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Objective: This study aimed to establish an academic basis for using a computed tomography (CT) model for predicting osteoporosis in the clinical setting by illustrating the effectiveness of morphometric texture analysis. We introduce texture analysis and quantitative approaches using CT Hounsfield units (HU) to screen osteoporosis. Method: From March 6th, 2013, to August 11th, 2020, a total of 4,333 cases (1,766 patients) were included in the study. After applying exclusion criteria concerning the patient status and scan interval between CT and DXA, we selected only 1,647 samples (736 patients) and analyzed both their CT and DXA bone mineral density (BMD) results. BMD was measured in the femoral neck and L1 spine body. A region of interest (ROI) was extracted from each patient’s CT as the maximum trabecular area of the L1 spine body and femoral neck. A total of 45 texture features were extracted from every ROI using gray-level co-occurrence matrices. Machine-learning techniques, including linear regression (LR) and artificial neural network (ANN), were applied to predict BMD. Results: We assigned samples to (1) Set 1 (857 lumbar spine samples in chest model, L1 spine DXA BMD), (2) Set 2 (392 lumbar spine samples in lumbar spine CT model, L1 spine DXA BMD), (3) Set 3 (1,249 lumbar spine samples in both chest and lumbar spine CT model, L1 spine DXA BMD), (4) Set 4 (398 femoral neck samples in hip and pelvis CT model, femoral neck DXA BMD), and (5) Set 5 (a total of 1,647 samples). When we applied LR, the correlation coefficients between estimated and reference values for Sets 1, 2, 3, and 4 were 0.783, 0.784, 0.757, and 0.652, respectively. For total samples (Set 5), LR and ANN provided correlation coefficients of 0.707 and 0.782, respectively. Conclusion: The modality using morphometric texture analysis with CT HU can be an additional diagnostic tool for osteoporosis and an alternative for DXA.

There are no clinical studies about treatment of distal tibia fractures using far cortical locking (FCL) screws, even though it has been shown to be superior to standard locking screws in biomechanical studies. We compared the efficacy of FCL screws to that of traditional locking screws. Twenty-five distal tibia fractures were treated with minimally invasive plate osteosynthesis using traditional locking screws, whereas 20 were treated using FCL screws. We retrospectively compared time taken for callus formation and radiographic bone union between 2 groups. The effect of age, sex, diabetes, and smoking history on bone healing was analyzed. Complications were also noted. As a result, there was no significant difference in age (p = .292), sex (p = 1.0), diabetes (p = 1.0), or smoking history (p = .704) between 2 groups. Time to callus formation was 77.5 days in the FCL group, and 96 days in the traditional group (p = .023). Average time to bone union was 134.8 days, and 163.1 days in the FCL group and the traditional group, respectively (p = .017). There was one case of screw loosening in the FCL group, and one case of screw breakage in the traditional group. This study suggests that FCL screws promote quicker healing of distal tibia fractures than traditional locking screws.

The aim of this study was to develop evidence-based recommendations for determining the surgical extent in patients with locally invasive differentiated thyroid cancer (DTC). Locally invasive DTC with gross extrathyroidal extension invading surrounding anatomical structures may lead to several functional deficits and poor oncological outcomes. At present, the optimal extent of surgery in locally invasive DTC remains a matter of debate, and there are no adequate guidelines. On October 8, 2021, four experts searched the PubMed, Embase, and Cochrane Library databases; the identified papers were reviewed by 39 experts in thyroid and head and neck surgery. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the quality of evidence, and to develop and report recommendations. The strength of a recommendation reflects the confidence of a guideline panel that the desirable effects of an intervention outweigh any undesirable effects, across all patients for whom the recommendation is applicable. After completing the draft guidelines, Delphi questionnaires were completed by members of the Korean Society of Head and Neck Surgery. Twenty-seven evidence-based recommendations were made for several factors, including the preoperative workup; surgical extent of thyroidectomy; surgery for cancer invading the strap muscles, recurrent laryngeal nerve, laryngeal framework, trachea, or esophagus; and surgery for patients with central and lateral cervical lymph node involvement. Evidence-based guidelines were devised to help clinicians make safer and more efficient clinical decisions for the optimal surgical treatment of patients with locally invasive DTC.

