitized to irAEs, and regular screening for irAEs should be carried out.

[Development and evaluation of ultrasound navigation for free-hand biopsies of small masses in the head and neck area]

BACKGROUND

Ultrasound is an important imaging method in the head and neck area. It is readily available, dynamic, inexpensive, and does not involve radiation exposure. Interventions in the complex head and neck anatomy require good orientation, which is supported by navigation systems.

OBJECTIVE

This work aimed to develop a new ultrasound-controlled navigation system for taking biopsies of small target structures in the head and neck region.

METHODS

A neck phantom with sonographically detectable masses (size: 8-10 mm) was constructed. These were automatically segmented using a ResNet-50-based deep neural network. The ultrasound scanner was equipped with an individually manufactured tracking tool.

RESULTS

The positions of the ultrasound device, the masses, and a puncture needle were recorded in the world coordinate system. In 8 out of 10 cases, an 8‑mm mass was hit. In a special evaluation phantom, the average deviation was calculated to be 2.5 mm. The tracked biopsy needle is aligned and navigated to the masses by auditory feedback.

CONCLUSION

Outstanding advantages compared to conventional navigation systems include renunciation of preoperative tomographic imaging, automatic three-dimensional real-time registration that considers intraoperative tissue displacements, maintenance of the surgeon's optical axis at the surgical site without having to look at a navigation monitor, and working freely with both hands without holding the ultrasound scanner during biopsy taking. The described functional model can also be used in open head and neck surgery.

Rare Case of Tularemia With Preauricular Lymphadenopathy and Conjunctivitis in a 27-Year-Old Male Patient in Germany

Tularemia is a rare disease but shows an approximately 10-fold increase in reported cases over the last 15 years in Germany. Clinical symptoms of acute tularemia infection are various, which often delays diagnosis. This case report gives an overview of the clinical manifestations of acute tularemia and shows the importance of interdisciplinary work to shorten the time from the onset of symptoms to effective treatment in infection with Francisella tularensis. Since some cases of tularemia are life-threatening, early diagnosis is vital. This case report serves as a reminder that rare diseases need to be considered in cervical lymphadenopathy.

Suitability of Ex Vivo-Expanded Microtic Perichondrocytes for Auricular Reconstruction

Tissue engineering (TE) techniques offer solutions for tissue regeneration but require large quantities of cells. For microtia patients, TE methods represent a unique opportunity for therapies with low donor-site morbidity and reliance on the surgeon's individual expertise. Microtia-derived chondrocytes and perichondrocytes are considered a valuable cell source for autologous reconstruction of the pinna. The aim of this study was to investigate the suitability of perichondrocytes from microtia patients for autologous reconstruction in comparison to healthy perichondrocytes and microtia chondrocytes. Perichondrocytes were isolated via two different methods: explant culture and enzymatic digestion. The isolated cells were analyzed in vitro for their chondrogenic cell properties. We examined migration activity, colony-forming ability, expression of mesenchymal stem cell markers, and gene expression profile. We found that microtic perichondrocytes exhibit similar chondrogenic properties compared to chondrocytes in vitro. We investigated the behavior in three-dimensional cell cultures (spheroids and scaffold-based 3D cell cultures) and assessed the expression of cartilage-specific proteins via immunohistochemistry, e.g., collagen II, which was detected in all samples. Our results show that perichondrocytes from microtia patients are comparable to healthy perichondrocytes and chondrocytes in terms of chondrogenic cell properties and could therefore be a promising cell source for auricular reconstruction.

Optimization of extracellular vesicles preparation from saliva of head and neck cancer patients

Small extracellular vesicles from saliva (SEVs) have high potential as biomarkers in Head and Neck cancer (HNC). However, there is no common consensus on the ideal method for their isolation. This study compared different ultracentrifugation (UC) methods (durations and + /- additional purification) with size exclusion chromatography (SEC) and investigated the potential of SEVs as diagnostic biomarkers and their biological activity on NK and CD8+ T cells. SEVs from 19 HNC patients and 8 healthy donors (HDs) were thoroughly characterized. Transmission electron microscopy confirmed the isolation of vesicles by all methods. The average size determined via nanoparticle-tracking analysis was smaller for SEVs isolated by SEC than UC. The highest particle-to-protein yield was achieved by UC (3 h + 3 h) (UCopt) and SEC. However, SEC yielded considerably fewer SEVs. Comparing the surface marker cargo, SEVs isolated by UCopt from HNC patients carried more PD-L1, FasL, and TGF-β than SEVs from HDs. These levels correlated with tumor stage and HPV status. SEVs downregulated NKG2D expression on primary NK cells. HNC SEVs accelerated CD8+ T cell death compared to HD SEVs. This study suggests that UCopt is preferable when isolation of a high particle-to-protein load is required. Especially PD-L1 and FasL on SEVs hold substantial potential as diagnostic biomarkers.

Point Cloud Registration for Measuring Shape Dependence of Soft Tissue Deformation by Digital Twins in Head and Neck Surgery

Introduction

A 2½ D point cloud registration method was developed to generate digital twins of different tissue shapes and resection cavities by applying a machine learning (ML) approach. This demonstrates the feasibility of quantifying soft tissue shifts.

Methods

An ML model was trained using simulated surface scan data obtained from tumor resections in a pig head cadaver model. It hereby uses 438 2½ D scans of the tissue surface. Tissue shift was induced by a temperature change from 7.91 ± 4.1°C to 36.37 ± 1.28°C.

Results

Digital twins were generated from various branched and compact resection cavities (RCs) and cut tissues (CT). A temperature increase induced a tissue shift with a significant volume increase of 6 mL and 2 mL in branched and compact RCs, respectively (p = 0.0443; 0.0157). The volumes of branched and compact CT were decreased by 3 and 4 mL (p < 0.001). In the warm state, RC and CT no longer fit together because of the significant tissue deformation. Although not significant, the compact RC showed a greater tissue deformation of 1 μL than the branched RC with 0.5 μL induced by the temperature change (p = 0.7874). The branched and compact CT forms responded almost equally to changes in temperature (p = 0.1461).

Conclusions

The simulation experiment of induced soft tissue deformation using digital twins based on 2½ D point cloud models proved that our method helps to quantify shape-dependent tissue shifts.

[Hypoglossal Stimulation: Indication, Surgical Technique and Clinical Results]

Hypoglossal stimulation is a safe and effective treatment option for patients with obstructive sleep apnea and unsuccessful PAP therapy. A number of criteria must be met for the indication: proof of failed PAP therapy and ineffectiveness of the other therapy alternatives, AHI of 15-65/h (a relevant number of central and/or mixed apneas should be excluded) and BMI up to max. 35kg/m2. In the case of the respiratory-synchronous and bilateral stimulation system, a complete concentric collapse at the velum level should currently be ruled out in DISE. In the future, stimulation of the branch of the ansa cervicalis innervating the sternothyroid muscle and the ramus internus of the superior laryngeal nerve could open up additional treatment options.

Characterization of Distinct Chondrogenic Cell Populations of Patients Suffering from Microtia Using Single-Cell Micro-Raman Spectroscopy

Microtia is a congenital condition of abnormal development of the outer ear. Tissue engineering of the ear is an alternative treatment option for microtia patients. However, for this approach, the identification of high regenerative cartilage progenitor cells is of vital importance. Raman analysis provides a novel, non-invasive, label-free diagnostic tool to detect distinctive biochemical features of single cells or tissues. Using micro-Raman spectroscopy, we were able to distinguish and characterize the particular molecular fingerprints of differentiated chondrocytes and perichondrocytes and their respective progenitors isolated from healthy individuals and microtia patients. We found that microtia chondrocytes exhibited lower lipid concentrations in comparison to healthy cells, thus indicating the importance of fat storage. Moreover, we suggest that collagen is a useful biomarker for distinguishing between populations obtained from the cartilage and perichondrium because of the higher spectral contributions of collagen in the chondrocytes compared to perichondrocytes from healthy individuals and microtia patients. Our results represent a contribution to the identification of cell markers that may allow the selection of specific cell populations for cartilage tissue engineering. Moreover, the observed differences between microtia and healthy cells are essential for gaining better knowledge of the cause of microtia. It can be useful for designing novel treatment options based on further investigations of the discovered biochemical substrate alterations.

