Prevalence, natural progression, and clinical practices of upper gastrointestinal subepithelial lesions in Korea: a multicenter study

Background/Aims@#This study aimed to evaluate the prevalence and natural progression of subepithelial lesions (SELs) in the upper gastrointestinal (UGI) tract. @*Methods@#The medical records of patients with UGI SELs who underwent endoscopic screening at eight university hospitals between January and December 2010 were retrospectively investigated. The follow-up evaluations were performed until December 2016. @*Results@#UGI SELs were found in 1,044 of the 65,233 participants screened (endoscopic prevalence, 1.60%; the total number of lesions, 1,062; mean age, 55.1±11.2 years; men, 53.6%). The median follow-up period was 48 (range, 8–74) months. SELs were most frequently found in the stomach (63.8%) and had a mean size of 9.9±6.1 mm. Endoscopic ultrasonography (EUS) was performed in 293 patients (28.1%). The most common lesions were leiomyomas, followed by gastrointestinal stromal tumors (GISTs), and ectopic pancreas. The proportions of SELs with malignant potential according to size were 3% (<1 cm), 22% (1–2 cm), 27% (2–3 cm), and 38% (≥3 cm). In gastric SELs larger than 1 cm, resections were performed in 20 patients because of an increase in size, of which 12 were found to be GISTs. @*Conclusions@#The prevalence of UGI SELs was 1.60%. Further, 23% of gastric SELs ≥1 cm were precancerous lesions, most followed by EUS and clinical decisions without initial pathological confirmation.

Accuracy of administrative claim data for gastric adenoma after endoscopic resection

Background/Aims@#Administrative databases provide valuable information for large-cohort studies. This study aimed to evaluate the diagnostic accuracy of an administrative database for resected gastric adenomas. @*Methods@#Data of patients who underwent endoscopic resection for benign gastric lesions were collected from three hospitals. Gastric adenoma cases were identified in the hospital database using International Classification of Diseases (ICD) 10-codes. The non-adenoma group included patients without gastric adenoma codes. The diagnostic accuracy for gastric adenoma was analyzed based on the pathological reports of the resected specimen. @*Results@#Among 5,095 endoscopic resections with codes for benign gastric lesions, 3,909 patients were included in the analysis. Among them, 2,831 and 1,078 patients were allocated to the adenoma and non-adenoma groups, respectively. Regarding the overall diagnosis of gastric adenoma with ICD-10 codes, the sensitivity, specificity, positive predictive value, and negative predictive value were 98.7%, 88.5%, 95.2%, and 96.8%, respectively. There were no significant differences in these parameters between the tertiary and secondary centers. @*Conclusions@#Administrative codes of gastric adenoma, according to ICD-10 codes, showed good accuracy and can serve as a useful tool to study prognosis of these patients in real-world data studies in the future.

Guidelines for the Use of Botulinum Toxin in Otolaryngology From the Korean Society of Laryngology, Phoniatrics and Logopedics Guideline Task Force

The Korean Society of Laryngology, Phoniatrics and Logopedics created a task force to establish clinical practice guidelines for the use of botulinum toxin (BT) in otolaryngology. We selected 10 disease categories: spasmodic dysphonia, essential vocal tremor, vocal fold granuloma, bilateral vocal fold paralysis, Frey’s syndrome, sialocele, sialorrhea, cricopharyngeal dysfunction, chronic sialadenitis, and first bite syndrome. To retrieve all relevant papers, we searched the CORE databases with predefined search strategies, including Medline (PubMed), Embase, the Cochrane Library, and KoreaMed. The committee reported 13 final recommendations with detailed evidence profiles. The guidelines are primarily aimed at all clinicians applying BT to the head and neck area. In addition, the guidelines aim to promote an improved understanding of the safe and effective use of BT by policymakers and counselors, as well as in patients scheduled to receive BT injections.

