In this presentation, Dr. Hayek discusses the CT Scan and MRI in orbital imaging. He presents a few cases and explains which scan is needed in each situation. He also discusses at length about thyroid eye disease, treatment plan and the use of steroids in future.
Lecture location: on-board the Orbis Flying Eye Hospital in Chittagong, Bangladesh
Lecturer: Dr. Brent Hayek, Emory University, Atlanta, USA
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Dr. Brent Hayek: So, I think it’s important to go over imaging. Again and again. And even for me, it’s helpful for me to keep reviewing imaging. Because there’s always these nuances I pick up. You know, the more I go over it. And so, we’ll kind of briefly go — we have a few minutes and we’ll kind of go — I have a lot of kind of case studies that are interesting to look at.
But, you know, in brief, these are some things about CT imaging. It does use radiation. It’s useful for evaluating most things in the orbit. That’s why it’s very common for us to get it. The bony anatomy is terrific. You don’t see that well on MRI. And so, for orbital surgeons, it’s very helpful to see the bony anatomy. IV contrast can be helpful for tumors and inflammation. Because things light up with inflammation. But beware of allergies to iodine and shellfish. So, these would be barriers for somebody that would need contrast. With the CT. And you can get axial and coronal cuts that can be very thin slices without repositioning the patient. Nowadays with reformatting technology, the patient does not have to be put in didn’t positions.
Bone is white, fat and air dark, and muscle gray. And we all know that. MRI. This is basically using large magnets, right? The resolution can be less than CT, but the tissue contrast is higher. And so, this is where it can be most helpful in looking at the apex and the cavernous signs. So, this is the deep orbit. I would also say for things in the optic nerve. So, optic nerve lesions can sometimes be better seen. Also, some vascular structures like varix and things like that can sometimes be very — the contrast is different. It uses gala di knee yum. And so allergies for shellfish do not matter in this case.
But the disadvantage is this mainly poor, bony view. It’s more expensive. It’s slower. Many times patients, they cannot have any metal in their body. And they cannot be really claustrophobic for most MRs because they’re kind of put into a tube.
Various imaging can be done. I don’t want to belabor the point. But one of the things is looking at T1 and T2. So, any time you see the eye ball white, you know that’s T2. There’s a 2 in H2O, water, and a 2 in T2. So, it’s bright. It’s good for edema and fluid. But the T1 gives you better anatomic detail.
In fact, there is now in the series you will see fat suppression. So, fat suppression T1 images will really give you the most excellent kind of detail, looking at them.
There are also other kind of special techniques in different types. So, angiography with CTA can be very helpful for some of the vascular issues that you’re looking at. Valsalva, like Dr. Kim talked about with the varix. Or patient in a prone position. Because many times you will not see a varix if someone is laying supine. Their eye may look ectopic. You will not see the mass but in a prone position. There is 3D reduction. Stereotactic for surgical guidance. MRA. Also for angiography, FIESTA, and other ways of looking at the seventh nerve in the posterior fossa.
We won’t really talk about orbital anatomy too much. But the orbit has seven bones. So, when is imaging warranted? Trauma. You know. Generally imaging is warranted in trauma. Not always. But if something clinically seems amiss, then imaging warranted. And that, you know, when we think of orbital trauma, we mainly think of fractures. What is the most common wall to be fractured? Is it the medial wall? The lateral wall? The roof? The floor? Yeah. So, it can be the floor or the medial wall. And generally that’s an orbital blowout fracture.
You know what the definition of an orbital blowout fracture is? It’s a fracture that you see a blowout, right? Of the medial or the floor or a combination, but the rim is spared. So, the thick bone of the rim you don’t see a fracture. You’ll see that more in a tripod or a zygomatic maxillary facial fractures, but you don’t see that in a blowout. So, that’s sort of the technical definition. Proptosis. Something has to be behind the eye. Whether it be something inflammatory like in Grave’s eye disease or a tumor. Orbital cellulitis. There you’re looking at, you know, to confirm it’s orbital cellulitis sometimes. Also looking for abscess formation. Because there are clinical scenarios where we will take the patient to the operating room and you’ll drain like a subperiosteal or an orbital abscess.
