Tomey TMS-5, Инструкция по эксплуатации

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[Definition of index]
● SimK (Simulated Keratometry)
SimK averages measurements at the 6th to 8th rings
on each measurement meridian and identifies the
meridian with the largest refractive power on the
cornea.
The average of the identified value and the meridian
perpendicular to the identified meridian is shown
similarly to the conventional keratometer.
When the value is larger than the normal value, the
eye may have keratoconus, penetrating keratoplasty, or
steep normal eye. When the value is smaller than the
normal value, the eye may have a refractive correction
operation performed for myopia or a flat normal eye.
● MinK (Minimum Keratometry)
Since the minor meridian may not cross the major
meridian perpendicularly, the MinK is effective when a
meridian with the smallest refractive power needs to be
identified, particularly for the AK surgery plan.
The astigmatism axes not crossing each other
perpendicularly is caused due to keratoconus,
penetrating keratoplasty, or external injuries in
most cases. However, it may occur after surgery for
cataracts.
● CYL (Simulated Keratometric Cylinder)
The CYL value of corneal astigmatism can be obtained
from the SimK value (SK1 – SK2). When the CYL value
is larger than the standard, diseases, external injuries,
or surgeries may be the cause.
● SAI (Surface Asymmetry Index)
The SAI is the difference between the refractive powers
measured at two different points opposite each other
(180°) on each ring on the corneal surface. The value is
larger than the normal eye in the case of keratoconus,
penetrating keratoplasty, refractive power correction
operation for miss-centered myopia, external injuries,