eCoin — Implantable Tibial Nerve Stimulator
eCoin (Valencia Technologies, now part of Boston Scientific) is a leadless tibial neurostimulator powered by a non-rechargeable battery. US labeling covers urgency urinary incontinence (UUI) after intolerance of or inadequate response to conservative treatments, or after a successful percutaneous tibial nerve stimulation (PTNS) trial.[1]
Design and Patient Tasks
The nickel-sized, coin-shaped device is implanted subcutaneously above the lower-leg fascia, over the posterior tibial nerve. The feasibility study described a 20-minute procedure under local anesthesia.[2][3] It supplies programmed, automatic, low-duty-cycle intermittent stimulation rather than continuous therapy. Treatment begins after wound healing, and the feasibility protocol activated the implant at about four weeks. Clinicians can adjust stimulation amplitude.[3][4][1] The patient manual describes 30-minute sessions every 3 days for the first 18 weeks and every 4 days afterward, on the left or right leg near the ankle, with same-day discharge.[8] It states that, if eCoin works well for a patient, symptom improvement may take up to about 8 weeks after activation.[8]
The patient does not wear an external power unit or attend recurring treatment sessions. The patient controller magnet stops unwanted stimulation, and the patient must be able to use it as instructed. Battery life depends on settings, and depletion requires device replacement. The US patient manual gives 3 to 5 years at the nominal 6 mA setting and about 1 year at the 15 mA device maximum, although another section of the same manual states 1 to 8 years. The clinician is notified 6 months before the projected end of service life, and the manual notes that scar tissue may prevent a new device from being placed in the same pocket.[8] Wound follow-up, programming and eventual replacement are part of counseling.[1]
Mechanism
eCoin delivers tibial nerve stimulation. Tibial afferents share sacral spinal segments with the bladder and pelvic-floor innervation, and afferent modulation is the proposed basis for reduced urgency and detrusor overactivity. The practical difference from office-based PTNS is automatic delivery without the weekly office sessions used for induction and the maintenance sessions that follow.
Clinical Evidence
The published studies were open-label and single arm.
| Study | Population and result | Interpretation |
|---|---|---|
| Feasibility trial | 46 participants; at 3 months, 32 of 46 (69.6%) had at least 50% UUI reduction (median daily episodes 4.2 to 1.7), with more than 20% dry at 3 and 6 months | 98% women, mean age 63.4 years; no sham or active comparator [2] |
| Feasibility, 12 months | 65% responders and 26% completely continent | Same 46-participant cohort [3] |
| Pivotal trial | 137 enrolled, 133 implanted, 132 in the published intention-to-treat cohort; 68% achieved at least 50% UUI reduction at 48 weeks (95% CI 60–76%) | 98% women, mean age 63.9 years; no sham or active comparator [4] |
| Two-year extension | 78% responders (95% CI 67–87%), 48% with at least 75% reduction and 22% dry at 96 weeks; 91.3% did not require additional OAB medications | 72 of 133 implanted participants completed 96 weeks [4][6] |
The pivotal report found device-related adverse events in 16% through 52 weeks.[4] The US patient manual counts 23 of 133 (17%) with device-related events and lists four related serious events (three infections and one contact dermatitis), all resolved by explant.[8] The same manual reports 75% responders in the per-protocol population at 48 weeks and 69% at 24 weeks (intention to treat).[8] The extension reported no serious or unanticipated events during that period. One serious wound-care event requiring intravenous antibiotics occurred in the feasibility trial. Most adverse events relate to wound healing at the implantation site.[2][3][4][5][6]
MRI and Other Safety Requirements
The manufacturer labels eCoin MR Conditional under specified 1.5 T and 3 T conditions, with the implant at least 20 cm from the edge of the scanner bore. The lower leg containing the implant must not enter the scanner. The patient magnet is MR Unsafe.[1] MRI review is model-specific.[1]