The Ordovician succession of the Korean Peninsula is part of the Cambro-Ordovician Joseon Supergroup exposed in the Taebaeksan Basin of South Korea and the Pyeongnam Basin of North Korea. This review summarizes the advances made on these successions over the past two decades, focusing on the Taebaeksan Basin. The Ordovician succession in the Taebaeksan Basin comprises the Taebaek, Yeongwol, Yongtan, Pyeongchang and Mungyeong groups, of which the Taebaek and Yeongwol groups have been studied in detail. These strata are mixed carbonate–siliciclastic deposits formed in peritidal to deep-subtidal environments. Sedimentological and palaeontological studies show that the Korean Ordovician succession represents local variations of the Great Ordovician Biodiversification Event, exemplified by reef evolution, changes in sedimentary systems and changes in invertebrate fossil assemblages. Recent studies of the Yongtan, Pyeongchang and Mungyeong groups have demonstrated that these units are important for understanding the tectonic evolution of the Taebaeksan Basin. The Ordovician strata in the Taebaek Group are generally similar to those of the Pyeongnam Basin and North China; however, the Upper Ordovician–Devonian strata between the two Korean basins show palaeontological affinities to those of South China, perhaps recording the Permo-Triassic collision between the Sino-Korean (North China) and South China blocks.

Throughout an individual’s lifetime, genomic alterations accumulate in somatic cells1–11. However, the mutational landscape induced by retrotransposition of long interspersed nuclear element-1 (L1), a widespread mobile element in the human genome12–14, is poorly understood in normal cells. Here we explored the whole-genome sequences of 899 single-cell clones established from three different cell types collected from 28 individuals. We identified 1,708 somatic L1 retrotransposition events that were enriched in colorectal epithelium and showed a positive relationship with age. Fingerprinting of source elements showed 34 retrotransposition-competent L1s. Multidimensional analysis demonstrated that (1) somatic L1 retrotranspositions occur from early embryogenesis at a substantial rate, (2) epigenetic on/off of a source element is preferentially determined in the early organogenesis stage, (3) retrotransposition-competent L1s with a lower population allele frequency have higher retrotransposition activity and (4) only a small fraction of L1 transcripts in the cytoplasm are finally retrotransposed in somatic cells. Analysis of matched cancers further suggested that somatic L1 retrotransposition rate is substantially increased during colorectal tumourigenesis. In summary, this study illustrates L1 retrotransposition-induced somatic mosaicism in normal cells and provides insights into the genomic and epigenomic regulation of transposable elements over the human lifetime.

to investigate the association between the lateral femoral condylar ratio (LFCR), the posterior tibial slope (PTS), and injury of the anterolateral ligament (ALL).Inclusion criteria were patients with acute anterior cruciate ligament (ACL) tear after noncontact injury during sports from October 1997 to May 2021. The LFCR and PTS were measured, and injury of the ALL was evaluated. Patients were divided into 2 groups: isolated ACL tear (isolated group) and combined ACL with ALL tear (combined group). The LFCR and PTS were compared between the isolated and combined groups. For each risk factor, the receiver operating characteristic curve, the area under the curve (AUC), and its 95% confidence interval (CI) were calculated to determine the cutoff for detecting increased risk of ALL injury.There were 83 patients in the isolated group and 176 patients in the combined group. Demographics of the 2 groups did not differ significantly. The LFCR was significantly larger in the combined group than in the isolated group (P = .000). The PTS did not differ between the two groups (P = .405). The LFCR (odds ratio [OR] = 1.58; P = .000) was a significant factor. Age, body mass index, and PTS were not associated with an ALL injury. The AUC (0.79; 95% CI, 0.74-0.85) for the LFCR had a sensitivity of 73% and specificity of 76% to predict an ALL rupture. The calculated cutoff of 64.5 was associated with an increased risk for ALL rupture (OR = 8.65; 95% CI, 4.73-15.81) when compared with the isolated group.An increased LFCR was associated with the ALL injury. However, increased PTS was not associated with ALL injury. These findings need to be considered for clinicians in treating ACL tear patients at risk for an ALL injury.III, retrospective comparative prognostic trial.

