Combining transcatheter arterial embolization with endoscopic debulking for hypervascular airway tumor management: a retrospective single center study.

Background: Airway obstruction due to tumor invasion or concurrent respiratory distress and hemoptysis poses a significant challenge in clinical management, often requiring prompt and effective intervention to alleviate symptoms and improve patient outcomes. This study aimed to evaluate the efficacy and safety of selective transcatheter arterial embolization (TAE) as a preparatory measure to mitigate airway obstruction before bronchoscopic debulking as an approach to address this clinical challenge. Methods: The data of patients with airway obstruction due to tumor invasion or concurrent respiratory distress and hemoptysis treated at The First Affiliated Hospital of Zhengzhou University from January 2018 to August 2022 were analyzed. After computed tomography (CT) scans and bronchoscopic findings were assessed, selective TAE was performed as a preparatory measure to alleviate airway obstruction before bronchoscopic debulking, and the occurrence of hemorrhage-related complications, Karnofsky Performance Status (KPS) score, breathlessness index, and the extent of airway obstruction were evaluated. Results: All 22 patients underwent selective TAE before bronchoscopic tumor debulking. The overall efficacy rate was 100%, with a significant improvement in the KPS score from preoperative (60.45±14.63) to postoperative (74.55±9.63) levels (t=-6.891; P<0.001). Similarly, there was a considerable reduction in the shortness of breath score from preoperative (2.91±0.81) to postoperative (1.73±0.63) levels (t=6.973; P<0.001). Airway obstruction decreased substantially from preoperative (79.14%±14.56%) to postoperative (21.27%±7.19%) levels (t=26.857; P<0.001). Furthermore, the severity classification of airway obstruction decreased from preoperative (4±0.82) to postoperative (1.36±0.49) levels (t=18.794; P<0.001). Among the patients, only one experienced moderate bleeding necessitating prolonged mechanical balloon compression and intracavitary lesion removal, while the other patients had minor and negligible bleeding. Conclusions: TAE combined with endoscopic debulking can effectively control intraoperative bleeding and respiratory distress and achieve successful local resolution of endotracheal hypervascular tumors.

Shear wave elastography of transverse carpal ligament increased with simulated carpal tunnel pressure.

BACKGROUND: Elevation of carpal tunnel pressure is known to be associated with carpal tunnel syndrome. This study aimed to correlate the shear wave elastography in the transverse carpal ligament (TCL) with carpal tunnel pressures using a cadaveric model. METHODS: Eight human cadaveric hands were dissected to evacuate the tunnels. A medical balloon was inserted into each tunnel and connected to a pressure regulator to simulate tunnel pressure in the range of 0-210 mmHg with an increment of 30 mmHg. Shear wave velocity and modulus was measure in the middle of TCL. RESULTS: SWV and SWE were significantly dependent on the pressure levels (p < 0.001), and positively correlated to the tunnel pressure (SWV: R = 0.997, p < 0.001; SWE: R = 0.996, p < 0.001). Regression analyses showed linear relationship SWV and pressure (SWV = 4.359 + 0.0263 * Pressure, R2 = 0.994) and between SWE and pressure (SWE = 48.927 + 1.248 * Pressure, R2 = 0.996). CONCLUSION: The study indicated that SWV and SWE in the TCL increased linearly as the tunnel pressure increased within the current pressure range. The findings suggested that SWV/SWE in the TCL has the potential for prediction of tunnel pressure and diagnosis of carpal tunnel syndrome.

Graphene oxide-loaded rapamycin coating on airway stents inhibits stent-related granulation tissue hyperplasia.