Clinical Practice Guideline: Clinical Efficacy of Nasal Surgery in the Treatment of Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a common disorder characterized by upper airway obstruction during sleep. To reduce the morbidity of OSA, sleep specialists have explored various methods of managing the condition, including manifold positive airway pressure (PAP) techniques and surgical procedures. Nasal obstruction can cause significant discomfort during sleep, and it is likely that improving nasal obstruction would enhance the quality of life and PAP compliance of OSA patients. Many reliable studies have offered evidence to support this assumption. However, few comprehensive guidelines for managing OSA through nasal surgery encompass all this evidence. In order to address this gap, the Korean Society of Otorhinolaryngology-Head and Neck Surgery (KORL-HNS) and the Korean Society of Sleep and Breathing designated a guideline development group (GDG) to develop recommendations for nasal surgery in OSA patients. Several databases, including OVID Medline, Embase, the Cochrane Library, and KoreaMed, were searched to identify all relevant papers using a predefined search strategy. The types of nasal surgery included septoplasty, turbinate surgery, nasal valve surgery, septorhinoplasty, and endoscopic sinus surgery. When insufficient evidence was found, the GDG sought expert opinions and attempted to fill the evidence gap. Evidence-based recommendations for practice were ranked according to the American College of Physicians’ grading system. The GDG developed 10 key action statements with supporting text to support them. Three statements are ranked as strong recommendations, three are only recommendations, and four can be considered options. The GDG hopes that this clinical practice guideline will help physicians make optimal decisions when caring for OSA patients. Conversely, the statements in this guideline are not intended to limit or restrict physicians’ care based on their experience and assessment of individual patients.

Solitary fibrous tumor in the temporalis muscle: a case report and literature review

Solitary fibrous tumor (SFT) is an infrequently occurring neoplasm most commonly observed in the pleura, but it can develop in the head and neck region in occasional cases. However, no reports have described SFT in the temporalis muscle. Herein, we present the first known case of SFT in the temporalis muscle. A 47-year-old man complained of a painless palpable mass on his right temple. Facial enhanced computed tomography identified a 4.0× 2.9× 1.4 cm mass presenting as a vascular tumor in the right temporalis muscle under the zygomatic arch. The mass was excised from the right temporalis muscle under general anesthesia. A histopathologic examination revealed that the mass was an SFT. No complications occurred after surgery, including functional disability or sensory loss. The patient was followed up for 3 months without complications. Although SFT in extrapulmonary regions is rare, it should be considered in the differential diagnosis of masses that occur in the temporal area.

Relationship between midfacial fractures and maxillary sinus pathology

Background@#Midfacial fractures frequently involve the maxillary sinus, leading to maxillary sinus pathology. We aimed to examine the incidence and contributing factors of maxillary sinus pathology in patients who underwent open reduction and internal fixation (ORIF) for midfacial fractures. @*Methods@#A retrospective analysis was conducted on patients who underwent ORIF for midfacial fractures at our department over the past 10 years. The incidence of maxillary sinus pathology was identified clinically and/or by computed tomography findings. Factors that significantly influenced the groups with and without maxillary sinus pathology were examined. @*Results@#The incidence of maxillary sinus pathology in patients who underwent ORIF for midfacial fractures was found to be 11.27%, with sinusitis being the most common pathology. Maxillary sinus pathology was significantly associated with the presence of a blowout fracture involving both the medial and the inferior orbital walls. Factors such as sex, age, diabetes mellitus, hypertension, smoking, inflammatory disease, follow-up period, use of absorbable plates, and use of titanium plates did not have a significant impact on the development of maxillary sinus pathology. @*Conclusion@#The incidence of maxillary sinus pathology in patients who underwent ORIF for midfacial fractures was relatively low, and in most cases, it resolved without the need for specific treatment. Consequently, there may not be a significant need for concern regarding postoperative maxillary sinus pathology.

