Objective: To establish local diagnostic reference levels (DRLs) for pediatric neck CT based on age, weight, and water-equivalent diameter (WED) across multiple university hospitals in South Korea. Materials and Methods: This retrospective study analyzed pediatric neck CT examinations from nine university hospitals, involving patients aged 0–18 years. Data were categorized by age, weight, and WED, and radiation dose metrics, including volume CT dose index (CTDIvol) and dose length product, were recorded. Data retrieval and analysis were conducted using a commercially available dose-management system (Radimetrics, Bayer Healthcare). Local DRLs were established following the International Commission on Radiological Protection guidelines, using the 75th percentile as the reference value. Results: A total of 1159 CT examinations were analyzed, including 169 scans from Institution 1, 132 from Institution 2, 126 from Institution 3, 129 from Institution 4, 128 from Institution 5, 105 from Institution 6, 162 from Institution 7, 127 from Institution 8, and 81 from Institution 9. Radiation dose metrics increased with age, weight, and WED, showing significant variability both within and across institutions. For patients weighing less than 10 kg, the DRL for CTDIvol was 5.2 mGy. In the 10–19 kg group, the DRL was 5.8 mGy; in the 20–39 kg group, 7.6 mGy; in the 40–59 kg group, 11.0 mGy; and for patients weighing 60 kg or more, 16.2 mGy. DRLs for CTDIvol by age groups were as follows: 5.3 mGy for infants under 1 year, 5.7 mGy for children aged 1–4 years, 7.6 mGy for ages 5–9 years, 11.2 mGy for ages 10–14 years, and 15.6 mGy for patients 15 years or older. Conclusion Local DRLs for pediatric neck CT were established based on age, weight, and WED across nine university hospitals in South Korea.

Objective: To establish local diagnostic reference levels (DRLs) for pediatric neck CT based on age, weight, and water-equivalent diameter (WED) across multiple university hospitals in South Korea. Materials and Methods: This retrospective study analyzed pediatric neck CT examinations from nine university hospitals, involving patients aged 0–18 years. Data were categorized by age, weight, and WED, and radiation dose metrics, including volume CT dose index (CTDIvol) and dose length product, were recorded. Data retrieval and analysis were conducted using a commercially available dose-management system (Radimetrics, Bayer Healthcare). Local DRLs were established following the International Commission on Radiological Protection guidelines, using the 75th percentile as the reference value. Results: A total of 1159 CT examinations were analyzed, including 169 scans from Institution 1, 132 from Institution 2, 126 from Institution 3, 129 from Institution 4, 128 from Institution 5, 105 from Institution 6, 162 from Institution 7, 127 from Institution 8, and 81 from Institution 9. Radiation dose metrics increased with age, weight, and WED, showing significant variability both within and across institutions. For patients weighing less than 10 kg, the DRL for CTDIvol was 5.2 mGy. In the 10–19 kg group, the DRL was 5.8 mGy; in the 20–39 kg group, 7.6 mGy; in the 40–59 kg group, 11.0 mGy; and for patients weighing 60 kg or more, 16.2 mGy. DRLs for CTDIvol by age groups were as follows: 5.3 mGy for infants under 1 year, 5.7 mGy for children aged 1–4 years, 7.6 mGy for ages 5–9 years, 11.2 mGy for ages 10–14 years, and 15.6 mGy for patients 15 years or older. Conclusion Local DRLs for pediatric neck CT were established based on age, weight, and WED across nine university hospitals in South Korea.