OBJECTIVES: Our objective was to explore the safety and efficacy of a graphene oxide-loaded rapamycin-coated self-expandable metallic airway stent (GO@RAPA-SEMS) in a rabbit model. METHODS: The dip coating method was used to develop a GO@RAPA-SEMS and a poly(lactic-co-glycolic)-acid loaded rapamycin-coated self-expandable metallic airway stent (PLGA@RAPA-SEMS). The surface structure was evaluated using a scanning electronic microscope. The in vitro drug-release profiles of the 2 stents were explored and compared. In the animal study, a total of 45 rabbits were randomly divided into 3 groups and underwent 3 kinds of stent placements. Computed tomography was performed to evaluate the degree of stenosis at 1, 2 and 3 months after the stent operation. Five rabbits in each group were sacrificed after the computed tomography scan. The stented trachea and blood were collected for further pathological analysis and laboratory testing. RESULTS: The in vitro drug-release study revealed that GO@RAPA-SEMS exhibited a sudden release on the first day and maintained a certain release rate on the 14th day. The PLGA@RAPA-SEMS exhibited a longer sustained release time. All 45 rabbits underwent successful stent placement. Pathological results indicated that the granulation tissue thickness in the GO@RAPA-SEMS group was less than that in the PLGA@RAPA-SEMS group. The TUNEL and hypoxia-inducible factor-1α staining results support the fact that the granulation inhibition effect in the GO@RAPA-SEMS group was greater than that in the PLGA@RAPA-SEMS group. CONCLUSIONS: GO@RAPA-SEMS effectively inhibited stent-related granulation tissue hyperplasia.

Estimation of radiographic joint space of the trapeziometacarpal joint with computed tomographic validation.

Purpose: Joint space width (JSW) is a common metric used to evaluate joint structure on plain radiographs. For the hand, quantitative techniques are available for evaluation of the JSW of finger joints; however, such techniques have been difficult to establish for the trapeziometacarpal (TMC) joint. This study aimed to develop a validated method for measuring the radiographic joint space of the healthy TMC joint. Approach: Computed tomographic scans were taken of 15 cadaveric hands. The location of a JSW analysis region on the articular surface of the first metacarpal was established in 3D space and standardized in a 2D projection. The standardized region was applied to simulated radiographic images. A correction factor was defined as the ratio of the CT-based and radiograph-based joint space measurements. Leave-one-out validation was used to correct the radiograph-based measurements. A t-test was used to evaluate the difference between CT-based and corrected radiograph-based measurements (α=0.05). Results: The CT-based and radiograph-based measurements of JSW were 3.61±0.72 mm and 2.18±0.40 mm, respectively. The correction factor for radiograph-based joint space was 1.69±0.41. Before correction, the difference between the CT-based and radiograph-based joint space was 1.43 mm [95% CI: 0.99-1.86 mm; p<0.001]. After correction, the difference was -0.11 mm [95% CI: -0.63-0.41 mm; p=0.669]. Conclusions: Corrected measurements of radiographic TMC JSW agreed well with CT-measured JSW. With in-vivo validation, the developed methodology has potential for automated and accurate radiographic measurement of TMC JSW.

Paclitaxel-coated balloon catheter for benign esophageal stenosis in a rabbit model.

Most patients with benign esophageal stenosis require multiple or even continuous balloon dilation treatments to achieve symptom relief. In this study, eighteen rabbits were used to establish an esophageal benign stenosis model and were divided into a control group (n = 6), a balloon group (n = 6) and a PTX-coated balloon group (n = 6) to evaluate the feasibility and effectiveness of paclitaxel (PTX)-coated balloons for the rabbit esophageal benign stenosis model. The weight and esophageal diameter were recorded every 2 weeks until 8 weeks post-surgery. Hematoxylin-eosin staining, Masson's trichrome staining and immunohistochemical staining were performed for pathological analysis. Four weeks post-operation, there was a significant difference in weight between the control group and the balloon group (p = 0.01) and between the control group and the PTX balloon group (p = 0.01). There was a significant difference in the esophageal diameter between the balloon group and the PTX balloon group at 8 weeks post-operation (p = 0.02). Four weeks post-operation, the degree of inflammatory cell infiltration in the PTX balloon group was significantly lower than that in the control group (p = 0.002) and balloon group (p = 0.001). The degree of collagen deposition in the PTX balloon group was significantly lower than that in the control group (p = 0.002) and balloon group (p = 0.03). Eight weeks post-operation, the percentage of cells positive for TGF-ß (p < 0.001), the degree of inflammatory cell infiltration (p = 0.02) and the degree of collagen deposition (p = 0.02) in the PTX balloon group were significantly lower than those in the balloon group. Therefore, PTX-coated balloons may alleviate the local inflammatory response and collagen deposition when used during dilation treatment of benign esophageal stenosis.

