Pinhole vision and lack of vision

Just finished a week of tutorials at the new eye clinic in Manchester. During this we discussed when to use an Amsler grid. As low-tech as this is, it is still easy for patients to understand for self monitoring and is a useful indicator of central distortion. The list of indications for its use we came up with was as follows;

- if the macula looks anything other than acceptable on ophthalmoscopy

- if there is any report at all of central vision changes

- if there is any unexplainable reduction in acuity.

Less significant might be the need to assess the central red field if a patient is using a maculopathic inducing drug like tamoxifen. Another symptom that sometimes indicates macular problems is where there is a reduced photostress recovery time. I have had patients concerned that, having had a photo taken at a wedding, they have noticed the purple after-image for a long time afterwards - cue the Amsler.