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    Microstructural White Matter Alterations in Pediatric Idiopathic Intracranial Hypertension: A Diffusion Tensor Imaging Study
    (Mdpi, 2025) Ozgor, Bilge; Ayvaz, Huseyin; Tan, Mahir; Demiroz Tasolar, Sevgi; Yucel, Gul; Bicakcioglu, Isinsu; Gungor, Serdal
    Highlights What are the main findings? Fractional anisotropy values in the optic radiation and posterior limb of the internal capsule were significantly reduced in pediatric idiopathic intracranial hypertension, indicating microstructural white matter alterations detectable by diffusion tensor imaging. DTI metrics-particularly FA-demonstrated strong discriminative accuracy (AUC = 0.83) for distinguishing affected patients from healthy controls, outperforming conventional MRI markers. What are the implications of the main findings? DTI may serve as a complementary tool to conventional MRI in the diagnostic evaluation of pediatric IIH, providing quantitative insights into pressure-related white matter changes. These findings suggest that advanced diffusion imaging could aid early detection and monitoring of intracranial pressure-related alterations, warranting validation in larger, prospective pediatric cohorts.Highlights What are the main findings? Fractional anisotropy values in the optic radiation and posterior limb of the internal capsule were significantly reduced in pediatric idiopathic intracranial hypertension, indicating microstructural white matter alterations detectable by diffusion tensor imaging. DTI metrics-particularly FA-demonstrated strong discriminative accuracy (AUC = 0.83) for distinguishing affected patients from healthy controls, outperforming conventional MRI markers. What are the implications of the main findings? DTI may serve as a complementary tool to conventional MRI in the diagnostic evaluation of pediatric IIH, providing quantitative insights into pressure-related white matter changes. These findings suggest that advanced diffusion imaging could aid early detection and monitoring of intracranial pressure-related alterations, warranting validation in larger, prospective pediatric cohorts.Abstract Background/Objectives: Idiopathic intracranial hypertension (IIH) is an uncommon but clinically important cause of elevated intracranial pressure in children. Conventional MRI findings such as perioptic subarachnoid space (SAS) distension and posterior globe flattening are helpful but may lack sensitivity or specificity in certain cases. Diffusion tensor imaging (DTI), which quantifies white matter microstructure through metrics such as fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD), offers additional diagnostic potential, yet its role in pediatric IIH remains insufficiently defined. Methods: This retrospective case-control study included 26 pediatric patients with IIH and 26 age- and sex-matched controls who underwent brain MRI with DTI between 2010 and 2025. DTI parameters were measured in major white matter tracts, and conventional MRI findings associated with raised intracranial pressure were recorded. Associations between DTI metrics and conventional imaging markers were analyzed using standardized statistical tests. Results: Children with IIH demonstrated significantly reduced FA and increased MD and RD values in several key white matter regions, particularly within the optic radiation, splenium of the corpus callosum, and posterior limb of the internal capsule. FA values showed a negative correlation with perioptic SAS width, while RD and MD were positively correlated with posterior globe flattening and empty sella grade. Receiver operating characteristic analysis identified FA in the optic radiation as the strongest discriminator between IIH and controls (AUC = 0.83). Inter-observer reliability for FA measurements was excellent (ICC = 0.91). Conclusions: Pediatric IIH appears to be associated with pressure-related microstructural alterations in white matter, detectable through DTI. Among the diffusion metrics, FA demonstrated the strongest diagnostic potential and may serve as a complementary tool to conventional MRI. Validation in larger, prospective pediatric cohorts is required to establish its clinical utility.
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    Pan-immune-inflammation value as a predictor of loss of ambulation in duchenne muscular dystrophy: a retrospective cohort study
    (Bmc, 2026) Ozgor, Bilge; Bicakcioglu, Isinsu; Tan, Mahir; Yucel, Gul; Karadag, Meral; Gungor, Serdal
    Background Duchenne muscular dystrophy (DMD) is a progressive X-linked neuromuscular disorder marked by early functional decline and considerable variability in the timing of loss of ambulation (LOA). Readily accessible biomarkers to predict this decline remain limited. The pan-immune-inflammation value (PIV ), derived from routine blood counts, has been studied in various inflammatory conditions, but its relevance in DMD is not yet well defined. Methods This retrospective cohort study included 86 children and adolescents with genetically or biopsy-confirmed DMD followed between 2010 and 2025. Baseline neutrophil, lymphocyte, monocyte and platelet counts were used to calculate PIV and other systemic inflammation indices (NLR, PLR, MLR, SII, SIRI). Results Fifty-two patients (60.5%) experienced LOA during follow-up. Those who developed LOA had significantly higher neutrophil (4.6 +/- 1.8 vs. 3.4 +/- 1.2 & times; 10(9)/L, p = 0.001), monocyte (0.58 +/- 0.20 vs. 0.46 +/- 0.14 & times; 10(9)/L, p = 0.006) and platelet counts (351 +/- 82 vs. 308 +/- 65 & times; 10(9)/L, p = 0.02), along with lower lymphocyte counts (2.7 +/- 0.8 vs. 3.4 +/- 0.7 & times; 10(9)/L, p < 0.001). Median PIV was higher in the LOA group (312.5 [256-412] vs. 158.7 [106-209], p < 0.001). In ROC analysis, PIV showed the highest discriminative performance (AUC = 0.84; 95% CI, 0.76-0.91) compared with NLR, PLR, MLR, SII and SIRI. In multivariable Cox regression, PIV was independently associated with earlier LOA (HR = 1.42 per 100-unit increase; 95% CI, 1.18-1.72; p < 0.001). Age-stratified analyses suggested a stronger association between elevated PIV and earlier LOA in younger children (2-6 and 7-9 years; p = 0.006 and p = 0.018), whereas this association did not reach statistical significance in patients aged >= 10 years. Conclusion In this cohort, PIV was significantly associated with loss of ambulation and demonstrated higher discriminative performance than other hematologic inflammation indices. The observed age-dependent pattern suggests that elevated PIV at younger ages may be linked to early inflammatory activity relevant to disease progression. However, given the retrospective design, exploratory subgroup analyses, and the multifactorial nature of DMD, these findings should be interpreted with caution. PIV may represent an adjunctive and accessible marker or early risk stratification, but larger prospective studies with longitudinal inflammatory assessment are required to validate its prognostic value and clarify its role in clinical practice