Celecoxib and cisplatin dual-loaded microspheres synergistically enhance transarterial chemoembolization effect of hepatocellular carcinoma.

Transarterial chemoembolization (TACE) is a first-line treatment for intermediate to advanced-stage liver cancer, with drug-eluting microspheres commonly used as embolic agents. However, currently available drug-eluting microspheres suffer from low drug-loading capacity and limited drug options. In this work, we developed polydopamine-modified polyvinyl alcohol dual-drug-loaded microspheres encapsulating celecoxib and cisplatin (referred to as PCDMS). Physicochemical characterization revealed that the surface of the microspheres displayed increased roughness after polydopamine modification, and celecoxib and cisplatin were successfully loaded onto the microsphere surface. In vitro cell experiments demonstrated that the PCDMS significantly inhibited the proliferation and migration of highly metastatic human liver cancer cells (MHCC-97H) and human liver cancer cells (SMMC-7721). Furthermore, the dual-loaded microspheres exhibited remarkable tumor growth inhibition and reshaped the tumor microenvironment in both subcutaneous H22 liver cancer model in Balb/c mice and intrahepatic VX2 tumor model in New Zealand rabbits, demonstrating a synergistic antitumor effect where 1 + 1>2. This work provides a potential therapeutic approach for the treatment of refractory liver cancer and holds significant translational potential.

Application of temperature-sensitive liquid embolic agent loaded with oxaliplatin in the TACE procedure for rabbit VX2 gastric cancer.

As a promising drug delivery system, the temperature-sensitive liquid embolic agent (TempSLE) has yet to be reported in animal experiments in treating gastric cancer. We observed and compared computed tomography (CT) imaging changes, tumor volume, HE staining, and immunohistochemistry after transcatheter arterial chemoembolization (TACE) treatment in rabbit VX2 gastric cancer models to clarify the effectiveness of TempSLE loaded with oxaliplatin (TempSLE/Oxa) in treating gastric cancer. One milliliter TempSLE can be loaded with 20 mg oxaliplatin. The accumulative drug release rate at 30 min was 38.76%, and after 24 h, it reached more than 90%. CT examination 1 week after TACE revealed that the TempSLE/Oxa group presents unenhanced hypodense necrotic foci, the iodinated oil loaded with oxaliplatin (Ioil/Oxa) group presents shrinking tumors but still visible speckled foci of enhancement, and the normal saline (NS) group presents heterogeneous enhancement with larger tumors than before. In the postoperative autopsy of TACE, the tumor volumes of TempSLE/Oxa, Ioil/Oxa, and NS groups were 0.15 ± 0.06 cm3, 0.37 ± 0.11 cm3, and 1.19 ± 0.16 cm3, respectively, all of which were statistically different. The positive vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) expression percentages in the TempSLE/Oxa, Ioil/Oxa, and NS groups were statistically different and lowest in the TempSLE/Oxa group. In conclusion, the TempSLE can load a high dose of oxaliplatin to meet the demand of clinical applications. TempSLE/Oxa could effectively inhibit tumor cell proliferation and angiogenesis. This study provides experimental evidence for the further clinical application of the TempSLE/Oxa.

Transcatheter arterial chemoembolization combined with apatinib and camrelizumab for unresectable advanced gastric or gastroesophageal junction cancer: a single-arm, single-center, retrospective study.

