CS-VIBE accelerates cranial nerve MR imaging for the diagnosis of facial neuritis: comparison of the diagnostic performance of post-contrast MPRAGE and CS-VIBE.

OBJECTIVE: We aimed to compare the diagnostic performance of post-contrast 3D compressed sensing volume-interpolated breath-hold examination (CS-VIBE) and 3D T1 magnetization-prepared rapid-acquisition gradient-echo (MPRAGE) in detecting facial neuritis. MATERIALS AND METHODS: Between February 2019 and September 2019, 60 patients (30 facial palsy patients and 30 controls) who underwent contrast-enhanced cranial nerve MRI with both conventional MPRAGE and CS-VIBE (scan time: 6 min 8 s vs. 2 min 48 s) were included in this retrospective study. All images were independently reviewed by three radiologists for the presence of facial neuritis. In patients with facial palsy, signal-to-noise ratio (SNR) of the pons, enhancement degree and contrast-to-noise ratio (CNRnerve-CSF) of the facial nerve were measured. The overall image quality, artifacts, and facial nerve discrimination were analyzed. The sensitivity and specificity of both sequences were calculated with the clinical diagnosis as a reference. RESULTS: CS-VIBE had comparable performance in the detection of facial neuritis to that of MPRAGE (sensitivity and specificity, 97.8% and 99.4% vs. 100.0% and 99.4% in pooled analysis; 97.8% and 98.9% vs. 100.0% and 98.9% in patents with facial palsy, p value > 0.05 for all). CS-VIBE showed significantly lower SNR (p value < 0.001 for all), but significantly higher CNRnerve-CSF (p value < 0.05 for all) than MPRAGE. CS-VIBE also performed better in the overall image quality, artifacts, and facial nerve discrimination than MPRAGE (p value < 0.001 for all). CONCLUSION: CS-VIBE achieved comparable diagnostic performance for facial neuritis compared to the conventional MPRAGE, with the scan time being half of that of MPRAGE. KEY POINTS: • Post-contrast 3D CS-VIBE MRI is a reliable method for the diagnosis of facial neuritis. • CS-VIBE reduces the scan time of cranial nerve MRI by more than half compared to conventional T1-weighted image. • CS-VIBE had better performance in contrast-to-noise ratio and favorable image quality compared with conventional T1-weighted image.

The effects of climate on the incidence of benign paroxysmal positional vertigo.

Benign paroxysmal positional vertigo (BPPV) is one of the most common vestibular disorders. An investigation into the factors related to BPPV could contribute to its prevention and appropriate management. We investigated the association between climatic factors and incidence of BPPV in this study. A total of 365 patients who were diagnosed with idiopathic BPPV in the emergency room of our hospital in 2015 were included. The number of patients diagnosed with BPPV per week was calculated (every week). Climatic factors, including daily average humidity, temperature, atmospheric pressure, cloud amount, sunshine amount, and daylight time, were documented daily. The weekly mean climatic value in each week was calculated. Simple correlation analysis and multivariate regression analyses were performed to identify climatic factors associated with the number of patients diagnosed with BPPV. Simple correlation analysis revealed a significant association between the humidity (r = 0.276, p = 0.048), temperature (r = 0.275, p = 0.049), and cloud amount (r = 0.293, p = 0.035) and the number of BPPV patients diagnosed per week. Multivariate regression analysis revealed that only the cloud amount was a statistically significant factor associated with the number of BPPV patients diagnosed every week. A significant positive association was discovered between the cloud amount and BPPV incidence. Cloud amount can therefore have an association with the incidence of BPPV.

Antioxidant effect of human placenta hydrolysate against oxidative stress on muscle atrophy.

