Radiologie (Heidelberg, Germany)最新文献

Clinical/methodological issue: Pediatric sarcomas representing a rare, heterogenous group of highly malignant tumors. Due to their aggressiveness and complex anatomy during growth, precise imaging is essential for prognosis.

Standard radiologic methods: Magnetic resonance imaging (MRI), using specific pediatric protocols (small field of view [FOV], thin slices), is the gold standard for local staging. Ultrasound is pivotal for primary diagnosis and biopsy planning, while low-dose chest computed tomography (CT) is used to assess pulmonary metastases.

Methodological innovations: Diffusion-weighted MRI and positron-emission tomography (PET)/MRI represents a low-radiation and highly efficient alternative to PET/CT for whole-body staging, especially for long-term aftercare.

Performance: Imaging enables precise delineation of neurovascular structures and growth plates, forming the basis for limb-sparing surgical procedures. However, differentiating between vital residual tumor, recurrence, and posttherapeutic changes (scars, edema) remains challenging.

Achievements: The consistent application of standardized study protocols and the interdisciplinary integration of radiology, oncology, and surgery are crucial for the success of modern therapeutic concepts.

Primary malignant bone tumours are rare (about 0.2% of all malignancies) whereby-according to age-both osteosarcoma and Ewing's sarcoma are the most frequent bone sarcomas in children and adolescents. Both sarcomas are highly-malignant tumours with poor prognosis (Ewing's sarcoma) in particular when metastasized (osteosarcoma). There is a broad diagnostic armamentarium available, allowing precise detection of such tumours. However, alertness and familiarity of (early) radiological signs (such as periosteal reactions) are prerequisites to arouse suspicion. Radiological methods (plain radiography, magnetic resonance imaging [MRI], computed tomography [CT], ultrasonography) will be discussed regarding their pathomorphological clues. Likewise, both use and significance of more advanced imaging modalities (dual-energy CT, photon-counting CT; the Dixon technique and MRI with ultrashort time-to-echo [TE] sequences) are reviewed.

Despite its advantages, the application of magnetic resonance imaging (MRI) involves specific safety risks, primarily caused by the strong static magnetic field and the alternating electromagnetic fields, in particular the high-frequency (HF) and gradient fields, posing hazards to both patients and medical personnel. Particularly problematic are ferromagnetic objects that can enter the magnetic field uncontrolled, potentially causing severe injuries. Additionally, metal implants can interact undesirably with the MRI system, leading to tissue heating or malfunctioning. The gradient fields required for spatial encoding can cause unwanted nerve stimulations. The HF fields can cause electrically conductive materials to overheat, potentially resulting in burns; however, appropriate safety measures, such as labeling, specialized safety training and the automatic monitoring of critical safety parameters can extensively minimize these risks.

Sarcomas are malignant tumors of connective and supporting tissues characterized by substantial biological and clinical heterogeneity. Their optimal treatment requires specialized expertise, particularly in radiological diagnostics. The correct interpretation of imaging procedures represents the first crucial step in treatment planning. Radiologists play a key role by recognizing suspicious findings and initiating early referral to specialized sarcoma centers. Depending on the histological subtype, sarcomas require tailored imaging strategies. A notable example is whole-body magnetic resonance imaging (MRI) for the detection of osseous metastases in myxoid liposarcoma. The assessment of treatment response in the neoadjuvant setting also poses a particular challenge as it is not uncommon for treatment-related imaging changes to mimic tumor progression (pseudoprogression) and must be reliably distinguished from true progression. During follow-up an appropriate balance between oncologic safety, such as early detection of local recurrence or metastases, and minimizing cumulative radiation exposure must be achieved.

Objective: The aim of the current study was to describe neuroimaging findings of Epstein-Barr virus (EBV)-associated primary central nervous system lymphoproliferative disorder (PCNS-LPD) in human immunodeficiency virus (HIV)-positive individuals.

Methods: The clinical data of four HIV-positive patients with confirmed EBV-associated PCNS-LPD were retrospectively analyzed from November 2018 to August 2024. All patients had undergone magnetic resonance imaging (MRI) examinations. The location, signal intensity, and enhancement pattern of the lesions on MRI were retrospectively evaluated.

