Ocular muscle weakness should refer specifically to extraocular muscle weakness, as the eye itself does not have a muscle. There are many diseases that can cause symptoms of extraocular muscle weakness, such as intracranial tumors, occupying lesions, inflammatory conditions, and even cranial nerve injury caused by blood clots and immune factors. Certain diseases, such as endocrine disorders, thyroid-related eye disease, ophthalmologic disorders, and even mechanical compression and trauma, can also lead to symptoms of extraocular muscle weakness and should be clinically differentiated. The ocular muscles refer to the extraocular muscles, which include many kinds of muscles, as follows: 1. The most common is the levator aponeurosis: the levator aponeurosis is at the periphery of the eyelid and governs the eye opening action, so weakness of the extraocular muscles can lead to symptoms of ptosis, which is innervated by the motoneurotic nerve; 2. The orbicularis oculi: the orbicularis oculi is around the eye and governs the eye closing state, which is innervated by the facial nerve; 3. Inside the eye, the eye is surrounded by six small muscles: namely, the internal rectus, external rectus, superior rectus, inferior rectus, superior oblique, and inferior oblique muscles, which are innervated by the motoneurotic, talonavicular, and adductor nerves of the cranial nerve.