Congenital anomalies as well. Goals of imaging: Help with the diagnosis. You may not get the exact diagnosis, particularly in an orbital mass. You may need a pathological diagnosis to further assess that. And surgical planning. So, that’s very common in Grave’s eye disease. So, Grave’s eye disease, or thyroid eye disease, is mostly a clinical diagnosis. You should be able to make that clinically and not rely on imaging. There are occasions where it can be nebulous or hard to make that determination and imaging may be helpful because you look at the muscles — extra ocular muscles and fat. And you’ll see enlargement, generally in that spurious tendon in the extra ocular muscles. But it’s also helpful really in surgical planning. Because you want to know where the sinuses are positioned. You want to know where the cribriform plate is positioned. The skull base. You want to know if there is anything with the sinuses that you need to be aware of.
Sob imaging, just the basic things, tells you the location, surgical space, size of things, shape of things, adjacent tissue behavior. Things like that. So, this is a case here. This is a lady that was referred to me. And if you look at this slide, what stands out? You see a difference, right? This side looks in compared to this side. So, is this side proptotic, or is this side enophthalmic? That is sometimes a question you need to know. And typically the history will give you that. Not always. But typically it will.
And so, she’s an elderly Caucasian woman. And she’s 86 years old. And she had a double vision for a few months. And she had a history of prior lymphoma of her groin. Follicular cell lymphoma of her groin. And I think that as an important thing we talked about yesterday in patients where you may see a difference in their eyes and you’re suspecting an orbital process to just briefly ask, have you had a history of any kind of cancer before or any history of trauma? Any history of an inflammatory disorder? Common things being common, thyroid eye disease giving you proptosis. Ask about any problems with thyroid.
And on her scan, you see this. So, is this a CT or an MRI? That’s the first thing you ask yourself. Because people come in with scans. And you say, is this a CT — yeah, this is an MRI. And you look at it and you say, well, this is an axial. Now, is this a T1 or T2 MRI? T1. Exactly. Because you look at the vitreous to aqueous, you look at the ideas of the eye, it’s dark. In T2 you see it lighter. And do you see anything between these two eye sockets that’s a concern? And we’ll start off. You see in here,ing right?
You see this mass that’s overlying on the right side. So, if you look back at her clinical folio, you say — and here, again, this is in the area of what? The lacrimal grand. Right. So, the lacrimal gland is a common site for lymphoma. And we ended up biopsying the lacrimal gland and we found lymphoma. Generally lacrimal or any orbital lymphoma generally is not a surgical process. So, further surgical removal is generally not something that’s done. Typically it involves, then, what would be next? If you say, oh. I biopsied the patient’s lacrimal gland and they have lymphoma. Then what would you do? Radiation. Right. So, radiation may be what’s done next. But I would say the best next step would be to talk with your heme-onc doctor. The patient’s oncologist if they have an oncologies.
Because, what’s best is to do a systemic workup again. And the reason for that is, there may be other sites of lymphoma. And patients need to be restaged. Basically the staging is important for a lot of cancers because the stage helps determine the patient’s prognosis and really, what’s the best treatment. So, that may involve not radiation alone, or it may involve chemotherapy if there’s more to that.
This is an unusual case. But this is a rather classic look or appearance to this patient’s lesion that they have on their left upper lid. Yeah. It kind of looks like basal cell. Because kind of centered, these kind of rolled edges. The patient had a permanent eyelid tattoo. So, the black is just from their tattoo.
This was actually initially — I don’t know what it initially looked like. This is when the patient finally came to me. But they were diagnosed with — well, they thought it was a stye. So, the patient had the stye removed and then it came back. And then they had a removed again and then it came back. So, it ended up being a Merkel cell cancer. So, Merkel cell is a very rare cancer. But it tends to have violaceous, kind of a reddish look. And it’s one of the cancers that’s actually very rapidly growing. So, this had been almost — you know, much smaller, and then within a couple months it was this size. Where basal cell would be much slower growing in general. And Merkel cell is a rare, but can be fairly aggressive, cancer. And can metastasize and ultimately harm the patient.
And so, because of that, we wanted to image the orbit. Because I could palpate and felt like mostly it was in there. And so, we ended up getting a scan of the orbit. And you can see here some of the tumor. But you don’t see really anything in the orbit. This one slice won’t tell you everything. But she ended up not really having orbital involvement. So, this was confined to the eyelid. We didn’t feel like it went past the septum. She ended up having excision. She ended up having reconstruction. She ended up having radiation as well. Because that’s generally what’s done at the event is radiation.
