Noninvasive Visualization of the Tear Film Microaerosol During Noncontact Tonometry Measurements.

PURPOSE: To investigate the aerosol generation by a noninvasive real-time observation device and assess the conditions relating to aerosolization during intraocular pressure (IOP) measurements using a commercial noncontact tonometer (NCT). STUDY DESIGN: Prospective experimental and healthy eye studies. METHODS: In an initial experimental study, we devised a model mannequin eye to investigate how air puff pressure and IOP of the eye affected aerosol generation. In the human study including 20 healthy volunteer control subjects, the number of tear aerosol particles generated at 20 and 40 mm Hg air puff pressures with and without eye drop was investigated. The recorded aerosol visualization video was analyzed and the number of aerosol particles generated in 5 seconds after IOP measurement was measured. RESULTS: The experimental and human studies confirmed the aerosol generation during NCT measurements. In the experimental study, when the air puff pressures were set at 20 and 40 mm Hg, a lower IOP (5 mm Hg) generated significantly more aerosols than a higher IOP (25 mm Hg) (20 mm Hg, P = .0159; 40 mm Hg, P = .0079). There was also a significant positive correlation between the air puff pressure and the number of aerosol particles in both high- and low-IOP eyes (P < .001). At an air puff pressure of 40 mm Hg, the amount of aerosol generated was significantly higher with eye drop than without eye drop (P = .047). CONCLUSIONS: NCT generates significant aerosolization from the tear film, the amount of which is determined by the IOP and the air puff pressure and the presence of eye drop use before the measurements.

Hydrodynamic Interaction Between Tear Film and Air Puff From Noncontact Tonometry.

PURPOSE: The purpose of this study was to investigate the mechanism of potential droplet formation in response to air puff deformation with two noncontact tonometers (NCTs). METHODS: Twenty healthy volunteers were examined using two NCTs, Ocular Response Analyzer and Corvis ST, and two contact tonometers, iCare and Tono-Pen. High-speed videos of the tear film response were captured with at spatial resolution of 20 microns/pixel at 2400 fps. Droplet size, droplet velocity, distance between air puff impact location, and the tear meniscus-lid margin were characterized. RESULTS: One subject was excluded due to technical issues. Droplets were detected only in tests with instilled eye drop. Videos showed the tear film rolls away from the apex while remaining adherent to the ocular surface due to the tendency of the fluid to remain attached to a solid surface explained by the Coanda effect. Twelve out of 38 videos with an eye drop administration showed droplet formation. Only one resulted in droplets with predominantly forward motion, which had the shortest distance between air puff impact location and lower meniscus. This distance on average was 5.9 ± 1.1 mm. The average droplet size was 500 ± 200 µm. CONCLUSIONS: Results indicate no droplet formation under typical clinical setting. Hence, standard clinical use of NCT tests is not expected to cause droplets. NCT testing with eye drop administration showed droplet formation at the inferior eyelid boundary, which acts as a barrier and interrupts tear flow. TRANSLATIONAL RELEVANCE: Study of tear film interaction with NCT air puff shows that these tonometers are not expected to cause droplet formation in standard use and that if external drops are required, both eyelids should be held if patients need assistance to maintain open eyes to avoid droplets with predominantly forward motion.

New Internet of Medical Things for Home-Based Treatment of Anorectal Disorders.

Home-based healthcare provides a viable and cost-effective method of delivery for resource- and labour-intensive therapies, such as rehabilitation therapies, including anorectal biofeedback. However, existing systems for home anorectal biofeedback are not able to monitor patient compliance or assess the quality of exercises performed, and as a result have yet to see wide spread clinical adoption. In this paper, we propose a new Internet of Medical Things (IoMT) system to provide home-based biofeedback therapy, facilitating remote monitoring by the physician. We discuss our user-centric design process and the proposed architecture, including a new sensing probe, mobile app, and cloud-based web application. A case study involving biofeedback training exercises was performed. Data from the IoMT was compared against the clinical standard, high-definition anorectal manometry. We demonstrated the feasibility of our proposed IoMT in providing anorectal pressure profiles equivalent to clinical manometry and its application for home-based anorectal biofeedback therapy.

