Masseter are commonly botulinum neurotoxin targeted muscle for facial contouring in aesthetic field. However, paradoxical masseteric bulging is common adverse effect that has not been discussed with ultrasonographic observations.Retrospective study has been conducted from October, 2021 to January, 2023, out of 324 patients have done blinded botulinum neurotoxin injection in the masseter at the middle and lower portion of the masseter with each side of 25 units (letibotulinum neurotoxin type A), 3 patients demonstrated paradoxical masseteric bulging has been reported and the image observed by ultrasonography by physician. Based on the observations made, we can infer that the function of the moving muscle involves twisting of the muscle fibers during contraction, along with the twisting of the deep inferior tendon, which causes the muscle to be divided into anterior and posterior compartments rather than into superficial and deep compartments of masseter. In ultrasonographic observe the skin surface of a patient with paradoxical masseteric bulging, it is observable that either the anterior or posterior part contracts significantly. The functional units of anterior and posterior compartment are observable as muscular contraction of inward movement of the muscle from either the anterior or posterior functional unit.

Purpose: We investigated the current practices and perceptions of colorectal surgeons in South Korea regarding intracorporeal ileocolic anastomosis (IIA) in minimally invasive right hemicolectomy (RHC). Methods: Members of the Korean Society of Coloproctology (KSCP) participated in an online survey encompassing demographic information, surgical experiences, methods for IIA, and advantages, barriers, and perceptions of IIA. We performed a statistical analysis of survey results. Results: Among the 1,074 KSCP members contacted, 178 responded to the survey. Most respondents were males aged 40–49 years with >10 years of experience who were affiliated with a tertiary healthcare facility. One hundred fifty-six respondents had performed <100 colorectal cancer surgeries annually. Fifty-nine respondents reported experiences of the IIA technique in minimally invasive RHC. Most respondents favored the isoperistaltic side-to-side (S-S) anastomosis and stapled S-S anastomosis, hand-sewn closure for the common channel, and the periumbilical area for primary specimen extraction. Respondents with IIA experience emphasized the reduction in postoperative complications as the primary reason for performing IIA, whereas respondents without IIA experience cited the lack of benefits as the main deterrent. Respondents commonly cited concerns regarding anastomotic leakage and intraabdominal contamination as the primary reasons for not performing IIA. Respondents with IIA experience demonstrated a more positive response towards attempting or transitioning to IIA than those without. Respondents with IIA experience prioritized self-sufficiency, whereas respondents without IIA experience prioritized proctorship and discussions of the initial cases. Conclusion Measures to standardize the IIA technique and appropriate training programs must be implemented to enhance its use in minimally invasive RHC.

Purpose: Intracorporeal anastomosis (IA) in laparoscopic right hemicolectomy has been associated with faster recovery in bowel function compared to extracorporeal anastomosis (EA). However, the technical difficulty of laparoscopic suturing technique and intraabdominal fecal contamination hinder many surgeons from implementing such a procedure. We introduce and compare a bridging technique designated as “semi-extracorporeal” anastomosis (SEA), which embraces the advantages and amends the drawbacks of IA and EA. Methods: Between May 2016 and October 2022, 100 patients who underwent laparoscopic right hemicolectomy were analyzed. All patients who received laparoscopic right hemicolectomy underwent one of the 3 anastomosis methods (EA, SEA, and IA) by a single colorectal surgeon at a single tertiary care hospital. Data including perioperative parameters and postoperative outcomes were analyzed by each group. Results: A total of 100 patients were reviewed. Thirty patients underwent EA; 50 and 20 patients underwent SEA and IA, respectively. Operation time (minute) was 170 (range, 100–285), 170 (range, 110–280), and 147.5 (range, 80–235) in EA, SEA, and IA, respectively (P = 0.010). Wound size was smaller in SEA and IA compared to EA (P < 0.001). IA was associated with a shorter time (day) to first flatus compared to SEA and EA (4 [range, 2–13] vs. 4 [range, 2–7] vs. 2.5 [range, 1–4], P < 0.001).Postoperative complication showed no statistical significance between the 3 groups. Conclusion Semi-extracorporeal was an attractive bridging option for colorectal surgeons worrisome of the technical difficulty of IA while maintaining faster bowel recovery and smaller wound incisions compared to EA.

