Klinik und Poliklinik für Hals-, Nasen- und Ohrenkrankheiten, plastische und ästhetische Operationen
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- cochlear implant (11)
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- Klinik und Poliklinik für Hals-, Nasen- und Ohrenkrankheiten, plastische und ästhetische Operationen (252)
- Graduate School of Life Sciences (8)
- Institut für diagnostische und interventionelle Neuroradiologie (ehem. Abteilung für Neuroradiologie) (6)
- Lehrstuhl für Tissue Engineering und Regenerative Medizin (5)
- Klinik und Poliklinik für Strahlentherapie (4)
- Pathologisches Institut (4)
- Institut für Humangenetik (2)
- Klinik und Poliklinik für Nuklearmedizin (2)
- Medizinische Klinik und Poliklinik I (2)
- Neurologische Klinik und Poliklinik (2)
Sonstige beteiligte Institutionen
Purpose
While [\(^{18}\)F]-fluorodeoxyglucose ([\(^{18}\)F]FDG) is the standard for positron emission tomography/computed tomography (PET/CT) imaging of oral squamous cell carcinoma (OSCC), diagnostic specificity is hampered by uptake in inflammatory cells such as neutrophils or macrophages. Recently, molecular imaging probes targeting fibroblast activation protein α (FAP), which is overexpressed in a variety of cancer-associated fibroblasts, have become available and might constitute a feasible alternative to FDG PET/CT.
Methods
Ten consecutive, treatment-naïve patients (8 males, 2 females; mean age, 62 ± 9 years) with biopsy-proven OSCC underwent both whole-body [\(^{18}\)F]FDG and [\(^{68}\)Ga]FAPI-04 (FAP-directed) PET/CT for primary staging prior to tumor resection and cervical lymph node dissection. Detection of the primary tumor, as well as the presence and number of lymph node and distant metastases was analysed. Intensity of tracer accumulation was assessed by means of maximum (SUV\(_{max}\)) and peak (SUV\(_{peak}\) standardized uptake values. Histological work-up including immunohistochemical staining for FAP served as standard of reference.
Results
[\(^{18}\)F]FDG and FAP-directed PET/CT detected all primary tumors with a SUVmax of 25.5 ± 13.2 (FDG) and 20.5 ± 6.4 (FAP-directed) and a SUVpeak of 16.1 ± 10.3 ([\(^{18}\)F]FDG) and 13.8 ± 3.9 (FAP-directed), respectively. Regarding cervical lymph node metastases, FAP-directed PET/CT demonstrated comparable sensitivity (81.3% vs. 87.5%; P = 0.32) and specificity (93.3% vs. 81.3%; P = 0.16) to [\(^{18}\)F]FDG PET/CT. FAP expression on the cell surface of cancer-associated fibroblasts in both primary lesions as well as lymph nodes metastases was confirmed in all samples.
Conclusion
FAP-directed PET/CT in OSCC seems feasible. Future research to investigate its potential to improve patient staging is highly warranted.
Background: The benefit of hearing rehabilitation is often measured using audiological tests or subjective questionnaires/interviews. It is important to consider both aspects in order to evaluate the overall benefits. Currently, there is no standardized method for reporting combined audiological and patient reported subjective outcome measures in clinical practice. Therefore, this study focuses on showing the patient’s audiological, as well as subjective outcomes in one graph using data from an existing study. Method: The present paper illustrated a graph presenting data on four quadrants with audiological and subjective findings. These quadrants represented speech comprehension in quiet (unaided vs. aided) as WRS% at 65 dB SPL, speech recognition in noise (unaided vs. aided) as SRT dB SNR, sound field threshold (unaided vs. aided) as PTA\(_4\) in dB HL, wearing time and patient satisfaction questionnaire results. Results: As an example, the HEARRING graph in this paper represented audiological and subjective datasets on a single patient level or a cohort of patients for an active bone conduction hearing implant solution. The graph offered the option to follow the user’s performance in time. Conclusion: The HEARRING graph allowed representation of a combination of audiological measures with patient reported outcomes in one single graph, indicating the overall benefit of the intervention. In addition, the correlation and consistency between some results (e.g., aided threshold and aided WRS) can be better visualized. Those users who lacked performance benefits on one or more parameters and called for further insight could be visually identified.
