Category: Statistics

Clin Imaging. 2026 May 28;136:110854. doi: 10.1016/j.clinimag.2026.110854. Online ahead of print.

ABSTRACT

PURPOSE: To evaluate the association between clinical and MRI characteristics and histological outcomes of MRI-guided vacuum-assisted biopsies (MVAB) performed in the lumpectomy bed after malignant breast-conserving surgery (BCT).

MATERIAL AND METHODS: This retrospective study analyzed all MVABs performed in malignant lumpectomy beds between 2016 and 2022, evaluating the relationship between demographic and imaging characteristics and pathological outcomes (benign vs. malignant) using appropriate statistical methods.

RESULTS: Malignancy was diagnosed in 14 of 72 biopsies (19%), most commonly invasive ductal carcinoma (50%). Fat necrosis was the predominant benign finding (38%). On univariate analysis, benign outcomes were more frequent in younger patients (median 60 vs. 69 years), those with prior radiation therapy (90% vs. 69%, P = 0.048), lesions adjacent to a postoperative cavity (28% vs. 7%, P = 0.1), and when coarse calcifications were present on mammography (43% vs. 0%, P = 0.011). Benign results were also more common for biopsies performed within one year or beyond six years after lumpectomy (97%, P = 0.087). No MRI morphological or kinetic features reliably distinguished benign from malignant lesions.

CONCLUSION: MVAB of lumpectomy bed lesions yielded a 19% malignancy rate, with benign outcomes often associated with specific clinical and imaging features. Larger studies are warranted to validate these findings and refine patient selection.

PMID:42224832 | DOI:10.1016/j.clinimag.2026.110854

Artif Intell Med. 2026 Jun 1;180:103462. doi: 10.1016/j.artmed.2026.103462. Online ahead of print.

ABSTRACT

Machine learning (ML) is transforming healthcare, but safe clinical decisions demand reliable uncertainty estimates that standard ML models fail to provide. Conformal prediction (CP) is a popular tool that allows users to turn heuristic uncertainty estimates into uncertainty estimates with statistical guarantees. CP works by converting predictions of a ML model, together with a calibration sample, into prediction sets that are guaranteed to contain the true label with any desired probability. An often cited advantage is that CP theory holds for calibration samples of arbitrary size, suggesting that uncertainty estimates with practically meaningful statistical guarantees can be achieved even if only small calibration sets are available. We question this promise by showing that, although the statistical guarantees hold for calibration sets of arbitrary size, the practical utility of these guarantees does highly depend on the size of the calibration set. This observation is relevant in medical domains because data is often scarce and obtaining large calibration sets is therefore infeasible. We corroborate our critique in an empirical demonstration on a medical image classification task.

PMID:42224800 | DOI:10.1016/j.artmed.2026.103462

Comput Methods Programs Biomed. 2026 May 28;284:109469. doi: 10.1016/j.cmpb.2026.109469. Online ahead of print.

ABSTRACT

BACKGROUND AND OBJECTIVE: Pediatric patients with myocarditis present with heterogeneous symptoms, disease courses and outcomes. Late Gadolinium Enhancement (LGE) in cardiovascular magnetic resonance imaging (CMR) is a routine diagnostic tool, but relationships between LGE patterns and patient characteristics are typically assessed qualitatively. We investigate the use of radiomic features to quantify LGE texture and location to identify signatures that stratify pediatric myocarditis cases.

METHODS: We compared radiomic features in a digital phantom across different resampling strategies to address variability in patient size and imaging parameters. Non-negative matrix factorization (NMF) was applied to spatially resolved radiomic features of the left myocardium to identify distinct radiomic signatures in a pediatric cohort with confirmed myocarditis. Clinical parameters were compared across the resulting groups, and correlations between image meta-features and outcomes explored. A user-friendly software tool offers feature extraction and signature calculation on unseen data and comparison of new patients to the existing cohort.

