Agency classClass IIOur severity:Severe FDA (Devices)·Z-1215-2017·Announced 2017-02-22

Siemens PRIMUS Radiation Therapy Systems Recalled for Collimator and Weld Defects

Siemens is recalling 194 PRIMUS radiation therapy systems due to incorrect collimator position displays and improper weld seams at the overhead suspension.

The agency’s classification

FDA (Devices): Class II

Class II is a situation in which use of or exposure to a violative product may cause temporary or medically reversible adverse health consequences, or where the probability of serious adverse health consequences is remote.

This is the agency’s own classification, taken from its notice. The severity score below is our assessment, not the agency’s. How recall classes work

What this means for you

Our assessment, not the agency’s: severity 4/5 (Severe).

The hazard poses a serious risk of illness, injury, or structural failure. Stop using the product immediately and contact the manufacturer for a refund or repair.

Our severity reasoning: The recall is classified as FDA Class II and involves a structural defect (improper weld seams) in a medical device used for cancer treatment, which meets the criteria for a Severe rating.

Plain-English summary

Siemens Medical Solutions USA, Inc. is recalling 194 PRIMUS Medical charged-particle radiation therapy systems. These systems are intended to deliver x-ray radiation for the therapeutic treatment of cancer. The recall involves specific model numbers 1940035 and 4504200, with a list of affected serial numbers provided in the official notice.

The recall was initiated because Siemens became aware of incorrect values for the rotational collimator position displayed on the systems. This issue is attributed to mechanical problems with the sensor slide. Additionally, the systems have improper weld seams at the overhead suspension.

The affected units were distributed in the United States. Healthcare facilities and users of these systems should contact Siemens Medical Solutions USA, Inc. for further instructions regarding the recall and necessary corrective actions.

The recalled product

Product: PRIMUS Medical charged-particle radiation therapy system Product Usage: The intended use of the SIEMENS branded PRIMUS family of linear accelerator systems is to deliver x-ray radiation for therapeutic treatment of cancer.
Manufacturer: Siemens Medical Solutions USA, Inc
Category: Medical Device — Radiation Therapy
Hazard: structural-defect
sensor-malfunction
Affected units: 194

Distribution

Distribution scope not specified by the agency.

Part of a larger recall action

This product is one of 4 recalled by Siemens Medical Solutions USA, Inc under a single FDA (Devices) recall action. The agency files each product separately, so the size of the action is not visible from this page alone.

See all 4 products in this recall →

Same manufacturer · Siemens Medical Solutions USA, Inc

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