Objective: To compare coronary artery dimension-adjusted subtended myocardial mass between patients with hypertrophic cardiomyopathy (HCM) and a normal population without detectable atherosclerosis, and between HCM patients with and without chest pain. Materials and Methods: Twenty-five patients with HCM but no detectable atherosclerosis on coronary computed tomography angiography (CCTA) were included in the study. This group comprised 14 patients with chest pain and 11 patients without chest pain. They were matched with 25 healthy participants based on sex, age, coronary dominance pattern, and body surface area. The minimal lumen area (MLA) and subtended myocardial volume (V sub) were assessed in the left main (LM), proximal left anterior descending (pLAD), proximal left circumflex (pLCx), and proximal right coronary (pRCA) arteries. Additionally, an index of the subtended myocardial mass adjusted for the MLA, calculated as V sub/MLA 2 , was determined. Results: MLA was significantly larger in patients with HCM compared to the control group in LM (20.93 ± 6.31 mm 2 vs.15.24 ± 3.90 mm 2 , P< 0.001), pLAD (14.28 ± 3.55 mm 2 vs. 11.36 ± 2.07 mm 2, P = 0.001), pLCx (10.94 ± 3.60 mm 2 vs. 9.15 ± 2.93 mm 2 , P = 0.045), and pRCA (13.41 ± 4.85 mm 2 vs. 11.22 ± 3.20 mm 2 , P = 0.018). Despite an increase in coronary luminal area, patients with HCM exhibited significantly higher V sub/MLA 2 compared to the control group in both the pLAD (403.56 ± 200.35 mm -1 vs. 241.70 ± 85.87 mm -1 , P < 0.001) and the pRCA (186.06 ± 95.07 mm -1 vs. 125.07 ± 70.18 mm -1 , P= 0.007). V sub/MLA 2 was significantly elevated in patients with chest pain compared to those without in the pLAD (473.75 ± 227.38 mm -1 vs. 314.24 ± 110.74 mm -1 , P = 0.018) and the pLCx (417.04 ± 182.65 mm -1 vs. 275.29 ± 112.97 mm -1 , P = 0.044). Conclusion CCTA-derived V sub/MLA 2 may more accurately reflect the balance between myocardial blood supply and demand, offering insights into the occurrence of demand angina in patients with HCM without obstructive coronary artery disease.

Breast magnetic resonance imaging (MRI) is the most sensitive method available for detecting breast cancer, and its use in clinical practice is on the rise. Preoperative breast MRI plays a vital role in assessing the full extent of disease and identifying additional lesions in the contralateral breast that conventional imaging may overlook. These unexpected findings can lead to significant changes in treatment approaches and may ultimately affect long-term outcomes for patients. Despite this, the value of preoperative breast MRI for early-stage breast cancer patients remains a contentious issue. This review evaluates the existing literature on the influence of preoperative breast MRI on clinical outcomes in this patient population.

Background: This study explores effective fixation methods for Pauwel type III femoral neck fractures by evaluating the biomechanical benefits of adding a screw to the Femoral Neck System (FNS). Methods: Computed tomography (CT) scans of an 82-year-old female patient with an intertrochanteric fracture were used to establish a finite element femur model with heterogeneous material properties. Finite element models of Pauwel type III fractures were created with and without an additional screw. The central and inferior trajectories of the FNS bolt were examined separately and combined with an additional screw for virtual fixation. Walking and stair-climbing loads were applied. Results: With the addition of a screw, both peak maximum and minimum principal strains consistently stayed comparable or decreased in models with both central and inferior bolt trajectories, while the volume of elements with principal strain exceeding 1% decreased by more than half. The peak von Mises stress observed in the implants ranged from 215.7 to 359.3 MPa, remaining below the titanium alloy's yield strength of 800 MPa. For normal walking, the addition of a screw to the central bolt trajectory model decreased the fracture gap by 50.6% and reduced sliding distance by 8.6%. For the inferior bolt trajectory, the gap was reduced by 57.9% and sliding distance by 25.0%.Under stair-climbing conditions, these improvements were also evident; the central trajectory model saw a halved fracture gap and a 7.9% decrease in sliding distance, while the inferior trajectory model experienced a 55.7% gap reduction and a 27.2% decrease in sliding distance. The additional screw increased the area ratio of the fracture site experiencing interfragmentary compression 34%–39%, while the additional screw alleviated peak interfragmentary compression by 12%–18% under both normal walking and stair-climbing conditions. Conclusions The addition of a screw reduced the fracture gap, sliding distance, and peak interfragmentary compression, while increasing the area ratio of interfragmentary compression under both walking and stair-climbing loads, regardless of the FNS bolt trajectory, suggesting a better mechanical environment for fracture healing.

