Links:

https://www.indiatoday.in/health/story/ai-blood-test-tool-niloufer-hospital-non-invasive-diagnostics-telangana-quick-vitals-2727989-2025-05-21

https://www.thehindu.com/news/cities/Hyderabad/niloufer-hospital-in-hyderabad-launches-ai-based-non-invasive-blood-test-tool/article69596981.ece

The article describes an AI-powered blood test tool, an app that leverages advanced face-scanning technology to provide rapid, non-invasive health diagnostics.

Here's a technical gist of how it works:

• Technology: The core technology is Photoplethysmography (PPG), which detects changes in light absorption through the skin to assess vital health parameters.
• Measurement Capabilities: The tool can measure a wide range of vital parameters within 20 to 60 seconds, including:
  • Blood Pressure
  • Oxygen Saturation (SpO2)
  • Heart Rate
  • Respiration Rate
  • Heart Rate Variability (HRV)
  • Hemoglobin A1c
  • Stress Levels
  • Pulse Respiratory Quotient (PRQ)
  • Sympathetic and Parasympathetic Nervous System activity
• Monitoring Options: Beyond quick spot checks via face scanning, the system also supports continuous monitoring for patients using wearable contact-based PPG sensors.
• Data Management and Compliance: The tool allows for the registration of multiple users and ensures that patient data is shared securely only with authorized healthcare providers, complying with Indian regulatory norms around medical data handling.

How Photoplethysmography (PPG) Works

Photoplethysmography (PPG) is a non-invasive optical technique that detects changes in blood volume in your tissue, typically at the skin surface. It's the core technology in smartwatches for heart rate and pulse oximeters for blood oxygen.

Here's the concise breakdown:

1. Light Emission: An LED emits light (green for heart rate, infrared for oxygen) into your skin.
2. Light Absorption: Blood absorbs more light than surrounding tissues.
3. Blood Volume Changes: With each heartbeat, blood volume in your vessels changes, leading to variations in light absorption. More blood means more absorption, less blood means less.
4. Light Detection: A photodetector measures the amount of light either reflected or transmitted back.
5. Signal Conversion: This detected light is converted into an electrical signal that fluctuates with your pulse.
6. Data Processing: Algorithms analyze this signal (the pulsatile "AC component" for heart rate, and the "DC component" for baseline absorption) to derive physiological parameters.

In short, PPG works by shining light into your skin and then measuring how the light absorption changes with your pulsating blood flow, allowing it to "see" your pulse and other vital health data.