Objectives : To confirm both efficiency and sustainability of algal growth inhibition, various laboratory-scale experiments were conducted and the growth inhibitory effect of Microcystis aeruginosa (M. aeruginosa) was investigated through ultrasonic re-irradiation during the regrowth period after the first ultrasound irradiation.Methods : Experiments with different times of irradiation [i.e., control group A (0 hr), experimental group B (2 hr) applied with only the first ultrasound irradiation, and experimental group C (0.5 hr), D (1 hr), and E (1.5 hr) applied with both first and second irradiations] were performed.Results and Discussion : As a result of both Chlorophyll-a (Chl-a) concentration and cell number of M. aeruginosa, the experimental group (B) with only first ultrasound irradiation (2 hr) displayed rapid regrowth of algae after initial decrease whereas the experimental group (C, D, and E) with both first ultrasound irradiation (2 hr) and second ultrasound irradiation (0.5 hr, 1 hr, and 1.5 hr) confirmed the delay of algae regrowth. Based on the specific growth rate constant (µ) and first order decay rate constant (k), algal growth from the experimental groups (C, D, E) with the secondary ultrasound irradiation was more significantly inhibited due to repetitive inactivation of algae growth. According to the SEM and TEM results, damages to algae cells were clearly observed under the influence of ultrasound, and both decrease in gas vesicles and rupture of cell membrane in M. aeruginosa were also monitored.Conclusion : Through this study, the algae growth inhibitory effect by ultrasonic irradiations was confirmed, and the re-irradiation of ultrasound contributed to the repetitive inactivation of algae growth, indicating that the second ultrasonic irradiation time required to inhibit algal regrowth can be reduced compared to the first irradiation. Therefore, periodic ultrasonic irradiation is required for long-term inhibition of algae growth in stagnant waters, but the appropriate frequency of ultrasonic irradiation may vary depending on the influence of various complex factors such as the size of the stagnant waters, the frequency of algal blooms, water temperature, light irradiation, nutrients, flow rate, etc. Finally, many field studies under various conditions are warranted to establish an optimized ultrasound irradiation protocol.

Purpose: We investigated the current status of imaging studies for pediatric blunt cervical spine injury, and applied 3 clinical decision rules to children with blunt trauma of the head or neck in a pediatric emergency center in Korea. The rules included National Emergency X-Radiography Utilization Study (NEXUS) criteria, Canadian Cervical Spine Rule, and Pediatric Emergency Care Applied Research Network risk factors.Methods: This was a retrospective study conducted on 399 children aged 15 years or younger who visited the center after the blunt trauma, and underwent cervical spine radiographs from January 2020 through December 2021. We examined the clinical characteristics per age groups (0-1, 2-5, 6-12, and 13-15 years). Using the 3 rules, we selected children with a potential need for imaging studies (PNI). For this purpose, we analyzed the absence of low-risk variables and the presence of high-risk variables. Predictive performances of the rules were measured for the imaging-confirmed cervical spine injury.Results: The study population (n = 399) had a median age of 5.0 years (interquartile range, 2.0-9.0) and a 64.2% boys’ proportion. Fall (36.6%) was the most common injury mechanism. Two children had the cervical spine injuries. As per NEXUS criteria, Canadian Cervical Spine Rule, and Pediatric Emergency Care Applied Research Network risk factors, 72 (18.0%), 289 (72.4%), and 74 children (18.5%) were classified as those with PNI, respectively. Resultantly, 291 children (72.9%) were classified as having PNI whereas the other 108 (27.1%) were deemed to undergo unnecessary imaging. The 3 rules had nearly 100% sensitivity and negative predictive value, except a 50% sensitivity of NEXUS criteria.Conclusion: Imaging studies can be minimized for children with blunt trauma of the head or neck who are deemed without PNI per the 3 current clinical decision rules. More elaborate criteria are needed to make a timely diagnosis.