Sarcopenia, which refers to the muscle loss that accompanies aging, is a complex neuromuscular disorder with a clinically high prevalence and mortality. Despite many efforts to protect against muscle weakness and muscle atrophy, the incidence of sarcopenia and its related permanent disabilities continue to increase. In this study, we found that treatment with human placental hydrolysate (hPH) significantly increased the viability (approximately 15%) of H2 O2 -stimulated C2C12 cells. Additionally, while H2 O2 -stimulated cells showed irregular morphology, hPH treatment restored their morphology to that of cells cultured under normal conditions. We further showed that hPH treatment effectively inhibited H2 O2 -induced cell death. Reactive oxygen species (ROS) generation and Mstn expression induced by oxidative stress are closely associated with muscular dysfunction followed by atrophy. Exposure of C2C12 cells to H2 O2 induced abundant production of intracellular ROS, mitochondrial superoxide, and mitochondrial dysfunction as well as myostatin expression via nuclear factor-κB (NF-κB) signaling; these effects were attenuated by hPH. Additionally, hPH decreased mitochondria fission-related gene expression (Drp1 and BNIP3) and increased mitochondria biogenesis via the Sirt1/AMPK/PGC-1α pathway and autophagy regulation. In vivo studies revealed that hPH-mediated prevention of atrophy was achieved predominantly through regulation of myostatin and PGC-1α expression and autophagy. Taken together, our findings indicate that hPH is potentially protective against muscle atrophy and oxidative cell death.

Therapeutic potential of topically administered γ-AlOOH on 2,4-dinitrochlorobenzene-induced atopic dermatitis-like lesions in Balb/c mice.

Boehmite (γ-AlOOH) has a wide range of applications in a variety of industrial and biological fields. However, little is known about its potential roles in skin diseases. The current study investigated its effect on atopic dermatitis (AD). Following characterization, cytotoxicity, pro-inflammatory response and oxidative stress associated with boehmite were assessed, using TNF-α-induced keratinocytes and mast cells. In addition, therapeutic effects of boehmite, topically administered to Balb/c mice induced by 2,4-dinitrochlorobenzene (DNCB), were evaluated. Expression of cytokines (TLSP, IL-25 and IL-33) and the generation of ROS from keratinocytes induced by TNF-α were significantly inhibited by boehmite without affecting cell viability. MAPKs (ERK, JNK and p38) required for cytokine expression were suppressed by boehmite treatment. Up-regulation of cytokines (TSLP, IL-4, IL-5, IL-13, RANTES) in human mast cells treated with phorbol 12-myristate 13-acetate and calcium ionophore was also suppressed by boehmite. Boehmite improved the AD severity score, epidermal hyperplasia and transepidermal water loss in DNCB-induced AD-like lesions. Moreover, Th2-mediated cytokine expression, mast cell hyperplasia and destruction of the skin barrier were improved by boehmite treatment. Overall, we demonstrated that boehmite may potentially protect against AD.

First recognized n-butanol concentration may be simple and useful index for assessing olfactory dysfunction in geriatric patients.

The KVSSII is widely used to evaluate olfactory function in the Korean population. We evaluated the usefulness of the first recognized n-butanol concentration, which is obtained at the beginning part of KVSS II, in predicting olfactory dysfunction. Three hundred seventy two subjects were enrolled in our study. The results of KVSS II and the demographic characteristics were statistically analyzed. The first recognized n-butanol concentration was positively correlated with the result of KVSS II. The mean value of first recognized n-butanol concentration was 5.59 ± 1.42 in normosmia, 4.10 ± 1.40 in hyposmia, and 0.84 ± 1.68 in the anosmia group. By ROC curve, cut-off value of 2.5 showed sensitivity of 85.9% and specificity of 90.6% for anosmia, and cut-off value of 4.5 showed sensitivity of 77.6% and specificity of 69.8% for hyposmia. Consequently, we suggest that it may be useful in assessing olfactory function, in geriatric patients who are not able to tolerate conventional KVSS II.

Inhibitory effect of 660-nm LED on melanin synthesis in in vitro and in vivo.

