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Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:02.73,Default,,0000,0000,0000,,All right, next topic:\Nocular misalignment.
Dialogue: 0,0:00:02.73,0:00:05.67,Default,,0000,0000,0000,,If the eyes aren't aligned properly,
Dialogue: 0,0:00:05.67,0:00:08.58,Default,,0000,0000,0000,,then you might have an exodeviation;
Dialogue: 0,0:00:08.58,0:00:09.99,Default,,0000,0000,0000,,exo just means outwards,
Dialogue: 0,0:00:09.99,0:00:12.48,Default,,0000,0000,0000,,or an esodeviation, that's inwards.
Dialogue: 0,0:00:12.48,0:00:15.96,Default,,0000,0000,0000,,There's also a hyper and a hypo:\Nup and down.
Dialogue: 0,0:00:15.96,0:00:18.39,Default,,0000,0000,0000,,So let's give a couple examples of this.
Dialogue: 0,0:00:18.39,0:00:20.28,Default,,0000,0000,0000,,Let's say you have normal eyes,\Nand one of the ways
Dialogue: 0,0:00:20.28,0:00:22.98,Default,,0000,0000,0000,,you can actually estimate\Nif a young child
Dialogue: 0,0:00:22.98,0:00:25.29,Default,,0000,0000,0000,,has an eye that's turning in\Nor turning out,
Dialogue: 0,0:00:25.29,0:00:27.33,Default,,0000,0000,0000,,is by using the Hirschberg test.
Dialogue: 0,0:00:27.33,0:00:29.88,Default,,0000,0000,0000,,The idea is you shine a light\Nat the eyes,
Dialogue: 0,0:00:29.88,0:00:31.68,Default,,0000,0000,0000,,and you look at the light reflex,
Dialogue: 0,0:00:31.68,0:00:35.37,Default,,0000,0000,0000,,the corneal reflex of that light\Nbouncing off the eye,
Dialogue: 0,0:00:35.37,0:00:38.61,Default,,0000,0000,0000,,and you compare its position\Nto the underlying pupil,
Dialogue: 0,0:00:38.61,0:00:40.38,Default,,0000,0000,0000,,and normally that reflex ought to be
Dialogue: 0,0:00:40.38,0:00:43.44,Default,,0000,0000,0000,,laying right on top of that pupil.
Dialogue: 0,0:00:43.44,0:00:45.78,Default,,0000,0000,0000,,However, if you have one eye\Nthat's deviated,
Dialogue: 0,0:00:45.78,0:00:47.100,Default,,0000,0000,0000,,for example, this left eye\Nis turned inwards,
Dialogue: 0,0:00:48.00,0:00:51.60,Default,,0000,0000,0000,,it's a left esotropia, then you can see
Dialogue: 0,0:00:51.60,0:00:53.73,Default,,0000,0000,0000,,that the light reflex is not quite over
Dialogue: 0,0:00:53.73,0:00:55.62,Default,,0000,0000,0000,,the pupil like it's supposed to be.
Dialogue: 0,0:00:55.62,0:00:58.17,Default,,0000,0000,0000,,In this case, the right hypertropia,
Dialogue: 0,0:00:58.17,0:01:02.31,Default,,0000,0000,0000,,the right eye is up a little bit,
Dialogue: 0,0:01:02.31,0:01:05.31,Default,,0000,0000,0000,,and you can actually estimate\Nthe amount of deviation;
Dialogue: 0,0:01:05.31,0:01:07.50,Default,,0000,0000,0000,,and the rule is for every millimeter
Dialogue: 0,0:01:07.50,0:01:09.87,Default,,0000,0000,0000,,that this light is off center,\Nso in this case,
Dialogue: 0,0:01:09.87,0:01:13.89,Default,,0000,0000,0000,,if this was one millimeter\Noff of the pupil,
Dialogue: 0,0:01:13.89,0:01:18.09,Default,,0000,0000,0000,,equals about seven degrees\Nin misalignment, or 15 prism diopters;
Dialogue: 0,0:01:18.09,0:01:20.13,Default,,0000,0000,0000,,and this is the measurement\Nthat we actually use
Dialogue: 0,0:01:20.13,0:01:22.17,Default,,0000,0000,0000,,in clinic, prism diopters.