Clinical outcomes and genotype-phenotype correlations in patients with complete and partial androgen insensitivity syndromes

Purpose@#Androgen insensitivity syndrome (AIS) is a rare X-linked recessive disorder caused by unresponsiveness to androgens because of mutations in the AR gene. Here, we investigated the clinical outcomes and molecular spectrum of AR variants in patients with AIS attending a single academic center. @*Methods@#This study included 19 patients with AIS who were confirmed by molecular analysis of AR. Clinical features and endocrinological findings were retrospectively collected, including presenting features, external genitalia, sex of rearing, timing of gonadectomy, pubertal outcomes, and sex hormone levels. Molecular analysis of AR was performed using Sanger, targeted gene panel, or whole-exome sequencing. @*Results@#Among all 19 patients, 14 (74%) were classified as having complete AIS (CAIS), whereas 5 (26%) had partial AIS (PAIS). All patients with CAIS, and 3 patients with PAIS were reared as female. One patient with CAIS manifested a mixed germ cell tumor at the age of 30 years. Molecular analysis of AR identified 19 sequence variants; 12 (63%) were previously reported, and the remaining 7 (37%) were novel. Missense mutations were the most common type (12 of 19, 63%), followed by small deletions, nonsense mutations, an insertion, and a splice site mutation. @*Conclusion@#Here, we describe the clinical outcomes and molecular characteristics of 19 Korean patients with AIS. Patients with PAIS manifested various degrees of masculinization of the external genitalia. Nonsense and frameshift mutations were frequent in patients with CAIS, whereas patients with PAIS harbored exclusively missense mutations.

2022 Clinical practice guidelines for central precocious puberty of Korean children and adolescents

The Committee of Central Precocious Puberty of Korean Pediatrics and Adolescents of the Korean Society of Pediatric Endocrinology has newly developed evidence-based 2022 clinical practice guidelines for central precocious puberty in Korean children and adolescents. These guidelines provide the grade of recommendations, which includes both the strength of recommendations and the level of evidence. In the absence of sufficient evidence, recommendations are based on expert opinion. These guidelines have been revised and supplement the previous guidelines "Clinical Guidelines for Precocious Puberty 2011," and are drawn from a comprehensive review of the latest domestic and international research and the grade of recommendation appropriate to the domestic situation. This review summarizes the newly revised guidelines into 8 key questions and 27 recommendations and consists of 4 sections: screening, diagnosis, treatment, and long-term outcome of central precocious puberty.

Molecular basis and genetic testing strategies for diagnosing 21-hydroxylase deficiency, including CAH-X syndrome

Congenital adrenal hyperplasia (CAH) is a group of autosomally recessive disorders that result from impaired synthesis of glucocorticoid and mineralocorticoid. Most cases (~95%) are caused by mutations in the CYP21A2 gene, which encodes steroid 21-hydroxylase. CAH patients manifest a wide phenotypic spectrum according to their degree of residual enzyme activity. CYP21A2 and its pseudogene (CYP21A1P) are located 30 kb apart in the 6q21.3 region and share approximately 98% of their sequences in the coding region. Both genes are aligned in tandem with the C4, SKT19, and TNX genes, forming 2 segments of the RCCX modules that are arranged as STK19-C4A-CYP21A1P-TNXA-STK19B-C4B-CYP21A2-TNXB. The high sequence homology between the active gene and pseudogene leads to frequent microconversions and large rearrangements through intergenic recombination. The TNXB gene encodes an extracellular matrix glycoprotein, tenascin-X (TNX), and defects in TNXB cause Ehlers-Danlos syndrome. Deletions affecting both CYP21A2 and TNXB result in a contiguous gene deletion syndrome known as CAH-X syndrome. Because of the high homology between CYP21A2 and CYP21A1P, genetic testing for CAH should include an evaluation of copy number variations, as well as Sanger sequencing. Although it poses challenges for genetic testing, a large number of mutations and their associated phenotypes have been identified, which has helped to establish genotype-phenotype correlations. The genotype is helpful for guiding early treatment, predicting the clinical phenotype and prognosis, and providing genetic counseling. In particular, it can help ensure proper management of the potential complications of CAH-X syndrome, such as musculoskeletal and cardiac defects. This review focuses on the molecular pathophysiology and genetic diagnosis of 21-hydroxylase deficiency and highlights genetic testing strategies for CAH-X syndrome.

