Citations

Abstract Objective To compare iron deposition in the substantia nigra (SN) as measured with quantitative susceptibility mapping (QSM) on antemortem magnetic resonance imaging (MRI) between individuals with and without Lewy‐related pathology at autopsy. Methods We performed a retrospective cohort study including 54 participants who underwent autopsy and antemortem MRI with QSM. Cases were classified as Lewy body disease (LBD)‐present (n = 13) if they had Lewy‐related pathology and LBD‐absent (n = 41) if they did not have Lewy‐related pathology. QSM was calculated for the whole SN and the two subregions: pars compacta (SNc) and pars reticulata (SNr). Nonparametric Wilcoxon rank‐sum tests were used to compare SN QSM values between LBD‐present and LBD‐absent cases. Area under the receiver operating characteristic (ROC) curve (AUC) analyses tested the accuracy of SN QSM values to distinguish the two groups. Associations of QSM values in the SN and its subregions with clinical features were tested with Spearman's correlations. Results The LBD‐present group had higher QSM values in the SNc ( P = 0.008) than the LBD‐absent group with no differences in SNr. QSM values of the SNc distinguished LBD‐present and LBD‐absent cases with good accuracy (AUC = 0.74) and correlated with the presence of parkinsonism and parkinsonism severity. Conclusions This study provides neuropathological confirmation of the utility of SNc QSM as an in vivo biomarker of Lewy‐related pathology. Imaging evidence of abnormal iron deposition in the SNc could potentially serve as a biomarker for inclusion in emerging research frameworks aimed at defining individuals with LBD based on their biological characteristics. Ultimately, this could facilitate more precise diagnoses and guide treatment strategies in LBD. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Background/Objectives: Autoimmune inner ear disease (AIED) causes sensorineural hearing loss that classically presents as fluctuating, asymmetric loss of hearing. Associated vestibular and other ear symptoms can be present in many patients. First-line treatment of AIED is high-dose corticosteroids. AIED can present either as a primary condition limited to ear involvement or secondary, as part of an underlying systemic autoimmune rheumatic disease, the most common of which include vasculitis and relapsing polychondritis. We described our cohort of primary AIED, including demographics, treatment, and outcomes. We excluded from this review sensorineural hearing loss in the context of vasculitis and relapsing polychondritis. Methods: We performed a chart review of patients with the diagnosis of AIED at Mayo Clinic and compared the cohort by sex. Results: Thirty-one patients met the inclusion criteria. The mean age was 48.5 years, and 17 were men. Patients were initially evaluated at the Department of Otorhinolaryngology or Internal Medicine, and 29 patients were subsequently referred to the Department of Rheumatology, with a mean of 12.2 weeks after the first evaluation. Treatment with corticosteroids showed improvement in hearing and vestibular symptoms during the first month but no further improvement by the end of the third month. Other immunosuppressive medications were used with various degrees of response. Methotrexate was the second most used therapy, with 11 of 17 patients reporting an improvement in symptoms. Conclusions: Corticosteroid therapy is an effective initial treatment for AIED and should be followed with corticosteroid-sparing agents to prevent further damage to the cochlea.