One point to make is, any time someone comes in with a stye and you remove it and it reoccurs, the thought process is, you should maybe do a biopsy. Of any reoccurrence. Most of the time it will come back as a stye. Your biopsy. But what would happen is, we did a Cutler-Beard flap. She had radiation. And it really damaged the cornea. And her eye really had a hard time closing because the mobility of the flap and the radiation and the scarring that she underwent.
This is a patient that got shot with a BB gun. A small pellet gun. And we see this once every couple months. Someone’s out playing and someone shoots another person with the BB gun. You see — what do you see here? What is this black? Air, right? So, this is air.
It’s very common to see air in an orbital injury from trauma. What else do you see? Yeah. There’s something — there’s probably a small fracture that you don’t see in this view in the sinus. And there was. There was a small fracture in the sinus. And not all fractures can be repaired. It’s a good example for a couple points.
When would you repair, say, an orbital blowout fracture? There are some criteria for repairing orbital blowout fracture. What is one of the criteria for repairing orbital blowout fracture?
>> Restriction, or, is there any vision problem. Okay. Then the diplopia or the ocular restriction.
>> Where there is severe enopthalmos.
>> One other one. So, if there is persistent double vision. If there is significant enopthalmos. And we kind of describe that as greater than 2 milliliters. Right? So, either proptosis is 2 milliliters, or enopthalmos is 2 millimeters. There is a third one that’s commonly thought to be.
>> Cosmetic purpose?
>> Cosmetic purpose. Yes. That usually falls in line with enopthalmos. Because that’s usually something that someone would see. The last one would be, if it’s a large defect. So, greater than 50% of the floor or medial wall. Because they’re at risk — even if they don’t have enopthalmos at the time, over a longer period of time, months later, they will develop sometimes enopthalmos. And that’s called late onset enopthalmos. So, if they have persistent double vision, if they have enopthalmos, or if they have a large defect that is going to predispose them to developing enopthalmos, it’s better to fix it now rather than later.
Generally the time frame was thought to be around a couple weeks. No one seemed to know where that came from, you know? And there’s been recent publications and studies that show fracture repair at four weeks, six weeks. It’s just as fine as repairing it at two weeks time. People will repair sometimes these fractures right away. There’s a lot of soft tissue edema. There’s a lot of — that will give you double vision. So, if a patient has double vision right away or a day later, that may just did from the swelling. And it may not be because there is any entrapment of tissue.
Generally when you see entrapment of tissue, its the periorbita or the periosteum, it’s not usually the muscle. Muscle you are concerned about. That’s more in younger patients, right? Where they can kind of — their bones are like young trees where they don’t snap. They sort of tear or bend. And they can kind of get that blowout. The muscle gets stuck. The bone kind of goes back and the muscle comes. And they can — the risk is ischemia in those cases. But generally, do you see anything else? There’s one other thing that’s sort of hidden on this CT. What’s that? That’s the pellet. That’s the BB.
So, it’s very deep. Right? So, the question, then, became, should we remove this or not? Well, the patient, I’ll tell you, didn’t have any clinical problems. So, we decided to leave the BB. So, generally speaking, if it’s anterior and easy to get to, you would probably remove the BB. If the metal was causing any problem clinically, you would remove the pellet or fragment or BB. But if it’s deep into the orbit, and it’s not causing them a problem, generally people can tolerate metal in their body and you just leave it alone. So, we chose to leave this patient’s BB alone and they’ve done subsequently fine and not had any problem. Rarely will you see metal that migrates and causes a problem. So, some people would elect to say, well, let’s do a CT and several months down and we’ll just see and make sure that the metal has not migrated.
This is another example of trauma. What do you see? This is a nail from a nail gun. The patient was nailing and got a piece of metal and if went through their eye. And the patient, being a trauma patient, happened to have a CT scan just to rule out any other injuries. And because sometimes you do not know the length of the nail. You know? Fragments can be all different sizes. Or maybe they had two nails, or three nails and sometimes we have seen that as well.
And this nail went from the anterior aspect of the eye through to the posterior globe and then it stopped. So, they didn’t develop any orbital problem. The patient was then taken to the operating room. The nail was removed, the cornea was sown and they did okay. They had cataract surgery, but they didn’t have any further surgery done because it went through the lens. We have a retina service. They came in. They examined the patient. They followed the patient for a while. And they, fortunately, did not — that’s a very good point to make because many of these injuries ultimately can result in a retina problem like a tear and such.