Papillary Histiocytic and Mesothelial Hyperplasia of the Ovary Related to a Huge Uterus: A Case Report

Nodular histiocytic/mesothelial hyperplasia (NHMH) is a very rare condition. It is generally thought to be associated with repeated mechanical or chemical stimulation. This study reported NHMH with papillary growth pattern in the ovary following high-intensity focused ultrasound (HIFU) treatment for uterine leiomyoma and adenomyosis. A 48-year-old female, who had a history of undergoing HIFU treatment 7 times for adenomyosis and leiomyoma of the uterus 6 months ago, was referred to the hospital. After the hysterectomy and right salpingo-oophorectomy, the patient was confirmedly diagnosed with nodular histiocytic and mesothelial hyperplasia with the papillary growth pattern of the right ovary. This benign reactive inflammatory lesion of the mesothelium mimicking malignancy must be kept in mind to avoid unnecessary treatment.

Human Herpesvirus-8 Positive Multicentric Castleman’s Disease with Complete Response after Rituximab Monotherapy: A Case Report

Castleman’s disease is a rare non-neoplastic lymphoproliferative disorder of unknown origin. It is classified into unicentric or multicentric based on its anatomical distribution. Multicentric Castleman’s disease can be subdivided according to the presence of human herpesvirus-8 (HHV-8) infection. Castleman’s disease has a rare incidence, and HHV-8-positive multicentric Castleman’s disease is even rarer. There are several types of natural course for this disease, and the rapidly progressing type can lead to death within a few weeks, emphasizing the need for prompt diagnosis and treatment. We report a recent case from Korea, presenting with multiple lymphadenopathies, confirmed as HHV-8-positive multicentric Castleman’s disease through biopsy, and achieving complete response with rituximab monotherapy.

Bone Age Assessment Using Artificial Intelligence in Korean Pediatric Population: A Comparison of Deep-Learning Models Trained With Healthy Chronological and Greulich-Pyle Ages as Labels

Objective@#To develop a deep-learning-based bone age prediction model optimized for Korean children and adolescents and evaluate its feasibility by comparing it with a Greulich-Pyle-based deep-learning model. @*Materials and Methods@#A convolutional neural network was trained to predict age according to the bone development shown on a hand radiograph (bone age) using 21036 hand radiographs of Korean children and adolescents without known bone development-affecting diseases/conditions obtained between 1998 and 2019 (median age [interquartile range {IQR}], 9 [7–12] years; male:female, 11794:9242) and their chronological ages as labels (Korean model). We constructed 2 separate external datasets consisting of Korean children and adolescents with healthy bone development (Institution 1: n = 343;median age [IQR], 10 [4–15] years; male: female, 183:160; Institution 2: n = 321; median age [IQR], 9 [5–14] years; male:female, 164:157) to test the model performance. The mean absolute error (MAE), root mean square error (RMSE), and proportions of bone age predictions within 6, 12, 18, and 24 months of the reference age (chronological age) were compared between the Korean model and a commercial model (VUNO Med-BoneAge version 1.1; VUNO) trained with Greulich-Pyle-based age as the label (GP-based model). @*Results@#Compared with the GP-based model, the Korean model showed a lower RMSE (11.2 vs. 13.8 months; P = 0.004) and MAE (8.2 vs. 10.5 months; P = 0.002), a higher proportion of bone age predictions within 18 months of chronological age (88.3% vs. 82.2%; P = 0.031) for Institution 1, and a lower MAE (9.5 vs. 11.0 months; P = 0.022) and higher proportion of bone age predictions within 6 months (44.5% vs. 36.4%; P = 0.044) for Institution 2. @*Conclusion@#The Korean model trained using the chronological ages of Korean children and adolescents without known bone development-affecting diseases/conditions as labels performed better in bone age assessment than the GP-based model in the Korean pediatric population. Further validation is required to confirm its accuracy.

