Related Experiment Video
Updated: Jul 14, 2026
Role of Diffusion MRI Tractography in Endoscopic Endonasal Skull Base Surgery
Published on: July 5, 2021
Fungal versus bacterial brain abscesses: is diffusion-weighted MR imaging a useful tool in the differential
Christina Mueller-Mang1, Mauricio Castillo, Thomas G Mang
1Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
Introduction:
The aim of this study was to investigate the appearance of fungal brain abscesses on diffusion-weighted (DW) images, and to evaluate whether the imaging characteristics and apparent diffusion coefficient (ADC) values associated with fungal abscesses were distinct from those of bacterial abscesses.
Methods:
We retrospectively reviewed the MR images from nine patients with fungal brain infections, and 17 patients with pyogenic brain abscesses. All patients underwent conventional MR sequences and DW imaging on 1.5-T clinical MR scanners. ADC values of 20 fungal and 20 bacterial brain abscesses were calculated and compared using a random factor analysis of variance.
Results:
Multiple lesions were present in 6 of 9 patients (67%) with fungal abscesses and in 5 of 17 patients (29%) with bacterial abscesses. On DW images, all but one bacterial brain abscess showed a homogeneous high signal, whereas the appearance of fungal abscesses on DW images was more variable: in five of nine patients with fungal abscesses, the lesions were homogeneously hyperintense, while in the remaining four patients, the lesions were of mixed signal intensity. Mean ADC values were 0.74 x 10(-3) mm(2)/s in the fungal group and 0.486 x 10(-3) mm(2)/s in the bacterial group (P< or =0.05).
Conclusion:
Our results indicate that there is a trend towards higher ADC values in fungal lesions. Additional findings that support fungal rather than bacterial cerebral infection are multiplicity, signal heterogeneity on T2-weighted and DW imaging, and involvement of deep grey-matter nuclei.
Insights
Fungal brain abscesses show distinct diffusion-weighted (DW) imaging characteristics and higher apparent diffusion coefficient (ADC) values compared to bacterial abscesses. These findings aid in differentiating fungal from bacterial cerebral infections.
Area of Science:
- Radiology
- Neurology
- Infectious Diseases
Background:
- Distinguishing fungal from bacterial brain abscesses is crucial for effective treatment.
- Diffusion-weighted (DW) imaging and apparent diffusion coefficient (ADC) values offer potential biomarkers.
Purpose of the Study:
- To investigate the imaging appearance of fungal brain abscesses on DW images.
- To compare imaging characteristics and ADC values of fungal and bacterial brain abscesses.
Main Methods:
- Retrospective review of MR images from 9 fungal and 17 bacterial brain abscess cases.
- Conventional and DW imaging performed on 1.5-T scanners.
- Calculation and comparison of ADC values between fungal and bacterial abscess groups.
Main Results:
- Fungal abscesses more frequently presented as multiple lesions (67% vs 29%).
- DW imaging showed variable signal intensity in fungal abscesses (heterogeneous in 44%) versus homogeneous in bacterial abscesses (94%).
- Mean ADC values were significantly higher in fungal abscesses (0.74 x 10(-3) mm(2)/s) than bacterial abscesses (0.486 x 10(-3) mm(2)/s).
Conclusions:
- Higher ADC values suggest fungal etiology.
- Multiplicity and signal heterogeneity on T2-weighted and DW imaging support fungal brain infections.
- Involvement of deep grey-matter nuclei is another indicator of fungal cerebral infection.
Related Concept Videos
01:26Brain Abscess l: Introduction
01:26Differential Staining Technique
01:17Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this principle...
01:24Magnetic Resonance Imaging