Berna Ucan

Introduction. RNU4ATAC-opathy is a rare autosomal recessive disorder characterized by a wide clinical spectrum, including brain anomalies, seizures, strokes, immunodeficiency, and cardiac defects. Other manifestations include ophthalmologic, dermatologic, renal, gastrointestinal, auditory, and endocrine involvement. Here, we report the identification of pathogenic RNU4ATAC variants through whole exome sequencing in an infant presenting with microcephaly, growth failure, and immunodeficiency. Case Presentation. We describe an 11-month-old infant who had been followed since 4 months of age for growth failure and developmental delay. During follow-up, the patient experienced episodes of neurological deterioration triggered by febrile illnesses associated with SARS-CoV-2 and respiratory syncytial virus infections (RSV) at 9 and 11 months of age, respectively. Immunological evaluation showed normal immunoglobulin levels, a marked reduction in switched memory and memory B cells, impaired T-cell activation, and decreased T-cell subpopulations, suggesting combined immunodeficiency that may have contributed to increased susceptibility to viral infections. Whole exome sequencing subsequently identified compound heterozygous pathogenic variants in the RNU4ATAC gene, confirming the diagnosis of RNU4ATAC-opathy. Discussion. RNU4ATAC-opathy should be considered in cases with microcephaly, growth failure, immunodeficiency, and skeletal abnormalities. Our case shows that RNU4ATAC-opathy may present as infection-related encephalopathy, together with combined T- and B-cell dysfunction. Early immunological assessment and timely initiation of prophylactic therapy could play a key role in improving survival. Genetic and immunological evaluations are essential for accurate diagnosis, early intervention, and effective management. Further research is needed to clarify the syndrome’s impact on immune function and guide targeted therapies.

Malformations of cortical development (MCDs) are heterogeneous neurodevelopmental disorders resulting from abnormalities in neuronal proliferation, migration, and post-migrational organization, and they represent an important cause of pediatric epilepsy. High-resolution magnetic resonance imaging (MRI), particularly three-dimensional fluid-attenuated inversion recovery (3D-FLAIR), improves the detection of subtle cortical abnormalities such as focal cortical dysplasia (FCD).This study aimed to describe the distribution, clinical characteristics, and epilepsy-related features of malformations of cortical development in children, and to evaluate the added value of 3D FLAIR MRI in the detection and characterization of focal cortical dysplasia. A total of 47 pediatric patients were included. Post-migrational abnormalities were the most common findings (74.4%), followed by migration disorders (21.2%) and abnormalities of proliferation or apoptosis (4.2%). Seizures were the most frequent presenting symptom, and FCD was the most common subtype. Among the 17 patients with FCD, four lesions not visible on routine imaging were detected using the 3D-FLAIR sequence. In conclusion, MCDs are an important cause of pediatric epilepsy. High-resolution MRI, particularly 3D FLAIR imaging, improves the detection of subtle cortical abnormalities, especially focal cortical dysplasia. Optimized MRI protocols using widely available 1.5-T systems may significantly enhance diagnostic accuracy and support therapeutic planning.

Short stature is clinically and genetically heterogeneous, and defects in the extracellular matrix of growth plate cartilage represent a key disease mechanism. ACAN encodes aggrecan, the major proteoglycan of the growth plate cartilage extracellular matrix. Heterozygous ACAN variants are a recognized cause of familial short stature, often associated with advanced bone age and early growth cessation, yet they show a broad phenotypic spectrum. We aimed to delineate the clinical and molecular spectrum of ACAN ‐related short stature in a Turkish cohort. We retrospectively reviewed 47 individuals from 20 unrelated families with short stature (height ≤ −2 SDS) or predicted adult height < −2 SDS. Anthropometric data, dysmorphic and musculoskeletal findings, radiologic assessments, and molecular genetic results were analyzed. Among 47 individuals (20 females, 27 males), 59.6% were children. Common clinical features included a high forehead, upslanted palpebral fissures, a depressed nasal bridge, low‐set anteverted ears, mild pectus deformity, and brachydactyly. Osteochondritis dissecans, early‐onset osteoarthritis, and advanced bone age were identified in 6.5%, 8.7%, and 28.6% of individuals, respectively. Vertebral findings included scoliosis (19.6%), increased lumbar lordosis (13%), and vertebral endplate changes (10.9%). Genetic testing revealed 15 heterozygous ACAN variants (2 previously reported in ClinVar; 13 novel): 6 nonsense, 2 splice‐site, 5 frameshift, and 2 missense. Overall, 45 patients carried pathogenic/likely pathogenic variants (14 variants), and 2 carried VUS (1 variant). ACAN ‐related short stature represents an important subset of familial short stature. Skeletal and musculoskeletal findings may aid diagnosis, but advanced bone age is not consistent and bone age is often appropriate for chronological age.