Two Cases of Life-Threatening Hemobilia Following Removal of Biliary Stents Treated with Covered Self-Expandable Metal Stents / 대한췌담도학회지

Biliary stent removal can cause hemobilia due to injury to the adjacent vessel, but it is rarely reported. If significant hemobilia occurs during stent removal, samesession covered self-expandable metal stent (CSEMS) insertion may be useful as a rescue or bridge therapy before angiography. Here, we report two cases of lifethreatening hemobilia following stent removal successfully treated by CSEMS. The first case was a Klatskin tumor bismuth type IV patient who required biliary stenting for resolving malignant biliary obstruction. The second case was a hepatocellular carcinoma patient who had undergone multiple transarterial chemoembolization and required biliary stents for liver abscess. In this situation, inserting a CSEMS at a higher level than the expected bleeding site and recognizing stenting as a temporary therapy with its limitations are important. Also, it is crucial to consider pre-procedural imaging in high-risk patients, and perform post-procedural imaging to evaluate for ongoing bleeding or vascular abnormalities.

Trends in Palate Surgery for Obstructive Sleep Apnea in Korea Over the Past 12 Years

Background and Objectives@#In the past, palate surgery, such as uvulopalatopharyngoplasty (UPPP), was widely performed to treat obstructive sleep apnea (OSA). However, since the introduction of reimbursement for positive airway pressure (PAP) therapy in 2018, it is believed that the frequency of these operations has significantly declined. Despite this, there are currently no definitive data to support this assertion. @*Methods@#We examined the number of palate operations conducted by utilizing medical statistical data from the Health Insurance Review and Assessment Service (HIRA) Bigdata Open portal. Within this system, we queried UPPP (Q2196), UPPP_complex (Q2195), and uvulectomy (Q2197), and collected data spanning from 2010 to 2021. The data were then analyzed according to hospital type, sex, and age groups. @*Results@#In total, 2,728 palate operations were performed in 2010; this number peaked at 4,330 cases in 2014, and then steadily decreased to 3,096 cases in 2021. Of the operations in 2010, 1,892 were conducted in general hospitals, while 836 took place in primary hospitals and clinics. However, by 2021, the number of operations performed in general hospitals had decreased to 1,002, while those performed in primary hospitals and clinics had increased to 2,093. The most common age group for these operations was 30–39 for men and 40–49 for women. Since 2019, the proportion of palate operations relative to the number of OSA patients has decreased. @*Conclusion@#The frequency of palate surgery in Korea started to decrease after 2014. Despite this, there was an increase in the number of these operations performed in hospitals and clinics, with middle-aged patients being the primary recipients. The ratio of palate operations to OSA patients has shown a notable decrease after the introduction of reimbursement of polysomnography and PAP therapy.

Frequent apocrine changes in pleomorphic adenoma with malignant transformation: a possible pre-malignant step in ductal carcinoma ex pleomorphic adenoma

Background@#The most common type of carcinoma ex pleomorphic adenoma (CPA) is histologically equivalent to salivary duct carcinoma, which has an apocrine phenotype. Invasive CPA is often accompanied by non-invasive or in situ carcinoma, an observation that suggests the presence of precursor lesions. The aim of this study was to identify candidate precursor lesions of CPA within pleomorphic adenoma (PA). @*Methods@#Eleven resected cases of CPA with residual PA and 17 cases of PA with atypical changes were subjected to immunohistochemistry (IHC) for p53, human epidermal growth factor receptor 2 (HER2), androgen receptor (AR), pleomorphic adenoma gene 1, gross cystic disease fluid protein-15 (GCDFP-15), and anti-mitochondrial antibody. @*Results@#Invasive or in situ carcinoma cells in all CPAs were positive for AR, GCDFP-15, and HER2. Atypical foci in PAs corresponded to either apocrine or oncocytic changes on the basis of their reactivity to AR, GCDFP-15, and anti-mitochondrial antibody. Atypical cells in PAs surrounding CPAs had an apocrine phenotype without HER2 expression. @*Conclusions@#Our study identified frequent apocrine changes in residual PAs in CPA cases, suggesting a possible precursor role of apocrine changes. We recommend the use of HER2 IHC in atypical PAs, and that clinicians take HER2 positivity into serious consideration.