Modulation of PD‑L1 expression by standard therapy in head and neck cancer cell lines and exosomes

Although checkpoint inhibitors (CPI) have recently extended the treatment options and improved clinical response of advanced stage head and neck squamous cell carcinoma (HNSCC), treatment success remains unpredictable. Programmed cell death ligand‑1 (PD‑L1) is a key player in immunotherapy. Tumor cells, and exosomes derived therefrom, are carriers of PD‑L1 and efficiently suppress immune responses. The aim of the present study was to analyze the influence of established therapies on PD‑L1 expression of HNSCC cell lines and their exosomes. The HNSCC cell lines, UM‑SCC‑11B, UM‑SCC‑14C and UM‑SCC‑22C were treated with fractionated radiotherapy (RT; 5x2 Gy), cisplatin (CT) and cetuximab (Cetux) as monotherapy, or combined therapy, chemoradiotherapy (CRT; RT and CT) or radioimmunotherapy (RT and Cetux). The expression of PD‑L1 and phosphorylated (p)ERK1/2 as a mediator of radioresistance were assessed using western blotting, immunohistochemistry and an ex vivo vital tissue culture model. Additionally, exosomes were isolated from concentrated supernatants of the (un‑)treated HNSCC cell lines by size exclusion chromatography. Exosomal protein expression levels of PD‑L1 were detected using western blotting and semi‑quantitative levels were calculated. The functional impact of exosomes from the (un‑)treated HNSCC cell lines on the proliferation (MTS assay) and apoptosis (Caspase 3/7 assay) of the untreated HNSCC cell lines were measured and compared. The HNSCC cell lines UM‑SCC‑11B and UM‑SCC‑22B showed strong expression of pERK1/2 and PD‑L1, respectively. RT upregulated the PD‑L1 expression in UM‑SCC‑11B and UM‑SCC‑14C and in exosomes from all three cell lines. CT alone induced PD‑L1 expression in all cell lines. CRT induced the expression of PD‑L1 in all HNSCC cell lines and exosomes from UM‑SCC‑14C and UM‑SCC‑22B. The data indicated a potential co‑regulation of PD‑L1 and activated ERK1/2, most evident in UM‑SCC‑14C. Exosomes from irradiated UM‑SCC‑14C cells protected the unirradiated cells from apoptosis by Caspase 3/7 downregulation. The present study suggested a tumor cell‑mediated regulation of PD‑L1 upon platinum‑based CRT in HNSCC and in exosomes. A co‑regulation of PD‑L1 and MAPK signaling response was hypothesized.

[Intratympanic Drug Application - Indication and Procedure]

Neurootologic disorders of the inner ear associated with symptoms such as tinnitus, vertigo, and hearing loss are common and often cause significant distress to affected patients. Treatment options are usually limited. There are now some indications for which intratympanic drug application is a possible treatment option. Intratympanic drug administration is a simple, inexpensive therapy option with few side effects that can be used on an outpatient basis. Therefore, it should not be disregarded when indicated.

Artificial intelligence directed development of a digital twin to measure soft tissue shift during head and neck surgery

Digital twins derived from 3D scanning data were developed to measure soft tissue deformation in head and neck surgery by an artificial intelligence approach. This framework was applied suggesting feasibility of soft tissue shift detection as a hitherto unsolved problem. In a pig head cadaver model 104 soft tissue resection had been performed. The surface of the removed soft tissue (RTP) and the corresponding resection cavity (RC) was scanned (N = 416) to train an artificial intelligence (AI) with two different 3D object detectors (HoloLens 2; ArtecEva). An artificial tissue shift (TS) was created by changing the tissue temperature from 7,91±4,1°C to 36,37±1,28°C. Digital twins of RTP and RC in cold and warm conditions had been generated and volumes were calculated based on 3D surface meshes. Significant differences in number of vertices created by the different 3D scanners (HoloLens2 51313 vs. ArtecEva 21694, p<0.0001) hence result in differences in volume measurement of the RTC (p = 0.0015). A significant TS could be induced by changing the temperature of the tissue of RC (p = 0.0027) and RTP (p = <0.0001). RC showed more correlation in TS by heating than RTP with a volume increase of 3.1 μl or 9.09% (p = 0.449). Cadaver models are suitable for training a machine learning model for deformable registration through creation of a digital twin. Despite different point cloud densities, HoloLens and ArtecEva provide only slightly different estimates of volume. This means that both devices can be used for the task.TS can be simulated and measured by temperature change, in which RC and RTP react differently. This corresponds to the clinical behaviour of tumour and resection cavity during surgeries, which could be used for frozen section management and a range of other clinical applications.

[Recommendations of the German Society of Otorhinolaryngology, Head and Neck Surgery (DGHNO-KHC) for the granting of resident training program authorizations]

The 2018 template for otorhinolaryngology specialist training of the German Medical Association is increasingly implemented by the federal associations. In this regard, the German Society recommended an otorhinolaryngology resident training plan for Otorhinolaryngology, Head and Neck Surgery (DGHNO-KHC) together with the Professional Association of German Otorhinolaryngologists as a suggested guideline for the federal medical associations. In this context, the state medical associations currently work on criteria on the basis of which otorhinolaryngologists and their training institutions can be granted authority for such a certified otorhinolaryngology resident training program.The DGHNO-KHC last made recommendations for the granting of authorizations for specialist training in otorhinolaryngology in 1999. Many contents have changed as a result of the 2018 model specialist training regulations. Therefore, a scientifically formulated proposal for the granting of continuing education authorizations is herewith provided as recommendation to the federal state medical associations.

Plasma-derived small extracellular vesicles unleash the angiogenic potential in head and neck cancer patients

BACKGROUND

In Head and neck cancer (HNC) angiogenesis is essential for tumor progression and metastasis. Small extracellular vesicles (sEVs) from HNC cell lines alter endothelial cell (EC) functions towards a pro-angiogenic phenotype. However, the role of plasma sEVs retrieved from HNC patients in this process is not clear so far.

METHODS

Plasma sEVs were isolated on size exclusion chromatography columns from 32 HNC patients (early-stage UICC I/II: 8, advanced-stage UICC III/IV: 24), 12 patients with no evident disease after therapy (NED) and 16 healthy donors (HD). Briefly, sEVs were characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), BCA protein assays and Western blots. Levels of angiogenesis-associated proteins were determined using antibody arrays. The interaction of fluorescently-labeled sEVs with human umbilical vein ECs was visualized by confocal microscopy. The functional effect of sEVs on tubulogenesis, migration, proliferation and apoptosis of ECs was assessed.

RESULTS

The internalization of sEVs by ECs was visualized using confocal microscopy. Based on antibody arrays, all plasma sEVs were enriched in anti-angiogenic proteins. HNC sEVs contained more pro-angiogenic MMP-9 and anti-angiogenic proteins (Serpin F1) than HD sEVs. Interestingly, a strong inhibition of EC function was observed for sEVs from early-stage HNC, NED and HD. In contrast, sEVs from advanced-stage HNC showed a significantly increased tubulogenesis, migration and proliferation and induced less apoptosis in ECs than sEVs from HD.

