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Abstract: Optical properties (μa, μs and g) of certain human tissue types such as skin and blood have been very well investigated. However until today, for internal body organs such as the esophagus they are not well characterized. For ex‐vivo measurements “Inverse Adding Doubling” (IAD) and Inverse Monte‐Carlo‐Simulation (IMCS) are state of the art. Both methods need the measurement of the collimated transmission. Current methods lack a proper way of measuring the collimated transmission. Hence, this measurement of the g‐factor has a systematic error. Therefore, for the measurement of the collimated transmission, a new approach has been developed and evaluated with intralipid. Finally, the optical properties of mucosa, sub mucosa, muscularis and adventitia of pig esophagus tissue are calculated with IAD. The results are promising and in agreement with published literature. [ABSTRACT FROM AUTHOR]

In 28 patients supported by an Impella pump (Impella CP, Abiomed Inc. ® , Danvers, MA), hemodynamic measurements by PiCCO (PULSION Medical Systems SE ® , Feldkirchen, Germany) and pulmonary artery catheter (PAC or Swan-Ganz Catheter; Edwards Lifescience ® , Unterschleissheim, Germany) were compared. There was a significant positive correlation of cardiac output (CO; r 2  = 0.917, p  < 0.001), systemic vascular resistance index (SVRI; r 2  = 0.904, p  < 0.001), stroke volume index (SI; r 2  = 0.909, p  < 0.001) and left ventricular work index (LCWI; r 2  = 0.689, p  < 0.001) in PiCCO and PAC measurements under Impella CP support. We conclude, that in patients with left-ventricular Impella support, hemodynamics may be assessentd by PiCCO or PAC., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Intensive Care Society 2024.)

Background: The pulmonary artery wedge pressure (PAWP) is regarded as a reliable indicator of left ventricular end-diastolic pressure (LVEDP), but this association is weaker in patients with left-sided heart disease (LHD). We compared morphological differences in cardiac magnetic resonance imaging (CMR) in patients with heart failure (HF) and a reduced left ventricular ejection fraction (LVEF), with or without elevation of PAWP or LVEDP., Methods: We retrospectively identified 121 patients with LVEF < 50% who had undergone right heart catheterization (RHC) and CMR. LVEDP data were available for 75 patients., Results: The mean age of the study sample was 63 ± 14 years, the mean LVEF was 32 ± 10%, and 72% were men. About 53% of the patients had an elevated PAWP (>15 mmHg). In multivariable logistic regression analysis, NT-proBNP, left atrial ejection fraction (LAEF), and LV end-systolic volume index independently predicted an elevated PAWP. Of the 75 patients with available LVEDP data, 79% had an elevated LVEDP, and 70% had concomitant PAWP elevation. By contrast, all but one patient with elevated PAWP and half of the patients with normal PAWP had concomitant LVEDP elevation. The Bland-Altman plot revealed a systematic bias of +5.0 mmHg between LVEDP and PAWP. Notably, LAEF was the only CMR variable that differed significantly between patients with elevated LVEDP and a PAWP ≤ or >15 mmHg., Conclusions: In patients with LVEF < 50%, a normal PAWP did not reliably exclude LHD, and an elevated LVEDP was more frequent than an elevated PAWP. LAEF was the most relevant determinant of an increased PAWP, suggesting that a preserved LAEF in LHD may protect against backward failure into the lungs and the subsequent increase in pulmonary pressure.

Transthoracic and transesophageal echocardiography detected a left atrial mass attached to the intra-atrialseptum. Intravenous contrast agent ruled out atrial thrombus, sugesting a left atrial myxoma. This highlights theimportance of contrast echocardiography for differential diagnosis of left atrial findings., (© 2023. The Author(s).)

