Advanced fluorescence techniques in white matter fiber visualization for neurosurgical training

Abstract

Background: Neurosurgical training requires a deep understanding of brain anatomy, especially white matter fiber pathways, to enhance surgical precision. Traditional dissection techniques, such as Klingler's white matter dissection, are essential, but newer methods can provide additional clarity. This study explores the application of a fluorescent-assisted technique to improve the visualization and understanding of white matter fibers during neurosurgical training.

Methods: Twelve human brains were dissected following Klingler's protocol, with a focus white matter fiber pathway. Fluorescent alcoholic and oily solutions were applied to highlight the fibers. Ultraviolet (UV) blacklight and yellow monochromatic filters were used to enhance visualization. Dissections were documented through photography, and the effectiveness of the fluorescent techniques was analyzed.

Results: The application of UV light and fluorescent solutions enhanced the visualization of fiber pathways, particularly in regions with irregular fibers, such as the sagittal stratum. The alcoholic solution flowed along the anatomical paths of the fibers, aiding in their differentiation. The oily solution proved effective in specific areas, such as the internal capsule. The use of fluorescent techniques allowed for improved identification and anatomical detailing of major white matter tracts.

Conclusion: The fluorescent-assisted dissection technique significantly enhances the visualization of white matter fibers, offering a valuable tool for neurosurgical training. This method deepens anatomical understanding, provides a three-dimensional perspective of brain structures, and can improve surgical outcomes. The study suggests potential applications in other fields, such as glioma simulation and bypass patency testing.

Keywords: Fluorescent technique; Neurosurgery; Neurosurgical training; White matter fibers.

Figure 1:

Fluorescent alcoholic solutions.

Figure 2:

Fluorescent oily solutions.

Figure 3:

(a) A yellow monochromatic glass filter utilized as a lens for capturing images. (b) Yellow monochromatic glasses were used in the workstation while applying fluorescent solution under the neon black ultraviolet light.

Figure 4:

A forty-watt neon black ultraviolet light. (a) In the off mode, do not emit light. (b) On mode, emitting light.

Figure 5:

(a and b) Lateral cerebral surface dissections were performed following the application of black ultraviolet (UV) light, revealing distinctive contrasts in prefilter and postfilter images, respectively. (c and d) Axial cross-sectional analysis of the brain was conducted. The left hemisphere of this specimen underwent dissection in the preceding week, while the right hemisphere was resected during the photographic session. It is noteworthy that the heightened prominence of black UV light contrast correlates with the timing of the specimen dissection, thereby enhancing the efficacy of the anatomical study.

Figure 6:

(a) Hemispheric white matter dissection using the alcoholic fluorescent solution. The lateral surface of the brain reveals fluorescent blue-colored fibers of the stratum sagittale in the antero-posterior orientation and fibers of the corticomedullary tract in the supero-inferior orientation. Notably, the contrast highlights the clear and comprehensible delineation of pathways between the fluorescing fibers and those devoid of fluorescence. (b) Dissected lateral brain surface using oily fluorescent solution unveils white matter fibers, featuring short association u-shaped fibers in fluorescent red, a segment of the arcuate fasciculus in fluorescent green, and a segment of the inferior fronto-occipital fasciculus in fluorescent blue. (c) A specifically delineated segment of the arcuate fasciculus is highlighted in yellow ink. (d) Dissection of the right hemisphere displays the anterior commissure, distinguished by a light red coloration.

Figure 7:

Lateral white fiber dissection aimed at exposing the superior longitudinal fasciculus, inferior fronto-orbital fasciculus, and uncinate fasciculus. (a) Cross-section image with application of fluorescent solutions but without filters or ultraviolet (UV) light. (b) Shows an image with the application of an alcoholic solution using a gravity-guided technique under only UV light effect. (c) A yellow monochromatic filter is employed to optimize colors and highlight the white fiber tracts.

Figure 8:

The application of fluorescent light emitted by the neurosurgical microscope during the neurosurgical approach of a high-grade glioma. The image does not reveal the internal microscope’s fluorescent light filter, as it is integrated and not visible in this particular view.