CONCLUSIONS

In general, plasma sEVs carry a predominantly anti-angiogenic protein cargo and suppress the angiogenic properties of ECs, while sEVs from (advanced-stage) HNC patients induce angiogenesis compared to HD sEVs. Thus, tumor-derived sEVs within the plasma of HNC patients might shift the angiogenic switch towards angiogenesis.

The effects of COVID-19 on the vestibular system

Introduction

The symptoms and severity of SARS-CoV-2 infection vary greatly across the spectrum, from asymptomatic infection to severe pneumonia with acute respiratory distress syndrome and even death. Dizziness is a frequently reported symptom of SARS-CoV-2 viral infection. However, the extent to which this symptom results from the effect of SARS-CoV-2 on the vestibular system remains unclear.

Materials and methods

In the present single-center, prospective cohort study, patients with a previous SARS-CoV-2 infection underwent a vestibular assessment consisting of the Dizziness Handicap Inventory to assess dizziness during and after infection, a clinical examination, the video head impulse test, and the subjective visual vertical test. When the subjective visual vertical test result was abnormal, vestibular-evoked myogenic potentials were performed. Vestibular testing results were compared to pre-existing normative data of healthy controls. In addition, we performed a retrospective data analysis of patients admitted to hospital presenting with acute symptoms of dizziness who were also diagnosed with acute SARS-CoV-2 infection.

Results

A total of 50 participants have been enrolled. During and after the SARS-CoV-2 infection, women were significantly more likely than men to suffer from dizziness. A significantly reduced semicircular canal or otolith function was not observed in either women or men. Acute SARS-CoV-2 infection was diagnosed in nine patients who presented to the emergency room with acute vestibular syndrome. Six of the patients exhibited acute unilateral peripheral vestibulopathy upon diagnosis. A different patient was diagnosed with vestibular migraine, and two individuals had a posterior inferior cerebellar artery infarct revealed by magnetic resonance imaging.

Discussion/conclusion

Overall, a persisting structural affection of the vestibular system by SARS-CoV-2 seems to be unlikely and could not be confirmed by vHIT, SVV, and VEMPS in our study. It seems possible but unlikely that SARS-CoV-2 induces acute vestibulopathy. Nevertheless, dizziness is a common symptom in patients with COVID-19, which should be taken and worked through seriously.

[The potential of complementary music interventions in patients with head and neck cancer]

PURPOSE

The established treatment regimen for patients suffering from cancer in the head and neck region often leads to physical and mental health problems and therefore can significantly reduce the quality of life (QoL) in these patients. The available data indicate that additional complementary treatments, such as music interventions, may improve patients' QoL and compliance and reduce symptoms during therapy.

METHODS

Anonymous data collection using a self-designed questionnaire was conducted in patients suffering from cancer in the head and neck area in our outpatient department. The questionnaire particularly asked the patients about their need and interest in music interventions during therapy.

RESULTS

In total, 138 patients were consecutively enrolled in the study. The mean age was 64.9 years, including 68.1% men and 31.9% women. Only 11.5% listened to music regularly during their therapy at the time of data collection, yet 52.2% stated that they would be interested in music interventions. Patients especially conceived the relaxing and encouraging effects from listening to music. Most patients would prefer group therapies (56%) or listening to their own music (36.6%).

CONCLUSION

Our data suggest that there is a need for music interventions in patients suffering from cancer in the head and neck, as they anticipate they would experience positive effects, including reduced somatic and non-somatic symptoms and improved QoL. The lack of homogenous data emphasizes the need for further trials in the field of complementary music interventions to establish science-based concepts in the future.

Postoperative adjuvant radiochemotherapy with cisplatin versus adjuvant radiochemotherapy with cisplatin and pembrolizumab in locally advanced head and neck squamous cell carcinoma- the study protocol of the Adrisk trial

Most of the patients with head and neck squamous cell carcinoma (HNSCC) are diagnosed with locally advanced disease. Standards of care for curative-intent treatment of this patient group are either surgery and adjuvant radio(chemo)therapy (aRCT) or definitive chemoradiation. Despite these treatments, especially pathologically intermediate and high-risk HNSCC often recur. The ADRISK trial investigates in locally advanced HNSCC and intermediate and high risk after up-front surgery if the addition of pembrolizumab to aRCT with cisplatin improves event-free sur-vival compared to aRCT alone. ADRISK is a prospective, randomized controlled investiga-tor-initiated (IIT)-phase II multicenter trial within the German Interdisciplinary Study Group of German Cancer Society (IAG-KHT). Patients with primary resectable stage III and IV HNSCC of the oral cavity, oropharynx, hypopharynx and larynx with pathologic high (R1, extracapsular nodal extension) or intermediate risk (R0 <5 mm; N≥2) after surgery will be eligible. Two hun-dred forty patients will be randomly assigned (1:1) to either standard aRCT with cisplatin (standard arm) or aRCT with cisplatin + pembrolizumab (200 mg iv, in 3-week cycle, max. 12 months) (interventional arm). Endpoints are event-free and overall survival. Recruitment started in August 2018 and is ongoing.

The effect of complementary music intervention on the patients' quality of life after septoplasty and rhinoplasty

PURPOSE

Quality of life (QoL) assessment has emerged as an important evaluation tool for therapeutic treatments. The positive impact of complementary music interventions on QoL has been demonstrated in the literature, particularly in chronic and malignant diseases. However, its benefits during the perioperative period in head and neck patients have not been investigated thus far.

METHODS

Head and neck patients undergoing septoplasty and rhinoplasty were prospectively randomized and consecutively included in the trial. Passive music intervention (60 min per day) was applied to the intervention group. QoL was assessed using the Nasal Obstruction Symptom Evaluation (NOSE) questionnaire and the Functional Rhinoplasty Outcome Inventory 17 (FROI-17) questionnaire at three visits during the postoperative phase. Pain was measured using a visual analogue scale.

RESULTS

Forty-four patients were enrolled in the study. The NOSE score between the control group and the intervention group in the septoplasty arm differed significantly at visit #2 (p < 0.001) and visit #3 (p < 0.015). For the rhinoplasty study arm, significant differences in the FROI-17 score were also found at visit #2 and visit #3 (p = 0.04).

CONCLUSION

Complementary music interventions can considerably improve patients' QoL during the postoperative period. Furthermore, passive music interventions may be easily implemented in clinical practice as an additional cost-effective treatment with ubiquitous availability.

Optimisation of Conditions for the Formation of Spheroids of Head and Neck Squamous Cell Carcinoma Cell Lines for Use as Animal Alternatives

The use of in vitro 3-D cell culture models in cancer research has yielded substantial gains in knowledge on various aspects of tumour biology. Such cell culture models could be useful in the study of head and neck squamous cell carcinoma (HNSCC), where mimicking intratumoral and intertumoral heterogeneity is especially challenging. Our research aims to establish 3-D spheroid models for HNSCC that reproduce in vitro the connections between tumour cells and the surrounding microenvironment. The aims of this study were to determine the optimal conditions for the culture and use of spheroids from HNSCC cell lines and optimal timepoint for using the spheroids obtained, to evaluate the effects of coculture with tumour-specific fibroblasts on spheroid formation, and to investigate spheroid responses to cisplatin treatment. Four HNSCC cell lines (UMSCC-11A, UMSCC-11B, UMSCC-22B and UD-SCC-01) were seeded in flat or round bottom well ultra-low attachment spheroid plates, and spheroid formation was evaluated. The HNSCC cell lines were then cocultured with stromal cells of the tumour microenvironment, producing an accelerated formation of dense spheroids. The viability of cells within the spheroids was assessed during cell culture by using a fluorescent dye. Our results suggest that: three out of the four cell lines tested could form usable spheroids with acceptable viability; the addition of stromal cells did not improve the number of viable cells; and the use of round bottom well plates supported the formation of a single spheroid, whereas flat bottom well plates led to the formation of multiple spheroids of different sizes.