Dialogue: 0,0:01:22.17,0:01:23.88,Default,,0000,0000,0000,,So we'll go over prisms in a second,
Dialogue: 0,0:01:23.88,0:01:27.81,Default,,0000,0000,0000,,but the Herschberg test, very useful.
Dialogue: 0,0:01:27.81,0:01:30.42,Default,,0000,0000,0000,,Now, we just talked about eso/exo,
Dialogue: 0,0:01:30.42,0:01:32.28,Default,,0000,0000,0000,,tropia/phoria, what does that mean?
Dialogue: 0,0:01:32.28,0:01:35.07,Default,,0000,0000,0000,,Well, tropia is when the eyes\Nare always deviated.
Dialogue: 0,0:01:35.07,0:01:37.77,Default,,0000,0000,0000,,So, if you have an exotropia,\Nthat means that the eyes
Dialogue: 0,0:01:37.77,0:01:42.57,Default,,0000,0000,0000,,are deviated out, they're wall-eyed\Nand they're always deviated.
Dialogue: 0,0:01:42.57,0:01:44.19,Default,,0000,0000,0000,,Now phoria, on the other hand,
Dialogue: 0,0:01:44.19,0:01:47.73,Default,,0000,0000,0000,,just means that they're only deviated\Nsometimes.
Dialogue: 0,0:01:47.73,0:01:50.79,Default,,0000,0000,0000,,So, example of a tropia
Dialogue: 0,0:01:50.79,0:01:52.89,Default,,0000,0000,0000,,would be exotropia or esotropia,
Dialogue: 0,0:01:52.89,0:01:54.78,Default,,0000,0000,0000,,and of course, the hyper and hypo.
Dialogue: 0,0:01:54.78,0:01:56.07,Default,,0000,0000,0000,,And of course, of the phorias,
Dialogue: 0,0:01:56.07,0:01:58.59,Default,,0000,0000,0000,,we would call it something like\Nan exophoria,
Dialogue: 0,0:01:58.59,0:02:00.63,Default,,0000,0000,0000,,an esophoria, etc, etc.
Dialogue: 0,0:02:00.63,0:02:03.39,Default,,0000,0000,0000,,So let's show an example of this:\Nthis eye,
Dialogue: 0,0:02:03.39,0:02:05.52,Default,,0000,0000,0000,,looks like this left eye\Nis deviated outwards,
Dialogue: 0,0:02:05.52,0:02:07.41,Default,,0000,0000,0000,,and we use our paddle to cover the eye;
Dialogue: 0,0:02:07.41,0:02:09.15,Default,,0000,0000,0000,,this is called the cover uncover test,
Dialogue: 0,0:02:09.15,0:02:11.37,Default,,0000,0000,0000,,and you look for this eye movement,\Nand that tells you
Dialogue: 0,0:02:11.37,0:02:12.45,Default,,0000,0000,0000,,that it's there all the time.
Dialogue: 0,0:02:12.45,0:02:14.61,Default,,0000,0000,0000,,So no eye movement here,
Dialogue: 0,0:02:14.61,0:02:16.86,Default,,0000,0000,0000,,because it looks like the right eye\Nis the dominant eye,
Dialogue: 0,0:02:16.86,0:02:19.62,Default,,0000,0000,0000,,this is a left exotropia.
Dialogue: 0,0:02:19.62,0:02:21.21,Default,,0000,0000,0000,,So let's try to correct it,\Nand to do that,
Dialogue: 0,0:02:21.21,0:02:24.54,Default,,0000,0000,0000,,we use prisms to try to get things\Nback in alignment.
Dialogue: 0,0:02:24.54,0:02:27.27,Default,,0000,0000,0000,,Things are still moving, so this isn't\Nquite enough prism
Dialogue: 0,0:02:27.27,0:02:29.49,Default,,0000,0000,0000,,to get things back in alignment.
