MAUDE Adverse Event Report: MEDTRONIC NEUROMODULATION KINETRA; IMPLANTED SUBCORTICAL ELECTRICAL STIMULATOR (M

Model Number 7428

Device Problems Impedance Problem (2950); Patient Device Interaction Problem (4001)

Patient Problems Visual Disturbances (2140); Shaking/Tremors (2515); Sleep Dysfunction (2517)

Event Date 12/24/2021

Event Type  Injury  

Event Description

Abstract/summary: cervical dystonia (cd) is the most common adult-onset focal dystonia.Non-motor symptoms, such as insomnia, can greatly impact the quality of life in cd patients.Cd can be treated with deep brain stimulation (dbs) of the globus pallidus pars interna (gpi) although its effect on sleep is not yet fully understood.Here, we report a case of a (b)(6) year old female patient with cervical dystonia, who developed an unusual form of insomnia following her dbs surgery.Our patient reported recurrent episodes of visual symptoms (flashing lights), which would often wake her up at night.Following surgical revision of the extension wire, these visual symptoms completely resolved.This case provides an example of impedance oscillations caused by pressure on the pillow, which resulted in irregular delivery of current (according to ohm's law) and recruitment of optic tract fibers secondary to excessive current.Reported event: 1 a (b)(6) year old women with 38 year history of cervical dystonia was initially treated with conventional oral medications and regular cycles of botox injections.The patient subsequently underwent bilateral gpi dbs surgery.Post-op impedance check did not reveal any abnormal values and the patient's toronto western spasmodic torticollis rating scale (twstrs) score was 23, which improved to 16 by the end of their programming period (11 months later).The final stimulation settings were: 1e2þ/1.8 v/120 ms/180 hz; and 6- caseþ/1.7 v/120 ms/180 hz, in the right and left gpi, respectively.Despite the lower twstrs score, the patient's quality of life had declined following the development of an unusual form of insomnia.The patient experienced recurrent episodes of visual symptoms that would repeatedly wake them up in the middle of the night. the patient described seeing flashing lights as if someone was shining a torch at their face, akin to a lighthouse.The patient would only experience these visual symptoms when lying down on their right side.These episodes were also accompanied by a transient worsening of head tremor.The examination confirmed good control of the cervical dystonia with no history of visual symptoms during the day and normal impedances.During one of the initial programming sessions, it was documented that the patient experienced visual flashes when the stimulation setting was: 3- caseþ/3.1 v/120 ms/180 hz or 6- caseþ/2.5 v/90 ms/180 hz; therefore, the possibility of fluctuating impedances was suspected.Similar symptoms were reproduced when gentle pressure was applied behind the right ear, where the connector between the intracranial leads and the extension wire to the ins were situated.This was also most likely taking place when the patient was resting their head on the pillow at night.A faulty or damaged connector was suspected; however, a plain radiograph of the skull did not demonstrate any obvious abnormality.Based on their previous experience in patients with fluctuating impedances, the patient's ins was replaced.This led to a deterioration in cervical dystonia symptom control, however there was an almost complete resolution of the visual symptoms as well as insomnia.Ten years following the initial dbs surgery, the patient subsequently underwent another ins revision along with extension wire replacement.They used the previous voltage-constant setting, and the cervical dystonia significantly improved with no further occurrence of the visual symptoms and insomnia.The following device specifics were provided: ins model - kinetra, lead model - 3387, and ins model - activa pc.

Manufacturer Narrative

Please note that this date is based off of the date that the article was accepted for publication as the event date was not provided in the published literature.It was not possible to ascertain specific device information from the article or to match the events reported with previously reported events.Correspondence has been sent to the author of the article inquiring about individual patient information and additional information regarding the reported events.Please note that this device was used in an off-label manner as it was implanted for dystonia.Information references the main component of the system.Other relevant device(s) are: product id: 3387, serial/lot #: unknown, ubd: , udi#: ; product id: neu_unknown_ext, serial/lot #: unknown, ubd: , udi#: if information is provided in the future, a supplemental report will be issued.

• Brand Name: KINETRA
• Type of Device: IMPLANTED SUBCORTICAL ELECTRICAL STIMULATOR (M
• Manufacturer (Section D): MEDTRONIC NEUROMODULATION; 7000 central ave ne; minneapolis MN 55432
• Manufacturer (Section G): MEDTRONIC NEUROMODULATION; 7000 central ave ne; minneapolis MN 55432
• Manufacturer Contact: glen belmer ; 7000 central avenue ne rcw215; minneapolis, MN 55432 ; 6122713209
• MDR Report Key: 13647061
• MDR Text Key: 289773066
• Report Number: 2182207-2022-00352
• Device Sequence Number: 1
• Product Code: MRU
• Combination Product (y/n): N
• Reporter Country Code: CA
• PMA/PMN Number: H020007
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Foreign,Literature,Health Professional
• Reporter Occupation: Other
• Type of Report: Initial
• Report Date: 03/02/2022

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 03/02/2022
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: 7428
• Device Catalogue Number: 7428
• Was Device Available for Evaluation?: No
• Date Manufacturer Received: 02/01/2022
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1
• Patient Outcome(s): Required Intervention
• Patient Age: 66 YR
• Patient Sex: Female