Pediatric Radiology最新文献

This report presents the prenatal imaging findings and short-term clinical outcome of a rare case of fetal cerebral sinovenous thrombosis, along with a brief review of the literature. A 31-year-old pregnant Afghan woman at 34 weeks of gestation (gravida 3, para 0, abortion 2) presented to the hospital with complaints of decreased fetal movement. Fetal cranial ultrasonography revealed a thick-walled, avascular, hypoechoic, mass-like lesion (17×18×18 mm) extending from the left foramen of Monro to the superior aspect of the thalamus and displacing the body of the left lateral ventricle. Fetal cranial magnetic resonance imaging (MRI) suggested subacute hemorrhage and demonstrated hyperintensity in the left transverse venous sinus, indicative of thrombosis. Serial follow-up revealed stability of the lesion; however, at 36 weeks, an emergency cesarean section was performed due to fetal distress. Postnatal cranial MRI and magnetic resonance venography (MRV) confirmed left transverse venous sinus thrombosis with subacute hemorrhage. The newborn received enoxaparin therapy for 3 months, remained clinically stable, and had no neurological deficits at the 4-month follow-up. Fetal intracranial hemorrhage has a broad differential diagnosis, and accurate identification of the underlying etiology is critical for prognosis and management. Fetal cerebral sinovenous thrombosis should be considered in the differential diagnosis when mass-like hemorrhagic lesions are detected on prenatal imaging. While short-term outcomes may be favorable in the absence of additional cranial pathology, the long-term prognosis remains uncertain.

Background: Photon-counting CT (PCCT) has the potential to improve diagnosis and reduce radiation exposure in pediatric congenital heart disease. Early data in pediatric patients has shown advantages of advanced post-processing techniques that are currently only available with high kilovolt (kV) protocols.

Objective: The purpose of our study was to compare image quality and radiation dose for low kV (70) and high kV (120) protocols in patients weighing under 10 kg.

Methods: In this IRB-approved retrospective review of ultra-high pitch cardiac CT scans in patients under 10 kg, we evaluated two protocols on a PCCT scanner: low kV (70) and high kV (120). Patient demographics, contrast-to-noise ratio in aorta and pulmonary artery, and subjective image quality scores using a 5-point Likert scale were evaluated by two readers in addition to radiation dose comparison.

Results: Fifty-eight scans were included, 28 in the 70 kV cohort and 30 in the 120 kV cohort. Median age was 0.17 years for 70 kV and 0.33 years for 120 kV and weight was 4.5 kg for 70 kV and 5.4 kg for 120 kV. Contrast-to-noise ratios (aorta 14.8 vs 17.8, P=0.6) and Likert scores for aorta (median 5 for both groups, P=0.2) were similar for both protocols. Radiation dose was significantly lower in the 70 kV group with CTDI of 0.13 mGy vs 0.25 mGy for 120 kV (P<0.001).

Conclusion: A 70 kV protocol shows promise for reducing radiation dose in infants with similar image quality compared to the 120 kV protocol, although advanced spectral reconstructions would not be available.

Background: Hemophagocytic lymphohistiocytosis is a non-malignant immune regulation disorder, with activation of uncontrolled inflammatory processes and multiorgan damage; primary hemophagocytic lymphohistiocytosis is genetic.

Objectives: To analyze clinical and brain magnetic resonance imaging features in children with familial hemophagocytic lymphohistiocytosis.

Materials and methods: This retrospective study included 28 children with molecularly confirmed hemophagocytic lymphohistiocytosis. Clinical and laboratory manifestations at initial presentation and upon reactivation were recorded. Routine brain magnetic resonance imaging scans were reviewed and severity scores were calculated for different molecular types.

Results: Eleven (39.4%) children presented with neurological symptoms, 13 (46.4%) with developmental delays, and four with altered levels of consciousness. Lesions predominated in white matter (39.3% subcortical, 35.7% periventricular, and 7.1% central), although 25% had gray matter involvement; 78.6% of the cases presented with cerebral volume loss. Brain stem, cerebellar, and meningeal involvement were observed in 14.3%, 25%, and 7.1%, respectively. The most common mutations were in UNC13D (53.6%), PRF (21.4%), RAB27A (17.9%), and STBXP2 (7.1%); of the children with these mutations, neurological symptoms were observed in 20%, 50%, 80%, and 50%, respectively. Central nervous system reactivation was more prevalent in patients with RAB27A mutations (60%). White matter changes were noted in 16.7% of PRF cases, predominantly involving central regions, whereas 80% of RAB27A cases exhibited periventricular white matter abnormalities. RAB27A mutations were associated with higher white matter severity scores, whereas UNC13D mutations had higher cerebral atrophy scores.

Conclusion: Variable imaging manifestations were observed in familial hemophagocytic lymphohistiocytosis, with white matter involvement predominating. Patients with RAB27A mutations had more frequent clinical and imaging-based neurological involvement.