Purpose: Risk factors predicting distant metastasis (DM) in extrahepatic bile duct cancer (EHBDC) patients treated with curative resection were investigated. Materials and Methods: Medical records of 1,418 EHBDC patients undergoing curative resection between Jan 2000 and Dec 2015 from 14 institutions were reviewed. After resection, 924 patients (67.6%) were surveilled without adjuvant therapy, 297 (21.7%) were treated with concurrent chemoradiotherapy (CCRT) and 148 (10.8%) with CCRT followed by chemotherapy. To exclude the treatment effect from innate confounders, patients not treated with adjuvant therapy were evaluated. Results: After a median follow-up of 36.7 months (range, 2.7 to 213.2 months), the 5-year distant metastasis-free survival (DMFS) rate was 57.7%. On multivariate analysis, perihilar or diffuse tumor (hazard ratio [HR], 1.391; p=0.004), poorly differentiated histology (HR, 2.014; p < 0.001), presence of perineural invasion (HR, 1.768; p < 0.001), positive nodal metastasis (HR, 2.670; p < 0.001) and preoperative carbohydrate antigen (CA) 19-9 ≥ 37 U/mL (HR, 1.353; p < 0.001) were significantly associated with inferior DMFS. The DMFS rates significantly differed according to the number of these risk factors. For validation, patients who underwent adjuvant therapy were evaluated. In patients with ≥ 3 factors, additional chemotherapy after CCRT resulted in a superior DMFS compared with CCRT alone (5-year rate, 47.6% vs. 27.7%; p=0.001), but the benefit of additional chemotherapy was not observed in patients with 0-2 risk factors. Conclusion Tumor location, histologic differentiation, perineural invasion, lymph node metastasis, and preoperative CA 19-9 level predicted DM risk in resected EHBDC. These risk factors might help identifying a subset of patients who could benefit from additional chemotherapy after resection.

Thyroid surgery complications include voice change, vocal fold paralysis, and hypoparathyroidism. The voice status should be evaluated pre- and post-surgery. In patients with voice change, laryngeal visualization is needed.Intraoperative neuromonitoring helps reduce recurrent laryngeal nerve injury. The measurement of serum calcium, parathyroid hormone, and 25-hydroxyvitamin D levels is recommended to evaluate perioperative parathyroid function and prescribe supplementation preoperatively if necessary. For postoperative hypoparathyroidism, vitamin D and oral calcium supplementation are indicated based on serum parathyroid hormone and calcium levels and the severity of symptoms or signs of hypocalcemia. If long-term treatment is required, the appropriateness of treatment should be evaluated based on the disease itself and the consideration of potential benefits and harms from long-term replacement.

Differentiated thyroid cancer demonstrates a wide range of clinical presentations, from very indolent cases to those with an aggressive prognosis. Therefore, diagnosing and treating each cancer appropriately based on its risk status is important. The Korean Thyroid Association (KTA) has provided and amended the clinical guidelines for thyroid cancer management since 2007. The main changes in this revised 2024 guideline include 1) individualization of surgical extent according to pathological tests and clinical findings, 2) application of active surveillance in low-risk papillary thyroid microcarcinoma, 3) indications for minimally invasive surgery, 4) adoption of World Health Organization pathological diagnostic criteria and definition of terminology in Korean, 5) update on literature evidence of recurrence risk for initial risk stratification, 6) addition of the role of molecular testing, 7) addition of definition of initial risk stratification and targeting thyroid stimulating hormone (TSH) concentrations according to ongoing risk stratification (ORS), 8) addition of treatment of perioperative hypoparathyroidism, 9) update on systemic chemotherapy, and 10) addition of treatment for pediatric patients with thyroid cancer.

Background: and Purpose Early- and late-onset Alzheimer’s disease (EOAD and LOAD, respectively) share the same neuropathological hallmarks of amyloid and neurofibrillary tangles but have distinct cognitive features. We compared structural brain connectivity between the EOAD and LOAD groups using structural network efficiency and evaluated the association of structural network efficiency with the cognitive profile and pathological markers of Alzheimer’s disease (AD). Methods: The structural brain connectivity networks of 80 AD patients (47 with EOAD and 33 with LOAD) and 57 healthy controls were reconstructed using diffusion-tensor imaging.Graph-theoretic indices were calculated and intergroup differences were evaluated. Correlations between network parameters and neuropsychological test results were analyzed. The correlations of the amyloid and tau burdens with network parameters were evaluated for the patients and controls. Results: Compared with the age-matched control group, the EOAD patients had increased global path length and decreased global efficiency, averaged local efficiency, and averaged clustering coefficient. In contrast, no significant differences were found in the LOAD patients. Locally, the EOAD patients showed decreases in local efficiency and the clustering coefficient over a wide area compared with the control group, whereas LOAD patients showed such decreases only within a limited area. Changes in network parameters were significantly correlated with multiple cognitive domains in EOAD patients, but only with Clinical Dementia Rating Sum-of-Boxes scores in LOAD patients. Finally, the tau burden was correlated with changes in network parameters in AD signature areas in both patient groups, while there was no correlation with the amyloid burden. Conclusions The impairment of structural network efficiency and its effects on cognition may differ between EOAD and LOAD.

