Table 4.

Microfluidic injury models: applications, advantages, and limitations

Injury Model	Applications and Examples	Advantages	Limitations
Vacuum-assisted Injury	Simple method of applying axotomy or neuronal injury in vitro.	Simple to perform Versatile No special equipment required Widely utilized	Calibration needed for each individual setup Axotomy may be inappropriate model for most CNS injuries
Chemical Injury	Mimic variety of biochemical microenvironments in injury or diseases: Excitotoxicity Hemolytic Injury Immunotoxicity	Simple to perform Fluidic isolation can be precisely applied to specific subcellular regions Versatile	Does not recapitulated physical aspects of injury Amount of precision may require more complicated microfluidic devices Requires precise fluid level maintenance
Physical Injury	Simulate variety of physical aspects of injury to specific cellular regions: Stretch/Strain Injury Compression Injury	Reliably reproduces range of physical injury Can specifically isolate injury to axonal or somal regions of neurons	May require bulky pneumatic actuation Device may require complex fabrication processes Complex calibration of injury
Laser-based injury	Precise axotomy of individual axons in a variety of model systems: In vitro rodent neurons In vivo C. Elegans In vivo Drosophila	Extremely precise injury to a single axon In vitro and in vivo injury Amenable to high throughput screening In vivo injury does not require anesthetics	Requires complex and expensive optical components Single axon axotomy may not be representative of most CNS injuries