Erwägungen zur Durchführung und Qualitätssicherung ambulanter Operationen im HNO-Bereich in Deutschland

Hintergrund Die deutsche Gesundheitspolitik hat eine Ausweitung ambulanter Operationen und Verfahren propagiert und die Diskussion darüber eingeleitet. Die HNO-Heilkunde bietet Möglichkeiten, derzeit stationär durchgeführte Eingriffe ambulant zu erbringen.

Methoden Die Deutsche Gesellschaft für HNO-Heilkunde, Kopf- und Hals-Chirurgie und der Deutsche Berufsverband der HNO-Ärzte haben Arbeitsgruppen ins Leben gerufen, die die HNO-fachlichen Aspekte der Leistungsverlagerungen in den ambulanten Bereich beurteilen und bewerten sollen. Die Arbeitsgruppen bekamen den Auftrag dabei organisatorische, strukturelle und personelle Definitionen der Qualitätssicherung zu erarbeiten und zu berücksichtigen.

Empfehlung Es wurden ausführlich Tatbestände bestimmt, die eine ambulante Operation im HNO-Fachgebiet ausschließen. Grundlage bildeten hierbei sowohl operationsbedingte als auch patientenbedingte Tatbestände. Schließlich wurden Operationen benannt, die als ambulante Operationen durchgeführt werden können.

Diskussion Es erfolgte eine HNO-fachliche Bewertung. Voraussetzung für eine Ambulantisierung ist eine Neuordnung der Vergütung. Das bisherige DRG- und EBM-System bieten hierzu keinen befriedigenden Rahmen, der EBM ermöglicht keine wirtschaftliche Erbringung operativer Eingriffe im HNO-Bereich. Die Entwicklung eines adäquaten Finanzierungsmodells ist für einen Erfolg der Umsetzung genauso zwingend erforderlich wie die Integration und Finanzierung der HNO-ärztlichen Weiterbildung.

Long-Term Results of a Multimodal Treatment Regimen in Patients With Auricular Keloids

Objectives: The treatment of auricular keloids is challenging, as they tend to recur; further, the treatment may impact quality of life and implies cosmetic and functional impairment for each patient. There is no standardized therapeutic concept established, and the literature is lacking long-term results of available treatment modalities. Methods: Patients suffering from auricular keloids were included in the study. All patients had undergone surgical resection, intralesional injection of triamcinolone acetonide (TAC), and the application of an individual pressure splint. Quality of life (QoL) was assessed using the keloid intervention benefit inventory 21 (KIBI-21). Further analysis was carried out for patients without (group 1) and with (group 2) recurrence of the keloid. Results: In total, 50 keloids with a mean follow-up period of 59 months (range 6-137 months) could be analyzed. In nine cases (18%), a keloid recurrence was found during the observation period. The assessment of QoL differed significantly between study groups at P = 0.04, as well as for the subcategories General Health (GH) and Physical Health (PH). No differences were found for the categories Social Impact (SI) and Self-Esteem (SE). Conclusions: The multimodal subsequent treatment regimen consisting of surgical resection, intralesional TAC injection, and the application of an individual magnetic pressure splint shows good results concerning long-term recurrence rates. The treatment method shows positive effects on the QoL, especially in the measured categories GH and PH.

In situ regeneration of nasal septal defects using acellular cartilage enhanced with platelet-derived growth factor

Nasal septum defects can currently only be reconstructed using autologous cartilage grafts. In this study, we examine the reconstruction of septal cartilage defects in a rabbit model using porcine decellularized nasal septal cartilage (DNSC) functionalized with recombinant platelet-derived growth factor-BB (PDFG-BB). The supportive function of the transplanted DNSC was estimated by the degree of septum deviation and shrinkage using magnetic resonance imaging (MRI). The biocompatibility of the transplanted scaffolds was evaluated by histology according to international standards. A study group with an autologous septal transplant was used as a reference. In situ regeneration of cartilage defects was assessed by histological evaluation 4 and 16 weeks following DNSC transplantation. A study group with non-functionalized DNSC was introduced for estimation of the effects of PDFG-BB functionalization. DNSC scaffolds provided sufficient structural support to the nasal septum, with no significant shrinkage or septal deviations as evaluated by the MRI. Biocompatibility analysis after 4 weeks revealed an increased inflammatory reaction of the surrounding tissue in response to DNSC as compared to the autologous transplants. The inflammatory reaction was, however, significantly attenuated after 16 weeks in the PDGF-BB group whereas only a slight improvement of the biocompatibility score was observed in the untreated group. In situ regeneration of septal cartilage, as evidenced by the degradation of the DNSC matrix and production of neocartilage, was observed in both experimental groups after 16 weeks but was more pronounced in the PDFG-BB group. Overall, DNSC provided structural support to the nasal septum and stimulated in situ regeneration of the cartilage tissue. Furthermore, PDFG-BB augmented the regenerative potential of DNSC and enhanced the healing process, as demonstrated by reduced inflammation after 16 weeks.

Conjoint analysis of OPRPN and SMR3A protein expression as potential predictive biomarkers for head and neck squamous cell carcinoma after radiotherapy

Increased submaxillary gland androgen‑regulated protein 3A (SMR3A) expression was previously shown to serve as an independent risk factor for oropharyngeal squamous cell carcinoma (OPSCC) and as a surrogate biomarker for active estrogen receptor 2 signaling in radioresistant tumor cells. In the present study, it was aimed to unravel the expression and clinical significance of another member of the opiorphin family, opiorphin prepropeptide (OPRPN), in the radiotherapy for head and neck squamous cell carcinoma (HNSCC). Expression of SMR3A and OPRPN were analyzed for the prior and post fractionated irradiation (4x2 Gy) by double immunofluorescence staining in established HNSCC cell lines as well as by immunohistochemical (IHC) staining in ex vivo tumor tissues. Next, in a retrospective experimental cohort study, primary tumor samples from OPSCC patients (n=96), who received definitive surgery and adjuvant radiotherapy were reviewed, and expression levels of OPRPN protein were detected by IHC. Immunoreactivity scores (IRS) were associated with pathological and clinical risk factors by Chi‑square analysis. Survival analysis was performed by using the Kaplan‑Meier plot, log‑rank test and Cox regression analysis. The expression levels of OPRPN and SMR3A protein were both induced by fractionated irradiation in vitro and ex vivo. In primary tumor samples, IRS of OPRPN was significantly higher than scores of SMR3A expression and positively correlated with expression patterns of SMR3A. SMR3A was confirmed to serve as an unfavorable factor, while OPRPN protein had no significant association with the clinical outcome of patients with OPSCC. A combinational analysis revealed that the subgroup with SMR3A^highOPRPN^low staining pattern had the worst clinical outcome among the various subgroups. Multivariate Cox regression analyses indicated that high expression of SMR3A serves as an independent unfavorable biomarker, while increased expression of OPRPN appears to exert protective function. In summary, the present study indicated that SMR3A and OPRPN serve as potential prognostic markers for HNSCC after radiotherapy.

