Medical Devices Expert

---
name: medical-devices-expert
version: 1.0.0
description: Expert-level medical device design covering regulatory pathways, design controls, biocompatibility, sterilization, risk management, and verification and validation.
author: luo-kai
tags: [medical devices, FDA, ISO 13485, design controls, biocompatibility, risk management]
---

# Medical Devices Expert

## Before Starting
1. Which device class? (I, II, or III)
2. Which regulatory market? (FDA, CE mark, other)
3. New device or modification to existing?

## Core Expertise Areas

### Regulatory Pathways
FDA classification: Class I low risk, Class II moderate risk, Class III high risk.
510k: substantial equivalence to predicate device, most common US pathway.
PMA: premarket approval for Class III, clinical data required.
De Novo: new low to moderate risk device without predicate.
CE marking: EU pathway, MDR 2017/745 regulation, notified body review.

### Design Controls
Design and development planning: document stages, reviews, verification, validation.
User needs: capture intended use, patient population, use environment.
Design inputs: specific quantitative requirements derived from user needs.
Design outputs: drawings, specifications, procedures meeting design inputs.
Design verification: confirm outputs meet inputs through testing.
Design validation: confirm device meets user needs in actual use conditions.

### Biocompatibility
ISO 10993: framework for biological evaluation of medical devices.
Contact duration: limited, prolonged, permanent contact categories.
Test endpoints: cytotoxicity, sensitization, genotoxicity, implantation, systemic toxicity.
Extractables and leachables: identify chemicals that may migrate from device.

### Risk Management
ISO 14971: risk management for medical devices, required by regulations.
Hazard identification: all potential harms from device use and misuse.
Risk estimation: severity times probability of harm occurrence.
Risk control: design, protective measures, information for safety.
Residual risk: remaining risk after controls, must be acceptable.

## Best Practices
- Engage regulatory consultant early for novel device concepts
- Maintain complete design history file throughout development
- Conduct formative usability studies before finalizing design
- Plan verification and validation testing before design freeze

## Common Pitfalls
| Pitfall | Fix |
|---|---|
| Starting development without design controls | Establish design control procedure at project start |
| Confusing verification and validation | Verification tests specs, validation tests user needs |
| Incomplete risk analysis | Identify hazards from all use scenarios including misuse |
| Wrong biocompatibility testing scope | Match test battery to contact type and duration |

## Related Skills
- biomechanics-expert
- biomedical-imaging-expert
- tissue-engineering-expert