Background: To prevent complications, uncontrolled movement of the guidewire during a coronary intervention should be avoided. Unintentional withdrawal of the wire can result in the inability to recross a lesion with the risk of myocardial infarction. On the other hand, unintended forward pushing can lead to a coronary perforation. Thus, interventionalists in training should practice keeping the coronary guidewire in a stable position to prevent complications. For this purpose, a skill trainer has been developed, which provides the possibility of unlimited practice outside of the cath lab.The purpose of this study was to assess the effectiveness and the validity of this skills trainer., Methods: Ten novices and 10 participants with experience in diagnostic catheterization underwent training on the skills trainer consisting of 25 procedures. To assess the efficacy of the training module, the mean score of the first 3 procedures was compared with the final 3 procedures in the novice and the advanced group. To determine the construct validity of the simulator, a group of experts (E; performed >1000 percutaneous coronary interventions) also underwent evaluation on the skills trainer. For each procedure, the change in position of the guidewire as well as the time was determined and combined into a skills score with a maximum of 15 points., Results: The novice and the advanced group improved significantly throughout the training on the simulator (N: 7.1 ± 2.6 to 12.2 ± 2.0, P = 0.007; A: 8.3 ± 2.0 to 13.2 ± 1.0, P = 0.005, Wilcoxon).The experts scored significantly higher than novices or the advanced participants during their first 3 procedures (E: 12.9 ± 1.0; N: 7.1 ± 2.6, P = 0.001; A: 8.3 ± 2.0, P = 0.001; Mann-Whitney U )., Conclusions: This low-cost task trainer is a valid and effective tool to train adequate balloon/stent exchange while keeping the guidewire in a stable position. Whether the skills acquired on the task trainer can be transferred to procedures performed on patients needs further investigation., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Society for Simulation in Healthcare.)

Multi- and hyperspectral endoscopy are possibilities to improve the endoscopic detection of neoplastic lesions in the colon and rectum during colonoscopy. However, most studies in this context are performed on histological samples/biopsies or ex vivo. This leads to the question if previous results can be transferred to an in vivo setting. Therefore, the current study evaluated the usefulness of multispectral endoscopy in identifying neoplastic lesions in the colon. The data set consists of 25 mice with colonic neoplastic lesions and the data analysis is performed by machine learning. Another question addressed was whether adding additional spatial features based on Gauss-Laguerre polynomials leads to an improved detection rate. As a result, detection of neoplastic lesions was achieved with an MCC of 0.47. Therefore, the classification accuracy of multispectral colonoscopy is comparable with hyperspectral colonoscopy in the same spectral range when additional spatial features are used. Moreover, this paper strongly supports the current path towards the application of multi/hyperspectral endoscopy in clinical settings and shows that the challenges from transferring results from ex vivo to in vivo endoscopy can be solved., (© 2022. The Author(s).)

Despite TAVR emerging as the gold standard for a broad spectrum of patients, it is associated with serious complications. In this report we present a case, where a TAVR procedure led to a perforation at the aortomitral continuity, discuss the risk factors for the occurrence of perforations and how we decided to treat the patient., (© 2021 The Authors. Catheterization and Cardiovascular Interventions published by Wiley Periodicals LLC.)

The determination of the optical properties of a turbid medium is a major topic in the field of optics. Generally, they comprise the parameters µ a , µ s , g and n . There is, however, a lack of techniques for the direct determination of the scattering coefficient µ s . This study, therefore, proposes the random laser (RL) as a tool to directly measure µ s - and not μ s ' . Evidence is found that it is possible to determine µ s in the diffusive regime by means of the RL. Based on these findings, a local model of the RL is developed and presented in this study., Competing Interests: The authors declare no conflicts of interest., (© 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.)

