NPC (NEAR POINT OF CONVERGENCE)

#NPC
#OPTOMETRY
#OPHTHALMOLOGY
#EYEHEALTH
#VISIONTHERAPY
#BINOCULARVISION


NPC (NEAR POINT OF CONVERGENCE) is the prime finding in the diagnosis of convergence insufficiency and a practical technique of finding the point of all lines of sight of the eyes when maximum convergence is utilized.
It is the measurement of maximum ability of a patients eyes to converge, Patients who have reduced near point of convergence distances may have visual and ocular discomfort when performing near point vision tasks and also many patients manifest symptoms only after several minutes of near task.

Here the test is performed using RAF(Royal Air Force) Ruler,the square rule which holds the rotating cubical drum of 50cm long.The four sides of ruler are 1.a centimeter scale 2.a corresponding equivalent dioptric scale 3.expected age scale 4.scale indicating the positions of normal and abnormal convergence range.,To measure NPC the dot and line is the standard target.
The subjective break point is indicated when the patient either reports diplopia and recovery is noted when the patient reports one target when the slide is slowly moved back.
The objective values of break and recovery to binocularity are noted when the examiner notices the one or both eyes diverge from fixation and when both eyes regain triangulation on the target,respectively.

points to be remembered
1.Always Introduce yourself to the patient also explain about the test before performing.
2.Perform the test in bright room,with the correction of the patient wearing it and perform the test over the correction (spectacles,contactlens).
3.Subjective NPC:Patient reports sustained Diplopia,recovery,Whereas in Objective NPC,Clinician observes point when one eye turns out.
4.Repeat the test 3 times minimum and record the readings.