Same day barium esophagography and high-resolution manometry during the COVID-19 pandemic.

PURPOSE: Double contrast barium esophagography (BAS) and high-resolution manometry (HRM) are traditionally performed on separate days to allow for pre-procedural fasting. In an effort to minimize COVID-19 exposure and improve appointment efficiency with required pre-procedure testing, we permitted same day HRM prior to BAS. Our study aimed to evaluate the adequacy of barium mucosal coating with same day HRM prior to BAS compared to BAS alone. METHODS: We performed a retrospective pilot cohort study including 14 patients undergoing same day HRM prior to BAS and 20 patients undergoing BAS alone over an 8-month interval during the COVID-19 pandemic. Three abdominal imaging subspecialty-trained radiologists blindly reviewed the images and graded adequacy of esophageal coating on a 4-point scale with a score of 1 representing inadequate coating and 4 representing optimal coating. RESULTS: For the cohort studied thus far, the mean grade of the HRM and BAS group was 3.17 with a standard deviation of 0.66. The mean grade of the BAS alone group was 3.13 with a standard deviation of 0.79. There was no statistical difference in the adequacy of esophageal coating between the two groups (p-value 0.97). CONCLUSION: Same day HRM prior to BAS has no detrimental effect on barium mucosal coating compared to BAS alone. Though created to limit patient exposures during the COVID pandemic, same day BAS and HRM may prevent delays in care and improve convenience towards improved patient-centered care beyond the pandemic.

In-vivo evidence of systemic endothelial vascular dysfunction in COVID-19.

BACKGROUND: Endothelial dysfunction is one of the underlying mechanisms to vascular and cardiac complications in patients with COVID-19. We sought to investigate the systemic vascular endothelial function and its temporal changes in COVID-19 patients from a non-invasive approach with reactive hyperemia peripheral arterial tonometry (PAT). METHODS: This is a prospective, observational, case-control and blinded study. The population was comprised by 3 groups: patients investigated during acute COVID-19 (group 1), patients investigated during past COVID-19 (group 2), and controls 1:1 matched to COVID-19 patients by demographics and cardiovascular risk factors (group 3). The natural logarithmic scaled reactive hyperemia index (LnRHI), a measure of endothelium-mediated dilation of peripheral arteries, was obtained in all the participants and compared between study groups. RESULTS: 144 participants were enrolled (72 COVID-19 patients and 72 matched controls). Median time from COVID-19 symptoms to PAT assessment was 9.5 and 101.5 days in groups 1 and 2, respectively. LnRHI was significantly lower in group 2 compared to both group 1 and controls (0.53 ± 0.23 group 2 vs. 0.72 ± 0.26 group 1, p = 0.0043; and 0.79 ± 0.23 in group 3, p < 0.0001). In addition, within group 1, it was observed a markedly decrease in LnRHI from acute COVID-19 to post infection stage (0.73 ± 0.23 vs. 0.42 ± 0.26, p = 0.0042). CONCLUSIONS: This study suggests a deleterious effect of SARS-CoV-2 infection on systemic vascular endothelial function. These findings open new venues to investigate the clinical implication and prognostic role of vascular endothelial dysfunction in COVID-19 patients and post-COVID syndrome using non-invasive techniques.

The impact of surgical masks on the nasal function in the COVID-19 era.