And that’s the nail. She had complaint of right-sided double vision. She had no other medical problems in terms of inflammatory conditions. That being thyroid, that being idiopathic inflammations that you would suspect as a diagnosis of exclusion. Any sarcoid, things such as that. But she had developed a restriction of the eye. Sometimes imaging can be important in her case. And she had a significant cancer history. Thyroid cancer, breast cancer, renal — and she had a little bit of proptosis in the right eye. So, we got the imaging study.
So, this is a medial rectus mass that is in the center anterior aspect of the medial rectus. Based upon more imaging. Or right next to the medial rectus. And we went and we did a biopsy. Able to fully excise it. This is a transcaruncular approach. So right through the caruncle, or right adjacent to the posterior aspect of the caruncle, we can get to the extra coronal space, we can get to the medial rectus. We can get to where the mass is and we removed it. And this is approximately a 1 centimeter mass. It’s red and vascular. It was renal cell carcinoma which is pretty rare to the orbit.
This is a lady who suffered extensive trauma. She was beaten by her maid and money stolen. It can be helpful in some of these — this is an example of a 3D reconstruction. And so, on the 3D reconstruction, she’s — you can see she’s already had many surgeries in the past. These are all plates, right? For fixing of the fracture. She was beat with a hammer. And she almost died.
And you can still see some displacement. So, it can be very helpful in surgical planning looking at all the bony work. Because if you look back at her photo, you can see the zygomatic process, her cheek is more anterior. This is a more flattened cheek. The bone — there’s some cavity, loss of temporalis, more temporalis fossa. There’s a lot going on.
The eye implant looks lower so she has this hypoglobus. And that goes along with some of — it’s hard to see totally — but it goes along with some of the depression in the inferior aspect. So, I did some of the work and had some of my facial plastic colleagues do some of her other reconstruction to help make her better.
But I told her it’ll never look the same. You know, we can help in some aspect, but I think that’s also important that it’s very difficult to make someone really normal fully again.
This is a 34-year-old woman that came into our clinic with a left upper lid swelling for a year’s time. She had no double vision, no complaint of vision loss. And she didn’t really have any proptosis. But she has this left upper lid swelling. And you look at the eyelid and you see this sort of S-shaped curve, right? And so, your suspicion — and the eye looks like it’s not only being — it’s being pushed down, right? And being pushed in. So, what would be opposite of that? The lacrimal gland, right? So, this is a, you know, a way of looking and assessing and say, well, I suspect something is in the superior orbit. It looks like mainly maybe the superior lateral orbit. I know the lacrimal gland is there.
So, this is a CT scan. And you see the lacrimal gland on the opposite side and then you look at that. There’s a very large lacrimal gland. And this scan is not the highest quality. But you can see a fairly well-defined lesion. And in lacrimal glands, you always especially want to look at the bone. I think it’s always important to look at the bone as well. You don’t see really erosions in the bone or the bone being very involved. So, I suspect that, if it’s a lacrimal gland tumor, it’s a more benign tumor, or if it’s a lymphoma, a molding — but that tends to be more molding rather than something that’s pushing the eye so much like this.
We did an excisional biopsy, and that was a pleomorphic adenoma, a benign mixed tumor. A lady with breast cancer. And she was developing double vision. And with a significant history of breast cancer. It was important to image her. We imaged her. And what do you see? Left orbit, yes. Yes. Right here in her lateral rectus muscle. She had horizontal diplopia. Breast cancer, it went align. She also, after reviewing and talking with her oncologist, had other sites of metastatic breast cancer. So, this was presumed to be breast cancer. Like we talked about yesterday, many times, if you want radiation oncology to help you and radiate, they want to know from the tissue.
Sometimes day don’t need that. If they agree to radiate the orbit, which she underwent. Because there’s — it’s known. It’s presumed. This is a 42-year-old in a motor vehicle accident. And unfortunately he ruptured his left eye. But you don’t see the eye because we’re behind the eye, right? This is a CT. Coronal cuts. And what do you see? Floor fracture.