Objective: To establish local diagnostic reference levels (DRLs) for pediatric neck CT based on age, weight, and water-equivalent diameter (WED) across multiple university hospitals in South Korea. Materials and Methods: This retrospective study analyzed pediatric neck CT examinations from nine university hospitals, involving patients aged 0–18 years. Data were categorized by age, weight, and WED, and radiation dose metrics, including volume CT dose index (CTDIvol) and dose length product, were recorded. Data retrieval and analysis were conducted using a commercially available dose-management system (Radimetrics, Bayer Healthcare). Local DRLs were established following the International Commission on Radiological Protection guidelines, using the 75th percentile as the reference value. Results: A total of 1159 CT examinations were analyzed, including 169 scans from Institution 1, 132 from Institution 2, 126 from Institution 3, 129 from Institution 4, 128 from Institution 5, 105 from Institution 6, 162 from Institution 7, 127 from Institution 8, and 81 from Institution 9. Radiation dose metrics increased with age, weight, and WED, showing significant variability both within and across institutions. For patients weighing less than 10 kg, the DRL for CTDIvol was 5.2 mGy. In the 10–19 kg group, the DRL was 5.8 mGy; in the 20–39 kg group, 7.6 mGy; in the 40–59 kg group, 11.0 mGy; and for patients weighing 60 kg or more, 16.2 mGy. DRLs for CTDIvol by age groups were as follows: 5.3 mGy for infants under 1 year, 5.7 mGy for children aged 1–4 years, 7.6 mGy for ages 5–9 years, 11.2 mGy for ages 10–14 years, and 15.6 mGy for patients 15 years or older. Conclusion Local DRLs for pediatric neck CT were established based on age, weight, and WED across nine university hospitals in South Korea.

Objective: To establish local diagnostic reference levels (DRLs) for pediatric neck CT based on age, weight, and water-equivalent diameter (WED) across multiple university hospitals in South Korea. Materials and Methods: This retrospective study analyzed pediatric neck CT examinations from nine university hospitals, involving patients aged 0–18 years. Data were categorized by age, weight, and WED, and radiation dose metrics, including volume CT dose index (CTDIvol) and dose length product, were recorded. Data retrieval and analysis were conducted using a commercially available dose-management system (Radimetrics, Bayer Healthcare). Local DRLs were established following the International Commission on Radiological Protection guidelines, using the 75th percentile as the reference value. Results: A total of 1159 CT examinations were analyzed, including 169 scans from Institution 1, 132 from Institution 2, 126 from Institution 3, 129 from Institution 4, 128 from Institution 5, 105 from Institution 6, 162 from Institution 7, 127 from Institution 8, and 81 from Institution 9. Radiation dose metrics increased with age, weight, and WED, showing significant variability both within and across institutions. For patients weighing less than 10 kg, the DRL for CTDIvol was 5.2 mGy. In the 10–19 kg group, the DRL was 5.8 mGy; in the 20–39 kg group, 7.6 mGy; in the 40–59 kg group, 11.0 mGy; and for patients weighing 60 kg or more, 16.2 mGy. DRLs for CTDIvol by age groups were as follows: 5.3 mGy for infants under 1 year, 5.7 mGy for children aged 1–4 years, 7.6 mGy for ages 5–9 years, 11.2 mGy for ages 10–14 years, and 15.6 mGy for patients 15 years or older. Conclusion Local DRLs for pediatric neck CT were established based on age, weight, and WED across nine university hospitals in South Korea.

Objective: To establish local diagnostic reference levels (DRLs) for pediatric neck CT based on age, weight, and water-equivalent diameter (WED) across multiple university hospitals in South Korea. Materials and Methods: This retrospective study analyzed pediatric neck CT examinations from nine university hospitals, involving patients aged 0–18 years. Data were categorized by age, weight, and WED, and radiation dose metrics, including volume CT dose index (CTDIvol) and dose length product, were recorded. Data retrieval and analysis were conducted using a commercially available dose-management system (Radimetrics, Bayer Healthcare). Local DRLs were established following the International Commission on Radiological Protection guidelines, using the 75th percentile as the reference value. Results: A total of 1159 CT examinations were analyzed, including 169 scans from Institution 1, 132 from Institution 2, 126 from Institution 3, 129 from Institution 4, 128 from Institution 5, 105 from Institution 6, 162 from Institution 7, 127 from Institution 8, and 81 from Institution 9. Radiation dose metrics increased with age, weight, and WED, showing significant variability both within and across institutions. For patients weighing less than 10 kg, the DRL for CTDIvol was 5.2 mGy. In the 10–19 kg group, the DRL was 5.8 mGy; in the 20–39 kg group, 7.6 mGy; in the 40–59 kg group, 11.0 mGy; and for patients weighing 60 kg or more, 16.2 mGy. DRLs for CTDIvol by age groups were as follows: 5.3 mGy for infants under 1 year, 5.7 mGy for children aged 1–4 years, 7.6 mGy for ages 5–9 years, 11.2 mGy for ages 10–14 years, and 15.6 mGy for patients 15 years or older. Conclusion Local DRLs for pediatric neck CT were established based on age, weight, and WED across nine university hospitals in South Korea.

