Features of Mild-to-Moderate COVID-19 Patients with Dysphonia

Introduction To explore the prevalence of dysphonia in European patients with mild-to-moderate COVID-19 and the clinical features of dysphonic patients. Methods The clinical and epidemiological data of 702 patients with mild-to-moderate COVID-19 were collected from 19 European Hospitals. The following data were extracted: age, sex, ethnicity, tobacco consumption, comorbidities, general and otolaryngological symptoms. Dysphonia and otolaryngological symptoms were self-assessed through a 4-point scale. The prevalence of dysphonia, as part of the COVID-19 symptoms, was assessed. The outcomes were compared between dysphonic and non-dysphonic patients. The association between dysphonia severity and outcomes was studied through Bayesian analysis. Results A total of 188 patients were dysphonic, accounting for 26.8% of cases. Females developed more frequently dysphonia than males (p=0.022). The proportion of smokers was significantly higher in the dysphonic group (p=0.042). The prevalence of the following symptoms was higher in dysphonic patients compared with non-dysphonic patients: cough, chest pain, sticky sputum, arthralgia, diarrhea, headache, fatigue, nausea and vomiting. The severity of dyspnea, dysphagia, ear pain, face pain, throat pain and nasal obstruction was higher in dysphonic group compared with non-dysphonic group. There were significant associations between the severity of dysphonia, dysphagia and cough. Conclusion Dysphonia may be encountered in a quarter of patients with mild-to-moderate COVID-19 and should be considered as a symptom list of the infection. Dysphonic COVID-19 patients are more symptomatic than non-dysphonic individuals. Future studies are needed to investigate the relevance of dysphonia in the COVID-19 clinical presentation

High-resolution optoacoustic mesoscopy with a 24 MHz multidetector translate-rotate scanner.

Optoacoustic (photoacoustic) mesoscopy aims at high-resolution optical imaging of anatomical, functional, and cellular parameters at depths that go well beyond those of optical-resolution optical or optoacoustic microscopy i.e., reaching several millimeters in depth. The approach utilizes tomography to achieve ultrasonic-diffraction resolution and operates at high-ultrasound frequencies (20 to 200 MHz) induced by few-nanosecond laser pulse excitation of tissues. We investigated here the performance of optoacoustic mesoscopy implemented at 24 MHz center frequency and its ability to resolve optical absorption contrast in the mouse kidney ex vivo. The developed system achieved better than 30 μm in-plane resolution and 110 μm elevation resolution over a cylindrical volume of 9-mm diameter and 9-mm height. This unprecedented combination of resolution and depth was achieved by implementing a translate-rotate detection geometry and by tomographic reconstruction. The approach yielded images of optically absorbing structures with a level of detail never-before visualized in an intact mouse kidney and allows insights into their unperturbed architecture. We discuss the ability to offer multispectral acquisitions and enable in vivo imaging

Ultra-wideband three-dimensional optoacoustic tomography.

Broadband optoacoustic waves generated by biological tissues excited with nanosecond laser pulses carry information corresponding to a wide range of geometrical scales. Typically, the frequency content present in the signals generated during optoacoustic imaging is much larger compared to the frequency band captured by common ultrasonic detectors, the latter typically acting as bandpass filters. To image optical absorption within structures ranging from entire organs to microvasculature in three dimensions, we implemented optoacoustic tomography with two ultrasound linear arrays featuring a center frequency of 6 and 24 MHz, respectively. In the present work, we show that complementary information on anatomical features could be retrieved and provide a better understanding on the localization of structures in the general anatomy by analyzing multi-bandwidth datasets acquired on a freshly excised kidney

Multiple bandwidth volumetric optoacoustic tomography using conventional ultrasound linear arrays.

In optoacoustic imaging absorbing structures excited with short laser pulses generate broadband ultrasound waves, which tomographically detected outside the sample enable reconstruction of initial pressure distribution. As light scatters in biological tissues, the excitation has a three-dimensional (3D) pattern allocation. Accurate reconstruction of the 3D distribution of optical absorption requires a large solid angle of detection of the ultrasonic field. Moreover, the center frequency and bandwidth of a given detector define the range of structure sizes it is able to resolve. Therefore, detectors with different frequency bandwidths record different subsets of information. A volumetric optoacoustic system using linear ultrasound arrays with different central frequencies, 6MHz and 24MHz, is introduced. By employing a novel scanning geometry that takes advantage of the high sensitivity on the transversal dimension of these linear probes, high resolution optoacoustic signals are being recorded. Resolution performance and biological capabilities are demonstrated with a 20um crossed-suture phantom and an excised mouse liver lobe

