OT skills guide: Jackson Cross Cylinder

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Күн бұрын

This video takes you through the technique and theory of using the Jackson Cross Cylinder to determine a patient’s astigmatism. This is used after determining the best vision sphere.
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Пікірлер: 32

@Mango037 4 ай бұрын

As a patient, this helps reduce the anxiety of choosing. It has helped me have better understanding on what is the purpose of this phase scientifically. I don’t have astigmatism but my child does. Thank you for sharing this valuable information. Now I look forward to our next Ophthalmology visit.

@otiebrown9999 Жыл бұрын

It is good to see the debate on the difficulties of measuring cylinder- accurately.

@camelCased 10 ай бұрын

Important bit when dealing with patients who have seriously impaired vision since birth (nystagmus, ocular albinism, such as myself). They might have a very weak ability to judge the specific direction of lines in the distance. So, for example, if a patient who has problems with distinguishing vertical lines clearly is being asked if the circle looks sharper with lens one or two, they might base their reply solely on the horizontal-ish parts of the circle. They will have a very hard time deciding if the circle has become rounder or not because the vertical parts will look blurry to them because of their nerve-brain issues, so no lens can fix those. This might make subjective refraction much more difficult when you know that the patient sometimes is confused and might start giving conflicting answers when it comes to dealing with correction at more vertical angles.

@astemet 11 ай бұрын

It was really useful to mee.. i was so confused about my degrees for cil

@tabelangbrendainbrendain4110 4 жыл бұрын

This really helped a lot we hope for many more videos

@nsr2839 Жыл бұрын

Hi , I have a doubt in +1 blur test , Is it not necessary that patient should read 6/18?

@Lapata511 11 ай бұрын

I don’t think so. It should be above four line

@rehmanakudi68 4 жыл бұрын

I don't think it's a good way of teaching JCC...we were taught a much better way by professor Barratt and Prof Elliott at Bradford uni...check his book out... Primary Eye Care. Not saying this is wrong...just over complicating what in essence is a pretty simple task.

@SharrpDesigns 3 жыл бұрын

Do you check cyl power first or cyl axis first? Which one do you start checking at the beginning.

@fahdhanif3046 3 жыл бұрын

@@SharrpDesigns cyl axis first usually

@ВоронМаусы 2 жыл бұрын

Do you leave the -0.25 (that you include for the JCC in the beginning) as part of the prescription, or do you remove it after the process is finished?

@vic-arenal7634 2 жыл бұрын

What if a patient did not report axis as equally clear but one to be clearer than the other, were by you will begin to go back and forth what axis should be used.

@francesko3640 Жыл бұрын

anna de armas

@bobjobjoe8887 4 жыл бұрын

6:10 \o/

@ugochinnamdi9275 7 ай бұрын

Could have been a great video but you were too fast. Thank you all the same

@CuriousDrifter 9 ай бұрын

The circle of least confusion was already placed on the retina at the end of the last video (best sphere) and verified by the duochrome test, why do we need to over minus the patient by -0,.25 before using JCC?

@MrGeriausias 7 ай бұрын

This helps to ensure that the circle is on a retina, because accommodation will bring the circle on retina

@d.perera7875 2 ай бұрын

@@MrGeriausias But doesn't the eye need to be at accommodation rest for the whole subjective refraction? Why don't we just leave the circle on the retina by best vision sphere?

@MrGeriausias 2 ай бұрын

@@d.perera7875 Once the cylinder is set, you will adjust the sphere again. You can refine the sphere using the +-0.25 technique. After that, you will move to the next eye.

@d.perera7875 2 ай бұрын

@@MrGeriausias Okay but why overminus at all? Isn't the circle of least confusion on the retina by the BVS? Why force the eye to accommodate?

@MrGeriausias Ай бұрын

@@d.perera7875 BVS should bring the CoLC on the retina. However, there is a chance that a patient made a mistake in deciding which sphere is clearer. If you are not 101% sure that the CoLC is on the retina, it is safer to over-minus myopes and under-plus hyperopes cause accommodation will bring the CoLC on the retina. Over-minus myopes and under-plus hyperopes is a harmless extra step that fulfills the CoLC requirement of JCC test.