An in vitro study on the effect of bevacizumab on endothelial cell proliferation and VEGF concentration level in patients with hereditary hemorrhagic telangiectasia

Previous studies have demonstrated that vascular endothelial growth factor (VEGF) is upregulated in patients with hereditary hemorrhagic telangiectasia (HHT). The use of Bevacizumab as an anti-angiogenic treatment agent seems promising. The purpose of the present in vitro study was to determine the efficacy and potential toxicity levels of bevacizumab on cell proliferation and VEGF concentrations in endothelial cells of HHT patients. In this in vitro study, endothelial cells from patients with HHT and HUVECs (control) were incubated with different concentration levels of bevacizumab (2, 4, 6, 8 or 10 mg/ml). After 24, 48 or 72 h, the cell proliferation was assessed by Alamar Blue^® Assay and the VEGF levels in the cell culture supernatants were measured by VEGF-ELISA. All endothelial cells incubated with bevacizumab showed an initial decrease in cell proliferation. Cell proliferation recovered within 72 h in cell cultures incubated with concentration levels of up to 4 mg/ml bevacizumab, whereas those incubated with higher concentration levels showed a continuous decline in cell proliferation. VEGF expression decreased after 24 h in cell cultures incubated with bevacizumab concentration levels of 2 and 4 mg/ml but increased again after 48 h. Cell cultures incubated with bevacizumab concentration levels of 10 mg/ml showed a constant decline in VEGF expression without any tendency for recovery. Translating these results into daily clinical practice, the present study suggests that the intranasal submucosal injection of bevacizumab in HHT patients should not exceed a concentration level of 4 mg/ml. Overall, higher bevacizumab concentration levels not only reduce VEGF expression but pose a higher risk of toxic effects on endothelial cells as they jeopardize cell proliferation.

Targeted Treatment of HPV16-positive and -negative SCC Cells With Small Molecule Tyrosine Kinase Inhibitors and Everolimus Affects MMP2 and MMP14 Expression

BACKGROUND/AIM

The rise of targeted therapies in the treatment of head and neck squamous cell carcinoma (HNSCC) has considerably widened the treatment range. Matrix metalloproteinases (MMPs) are key regulators of the tumor development of many cancer entities, which makes them a promising target for new treatment options. We examined the expression patterns of MMP2 and MMP14 in human papillomavirus (HPV)-positive and -negative SCC lines after treatment with small molecule tyrosine kinase inhibitors (TKIs) and a mechanistic target of rapamycin (mTOR) inhibitor in vitro.

MATERIALS AND METHODS

Cells of two human HPV-negative cell lines (UMSCC-11A/-14C) and one HPV-positive cell line (CERV196) were incubated with 20 μmol/l of erlotinib, gefitinib, nilotinib, dasatinib, or everolimus for 24-96 h. Cell proliferation was assessed by proliferation assay and the protein concentrations of MMP2 and MMP14 by sandwich enzyme-linked immunosorbent assay. For statistical analysis, the results were compared with those of untreated SCC cells.

RESULTS

MMP2 and MMP14 were expressed in all three tested cell lines; expression levels were highest in the UMSCC-14C cell line. The tested TKIs significantly (p<0.05) reduced MMP2 expression in the UMSCC-14C cell line. In the HPV-positive cell line, the drugs led to an increase in MMP2 and MMP14 expression.

CONCLUSION

Dysregulations in MMP signaling are involved in tumorigenesis and metastasis of HNSCCs; MMP2 has been noted as a potential biomarker. The expression of MMP2 and MMP14 is influenced effectively by small molecule TKIs and everolimus. Based on our data, future research should concentrate on a better understanding of the interplay between tumor microenvironment and tumor cells in vitro and in vivo.

Anosmia Testing as Early Detection of SARS-CoV-2 Positivity; A Prospective Study under Screening Conditions

Sudden onset of anosmia is a phenomenon often associated with developing COVID-19 disease and has even been described as an initial isolated symptom in individual cases. In this case-control study, we investigated the feasibility of this condition as a suitable screening test in a population at risk. We performed a prospective study with a total of 313 subjects with suspected SARS-CoV-2 infection. In parallel to routine PCR analysis, a modified commercial scent test was performed to objectify the presence of potential anosmia as a predictor of SARS-CoV-2 positivity. Furthermore, a structured interview assessment of the participants was conducted. A total of 12.1% of the study participants had molecular genetic detection of SARS-CoV-2 infection in the nasopharyngeal swab. It could be demonstrated that these subjects had a significantly weaker olfactory identification performance of the scents. Further analysis of the collected data from the scent test and medical history via random forest (Boruta) algorithm showed that no improvement of the prediction power was achieved by this design. The assay investigated in this study may be suitable for screening general olfactory function. For the screening of COVID-19, it seems to be affected by too many external and internal biases and requires too elaborate and selective pre-test screening.

Biomarkers and 3D models predicting response to immune checkpoint blockade in head and neck cancer (Review)

Immunotherapy has evolved into a powerful tool in the fight against a number of types of cancer, including head and neck squamous cell carcinomas (HNSCC). Although checkpoint inhibition (CPI) has definitely enriched the treatment options for advanced stage HNSCC during the past decade, the percentage of patients responding to treatment is widely varying between 14-32% in second-line setting in recurrent or metastatic HNSCC with a sporadic durability. Clinical response and, consecutively, treatment success remain unpredictable in most of the cases. One potential factor is the expression of target molecules of the tumor allowing cancer cells to acquire therapy resistance mechanisms. Accordingly, analyzing and modeling the complexity of the tumor microenvironment (TME) is key to i) stratify subgroups of patients most likely to respond to CPI and ii) to define new combinatorial treatment regimens. Particularly in a heterogeneous disease such as HNSCC, thoroughly studying the interactions and crosstalking between tumor and TME cells is one of the biggest challenges. Sophisticated 3D models are therefore urgently needed to be able to validate such basic science hypotheses and to test novel immuno-oncologic treatment regimens in consideration of the individual biology of each tumor. The present review will first summarize recent findings on immunotherapy, predictive biomarkers, the role of the TME and signaling cascades eliciting during CPI. Second, it will highlight the significance of current promising approaches to establish HNSCC 3D models for new immunotherapies. The results are encouraging and indicate that data obtained from patient-specific tumors in a dish might be finally translated into personalized immuno-oncology.

Prognostic Factors for the Therapeutic Performance of Cisplatin in Head and Neck Malignancies

Introduction

For squamous cell carcinoma of the head and neck (HNSCC), cisplatin is used as primary or adjuvant (radio)chemotherapy. In terms of dosage, two main regimens are used, weekly 40mg/m² or 3-weekly 100mg/m². For an optimal outcome, the highest possible cumulative total dose of cisplatin is aimed for. The selection of the scheme is patient-specific, but the factors for the selection of the optimal scheme have not yet been conclusively researched. The aim of this study was to find correlations between initial laboratory values and the cumulative total dose of cisplatin, as well as any correlations between early laboratory values or their dynamics and later laboratory values or their dynamics to provide support in the selection of the chemo regimen.

Material and Methods

In this retrospective study, the clinical data and laboratory values, namely glomerular filtration rate (GFR), hemoglobin, albumin, leucocyte, erythrocyte and platelet count, over the course of time of 79 patients with HNSCC who had received chemotherapy with cisplatin in our clinic between 2018 and 2021 were evaluated.

Results

Patients on 3-weekly regimens achieved a higher mean cumulative total dose of cisplatin than patients on weekly regimens (214.18 ± 65.95 vs 183.33 ± 65.2 mg/m²). Significant positive correlations were seen for total cumulative dose of cisplatin with initial GFR (p=0.001, Pearson's r=0.364), initial hemoglobin (p=0.035, r=0.237), initial erythrocyte (p=0.002, r=0.337), and initial albumin (p=0.002, r=0.337). There were no significant correlations for initial leucocyte or platelets. Regarding the dynamics of the laboratory values under the first chemo administration, no correlation was found with later laboratory values or dynamics.