Tumorsegmentierung in CD3/CD8-gefärbten Histopathologien

Segmentierung von bestimmten Gewebetypen in Histopathologien ist eine oft untersuchte Fragestellung. Üblicherweise werden dafür Gewebeproben mit Hämatoxylin-Eosin(HE)-Färbung verwendet. CD3/CD8-Färbungen hingegen sind nötig zur Sichtbarmachung von Immunzellen, differenzieren aber nur wenig zwischen unterschiedlichen Gewebearten. Vorteilhaft wäre es, wenn aus nur einem Gewebeschnitt mit einer bestimmten Färbung beide Informationen extrahiert werden könnten. In dieser Arbeit stellen wir ein Segmentierungsverfahren auf CD3/CD8-gefärbten Gewebeproben vor, das effizient zu berechnende und gleichzeitig aussagekräftige Features als Eingabe für einen Clustering- Algorithmus verwendet. In der Evaluation wird ein durchschnittlicher Accuracy-Wert von 94,44% erzielt. Dieser Wert ist vergleichbar mit den Ergebnissen verwandter State of the Art Methoden, die HE-gefärbte Proben einsetzen

Sensitive interferometric detection of ultrasound for minimally invasive clinical imaging applications.

Miniaturized optical detectors of ultrasound represent a promising alternative to piezoelectric technology and may enable new minimally invasive clinical applications, particularly in the field of optoacoustic imaging. However, the use of such detectors has so far been limited to controlled lab environments, and has not been demonstrated in the presence of mechanical disturbances, common in clinical imaging scenarios. Additionally, detection sensitivity has been inherently limited by laser noise, which hindered the use of sensing elements such as optical fibers, which exhibit a weak response to ultrasound. In this work, coherence-restored pulse interferometry (CRPI) is introduced – a new paradigm for interferometric sensing in which shot-noise limited sensitivity may be achieved alongside robust operation. CRPI is implemented with a fiber-based resonator, demonstrating over an order of magnitude higher sensitivity than that of conventional 15 MHz intravascular ultrasound probes. The performance of the optical detector is showcased in a miniaturized all-optical optoacoustic imaging catheter

Optical mesoscopy without the scatter: Broadband multispectral optoacoustic mesoscopy.

Optical mesoscopy extends the capabilities of biological visualization beyond the limited penetration depth achieved by microscopy. However, imaging of opaque organisms or tissues larger than a few hundred micrometers requires invasive tissue sectioning or chemical treatment of the specimen for clearing photon scattering, an invasive process that is regardless limited with depth. We developed previously unreported broadband optoacoustic mesoscopy as a tomographic modality to enable imaging of optical contrast through several millimeters of tissue, without the need for chemical treatment of tissues. We show that the unique combination of three-dimensional projections over a broad 500 kHz-40 MHz frequency range combined with multi-wavelength illumination is necessary to render broadband multispectral optoacoustic mesoscopy (2B-MSOM) superior to previous optical or optoacoustic mesoscopy implementations

Three-dimensional optoacoustic mesoscopy of the tumor heterogeneity in <em>vivo</em> using high depth-to-resolution multispectral optoacoustic tomography.

Multispectral optoacoustic mesoscopy (MSOM) has been recently introduced for cancer imaging, it has the potential for high resolution imaging of cancer development in vivo, at depths beyond the diffusion limit. Based on spectral features, optoacoustic imaging is capable of visualizing angiogenesis and imaging cancer heterogeneity of malignant tumors through endogenous hemoglobin. However, high-resolution structural and functional imaging of whole tumor mass is limited by modest penetration and image quality, due to the insufficient capability of ultrasound detectors and the twodimensional scan geometry. In this study, we introduce a novel multi-spectral optoacoustic mesoscopy (MSOM) for imaging subcutaneous or orthotopic tumors implanted in lab mice, with the high-frequency ultrasound linear array and a conical scanning geometry. Detailed volumetric images of vasculature and oxygen saturation of tissue in the entire tumors are obtained in vivo, at depths up to 10 mm with the desirable spatial resolutions approaching 70&mu;m. This unprecedented performance enables the visualization of vasculature morphology and hypoxia conditions has been verified with ex vivo studies. These findings demonstrate the potential of MSOM for preclinical oncological studies in deep solid tumors to facilitate the characterization of tumor&rsquo;s angiogenesis and the evaluation of treatment strategies