Background: Atopic dermatitis (AD) is a chronic relapsing inflammatory skin disease.Although murine studies have demonstrated that type 2 innate lymphoid cells (ILCs) mediate type 2 skin inflammation, their role in skin fibrosis in AD remains unclear. This study investigated whether type 2 ILCs are involved in skin fibrosis using an AD-like murine model. Methods: C57BL/6 mice were treated epicutaneously with Aspergillus fumigatus (Af) for 5 consecutive days per week for 5 weeks to induce skin fibrosis. Mature lymphocyte deficient Rag1−/− mice were also used to investigate the role of type 2 ILCs in skin fibrosis. Results: The clinical score and transepidermal water loss (TEWL) were significantly higher in the AD group than in the control group. The AD group also showed significantly increased epidermal and dermal thicknesses and significantly higher numbers of eosinophils, neutrophils, mast cells, and lymphocytes in the lesional skin than the control group. The lesional skin of the AD group showed increased stain of collagen and significantly higher levels of collagen than the control group (10.4 ± 2.2 µg/mg vs. 1.6 ± 0.1 µg/mg, P < 0.05). The AD group showed significantly higher populations of type 2 ILCs in the lesional skin compared to the control group (0.08 ± 0.01% vs. 0.03 ± 0.01%, P < 0.05). These findings were also similar with the AD group of Rag1−/− mice compared to their control group. Depletion of type 2 ILCs with anti-CD90.2 monoclonal antibodies significantly improved clinical symptom score, TEWL, and infiltration of inflammatory cells, and significantly decreased levels of collagen were observed in the AD group of Rag1−/− mice (1.6 ± 0.0 μg/mg vs. 4.5 ± 0.3 μg/mg, P < 0.001). Conclusion In the Af-induced AD-like murine model, type 2 ILCs were elevated, with increased levels of collagen. Additionally, removal of type 2 ILCs resulted in decreased collagen levels and improved AD-like pathological findings. These findings suggest that type 2 ILCs play a role in the mechanism of skin fibrosis in AD.

A 74-year-old woman presented with a progressive pattern of dysphagia and odynophagia over one month.Magnetic resonance imaging of the neck revealed diffuse swelling from the tongue base and velum extending to the posterior pharyngeal wall. Instrumental evaluation of swallowing showed decreased peristalsis in the esophageal phase, accompanied by severe swelling of the hypopharynx, which limited laryngeal elevation and subsequently led to decreased bolus clearance and impaired airway protection. Laboratory studies revealed a 61% increase in eosinophil count. An endoscopic biopsy of the esophagus confirmed the diagnosis of eosinophilic esophagitis. The patient was administered intravenous dexamethasone at a total dosage of 45 mg/day for 7 days. The eosinophil count dropped to the normal range, correlating with the improvement in dysphagia and aspiration. Eosinophilic esophagitis often presents in children and rarely involves the oropharyngeal structures. Due to its specific involvement of the esophagus, it seldom leads to aspiration. By contrast, the extension of eosinophilic inflammation from the esophagus to the oropharynx in this case resulted in atypical symptoms such as odynophagia and aspiration. The therapeutic approach can be challenging due to the difficulty in administering topical steroids, which are often the treatment of choice. However, the condition showed an excellent response to intravenous steroid therapy.