Discussion and Conclusion

As in other prospective studies, our retrospective analysis found a higher cumulative total dose in the 3-weekly regimen. As this seems to correlate positively with patient outcome, superiority of the 3-weekly regimen over the weekly regimen can be assumed. Functioning organ systems, especially of the bone marrow and kidneys, are associated with an increased cumulative total dose and can therefore be regarded as predictive factors. Regular monitoring of laboratory values is nevertheless essential throughout the entire course of chemotherapy.

Post-COVID-19 Impairment of the Senses of Smell, Taste, Hearing, and Balance

Background: Various symptoms have been associated with COVID-19, but little is known about the impacts of COVID-19 on the sensory system, risk factors, and the duration of symptoms. This study assesses olfactory, gustatory, hearing, and vestibular systems after COVID-19. Methods: This cross-sectional, single-center study involved 50 patients one to six months after COVID-19 and reports their patient records and the extent, onset, and duration of olfactory, gustatory, hearing, and balance disorders using questionnaires during and after COVID-19. Sensory symptoms were objectively studied using the following clinical tests after COVID-19 Sniffin’ Sticks, taste tests, tone/speech audiometry, and video head impulse test. Results: Post-COVID-19-patients were suffering from olfactory and gustatory impairment for up to six months. According to the Dizziness Handicap Inventory, balance disorders were less noticed: Overall, about 40% of the patients during COVID-19 and nearly all patients recovered within six months. After COVID-19, clinical tests revealed that 75% were suffering from hyposomnia/anosmia, and 20% of all patients reported mild hypogeusia for up to six months. Vestibular disorders and hearing impairment rarely/did not occur. Females were significantly more affected by sensory impairments than males. Conclusions: COVID-19 particularly caused olfactory and gustatory impairment; balance disorders were present too; vestibular and auditory symptoms were negligible.

3D cell culture alters signal transduction and drug response in head and neck squamous cell carcinoma

Epidermal growth factor receptor (EGFR) upregulation is a typical characteristic of head and neck squamous cell carcinoma (HNSCC). However, tyrosine kinase inhibitors have not yet been able to achieve enough therapeutic benefit in clinical trials to justify their use in standard therapy regimens. At present, little is known about the reasons for this treatment failure. In the present study, the HNSCC cell lines UM-SCC-11B and UM-SCC-22B were tested for their response to tyrosine kinase inhibitors (TKI) under 2D and 3D cell culture conditions. Absorption and luciferase-based viability assays were used for this, as well as optical evaluation via fluorescence microscopy. In addition, EGFR and HER3 expression as well as the downstream signalling pathways PI3K/AKT/mTOR and RAS/RAF/MEK/ERK were investigated using western blotting. Cell line UM-SCC-11B revealed a strong resistance to lapatinib under 3D cell culture conditions, while a good response to TKI therapy was observed under 2D cell culture conditions. An associated overexpression of phosphorylated HER3 under 3D cell culture conditions offered a plausible explanation for the altered treatment response. The results of the present study represent an idea of how signalling mechanisms of cancer cells can be changed using different cell culture methods. Overall, 3D cell culture could be an important component in the analysis of resistance mechanisms in cancer therapy.

Modulation of the inflammatory response to decellularized collagen matrix for cartilage regeneration

Decellularized extracellular matrices (DECM) are among the most common types of materials used in tissue engineering due to their cell instructive properties, biodegradability, and accessibility. Particularly in cartilage, a natural collagen type II matrix can be a promising means to provide the necessary cues and support for chondrogenic stem and progenitor cells (CSPCs). However, efficient remodeling of the transplanted DECM is largely dependent on the host immune response, with macrophages playing the central role in orchestrating both inflammatory and regenerative processes. Here we assessed the reaction of human primary macrophages to the cartilage DECM. Our findings show that the xenogeneic collagen matrix can elicit a mixed response in human macrophages, whereby the inflammatory response (M1) and the activation of remodeling (M2) type of macrophages are both present. Additionally, we demonstrate the inhibitory effect of macrophage response on the migratory capacity of human CSPCs. We further show that the inflammatory reaction of macrophages to the cartilage DECM, as well as the resulting inhibitory effects on CSPC migration, can be attenuated by interleukin-4 (IL-4). Finally, we demonstrate that IL-4 can effectively bind the matrix, thereby modulating macrophage response by reducing the inflammatory reaction and inducing the M2 phenotype.

[Differential diagnosis of intraorbital masses - a narrative review]

OBJECTIVE

Intraorbital masses represent a condition that is frequently threatening for the visual system. A rigorous differential diagnosis is essential to promptly initiate appropriate therapy and optimize prognosis.

MATERIALS/METHODS

Narrative review of current literature and expert recommendations. For further illustration we describe the case of a 71-year-old male admitted to our department three months after sinus surgery. Postoperative intraorbital hematoma of the right orbit had been treated conservatively with antibiotics/corticosteroids, leading to a near-complete unilateral visual loss. The immediate surgical intervention aimed at decompression of the orbit and the optical nerve. Due to the delay, the intervention could not prevent formation of a lipogranuloma. Inflammatory phases associated with the lipogranuloma are successfully managed by conservative treatment based on multidisciplinary recommendations.

RESULTS

In the case reported, delay of surgical therapy acted as a cause of intraorbital lipogranuloma formation. Literature supports our recommendation of immediate surgical intervention in case of acute retrobulbar hematoma. Besides acute conditions, intraorbital masses can be a sign of systemic disease. In every case, a multidisciplinary therapeutic approach is required for adequate management.

CONCLUSIONS

Intraorbital masses can occur as a complication of trauma or e.g. sinus surgery. On the other hand they can be a sign of systemic disease. Timely diagnosis and treatment prevents from visual loss. That is why rigorous differential diagnosis is essential for every discipline managing intraorbital lesions.

Vestibular testing in children - The suppression head impulse (SHIMP) test

INTRODUCTION

The incidence of vestibular disorders and vertigo during childhood is increasing and pediatric clinicians have become more sensitive to children's balance disorders; thus, there is a need for appropriate detection test procedures for peripheral vestibular hypofunction. In order to ensure a reliable diagnosis and minimize misdiagnosis, a standardized clinical procedure via careful history and clinical examination is recommended. However, children, especially, are often unable to verbalize "vertigo" in a concrete manner, which often necessitates a consultation with a pediatrician holding nonspecific symptoms. The so-called suppression of the head impulse test (SHIMPs) represents a modification of the video head impulse test (HIMP) and is used for a more sensitive assessment of residual vestibular functions. In adults, SHIMPs are already an established diagnostic method. Nevertheless, to date, nothing is known about the applicability and standard values in childhood.

MATERIAL AND METHODS

In this monocentric, prospective study, we investigated whether SHIMPs enable a sensitive functional analysis of the vestibular system in healthy children of different ages. For this purpose, SHIMPs were performed in 40 children aged 3-18 years.

RESULTS

In this study, we demonstrated that SHIMPs can be easily performed in children (3-18 years). It is vital that the test be appropriately explained for children to ensure sufficient test tolerance and compliance.

CONCLUSION

SHIMPs are a helpful supplement to clinically established vestibular tests such as the HIMP in pediatric vestibular balance disorder diagnostics and can be integrated into the clinical routine, especially in children who have minimal verbal abilities or understanding of the instructions for HIMP. Similar to the HIMP, SHIMPs are characterized by a short test duration and a high tolerance.

[Time management in operating rooms-a cross-sectional study to evaluate estimated and objective durations of otorhinolaryngologic surgical procedures]

Hintergrund

Die Gestaltung des Operations(Op.)-Programms im klinischen Alltag ist von hoher Wichtigkeit für die Wirtschaftlichkeit. Gleichzeitig muss die Einhaltung von Arbeitszeiten unterschiedlicher Berufsgruppen berücksichtigt werden.

