CT and MRI Findings in Cerebral Aspergilloma

Abstract

ZUSAMMENFASSUNG Ziel Zerebrale Aspergillose betrifft meist immunsupprimiertePatienten und weist aufgrund der oftmals unspezifischen Klinik ein hohes Morbiditäts-und Mortalitätsrisiko auf. Eine frühe Diagnosestellung ermöglicht die effektivere Einleitung der Therapiemaßnahmen und die Verbesserung des Outcome.Material und Methoden Die CT-und MRT-Aufnahmen von neun Patienten aus zwei Zentren wurden ausgewertet. Die Diagnose der zerebralen Aspergillose wurde mittels Biopsie und histopathologischer Begutachtung verifiziert. Die MRT wurde an 1,5T-und 3T-Geräten durchgeführt, die Untersuchungsprotokolle enthielten jeweils DWI, T2-und T1-gewichtete Bilder mit und ohne Kontrastmittel.Ergebnisse In der CT wiesen die Aspergillome kein typisches Erscheinungsbild auf. In der MRT waren die Aspergillome zu 100 % randständig diffusionsgestört (9/9). Mehrere hypointense Schichten in der Aspergilluswand, insbesondere an der Innenseite, waren typisch in den Aufnahmen mit T2-Wichtung (100 %, 9/9). Die Aspergillome waren sowohl T1-hypointens (66 %, 6/9), sowie in 33 % anteilig T1-hyperintens (3/9). In 78 % (7/9) der Fälle fand sich ein randständiges Enhancement nach Gadoliniumapplikation.Schlussfolgerung Aspergillome weisen typischerweise eine kräftige, ringförmige Diffusionsrestriktion auf (9/9). Typische Befunde in Aufnahmen der T2-gewichteten Bilder sind zwiebelschalenartig angeordnete hypointense Schichten, die innere Zone der Aspergilluswand ist aufgrund paramagnetischer Effekte besonders signalarm (9/9). Der Großteil der Aspergillome weist nach Kontrastmittelapplikation ein ringförmiges Enhancement auf (7/9). ABSTR AC TPurpose Invasive aspergillosis usually affects immunocompromised patients. It carries a high risk of morbidity and mortality and usually has a nonspecific clinical presentation. Early diagnosis is essential in order to start effective treatment and improve clinical outcome. Materials and MethodsIn a retrospective search of the PACS databases from two medical centers, we identified 9 patients with histologically proven cerebral aspergilloma. We systematically analyzed CT and MRI imaging findings to identify typical imaging appearances of cerebral aspergilloma.Results CT did not show a typical appearance of the aspergillomas. In 100 % (9/9) there was a rim-attenuated diffusion restriction on MRI imaging. Multiple hypointense layers in the aspergillus wall, especially on the internal side, were detected in 100 % on T2-weighted imaging (9/9). Aspergillomas were T1-hypointense in 66 % of cases (6/9) and partly T1-hyperintense in 33 % (3/9). In 78 % (7/9) of cases, a rim-attenuated diffusion restriction was detected after contrast agent application.Conclusion Nine cases were identified. Whereas CT features were less typical, we observed the following imaging features on MRI: A strong, rim-attenuated diffusion restriction (9/9); onion layer-like hypointense zones, in particular in the innermost part of the abscess wall on T2-weighted images (9/9). Enhancement of the lesion border was present in the majority of the cas...

Diversity and Surgical Management of Intracranial Fungal Infections

“…MRI-T2 images can present hypointense or hyperintense, as well as cystic lesions with hypodense periphery and hyperdense center. The typical pattern on MRI-T1 was isointense/hypointense imaging with peripheral rim of hyperintensity and internal heterogeneous contrast enhancement, this phenomenon has also been reported in previous literature 17 . A single-center retrospective study showed that cryptococcal infection may present a hypointense lesion on the T2 image with a peripheral hyperintense edema shadow.…”

“…Although imaging can help with the diagnosis to some extent, the manifestations can vary depending on the pathogen, the immune status of the body and the age of the lesions 2,16,17 . In our patients, even with the same MRI sequence, the fungal infections manifested to different extents.…”

“…The typical pattern on MRI-T1 was isointense/hypointense imaging with peripheral rim of hyperintensity and internal heterogeneous contrast enhancement, this phenomenon has also been reported in previous literature. 17 A single-center retrospective study showed that cryptococcal infection may present a hypointense lesion on the T2 image with a peripheral hyperintense edema shadow. Aspergillus showed isointense lesions, and the enhanced image of Cryptococcus superior was stronger than Aspergillus.…”

Aspergillus fumigatus cerebral abscess following hemodialysis: A case report

“…Neuroimaging techniques, such as contrast CT scan or MRI are important diagnostic toolsforthe identification of brain abscesses that help to differentiate a fungal cerebral abscess from a bacterial abscess. A fungal cerebral abscess presents with a typical finding of a hypodense lesion with a contrast-enhancing ring in a CT scan or MRI scan [ 8 ]. Unlike bacterial abscesses, which are usually solitary lesions, fungal abscesses are more likely to be numerous.…”