Results: The pathological diagnosis of EBV-associated PCNS-LPD was made in all four patients, in two cases by surgery and in two by biopsy. All four patients presented with limb motor dysfunction, and three had dizziness or headache. On MRI, lesions were located in the periventricular white matter in three patients; they involved the left cerebral peduncle and basal ganglia in two patients, the medulla oblongata in two patients, the right cerebellar peduncle and splenium of the corpus callosum in one patient, and the cortex and subcortex in one patient. All lesions showed hypointense to isointense signal intensity (SI) on T1-weighted imaging and isointense to hyperintense SI on T2-weighted imaging, as well as exhibiting restricted diffusion in the peripheral portions of the lesions. All lesions showed either ring-like or nodular inhomogeneous enhancement.

Conclusion: In patients with HIV/acquired immune deficiency syndrome (AIDS) and EBV infection, multiple lesions in the periventricular regions and other intracranial sites should raise suspicion for EBV-associated PCNS-LPD. Although imaging findings may provide some evidence of EBV-associated PCNS-LPD, a differential diagnosis remains necessary.

Purpose: Susceptibility-weighted imaging (SWI) has emerged as a valuable tool in the evaluation of acute ischemic stroke. This study aimed to assess the correlation between the susceptibility vessel sign (SVS) and the National Institutes of Health Stroke Scale (NIHSS) scores, and as well as to explore the association between the grade of the prominent vessel sign (PVS) and clinical outcomes.

Methods: The study population comprised consecutive patients with ischemic stroke evaluated at our institution over a 6-month period. A total of 124 patients (82 with anterior and 42 with posterior circulation stroke) were evaluated for the presence of the SVS and for thrombus length on SWI. Patients with anterior circulation stroke were further classified according to the grade of PVS. Admission and discharge NIHSS scores were also recorded. Associations between SWI findings, NIHSS scores, and treatment modality were assessed using correlation and group comparison analyses.

Results: The mean age of the patients was 71.5 ± 13.8 years (range: 23-100). Patients with SVS had significantly higher admission NIHSS scores (p = 0.041), and SVS was more frequently observed in those with prominent veins (p < 0.001). The PVS grade correlated with both admission and discharge NIHSS scores (p = 0.005 and p < 0.001, respectively). Patients with higher PVS grades showed less improvement in NIHSS scores. Endovascular treatment was associated with a significantly greater reduction in NIHSS scores in the overall study population (p = 0.019).

Conclusion: Susceptibility-weighted imaging provides essential information in acute ischemic stroke, with assessment of SVS presence and PVS grading serving as imaging biomarkers predicting clinical severity.

The use of multimodal data is essential for the precise diagnosis and treatment of brain tumors. In this context, multimodal data encompass multisequence magnetic resonance imaging, computed tomography, positron emission tomography, histopathological images, molecular and genomic profiles, structured clinical variables, and radiological reports. With the rapid advancement of artificial intelligence, integrating these heterogeneous data sources has become a central research direction for improving diagnostic accuracy, prognostic assessment, and therapeutic decision-making in neuro-oncology. However, substantial discrepancies exist across data modalities in terms of spatial resolution, semantic representation, and measurement scales, posing significant challenges for effective cross-modal integration. Multimodal large language models (MLLMs) enhance both interpretative and generative capabilities by jointly modeling visual, textual, and structured data, thereby offering a unified framework for addressing these challenges in brain tumor analysis. This review provides a comprehensive overview of MLLMs, covering their methodological foundations, representation learning strategies, and cross-modal alignment mechanisms. We further summarize their applications in both research and emerging clinical settings, including diagnosis support, prognosis prediction, treatment planning assistance, and radiology report generation. Finally, we discuss current limitations, such as data scarcity, interpretability constraints, and clinical deployment barriers, and outline future directions toward robust, explainable, and clinically translatable MLLM systems in neuro-oncology.

Background: Trinucleotide disorders are a heterogeneous group that lead to neurodegeneration with severe motor and psychiatric impairments. Neither the clinical presentation nor the radiological signs are specific, leading to frequent misdiagnoses.

Objectives: Neuroradiological signs in trinucleotide disorders.

Methods: A search in pubmed.gov was conducted to identify studies reflecting the current state of knowledge.

Results: An overview of the most common trinucleotide disorders and their characteristic radiological features is provided.

Conclusion: As in many degenerative diseases, imaging represents only one piece of the puzzle and primarily provides guidance as to the diagnostic direction.