Sex-Based Outcomes of P2Y12 Inhibitor Monotherapy After Three Months of Dual Antiplatelet Therapy in Patients Undergoing Percutaneous Coronary Intervention

Background@#In patients undergoing percutaneous coronary intervention (PCI) in the SMART-CHOICE trial, P2Y12 inhibitor monotherapy after three months of dual antiplatelet therapy (DAPT) achieved clinical outcomes comparable to those of 12 months of DAPT.Nonetheless, the effects of sex on these outcomes remain unknown. @*Methods@#This open-label, non-inferiority, randomized study, conducted in 33 hospitals in South Korea, included 2,993 patients undergoing PCI with drug-eluting stents. Patients were randomly assigned to receive DAPT (aspirin plus a P2Y12 inhibitor) for three months then P2Y12 inhibitor alone for nine months, or DAPT for the entire 12 months. The primary endpoints were major adverse cardiac and cerebrovascular events (a composite of all-cause death, myocardial infarction, or stroke) 12 months after the index procedure. The bleeding endpoints were Bleeding Academic Research Consortium (BARC) bleeding types 2 to 5. @*Results@#Of the patients, 795 (26.6%) were women, who were older and had a higher prevalence of hypertension, diabetes, and dyslipidemia than men. The sexes exhibited comparable primary endpoints (adjusted hazard ratio [HR], 0.93; 95% confidence interval [CI], 0.55–1.55; P = 0.770) and bleeding endpoints (adjusted HR, 1.07; 95% CI, 0.63–1.81; P = 0.811). P2Y12 inhibitor monotherapy vs DAPT was associated with lower risk of BARC type 2 to 5 bleeding in women (adjusted HR, 0.40; 95% CI, 0.16–0.98; P = 0.045) but the difference was not statistically significant when using the Bonferroni correction. The primary endpoints were similar between treatment groups in both sexes. @*Conclusion@#In both sexes undergoing PCI, P2Y12 inhibitor monotherapy after three months of DAPT achieved similar risks of the primary endpoints and the bleeding events compared with prolonged DAPT. Therefore, the benefits of early aspirin withdrawal with ongoing P2Y12 inhibitors may be comparable in women and men.

Comparison Between Fimasartan Versus Other Angiotensin Receptor Blockers in Patients With Heart Failure After Acute Myocardial Infarction

Background@#s: Fimasartan is the most recently developed, potent, and long-acting angiotensin II receptor blocker (ARB). However, data are limited regarding treatment effects of fimasartan in patients with heart failure. @*Methods@#Between 2010 and 2016, patients who underwent coronary revascularization for myocardial infarction (MI) with heart failure and prescription of ARB at hospital discharge were enrolled from the Korean nationwide medical insurance data. Clinical outcomes were compared between patients receiving fimasartan and those receiving other ARBs (candesartan, valsartan, losartan, telmisartan, olmesartan, and irbesartan). The primary outcome was a composite of all-cause death, recurrent MI, hospitalization for heart failure, and stroke. @*Results@#Of 2,802 eligible patients, fimasartan was prescribed to 124 patients (4.4%). During a median follow-up of 2.2 years (interquartile range, 1.0–3.9), 613 events of the primary outcome occurred. There was no significant difference in the primary outcome between patients receiving fimasartan and those receiving other ARBs (adjusted hazard ratio [HR], 0.82; 95% confidence interval [CI], 0.46–1.45). Compared with patients receiving other ARBs, those receiving fimasartan had comparable incidence of all-cause death (adjusted HR, 0.70; 95% CI, 0.30–1.63), recurrent MI (adjusted HR, 1.28; 95% CI, 0.49–3.34), hospitalization for heart failure (adjusted HR, 0.70; 95% CI, 0.27–1.84), and stroke (adjusted HR, 0.59; 95% CI, 0.18–1.96). @*Conclusion@#In this nationwide cohort, fimasartan, compared with other ARBs, had comparable treatment effects for a composite of all-cause death, recurrent MI, hospitalization for heart failure, and stroke in patients with heart failure after MI.