Purpose: This study aims to investigate the efficacy and safety of transcatheter arterial chemoembolization (TACE) combined with Apatinib and Camrelizumab for treating unresectable advanced gastric or gastroesophageal junction (G/GEJ) cancer. Material and methods: In this study, data of patients with unresectable advanced G/GEJ cancer who received TACE combined with Apatinib and Camrelizumab from August 2018 to December 2021 was evaluated. After TACE, patients were given intravenous Camrelizumab 200mg every three weeks and oral apatinib 250mg/day for treatment. The primary endpoint was overall survival (OS), and the secondary endpoints were objective response rate (ORR), disease control rate (DCR), and adverse events (AEs). Results: A total of 49 patients were enrolled in this study. The median follow-up time was 14.0 months, and the median OS was 20.0 months (95% CI = 13.6-26.4). Two patients (4.08%) achieved complete remission, 28 patients (57.14%) achieved partial remission, 18 patients (36.73%) had stable disease, and 1 patient (2.04%) had disease progression. The ORR was 61.22%, and the DCR was 97.96%. Multivariate Cox regression analysis indicated that age (HR 4.74, 95% CI = 1.674-13.440, P=0.003) and multiple distant metastases (HR 20.916, 95% CI = 4.094-106.808, P = 0.001) were independent risk factors for OS. Most AEs were classified as grade 1-2, the most common being RCCEP (69.39%). There were 5 cases of grade 3-4 adverse events (10.20%). No patients discontinued or reduced the treatment dose due to AEs, and all patients received symptomatic treatment. Conclusion: TACE combined with Apatinib and Camrelizumab is a safe and effective therapeutic option for patients with unresectable advanced G/GEJ cancer, which can significantly improve the median OS and ORR of patients. And the adverse events (AEs) are tolerable and manageable.

Bevacizumab-loaded CalliSpheres beads: in vitro loading, release profiles and application in rabbit liver VX2 tumor model.

Background: Bevacizumab loaded drug-eluting beads have the potential to reduce TACE related VEGF expression. The purpose of this study was to investigate the in vitro loading, and release profiles of bevacizumab (BEV) loaded on Callispheres beads (CB) and its application in rabbit liver VX2 tumor model. Methods: CB with sizes of 100-300 um and 300-500 um were divided into 5 groups, respectively. BEV with different content was prepared for CB loading, releasing and detected in the solution at different time points. The diameters of CB in each group were measured under a light microscope to calculate the shrinkage rate. The rabbit with VX2 liver model were divided into control group, CB-TACE group, CB-TACE+BEV group, and BEV group. The data of blood test, CT image, HE and IHC staining were compared and analyzed. Results: The shrinkage rate of the 100-300 um CB was 2.6-7.2%, while the 300-500 um CB was 0.2-7.1%. The BEV-loaded CB (BEV-CB) has a burst release during the first hour and following gradually released with time. The release profiles of 100-300 um CB reach 34% in 24 hours, while the 300-500 um CB to 25.8%. BEV-CB with sizes of 100-300 um was chosen to perform transcatheter arterial chemoembolization (TACE). The results showed that BEV-CB-TACE not only gradually increased the content of BEV in serum and organ tissue but also reduced the level of VEGF in serum. Pathological results suggested that the expression of HIF-1 was elevated while VEGF and MVD decreased when compared to the other groups. Conclusion: In conclusion, this study confirms that Callispheres beads could efficiency loaded BEV. BEV-CB-TACE has a good safety and effectiveness, and its application could reduce the level of VEGF-A in serum in the treatment of VX2 tumors.

Covered SEMS failed to cure airway fistula closed by an amplatzer device.

BACKGROUND: Airway fistula is a rare but threatening complication associated with high rates of morbidity and mortality. We report the experience of Amplatzer device application in airway fistulae that failed to be cured with a covered self-expandable metallic stent (SEMS). MATERIALS AND METHODS: Patients who failed occlusion with a covered self-expandable metallic stent and received Amplatzer device placement from Jan 2015 to Jan 2020 were retrospectively enrolled. A total of 14 patients aged 42 to 66 years (55.14 ± 7.87) were enrolled in this study. The primary diseases, types of fistula, types of stents, duration, size of fistula, and follow-up were recorded. RESULTS: All 14 patients with airway fistula failed to be occluded with a covered metallic stent and received Amplatzer device placement. Among the 14 patients, 6 had BPF, 3 had TEF and 5 had GBF. The average stent time was 141.93 ± 65.83 days. The sizes of the fistulae ranged from 3 to 6 mm. After Amplatzer device placement, the KPS score improved from 62.14 ± 4.26 to 75.71 ± 5.13 (P < 0.05). No procedure-related complications occurred. During the 1-month, 3-month and 6-month follow-ups, all the Amplatzer devices were partially surrounded with granulation. Only 1 patient with BPF failed with Amplatzer device occlusion due to the recurrence of lung cancer. CONCLUSION: In conclusion, the application of the Amplatzer device is a safe and effective option in the treatment of airway fistula that failed to be occluded with SEMSs.