Aims: Current European Society of Cardiology guidelines state that repetitive monitoring and feedback should be implemented for ST-elevation myocardial infarction (STEMI) treatment, but no evidence is available supporting this recommendation. We aimed to analyze the long-term effects of a formalized data assessment and systematic feedback on performance and mortality within the prospective, multicenter Feedback Intervention and Treatment Times in STEMI (FITT-STEMI) study., Methods: Regular interactive feedback sessions with local STEMI management teams were performed at six participating German percutaneous coronary intervention (PCI) centers over a 10-year period starting from October 2007., Results: From the first to the 10th year of study participation, all predefined key-quality indicators for performance measurement used for feedback improved significantly in all 4926 consecutive PCI-treated patients - namely, the percentages of patients with pre-hospital electrocardiogram (ECG) recordings (83.3% vs 97.1%, p < 0.0001) and ECG recordings within 10 minutes after first medical contact (41.7% vs 63.8%, p < 0.0001), pre-announcement by telephone (77.0% vs 85.4%, p = 0.0007), direct transfer to the catheterization laboratory bypassing the emergency department (29.4% vs 64.2%, p < 0.0001), and contact-to-balloon times of less than 90 minutes (37.2% vs 53.7%, p < 0.0001). Moreover, this feedback-related continuous improvement of key-quality indicators was linked to a significant reduction in in-hospital mortality from 10.8% to 6.8% ( p = 0.0244). Logistic regression models confirmed an independent beneficial effect of duration of study participation on hospital mortality (odds ratio = 0.986, 95% confidence interval = 0.976-0.996, p = 0.0087). In contrast, data from a nationwide PCI registry showed a continuous increase in in-hospital mortality in all PCI-treated STEMI patients in Germany from 2008 to 2015 ( n = 398,027; 6.7% to 9.2%, p < 0.0001)., Conclusions: Our results indicate that systematic data assessment and regular feedback is a feasible long-term strategy and may be linked to improved performance and a reduction in mortality in STEMI management., (© The European Society of Cardiology 2020.)

Objective: Treatment of symptomatic hyponatremia is not well established. The European guidelines recommend bolus-wise administration of 150 mL of 3% hypertonic saline. This recommendation is, however, based on low level of evidence., Design: Observational study., Methods: Sixty-two consecutive hyponatremic patients admitted to the emergency department or intensive care unit of the University Hospital Wuerzburg were divided in subgroups according to treatment (150 mL bolus of 3% hypertonic saline or conventional treatment) and symptom severity. Treatment target was defined as an increase in serum sodium by 5-10 mEq/L within first 24 h and maximum 8 mEq/L during subsequent 24 h., Results: Thirty-three out of sixty-two patients (53%) were presented with moderate symptoms and 29/62 (47%) with severe symptoms. Thirty-six were treated with hypertonic saline and 26 conventionally. In the hypertonic saline group, serum sodium increased from 116 ± 7 to 123 ± 6 (24 h) and 127 ± 6 mEq/L (48 h) and from 121 ± 6 to 126 ± 5 and 129 ± 4 mEq/L in the conventional group, respectively. Overcorrection at 24 h occurred more frequent in patients with severe symptoms than with moderate symptoms (38% vs 6%, P < 0.05). Diuresis correlated positively with the degree of sodium overcorrection at 24 h (r = 0.6, P < 0.01). Conventional therapies exposed patients to higher degrees of sodium fluctuations and an increased risk for insufficient sodium correction at 24 h compared to hypertonic saline (RR: 2.8, 95% CI: 1.4-5.5)., Conclusion: Sodium increase was more constant with hypertonic saline, but overcorrection rate was high, especially in severely symptomatic patients. Reducing bolus-volume and reevaluation before repeating bolus infusion might prevent overcorrection. Symptoms caused by hypovolemia can be misinterpreted as severely symptomatic hyponatremia and diuresis should be monitored.

