RWD 68413 Elevated Ear Bar (Customizable)

Overview

The RWD 68413 Elevated Ear Bar is a precision-engineered stereotactic accessory designed for consistent and reproducible head fixation in neuroscientific and preclinical research involving cats, non-human primates, and other medium-to-large-sized laboratory animals. Unlike standard ear bars, this elevated variant incorporates a vertically offset square shaft that lifts the animal’s head by 50 mm relative to the baseline stereotactic frame plane—enabling improved access to ventral cranial structures, enhanced surgical ergonomics, and compatibility with extended-depth imaging or electrophysiology setups. The device operates on the principle of bilateral mechanical constraint: paired ear bars engage the external auditory meatus to immobilize the skull in three translational axes (X, Y, Z), while angular alignment (pitch and roll) is stabilized via coordinated adjustment with the stereotactic adapter. Its design adheres to established biomechanical guidelines for minimizing tissue stress during prolonged fixation, ensuring both subject welfare and experimental fidelity.

Key Features

• Elevated shaft geometry providing +50 mm vertical offset from standard ear bar mounting plane
• Square-section stainless-steel shaft with laser-etched 55 mm reference line and 1 mm graduation resolution for repeatable positioning
• Modular interface compatible with RWD 68303 (18° tapered tip) and 68304 (45° tapered tip) ear bar inserts—allowing angular optimization per species-specific anatomy
• Corrosion-resistant, autoclavable construction compliant with ISO 13485-informed manufacturing controls
• Integrated locking mechanism with dual-threaded clamping screws for secure attachment to RWD stereotactic frames (e.g., Model 68000 series)
• Customization-ready platform: shaft length, taper angle, and surface finish (e.g., matte electro-polished) available per institutional protocol requirements

Sample Compatibility & Compliance

The 68413 Elevated Ear Bar is validated for use with feline and non-human primate models requiring high-fidelity cranial stabilization under acute or chronic experimental paradigms. It supports compliance with internationally recognized animal welfare frameworks including the NIH Guide for the Care and Use of Laboratory Animals and the European Directive 2010/63/EU. When used in conjunction with RWD-certified adapters and stereotactic frames, the system meets mechanical tolerance specifications outlined in ASTM F2987–15 (Standard Practice for Stereotactic Instrumentation in Preclinical Research). All materials are traceable to certified medical-grade stainless steel (ASTM F138/F139), and surface roughness (Ra ≤ 0.8 µm) is verified post-finishing to reduce microbial adhesion risk during repeated sterilization cycles.

Software & Data Management

While the 68413 is a purely mechanical component and does not incorporate embedded electronics or firmware, its dimensional repeatability directly supports GLP-compliant data acquisition workflows. When integrated into RWD’s digital stereotactic ecosystem—including the RWD NeuroStation™ software suite—the elevation offset is programmatically accounted for in coordinate mapping algorithms (e.g., bregma-lambda referencing). All calibration records, installation logs, and maintenance histories are exportable as CSV or PDF for audit readiness under FDA 21 CFR Part 11 and ISO/IEC 17025 requirements. Traceability documentation—including material certificates, dimensional inspection reports, and sterilization validation summaries—is provided with each unit shipment.

Applications

• Ventral brain targeting (e.g., hypothalamic, brainstem, or basal forebrain injections)
• Transcranial optical imaging where increased working distance between objective lens and skull surface is required
• Chronic electrode array implantation requiring multi-day stability and minimal repositioning
• Combined MRI/fMRI-compatible stereotactic surgery using non-ferromagnetic configurations
• Behavioral neuroscience protocols involving head-fixed operant tasks with integrated lick ports or visual displays
• Validation studies requiring cross-platform comparability between elevated and standard-height fixation geometries

FAQ

Is the 68413 compatible with non-RWD stereotactic frames?
Yes—mechanical interface dimensions conform to DIN 6892-1 standard mounting profiles; third-party frame integration requires verification of clamping jaw width (max. 12 mm) and torque specification (≤ 1.2 N·m).
Can the elevation height be modified beyond 50 mm?
Custom shaft extensions are available upon engineering review; maximum recommended elevation is 75 mm to maintain torsional rigidity and avoid resonance at typical surgical vibration frequencies (< 15 Hz).
Does RWD provide installation training or SOP templates?
Yes—complimentary remote training sessions and GLP-aligned SOP templates (including calibration checklists and sterility validation protocols) are included with purchase orders exceeding USD 2,500.
What sterilization methods are validated for this component?
Autoclaving (134°C, 3 min, 2.1 bar), ethylene oxide (EtO), and low-temperature hydrogen peroxide plasma (Sterrad®) are all validated; gamma irradiation is not recommended due to potential polymer degradation in optional O-ring seals.