CAS-R-2 Frameless Stereotactic System

The CAS-R-2 Frameless Stereotactic System, developed by Hozmedical, represents one of China’s earliest domestically developed neurosurgical robots. First approved by NMPA in 2002, it pioneered frameless stereotactic technology in Chinese neurosurgery, eliminating the need for traditional head frames while achieving sub-millimeter positioning accuracy.

Product Overview

The CAS-R-2 emerged from the National 863 Program as a collaborative effort between Tsinghua University and the PLA Navy General Hospital. Unlike conventional frame-based stereotactic systems that require painful pin fixation to the skull, the CAS-R-2 uses surface markers (fiducial marks) attached to the patient’s head for registration, enabling surgery under local anesthesia with reduced patient trauma.

The system has received NMPA approval four times through successive iterations and is included in China’s national medical insurance reimbursement system. With nearly 100,000 procedures completed across 100+ hospitals, it has established a substantial clinical track record without reported adverse events.

Key Features

At under 0.8mm clinical positioning accuracy — roughly one-third the error of the ROSA system — the CAS-R-2 enables precise targeting of deep brain structures through frameless optical-marker registration.

• Frameless Operation: Eliminates rigid head frame fixation using optical marker-based registration, reducing patient discomfort and expanding eligibility to infants and patients unsuitable for frame-based procedures

• High Positioning Accuracy: Achieves actual clinical accuracy within 0.8mm, compared to 2mm for the ROSA system, enabling precise targeting of deep brain structures

• Full Workflow Coverage: Integrates surgical planning, navigation, and robotic positioning in a single platform, covering the entire surgical process from preoperative imaging to intraoperative guidance

• 100% Domestic Components: All core technologies and components are manufactured domestically, ensuring responsive maintenance support and lower consumable costs

• Cost Efficiency: Priced at approximately 30% of ROSA and one-tenth of comparable imported systems, enabling adoption in resource-limited settings

Technical Specifications

At under 0.8mm clinical accuracy across nearly 100,000 procedures, the CAS-R-2 combines a 5-DOF arm with CT/MRI-compatible optical marker registration and integrated planning-to-navigation software.

Clinical Applications

The CAS-R-2 supports a broad range of neurosurgical procedures spanning emergency care, oncology, and functional neurosurgery:

Emergency Procedures

• Cerebral hemorrhage evacuation
• Brain abscess drainage
• Intracranial foreign body removal

Oncology Applications

• Stereotactic brain biopsy
• Intracranial tumor brachytherapy
• Chemotherapy capsule implantation (Ommaya reservoir)

Functional Neurosurgery

• Deep brain stimulation (DBS) electrode implantation for Parkinson’s disease, dystonia, and essential tremor
• Stereo-electroencephalography (SEEG) for epilepsy evaluation
• Deep brain nucleus ablation

Surgical Assistance

• Microscope-assisted tumor surgery positioning
• Ventriculoscope-assisted surgery guidance

Regulatory Status

The CAS-R-2 received the National Science and Technology Progress Award (Second Class) in 2008. The product is covered under China’s medical insurance reimbursement, reducing out-of-pocket costs for patients.

Clinical Evidence

The system has been installed in over 100 hospitals across China, including:

• Huashan Hospital (Fudan University)
• Xuanwu Hospital (Capital Medical University)
• PLA Army General Hospital
• Tiantan Puhua Hospital
• First Affiliated Hospital of Zhengzhou University

Clinical data encompasses nearly 100,000 procedures with no reported adverse events, demonstrating consistent safety across diverse surgical applications and hospital settings.

Competitive Positioning

Compared to the ROSA system (Zimmer Biomet), the CAS-R-2 offers:

The CAS-R-2’s broader indication coverage—including emergency cerebral hemorrhage procedures common in grassroots hospitals—addresses clinical needs not typically served by imported systems.

Frequently Asked Questions

What is the accuracy of the CAS-R-2 system?

The CAS-R-2 achieves clinical positioning accuracy within 0.8mm, validated across nearly 100,000 procedures. This precision enables targeting of small deep brain structures for DBS electrode placement and tumor biopsy.

Can the CAS-R-2 be used for Parkinson’s disease treatment?

Yes, the CAS-R-2 supports deep brain stimulation (DBS) electrode implantation, a standard treatment for medication-refractory Parkinson’s disease. The frameless design reduces procedure time and patient discomfort compared to frame-based approaches.

How does frameless stereotaxy work?

Instead of fixing a rigid frame to the skull with pins, the CAS-R-2 uses adhesive fiducial markers placed on the patient’s scalp. These markers appear on preoperative CT/MRI images and are optically tracked during surgery, allowing the system to register the patient’s anatomy without painful frame attachment.

Is the CAS-R-2 covered by insurance in China?

Yes, the CAS-R-2 is included in China’s national medical insurance reimbursement system, reducing patient financial burden for robotic-assisted neurosurgical procedures.