Study Design: Single-center retrospective cohort study. Objective: To determine if the 4-rod construct (4RC) is protective against the occurrence of rod fractures when compared with the 3-rod construct (3RC) in adult spinal deformity (ASD) patients with long fusions to the sacrum. Summary of Background Data: Past studies have explored the different outcomes in subjects with dual-rod versus multirod constructs. There is a lack of literature distinguishing the ramifications of 3RC versus 4RC, particularly in the prevalence of rod fractures and rod fractures requiring subsequent revision surgery as a result of pseudarthrosis. Methods: ASD patients undergoing long instrumented fusions to the sacrum were dichotomized between the 3RC and 4RC cohorts. Outcomes of interest include the occurrence of rod fractures (RFs) and RFs requiring revision (RFR). Two-tailed independent-sample t test with Welch's correction and χ 2 /Fisher exact test were used for continuous and categorical variables, respectively. Multivariable logistic regression analysis was performed to assess whether the 4RC is protective against rod fractures when compared with the 3RC. Results: One hundred forty-five patients with a minimum 2-year follow-up were included (3RC=57, 4RC=88). Four RC had a greater body mass index (BMI) ( P =0.002), longer operating room (OR) time ( P =0.002), greater estimated blood loss (EBL) ( P =0.002), total instrumented levels (TIL) ( P =0.028), and more 3-column osteotomies (3COs) performed ( P =0.028). Four RC had greater baseline coronal vertical axis (CVA) (28.2±24.9 vs. 18.5±16.9 mm, P =0.006) and sagittal vertical axis (SVA) (55.1±64.8 vs. 30.4±41.8 mm, P =0.006). Three RC had a greater rate of RF (28.1% vs. 14.8%, P =0.0506) and RFR (14.9% vs. 10.2%, P =0.486) when compared with 4RC, but these findings were not statistically significant. After controlling for BMI, the use of 3-column osteotomies, total instrumented levels, change in coronal alignment (∆CVA), change in sagittal alignment (∆SVA), use of bone morphogenetic protein, and number of interbody fusions, 3RC was associated with 4.93× greater odds of experiencing RFs ( P =0.0078). However, significance fell short when adjusting for the occurrence of RFR [OR=2.58 (0.60–11.19), P =0.2067]. Conclusion: ASD patients having long fusions to the sacrum with 4RC across the lumbosacral junction are shown to be at lesser risk of developing rod fractures but not revision surgery as compared with 3RC at 2-year follow-up.

Mesenchymal dendritic cell neoplasms represent a distinct category of hematologic malignancies that challenge traditional classifications of histiocytic and classical dendritic/Langerhans cell neoplasms. Historically grouped under the broader umbrella of dendritic cell neoplasms, these entities differ significantly in their ontogeny, histopathologic features, molecular alterations, and clinical behavior. They are categorized into three main subtypes including follicular dendritic cell sarcoma, fibroblastic reticular cell tumor, and EBV-positive inflammatory follicular dendritic cell sarcoma/fibroblastic reticular cell tumor. They originate from mesenchymal stromal cells, and genetic alterations activating the NF- κβ pathway are frequent in follicular dendritic cell sarcomas. Immunophenotypic characterization is critical to distinguish these from other hematologic malignancies including histiocytic and classical dendritic/Langerhans cell neoplasms and other solid (non-hematopoietic) cancers. This review recapitulates current knowledge on existing classifications, details their diverse ontogeny from classical dendritic cell neoplasms, and provides insights into their clinicopathologic characteristics to improve diagnostic accuracy. We detail two case studies that demonstrate the challenges involved in the histopathologic diagnosis of these rare tumors, necessitating a comprehensive workup. Integrating developmental biology into practical diagnostic algorithms is essential to improve recognition and classification of these underdiagnosed neoplasms, ultimately guiding timely management.

Abstract Langerhans cell histiocytosis (LCH) is a rare histiocytic disorder infrequently complicated by delayed-onset pituitary disease. A 41-year-old female presented with papular, acneiform skin lesions. Shave biopsy demonstrated a superficial dermal epithelioid cell proliferation with S100, CD1a, and langerin positivity on immunohistochemistry and a BRAF p.N486_P490del inframe deletion-gain of function pathogenic variant on next-generation sequencing. The skin lesions spontaneously resolved. One year later, she developed progressive fatigue, fevers, anorexia, menstrual irregularities, polyuria, and polydipsia. Laboratory workup was consistent with panhypopituitarism. Pituitary magnetic resonance imaging noted mass-like thickening and enhancement of the infundibulum extending toward the hypothalamus. After treatment with cobimetinib, magnetic resonance imaging findings resolved but endocrinopathies persisted, requiring indefinite hormone therapy. This case demonstrates the full spectrum of endocrinopathies of LCH-induced pituitary disease and is an unusual circumstance of LCH with delayed-onset panhypopituitarism.

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.