We report a unique case of malignant transformation in a retinocytoma monitored using magnetic resonance imaging (MRI). This case is notable for a distinct drop in apparent diffusion coefficient (ADC) values that correlated with clinical transformation to retinoblastoma. This is the first report to highlight a change in ADC as a radiological marker of malignant conversion in retinocytoma. This finding suggests the potential role of ADC in prognostic assessment and risk stratification for patients with retinocytoma.

Background: Evidence for artificial intelligence (AI)-assisted paediatric fracture detection is limited. External validation and comparison of AI software are required before reliable use in clinical practice.

Objective: To evaluate and compare the performance of three commercially available AI software for detecting posttraumatic findings in paediatric patients.

Materials and methods: This retrospective study assessed three AI software using radiographs of children aged 2-17 years who presented to the emergency department after trauma. Radiographs of the lower leg, forearm, and elbow were included between January 2014 and January 2024 (lower leg), March 2022 and January 2024 (forearm), and July 2019 and January 2024 (elbow). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for fractures, effusions, and dislocations.

Results: A total of 3,013 patients with 3,414 radiographs were included: 1,074 lower leg (mean age 6.6 years), 1,142 forearm (7.4 years), and 1,198 elbow (7.5 years). All AI tools demonstrated high performance for lower leg and forearm radiographs, with sensitivity of 88.4-94.7%, specificity 93.6-99.2%, PPV 94.5-99.2%, and NPV 91.6-95.6%. In contrast, performance for elbow radiographs was reduced (sensitivity 72.8-91.6%, specificity 80.3-98.7%), with the lowest PPV of 86.1% and NPV of 79.5%. Sensitivity was notably reduced for specific paediatric fracture types, elbow effusions (posterior fat pad sign 40.6-82.3%), and dislocations (54.2-93.8%), with significant differences between AI software.

Conclusions: AI tools show promise for paediatric fracture detection, particularly in lower leg and forearm radiographs. Awareness of their limitations is essential for safe clinical use.

Abdominal compartment syndrome is a life-threatening condition caused by elevated intra-abdominal pressure, leading to impaired organ perfusion and dysfunction. In pediatric patients-especially neonates-diagnosis is challenging due to non-specific signs and limited clinical awareness. Pediatric abdominal compartment syndrome remains underrepresented in the literature, with few published cases and no standardized guidelines for diagnosis or management in this age group. We report the case of a premature newborn from a twin pregnancy who developed abdominal compartment syndrome following surgical repair of an omphalocele, emphasizing the value of ultrasound as an effective tool for the diagnosis and monitoring of abdominal compartment syndrome. This report contributes to the limited evidence available, highlighting the need for vigilance in similar high-risk scenarios, as early recognition and timely intervention are crucial to prevent irreversible damage.

Background: In vivo placental volume derived from magnetic resonance imaging (MRI) is a novel imaging tool to evaluate the placenta during pregnancy, as the placenta is difficult to access throughout gestation. There is a paucity of established standardized normative raw values and Z-scores for in vivo placental volume based on MRI.

Objective: To establish normative references for in vivo placental MRI-based volumes derived from a large cohort of healthy pregnant women carrying healthy fetuses throughout gestation.

Materials and methods: Healthy pregnant women with healthy singleton pregnancies greater than 16 weeks gestation were enrolled in a longitudinal, prospective observational study. In total, 313 placental MRIs were analyzed from 209 pregnant women. In-vivo placentas were manually segmented to derive volumes and Z-scores. Means, standard deviations, and percentiles for normative reference raw values were calculated using weekly gestational age (GA) bins. Placental volume Z-scores were calculated based on 2-week GA bins using means and standard deviations.

Results: Normative reference placental volumes from 209 subjects (313 scans) with median GA 31.43 [8.86] weeks are presented in weekly and bi-weekly GA bins. Using 2-week GA intervals, 95% of placental volume Z-scores were within ±2 standard deviations of the population mean.

Conclusion: This data provides established normative in vivo raw and Z-score values derived from placental MRI. The value of accessing the placenta in vivo through MRI has become increasingly recognized, as the importance of the placenta in fetal and postnatal health is now more widely known. Establishing normative reference values for the in vivo placenta throughout gestation benefits both the clinical and scientific communities.

Hydrocephalus is a frequently encountered neurological disorder of cerebrospinal fluid (CSF) physiology or dynamics, resulting in the abnormal enlargement of CSF spaces and often presenting with signs and symptoms of raised intracranial pressure. The etiology of hydrocephalus is numerous, regardless of the model used to understand its pathophysiology. Differentiating ventricular enlargement due to hydrocephalus or parenchymal atrophy can be difficult in pediatric patients, but certain imaging signs could help differentiate the two entities. The management of hydrocephalus aims to restore normal CSF dynamics, alleviate symptoms, and prevent long-term neurological complications with the help of ventricular drains and shunts. In this review, we will cover the updated pathophysiology, key etiologies, characteristic imaging findings of acute hydrocephalus and its complications, thus providing practical guidance for pediatric radiology fellows and radiologists in emergency settings.