Background: In patients with ST-segment elevation myocardial infarction (STEMI), it is unknown how patient delay modulates the beneficial effects of timely reperfusion., Aims: To assess the prognostic significance of a contact-to-balloon time of less than 90 min on in-hospital mortality in different categories of symptom-onset-to-first-medical-contact (S2C) times., Methods: A total of 20 005 consecutive patients from the Feedback Intervention and Treatment Times in ST-segment Elevation Myocardial Infarction (FITT-STEMI) programme treated with primary percutaneous coronary intervention (PCI) were included., Results: There were 1554 deaths (7.8%) with a J-shaped relationship between mortality and S2C time. Mortality was 10.0% in patients presenting within 1 hour, and 4.9%, 6.0% and 7.3% in patient groups with longer S2C intervals of 1-2 hours, 2-6 hours and 6-24 hours, respectively. Patients with a short S2C interval of less than 1 hour (S2C<60 min) had the highest survival benefit from timely reperfusion with PCI within 90 min (OR 0.27, 95% CI 0.23 to 0.31, p<0.0001) as compared with the three groups with longer S2C intervals of 1 hour

In medical applications, hyper-spectral imaging is becoming more and more common. It has been shown to be more effective for classification and segmentation than normal RGB imaging because narrower wavelength bands are used, providing a higher contrast. However, until now, the fact that hyper-spectral images also contain information about the three-dimensional structure of turbid media has been neglected. In this study, it is shown that it is possible to derive information about the depth of inclusions in turbid phantoms from a single hyper-spectral image. Here, the depth information is encoded by a combination of scattering and absorption within the phantom. Although scatter-dominated regions increase the backscattering for deep vessels, absorption has the opposite effect. With this argumentation, it makes sense to assume that, under certain conditions, a wavelength is not influenced by the depth of the inclusion and acts as an iso-point. This iso-point could be used to easily derive information about the depth of an inclusion. In this study, it is shown that the iso-point exists in some cases. Moreover, it is shown that the iso-point can be used to obtain precise depth information.

Multiple diseases are associated with a wide spectrum of microvascular dysfunctions, microangiopathies and microcirculation disorders. Monitoring the microcirculation could thus be useful to diagnose many local and systemic circulatory disorders and to supervise critically ill patients. Many of the scores currently available to help identify the condition of a microcirculation disorder are invasive or leave scope for interpretation. Thus, the present study aims to investigate with Monte-Carlo simulations (as numerical solutions of the radiative transfer equation) whether shifted position-diffuse reflectance imaging (SP-DRI), a non-invasive diagnostic technique, reveals information on the capillary diameter to assess the state of the microcirculation. To quantify the SP-DRI signal, the modulation parameter K is introduced. It proves to correlate almost perfectly with the capillary diameter ( R ¯ 2 ≈ 1 ), making it a valid parameter for reliably assessing microcirculation. SP-DRI is emerging as an important milestone on the way to early and conveniently diagnosing microcirculation associated diseases., (© 2021 The Authors. Journal of Biophotonics published by Wiley-VCH GmbH.)

The need for tissue contact makes photoacoustic imaging not applicable for special medical applications like wound imaging, endoscopy, or laser surgery. An easy, stable, and contact-free sensing technique might thus help to broaden the applications of the medical imaging modality. In this work, it is demonstrated for the first time that remote photoacoustic sensing by speckle analysis can be performed in the MHz sampling range by tracking a single speckle using a four quadrant photo-detector. A single speckle, which is created by self-interference of surface back-reflection, is temporally analyzed using this photo-detector. Phantoms and skin samples are measured in transmission and reflection mode. The potential for miniaturization for endoscopic application is demonstrated by fiber bundle measurements. In addition, sensing parameters are discussed. Photoacoustic sensing in the MHz sampling range by single speckle analysis with the four quadrant detector is successfully demonstrated. Furthermore, the endoscopic applicability is proven, and the sensing parameters are convenient for photoacoustic sensing. It can be concluded that a single speckle contains all the relevant information for remote photoacoustic signal detection. Single speckle sensing is therefore an easy, robust, contact-free photoacoustic detection technique and holds the potential for economical, ultra-fast photoacoustic sensing. The new detection technique might thus help to broaden the field of photoacoustic imaging applications in the future.