Dialogue: 0,0:02:29.49,0:02:32.19,Default,,0000,0000,0000,,Let's try 20 diopters, and now,
Dialogue: 0,0:02:32.19,0:02:34.47,Default,,0000,0000,0000,,when you do our cover uncover test,
Dialogue: 0,0:02:34.47,0:02:36.69,Default,,0000,0000,0000,,we can see that things\Nare back in alignment.
Dialogue: 0,0:02:36.69,0:02:41.79,Default,,0000,0000,0000,,This was a left exotropia,\Napproximately 20 degrees,
Dialogue: 0,0:02:41.79,0:02:45.39,Default,,0000,0000,0000,,20 prism diopters, that is,\Nand you pick the tropias up
Dialogue: 0,0:02:45.39,0:02:48.63,Default,,0000,0000,0000,,with the cover uncover test,\Nwhich is what we just did.
Dialogue: 0,0:02:48.63,0:02:49.98,Default,,0000,0000,0000,,So let's try this one.
Dialogue: 0,0:02:49.98,0:02:52.95,Default,,0000,0000,0000,,These eyes look like they're\Nin reasonably good alignment.
Dialogue: 0,0:02:52.95,0:02:55.92,Default,,0000,0000,0000,,So let's do our cover uncover test.\NNo movement.
Dialogue: 0,0:02:55.92,0:02:57.93,Default,,0000,0000,0000,,Things are still nice and stable.
Dialogue: 0,0:02:57.93,0:03:00.93,Default,,0000,0000,0000,,Let's try the other eye; cover, uncover.
Dialogue: 0,0:03:00.93,0:03:04.14,Default,,0000,0000,0000,,Things are still in perfect alignment,\Nwonderful.
Dialogue: 0,0:03:04.14,0:03:06.81,Default,,0000,0000,0000,,But watch this: we'll do a cover
Dialogue: 0,0:03:06.81,0:03:08.82,Default,,0000,0000,0000,,and we'll do a cross cover test,\Nlook at that eye move--
Dialogue: 0,0:03:08.82,0:03:12.03,Default,,0000,0000,0000,,Oh, it's moving again-- Oh, that one's\Nmoving.
Dialogue: 0,0:03:12.03,0:03:13.62,Default,,0000,0000,0000,,This is what we call phoria,
Dialogue: 0,0:03:13.62,0:03:17.16,Default,,0000,0000,0000,,it's there some of the time,\Nbasically when we break fusion.
Dialogue: 0,0:03:17.16,0:03:19.32,Default,,0000,0000,0000,,Let's see if we can get rid\Nof this for you.
Dialogue: 0,0:03:19.32,0:03:23.73,Default,,0000,0000,0000,,Yep, about 10 diopters a prism\Nis all it took to fix this phoria.
Dialogue: 0,0:03:23.73,0:03:26.22,Default,,0000,0000,0000,,So this was an exophoria.
Dialogue: 0,0:03:26.22,0:03:28.05,Default,,0000,0000,0000,,It's there only some of the time,
Dialogue: 0,0:03:28.05,0:03:32.10,Default,,0000,0000,0000,,and there was about 10 prism diopters\Nof it.
Dialogue: 0,0:03:32.10,0:03:34.62,Default,,0000,0000,0000,,You pick up phorias with\Nthe cross cover test,
Dialogue: 0,0:03:34.62,0:03:37.92,Default,,0000,0000,0000,,completely different than\Nthe cover uncover test.
Dialogue: 0,0:03:37.92,0:03:39.21,Default,,0000,0000,0000,,Okay.
Dialogue: 0,0:03:39.21,0:03:42.03,Default,,0000,0000,0000,,So this is a loose prism,
Dialogue: 0,0:03:42.03,0:03:45.45,Default,,0000,0000,0000,,and certainly with kids, loose prisms\Nare the way to go.
Dialogue: 0,0:03:45.45,0:03:47.19,Default,,0000,0000,0000,,They also make prism bars,
Dialogue: 0,0:03:47.19,0:03:49.56,Default,,0000,0000,0000,,basically put a bunch of prisms\Nin a single bar,
Dialogue: 0,0:03:49.56,0:03:51.60,Default,,0000,0000,0000,,and you just dial this thing up and down
Dialogue: 0,0:03:51.60,0:03:54.39,Default,,0000,0000,0000,,till you find the right amount\Nof prism to correct.