Randomized Clinical Trials and Observational Tribulations: Providing Clinical Evidence for Personalized Surgical Pain Management Care Models.

Proving clinical superiority of personalized care models in interventional and surgical pain management is challenging. The apparent difficulties may arise from the inability to standardize complex surgical procedures that often involve multiple steps. Ensuring the surgery is performed the same way every time is nearly impossible. Confounding factors, such as the variability of the patient population and selection bias regarding comorbidities and anatomical variations are also difficult to control for. Small sample sizes in study groups comparing iterations of a surgical protocol may amplify bias. It is essentially impossible to conceal the surgical treatment from the surgeon and the operating team. Restrictive inclusion and exclusion criteria may distort the study population to no longer reflect patients seen in daily practice. Hindsight bias is introduced by the inability to effectively blind patient group allocation, which affects clinical result interpretation, particularly if the outcome is already known to the investigators when the outcome analysis is performed (often a long time after the intervention). Randomization is equally problematic, as many patients want to avoid being randomly assigned to a study group, particularly if they perceive their surgeon to be unsure of which treatment will likely render the best clinical outcome for them. Ethical concerns may also exist if the study involves additional and unnecessary risks. Lastly, surgical trials are costly, especially if the tested interventions are complex and require long-term follow-up to assess their benefit. Traditional clinical testing of personalized surgical pain management treatments may be more challenging because individualized solutions tailored to each patient's pain generator can vary extensively. However, high-grade evidence is needed to prompt a protocol change and break with traditional image-based criteria for treatment. In this article, the authors review issues in surgical trials and offer practical solutions.

Microinjection Molded Biopolymeric Airway Stent with Antibacterial and Anti-Hyperplastic Properties.

Central airway stenosis is a condition that the diameter of the trachea or main bronchus shrinkage is caused by external compression or internal tissue hyperplasia, which can cause difficulty breathing, asphyxia, and even death. Airway stenting is an easy way to restore the patency of the central airway, but airway stents commonly used in clinical practice can lead to complications such as mucus plugging, bacterial infection, and granulation tissue hyperplasia. Moreover, the non-degradable characteristic makes it requires a second operation to remove, which has the potential to cause tissue damage. In this study, a biodegradable airway stent is fabricated by microinjection molding using the bioelastomer of poly (L-lactide-co-ε-caprolactone) as the matrix material. The airway stent has excellent mechanical properties and an appropriate degradation rate. The hydrophilic surface of the airway stent can inhibit mucus plugging. The loading of silver nanoparticles and cisplatin endows the stent with antibacterial and anti-hyperplastic functions. In vitro and in vivo experiments demonstrate that this study provides an antibacterial and anti-hyperplastic biodegradable airway stent with elastic properties to avoid secondary removal operation and reduce complications associated with mucus plugging, bacterial infection, and granulation tissue hyperplasia.

Bevacizumab loaded CalliSpheres® bronchial arterial chemoembolization combined with immunotherapy and targeted therapy for advanced lung adenocarcinoma.