Background: Cardiac arrhythmias are a serious complication in patients admitted due to intoxication in suicidal attempts. Upon admission, detailed information about the specific kind of intoxication are frequently missing. The differential diagnoses of electrocardiogram (ECG) changes such as elevation of T-waves, prolongation of the QT-interval or elevation of ST-segments in this special subgroup of patients comprise drug-induced electrolyte disorders or direct toxic effects on cardiac excitation and repolarization., Case Summary: In this clinical report of a 27-year-old male patient, we present a case of unusual ECG alterations mimicking ST-elevation, high amplitude, biphasic T-waves and prolongation of QT-interval. These changes of surface ECG were induced by ingestion of cylindrical batteries in a suicidal attempt and immediately normalized after removal of batteries by esophagogastroduodenoscopy., Discussion: There is limited literature describing changes in surface ECG in patients having ingested cylindrical batteries. We propose two hypotheses for the occurrence of these changes after ingestion of cylindrical batteries: (i) Cardiac movement within the perturbation field induced by the batteries causes electrical changes on a time scale of the heart rate which are above the threshold of the high pass filter. (ii) The batteries' electrotonic potential affects the membrane currents of cardiac myocytes, not inducing an action potential but generating repolarization abnormalities. Individual factors, such as body constitution and localization of the batteries within the stomach, determine the interindividual characteristics of repolarization abnormalities., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Society of Cardiology.)

In general, the measurement of the main three optical properties ( µ a , µ s and g ) in turbid media requires a very precise measurement of the total transmission (TT), the total reflection (TR) and the collimated transmission (CT). Furthermore, an inverse algorithm such as inverse adding doubling or inverse Monte-Carlo-simulations is required for the reconstruction of the optical properties. Despite many available methods, the error free measurement of the scattering coefficient or the g-factor still remains challenging. In this study, we present a way to directly calculate the scattering coefficient from the total and collimated transmission. To allow this, it can be shown that T T C T is proportional to e μ s ⋅ d for a wide range of optical properties if the sample is thick enough. Moreover, a set-up is developed and validated to measure the collimated transmission precisely., Competing Interests: The authors declare no competing interests., (© 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.)

Aims: To assess the impact of the lockdown due to coronavirus disease 2019 (COVID-19) on key quality indicators for the treatment of ST-segment elevation myocardial infarction (STEMI) patients., Methods: Data were obtained from 41 hospitals participating in the prospective Feedback Intervention and Treatment Times in ST-Elevation Myocardial Infarction (FITT-STEMI) study, including 15,800 patients treated for acute STEMI from January 2017 to the end of March 2020., Results: There was a 12.6% decrease in the total number of STEMI patients treated at the peak of the pandemic in March 2020 as compared to the mean number treated in the March months of the preceding years. This was accompanied by a significant difference among the modes of admission to hospitals (p = 0.017) with a particular decline in intra-hospital infarctions and transfer patients from other hospitals, while the proportion of patients transported by emergency medical service (EMS) remained stable. In EMS-transported patients, predefined quality indicators, such as percentages of pre-hospital ECGs (both 97%, 95% CI = - 2.2-2.7, p = 0.846), direct transports from the scene to the catheterization laboratory bypassing the emergency department (68% vs. 66%, 95% CI = - 4.9-7.9, p = 0.641), and contact-to-balloon-times of less than or equal to 90 min (58.3% vs. 57.8%, 95%CI = - 6.2-7.2, p = 0.879) were not significantly altered during the COVID-19 crisis, as was in-hospital mortality (9.2% vs. 8.5%, 95% CI = - 3.2-4.5, p = 0.739)., Conclusions: Clinically important indicators for STEMI management were unaffected at the peak of COVID-19, suggesting that the pre-existing logistic structure in the regional STEMI networks preserved high-quality standards even when challenged by a threatening pandemic., Clinical Trial Registration: NCT00794001.