RESULTS: The phantom experiments showed improved comparability of radiomic features when resampled to uniform voxel density (voxel count per myocardial diameter) rather than uniform voxel size. After appropriate pre-processing, NMF identified four patient groups with distinct LGE signatures within 195 patients (median age 16 years, 19% female). One group separates out patients with signs of heart failure, correlating with left-ventricular ejection fraction (r=-0.38, 95% CI [-0.50,-0.25]) and log(NT-proBNP) (r=0.36,[0.21,0.50]). A second group’s dominant meta-feature correlates with myocardial edema (r=0.27,[0.13,0.40]) and ventricular tachycardia (r=0.19,[0.05,0.32]); a third indicates mild presentation. The clinical relevance of the fourth remains unclear.

CONCLUSIONS: Spatially resolved radiomic features from suitably resampled LGE CMR images yield quantitative LGE signatures associated with clinical characteristics in pediatric myocarditis, supporting improved stratification and personalized management in the long run.

PMID:42224791 | DOI:10.1016/j.cmpb.2026.109469

Injury. 2026 May 26;57(8):113386. doi: 10.1016/j.injury.2026.113386. Online ahead of print.

ABSTRACT

BACKGROUND: Pediatric radial neck fractures, though rare, pose significant management challenges with several treatment options. Open reduction is typically used for more complex cases, where greater fracture severity may contribute to higher complication rates and poorer outcomes. This study aims to evaluate functional outcomes, complications, and risk factors in a large cohort of pediatric patients treated with open reduction, performed after unsuccessful closed reduction.

METHODS: A retrospective cohort study was conducted on 53 pediatric patients (mean age 8 years) with radial neck fractures (Judet 4) treated surgically with open reduction, performed after unsuccessful closed reduction, at a single institution between March 2014 and October 2024. Data on surgical delay, complications, and functional outcomes (Oxford Elbow Score) were collected. Statistical analyses included correlation tests, t-tests, and multivariate regression models to assess predictors of outcomes and complications.

RESULTS: The mean Oxford Elbow Score was 96, indicating excellent functional outcomes. Complications occurred in 13.5% of patients, including heterotopic ossification (9.6%), posterior interosseous nerve injury (1.9%), and avascular necrosis (1.9%). Surgical delay was significantly longer in patients with complications (p = 0.038). Multivariate analysis revealed that complications were the most significant predictor of poorer functional outcomes (β = -17.12, p < 0.001), while the surgical delay did not significantly impact outcomes or complication rates.

CONCLUSION: Open reduction, performed after unsuccessful closed reduction, for pediatric severe radial neck fractures yields excellent functional outcomes with a low complication rate. Complications, such as heterotopic ossifications, are the primary determinant of poor outcomes, whereas surgical delay and age do not significantly affect results.

LEVEL OF EVIDENCE: Level III – Retrospective cohort study.

PMID:42224787 | DOI:10.1016/j.injury.2026.113386

Injury. 2026 May 26;57(8):113387. doi: 10.1016/j.injury.2026.113387. Online ahead of print.

ABSTRACT

BACKGROUND: Pelvic fractures, although relatively uncommon, are associated with high economic burden, morbidity, and mortality. Mortality is largely driven by severe associated injuries and high-energy mechanisms. While predictors of mortality are well established, their local applicability for the study institution has not been updated using site-specific data since an earlier regional study (2001-2008). As trauma management protocols have evolved, this study utilizes prediction model development and internal validation-adhering to the TRIPOD guidelines-to update the prognostic value of these established predictors within our institutional context by using site-specific data.

METHODS: Data from July 2010 – December 2022 were sourced from a Level I adult Major Trauma Centre’s registry. The cohort included patients > =15 years old with Injury Severity Score (ISS)> 12 and pelvic fractures. In-hospital mortality was the outcome of interest. Model development utilized backward elimination for predictor selection into a multivariable logistic regression model, with internal validation via bootstrap methods. Model performance was assessed using the Brier scaled score, and discrimination (c-statistic), and calibration (calibration plot).

RESULTS: Out of 1564 included patients, 118 were non-survivors (mortality rate 7.5%). The optimism-adjusted prediction model identified ISS≥ 50 (OR 7.4), age≥ 65 (OR 6.1), and severe head injury (OR 3.6) as strong predictors of mortality. Additional predictors with ORs between 2-3 included ISS 25-49, shock on admission, direct transport from the scene of injury, and severe comorbidity. The model demonstrated good to excellent discrimination with an optimism-adjusted c-statistic of 0.88.