BACKGROUND: Skin hyperpigmentary disorders including postinflammatory hyperpigmentation, melasma, solar lentigines, and conditions like freckles are common. The light-emitting diodes (LEDs) are the latest category of nonthermal and noninvasive phototherapy to be considered in skin pigmentation disorder treatment. PURPOSE: The purpose of this study was to investigate the effects of 660-nm LED on inhibition of melanogenesis. We investigated whether a 660-nm LED affected melanin synthesis in in vitro and in vivo models, and we explored the mechanisms involved. METHODS: The inhibitory effect of 660-nm LED on melanin synthesis was evaluated in B16F10 cells and HRM-2 melanin-possessing hairless mice were used to evaluate the antimelanogenic effects of 660-nm LED. RESULTS: Interestingly, 660-nm LED inhibited alpha-melanocyte-stimulating hormone-induced tyrosinase activity in B16F10 cells. We also found that 660-nm LED decreased MITF and tyrosinase expression and induced the activation of ERK. These findings suggest that the depigmenting effects of 660-nm LED result from downregulation of MITF and tyrosinase expression due to increased ERK activity. The 660-nm LED reduced UVB-induced melanogenesis in the skin of HRM-2 via downregulation of tyrosinase and MITF. CONCLUSION: These findings suggest 660-nm LED is a potentially depigmentation strategy.

The Anti-Inflammatory Effects of Oral-Formulated Tacrolimus in Mice with Experimental Autoimmune Encephalomyelitis.

Multiple sclerosis (MS) is a T-lymphocyte-mediated autoimmune disease that is characterized by inflammation in the central nervous system (CNS). Although many disease-modifying therapies (DMTs) are presumed effective in patients with MS, studies on the efficacy and safety of DMTs for preventing MS relapse are limited. Therefore, we tested the immunosuppressive anti-inflammatory effects of oral-formulated tacrolimus (FK506) on MS in a mouse model of experimental autoimmune encephalomyelitis (EAE). The mice were randomly divided into 3 experimental groups: an untreated EAE group, a low-dose tacrolimus-treated EAE group, and a high-dose tacrolimus-treated EAE group. After autoimmunization of the EAE mice with myelin oligodendrocyte glycoprotein, symptom severity scores, immunohistochemistry of the myelination of the spinal cord, and western blotting were used to evaluate the EAE mice. After the autoimmunization, the symptom scores of each EAE group significantly differed at times. The group treated with the larger tacrolimus dose had the lowest symptom scores. The tacrolimus-treated EAE groups exhibited less demyelination and inflammation and weak immunoreactivity for all of the immunization biomarkers. Our results revealed that oral-formulated tacrolimus inhibited the autoimmunization in MS pathogenesis by inactivating inflammatory cells.

Impact of control of blood glucose level during treatment of sudden deafness in diabetics: relationship with prognosis.

The objective of this study is to investigate the impact of control of blood glucose level during treatment of sudden deafness. A retrospective study was performed involving 197 patients from January, 2011 to September, 2015. All patients were administrated prednisolone (Pharmaprednisolone tab®, 5 mg/T; KoreaPharma) p.o under the following regimen: 60 mg/day for 4 days, 40 mg/day for 2 days, 30 mg/day for 1 day, 20 mg/day for 1 day, and 10 mg/day for 2 days. During treatment, pure tone audiometry and blood glucose level were investigated for each patient and the results were statistically analyzed. Mean hearing improvement was 19.2 dB for the non-diabetes group and 24.8 dB for the diabetes group. The greater improvement for diabetics was not statistically significant (p = 0.146). Hearing improvement was 25.1 dB for subjects with mean blood glucose <200 mg/dl and 24.6 dB for subjects with mean blood glucose >200 mg/dl; the difference was not statistically significant (p = 0.267). Mean blood glucose level was 200.8 mg/dl for subjects with hearing improvement >20 dB and 181.8 mg/dl for subjects with hearing improvement <20 dB; the difference was not statistically significant (p = 0.286). Control of blood glucose level during treatment of sudden deafness does not have a direct effect on prognosis.

The Possible Role of Endoscopy in Diagnosis of Benign Tumors of the Nasal Cavity.