Different effects of conditional Knock-Out of Stat3 on the sensory epithelium of the Organ of Corti
(2024)
The mammalian cochlea detects sound in response to vibration at frequency-dependent positions along the cochlea duct. The sensory outer hair cells, which are surrounded by supporting cells, act as a signal amplifier by changing their cell length. This is called electromotility. To ensure correct electrical transmission during mechanical forces, a certain resistance of the sensory epithelium is a prerequisite for correct transduction of auditory information. This resistance is managed by microtubules and its posttranslational modification in the supporting cells of the sensory epithelium of the cochlea. Stat3 is a transcription factor, with its different phosphorylation sites, is involved in many cellular processes like differentiation, inflammation, cell survival and microtubule dynamics, depending on cell type and activated pathway. While Stat3 has a wide range of intracellular roles, the question arose, how and if Stat3 is involved in cells of the organ of Corti to ensure a correct hearing.
To test this, Cre/loxp system were used to perform conditional Knock-Out (cKO) of Stat3 in outer hair cells or supporting cells either before hearing onset or after hearing onset. Hearing performances included DPOAE and ABR measurements, while molecular were performed by sequencing. Additionally, morphological examination was used by immunohistochemistry and electron microscopy.
A cKO of Stat3 before and after hearing onset in outer hair cells leads to hearing impairments, whereas synapses, nerve fibers and mitochondria were not affected. Bulk sequencing analyzation of outer hair cells out of cKO mice before hearing onset resulted in a disturbance of cellular homeostasis and extracellular signals. A cKO of Stat3 in the outer hair cells after hearing onset resulted in inflammatory signaling pathway with increased cytokine production and upregulation of NF-kb pathway. In supporting cells, cKO of Stat3 only after hearing onset resulted in a hearing impairment. However, synapses, nerve soma and fibers were not affected of a cKO of Stat3 in supporting cells. Nevertheless, detyronisated modification of microtubules were altered, which can lead to an instability of supporting cells during hearing.
In conclusion, Stat3 likely interact in a cell-specific and function-specific manner in cells of the organ of Corti. While a cKO in outer hair cells resulted in increased cytokine production, supporting cells altered its stability due to decreased detyronisated modification of microtubules. Together the results indicated that Stat3 is an important protein for hearing performances. However, additional investigations of the molecular mechanism are needed to understand the role of Stat3 in the cells of the organ of Corti.
Background
Eye movement abnormalities are commonplace in neurological disorders. However, unaided eye movement assessments lack granularity. Although videooculography (VOG) improves diagnostic accuracy, resource intensiveness precludes its broad use. To bridge this care gap, we here validate a framework for smartphone video-based nystagmography capitalizing on recent computer vision advances.
Methods
A convolutional neural network was fine-tuned for pupil tracking using > 550 annotated frames: ConVNG. In a cross-sectional approach, slow-phase velocity of optokinetic nystagmus was calculated in 10 subjects using ConVNG and VOG. Equivalence of accuracy and precision was assessed using the “two one-sample t-test” (TOST) and Bayesian interval-null approaches. ConVNG was systematically compared to OpenFace and MediaPipe as computer vision (CV) benchmarks for gaze estimation.
Results
ConVNG tracking accuracy reached 9–15% of an average pupil diameter. In a fully independent clinical video dataset, ConVNG robustly detected pupil keypoints (median prediction confidence 0.85). SPV measurement accuracy was equivalent to VOG (TOST p < 0.017; Bayes factors (BF) > 24). ConVNG, but not MediaPipe, achieved equivalence to VOG in all SPV calculations. Median precision was 0.30°/s for ConVNG, 0.7°/s for MediaPipe and 0.12°/s for VOG. ConVNG precision was significantly higher than MediaPipe in vertical planes, but both algorithms’ precision was inferior to VOG.
Conclusions
ConVNG enables offline smartphone video nystagmography with an accuracy comparable to VOG and significantly higher precision than MediaPipe, a benchmark computer vision application for gaze estimation. This serves as a blueprint for highly accessible tools with potential to accelerate progress toward precise and personalized Medicine.