Ziel der Arbeit

Um Fehlerquellen bei der Planung aufzudecken, wurden durch Chirurgen geschätzte mit objektiv erhobenen Zeiten (u. a. Schnitt-Naht-Zeit) verglichen.

Material und Methoden

In einer retrospektiven Analyse wurden 1809 Operationen im Jahr 2018 (22 verschiedene Op.-Arten) durch 31 Operateure (12 Fach- [FÄ] und 19 Assistenzärzte [AÄ]) hinsichtlich ihrer Dauer verglichen und mittels Mann-Whitney-U-Test auf Signifikanz geprüft.

Ergebnisse

Der Vergleich der objektiven Zeiten von FÄ und AÄ zeigt signifikante Unterschiede in der Schnitt-Naht-Zeit bzw. der Summe aus Schnitt-Naht-Zeit und Zeit der chirurgischen Maßnahmen für 6 von 15 Op.-Arten (p < 0,001). Die durch FÄ geschätzte Nachbereitungszeit wich bei 2 von 22 Op.-Arten von der objektiven Zeit ab (p < 0,05), die durch AÄ geschätzte Zeit bei 7 von 15 Op.-Arten (p < 0,05). Hinsichtlich der Schnitt-Naht-Zeit verschätzten sich FÄ bei 7 von 22 (p < 0,05), AÄ bei 3 von 15 (p < 0,05) Op.-Arten. Die durch FÄ geschätzte Vorbereitungszeit wich bei 16 von 22 Op.-Arten signifikant von der objektiven Zeit ab (p < 0,05), bei AÄ bei 7 von 15 (p < 0,001). Vor- und Nachbereitungszeiten wurden durch FÄ unter‑, Schnitt-Naht-Zeiten überschätzt. AÄ unterschätzten alle Zeiten.

Schlussfolgerung

Bei der OP-Planung muss die Erfahrung des durchführenden Chirurgen berücksichtigt werden. Eine Verbesserung durch verminderte subjektive Fehleinschätzung kann möglicherweise mithilfe spezieller Algorithmen gelingen.

Enhanced cellular migration and prolonged chondrogenic differentiation in decellularized cartilage scaffolds under dynamic culture conditions

Lesions of aural, nasal and tracheal cartilage are frequently reconstructed by complex surgeries which are based on harvesting autologous cartilage from other locations such as the rib. Cartilage tissue engineering (CTE) is regarded as a promising alternative to attain vital cartilage. Nevertheless, CTE with nearly natural properties poses a significant challenge to research due to the complex reciprocal interactions between cells and extracellular matrix which have to be imitated and which are still not fully understood. Thus, we used a custom-made glass bioreactor to enhance cell migration into decellularized porcine cartilage scaffolds (DECM) and mimic physiological conditions. The DECM seeded with human nasal chondrocytes (HPCH) were cultured in the glass reactor for 6 weeks and examined by histological and immunohistochemical staining, biochemical analyses and real time-PCR at 14, 28 and 42 days. The migration depth and the number of migrated cells were quantified by computational analysis. Compared to the static cultivation, the dynamic culture (DC) fostered migration of HPCH into deeper tissue layers. Furthermore, cultivation in the bioreactor enhanced differentiation of the cells during the first 14 days, but differentiation diminished in the course of further cultivation. We consider the DC in the presented bioreactor as a promising tool to facilitate CTE and to help to better understand the complex physiological processes during cartilage regeneration. Maintaining differentiation of chondrocytes and improving cellular migration by further optimizing culture conditions is an important prerequisite for future clinical application.

Prevalence of subjective impairments of the sense of smell and taste in employees of retirement and nursing homes during SARS-CoV-2 pandemic

Aim

To investigate the usability of querying subjective impairments of the sense of smell and taste in order to improve pre‐test probability in testing for SARS‐CoV‐2. To achieve this, exploring the prevalence of these restrictions in the COVID‐19‐negative population, as well as nasal co‐symptoms.

Design

A cross‐sectional study was carried out as part of the secondary prophylaxis, following the STROBE guidelines of the EQUATOR network.

Methods

In total, 1,734 employees of retirement and nursing homes were tested for COVID‐19 and asked for subjective reduction or loss in the sense of smell and taste, furthermore about nasal co‐symptoms such as nasal obstruction and rhinorrhoea.

Results

All employees tested negative for COVID‐19. Subjective hyposmia and hypogeusia rarely occurred and were usually accompanied by other nasal symptoms such as nasal obstruction. Querying subjective hyposmia/anosmia or hypogeusia/ageusia appears to be a useful anamnestic instrument for the clinical assessment of the probability of SARS‐CoV‐2 infection.

[Professional teamwork and communication in the operating room-A narrative review]

BACKGROUND

A team in the operating room (OR) is a hierarchically structured, gender-mixed group of people belonging to different professional categories. Disparities in the objectives of the different team members under economic pressure to perform, are sources of potential conflict in the daily work routine. This may have a negative impact on patient safety and commercial efficiency of hospital management.

OBJECTIVE

The aim of this summary is to sensitize the reader to the complex of problems in daily life in the OR and to increase awareness of possible approaches to solve the difficulties in an OR. Problem solutions might be approached by improvement of communication and team building.

METHODS

Narrative review of current literature and expert recommendations by a literature search in PubMed and Medline; keywords included teamwork, communication, operating room, team building.

RESULTS AND CONCLUSION

Communication and teamwork in the OR are of immense importance for patient safety and the economic development of a hospital. Improvements in communication structure, among other things due to the implementation of a team time out and moderation from outside (OR manager) offer solutions to avoid conflicts in everyday clinical practice.

Precision Medicine Gains Momentum: Novel 3D Models and Stem Cell-Based Approaches in Head and Neck Cancer

Despite the current progress in the development of new concepts of precision medicine for head and neck squamous cell carcinoma (HNSCC), in particular targeted therapies and immune checkpoint inhibition (CPI), overall survival rates have not improved during the last decades. This is, on the one hand, caused by the fact that a significant number of patients presents with late stage disease at the time of diagnosis, on the other hand HNSCC frequently develop therapeutic resistance. Distinct intratumoral and intertumoral heterogeneity is one of the strongest features in HNSCC and has hindered both the identification of specific biomarkers and the establishment of targeted therapies for this disease so far. To date, there is a paucity of reliable preclinical models, particularly those that can predict responses to immune CPI, as these models require an intact tumor microenvironment (TME). The "ideal" preclinical cancer model is supposed to take both the TME as well as tumor heterogeneity into account. Although HNSCC patients are frequently studied in clinical trials, there is a lack of reliable prognostic biomarkers allowing a better stratification of individuals who might benefit from new concepts of targeted or immunotherapeutic strategies. Emerging evidence indicates that cancer stem cells (CSCs) are highly tumorigenic. Through the process of stemness, epithelial cells acquire an invasive phenotype contributing to metastasis and recurrence. Specific markers for CSC such as CD133 and CD44 expression and ALDH activity help to identify CSC in HNSCC. For the majority of patients, allocation of treatment regimens is simply based on histological diagnosis and on tumor location and disease staging (clinical risk assessments) rather than on specific or individual tumor biology. Hence there is an urgent need for tools to stratify HNSCC patients and pave the way for personalized therapeutic options. This work reviews the current literature on novel approaches in implementing three-dimensional (3D) HNSCC in vitro and in vivo tumor models in the clinical daily routine. Stem-cell based assays will be particularly discussed. Those models are highly anticipated to serve as a preclinical prediction platform for the evaluation of stable biomarkers and for therapeutic efficacy testing.