BACKGROUND: Benign tumors of the nasal cavity represent a large variety of different histopathological entities. Although advances in nasal endoscopy over the past couple of decades have made it possible to detect the vast majority of these lesions, accurate diagnosis and proper management can be delayed since they are misdiagnosed as inflammatory paranasal sinus disease or simple epistaxis. OBJECTIVES: The aims of the present study are to determine the relative incidence of benign tumor of the nasal cavity and to provide typical endoscopic features of common tumors. This information can potentially improve clinicians' comprehension of benign tumors of the nasal cavity and be helpful in making provisional diagnosis. RESULTS: The present study included 32 patients (25 males, 7 females) with benign tumor of the nasal cavity, which was pathologically confirmed. The most common symptom was nasal obstruction (12/37.5%), followed by recurrent epistaxis (7/21.9%). The most common involving site was anterior nasal septum (17/53.1%), followed by nasal vestibule (7/18.8%) and inferior turbinate (4/12.5%). The most common pathology was squamous papilloma (12/37.5%), followed by lobular capillary hemangioma (7/21.9%). The provisional diagnosis was easily made by nasal endoscopy in 19 (59.4%) patients with typical endoscopic features, especially squamous papilloma, lobular capillary hemangioma, and verruca vulgaris. CONCLUSIONS: Clinicians should keep in mind that benign tumors of the nasal cavity are included in the differential diagnosis of unilateral nonspecific nasal symptoms such as nasal obstruction and epistaxis. Also, clinicians should be familiar with the endoscopic findings of various benign tumors and perform the diagnostic approaches with the provisional diagnosis on the basis of those findings.

Streptococcus sanguinis isolated from filler granuloma: Successful treatment with incision and drainage.

Filler granuloma is considered to be the result of delayed immune responses; growing evidence suggests that they may be secondary to biofilm formation. Dermal filler is technically a foreign body, and as the development of newer generations of dermal fillers lengthens their duration, it is possible that there is also an increased risk of biofilm formation. Here, we present a case report of a patient with Streptococcus sanguinis isolated from a filler granuloma, suggestive of biofilm formation. This case demonstrates the effective use of antibiotics after incision and drainage on antibiotic resistant biofilm.

Effect of a 308-nm excimer laser on atopic dermatitis-like skin lesions in NC/Nga mice.

BACKGROUND AND OBJECTIVE: Atopic dermatitis (AD) is a common inflammatory skin disease that can affect all age groups. It has a relapsing course, which dramatically affects the quality of life of patients. A 308-nm excimer laser has been reported to be a safe and effective treatment for inflammatory skin diseases, although the range of potential application has not been fully explored. The purpose of this study was to evaluate the therapeutic effects of a 308-nm laser on AD-like skin lesions in NC/Nga mice. STUDY DESIGN/MATERIALS AND METHODS: Dermatophagoides farinae-exposed NC/Nga mice with a clinical score of 12 were treated with either a 308-nm excimer laser or narrowband-UVB (NB-UVB). The effects of the 308-nm excimer laser were evaluated by dermatitis scores, skin histology, skin barrier function, and immunological parameters, including IgE and Th2-mediated cytokines. RESULTS: The 308-nm excimer laser significantly reduced the severity of skin lesions and decreased the total serum levels of IgE and Th2-mediated cytokines. The excimer laser also significantly reduced the inflammatory cellular infiltrate into AD-induced skin lesions. Moreover, treatment with the 308-nm excimer laser led to recovery of skin barrier function in AD-induced skin lesions. CONCLUSION: The 308-nm excimer laser can be considered a valid and safe therapeutic option for the treatment of localized AD. Lasers Surg. Med. 48:629-637, 2016. © 2016 Wiley Periodicals, Inc.

Investigating skin penetration depth and shape following needle-free injection at different pressures: A cadaveric study.