Die Maus mit progressiver motorischer Neuropathie (PMN) ist ein Modell für eine vererbte motorische Neuropathie mit progressiver Neurodegeneration. Die Degeneration der Axone geht mit homozygoten Mutationen des TBCE- Gens einher, das für das Tubulin-Chaperon-E- Protein kodiert. TBCE ist für die korrekte Dimerisierung von Alpha- und Beta-Tubulin verantwortlich. Auffallend ist, dass die PMN-Maus nach dem normalen Beginn des Hörens auch einen progressiven Hörverlust entwickelt, der durch die Degeneration des Hörnervs und den Verlust der äußeren Haarzellen (OHC) gekennzeichnet ist. Die Entwicklung dieser neuronalen und cochleären Pathologie ist
Wirkung von peg-IGF-1 auf das auditorische System durch Behandlung ab dem 15. postnatalen Tag (p15). Die histologische Analyse ergab positive Auswirkungen auf die OHC-Synapsen der medialen olivocochleären (MOC) neuronalen Fasern und eine kurzfristige Abschwächung des OHC-Verlustes. Peg-IGF-1 war in der Lage, die Desorganisation der OHC-Synapsen bedingt wiederherzustellen und die Bereitstellung von cholinerger Acetyltransferase in den Präsynapsen aufrechtzuerhalten. Zur Beurteilung der auditorischen Funktion wurden frequenzspezifische Hirnstammreaktionen und otoakustische Emissionen mit Verzerrungsprodukten bei Tieren mit p21 und p28 aufgezeichnet. Trotz der positiven Auswirkungen auf die MOC-Fasern und die OHC konnte jedoch keine Wiederherstellung des Hörvermögens erreicht werden. Die vorliegende Arbeit zeigt, dass die synaptische Pathologie der efferenten MOC-Fasern in PMN-Mäusen eine besondere Form der "efferenten auditorischen Neuropathie" darstellt. Peg-IGF-1 zeigte eine otoprotektive Wirkung, indem es die Degeneration von OHCs und efferenten Synapsen verhinderte. Es sind jedoch verstärkte Anstrengungen zur Optimierung der Behandlung erforderlich, um nachweisbare Verbesserungen der Hörleistung zu erzielen.
The medial geniculate body (MGB) is a nucleus of the diencephalon representing a relevant segment of the auditory pathway and is part of the metathalamus. It receives afferent information via the inferior brachium of the inferior colliculus and transmits efferent fibers via acoustic radiations to the auditory cortex. Neural stem cells (NSCs) have been detected in certain areas along the auditory pathway. They are of great importance as the induction of an adult stem cell niche might open a regenerative approach to a causal treatment of hearing disorders. Up to now, the existence of NSCs in the MGB has not been determined. Therefore, this study investigated whether the MGB has a neural stem cell potential. For this purpose, cells were extracted from the MGB of PND 8 Sprague-Dawley rats and cultured in a free-floating cell culture assay, which showed mitotic activity and positive staining for stem cell and progenitor markers. In differentiation assays, the markers β-III-tubulin, GFAP, and MBP demonstrated the capacity of single cells to differentiate into neuronal and glial cells. In conclusion, cells from the MGB exhibited the cardinal features of NSCs: self-renewal, the formation of progenitor cells, and differentiation into all neuronal lineage cells. These findings may contribute to a better understanding of the development of the auditory pathway.
Due to the wide variety of benign and malignant salivary gland tumors, classification and malignant behavior determination based on histomorphological criteria can be difficult and sometimes impossible. Spectroscopical procedures can acquire molecular biological information without destroying the tissue within the measurement processes. Since several tissue preparation procedures exist, our study investigated the impact of these preparations on the chemical composition of healthy and tumorous salivary gland tissue by Fourier-transform infrared (FTIR) microspectroscopy. Sequential tissue cross-sections were prepared from native, formalin-fixed and formalin-fixed paraffin-embedded (FFPE) tissue and analyzed. The FFPE cross-sections were dewaxed and remeasured. By using principal component analysis (PCA) combined with a discriminant analysis (DA), robust models for the distinction of sample preparations were built individually for each parotid tissue type. As a result, the PCA-DA model evaluation showed a high similarity between native and formalin-fixed tissues based on their chemical composition. Thus, formalin-fixed tissues are highly representative of the native samples and facilitate a transfer from scientific laboratory analysis into the clinical routine due to their robust nature. Furthermore, the dewaxing of the cross-sections entails the loss of molecular information. Our study successfully demonstrated how FTIR microspectroscopy can be used as a powerful tool within existing clinical workflows.