Yes, this is a classic floor a fracture. And do you think it was entrapped? I would argue, no. Because you see the bone displaced way out here and you see the inferior rectus mostly right here. So, I don’t see bone really impinging that. I would also say that we — it’s a clinical diagnosis more than a radiographic diagnosis. So, the patient really cannot look up. They have changes in their pressure, changes in their blood pressure. That’s telling you that, yes, the muscle is entrapped. But this patient also had a there are fracture with the ruptured globe.
This is a young child I believe around 6, 7 years of age that was developing new onset proptosis. So, in a child, say, 8, 9 years of age developing new proptosis, what’s the most concerning type of orbital mass? This is a cancer. What’s the most common primary orbital cancer in a child? Rhabdomyosarcoma. Yeah. So, we are concerned about rhabdomyosarcoma. So, this warranted a biopsy and it ended up being rhabdomyelosarcoma. And then he underwent further treatment, including chemotherapy. And because it wasn’t grossly fully excised, radiation as well.
And this just shows you the approach. And you can see the tumor right here. This is a gentleman who had a gradual history of proptosis and double vision. No real pain over months. Maybe a year’s time. And which side is abnormal, do you think? Left side, yes. Hypoglobus. The eye is being pushed down. And so, you suspect inferior? Superior? Superior, yes.
So, we got an imaging scan. And this is his imaging scan. And I’ll tell you, it can be hard to see from just one scan. Looked like it involved a lacrimal gland to us. You can see the sort of normal lacrimal gland on this side. You see the lacrimal gland. Do you think this is a molding lesion like in a lymphoma of the lacrimal gland? An aggressive lesion like an adenoid cystic carcinoma of the lacrimal gland? Or more of a benign mixed tumor lesion? Those are your three choices. Carcinoma.
So, we’re looking at the bone. Look at the rim here. And this one looks like there’s some maybe remottling without erosions to it. So, we were thinking maybe more of a pleomorphic adenoma. And not a lymphoma, because look it. It is really pushing the eye. Usually lymphoma will mold more. So, he had — would this be best, do you think, with a frontal or anterior orbitotomy, or a lateral orbitotomy?
A lateral orbitotomy. That was our choice as well. So, we went and we did a lateral orbitotomy and this came back. I’ll show you the coronal. This is his coronal scan. Showing you the superior lateral orbital lesion involving the lacrimal gland. And this was a pleomorphic adenoma that we were able to fully excise.
This was a young gentleman that came to our clinic that was also shot with a BB gun. And to his eye area. He had no vision complaint. He had a full eye exam, which was normal. He had no double vision. It’s sort of apparent what you see there. It’s a very bright material. Consistent with the BB. And we elected to remove the BB. So, because this one was also deep in the orbit, we elected to just reimage him in six months. Some of the reasons why we take out metal — sometimes in young, or even older people — they may need an MRI or an unrelated reason. Like a back problem. Or, you know, shoulder or some sort of problem. So, sometimes what we do is we — if we can take out the metal, then they’re safe to have an MRI years later if they have another problem and they need an MRI for some reason.
And sometimes they’re sent to us because they found metal and the doctor wants to do an MRI of their shoulder, but because they have metal around their eye, they say, can you take this out so the patient can get an MRI? There’s actually another reason to take out metal like a BB is because they may need an MRI in the future. So, where MRI is more common.
This is a CT or an MRI? MRI. Yes. And what do you see? Which side seems abnormal? Which muscle looks abnormal? Yes. It’s enlarged. And this patient had an enlarged muscle. And what’s the more — most common reason they would have — thyroid eye disease. Yeah. So, this patient just had a history of thyroid eye disease. I don’t remember the reasons why they had the scan, but they had a history of thyroid eye disease. And I think that the doctor wanted to make sure that their vision was okay. They didn’t have crowding around the apex, which they did not. Because these muscles are very normal appearing. This is a CT scan. What do you see here?
What disease do you think this patience has? What condition? Thyroid eye disease. Yep. Same thing. What’s the most common muscle involved in thyroid eye disease? Inferior rectus. Inferior rectus, then usually medial rectus, superior, lateral, then obliques. It can be any muscle, though. So, if someone comes in with just superior oblique, I mean, say, superior rectus enlargement and they have other signs of thyroid eye disease, lid retraction, and you happen to have imaging and they just have that muscle, that’s thyroid eye disease. So, this is the most common presentation and I don’t have an image to show you, but further back there was a lot of crowding and the patient was losing some vision, had an afferent pupillary defect. Had some small vision field loss on a visual field. So, they had compressive optic neuropathy. And we took them to the operating room and we decompressed this bone here and their vision came back.