BACKGROUND AND OBJECTIVES: The effectiveness of needle-free injection devices in neocollagenesis for treating extended skin planes is an area of active research. It is anticipated that needle-free injection systems will not only be used to inject vaccines or insulin, but will also greatly aid skin rejuvenation when used to inject aesthetic materials such as hyaluronic acid, botulinum toxin, and placental extracts. There has not been any specific research to date examining how materials penetrate the skin when a needle-free injection device is used. In this study, we investigated how material infiltrates the skin when it is injected into a cadaver using a needle-free device. STUDY DESIGN/MATERIALS AND METHODS: Using a needle-free injector (INNOJECTOR™; Amore Pacific, Seoul, Korea), 0.2 ml of 5% methylene blue (MB) or latex was injected into cheeks of human cadavers. The device has a nozzle diameter of 100 µm and produces a jet with velocity of 180 m/s. This jet penetrates the skin and delivers medicine intradermally via liquid propelled by compressed gasses. Materials were injected at pressures of 6 or 8.5 bars, and the injection areas were excised after the procedure. The excised areas were observed visually and with a phototrichogram to investigate the size, infiltration depth, and shape of the hole created on the skin. A small part of the area that was excised was magnified and stained with H&E (×40) for histological examination. RESULTS: We characterized the shape, size, and depth of skin infiltration following injection of 5% MB or latex into cadaver cheeks using a needle-free injection device at various pressure settings. Under visual inspection, the injection at 6 bars created semi-circle-shaped hole that penetrated half the depth of the excised tissue, while injection at 8.5 bars created a cylinder-shaped hole that spanned the entire depth of the excised tissue. More specific measurements were collected using phototrichogram imaging. The shape of the injection entry point was consistently spherical regardless of the amount of pressure used. When injecting 5% MB at 6 bars, the depth of infiltration reached 2.323 mm, while that at 8.5 bars reached 8.906 mm. The area of the hole created by the 5% MB injection was 0.797 mm(2) at 6 bars and 0.242 mm(2) at 8.5 bars. Latex injections reached a depth of 3.480 mm at 6 bars and 7.558 mm at 8.5 bars, and the areas were measured at 1.043 mm(2) (6 bars) and 0.355 mm(2) (8.5 bars). Histological examination showed that the injection penetrated as deep as the superficial musculoaponeurotic system at 6 bars and the masseter muscle at 8.5 bars. CONCLUSION: When injecting material into the skin using a pneumatic needle-free injector, higher-pressure injections result in a hole with smaller area than lower-pressure injections. The depth and shape of skin penetration vary according to the amount of pressure applied. For materials of low density and viscosity, there is a greater difference in penetration depth according to the degree of pressure. Lasers Surg. Med. 48:624-628, 2016. © 2016 Wiley Periodicals, Inc.

Gain-switched 311-nm Ti:Sapphire laser might be a potential treatment modality for atopic dermatitis.

Phototherapy with 311-nm narrowband-UVB (NBUVB) is an effective adjuvant treatment modality for atopic dermatitis (AD). In this study, we evaluated the therapeutic effect of the newly developed gain-switched 311-nm Ti:Sapphire laser device using a NC/Nga mouse AD model. A total number of 50 mice were used in this study. Atopic dermatitis (AD) was induced in mice by exposure to Dermatophagoides farina. These, NC/Nga mice were then treated with conventional 311-nm NBUVB or the newly developed gain-switched 311-nm Ti:Sapphire laser. The clinical features, dermatitis severity scores, and scratching behavior were assessed. In addition, serologic analyses including inflammatory cytokines and histological analyses were performed. Gain-switched 311-nm Ti:Sapphire laser improved the AD-like skin lesions, severity, and symptoms of AD in the NC/Nga mouse model. This new laser also modulated the immune response found in the AD model, including hyper-IgE, upregulated Th2 cytokines, and the Th2-mediated allergic inflammatory reaction. Gain-switched 311-nm Ti:Sapphire laser shows therapeutic promise via an immune-modulation mechanism in an AD mouse model. These data suggest that gain-switched 311-nm Ti:Sapphire laser may be useful as a targeted phototherapy modality for AD.

Combined treatment with 578-/511-nm copper bromide laser and light-emitting diodes for post-laser pigmentation: a report of two cases.

