Citations

Importance Tau positron emission tomography (PET) allows in vivo detection of neurofibrillary tangles, a core neuropathologic feature of Alzheimer disease (AD). Objective To provide estimates of the frequency of tau PET positivity and its associated risk of clinical outcomes. Design, Setting, and Participants Longitudinal study using data pooled from 21 cohorts, comprising a convenience sample of 6514 participants from 13 countries, collected between January 2013 and June 2024. Cognitively unimpaired individuals and patients with a clinical diagnosis of mild cognitive impairment (MCI), AD dementia, or other neurodegenerative disorders were included. Exposures Tau PET with flortaucipir F 18, amyloid-β (Aβ) PET, and clinical examinations. Tau PET scans were visually rated as positive according to a US Food and Drug Administration– and European Medicines Agency–approved method, designed to indicate the presence of advanced neurofibrillary tangle pathology (Braak stages V-VI). Main Outcomes and Measures Frequency of tau PET positivity and absolute risk of clinical progression (eg, progression to MCI or dementia). Results Among the 6514 participants (mean age, 69.5 years; 50.5% female), median follow-up time ranged from 1.5 to 4.0 years. Of 3487 cognitively unimpaired participants, 349 (9.8%) were tau PET positive; the estimated frequency of tau PET positivity was less than 1% in those aged younger than 50 years, and increased from 3% (95% CI, 2%-4%) at 60 years to 19% (95% CI, 16%-24%) at 90 years. Tau PET positivity frequency estimates increased across MCI and AD dementia clinical diagnoses (43% [95% CI, 41%-46%] and 79% [95% CI, 77%-82%] at 75 years, respectively). Most tau PET–positive individuals (92%) were also Aβ PET positive. Cognitively unimpaired participants who were positive for both Aβ PET and tau PET had a higher absolute risk of progression to MCI or dementia over the following 5 years (57% [95% CI, 45%-71%]) compared with both Aβ PET–positive/tau PET–negative (17% [95% CI, 13%-22%]) and Aβ PET–negative/tau PET–negative (6% [95% CI, 5%-8%]) individuals. Among participants with MCI at the time of the tau PET scan, an Aβ PET–positive/tau PET–positive profile was associated with a 5-year absolute risk of progression to dementia of 70% (95% CI, 59%-81%). Conclusions and Relevance In a large convenience sample, a positive tau PET scan occurred at a nonnegligible rate among cognitively unimpaired individuals, and the combination of Aβ PET positivity and tau PET positivity was associated with a high risk of clinical progression in both preclinical and symptomatic stages of AD. These findings underscore the potential of tau PET as a biomarker for staging AD pathology.

Purpose Part-two of this consensus aimed to provide recommendations for the prevention of meniscus injuries, non-operative treatment of acute tears and degenerative lesions, return to sports, and patient-reported outcome measures. Methods This consensus followed the European Society of Knee Surgery, Sports Traumatology and Arthroscopy (ESSKA) formal consensus methodology. For this combined ESSKA- American Orthopedic Society for Sports Medicine (AOSSM) - American Academy of Sports Physical Therapy (AASPT) initiative, 67 experts from 14 countries, including orthopedic surgeons and physiotherapists, were involved. The 26 Steering Group members established guiding questions, screened the existing evidence, and proposed statements, and provided Grades of recommendations. The 41 Rating Group members assessed the statements according to a Likert scale (1-9). Final documents were assessed by an international peer review group for geographical adaptability. Results Low to moderate scientific level of evidence was available, so that grades of recommendations were low (three Grade A ratings, four Grade B, three Grade C and 13 Grade D), underlining the relevance of this consensus. One strong and 17 relative agreements with overall median of 8 (8-9) and a mean of 7.92 +/- 0.37 were achieved for 23 statements on 18 questions. Prevention of meniscus injuries is possible with general knee injury reduction programs and through avoidance of certain activities. Non-Operative treatment including physical therapy is the first line approach for degenerative meniscus lesions and may be an option for some acute tears. Return to sports after meniscus tear surgery should be both criterion-based and time-based. Patient reported outcomes in combination with performance-based measures are recommended to evaluate the rehabilitation process. Conclusion This international EU-US consensus established recommendations for prevention strategies, describes rehabilitation of non-operated patients and of patients after partial meniscectomy, meniscus repair and meniscus reconstruction, and establishes return to sport criteria. These updated and structured recommendations may be applied by surgeons and physiotherapists. Level of Evidence I, Formal Consensus.

Background: Over 2.3 million liposuctions are performed annually with a complication rate of approximately 5%, including a death rate of 1 in 5000 because of blood loss. Artificial intelligence models offer potential for improving blood loss prediction and management in these procedures, analyzing extensive data to identify risk factors and accurately estimate blood loss. Methods: Data from 721 large-volume liposuction patients at 2 centers in Bogotá, Colombia, and Loja, Ecuador, between 2019 and 2023 were evaluated. Both centers followed identical perioperative protocols. The data set was split into training (621 patients) and testing (100 patients) sets. A supervised machine learning model was trained to predict blood loss. Model predictions were compared with clinical data using statistical validation metrics. Results: Most patients were women (79.2%), with median values of age of 37 years; weight, 65 kg; height, 165 cm; body mass index, 24.34 kg/m²; volemia, 3924.41 mL; infiltrated volume, 5800 mL; and aspirated volume, 3900 mL. Previous liposuction was noted in 32%. No significant differences were found between training and testing cohorts. The model achieved a mean absolute error of 22.09 mL, root mean square error of 34.13 mL, and an R ² value of 0.974, indicating high predictive accuracy and excellent model fit. Conclusions: The authors’ study has developed and validated an accurate artificial intelligence–based model to predict blood loss in large-volume liposuction, showing 94.1% accuracy. The authors’ model enhances preoperative planning and intraoperative management, potentially reducing complications and improving outcomes.

Abstract Objective The successful diagnosis and classification of lymphoid neoplasms in blood and bone marrow is the responsibility of the practicing pathologist. This guide provides a general “roadmap” for this process, from initial case recognition to final classification. Methods The integration of hematologic, morphologic, immunophenotypic, and genetic features for the full spectrum of precursor and mature B-cell, T-cell, and natural killer–cell neoplasms that typically manifest in blood and bone marrow is included. Results Classification systems for lymphoid neoplasms provide criteria for pathologists to render a diagnosis that is optimal for patient care, treatment, and outcome prediction. Conclusions This guide provides diagnostic strategies for lymphoid neoplasms encountered in blood and bone marrow specimens using both the International Consensus Classification and the World Health Organization fifth edition classification systems. Key tips are provided for each entity along with testing requirements, differential diagnosis, nonneoplastic mimics, and other unique features based on the experience of the Bone Marrow Pathology Group members.