Background: The removal of a well-fixed acetabular cup is a challenging, labor-intensive, and time-consuming step during revision hip arthroplasty. Although the advent of the manual osteotome, Explant, has simplified the procedure, it is still a stressful process as it dissipates the surgeon’s strength and time and risks an iatrogenic pelvic fracture. Recently, EZX, a powered tool for extraction of well-fixed acetabular cups with semicircular blade was invented. This study aimed to compare Explant and EZX in an experimental condition for their efficacy and safety. Methods: Cementless acetabular cups were press-fitted to 20 hemipelvic polyurethane models using foam adhesives. Ten cups were removed with each tool for comparison of the elapsed time, loads on the entire hemipelvis, periacetabular strain and temperature, volume of periacetabular bone removed, and diameter of the remaining acetabular rim. Strains and loads were quantitatively assessed using strain gauges and load cells for precise and reliable measurements. Results: The mean duration required to remove a well-fixed cup with EZX was 38.5 seconds (range, 25–55), whereas that with Explant was 543.7 seconds (range, 214–1,051) (p < 0.001). The load on the entire hemipelvis with EZX (mean, 9.1 kgf; range, 6.4–11.3) was 33% lower than that with Explant (mean, 13.6 kgf; range, 9.2–17.1) (p < 0.001). The periacetabular peak strains at the 3 positions with EZX were significantly lower than those with Explant (p < 0.001). The temperature during the removal did not differ significantly between the 2 tools. Although the mean volume of bone loss with Explant was 2.4 mL more than that with EZX (p < 0.001), the mean diameters of the remaining acetabular rim were not significantly different, measuring 54.1 mm with both tools. Conclusions The present experiment revealed that a well-fixed cup could be removed using a powered tool with less strength and time and less load on the entire pelvis. Although the powered tool removed a larger volume of bone, the diameters of the remaining acetabular rims were equivalent. This tool may help surgeons remove well-fixed cups in a short time and reduce the deforming load on the bone around the cup without increasing the size of the subsequent reconstruction cup.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Purpose: Stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT) are increasingly used as initial therapies for brain metastases (BM). We aimed to assess the outcomes of SRS/FSRT in patients aged ≥ 65 years who had 1-10 BM from non–small cell lung cancer (NSCLC). Materials and Methods: We retrospectively reviewed 91 elderly NSCLC patients with 222 BM who were treated with SRS/FSRT at two institutions between 2010 and 2020. The primary endpoint was overall survival (OS) after SRS/FSRT. In addition, in-field local control (IFLC) within the treated field was evaluated. Statistical analysis was performed to identify the prognostic factors affecting OS and IFLC. Results: During a median follow-up of 18 months, the median OS was 32 months. The 1- and 2-year survival rates were 69.8% and 56.1%, respectively. In multivariate analysis, the NSCLC-specific graded prognostic assessment (GPA) score (p=0.007) and administration of systemic therapy (p=0.039) were defined as prognosticators affecting OS. The median IFLC period was 31 months, and the 1- and 2-year IFLC rates were 75.9% and 57.6%, respectively. The total BM volume (p=0.042) significantly affected IFLC. No severe adverse events were reported after SRS/FSRT. Conclusion SRS/FSRT is an effective upfront treatment option for BM arising from NSCLC in elderly patients, with a good OS without severe side effects. Higher GPA score and active systemic treatment were associated with improved OS, indicating that elderly patients are significant candidates for SRS/FSRT.

Objectives: . Salivary gland tumors present a diagnostic challenge, with preoperative false-negative results frequently leading to an unexpected diagnosis of malignancy after parotidectomy. This study was conducted to explore the clinical utility of preoperative core needle biopsy (CNB) in diagnosing malignancies before primary parotidectomy and to assess the prognostic implications of CNB for parotid gland cancers. Methods: . This retrospective cohort study included 615 patients who underwent preoperative CNB and parotidectomy for primary parotid tumors from 2003 to 2023 at a tertiary referral hospital. Among these patients, 102 who were diagnosed with primary parotid malignancy following parotidectomy were examined regarding survival outcomes. Disease-free survival (DFS) and predictive factors were assessed through univariable and multivariable analyses. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of CNB were determined. These metrics were then compared to those of a separate cohort of 547 patients who underwent ultrasound-guided fine needle aspiration (FNA) and parotidectomy within the same timeframe. Results: . In the CNB group, the 5-year predicted DFS was 86.9% (95% CI, 79.2%–95.3%). Multivariable analysis identified male sex (hazard ratio [HR], 8.48; 95% CI, 1.05–68.76) and a CNB finding of malignancy (HR, 8.20; 95% CI, 1.01–66.15) as factors significantly associated with decreased DFS. CNB demonstrated significantly higher sensitivity (89.0%; 95% CI, 81.2%–94.4%) and NPV (97.6%; 95% CI, 95.7%–98.8%) compared to FNA, which had a sensitivity of 45.2% (95% CI, 33.5%–57.3%) and an NPV of 90.8% (95% CI, 87.7%–93.3%). Conclusion . Preoperative CNB may be predictive of parotid cancer prognosis. Patients receiving a diagnosis of malignancy on preoperative CNB demonstrated a worse prognosis compared to those with a “less-than-malignant” diagnosis. Additionally, CNB exhibited higher sensitivity than FNA in identifying malignancies of the parotid gland.