Postinflammatory hyperpigmentation (PIH) developing after cosmetic procedures such as lasers and chemical peels is always a concern, especially in darker skin types. We report two cases of laser-related PIH of the face successfully treated by combined therapy with 578-/511-nm copper bromide laser and light-emitting diodes (LED). Good cosmetic results were achieved in both patients. The side effects during and after treatment included a mild stinging and redness, but these were resolved within several days without any treatment. Combined 578-/511-nm copper bromide laser with LED provided safe and effective treatment for post-laser pigmentation in Korean patients.

Social distancing during the COVID-19 pandemic: Potential impact and correlation with asthma.

BACKGROUND: Non-pharmaceutical interventions have been implemented globally to control the COVID-19 pandemic and have been shown to alleviate both allergies and respiratory infections. Although mask-wearing is an accepted non-pharmaceutical intervention, the effects of social distancing have not been thoroughly evaluated. OBJECTIVES: To evaluate the effects of social distancing on asthma trends in Seoul, South Korea. METHODS: This study included data from the National Health Insurance Service of South Korea, covering approximately 10 million people in Seoul. Daily and monthly data of patients with asthma from 2018 to 2021 were examined, and the degree of social distancing performance was measured using the number of subway users as an index. Pearson's correlation coefficient was used to determine the relationship between the two indices. The change-point detection technique, cross-correlation, and Granger causality method were used to assess the temporal causality between social distancing and asthma. RESULTS: The number of patients with asthma decreased by 42.4 % from 2019 to 2020, while that of subway users decreased by 26.3 % during this period. Pearson's correlation analysis revealed significant positive correlations. Asthma and subway users showed a significant change in incidence following the implementation of social distancing; subway users showed a causal relationship with patients with asthma. CONCLUSION: Our results showed that the number of subway users decreased after the implementation of strict social distancing, coinciding with a decrease in the number of patients with asthma. These findings suggest that social distancing measures implemented to control COVID-19 may reduce the incidence and exacerbation of asthma.

Impact of COVID-19 Pandemic on the Incidence of Pediatric Acute Otitis Media in Seoul, South Korea.

OBJECTIVE: The implementation of nonpharmaceutical interventions (NPIs) for coronavirus disease 2019 (COVID-19) may affect the incidence of infectious diseases. This study aimed to evaluate the changes in the incidence of pediatric acute otitis media (AOM) after the COVID-19 outbreak in Seoul, South Korea. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary referral center. PATIENTS: We ascertained the daily number of COVID-19 and pediatric AOM patients between January 20, 2020, and June 19, 2020. During the same period, the number of children using public transportation was used as an index for implementing NPIs. The same period 1 year ago was set as the control period. INTERVENTION: Diagnostic. MAIN OUTCOME MEASURE: The differences in the incidence of AOM and implementation of NPIs between the COVID-19 pandemic and control period were analyzed using segmented regression analyses. Negative values of difference meant that the number in the COVID-19 pandemic period declined compared with the control period. RESULTS: The study period was divided into two sections based on the change point of the COVID-19 cases. In the first period, the increased number of COVID-19 cases decreased, and in the second period, the number of COVID-19 cases increased again. Similar trends were observed in the incidence of AOM and NPI implementation. Before the change point, the study found a significant decreasing trend in the differences in pediatric AOM cases and children using public transportation. However, these trends changed after the change point, with a significant increase in both indices. CONCLUSION: Our findings indicate that NPIs for COVID-19 may influence the incidence of pediatric AOM.

Treatment Efficacy of Various Maneuvers for Lateral Canal Benign Paroxysmal Positional Vertigo With Apogeotropic Nystagmus: A Randomized Controlled Trial.