BACKGROUND: The Covid-19 pandemics has obliged to using different types of personal protective devices (PPD) for a prolonged time of the day, especially in the Health Centers, with preference of surgical masks (SM) during the first pandemic waves. AIMS/OBJECTIVES: This study was designed to assess the eventual changes of the nasal respiratory condition during continuous SM wearing. MATERIAL AND METHODS: Fourteen healthcare professionals filled a visual analogue scale (VAS) questionnaire for the detection of eventual nasal breathing impairment or symptoms. Nasal resistance and flow values were obtained via the active anterior rhinomanometry (AAR) that was performed under the basal condition, as well as immediately after wearing the surgical mask (SM) and 3 h after its continuous use. RESULTS: The increase of inspiratory resistance was significantly correlated to the reduction of the maximum flux, when comparing SM parameters to the basal ones (r = -0.70, p < .05). At VAS evaluation, SM wearing showed to induce itching in 70% of the subjects, nasal dryness in 55%, nasal blockage in 50%, headache in 39%, watery nasal discharge in 20% and sneezing in 18%. CONCLUSIONS AND SIGNIFICANCE: The SMs do not induce evident physiological variations of the nasal function due to a compensatory respiratory mechanism that, despite a progressive increase of nasal resistances, is not inducing significant changes of the nasal fluxes.

Impact of the COVID-19 pandemic on high-resolution manometry and peroral endoscopic myotomy for esophageal motility disorder in Japan.

AIM: To elucidate the impact of the coronavirus disease 2019 (COVID-19) on the practice of high-resolution manometry (HRM) and peroral endoscopic myotomy (POEM) in Japan. METHODS: We utilized a large-scale database involving 14 high-volume centers in Japan to investigate changes in the numbers of HRM and POEM procedures performed and outcomes of POEM between 2019 and 2020. A questionnaire survey was also conducted to analyze pandemic-associated changes in the HRM and POEM protocols. RESULTS: Compared to that in 2019, the number of HRM and POEM procedures decreased by 17.2% (1587-1314) and 20.9% (630-498), respectively. These declines were prominent during the state of emergency from April to May 2020, particularly in pandemic areas. HRM and POEM in nonpandemic areas were relatively unaffected. From 2019 to 2020, there was a 0.4% (254-248) decrease in POEM cases within the prefecture, but the number outside the prefecture decreased by 33.6% (372-247). During the pandemic, the safety and efficacy of POEM were maintained. The implementation of personal protective equipment (PPE) measures varied among facilities, and PPE for POEM was relatively insufficient compared to that for HRM. CONCLUSION: The COVID-19 pandemic influenced HRM and POEM practices in Japan. It is necessary to establish a sufficient system for HRM and POEM in each hospital as well as countrywide to overcome the effects of the pandemic.

Quantitative Evaluation of Aerosol Generation from Non-contact Tonometry and its Correlation with Tear Film Characteristics.

INTRODUCTION: Ophthalmologists are inevitably exposed to tears and ocular discharge during ophthalmologic examinations and are at high risk for SARS-CoV-2 infection. To understand the role of aerosols in disease transmission, we adopted a prospective cross-sectional study design and investigated the count and size distribution of aerosols generated by a non-contact tonometer and its correlation with individual tear film characteristics. METHODS: This study constituted two parts. The study population included outpatients who underwent an intraocular pressure examination in an intraocular pressure examination room (Part I) and 20 participants who underwent an intraocular pressure examination in a laboratory (Part II). The following main outcomes were measured: aerosol counts at 0, 50, 100, 150, and 200 cm from the non-contact tonometer (Part I); aerosol counts after each participant underwent non-contact tonometry, and lipid layer thickness score and tear film break-up time (Part II). RESULTS: The aerosol count decreased with increasing distance from the tonometer. The aerosol count at 0 cm had the highest value compared to that at other distances. For aerosols of diameters 0.25-0.5 µm and 0.5-1.0 µm, the count decreased at 50 cm and remained stable at further distances. For aerosols of diameters 1.0-2.5 µm and ≥ 2.5 µm, the count dropped progressively at all five distances. The aerosol count from each tonometer correlated positively with the lipid layer thickness score (r = 0.490, P = 0.028), whereas the aerosol count correlated negatively with the tear film break-up time (r = - 0.675, P = 0.001). CONCLUSIONS: Aerosols tended to coagulate during diffusion. A 50-cm distance from the tonometer could confer safety from aerosols with < 1.0-µm diameter. Aerosols generated during non-contact tonometry could contain a lipid layer component. Moreover, tear film stability could affect aerosol generation. Protective eyewear is recommended for reducing infection risk from aerosols. Individual tear film characteristics should be considered during non-contact tonometry.