What do you see here? So, the right eye looks enophthalmic. There are some clues to that. You look at the superior sulcus. And you see that there’s the loss of that prominence that patient should have. Are the eyes level? Or no? This one’s higher than this one. So, this eye is lower. So, we call that hypoglobus. So, they’re in — they’re enophthalmic, they have hypoglobus, and they have this superior sulcus defect.
So, this patient had developed this over a period of months, a year or so. And finally came to the clinic and said, look, I have this process going on. No pain, no other symptoms. Just something that they noticed. So, we got an imaging study. And what do you see here? There’s something in the maxillary sinus. What about the floor? Is it broken? This is a more rare condition. So, the floor is very thin. There was no trauma. I would argue that the bone is there. It’s just being pulled down. Do you know what condition this is?
This is called silent sinus syndrome. So, there is a negative vacuum being created in the maxillary sinus based upon the outflow problem from the sinus cavity. And it’s just pulling things down. And it’s shrinking in size. And so, the treatment is to open up that size, allow that. And then you usually can either wait or repair the floor if it doesn’t go back up. And that fixes the problem. So, it’s a combination of a sinus surgery and then perhaps as well an orbital surgery. Sometimes it’s needed, sometimes it’s not.
This is a 6-year-old boy who was playing and hit with a golf club. Do you see sign of trauma? There’s a scar. So, you always want to kind of look and you want to feel as well as know the clinical history. So, he was hit with a golf club and it’s also important to always rule out a head injury. Any type of head injury, head trauma. Ask about loss of consciousness, ask about any kind of head trauma. And so, what do you see here? Do you see the sort of roof, right? The roof of the eye, right? So, a roof fracture is not a very common fracture, but it’s more common in kids.
They kind of pull things down and things fall on them because they’re very — they’re little people. And they can get the roof fracture. So, this is just to show a sagittal image. So, sometimes a sagittal cut can be help to feel look. And you see that bone fragment displaced. And he was sent because they knew he had a roof fracture. His eye was okay. He did not have any globe injury. But he had this and they were concerned about the bone fragment and the roof fracture.
So, looking at another image, sagittal cuts can help you look and say, the roof had a fracture anterior, but the rest of that in the brain, that was okay. So, we elected not to do anything. The bone was reabsorbed. He did not have any motility problem or complaint of pain by moving his eye. So, he left that alone.
It’s important to know when to order and how to evaluate the CT or MRI. Trauma, non-contrast CT is the modality of choice. And it’s usually a CT of the head. Because the brain is a very important organ. They’re always looking at that. New onset proptosis. It’s very hard to know what’s behind the eye, but someone has new onset bulging of the eye, and they don’t have a clear history of, like, thyroid eye disease, ordering a CT is very, very, very useful.
Axial and coronal imaging is best to characterize some of these fractures and these lesions. So when you order an orbital head CT — I mean, an orbit CT — you will get these cuts. Know when to get a CT for thyroid eye disease. It’s not something, as we mentioned before, that you need to order on every thyroid eye disease patient. Most of them are mild. But if someone is complaining of vision loss and they have moderate or severe signs of thyroid eye disease, or you’re concerned that they have compressive optic neuropathy, then that can be helpful to look at the apex of the orbit. It helps mainly in surgical planning. Knowing what bone you’re going to remove for decompress if that’s your proposed plan, or any atypical presentation is made clear.
And then, be familiar with these special studies. Someone needs Valsalva with a varix, MRV for some — or CTV for a vascular venous malformations. I showed you an example of a 3D for more multi-involved reconstruction. And then stereotaxis can be useful for lesions within anatomy.
Ultrasound can be useful for posterior globe in anterior orbit. You can’t see beyond much with ultrasound in the mid or posterior orbit. So, ultrasound is usually more available in an ophthalmology clinic because they use it for other eye conditions, right? And there are characteristics, whether it’s an A or a B scan, that can help tell you what’s going on. But the scan is better than nothing. It’s not nearly as good as CT scan. But if you had that, and you suspect something is in the anterior orbit, or even you are not sure, it’s helpful to at least try and to see. Because you may get some diagnostic criteria out of that. At least knowing the position, maybe the size of something.