OBJECTIVES: The aim of this study was to determine the most effective treatment approach by comparing the impacts of various otolith reduction techniques in patients with apogeotropic lateral semicircular canal benign paroxysmal positional vertigo (LC-BPPV). METHODS: We performed a multicenter randomized prospective study from January to December 2015, involving 72 consecutive patients with apogeotropic LC-BPPV. The patients were divided into three treatment groups: therapeutic head-shaking (group A), the Gufoni-Appiani maneuver (group B), and the cupulolith repositioning maneuver (CuRM; group C). Each group underwent evaluation and treatment up to the fourth week. Treatment success was defined as the disappearance of positional vertigo and nystagmus. RESULTS: This study included 72 patients (49 male and 23 female), with a mean (±standard deviation) age of 55.4±13.5 years. The mean duration of vertigo experienced prior to treatment was 3.9±4.4 days. The mean latency and duration of nystagmus were 2.7±3.0 seconds and 47.9±15.8 seconds, respectively. The overall treatment frequency was 2.0±0.9. The number of treatments differed significantly among the three groups (P<0.05). After 4 weeks, the success rates for groups A, B, and C were 90.5%, 92.3%, and 100%, respectively. No significant difference was observed in the success rate across treatment. METHODS: and periods (P>0.05). However, CuRM was the only method with a 100% treatment success rate. CONCLUSION: While no clear difference was observed among the three treatments for LC-BPPV, CuRM was found to be superior to the other approaches in the long term.

Development of prediction models for the incidence of pediatric acute otitis media using Poisson regression analysis and XGBoost.

Otitis media has profound health and economic impact, and its occurrence is known to be influenced by air pollution and climate. The purpose of this study was to develop prediction models using climate and air pollution indicators for the occurrence of acute otitis media (AOM). The study was conducted from January 1, 2014, to December 31, 2019, and included pediatric patients (age < 12 years) diagnosed on their emergency room visit in our tertiary medical institution. We obtained data on the weekly number of AOM patients and the weekly average values of air pollution and climate indicators. Poisson regression analysis and eXtreme Gradient Boosting (XGBoost) were used to develop prediction models for the overall pediatric patients and for the patients classified according to sex (male and female) and age (< 2 years and ≥ 2 years). For the overall population, the correlation coefficients between the original and estimated data in the testing set were 0.441 (p < 0.001) and 0.844 (p < 0.001) for the models developed using Poisson regression analysis and XGBoost, respectively. The root-mean-square errors in the testing set were 3.094 and 1.856, respectively. For patients classified according to sex and age, the prediction models developed using XGBoost showed better performance than the models developed using Poisson regression analysis. In conclusion, this study successfully developed prediction models with air pollution and climate indicators for the incidence of pediatric AOM, using XGBoost. This model can be further developed to prevent pediatric AOM.

Machine Learning Models for Predicting the Occurrence of Respiratory Diseases Using Climatic and Air-Pollution Factors.

OBJECTIVES: Because climatic and air-pollution factors are known to influence the occurrence of respiratory diseases, we used these factors to develop machine learning models for predicting the occurrence of respiratory diseases. METHODS: We obtained the daily number of respiratory disease patients in Seoul. We used climatic and air-pollution factors to predict the daily number of patients treated for respiratory diseases per 10,000 inhabitants. We applied the relief-based feature selection algorithm to evaluate the importance of feature selection. We used the gradient boosting and Gaussian process regression (GPR) methods, respectively, to develop two different prediction models. We also employed the holdout cross-validation method, in which 75% of the data was used to train the model, and the remaining 25% was used to test the trained model. We determined the estimated number of respiratory disease patients by applying the developed prediction models to the test set. To evaluate the performance of each model, we calculated the coefficient of determination (R2) and the root mean square error (RMSE) between the original and estimated numbers of respiratory disease patients. We used the Shapley Additive exPlanations (SHAP) approach to interpret the estimated output of each machine learning model. RESULTS: Features with negative weights in the relief-based algorithm were excluded. When applying gradient boosting to unseen test data, R2 and RMSE were 0.68 and 13.8, respectively. For GPR, the R2 and RMSE were 0.67 and 13.9, respectively. SHAP analysis showed that reductions in average temperature, daylight duration, average humidity, sulfur dioxide (SO2), total solar insolation amount, and temperature difference increased the number of respiratory disease patients, whereas increases in atmospheric pressure, carbon monoxide (CO), and particulate matter ≤2.5 µm in aerodynamic diameter (PM2.5) increased the number of respiratory disease patients. CONCLUSION: We successfully developed models for predicting the occurrence of respiratory diseases using climatic and air-pollution factors. These models could evolve into public warning systems.