The College of Optometrists

hiya, had a 22 yr old patient come in today c/o not being able to read number plates, his last eye test was 6 months ago but he still wanted another one..I wasn;t going to argue so I did the test. He had been wearing his old spex (not from 6 months ago) which were -3.25/-0.75 and LE -3.25/-0.50, 6 months ago the pre reg optom found -3.25/-0.75 and LE -3.50/-0/25 After subjective in which I really pushed the plus I found: -3.75/-1.00 and LE -4.00/-0/25, I put him down to -3.75 in the RE but should I have given him his full Rx?

To top it off whilst doing Ocular Motility he was getting diplopia on elevation. He was ortho straight ahead and on downgaze and terribly exo on upgaze-is this a Vexo? Looking at him after this I noticed he had a slight chin elevation and face turn to the left. Thing is when I told him to put his head straight and physically did it he did not report diplopia. FD showed no slip. NPC and acc was within normal limits. I referred him for an orthoptic assessment on the basis this has never been investigated before but what I would really like to know is what was wrong with this patient!!!????

how interesting! I guess you enjoyed this one! Well done to notice all the little aspects that make up the case.

1) most Rx is give or take 0.25 - so he will like his RE -3.75 fine. The difference is often just the difference of contrast. Its best to give the least you can.

2) How interesting to find a V pattern exotropia. the head position chin up may not be anything, but does fit in with controling diplopia with a V exo pattern. This could point to an overaction of the IO muscles or possibly to a missalignment of the insertion of the LR or MR muscles.