Air-jet Pneumodissection in Neuroanatomy: a new method for the study of White Matter anatomy in the Human Brain.

Traditional white matter (WM) dissection techniques, such as the Klingler method, employ wooden or metal instruments that may cause myelin wear and limit fine anatomical separation. Inspired by clinical water-jet applications, we investigated the feasibility of an air-jet dissector (pneumodissection) for WM dissection, leveraging the Coandă effect to gently separate contiguous fiber tracts while preserving their integrity. A portable air compressor was modified with an extended tube and an 18G blunt needle tip. A left cerebral hemisphere, prepared according to a modified Klingler freeze-thaw protocol, was dissected under exoscope magnification. Airflow was delivered at pressures between 0.8 and 3 bar. Dissection followed Klingler's stepwise protocol, adapted to the ergonomics and dynamics of the air-jet device. The air-jet dissector enabled progressive detachment of pia-arachnoid membranes, cortex and U-fibers, with clear exposure of commissural, projection, and association bundles. Low-pressure flow (0.8-1.2 bar) was used for delicate superficial planes and U-shaped fibers, whereas transient increases up to 3 bar were used for more resistant cortical or deep tissue planes. During this feasibility experiment, the air jet reduced broad direct instrument-tissue contact and helped clear loose debris and surface fluid from the operative field. Vessel-fiber interfaces and anatomical cleavage planes were sharply delineated. The device's portability and pressure modulation allowed both blunt and sharp dissection functions through a single tool. Air-jet dissection is a novel and complementary technique for white matter study. The present study does not establish superiority or reduced tissue damage compared with conventional manual tools because no matched quantitative comparison or histological assessment was performed. Further replicated and standardized studies are required to define reproducibility, tissue effects, and any objective advantage over established dissection methods.