System of automatic measurement of the cornea's curvature rays with a slit lamp: automatic keratometer with slit lamp

• Grant number: 00/13218-4
• Support Opportunities: Research Grants - Innovative Research in Small Business - PIPE
• Start date: August 01, 2001
• End date: May 31, 2004
• Field of knowledge: Engineering - Biomedical Engineering - Medical Engineering
• Principal Investigator: Liliane Ventura Schiabel
• Grantee: Liliane Ventura Schiabel
• Company: Calmed Ltda. - ME
• City: São Carlos

Abstract

The basic objective of the present project is the development of a piece of equipment for clinical use which is simple to operate, but automated and precise, which offers measurement of curvature rays of the human cornea, or rather, automatic keratometry. This equipment will be adapted to the Split Lamp (ocular biomicroscope available in all ophthalmological clinics), and which will be able, at low cost, to carry out quickly the measurements described above. The system consists of capturing the reflection from the projection of a luminous ring sight in the patient’s cornea, through an optical system and a detector of the CCD type. The image of this reflection is sent to a PC type microcomputer via a video capturing board in real time. The image is analyzed afterwards by a computer program which will provide the rays of greater and lesser curvature and the respective associated axes, of the analyzed surface, in relation to the deformity of the reflected image of the ring. In Brazil, manual and automatic equipment exists for keratometric measurements, but it is all imported and expensive. The system proposed here offers, in addition to speed of obtaining measurements and the presentation of the final results, depth of scale up to 30D, precision in ray of curvature and axis comparable to manual keratometers, respectively, the advantage of low cost. Phase 1 of the project may be considered a success, in view of the enormous interest of other companies in the sector in commercializing the equipment and/or obtaining patent licenses. Thus, in order to cater for clinical needs and market interest, phase 2 will consist of perfecting the system with an LED and also it will be miniaturized. (AU)

Filed patent(s) as a result of this research project