Background: Hemorrhagic Moyamoya disease (MMD) is a common subtype of MMD in adult patients, especially in East Asian countries. To our knowledge, current studies regarding factors affecting the prognosis in patients with hemorrhagic MMD is lacking. This study aimed to determine the potential prognostic factors for hemorrhagic MMD.Methods: This retrospective study reviewed patients with hemorrhagic MMD diagnosed at our hospital between June 2011 and June 2021. Patient outcome was measured at discharge using the extended Glasgow outcome scale (GOSE). Prognostic factors were assessed by multivariate logistic regression analysis.Results: Patients discharged with worst outcomes (GOSE 1 and 2) had significantly lower initial Glasgow coma scale (GCS) scores (5.9 ± 3.1 vs. 10.3 ± 3.7; P = 0.002) and were associated with more severe intraventricular hemorrhage (IVH) (P = 0.007), and IVH-related hydrocephalus requiring extraventricular drain (EVD) insertion was more common (n = 12 vs. n = 7; P = 0.001). The multivariate analysis showed that IVH-related hydrocephalus requiring EVD placement (OR 8.256, 95% CI 0.996–68.450; P = 0.016) and low initial GCS scores (OR 0.644; 95% CI 0.465–0.892; P = 0.008) were independent risk factors for unfavorable outcomes (GOSE 1–4) in patients with hemorrhagic MMD.Conclusion: This study analyzed several potential prognostic factors for patients with hemorrhagic MMD. Low initial GCS scores and IVH-related hydrocephalus requiring EVD insertion were related to unfavorable outcomes.

Background Lip lifting is a widely accepted and efficient surgical procedure for volumizing the upper lip to achieve a more youthful appearance. A previous study by Hwang et al. identified the lip-related ratios most preferred by Koreans: a lip height-to-width ratio (LTW) of 0.4, an upper-to-lower vermilion ratio (ULR) of 0.8, and an upper vermilion thickness-to-upper lip height ratio (VUL) of 0.5. The current study investigated whether the attractive lip ratio favored by Koreans could be obtained with central upper lip lift surgery.Methods This retrospective chart review included South Korean patients who underwent central lip lifts between 2015 and 2019 at a single center. The LTW, ULR, VUL, and columellar-labial angle were measured using the patients’ preoperative and postoperative clinical photographs.Results A total of 87 patients underwent central lip lifts. Before surgery, the mean LTW was 0.34, the mean ULR was 0.76, and the mean VUL was 0.30. After surgery, the LTW increased to an average of 0.39, the ULR increased to 0.84, and the VUL increased to 0.393. The patients’ postoperative ratio values were close to the attractive lip ratio values proposed by Hwang et al. The average columellar-labial angle decreased from 101.59° to 95.04°, and therefore did not interfere with the aesthetic relationship between the nose and lips.Conclusions The central lip lift was an efficient cosmetic technique that provided the Korean ideal shape for attractive lips.

This study aims to present the spread of a smart green city model centered on water and waste management among Jeju's environmental policies, and to provide sustainable green business services. To this end, a frame was introduced for the smart green policy at the SDGs and circular economy level, and a strategy was proposed after creating a problem map for linking with the upper plan for smart green policy at the central government and Jeju Island level and solving regional problems. Furthermore, the spatial linkage of Jeju with SDGs and sustainable green governance through improving resident-centered global cooperation were illustrated.

An accessory parotid gland is salivary gland tissue that exists separately anterior to the parotid gland. Since malignant tumors can be found in about 50% of accessory parotid tumors, the standard treatment is radical resection via externa l approach. However, with the development of endoscopic surgery in the head and neck field, the transoral approach using an endoscope is also being tried. Although this technique could remove benign tumors without skin incision, there may be cases where removal via transoral approach may prove difficult. The authors experienced a case of failed attempt to remove pleomorphic adenoma in the accessory parotid gland via transoral approach in a 24-year-old male patient. We analyzed the causes of surgical failure in this case from various perspectives. We believe that our lessons from this failed case could help determine the appropriate surgical indications of transoral approach in the accessory parotid gland tumor.

Endotracheal intubation is often necessary in the course of animal experiments, especially in craniofacial surgery. However, endotracheal intubation can be a major burden in this context. The authors performed simple and cost-saving method using a 200 μL yellow micropipette tip, and the success of this method was demonstrated by X-ray and autopsy. We used a total of 30 rats. After the rats were fixed with a plaster, the trachea and vocal cords were visualized with the tongue pulled back. Under direct visualization of the vocal cords, a curving micropipette tip was advanced into the trachea. This method can be learned quickly and applied successfully by general experimenters. We successfully intubated all 30 rats without any complications. The success rate of micropipette tip intubation was 100%. This procedure was performed by one experimenter within 2 to 3 minutes after induction of anesthesia. We demonstrated its superiority by X-ray and autopsy. Herein, we describe endotracheal intubation of rats using micropipette tips. To the best of our knowledge, this method is novel and represents the simplest and most efficient means of intubation in rats, providing an alternative to conventional endotracheal intubation.