Purpose
Surgery is a standard therapy for tympanojugular paragangliomas (TJP). Maintaining the quality of life (QoL) requires functional preservation. The flexible CO\(_2\) laser allows contact-free tumor removal. This retrospective study compares the postoperative functional outcomes of TJP surgery with and without the flexible CO\(_2\) laser.
Methods
Between 2005 and 2019, 51 patients with TJP were surgically treated at a tertiary hospital. Until 2012, 17 patients received conventional surgery. Thereafter, the flexible laser was used in 34 patients. Tumor extend, pre- and postoperative cranial nerve function, and complications were compared between the groups.
Results
The cohort consisted of 33 class A and B tumors and 18 class C and D tumors. Preoperative embolization was performed in 17 cases. Class C/D TJP were usually removed via an infratemporal fossa type A approach. Gross total tumor removal was achieved in 14/18 class C/D tumors. 3/51 patients suffered from long-term partial or complete facial palsy. No differences in post-therapeutic cranial nerve function or complications were noted between the conventional and laser group. One recurrence was observed after complete tumor resection.
Conclusion
The flexible CO\(_2\) laser was shown to be a safe and effective alternative to conventional bipolar cauterization, which is appreciated by the surgeon in these highly vascularized tumors. Both techniques allowed a high tumor control rate and good long-term results also from a functional point of view.
Surgical management of lateral neck abscesses in children: a retrospective analysis of 100 cases
(2023)
Cervical abscesses are relatively common infections in pediatric patients. There is an ongoing debate about the necessity and time point of surgical drainage. The identification of a focus of infection might play an important role in facilitating a therapeutic decision. In a retrospective study, 100 pediatric patients aged 1–18 years who underwent incision and drainage of a lateral cervical abscess at our institution were analyzed. Patients were divided into two groups based on whether a focus of infection could be identified or not. Data collection included patient characteristics, microbiological results, antibiotic regimen, and clinical course. A focus of infection was found in 29% (29/100) of the patients, most frequently in the tonsils. A causative microorganism was found in 75% (75/100) of all patients, with Staphylococcus aureus and Streptococcus pyogenes being the most common pathogens. All patients received an empiric antibiotic therapy in addition to surgery. Antibiotic medication was changed in 31% in both groups (9/29 with a focus of infection and 22/71 without a focus of infection) during therapy. Children without an identified focus of infection generally were younger and had more comorbidities reducing immune response while also showing differences in the pathogens involved. There were no complications associated to surgery or antibiotic therapy in any of the patients involved.
Conclusion: Children with an identified focus of infection show several differences compared to those with isolated lateral abscesses, especially regarding the microorganisms involved. But the focus of infection seems not to have an impact on patient’s outcome.
What is Known:
• Neck abscesses are a relatively common disease in the pediatric population and may cause serious complications.
• Therapy in general consists of intravenous antibiotics with or without surgery.
What is New:
• The focus identification has no impact on patient’s outcome.
• Children with an identified focus of infection show several differences compared to those with isolated lateral abscesses, especially regarding their medical history, age, and the microorganisms involved.
Towards a consensus on an ICF-based classification system for horizontal sound-source localization
(2022)
The study aimed to develop a consensus classification system for the reporting of sound localization testing results, especially in the field of cochlear implantation. Against the background of an overview of the wide variations present in localization testing procedures and reporting metrics, a novel classification system was proposed to report localization errors according to the widely accepted International Classification of Functioning, Disability and Health (ICF) framework. The obtained HEARRING_LOC_ICF scale includes the ICF graded scale: 0 (no impairment), 1 (mild impairment), 2 (moderate impairment), 3 (severe impairment), and 4 (complete impairment). Improvement of comparability of localization results across institutes, localization testing setups, and listeners was demonstrated by applying the classification system retrospectively to data obtained from cohorts of normal-hearing and cochlear implant listeners at our institutes. The application of our classification system will help to facilitate multi-center studies, as well as allowing better meta-analyses of data, resulting in improved evidence-based practice in the field.