Aims: Pediatric non-traumatic intracranial hemorrhage (pNTIH) is an important cause of acute neurological morbidity with an etiological spectrum distinct from that of adults. This study aimed to evaluate the imaging findings, etiological distribution, and age-related characteristics of pNTIH in children.Methods: This retrospective, single-center study included 56 pediatric patients aged 0-18 years who were diagnosed with pNTIH between September 2022 and January 2026. Radiological evaluation included computed tomography (CT), magnetic resonance imaging (MRI), and advanced vascular imaging modalities, including CT angiography (CTA), MR angiography (MRA), and digital subtraction angiography (DSA). Etiologies were determined using a combination of clinical, laboratory, and imaging findings.Results: Arteriovenous malformation (AVM) was the most common etiology (23.2%), followed by cerebral aneurysm (14.3%) and venous ischemia-related hemorrhage (12.5%). AVM, venous ischemia, and cavernoma-related hemorrhages were more common in older children, whereas treatment related hemorrhage was more frequent in infants. Increasing age was associated with a higher likelihood of AVM-related hemorrhage (OR=1.14; 95% CI, 1.01-1.29; p=0.032). CTA was performed in 71.4% of patients, MRA in 53.6%, and DSA in 26.8%. Early mortality occurred in 3 patients (5.4%).Conclusion: Non-traumatic intracranial hemorrhage in children demonstrates age-dependent etiological variation. Early multimodality imaging is essential for accurate etiological diagnosis and timely management.

Objective: Chiari 1 malformation is a congenital anomaly characterized by downward displacement of the cerebellar tonsils through the foramen magnum. Surgical decision-making in Chiari 1 largely depends on clinical symptoms and imaging findings, particularly the presence of headache and syringohydromyelia. This study aimed to evaluate the radiological characteristics and postoperative imaging changes in pediatric patients with Chiari 1 and Chiari 1.5 malformations. Material and Methods: This retrospective study included 101 pediatric patients (age range; 1–18 years) diagnosed with Chiari 1 or Chiari 1.5 based on brain and cervical spine MRI findings between November 2022 and April 2025. Clinical and radiological data, including tonsillar descent, syringomyelia, craniovertebral junction anomalies, and basal angle measurements were analyzed. Twenty-one patients underwent posterior fossa decompression and postoperative MRIs were evaluated at 3 and 6 months. Statistical analyses were performed using chi-square, Mann–Whitney U, Wilcoxon signed-rank, and McNemar tests, with p <0.050 considered significant. Results: Among the 101 patients, 52 (51%) were female, and 49 (49%) were male (mean age; 11.1±4.9 years). Headache was significantly more frequent in operated patients (66.7% vs. 32.5%, p=0.014). Syringomyelia was also more common in the surgical group (33.3% vs. 3.8%, p <0.001), and tonsillar descent was greater (14.3±5.3 mm vs. 9.5±3.6 mm, p<0.001). No significant differences were found between the groups regarding age, sex, basal angle, or foramen magnum diameter. Postoperative follow-up revealed regression of syrinx dimensions and clinical improvement in all operated patients. Conclusion: Headache, syrinx formation, and greater tonsillar descent are key radiological and clinical predictors of surgical intervention in pediatric Chiari 1. While craniovertebral junction anomalies and hydrocephalus may coexist, they appear less predictive of surgical necessity. Posterior fossa decompression remains a safe and effective treatment in symptomatic pediatric patients, leading to both clinical and radiological improvement.