Due to significant advantages, the trend in the field of medical technology is moving towards minimally or even non-invasive examination methods. In this respect, optical methods offer inherent benefits, as does diffuse reflectance imaging (DRI). The present study attempts to prove the suitability of DRI-when implemented alongside a suitable setup and data evaluation algorithm-to derive information from anatomically correctly scaled human capillaries (diameter: [Formula: see text], length: [Formula: see text]) by conducting extensive Monte-Carlo simulations and by verifying the findings through laboratory experiments. As a result, the method of shifted position-diffuse reflectance imaging (SP-DRI) is established by which average signal modulations of up to 5% could be generated with an illumination wavelength of [Formula: see text] and a core diameter of the illumination fiber of [Formula: see text]. No reference image is needed for this technique. The present study reveals that the diffuse reflectance data in combination with the SP-DRI normalization are suitable to localize human capillaries within turbid media.

Photoacoustic endoscopy (PAE) is a method of in-vivo imaging that uses tissue absorption properties. In PAE, the main tools used to detect the acoustic signal are mechanical ultrasound transducers, which require direct contact and which are difficult to miniaturize. All-optic photoacoustic sensors can challenge this issue as they can provide contact-free sensing. Here, we demonstrate sensing of photo-acoustic signals through a multimode fiber (MMF) which can provide an ultra-thin endoscopic photoacoustic sensor. Furthermore, we show the advantage of using the optical-flow method for speckle sensing and extract the photoacoustic signal despite the mode-mixing along the MMF. Moreover, it is demonstrated for the first time that the speckle reconstruction method can be used without the need for imaging of the speckles as this enables the use of multimode fibers for the speckle method.

Background: In ST-segment elevation myocardial infarction (STEMI) patients treated with percutaneous coronary intervention, direct transport from the scene to the catheterisation laboratory bypassing the emergency department has been shown to shorten times to reperfusion. The aim of this study was to investigate the effects of emergency department bypass on mortality in both haemodynamically stable and unstable STEMI patients., Methods: The analysis is based on a large cohort of STEMI patients prospectively included in the German multicentre Feedback Intervention and Treatment Times in ST-Elevation Myocardial Infarction (FITT-STEMI) trial., Results: Out of 13,219 STEMI patients who were brought directly from the scene by emergency medical service transportation and were treated with percutaneous coronary intervention, the majority were transported directly to the catheterisation laboratory bypassing the emergency department ( n =6740, 51% with emergency department bypass). These patients had a significantly lower in-hospital mortality than their counterparts with no emergency department bypass (6.2% vs. 10.0%, P <0.0001). The reduced mortality related to emergency department bypass was observed in both stable ( n =11,594, 2.8% vs. 3.8%, P =0.0024) and unstable patients presenting with cardiogenic shock ( n =1625, 36.3% vs. 46.2%, P <0.0001). Regression models adjusted for the Thrombolysis In Myocardial Infarction (TIMI) risk score consistently confirmed a significant and independent predictive effect of emergency department bypass on survival in the total study population (odds ratio 0.64, 95% confidence interval 0.56-0.74, P <0.0001) and in the subgroup of shock patients (OR 0.69, 95% CI 0.54-0.88, P =0.0028)., Conclusion: In STEMI patients, emergency department bypass is associated with a significant reduction in mortality, which is most pronounced in patients presenting with cardiogenic shock. Our data encourage treatment protocols for emergency department bypass to improve the survival of both haemodynamically stable patients and, in particular, unstable patients. Clinical Trial Registration: NCT00794001 ClinicalTrials.gov: NCT00794001.

Hyper spectral imaging is a possible way for disease detection. However, for carcinoma detection most of the results are ex-vivo. However, in-vivo results of endoscopic studies still show fairly low accuracies in contrast to the good results of many ex-vivo studies. To overcome this problem and to provide a reasonable explanation, Monte-Carlo simulations of photon trajectories are proposed as a tool to generate multi spectral images including inter patient variations to simulate 40 patients. Furthermore, these simulations have the huge advantage that the position of the carcinoma is known. Due to this, the effect of mislabelled data can be studied. As shown in this study, a percentage of 30-35% of mislabelled data might lead to significant decrease of the accuracy from around 90% to around 70-75%. Therefore, the main focus of hyper spectral imaging has to be the exact characterization of the training data in the future.