Cesium-131 Strands contain seeds and bio-absorbable spacers placed end to end within a bio-absorbable sleeve. The seeds and spacers are sealed within the sleeve, allowing the strand to be implanted as a unit.

This technique significantly reduces the potential for individual seed migration and also accommodates extracapsular extension dose coverage when planned appropriately.


Good for Prostate procedures


  • Significantly reduces seed migration
  • Linking, bio-absorbable sleeve
  • Bioabsorbable spacer
  • Bioabsorbable sleeve dissolves after implant
cesium 131 product: strand tray
cesium 131 product: strands


Strands are shipped individually via Strand Tray and ready for implantation.

Perspective Therapeutics Difference

  • Expert Sales and Support teams ensuring real-time ordering and delivery for procedures throughout the body.
  • Committed to offering interactive training programs throughout the US teaching the leading techniques and the newest tools.
  • Empowering patients to make their own treatment decisions based on decades of data.
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Your Isotope Choice Makes a Difference

Not all brachytherapy radioisotopes are the same. Compared to alternative brachytherapy seeds, Cesium-131 offers the highest energy and shortest half-life.

Isotope Introduced Half life Kev Delivery rate Detectable in the body
Iodine-125 1965 60 Day 20.8 204 Days for 90% Dose 600 Days
Palladium-103 1987 17 Day 28.5 58 Days for 90% Dose 170 Days
Cesium-131 2004 9.7 Day 30.4 33 Days for 90% Dose 97 Days


1. Frank SJ, et al. American College of Radiology Appropriateness Criteria: Permanent Source Brachytherapy for Prostate Cancer. Brachytherapy. 2011:10(5):357-362
2. Cesium-131 Instructions for Use

United States Brief Statement

Cesium-131 brachytherapy seeds are indicated for the treatment of malignant disease(e.g., head and neck, eye, brain, breast, prostate, etc.) and may be used in surface, interstitial, and intra cavitary applications for tumors with known radio sensitivity. The seeds may be used as a primary treatment or in conjunction with other treatment modalities, such as external beam radiation therapy, chemotherapy or as treatment for residual disease after excision of primary tumors. Contraindications: As with other brachytherapy sources, treatment of tumors in generally poor condition (e.g. ulcerated) is not recommended with Cesium-131 brachytherapy seeds due to the potential for source migration. Prior to use, please reference the Cesium-131 Instructions for more information on indications, contraindications, warnings, all precautions, and adverse events.

Caution: Federal law restricts this device to sale by or on the order of a physician.