The patient has drooping eyelids for 1 year and has positive acetylcholine receptor antibodies. What disease can you think of?

"Dr.
Diaosi Wang Xiaopeng" series of novels have a lot of professional knowledge, each chapter is a case, there are difficult cases, and there are ordinary cases
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The purpose of this book is to hope that you can read leisurely and relax after busy work.
If you can inspire your profession, it will be great
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Author: Wang Mingyue This article is published by Yimaitong authorized by the author, please do not reprint without authorization
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Chapter 22: Confusing Acetylcholine Receptor Antibodies With time in the clinic, the more you can realize the importance of anatomy
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For example, Xiaobai, who is new to the Department of Neurology, has difficulty remembering the clinical features of orbital apex syndrome, superior orbital fissure syndrome, and cavernous sinus syndrome
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The reason is that they are not familiar with the anatomical structure of the orbital apex, superior orbital fissure, and cavernous sinus, in other words, they are not familiar with the anatomical structure of the skull base
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 The anatomical structure of the skull base is the content of the freshman year.
Let's start with the basics and review it again
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 The cranial nerves passing through the foramen cleft from front to back of the skull base are: optic canal (optical nerve) superior orbital fissure (oculomotor nerve, trochlear nerve, abducens nerve, first branch of trigeminal nerve) circular foramen (second branch of trigeminal nerve) ) Foramen ovale (third branch of the trigeminal nerve) rupture hole (carotid artery and sympathetic chain) petrous tip (trigeminal nerve and semilunar ganglion) inner ear port (acoustic nerve and facial nerve) jugular foramen (glossopharyngeal, vagus, accessory nerve) tongue Inferior neural tube (hypoglossal nerve) The lateral wall of the cavernous sinus is composed of the oculomotor nerve, the trochlear nerve, the first branch of the trigeminal nerve, the internal carotid artery, and the abducens nerve walking in the sinus from top to bottom
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Let's talk less gossip and start today's case
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 One day, Bai Jiao’s outpatient clinic went to a middle-aged male patient with a droopy right eyelid.
The course of the disease was 1 year.
Myasthenia gravis had been diagnosed in the outside hospital.
Physical examination: Drooping right eyelid, fixed right eyeball, bilateral pupils of equal size , Sensitive to light reflection, suspicious fatigue test, no abnormalities in the rest of the nervous system, no abnormalities in head MRI, no abnormalities in thymus CT, AchR(+)
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 The patient’s clinical symptoms are typical, and the fatigue test is suspicious.
AchR-Ab(+), Bai Jiao is proposed to be ophthalmic myasthenia gravis, he is admitted to the hospital, the RNS examination is perfected, and he is given oral brompistigmine tablets 60 mg tid.
Nisson 40mg qd
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 What puzzles Bai Jiao is that after a few days of treatment, the patient’s symptoms have not been alleviated at all.
Bropistigmine tablets are short-acting preparations, especially for patients with AchR(+).
Symptoms should improve temporarily after taking the medicine.
Is Musk antibody positive? At this time, the patient's RNS examination has also been completed, and the result is negative, which makes the diagnosis of MG even more confusing
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 “The patient’s right eyelid is drooping, the right eyeball is completely fixed, and it is positioned on the cranial nerves of III, IV, VI.
It can be the skull base supraorbital fissure syndrome and part of the cavernous sinus syndrome.
We took out the patient’s head MRI and reviewed it.
Come on
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" Zhou Feng suggested to Bai Jiao
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 "But his AchR-Ab(+) is very puzzling, and the head MRI report is also normal
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" Bai Jiao shook his head helplessly, while inserting the patient's film into the reading light
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 The two watched the film carefully again, focusing on checking the midbrain and pontine for lesions.
They still found nothing, but felt a little suspicious at the level of the right cavernous sinus
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(See the picture below) "Let’s do an enhanced examination.
Although the patient AchR-Ab(+), taking brompistine tablets is not effective, and the phenomenon of light and heavy in the morning and evening during the hospitalization period is not obvious
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" Zhou Feng Say
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 Bai Jiao felt that Zhou Feng's suggestion made sense, so he arranged an enhanced head MRI examination for the patient
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 As Zhou Feng expected, the patient had meningioma next to the cavernous sinus on the right side
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(See the picture below) So far, the truth is revealed.
Originally, AchR-Ab was an important item for diagnosing MG, with a specificity of 99%, but in this case it became an interference item.
It seems that it is clinically based, and it is easy to be mistaken for the test results.
Go astray
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 Later, Bai Jiao consulted a colleague in the laboratory.
The colleague told her that the results obtained by different detection methods are very different.
Radioimmunoassay is the gold standard, but the ELISA method is prone to false positives or false negatives
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 Adapted from the essay "Follow the clinic, please hold the patient's hand" by Mr.
Zhao Chongbo