PRK-7000 Auto Refractometer / Keratometer

The POTEC PRK-7000 at MCR, Kannur, supports eye assessment with measurements of refractive error and corneal curvature, alongside your clinician's examination.

What does the PRK-7000 measure?

The PRK-7000 combines two functions. Auto-refraction provides an objective estimate of the eye's focusing error. Keratometry measures the curvature of the cornea, the clear front surface of the eye. POTEC describes combined refraction and keratometry measurement, alignment guidance and immediately viewable results. [1]

These measurements provide information for the eye-care team to consider with your symptoms and other tests. The instrument's reading is a starting point for assessment, rather than an instruction to order spectacles without professional review.

Why refraction matters for everyday vision

The cornea and lens bend light so it focuses on the retina. Refractive errors occur when that focusing does not work correctly. Nearsightedness, farsightedness and astigmatism can affect clarity at different distances; age-related presbyopia affects near focusing. Blurred vision, eyestrain or difficulty with existing glasses are reasons to arrange an eye examination. [2]

At your visit, describe the activities that are difficult, such as reading, screen work or seeing distant objects. This gives the clinician useful context for the measurements and the discussion of visual correction.

Understanding the terms on a measurement printout

The PRK-7000 specification lists sphere, cylinder, axis and corneal-curvature measurements. [1] Your clinician can explain what is relevant to your report:

• Sphere: a focusing-power measurement, expressed in dioptres.
• Cylinder and axis: measurements used to describe an astigmatic component and its orientation.
• Keratometry: measurements describing the corneal surface's curvature.

Ask how the instrument readings relate to your final clinical assessment. You do not need to interpret the abbreviations or choose a prescription yourself.

What to expect during the assessment

A typical measurement involves positioning in front of the instrument, keeping the head steady and following the operator's instructions about where to look. Readings are taken for each eye and may be repeated if alignment or fixation needs adjustment.

The wider appointment may include reading letters at different distances and further examination according to your needs. [2] Tell the team if you have difficulty maintaining the required position so they can discuss how to proceed.

Preparing for your visit

• Bring your current spectacles and earlier prescriptions or eye reports.
• Tell the team about contact lens use, previous eye surgery and current eye drops.
• Explain whether the change in vision is recent, intermittent or affecting particular activities.
• Mention diabetes and bring relevant recent reports to help coordinate the consultation.

Ask the clinic in advance whether any preparation is needed for the tests planned at your appointment. Contact lens instructions and the need for additional tests depend on the assessment.

Where this fits in diabetic eye care

Refraction addresses focusing and visual correction. A comprehensive eye examination also checks eye health, and can include pressure measurement and dilation to inspect internal structures. [3] Your clinician decides which parts of the assessment you need.

For retinal imaging, read about MCR's Remidio fundus camera. Ask the team which vision and retinal checks are planned for your visit rather than assuming that one instrument covers every aspect of eye health.

After the measurements

Discuss the findings, any further assessment and the next step with your clinician. If other parts of the visit require pupil-dilating drops, ask about temporary effects on vision and transport home. [3] To arrange a vision assessment, contact MCR in Kannur.