[Functional Exams in the gastroenterology - new developments and tips for the common practice]. / Gastroenterologische Funktionsdiagnostik ­ neue Entwicklungen und Tipps für die Praxis.

The functional gastrointestinal disorders (FGIDs) have a high prevalence and are associated with high healthcare costs. The diagnosis of these diseases could be difficult and require func-tional tests such as high-resolution manometry (HRM) of the esophagus, anorectal manometry and H2-Breathtests. Due to the COVID-19 Pandemic and the fear of infections there was a marked reduction in the number of performed exams in the last months - nevertheless some exams are necessary, in order to exclude or to diagnose important and dangerous diseases like Achalasia. Goal of this article is to present some new and relevant developments in the field. The HRM of the esophagus is the diagnostic standard for Achalasia, a rare clinical condi-tion associated to dysphagia - new European guidelines suggests a safe strategy in perform-ing the pneumatic dilatation.The intestinal methanogen overgrowth (IMO) is a clinical condition caused by a high production of methane in the small intestine due to overgrowth of Methanobrevibacter smithii, this condition could be in some patients associated with irritable bowel syndrome.

Risk of COVID-19 transmission in esophageal, anorectal manometry and 24-hour impedance-pH monitoring.

BACKGROUND: the impact of the COVID-19 pandemic has led to the interruption of most manometry or impedance-pH monitoring studies. The risk of restarting activities is unknown. OBJECTIVE: assess the risk of SARS-CoV-2 virus infection, both to patients and healthcare workers, in relation to esophageal and anorectal functional tests during the pandemic without protective measures. METHOD: a questionnaire was designed to determine whether patients and healthcare workers had COVID-19, confirmed by either a test or compatible symptoms, after functional studies were performed from January until March 2020. RESULTS: the survey was answered by 263 (92.9 %) patients. Four (1.52 %) patients had confirmed COVID-19 in the two weeks after the functional test (adjusted rate 8.34 cases per 1,000 [95 % CI -0.06-16.74], OR 0.84 [95 % CI: 0.83-0.85], p < 0.001) and no patient after anorectal manometry. Another five had only compatible symptoms, for a total of nine patients (3.42 %) (adjusted rate 27.50 cases/1,000 [95 % CI: 7.27-47.74], OR 2.84 [95 % CI: 2.81-2.87]). In the total study period, 18.25 % had confirmed COVID-19 or compatible symptoms. The average number of days between the procedure and the first day of symptoms was progressively shortened (January: 56 days, February: 33 days, March: 10.5 days). Two of ten healthcare workers (20 %) had confirmed COVID-19. CONCLUSIONS: the risk of COVID-19 infection when performing functional tests is low and more related to the evolution of the pandemic rather than to the procedure itself. The small number of healthcare workers included in the study does not allow a definitive conclusion to be drawn on their risk of infection.

Recommendations for the reopening and activity resumption of the neurogastroenterology units in the face of the COVID-19 pandemic. Position of the Sociedad Latinoamericana de Neurogastroenterología. / Recomendaciones para la reapertura y reinicio de actividades de las Unidades de Neurogastroenterología ante la pandemia por COVID-19. Posicionamiento de la Sociedad Latinoamericana de Neurogastroenterología.

The COVID-19 pandemic has forced the establishment of preventive measures against contagion during the performance of diagnostic and therapeutic tests in gastroenterology. Digestive tract motility tests involve an intermediate and elevated risk for the transmission of COVID-19 infection. Given their elective or non-urgent indication in the majority of cases, we recommend postponing those tests until significant control of the infection rate in each Latin American country has been achieved during the pandemic. When the health authorities allow the return to normality, and in the absence of an effective treatment for or preventive vaccine against COVID-19 infection, we recommend a strict protocol for classifying patients according to their infectious-contagious status through the appropriate use of tests for the detection of the virus and the immune response to it, and the following of protective measures by the healthcare personnel to prevent contagion during the performance of a gastrointestinal motility test.