Objective: To compare coronary artery dimension-adjusted subtended myocardial mass between patients with hypertrophic cardiomyopathy (HCM) and a normal population without detectable atherosclerosis, and between HCM patients with and without chest pain. Materials and Methods: Twenty-five patients with HCM but no detectable atherosclerosis on coronary computed tomography angiography (CCTA) were included in the study. This group comprised 14 patients with chest pain and 11 patients without chest pain. They were matched with 25 healthy participants based on sex, age, coronary dominance pattern, and body surface area. The minimal lumen area (MLA) and subtended myocardial volume (V sub) were assessed in the left main (LM), proximal left anterior descending (pLAD), proximal left circumflex (pLCx), and proximal right coronary (pRCA) arteries. Additionally, an index of the subtended myocardial mass adjusted for the MLA, calculated as V sub/MLA 2 , was determined. Results: MLA was significantly larger in patients with HCM compared to the control group in LM (20.93 ± 6.31 mm 2 vs.15.24 ± 3.90 mm 2 , P< 0.001), pLAD (14.28 ± 3.55 mm 2 vs. 11.36 ± 2.07 mm 2, P = 0.001), pLCx (10.94 ± 3.60 mm 2 vs. 9.15 ± 2.93 mm 2 , P = 0.045), and pRCA (13.41 ± 4.85 mm 2 vs. 11.22 ± 3.20 mm 2 , P = 0.018). Despite an increase in coronary luminal area, patients with HCM exhibited significantly higher V sub/MLA 2 compared to the control group in both the pLAD (403.56 ± 200.35 mm -1 vs. 241.70 ± 85.87 mm -1 , P < 0.001) and the pRCA (186.06 ± 95.07 mm -1 vs. 125.07 ± 70.18 mm -1 , P= 0.007). V sub/MLA 2 was significantly elevated in patients with chest pain compared to those without in the pLAD (473.75 ± 227.38 mm -1 vs. 314.24 ± 110.74 mm -1 , P = 0.018) and the pLCx (417.04 ± 182.65 mm -1 vs. 275.29 ± 112.97 mm -1 , P = 0.044). Conclusion CCTA-derived V sub/MLA 2 may more accurately reflect the balance between myocardial blood supply and demand, offering insights into the occurrence of demand angina in patients with HCM without obstructive coronary artery disease.

Objective: To compare coronary artery dimension-adjusted subtended myocardial mass between patients with hypertrophic cardiomyopathy (HCM) and a normal population without detectable atherosclerosis, and between HCM patients with and without chest pain. Materials and Methods: Twenty-five patients with HCM but no detectable atherosclerosis on coronary computed tomography angiography (CCTA) were included in the study. This group comprised 14 patients with chest pain and 11 patients without chest pain. They were matched with 25 healthy participants based on sex, age, coronary dominance pattern, and body surface area. The minimal lumen area (MLA) and subtended myocardial volume (V sub) were assessed in the left main (LM), proximal left anterior descending (pLAD), proximal left circumflex (pLCx), and proximal right coronary (pRCA) arteries. Additionally, an index of the subtended myocardial mass adjusted for the MLA, calculated as V sub/MLA 2 , was determined. Results: MLA was significantly larger in patients with HCM compared to the control group in LM (20.93 ± 6.31 mm 2 vs.15.24 ± 3.90 mm 2 , P< 0.001), pLAD (14.28 ± 3.55 mm 2 vs. 11.36 ± 2.07 mm 2, P = 0.001), pLCx (10.94 ± 3.60 mm 2 vs. 9.15 ± 2.93 mm 2 , P = 0.045), and pRCA (13.41 ± 4.85 mm 2 vs. 11.22 ± 3.20 mm 2 , P = 0.018). Despite an increase in coronary luminal area, patients with HCM exhibited significantly higher V sub/MLA 2 compared to the control group in both the pLAD (403.56 ± 200.35 mm -1 vs. 241.70 ± 85.87 mm -1 , P < 0.001) and the pRCA (186.06 ± 95.07 mm -1 vs. 125.07 ± 70.18 mm -1 , P= 0.007). V sub/MLA 2 was significantly elevated in patients with chest pain compared to those without in the pLAD (473.75 ± 227.38 mm -1 vs. 314.24 ± 110.74 mm -1 , P = 0.018) and the pLCx (417.04 ± 182.65 mm -1 vs. 275.29 ± 112.97 mm -1 , P = 0.044). Conclusion CCTA-derived V sub/MLA 2 may more accurately reflect the balance between myocardial blood supply and demand, offering insights into the occurrence of demand angina in patients with HCM without obstructive coronary artery disease.