Background: As a new drug delivery and embolization system, drug-eluted bronchial artery chemoembolization (DEB-BACE) can not only embolize the tumor blood supply artery but also load chemotherapy drugs and slowly release them into the local environment. Bevacizumab (BEV) combined with chemotherapy drugs has attained significant achievements in the first-line treatment of advanced non-squamous non-small cell lung cancer (NSCLC). The role of BEV-loaded DEB-BACE combined with immunotherapy and targeted therapy in patients with lung adenocarcinoma (LUAD) is unclear. This study was designed to evaluate the efficacy and safety of bevacizumab-loaded CalliSpheres® bronchial arterial chemoembolization combined with immunotherapy and targeted therapy in patients with lung adenocarcinoma. Methods: Nine patients with LUAD who received BEV-loaded CalliSpheres® BACE combined with immunotherapy and targeted therapy from 1 Jan 2021 to Dec 2021 were included in this study. The primary endpoint was the disease control rate (DCR) and the objective response rate (ORR). The secondary endpoints were the overall survival rates (OS) at 6 months and 12 months. The tumor response was evaluated according to the mRECIST standard. Safety was assessed by the occurrences of adverse events and the severity of the adverse events. Results: All patients received CalliSpheres® BACE loaded with BEV (200 mg) in combination with immunotherapy and targeted therapy. A total of nine patients received the BACE procedures 20 times, four of them received a third session of BACE, three underwent a second session of DEB-BACE, and two underwent one cycle of DEB-BACE. Partial response and stable disease were found in seven (77.8%), and two (22.2%) patients, respectively, 1 month after the last multimodal treatment. The ORR at 1, 3, 6, and 12 months was 77.8%, 66.7%, 44.4%, and 33.3%, respectively, while the DCR was 100%, 77.8%, 44.4%, and 33.3%, respectively. The OS rates at 6-and 12-month were 77.8% and 66.7%, respectively. There were no serious adverse events. Conclusion: BEV-loaded CalliSpheres® transcatheter bronchial arterial chemoembolization combined with immunotherapy and targeted therapy is a promising and well-tolerated treatment for patients with lung adenocarcinoma.

The Changing Environment in Postgraduate Education in Orthopedic Surgery and Neurosurgery and Its Impact on Technology-Driven Targeted Interventional and Surgical Pain Management: Perspectives from Europe, Latin America, Asia, and The United States.

Personalized care models are dominating modern medicine. These models are rooted in teaching future physicians the skill set to keep up with innovation. In orthopedic surgery and neurosurgery, education is increasingly influenced by augmented reality, simulation, navigation, robotics, and in some cases, artificial intelligence. The postpandemic learning environment has also changed, emphasizing online learning and skill- and competency-based teaching models incorporating clinical and bench-top research. Attempts to improve work-life balance and minimize physician burnout have led to work-hour restrictions in postgraduate training programs. These restrictions have made it particularly challenging for orthopedic and neurosurgery residents to acquire the knowledge and skill set to meet the requirements for certification. The fast-paced flow of information and the rapid implementation of innovation require higher efficiencies in the modern postgraduate training environment. However, what is taught typically lags several years behind. Examples include minimally invasive tissue-sparing techniques through tubular small-bladed retractor systems, robotic and navigation, endoscopic, patient-specific implants made possible by advances in imaging technology and 3D printing, and regenerative strategies. Currently, the traditional roles of mentee and mentor are being redefined. The future orthopedic surgeons and neurosurgeons involved in personalized surgical pain management will need to be versed in several disciplines ranging from bioengineering, basic research, computer, social and health sciences, clinical study, trial design, public health policy development, and economic accountability. Solutions to the fast-paced innovation cycle in orthopedic surgery and neurosurgery include adaptive learning skills to seize opportunities for innovation with execution and implementation by facilitating translational research and clinical program development across traditional boundaries between clinical and nonclinical specialties. Preparing the future generation of surgeons to have the aptitude to keep up with the rapid technological advances is challenging for postgraduate residency programs and accreditation agencies. However, implementing clinical protocol change when the entrepreneur-investigator surgeon substantiates it with high-grade clinical evidence is at the heart of personalized surgical pain management.

External beam radiotherapy inhibits stent related granulation hyperplasia in rabbit trachea.

