gms | German Medical Science

Objective: Brain abscesses (BA) are rare intracerebral lesions. However, surgical removal or puncture of BA is frequently considered due to the space-occupying effect and/or for diminishing the cerebral infectious focus. However, meticulous identification of a premature capsule or inflammatory tissue can be challenging. As most BA are accompanied by disruption of the blood brain barrier (BBB), thus, intensely depicted by Gadolinium-enhanced magnetic resonance imaging (MRI), we sought to evaluate the efficacy of 10% Fluorescein Sodium (FL, ALCON, Germany) in combination with the YELLOW 560 nm filter of the PENTERO 900 surgical microscope (ZEISS Meditec, Germany) for improved visualization of BA in small retrospective series.

Methods: Seven consecutive patients (3 men, 4 women; mean age 53.8 years) with intracranial BA were included. In all cases, the diagnoses were confirmed microbiologically. All of the patients gave written informed consent at least on the day before craniotomy as the administration of FL in neurosurgery still is off-label. 5 mg/kg bodyweight of FL were injected during induction of anesthesia via the central venous line. In all cases, the PENTERO 900 surgical microscope, equipped with the YELLOW 560 nm filter was used while approaching the lesion and during removal of the capsule and the pus.

Results: In all cases brilliant visualization and intense fluorescence of the BA capsules were achieved under the filtered light. However, the pus was never enhanced by FL. We encountered no adverse events or allergic reactions due to the administration of FL.

Conclusion: To the best of our knowledge, this is the first report about the use of fluorescence-guided resection of BA. Under the dedicated YELLOW 560 nm filter, FL broadly visualizes BA. This can be helpful in approaching and resecting contrast-enhancing inflammatory cerebral lesions.