Characteristics of hard seltzer and their effect on the tooth surface / 대한구강보건학회지

Objectives@#To investigate the effect of commercially available hard seltzer on the tooth enamel surface. @*Methods@#Some commercially available hard seltzer were purchased at the market and the characteristics of the beverages were surveyed. Subsequently, Cloud hard seltzer mango was selected for the hard seltzer group (group 4), Jeju Samdasoo for the mineral water group (group 1), Coca-Cola for the cola group (group 2), and Cloud Original for the beer group (group 3). The specimens were immersed in the experimental beverage for 30 minutes, then the surface microhardness and surface condition of the specimens were evaluated. @*Results@#The average pH of the twelve types of hard seltzer in this study were 3.51±0.01 (before stirring) and 3.46±0.01 (after stirring). The pH of experimental beverage were 7.92±0.03 (group 1), 2.55±0.01 (group 2), 4.41±0.01 (group 3), and 3.31±0.01 (group 4). Paired t-test of the surface microhardness of enamel before and after beverage immersion found no significant difference in group 1 (P>0.05), but a significant difference was observed in groups 2, 3, and 4 (P<0.05). One way ANOVA of the surface microhardness change values (∆VHN, before - after immersion) among groups found a statistically significant difference between groups 1 and 3 (9.20±34.82 ∆VHN and 20.20±6.52 ∆VHN) and groups 2 and 4 (82.90±18.08 ∆VHN and 67.10±18.27 ∆VHN) (P<0.05).On scanning electron microscopy, hard seltzer group showed rough and ruined surface condition. @*Conclusions@#This study found a risk of dental erosion due to the low pH of hard seltzer. Therefore, it is suggested that when ingesting hard seltzer, dental erosion should be considered for oral health.

Professional self-concept, self-leadership, job stress and fatigue on clinical competence of dental hygienists / 대한구강보건학회지

Objectives@#This study examines the relationship of dental hygienists’ professional self-concept, self-leadership, job stress, and fatigue with their clinical competence in order to identify factors that can improve clinical competence. This study is intended to provide basic information to develop educational programs for dental hygienist’s clinical competence. @*Methods@#The self-administered questionnaire survey was conducted with 243 dental hygienists working at dental clinics in Gwangju and Jeonnam from August 14, 2017 to September 9, 2017.The data regarding the general characteristics, professional self-concept, self-leadership, job stress and fatigue, and clinical competence were collected, and analyzed through independent t-tests, one-way analysis of variance (ANOVA), Pearson’s correlation coefficient, and multiple regression analysis using the SPSS Windows ver. 22.0. @*Results@#High professional self-concept (r=0.54) and self-leadership(r=0.48) were associated with high clinical competence. High self-leadership (r=0.53) was associated with high professional selfconcept. High fatigue(r=―0.21) was associated with low professional self-concept(P<0.01). The highest factor influencing clinical competence was professional self-concept, followed by selfleadership, total clinical experience, education level, and fatigue (P<0.05). @*Conclusions@#Based on the findings, it is necessary to develop educational programs which can improve autonomy and develop professionalism to enhance clinical competence in consideration of work experience and educational levels in dental hygienists.

Image fusion technique using flat panel detector rotational angiography for transvenous embolization of intracranial dural arteriovenous fistula

Precise evaluation of the feeders, fistulous points, and draining veins plays a key role for successful embolization of intracranial dural arteriovenous fistulas (DAVF). Digital subtraction angiography (DSA) is a gold standard diagnostic tool to assess the exact angioarchitecture of DAVFs. With the advent of new image postprocessing techniques, we lately have been able to apply image fusion techniques with two different image sets obtained with flat panel detector rotational angiography. This new technique can provide additional and better pretherapeutic information of DAVFs over the conventional 2D and 3D angiographies. In addition, it can be used during the endovascular treatment to help the accurate and precise navigation of the microcatheter and microguidwire inside the vessels and identify the proper location of microcatheter in the targeted shunting pouch. In this study, we briefly review the process of an image fusion technique and introduce our clinical application for treating DAVFs, especially focused on the transvenous embolization.