Endobronchial stent exacerbates the formation of granulation tissue. Radiotherapy maybe a durable treatment option for granulation hyperplasia. In this study, we explore the results of external beam radiotherapy (EBRT) for granulation hyperplasia after airway stent placement. A total of 30 New Zealand rabbits were assigned in three groups, Control group (n = 12), low dosage (LD, 12 Gy in 4 fractions and twice a week) group (n = 9) and high dosage (HD, 20 Gy in 4 fractions and twice a week) group (n = 9). Post-stenting 1 week, LD and HD group started to receive EBRT. Bronchoscopy, Haematoxylin-eosin (HE), Masson's trichrome (MTS), Safranin O (SO) and immunohistochemical (IHC) staining protocols were performed to evaluate the histopathological changes of trachea. A total of 30 stents were successfully implanted in 30 rabbits. No procedure-related death and complications happened. Post-stenting 4 w, 8 w and 12 w, the ventilate area ratio (VAR) and qualitative histological scoring (QHS) in the LD group and HD group lower than the Control group. Post-stenting 12w, the immunohistochemical results revealed that the positive percentage of TGF-ß and VEGF in the LD group and HD group were lower than the Control group. In conclusion, the present study investigated the efficacy of EBRT in reducing stent related granulation tissue formation in the rabbit trachea. Higher dosage EBRT with a better result in inhibiting granulation hyperplasia.

Comparison of evaluation metrics of deep learning for imbalanced imaging data in osteoarthritis studies.

PURPOSE: To compare the evaluation metrics for deep learning methods that were developed using imbalanced imaging data in osteoarthritis studies. MATERIALS AND METHODS: This retrospective study utilized 2996 sagittal intermediate-weighted fat-suppressed knee MRIs with MRI Osteoarthritis Knee Score readings from 2467 participants in the Osteoarthritis Initiative study. We obtained probabilities of the presence of bone marrow lesions (BMLs) from MRIs in the testing dataset at the sub-region (15 sub-regions), compartment, and whole-knee levels based on the trained deep learning models. We compared different evaluation metrics (e.g., receiver operating characteristic (ROC) and precision-recall (PR) curves) in the testing dataset with various class ratios (presence of BMLs vs. absence of BMLs) at these three data levels to assess the model's performance. RESULTS: In a subregion with an extremely high imbalance ratio, the model achieved a ROC-AUC of 0.84, a PR-AUC of 0.10, a sensitivity of 0, and a specificity of 1. CONCLUSION: The commonly used ROC curve is not sufficiently informative, especially in the case of imbalanced data. We provide the following practical suggestions based on our data analysis: 1) ROC-AUC is recommended for balanced data, 2) PR-AUC should be used for moderately imbalanced data (i.e., when the proportion of the minor class is above 5% and less than 50%), and 3) for severely imbalanced data (i.e., when the proportion of the minor class is below 5%), it is not practical to apply a deep learning model, even with the application of techniques addressing imbalanced data issues.

Carpal arch space increased by volar force applied to the skin surface above the carpal tunnel.

BACKGROUND: Carpal arch space augmentation can help decompress the median nerve. The augmentation can be achieved by mechanical manipulations utilizing the biomechanics of the tunnel structure. The purpose of this study was to expand the carpal arch in vitro by applying volar forces on the surface of the wrist. METHODS: The mechanism was implemented in eight cadaver hands by attaching a volar force transmitter to the palmar surface of the wrist and pulling the transmitter volarly at six force levels (0, 3, 6, 9, 12, and 15 N). Ultrasound images of the cross section at the distal carpal tunnel were collected for morphological analysis. FINDINGS: The carpal arch height, width, and area were significantly altered by the volarly applied force (P < 0.001). The arch height and area were increased but the arch width was decreased by the force. Pearson's correlation coefficient showed that there was a positive correlation between the arch height and force magnitude; and between the arch area and force magnitude. A negative correlation existed between the arch width and force magnitude (P < 0.001). The magnitude of change of the arch height, width, and area was increased as the force magnitude increased. INTERPRETATION: This study demonstrated that applying external forces on the wrist skin to increase the carpal arch space was feasible. The magnitude of the force influenced its effect on altering the carpal arch. Study limitations include small sample size and inclusion of male specimens. Future in vivo work is needed for clinical translation feasibility.