Dialogue: 0,0:03:54.39,0:03:58.02,Default,,0000,0000,0000,,I personally hate these bars,\NI like to use the loose lens prisms,
Dialogue: 0,0:03:58.02,0:04:00.90,Default,,0000,0000,0000,,they're a lot easier to use;\Nmy own personal preference.
Dialogue: 0,0:04:00.90,0:04:02.88,Default,,0000,0000,0000,,Certainly with children, you want to use
Dialogue: 0,0:04:02.88,0:04:04.98,Default,,0000,0000,0000,,the loose lenses\Nbecause they're smaller.
Dialogue: 0,0:04:04.98,0:04:06.93,Default,,0000,0000,0000,,If you use something this big,\Nkid's gonna try to grab it,
Dialogue: 0,0:04:06.93,0:04:09.36,Default,,0000,0000,0000,,it's not gonna work well.
Dialogue: 0,0:04:09.36,0:04:12.87,Default,,0000,0000,0000,,And if you have a tropia\Nthat can't be corrected
Dialogue: 0,0:04:12.87,0:04:15.33,Default,,0000,0000,0000,,by correcting with glasses or patching,
Dialogue: 0,0:04:15.33,0:04:18.18,Default,,0000,0000,0000,,then you can always go to surgery;
Dialogue: 0,0:04:18.18,0:04:20.40,Default,,0000,0000,0000,,And basically, when we have eyes\Nout of alignment,
Dialogue: 0,0:04:20.40,0:04:22.02,Default,,0000,0000,0000,,we get them back in alignment,
Dialogue: 0,0:04:22.02,0:04:23.73,Default,,0000,0000,0000,,and we do that by either shortening
Dialogue: 0,0:04:23.73,0:04:25.98,Default,,0000,0000,0000,,or lengthening the rectus muscles.
Dialogue: 0,0:04:25.98,0:04:28.59,Default,,0000,0000,0000,,In this case, this rectus muscle\Nis cut off
Dialogue: 0,0:04:28.59,0:04:31.11,Default,,0000,0000,0000,,from its insertion and it's reinserted
Dialogue: 0,0:04:31.11,0:04:35.85,Default,,0000,0000,0000,,back onto the sclera using suture,\Nand this basically lengthens
Dialogue: 0,0:04:35.85,0:04:38.94,Default,,0000,0000,0000,,the effective length of this muscle\Nand gets things back in alignment.
Dialogue: 0,0:04:38.94,0:04:40.92,Default,,0000,0000,0000,,And you can do the opposite,\Nyou can also shorten the muscle
Dialogue: 0,0:04:40.92,0:04:44.40,Default,,0000,0000,0000,,and reattach it back to\Nits original insertion.
Dialogue: 0,0:04:44.40,0:04:46.44,Default,,0000,0000,0000,,Not an easy surgery to do,\Nbecause you. could imagine,
Dialogue: 0,0:04:46.44,0:04:49.11,Default,,0000,0000,0000,,you're trying to do a scleral pass here
Dialogue: 0,0:04:49.11,0:04:51.54,Default,,0000,0000,0000,,and not perforate into the eye\Nand hit the retina,
Dialogue: 0,0:04:51.54,0:04:54.78,Default,,0000,0000,0000,,and the sclera is very, very thin.
Dialogue: 0,0:04:54.78,0:04:57.93,Default,,0000,0000,0000,,I mean, so thin. We're talking about\Na third of a millimeter
Dialogue: 0,0:04:57.93,0:05:00.24,Default,,0000,0000,0000,,right underneath this muscle insertion.
Dialogue: 0,0:05:00.24,0:05:02.43,Default,,0000,0000,0000,,You can very easily perforate\Ninto the eye,
Dialogue: 0,0:05:02.43,0:05:05.97,Default,,0000,0000,0000,,and not an easy surgery,\Nbut very effective.
Dialogue: 0,0:05:06.89,0:05:12.12,Default,,0000,0000,0000,,So that was ocular misalignment.\NLet's move on.