Closed-Loop Responsive Neurostimulation (RNS) for Refractory Epilepsy

Closed-Loop Responsive Neurostimulation · RNS Smart Interception

国家药监局 NMPA 创新医疗器械特别审查 / 临床研究注册 (NCT04561284) · Class III Innovative Neuromodulation Device / AI-Driven Epilepsy Breakthrough

Co-developed by Xuanwu Hospital (Prof. Guoguang Zhao) and Tsinghua University, the Closed-Loop Responsive Neurostimulation (RNS) system transforms intractable epilepsy care for patients whose foci overlap critical motor or language speech areas. Unlike conventional continuous DBS, the RNS neurostimulator monitors intracranial electrocorticograms (ECoG) 24/7. When automated algorithms detect incipient epileptiform spikes, it delivers targeted micro-bursts within milliseconds to abort the seizure before clinical manifestations emerge.

Median Seizure Frequency Reduction

75.0% (长期随访达 82.0%)

Control: 14.2%

Evidence Level

ILAE and AAN Guidelines Class I Level A Recommendation

Xuanwu Hospital (Capital Medical University) & Tsinghua University

Treatment Course

3-5 Days MDT Workup

Periodic clinical follow-up with regimen optimization

Global Advantage

Direct Billing Available

Mechanism of Action (MOA)

24/7 Cortical ECoG Sensing + AI Seizure Pattern Detection + Subsecond Closed-Loop Abort

1

Craniectomy-Flushed Flush Implantation: Ultra-thin stimulator integrates flush with the cranium under the scalp, invisible and cosmetically pristine.

2

Stereotactic Robotic Multi-Target Placement: Depth or strip leads placed precisely at bilateral seizure onsets (e.g., mesial temporal, motor cortex).

3

Embedded AI Spike Recognition: Real-time algorithm detects electrographic onset within milliseconds based on line-length and frequency shifts.

4

Subsecond Disruption & Telemetry: Delivers targeted charge-balanced pulses aborting seizure spread; data wirelessly syncs to clinical databases.

Patient Profile & Indications

Quantified entry criteria and stages for foreign referral

Medically refractory focal onset epilepsy failing >=3 appropriate antiepileptic drug regimens.

Epileptogenic foci localized to bilateral brain regions (e.g., bilateral mesial temporal lobe onset) where resection is contraindicated.

Seizure onset located in eloquent cortex (Broca's speech area, primary motor cortex) where resection would induce irreversible deficits.

Patients with persistent disabling seizures despite prior surgical resection or vagus nerve stimulation.

Strict Exclusion Red Lines

• ✕Generalized epilepsy syndromes (idiopathic generalized epilepsy with absence or generalized spikes).
• ✕Diffuse or multifocal epileptogenic zones (>2 independent non-contiguous foci).
• ✕Severe psychiatric disorders, active psychosis, or progressive neurodegenerative disease.
• ✕Requirement for repetitive high-power full-body MRI examinations.

Clinical Trial Data & Real-World Outcomes

China National Multicenter Closed-Loop RNS Prospective Study

Median Seizure Frequency Reduction

75.0% (长期随访达 82.0%)

Disease Control (DCR)

91.5%

Evidence Grade

ILAE and AAN Guidelines Class I Level A Recommendation

Safety Profile: Memory and cognitive scores preserved or improved over long-term follow-up; zero permanent resection-related neurological deficits; infection rate <2.1%.

Official Regulatory Registries & Authoritative Sources

Direct verification links to NMPA, ClinicalTrials.gov, PubMed and CSCO/FDA registries

Neurology Landmark

Neurology: Nine-Year Prospective Safety and Efficacy of the RNS System

NMPA Priority

NMPA Innovative Medical Device Special Review

Global Approved Competitor Benchmark

Head-to-head comparison with US, EU, and Japanese approved equivalents

Technique / Device / Brand	Developer	Mechanism / Platform	Clinical Indications	Approval & Region	Relative Cost
Closed-Loop Responsive Neurostimulation (RNS)Selected	Xuanwu Hospital / Tsinghua University	Cranially Implanted Neurostimulator & Intracranial Leads	Bilateral Foci · Eloquent Cortex Refractory Focal Epilepsy	China (NMPA Priority Innovation Channel)2023	~1/6 to 1/8 of US commercial charges

Benchmark Hospital Centers

Pioneer institute in closed-loop responsive neurostimulation with world-class robotic stereotactic surgical expertise.

Xuanwu Hospital, Capital Medical University

Functional Neurosurgery & Comprehensive Epilepsy Center

Prof. Guoguang Zhao & Prof. Yongzhi Shan

Collaborating with Tsinghua Brain-Computer Interface Lab, leading cutting-edge neuromodulation algorithm optimization.

Tsinghua University Yuquan Hospital

Epilepsy Center & Clinical Electrophysiology

Prof. Wenjing Zhou

Premier South China hub providing comprehensive video-EEG evaluation and cloud-based tele-programming.

Foshan Chancheng Hospital (FIMC International Medical Center)

Functional Neurosurgery & International Medical Center

FIMC Neuromodulation Team

Required Medical Records:

•Continuous 24-72 hour long-term video-EEG (VEEG) recording ictal onsets and interictal spikes.

•High-resolution 3.0T brain MRI epilepsy protocol (thin-slice coronal T2/FLAIR assessing hippocampal anatomy).

•Prior SEEG intracranial monitoring reports detailing specific contact points of seizure initiation, if available.

•Comprehensive 12-month medication log with daily dosages, blood drug levels, and seizure diary.