CONCLUSIONS: This study developed and internally validated a prediction model for in-hospital mortality in major trauma patients with high-energy pelvic fractures using recent, single-center data, identifying key predictors. Notably, the severity of the pelvic fracture itself was not an independent predictor, indicating that pelvic injuries act primarily as markers of overall systemic injury severity. While optimism-adjusted odds from internal validation were attenuated, the findings remain comparable to the broader literature. External validation is recommended to assess the model’s transportability and broader applicability.

PMID:42224785 | DOI:10.1016/j.injury.2026.113387

Injury. 2026 May 30;57(8):113382. doi: 10.1016/j.injury.2026.113382. Online ahead of print.

ABSTRACT

BACKGROUND: The Intramedullary fixation of unstable intertrochanteric fractures is usually performed using the proximal femoral nail anti-rotation (PFNA), but the problems of optimal insertion point of intramedullary nail and anterior cortical impingement have not been solved.Meanwhile, the variation of the femoral neck-shaft angle (NSA) may also result in the deviation of the PFNA’s insertion point. The purpose of this study to determine the ideal intramedullary nail placement position in the treatment of intertrochanteric fractures through the three-dimensional (3D) models, and to investigate the relationship between the differences in the RFC and the selection of intramedullary nail length when the ideal insertion position is established.

METHODS: We retrospectively collected the femur computed tomography (CT) scans of 200 adults, and the DICOM-format CT scan images of each patient were imported into Mimics software to creat virtual femoral models. By inserting the PFNA into the femoral model, we recorded the length of each femur model and the neck-shaft angle (NSA); the vertical distance between each bony landmark and the optimal insertion point were measured in the projected plane;the distance of the insertion point to the apex of the greater trochanter (L2); the distance of the insertion point to the vastus lateralis muscle ridge (L3); the distance of the insertion point to the insertion of piriformis tendon (L4); the vertical distance between the optimal insertion point and the apex of the trochanter in the sagittal plane (L5) and the vertical distance in the coronal plane (L6); the radius of femoral curvature (RFC).

RESULTS: The mean distance of the insertion point to the apex of the greater trochanter (L2) was 8.85±2.49 mm; the mean distance of the insertion point to the vastus lateralis muscle ridge (L3) was 21.88±3.57 mm; the mean distance of the insertion point to the insertion of piriformis muscle (L4) was 16.38±3.33 mm. The optimal insertion point for the intramedullary nail is primarily located in the anterolateral region of the apex of the femoral greater trochanter.the mean of the length of each femur model (L1) was 390.37±30.47 mm; the mean neck-shaft angle (NSA) was 128.01±7.59°; the mean radius of femoral curvature (RFC) was 841.88±125.64 mm;the mean vertical distance between the optimal insertion point and the apex of the trochanter in the sagittal plane (L5) was 5.51±2.05 mm. For the data captured above, L1, NSA, RFC, L5 of the intersex difference was significant (P < 0.05). There was a significant positive correlation (r² =0.4851,p < 0.0001) between L5 and the NSA in males;there was a significant positive correlation(r² =0.5267, p < 0.0001) between L5 and the NSA in females. The mean RFC of medullary cavities compatible and incompatible for the PFNA (intramedullary nail lengths of 240 mm) in males were 990.68±75.76 mm, 817.37±79.57 mm and in females were 1032.92±105.53 mm, 770.44±88.69 mm. For the data captured above,the effect of the RFC on whether the PFNA (intramedullary nail lengths of 240 mm) could match the medullary cavity in females and males was statistically significant. Meanwhile,the mean RFC of medullary cavities compatible for the PFNA (intramedullary nail lengths of 240 mm) was statistically significant between males and females (P < 0.05).

CONCLUSIONS: This study provide theoretical and data support for the optimal insertion point of the PFNA and the feasibility of inserting the longer PFNA in different femurs by the 3D simulation. Preoperative three-dimensional reconstruction was utilized to develop individualized treatment plans,and data from 3D model need to be combined with clinical experience for more safely inserting intramedullary nail into the medullary cavity. Further biomechanical tests and clinical studies are needed to verify its effects.

