# K173871: CalliSpheres Embolic Microspheres, 8Spheres Embolic Microspheres

- Pathway: 510(k) (Traditional)
- Applicant: Suzhou Hengrui Callisyn Biomedical Co., Ltd.
- Decided: Sep 17, 2018 after 271 days
- Product code: NAJ (Agents, Embolic, For Treatment Of Uterine Fibroids)
- Device class: 2
- Regulation: 21 CFR 870.3300
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 5 generations back to K961923 (1996). 8 ancestors in all.
3 later devices descend from it; 3 cite it directly.
0 of 12 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K150876: Bead Block, Biocompatibles UK, Ltd. (2016) Summary page 5.

## Most influential descendants
- K250209: Polyvinyl Alcohol Embolic Microspheres (2025), 0 descendants of its own
- K232934: Sunsphere (2024), 0 descendants of its own
- K210562: HRSpheres Narrow-Size Embolic Microspheres (2021), 0 descendants of its own

## Indications for use
Callispheres Embolic Microspheres and 8Spheres Embolic Microspheres are intended to be used for the embolization of arteriovenous malformations (AVMs) and hypervascular tumors, including uterine fibroids.

Source page: https://510kreport.com/device/K173871
Methodology: https://510kreport.com/methodology