Regenerative Potential of Perichondrium: A Tissue Engineering Perspective

The clinical relevance of perichondrium was recognized more than a century ago. In children and adolescents, perichondrium is essential for the formation and growth of the cartilaginous part of craniofacial features and must be considered during reconstructive surgery in the head and neck area. Also in adults, perichondrium must be preserved during surgical intervention for adequate postoperative healing and cartilage maintenance. Furthermore, the regenerative function of perichondrium in the ribs enables the harvesting of the rib cartilage tissue for reconstruction of craniofacial features. With the advancement of tissue engineering, renewed attention has been focused on the perichondrium, because without this crucial tissue, the function of cartilage engineered for craniofacial reconstruction is incomplete and may not be suitable for long-term reconstructive goals. Furthermore, interest in the perichondrium was revived owing to its possible role as a microenvironment containing stem and progenitor cells. Here we will revisit seminal studies on the perichondrium and review the current literature to provide a holistic perspective on the importance of this tissue in the context of regenerative medicine. We will also highlight the functional significance of perichondrium for cartilage tissue engineering.

Presence of gustatory and olfactory dysfunction in the time of the COVID-19 pandemic

BACKGROUND

The unexpected outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused more than 49 million cases and an estimated 2,000,000 associated deaths worldwide. In Germany, there are currently more than 2,000,000 laboratory-confirmed coronavirus disease 2019 (COVID-19) cases including 51,800 deaths. However, regional differences also became apparent and with the second wave of infections, the detailed characterization of COVID-19 patients is crucial to early diagnosis and disruption of chains of infections.

METHODS

Handing out detailed questionnaires to all individuals tested for COVID-19, we evaluated the clinical characteristics of negative and positive tested individuals. Expression of symptoms, symptom duration and association between predictor variables (i.e. age, gender) and a binary outcome (olfactory and gustatory dysfunction) were assessed.

RESULTS

Overall, the most common symptoms among individuals who tested positive for SARS-CoV-2 were fatigue, headache, and cough. Olfactory and gustatory dysfunction were also reported by many SARS-CoV-2 negative individuals, more than 20% of SARS-CoV-2 negative tested individuals in our study reported olfactory and gustatory dysfunction. Independent of SARS-CoV-2 status, more females displayed symptoms of gustatory (29.8%, p = 0.0041) and olfactory dysfunction (22.9%, p = 0.0174) compared to men.

CONCLUSIONS

Bringing early SARS-CoV-2 tests to the populations at risk must be a main focus for the upcoming months. The reliability of olfactory and gustatory dysfunction in COVID-19 negative tested individuals requires deeper investigation in the future.

[Surgical Management of Salivary Gland Carcinoma]

Salivary gland carcinomas are very threatening diseases. The patient's survival depends to a large extent on planning and performing the resection. This article provides assistance with the most important surgical decisions. Using illustrative examples and practical tips the article shows how oncological salivary gland surgery can be successful.

[Validity of SARS-CoV-2 swabs taken preoperatively in children]

BACKGROUND

 Due to the limited compliance, the technically correct collection of a pooled nasopharyngeal swab is significantly more difficult in children. Especially during operations in the area of the upper respiratory tract, there is a significantly increased risk of infection with COVID-19 for everyone present in the operating room. The aim of the study is to analyze the validity of SARS-CoV-2 swabs taken preoperatively under suboptimal conditions.

MATERIAL AND METHODS

 Retrospective comparison of the PCR results of SARS-CoV-2 swaps taken preoperatively and intraoperatively from 62 children in the period from April to November 2020. Median age was 4.49 years. The PCR diagnosis was carried out one or two days preoperatively (in the case of emergency interventions on the same day) and again intraoperatively using a pooled nasopharyngeal swab.

RESULTS

 All 62 preoperatively taken swabs were negative. Deviating from the preoperative test result, one intraoperatively obtained swab was positive.

CONCLUSIONS

 Due to limited compliance, a correct preoperative swab technique (preanalytics) cannot always be assumed for children. Sufficient protective measures for everyone present in the operating room are therefore imperative. Intraoperative test should be considered if the the preoperative test was performed under difficult conditions.

Case Report: Bilateral Palsy of the Vocal Cords After COVID-19 Infection

During the COVID-19 pandemic, adverse neurological effects have been described. In addition to unspecific neurological symptoms, cranial nerve deficits have appeared as part of SARS-CoV-2 infection. In this case report, we describe a 74-year-old patient who developed bilateral paralysis of the vocal cords some weeks following his dismissal in stable condition after COVID-19 pneumonia. After ruling out central lesions, peripheral tumors, and other possible causes, therapy was initiated with methylprednisolone, inhalations, and oxygen. The patient showed no improvement, so laterofixation after Lichtenberger was performed. The dyspnea worsened after several weeks, so a laser posterior cordectomy was performed with satisfactory outcome.

Expression Patterns of CD44 and AREG Under Treatment With Selective Tyrosine Kinase Inhibitors in HPV+ and HPV- Squamous Cell Carcinoma

BACKGROUND

We investigated the expression patterns of cluster of differentiation (CD) 44 and amphiregulin (AREG), two signaling molecules essential for cell proliferation and differentiation, under the influence of selective tyrosine kinase inhibitors (TKIs) in human papillomavirus (HPV)⁺ and HPV^- squamous carcinoma cell lines.

MATERIALS AND METHODS

The protein expression of CD44 and AREG was determined by sandwich enzyme-linked immunosorbent assay in HPV^- cell lines UMSCC-11A and UMSCC-14C, and HPV⁺ CERV-196 cells after TKI treatment.

RESULTS

The expression of AREG and CD44 was dependent on the cell line's HPV status. AREG expression increased after incubation with nilotinib in HPV⁺ tumor cells. The expression of CD44 was significantly influenced by all drugs; its expression under selective epidermal growth factor receptor inhibition was mostly reduced, whereas nilotinib led to an exceptional increase of CD44 expression.

CONCLUSION

The selective drug treatment options significantly influenced the expression of CD44 and AREG in HPV^- and HPV⁺ tumor cells, constituting the need for personalized treatment options.

Augmented Reality with HoloLens® in Parotid Tumor Surgery: A Prospective Feasibility Study

INTRODUCTION

Augmented reality can improve planning and execution of surgical procedures. Head-mounted devices such as the HoloLens® (Microsoft, Redmond, WA, USA) are particularly suitable to achieve these aims because they are controlled by hand gestures and enable contactless handling in a sterile environment.

OBJECTIVES

So far, these systems have not yet found their way into the operating room for surgery of the parotid gland. This study explored the feasibility and accuracy of augmented reality-assisted parotid surgery.

METHODS

2D MRI holographic images were created, and 3D holograms were reconstructed from MRI DICOM files and made visible via the HoloLens. 2D MRI slices were scrolled through, 3D images were rotated, and 3D structures were shown and hidden only using hand gestures. The 3D model and the patient were aligned manually.

RESULTS

The use of augmented reality with the HoloLens in parotic surgery was feasible. Gestures were recognized correctly. Mean accuracy of superimposition of the holographic model and patient's anatomy was 1.3 cm. Highly significant differences were seen in position error of registration between central and peripheral structures (p = 0.0059), with a least deviation of 10.9 mm (centrally) and highest deviation for the peripheral parts (19.6-mm deviation).

CONCLUSION

This pilot study offers a first proof of concept of the clinical feasibility of the HoloLens for parotid tumor surgery. Workflow is not affected, but additional information is provided. The surgical performance could become safer through the navigation-like application of reality-fused 3D holograms, and it improves ergonomics without compromising sterility. Superimposition of the 3D holograms with the surgical field was possible, but further invention is necessary to improve the accuracy.