PMID:42224783 | DOI:10.1016/j.injury.2026.113382

J Hazard Mater. 2026 May 17;514:142407. doi: 10.1016/j.jhazmat.2026.142407. Online ahead of print.

ABSTRACT

Remediation costs are closely tied to the volume of contaminated soil; therefore, accurate plume estimation is critical for cost-effective risk management. However, most of the contaminated sites yield small-size and zero-inflated datasets, which present unique challenges for statistical analysis and plume estimation. These conditions severely limit the performance of traditional geostatistical approaches such as Kriging, which is highly sensitive to borehole number, spatial placement, and depth-specific replicates and may inadequately characterize plume features under strong heterogeneity and preferential flow. This study adapts the Integrated Nested Laplace Approximation with a Stochastic Partial Differential Equation (INLA-SPDE) framework to estimate PHC plume volume and mass (benzene and the CCME F1 fraction) and incorporates a tracer covariate to represent preferential flow effects. This study extends INLA-SPDE from general soil-property mapping to contaminant plume estimation. Using three synthetic plumes with known geometry and two real remediation sites, we compared the performance of the INLA-SPDE, Hurdle and Kriging models. Across 100 Monte Carlo runs, the INLA-SPDE model produced robust plume estimates with as few as five boreholes under conditions of high vertical resolution (3-4 incremental vertical samples), presence of at least one high-concentration borehole (>100 mg kg^-1), and relatively continuous plume geometry. Moreover, this study found that addressing vertical heterogeneity is more effective for plume estimation than increasing borehole density. The tracer covariate notably improved predictions for the more hydrophobic and strongly sorbing CCME F1 fraction, with limited benefit for the more mobile benzene. Overall, this framework supports cost-effective remediation planning and regulatory decision-making under limited and zero-inflated data conditions.

PMID:42224766 | DOI:10.1016/j.jhazmat.2026.142407

Neural Netw. 2026 May 25;203:109180. doi: 10.1016/j.neunet.2026.109180. Online ahead of print.

ABSTRACT

This study delves into the challenge of achieving optimal synchronization control for time-delayed stochastic dynamic networks through fuzzy reinforcement learning (FRL), underpinned by a novel event-triggered strategy. Traditionally, optimal control is determined by solving the Hamilton-Jacobi-Bellman (HJB) equation. However, the strong nonlinearity and uncertain dynamics inherent in such systems render the solution of the HJB equation particularly arduous. To address this problem, an adaptive FRL algorithm is formulated within an identifier-critic-actor framework, which is derived from the negative gradient of simple adaptive functions. This approach yields a relatively straightforward optimal synchronization controller that eliminates the need for the persistent excitation condition. Subsequently, fuzzy logic systems (FLSs) are designed to approximate unknown uncertainties. A dynamics-estimating identifier and critic/actor FLSs are designed for performance evaluation and control signal generation, respectively. Moreover, a dynamic event-triggered optimal control (DETOC) is proposed. In this strategy, the triggering threshold is adaptively adjusted in real time, effectively reducing communication overhead and computational load. Notably, the optimal control policy is directly approximated by the FRL, bypassing the need to solve the HJB equation. Specifically, the value function is approximated by the critic FLSs for performance evaluation, while the control signal is directly generated by the actor FLSs based on the current system state. Finally, within the FRL-driven DETOC mechanism, the developed control method ensures that all synchronization error signals remain bounded. Its effectiveness is thoroughly verified and demonstrated through simulation examples.

PMID:42224750 | DOI:10.1016/j.neunet.2026.109180

Neurosurg Focus. 2026 Jun 1;60(6):E3. doi: 10.3171/2026.2.FOCUS251085.

ABSTRACT

OBJECTIVE: The aim of this study was to assess whether endonasal endoscopic gross-total resection (GTR) of pediatric craniopharyngioma invading the hypothalamus is associated with increased morbidity compared with subtotal resection (STR).