Purpose Idiopathic intracranial hypertension (IIH) in the pediatric population remains diagnostically challenging, particularly in the absence of papilledema, and increasingly depends on ancillary neuroimaging findings to support clinical assessment. The aim of this study was to systematically evaluate established magnetic resonance imaging (MRI) and magnetic resonance venography (MRV) markers of elevated intracranial pressure in children and to investigate oculomotor nerve cistern (OMC) distention as a potential novel adjunctive imaging biomarker of pediatric IIH. Methods This retrospective study included patients aged 0–18 years who underwent brain MRI and contrast-enhanced MRV for suspected intracranial hypertension and had cerebrospinal fluid (CSF) opening pressure measured by lumbar puncture. Patients with secondary causes of intracranial hypertension were excluded. MRI and MRV examinations were independently assessed by two blinded senior pediatric radiologists. Imaging parameters analyzed included pituitary gland height and superior contour, perioptic CSF distention with optic nerve sheath diameter (ONSD) measurements, optic nerve tortuosity, posterior globe flattening, Meckel’s cave dimensions, transverse sinus stenosis, jugular vein stenosis, and qualitative assessment of OMC distention. Patients were stratified according to CSF opening pressure, with values ≥28 cm H₂O considered elevated. Results Sixty-six patients met the inclusion criteria, of whom 44 demonstrated elevated CSF opening pressure. The mean ONSD was significantly greater in the elevated-pressure group compared with controls (5.60 ± 0.91 mm vs 5.04 ± 0.68 mm; p=0.012), and perioptic CSF distention exhibited the highest diagnostic sensitivity (90.9%). OMC distention was more frequently observed in patients with elevated CSF pressure (52.3% vs 27.3%), yielding moderate sensitivity (52.2%) and specificity (72.7%). Additionally, the anteroposterior diameter of Meckel’s cave was significantly increased in the elevated-pressure cohort. Conclusion Conventional MRI and MRV markers provide robust supportive evidence for the diagnosis of pediatric IIH. OMC distention appears to be a plausible adjunctive imaging biomarker that may enhance diagnostic confidence when interpreted in conjunction with established neuroimaging findings.

Background/Objectives: Mitral annular disorders constitute a heterogeneous group of structural abnormalities that can significantly influence morbidity and mortality in both adult and pediatric populations. Advances in cardiac magnetic resonance (CMR) imaging have refined the ability to characterize these disorders with high spatial resolution and reproducibility. Among them, mitral annular disjunction (MAD) and mitral valve prolapse (MVP) have emerged as interrelated entities implicated in valvular dysfunction, arrhythmogenesis, and myocardial remodeling. This study aimed to determine the prevalence of MAD in a pediatric cohort, explore its association with MVP, and delineate related CMR findings, including myocardial fibrosis. Methods: A retrospective review was conducted in 295 pediatric patients who underwent clinically indicated CMR between September 2022 and June 2025. Echocardiographic and CMR data were systematically compared for the detection of MAD, MVP, and mitral regurgitation (MR). MAD length and mitral annular measurements were obtained from two-chamber and left ventricular outflow tract (LVOT) cine sequences. Late gadolinium enhancement (LGE) was evaluated to identify myocardial fibrosis. Results: MAD was detected more frequently by means of CMR than echocardiography (23.2% vs. 9.3%), as was MVP (34.2% vs. 22.4%), whereas MR was more often observed on echocardiography (31.2% vs. 15.2%). Inter-modality agreement was moderate for MAD, moderate-to-substantial for MVP, and fair for MR. LGE was identified only in patients with concomitant MAD and MVP, suggesting limited myocardial involvement in isolated MAD. Conclusions: CMR demonstrates superior sensitivity in detecting MAD and MVP compared with echocardiography and allows for early recognition of systolic–diastolic annular dissociation before advanced myocardial remodeling occurs. These findings underscore the clinical utility of CMR as a complementary modality for comprehensive assessment, risk stratification, and follow-up of pediatric patients with suspected mitral annular abnormalities.