Other issues include poor local skin or vascular health, unhealed wounds, inability to operate the controller magnet, diathermy and possible interaction with other implanted electronics. The manufacturer provides specific electrosurgical precautions. Cardiac-device interactions require coordination, and the pivotal study excluded patients with implanted stimulators.[8] Lower-leg activity restrictions apply during healing, and the manual advises against activities that repeatedly flex the foot (for example gymnastics, mountain biking and skiing), diving below 8 m, hyperbaric exposure above 150 kPa and altitudes of 10,000 feet or more. Contraindications also include prior surgery in the implant area, pitting edema of 2+ or worse, and venous or arterial disease in the lower leg.[8] Safety and effectiveness are not established for pregnancy, age under 18, progressive neurological disease (such as Parkinson disease or multiple sclerosis) or bilateral implants. Shortwave, microwave and therapeutic ultrasound diathermy should not be used in patients with eCoin. Avoid monopolar electrosurgery, radiofrequency or microwave ablation, and radiation in the implant area. For necessary electrosurgery elsewhere, the manufacturer favors bipolar use at least 25 cm from the implant; if monopolar use is unavoidable, use the lowest effective setting and place the return pad far from eCoin on the contralateral side. When a cardiac device is present, the two should be implanted on opposite sides and as far apart as practical.[1][8]
Position Among Options
A patient may prefer automatic intermittent stimulation over repeated office visits or a wearable used for each treatment. That convenience is weighed against finite battery life, surgery, MRI restrictions and the limited comparative evidence. Single-arm trials provide no comparison of retention with medication or safety with SNM. Published follow-up extends to two years, so longer durability is unknown.[6]
The Medtronic implantable tibial neuromodulation system is a rechargeable leadless alternative. In the TITAN 2 single-arm pivotal study of 126 implanted participants, 59% had at least 50% UUI reduction at 6 months (95% CI 49–67%) and 61% at 12 months; 20% had device-, procedure- or therapy-related adverse events through 12 months. No head-to-head data exist, and the two trials' definitions and populations differ.[7]
For other choices, see PTNS systems, Revi, Altaviva and InterStim.
Videos
References
1. Valencia Technologies, part of Boston Scientific. eCoin Important Safety Information. Current manufacturer labeling summary. Indication, contraindications, MRI and controller instructions.
2. MacDiarmid S, Staskin DR, Lucente V, et al. Feasibility of a Fully Implanted, Nickel Sized and Shaped Tibial Nerve Stimulator for the Treatment of Overactive Bladder Syndrome With Urgency Urinary Incontinence. The Journal of Urology. 2019;201(5):967-972. doi:10.1016/j.juro.2018.10.017
3. Gilling P, Meffan P, Kaaki B, et al. Twelve-Month Durability of a Fully-Implanted, Nickel-Sized and Shaped Tibial Nerve Stimulator for the Treatment of Overactive Bladder Syndrome With Urgency Urinary Incontinence: A Single-Arm, Prospective Study. Urology. 2021;157:71-78. doi:10.1016/j.urology.2021.04.039
4. Rogers A, Bragg S, Ferrante K, Thenuwara C, Peterson DKL. Pivotal Study of Leadless Tibial Nerve Stimulation With eCoin® for Urgency Urinary Incontinence: An Open-Label, Single Arm Trial. The Journal of Urology. 2021;206(2):399-408. doi:10.1097/JU.0000000000001733
5. Bressington MJ, Scholtz D, Hooshiary A, et al. Device Evaluation: eCoin — Implantable Tibial Nerve Stimulator for Overactive Bladder. Expert Review of Medical Devices. 2023;20(11):899-904. doi:10.1080/17434440.2023.2254678
6. Lucente V, Giusto L, MacDiarmid S. Two-Year Pivotal Study Analysis of the Safety and Efficacy of Implantable Tibial Nerve Stimulation With eCoin® for Urgency Urinary Incontinence. Urology. 2024;194:17-23. doi:10.1016/j.urology.2024.07.046
7. Lee U, Xavier K, Carey J, et al. Implantable Tibial Neuromodulation Therapy Improves Symptoms of Urge Urinary Incontinence From the TITAN 2 Pivotal Study. The Journal of Urology. 2026;215(6):702-712. doi:10.1097/JU.0000000000004958
8. Valencia Technologies. eCoin Peripheral Neurostimulator System Patient Manual. Document 903-1236 Rev PB, 2020 (FDA P200036C), sections on stimulation, contraindications, clinical summary, physical activity, medical procedures and system specifications.