Quantum filament

From Memory Alpha, the free Star Trek reference.

A quantum filament is a type of spatial anomaly.

Although quantum filaments can be hundreds of meters long, they are very difficult to detect because they have almost no mass. If a filament came into direct contact with a starship, it would cause severe systems damage. Only when a filament was in close proximity of a ship could the on-board sensors detect it because of its subspace distortions and high-energy particles.

The USS Enterprise-D ran into several quantum filaments in 2368 (stardate 45156.1) and suffered a major power loss. Several crewmembers were killed or injured and with the emergency bulkheads closed due to the isolation protocol, they were trapped in various parts of the ship. The Enterprise was also in danger of losing antimatter containment, but the crew managed to restore power before this could occur. (TNG: "Disaster")