But we don’t find it that useful in our clinical practice. And because CT is so widely available, we generally just send the patient for CT scan. But it can be helpful. Particularly if CT’s not available.
So, what is the role of steroid indication in thyroid eye disease? That’s a good question. So, I would argue to say, we don’t fully understand thyroid eye disease and the immune mechanisms yet for it. And we really do not have an approved therapy for it. And if you look at the literature on use of all sorts of drugs and the top ones are steroid and that would be either IV or PO steroids. So, systemic steroid, or radiation. And then there are a lot of other things, Rituximab, new emerging tocilizumab, teprotumumab. It can be helpful. And I would say that, in our clinical practice, steroids block all inflammation, right? So, you give someone oral steroids or IV steroids and it can significantly reduce their inflammation.
So, most people would go by either a classification system, like the visa or the EUGOGO for measuring the activity or the cast for thyroid and if they’re considered moderate or severe, then generally they’ll be put on IV or PO steroids. And IV is probably better and maybe a little safer than PO steroids. But steroids have risks. They have significant side effects. Especially long-term use of steroids. And you have to be careful in some populations, like diabetic patients, because insulin, blood pressure, insomnia, bones, things like that.
So, I generally reserve them for patients that are kind of moderate or severe, and we may try a course of steroids with the knowledge that it may not change the ultimate course of their disease. They may get rebound inflammation. And I also will use it as a temporizing effect for compressive optic neuropathy before a more definitive approach either by radiation or by surgical decompression. So, most cases of thyroid eye disease are mild. And even though it’s in the patient’s mind that it’s more severe than what you see, I would hold off and not give steroids. And more hold their hand through the process.
Because ultimately as you know, thyroid eye disease has this active state and then it has this enactive state. And they will go through that over a six to 18-month, two-year period. Smokers, longer. So, encouraging not smoking will help if they do smoke. But they ultimately will burn out. So, if you can help them through that process, then, yes.
The — what we would like to be — like, is to have a drug that can arrest or minimize the amount of damage that occurs during that active phase. Particularly for the moderate to severe cases. And so, there is a drug called teprotumumab. So, it’s a biologic, it’s an antibody — a monoclonal antibody that’s directed against the insulin-like growth factor receptor one that is thought to be coupled with the TSH receptor in this kind of cascade of all of the inflammatory process that you see.
And there is a good article in the “New England Journal of Medicine” that came out last year. It was a multi-center trial, a phase two trial. And done in the U.S. and Europe. And it showed probably some of the best clinical response than has been reported elsewhere. Not only in decreasing the activity scale, but even the proptosis. So, steroids and radiation and — they don’t necessarily help with that. But this drug has. And there will be, I think, more targeted therapies in the future.
This drug is going through phase three trial right now and it will probably be available in Europe in the next six months and other places like the U.S. a year or so later. But I think finding the right target for many of these things, including cancer inflammatory processes, is the key. But so, steroids can be helpful, but I would reserve them for moderate or severe cases. And then ultimately understand that they may not help with everything.
Sometimes I will also give an intraorbital injection of steroid. So, that has been helpful in a select population of patients that are intolerable to the side effects of systemic steroids. So, they have some moderate or some severe inflammation. I will take triamcinolone, 40 milligrams per mil. And I will take a cc and I will inject it like on a retrobulbar needle into the orbit. That also has some risks to it. There is a chance of increasing the pressure with like any steroid.
So, it may be visible to — if that was a consideration — have them on systemic steroid or topical steroid just to see if they have a response. And, you know, if a few weeks go by, there’s no increase in intraocular pressure, that may be the safest choice. Because, right. Once I depo that steroid, I can not reverse that. That’s why I have been reluctant to use it in the populations that I’ve had. I have not seen anyone get an increase in intraocular pressure, but you’re correct. That can happen.
There is also people that have been trying, experimenting, with Tocilizumab. Tocilizumab is approved for other inflammatory. It may be rheumatoid arthritis or something else. So, it’s available. So, many times once a drug is approved for one condition, as a physician, then, you can get access and you can use it in other areas. You know, you want to be careful, obviously, with doing that. But teprotumumab is not currently available. It will be available probably in Europe in about six months or longer is what I’m told by one of the head scientists. And that, I think, is probably the most promising thing we have that will be coming out.
January 8, 2017