FDA expands MRI labeling for InterStim SNM bladder and bowel control devices

The FDA has approved expanded MRI labeling for the InterStim II and InterStim Micro sacral neuromodulation (SNM) systems that use SureScan MRI leads. The devices are used to treat patients with bladder and bowel control conditions.¹

Howard Goldman, MD

Medtronic, the developer of the devices, reported in a press release that the updated MRI guidelines in the label expand the range of MRI scan parameters and allow a briefer waiting period between MRI scans.

"I'm pleased to see medical technology for SNM patients continue to improve," Howard Goldman, MD, professor and vice chairman of Quality and Patient Safety, Glickman Urological and Kidney Institute, Cleveland Clinic, stated in the press release.

"Optimal MRI labeling is an important enabler of greater access to therapy for patients and alleviates burdens on clinicians' practices," added Goldman.

These are the MRI labeling updates as described by Medtronic in the press release¹:

• For MRI scanning facilities with B1+rms technology, the new SureScan MRI lead scanning parameters increases B1+rms for 1.5 Tesla scans from 3.0 µT to 4.0 µT, and 3 Tesla scans from 1.3 µT to 2.0µT. B1+rms is the gold standard because it is consistent if a patient has multiple MRI scans across different facilities.
• The new Medtronic scanning parametersincreases SAR limits for 1.5 Tesla scans from 0.5 W/kg to 2.0 W/kg; and for 3 Tesla scans from 0.5 W/kg to 1.4 W/kg.
• The new labeling also decreases wait time from 60 minutes to 5 minutes for maximum duration scans (30 minutes).

Other recent InterStim developments

In August 2020, the FDA approved the InterStim Micro neurostimulator and InterStim SureScan MRI leads for the treatment of patients with bladder and bowl control conditions.²

InterStim Micro treats patients with overactive bladder, fecal incontinence, and non-obstructive urinary retention by delivering SNM therapy. In a news release at the time, Medtronic explained that SNM sends “electrical impulses to the sacral nerves located in the lower back to improve bladder and bowel control. Unlike oral medications that target the muscular component of bladder control, SNM offers control of symptoms through direct modulation of the nerve activity, normalizing the communication between the bladder and the brain.”

InterStim SureScan MRI leads enable full-body 1.5 and 3 Tesla MRI-conditional scans. They are used in conjunction with the InterStim Micro and the recharge-free InterStim II.

Also of note, Medtronic announced in October 2020 that the first patient had been implanted with the InterStim Micro neurostimulator in the ELITE study, which is examining the rechargeable SNS system in patients with overactive bladder.³ The study is examining the InterStim Micro in patients across all 4 symptoms for which the SNS device is indicated: urinary urge incontinence, urinary frequency, non-obstructive urinary retention, and fecal incontinence.

References

1. Medtronic Receives FDA Approval for Expanded MRI Labeling of InterStim™ SureScan™ MRI Leads. Posted online February 18, 2021. Accessed February 18, 2021. https://prn.to/2Zrl6ML.

2. Medtronic Expands Leadership in Treating Bladder and Bowel Control Conditions with Two New FDA-Approved Products: InterStim™ Micro Neurostimulator and InterStim™ SureScan™ MRI Leads. Published August 3, 2020. https://bit.ly/2PsC1d7. Accessed February 18, 2021.

3. Medtronic Announces First Patient Implanted in ELITE Study of InterStim™ Micro. Posted October 6, 2020. Accessed February 18, 2021. https://prn.to/2F4ygZA.