If the reflex moves with the sweep, move the trial power in the plus direction toward neutrality.
Loading…
Practise reflex motion, principal meridians and neutralization with working-distance correction.
Sit or stand facing the patient at your chosen working distance. Ask the patient to fixate on a distant target to reduce accommodation as much as possible.
Hold the instrument comfortably with the viewing aperture aligned to your eye and your thumb or index finger free to rotate the streak sleeve. A common technique is right hand/right eye for the patient's right eye and left hand/left eye for the left eye.
Sweep the streak across the pupil and observe the reflex direction, speed and width. Rotate the streak to identify the principal meridians, then sweep perpendicular to the streak orientation.
Adjust trial lenses until the reflex broadly fills the pupil and relative motion disappears. In astigmatism, neutralize the two principal meridians separately.
After gross neutralization, subtract the dioptric power of the working distance from the spherical component to obtain the net estimate.
Note: grip, sleeve and control details vary by retinoscope model, so the exact hand movements may differ between instruments.
If the reflex moves with the sweep, move the trial power in the plus direction toward neutrality.
If the reflex moves against the sweep, move the trial power in the minus direction toward neutrality.
After gross neutralization, subtract the working-distance power from the spherical component.