Abstract INTRODUCTION Temporal cortical microstructural changes precede cortical atrophy during memory decline. We used neurite orientation dispersion and density imaging (NODDI) to assess such early microstructural change. METHODS Cognitively unimpaired (CU, n = 725) and mildly cognitively impaired (MCI, n = 111) participants from the Mayo Clinic Study of Aging underwent 3T magnetic resonance imaging (MRI), including NODDI and neuropsychological evaluation for calculation of memory z scores. Linear mixed effects modelling assessed the relationship between temporal cortical Neurite Density Index (NDI), Orientation Dispersion Index (ODI), and both baseline and mean annual change in memory z scores. RESULTS NDI was significantly associated with both baseline memory z scores and mean annual change of memory z scores, in the hippocampi and amygdalae. Similar significant associations with ODI were seen in hippocampi, parahippocampal, and fusiform gyri. DISCUSSION Temporal cortical NDI and ODI are early imaging biomarkers of cortical microstructural integrity that may predict memory decline in CU and MCI individuals. Highlights We imaged 836 participants in the Mayo Clinic Study of Aging, who were either cognitively unimpaired (CU) or suffered from mild cognitive impairment (MCI). Neurite orientation dispersion and density imaging (NODDI) is an advanced diffusion magnetic resonance imaging (MRI) technique We found significant associations between new NODDI imaging biomarkers of microstructural integrity and memory function in CU and MCI individuals These relationships were both cross‐sectional in nature and associated with future memory decline Future application of NODDI imaging biomarkers in the setting of anti‐amyloid monoclonal antibody therapy may provide greater insight into memory decline than current cortical atrophy measures.

Objective: To evaluate the first 3 years of compliance with the American College of Surgeons Commission on Cancer (CoC) Operative Standards. Background: CoC implemented evidence-based standards to improve the quality of sentinel lymph node biopsy and axillary lymph node dissection for breast cancer (operative standards 5.3 and 5.4), wide local excision for melanoma (5.5), colectomy for colon cancer (5.6), proctectomy for rectal cancer (5.7), and pulmonary resection for lung cancer (5.8) at ∼1400 programs treating >74% of US cancer patients. Each operative standard defines a technical element of the operation and structured documentation. Methods: Compliance data are from site visits conducted between January 1, 2022, and December 31, 2024 (implementation/site visits began in 2021/2022 for 5.7 and 5.8 and 2023/2024 for 5.3–5.6). Compliance with each operative standard was determined by evaluation of 7 operative (5.3–5.6) or pathology (5.7, 5.8) reports. Deficiency in technical performance, documentation, or both was considered noncompliance. Results: Reviewers conducted 974 site visits of Comprehensive Community (44%), Community (23%), Academic Comprehensive (16%), network (12%), NCI-Designated Comprehensive (4%), and other (1%) cancer programs. Program compliance rates ranged from 53% to 88%. Documentation noncompliance was more common for standards 5.3 to 5.6 (based on operative reports), and technical noncompliance was more common for 5.7 and 5.8 (based on pathology reports). Compliance significantly (P=0.006) varied by program type for 5.8 (highest: 66% at NCI-designated Comprehensive programs; lowest: 37% at Community Cancer programs). Conclusions: Early compliance with CoC operative standards varied, indicating local and large-scale national quality improvement efforts are needed.

Abstract Photon-counting detector CT (PCD-CT) represents a significant advancement in medical imaging, particularly for musculoskeletal (MSK) applications. Its primary innovation lies in enhanced spatial resolution, which facilitates improved detection of small anatomical structures such as trabecular bone, osteophytes, and subchondral cysts. PCD-CT enables high-quality imaging with reduced radiation doses, making it especially beneficial for populations requiring frequent imaging, such as paediatric patients and individuals with multiple myeloma. Additionally, PCD-CT supports advanced applications like bone quality assessment, which correlates well with gold-standard tests, and can aid in diagnosing osteoporosis and assessing fracture risk. Techniques such as spectral shaping and virtual monoenergetic imaging further optimize the technology, minimizing artefacts and enhancing material decomposition. These capabilities extend to conditions like gout and haematologic malignancies, offering improved detection and assessment. The integration of artificial intelligence could enhance PCD-CT’s performance by reducing image noise and improving quantitative assessments. Ultimately, PCD-CT’s superior resolution, reduced dose protocols, and multi-energy imaging capabilities will likely have a transformative impact on MSK imaging, improving diagnostic accuracy, patient care, and clinical outcomes.