METHODS: Medical records were reviewed for all pediatric patients (age ≤ 21 years) with craniopharyngioma removed via an endonasal endoscopic approach (EEA) between 2006 and 2024. The Sainte-Rose hypothalamic involvement score (HIS) was used to quantify hypothalamic invasion and to assess its correlation with outcome.

RESULTS: Overall, 23 patients (14 male, mean age 11.2 years) met inclusion criteria, with a mean follow-up of 5.6 years. Five, 9, and 9 patients had an HIS of 0, 1, and 2, respectively. Eleven patients underwent GTR, for which the HIS was 0 (n = 3), 1 (n = 4), and 2 (n = 4). GTR and HIS were not associated with new panhypopituitarism, postoperative diabetes insipidus, visual decline, delayed return to school, or decreased academic performance. Preoperative HIS was not significantly associated with BMI increase (HIS 0 [+13.17%], HIS 1 [+23.29%], and HIS 2 [+40.13%], p = 0.36), and neither was extent of resection (GTR [+6.30] and STR [+6.24]). Tumors recurred in 1 of 11 patients (9%) with GTR and 3 of 12 (25%) with STR, without a statistically significant difference.

CONCLUSIONS: In this small series of pediatric patients with craniopharyngioma removed with EEA, GTR was not associated with increased BMI or increased morbidity. There was an increase in BMI that was larger in higher preoperative HIS cases, indicating that morbidity might arise from tumor infiltration into the hypothalamus and not due to the aggressiveness of the surgery. The surgical strategy for treating pediatric craniopharyngioma might need to be reconsidered in the endoscopic era.

PMID:42224721 | DOI:10.3171/2026.2.FOCUS251085

Neurosurg Focus. 2026 Jun 1;60(6):E4. doi: 10.3171/2026.2.FOCUS251137.

ABSTRACT

OBJECTIVE: The authors present a single-institution experience of patients with large and giant pediatric craniopharyngiomas (CPs) who underwent the extended endoscopic endonasal approach (EEA) at their institution over a 6-year period.

METHODS: Twenty-two consecutive patients ≤ 18 years of age with large (≥ 3 cm) or giant (≥ 5 cm) CPs were treated with EEA between 2016 and 2022 at Rady Children’s Health, San Diego. Clinical outcomes, rates of recurrence, and time to proton therapy were evaluated. Descriptive analyses and Fisher’s exact tests were used to compare categorical variables. A p value < 0.05 was considered statistically significant. The authors performed a literature review to compare their series to historical control outcomes.

RESULTS: Twenty-two patients presenting with large or giant adamantinomatous CP met inclusion criteria (10 males; mean age 9.3 years, range 3.4-17.8 years). Tumor size (mean 4.7 ± 1 cm) was classified as large (≥ 3 cm, n = 14) or giant (≥ 5 cm, n = 8). Twenty (91%) patients achieved gross-total resection, including 7 of 8 (88%) giant tumors and 13 of 14 (93%) large tumors. Of 12 (54%) patients who presented with visual impairment, 7 (58%) improved postoperatively, 4 (33%) remained unchanged, and 1 (8%) worsened postoperatively. Preoperatively, 21 (95%) had a normal motor examination and 20 (91%) had no cranial nerve deficit, while postoperatively, 1 patient developed a new motor deficit and 1 patient developed a new cranial nerve deficit. All patients included had some degree of neuroendocrine compromise postoperatively. Recurrence was observed in 4 of 8 (50%) giant tumors and 5 of 14 (36%) large tumors, with an overall recurrence rate of 41%. Six (27%) patients received proton therapy with a mean delay of 25.7 months (SD 12.4 months). There were no significant differences in clinical features or outcomes between large and giant tumors.

CONCLUSIONS: Endonasal resection of large and giant pediatric CPs is feasible in an experienced multidisciplinary center and can result in avoidance or significant delay of postoperative proton radiation therapy, minimizing the risk of associated neurological and endocrinological late effects. Resection rates and complication profiles are similar to those in the existing peer-reviewed literature.

PMID:42224719 | DOI:10.3171/2026.2.FOCUS251137