OC-OMRA-S Mainster (Standard) Focal/Grid
■ The Mainster Focal/Grid Laser Lens provides high lateral magnification which offers excellent retinal detail while its high axial magnification permits appreciation of subtle intraretinal details and retinal thickening.
■ It offers high retinal resolution, excellent visibility through hazy media and minimal beam astigmatism in the field periphery.
■ It is the lens of choice for diagnosing and treating macular edema in diabetic retinopathy and branch retinal vein occlusion.
■ No methycellulose is required during routine eye examinations on the OMRA-S-2 style.
■ As with any indirect ophthalmoscopy contact lens, some time is needed to become familiar.
Suggestions for use are:
- Use the slit lamp with its illumination and observation arms lined up so that illumination and observation are parallel.
- Use a vertical slit beam with the illumination beam as narrow and short as possible to minimize back-scattered slit lamp light that can decrease image contrast.
- Use slit lamp magnification between 5x and 12x.
- Tilt the lens on the patient's cornea to select your viewing area and optimize image clarity and stereoscopic view.
- Keep the front surface of the lens perpendicular to the viewing axis and the laser beam.
- Have the patient turn their eye slightly for larger changes in viewing area location.
■ Since this lens presents an image in air rather than within the lens, the slit lamp must be moved further back from the patient's eye, as compared with conventional lenses. It is sometimes helpful to start by using the lowest slit lamp magnification with the lens centered in the field of view, then move the slit lamp away from the patient until the image is acquired.
■ Restricted posterior movement of the older Zeiss 125 slit lamp requires the patient's forehead be moved backward from the headrest. This positioning may be achieved by placing a one inch thick sponge strip between the patient's forehead and the headrest.