Purpose: Alzheimer’s disease (AD) dementia may not be a single disease entity. Early-onset AD (EOAD) and late-onset AD (LOAD) have been united under the same eponym of AD until now, but disentangling the heterogeneity according to the age of sonset has been a major tenet in the field of AD research. Materials and Methods: Ninety-nine patients with AD (EOAD, n=54; LOAD, n=45) and 66 cognitively normal controls completed both [18F]THK5351 and [18F]flutemetamol (FLUTE) positron emission tomography scans along with structural magnetic resonance imaging and detailed neuropsychological tests. Results: EOAD patients had higher THK retention in the precuneus, parietal, and frontal lobe, while LOAD patients had higher THK retention in the medial temporal lobe. Intravoxel correlation analyses revealed that EOAD presented narrower territory of local FLUTE-THK correlation, while LOAD presented broader territory of correlation extending to overall parieto-occipito-temporal regions. EOAD patients had broader brain areas which showed significant negative correlations between cortical thickness and THK retention, whereas in LOAD, only limited brain areas showed significant correlation with THK retention. In EOAD, most of the cognitive test results were correlated with THK retention. However, a few cognitive test results were correlated with THK retention in LOAD. Conclusion LOAD seemed to show gradual increase in tau and amyloid, and those two pathologies have association to each other. On the other hand, in EOAD, tau and amyloid may develop more abruptly and independently. These findings suggest LOAD and EOAD may have different courses of pathomechanism.

Background: Botulinum toxin type A (BTX-A) injection is being widely used off-label for muscular hypertrophy, including deltoid muscle hypertrophy. However, very few studies have evaluated the optimal dosage and its clinical response. Objective: This study aimed to assess the efficacy and safety of different doses of Prabotulinum toxin A (PBoNT) for treating deltoid muscle hypertrophy. Methods: Twelve particiapants with bilateral deltoid muscle hypertrophy were enrolled and randomly received either 16 U or 32 U of PBoNT. In each participant, the same dose was administered to both deltoid muscles. Both participants and evaluators were blinded. Deltoid muscle thickness and upper arm circumference were measured on day 0, and weeks 2, 4, and 12 after the PBoNT injection. Results: Upper arm circumference significantly decreased in both groups; however, deltoid muscle thickness was reduced in the 16 U group only. No major complications were reported in both groups. However, a few minor complications were reported in the 16 U injection group. Conclusion Both 16 U and 32 U of PBoNT intramuscular injections are safe and effective in treating deltoid hypertrophy.

Purpose: This study investigated the orthodontic tooth movement after weekly parathyroid hormone (PTH) injection in mongrel dogs and analyzes bone formation activity on the tension and pressure sides of the tooth movement in mongrel dogs. Materials and Methods: Three mongrel dogs were used in this study. The first premolar was extracted and orthodontic force using 150 g of closed coil springs between the canine and second premolar was applied. The low-dose PTH group (PTH_1) and high-dose PTH group (PTH_2) received weekly injections of 1.61 μg/kg and 3.23 μg/kg of PTH, respectively. The control group received weekly injections of 1 ml of saline. Clinical, histomorphometric analysis were carried out.Result: The orthodontic tooth movement was greatest in the PTH_2 group and the lowest in the control group. Fluorescence staining images showed higher bone remodeling on the tension side of the tooth movement in the PTH_1 and PTH_2 groups. PTH_2 group showed a thicker labeling band than the PTH_1 group. PTH_2 group showed the highest mineral apposition rate and bone formation rate, followed by the PTH_1 group and the control group. Conclusion Weekly intermittent PTH injection, especially in the short-term and at higher doses with orthodontic force, successfully increased orthodontic tooth movement and bone remodeling in mongrel dogs.