Tungsten Enteral Feeding Tubes and MRI Scans: Safety Information

Yes, tungsten-weighted enteral feeding tubes are MRI-safe (MR Conditional).

Why Tungsten?

• Non-ferromagnetic: Tungsten is paramagnetic (weakly attracted) but not ferromagnetic—it does not retain magnetization and experiences negligible torque/force in clinical MRI fields (1.5T, 3T).
• High density (19.3 g/cm³): Provides radiopacity for fluoroscopic placement confirmation and tube positioning without using ferromagnetic materials (e.g., stainless steel weights).
• Biocompatible: Encapsulated in medical-grade silicone/polyurethane; no direct tissue contact with tungsten.

MRI Safety Classification (per ASTM F2503):

• MR Conditional: Safe under specified conditions (e.g., ≤3T, specific SAR limits, tube secured).
• Manufacturers (e.g., Corpak, Avanos) provide MRI safety labeling with field-strength limits and conditions.

Clinical Practice:

• Always verify the specific product's MRI labeling before scanning.
• Inform the MRI technologist; they will confirm compatibility and may secure the tube.
• No need to remove tungsten-weighted tubes for MRI—unlike older stainless-steel-weighted tubes, which are MR Unsafe.

If unsure of the tube type, obtain a scout image or consult the manufacturer's IFU.