You don't check near vision?!!!
Some techs that I work with don't bother to check near vision. I'm talking about at the beginning of the exam, when you check distance vision. There are various reasons given: "It takes too much time", "My doctor doesn't care if I do it or not", and "What good does it do, anyway?" I'm glad you asked. There are two good reasons to check near vision.
Reason #1: Useful information regarding the patient's refractive state can be gleaned from the near vision measurement.
Reason #2: Userful information regarding glasses difficulties can be gleaned from the near vision measurement. For many patients, the refraction/glasses evaluation is the most important part of the examination, particularly if the patient has no ongoing disease process (e.g. dense cataracts, glaucoma, AMD). Most patients rightly expect a good pair of glasses that function well at distance and near. How do you know about how the patient functions at near unless you observe them trying to read?
Let's talk about how to measure near vision and see how the above reasons come into play:
1. If glasses are needed for near, you will obviously want to check the near vision with correction. Checking near vision without correction generally does qualify as a waste of time, unless that is the normal mode for the patient.
2. Provide good lighting. The ceiling light is usually not good enough. It is best to position the reading light of the instrument stand so that light is coming over the patients shoulder.
3. Hand a reading card to the patient and point out on the card which line that you want him/her to read. Don't use the occluder at this point. I like to start with the small numbers and work my way up, so initially I point to the Jaeger 1 (20/25) line. Allow the patient to hold the card at whatever distance seems comfortable and tell the patient to hold the card at whatever distance seems to work for them. Observe the behavior of the patient as he/she attempts to read the J1 line. The patient who can immediately read the numbers with little effort is probably already in good shape in this department. The patient who has to push progressive lenses up to see better, either needs a frame adjustment or needs more plus power for reading.
Notice the distance at which the patient is holding the card. If the distance is shorter than the standard 14-16 inches, then the patient may be overplused at near (unless the patient has low vision). If the distance is greater than 14-16 inches, the the patient may be underplused at near. Ask the patient what his/her preferrence is in terms of reading distance.
Does the patient have a hard time "finding" the right place to look through in the lenses? If so, it's your job to find out why. If the correction is OK, then perhaps the lens type is wrong (flat top vs progressive), or maybe all that is need is some instruction and/or frame adjustment.
4. Now check each eye individually using the occluder. You hold the occluder, otherwise this task may take forever. For some reason, people have a hard time holding an occluder and a near card at the same time. I suppose it's like patting your head and rubbing your stomach at the same time. Have the patient hold the card at his/her "normal" distance. Many times, an eye will see a little better at near than in the distance. For example, 20/40 distance, 20/30 or 20/25 at near, particularly if the near add is stronger than +2.50, due to proximal magnification. If there is a big discrepancy distance/near, such as 20/70 distance and J1 (20/25) near, this tells you that the glasses prescription is off and that you will likely find a refractive change when measured.
In summary, measuring near vision gives you useful clues as to the refractive state and the patient's visual performance at near. Contrary to being a waste of time, this information can save you time by pointing you in the right direction regarding the needs of the patient.