Purpose: This study aimed to develop an animal model suitable for coronectomy research. Materials and Methods: Eighteen Sprague-Dawley rats were divided into six groups: incisor control (InC), incisor flap (InF), incisor non-flap (InNF), molar control (MC), molar flap (MF), and molar non-flap (MNF). Coronectomy was not performed in the control groups (InC and MC). In the incisor (In) groups, coronectomy was performed on the mandibular incisors, with flap elevation in the InF group and without flap elevation in the InNF group. In the molar (M) groups, coronectomy was performed on the maxillary first molar, with flap elevation in the MF group and without flap elevation in the MNF group. The incisor groups were sacrificed on day 7, and the molar groups on days 7 and 14. Clinical healing, tooth movement, and histological and immunohistochemical analyses were performed. Results: InF and InNF groups showed tooth eruption similar to or the same as that before coronectomy, whereas the MF and MNF groups’ roots moved slowly. In InF and InNF groups, the pulp at the maturation zone was mineralized, but apical pulp vitality was maintained. MF and MNF groups showed bacterial infection and inflammation on day 7, with mineralization on day 14; however, apical pulp vitality was maintained. The MF group showed varied healing patterns, whereas the MNF group had consistent results across individuals. Conclusion Both incisors and molars are meaningful models for coronectomy. However, for consistent experimental results, coronectomy without flap elevation on the maxillary first molar is recommended.

Purpose: This study aimed to develop an animal model suitable for coronectomy research. Materials and Methods: Eighteen Sprague-Dawley rats were divided into six groups: incisor control (InC), incisor flap (InF), incisor non-flap (InNF), molar control (MC), molar flap (MF), and molar non-flap (MNF). Coronectomy was not performed in the control groups (InC and MC). In the incisor (In) groups, coronectomy was performed on the mandibular incisors, with flap elevation in the InF group and without flap elevation in the InNF group. In the molar (M) groups, coronectomy was performed on the maxillary first molar, with flap elevation in the MF group and without flap elevation in the MNF group. The incisor groups were sacrificed on day 7, and the molar groups on days 7 and 14. Clinical healing, tooth movement, and histological and immunohistochemical analyses were performed. Results: InF and InNF groups showed tooth eruption similar to or the same as that before coronectomy, whereas the MF and MNF groups’ roots moved slowly. In InF and InNF groups, the pulp at the maturation zone was mineralized, but apical pulp vitality was maintained. MF and MNF groups showed bacterial infection and inflammation on day 7, with mineralization on day 14; however, apical pulp vitality was maintained. The MF group showed varied healing patterns, whereas the MNF group had consistent results across individuals. Conclusion Both incisors and molars are meaningful models for coronectomy. However, for consistent experimental results, coronectomy without flap elevation on the maxillary first molar is recommended.

Purpose: This study aimed to develop an animal model suitable for coronectomy research. Materials and Methods: Eighteen Sprague-Dawley rats were divided into six groups: incisor control (InC), incisor flap (InF), incisor non-flap (InNF), molar control (MC), molar flap (MF), and molar non-flap (MNF). Coronectomy was not performed in the control groups (InC and MC). In the incisor (In) groups, coronectomy was performed on the mandibular incisors, with flap elevation in the InF group and without flap elevation in the InNF group. In the molar (M) groups, coronectomy was performed on the maxillary first molar, with flap elevation in the MF group and without flap elevation in the MNF group. The incisor groups were sacrificed on day 7, and the molar groups on days 7 and 14. Clinical healing, tooth movement, and histological and immunohistochemical analyses were performed. Results: InF and InNF groups showed tooth eruption similar to or the same as that before coronectomy, whereas the MF and MNF groups’ roots moved slowly. In InF and InNF groups, the pulp at the maturation zone was mineralized, but apical pulp vitality was maintained. MF and MNF groups showed bacterial infection and inflammation on day 7, with mineralization on day 14; however, apical pulp vitality was maintained. The MF group showed varied healing patterns, whereas the MNF group had consistent results across individuals. Conclusion Both incisors and molars are meaningful models for coronectomy. However, for consistent experimental results, coronectomy without flap elevation on the maxillary first molar is recommended.