ScoutPro Osmolarity System
Abstract
The ScoutPro Osmolarity System is intended to measure the osmolarity of human tears to aid in the diagnosis of Dry Eye Disease in patients suspected of having the condition, in conjunction with other methods of clinical evaluation.
ScoutPro is the first and only portable osmometer in the United States, designed to help advance corneal health decisions for today's busy eye care practices.
Measurement Technology — VeriLyte™
The ScoutPro Test utilizes a temperature-corrected impedance measurement to provide an indirect assessment of osmolarity. After application of a calibration curve to the steady-state electrical impedance of the tear fluid, osmolarity is calculated and displayed as a quantitative numerical value in mOsm/L. No calculations are required by the user.
VeriLyte™ Technology integrates specimen collection and analysis all within the ScoutPro pen itself.
Measurement Range & Clinical Thresholds
The ScoutPro measurement range is linear from 275–400 mOsm/L. Test results outside this range will be reported as either "Below Range" (below 275 mOsm/L) or "Above Range" (above 400 mOsm/L). Osmolarities outside the stated range are very rare and should generally be confirmed with a subsequent test, as values outside the measurement range may be indicative of an error.
An osmolarity referent value of 316 mOsm/L was found to yield sensitivity of 69%, specificity of 92%, and an overall predictive accuracy of 82% for the diagnosis of Dry Eye Disease.
Sample Requirements
Testing only requires a very small 50 nanoliter volume of tears, enabling osmolarity testing on even the driest eyes. This is a key clinical advantage over other methods that require larger sample volumes.
Speed & Workflow
Real-time results appear on the pen within seconds of tear sample collection, with no need to dock the pen to analyze the tear sample.
The ScoutPro can measure osmolarity in less than 1 minute for both eyes, a major time saving compared to, for example, the Schirmer's test which can take up to 7 minutes.
Hardware & Device Specs
| Feature | Detail |
|---|---|
| Form Factor | Handheld pen — fully portable |
| Display | LCD screen on the pen |
| Memory | Stores up to 2 prior test results |
| Battery | Rechargeable AAA batteries; 8-hour battery life |
| Charging Base | Small footprint; optional wall mount |
| Test Cards | Interchangeable with first-generation TearLab osmolarity system |
The LCD screen displays results in seconds, the rechargeable AAA batteries hold a charge for 8 hours, and test cards are interchangeable with the first-generation TearLab osmolarity system, backed by a trusted precision record of 24 million tests.
Validation & Accuracy
The correlation study was performed internally by the manufacturer using contrived tear samples of various osmolarity levels within the clinical reference range, comparing both the ScoutPro and the Wescor Model 5520 vapor pressure osmometer calibrated to NIST-traceable standards.
The system is built upon the company's established accuracy trusted in over 24 million tests globally, with industry-leading precision.
Regulatory Status
The ScoutPro Osmolarity System is a CLIA Waived test system for human tears. Each laboratory or testing site using the ScoutPro must have a CLIA Certificate of Waiver before starting testing. The ScoutPro is a waived test so long as it is used according to the instructions in the Package Insert — any modification by the laboratory to the test system or instructions will result in the test no longer meeting the requirements for waived categorization.
Intended Users
Operators of the device are eye care practitioners including Ophthalmologists, Orthoptists, Optometrists, Ophthalmic Assistants, Ophthalmic Technicians, and Ophthalmic Medical Technicians.
Warranty
The ScoutPro is warranted against defects in material and workmanship for 12 months from the date of delivery. The warranty excludes consumable items such as Test Cards and is nontransferable.
Scientific Context
Tear osmolarity is a direct marker of tear film homeostasis. Hyperosmolarity activates inflammatory cascades on the ocular surface and is recognized as a core mechanism of Dry Eye Disease. The ScoutPro's impedance-based approach enables point-of-care testing that was previously limited to bench-top osmometers, making it particularly valuable in high-volume cataract and refractive surgery practices where dry eye can significantly affect surgical outcomes.
Visreed