orbital mucocele
Introduction
Introduction to eyelid mucus cyst Mucocele is one of the common intraorbital lesions. It is usually found in the sinus and invades the sputum. It is rare in the sinus. Each sinus can occur, of which the frontal sinus is the most common, followed by the ethmoid sinus, which occurs in the maxillary sinus, sphenoid sinus and sacral air bubbles are rare. basic knowledge The proportion of sickness: 0.01% Susceptible people: no special people Mode of infection: non-infectious Complications: chronic suppurative sinusitis
Cause
Causes of orbital mucinous cyst
Secondary mucinous cyst (20%):
The exact cause of sinus mucinous cysts is still controversial. It is generally believed that it may be congenital natural sinus sinus or multiple causes of sinus occlusion. The most common are chronic inflammation of the sinus, allergic edema and polyps, etc. Is a sieve, frontal sinus basal cell carcinoma, metastatic tumor, involving the fracture of the nasal frontal tube, previous sinus surgery can also produce sinus occlusion and secondary cystic dilatation of the sinus, mucus retention and progressive compression to make the cyst Filled with the sinus, which in turn erodes and passes through the wall and displaces the soft tissue inside the sac, which is called a secondary mucinous cyst.
Primary mucinous cyst (20%):
Another theory suggests that small cysts occur in the lining of the sinus, perhaps from swollen goblet-cells. When the cysts enlarge, eventually the sinuses close, the cysts compress and erode adjacent bones. Primary mucinous cyst.
The sinus secretion protein content is too high (20%):
Since the 1970s, mucinous cysts have been thought to be caused by a series of biochemical and immune responses caused by excessive protein content in the sinus secretions, that is, the osmotic pressure in the sinus is increased, and the absorbed water is filled in the sinus cavity, causing the pressure in the sinus to increase. Osteoclasts in the bone wall are activated by prostaglandins, thyroxine, vitamin D, etc., and the osteoclast-activating factor produced by lymphocytes also participates, causing the sinus wall to be destroyed.
Prevention
Eyelid mucus cyst prevention
With the removal and treatment of the frontal sinus and ethmoid cysts, the ocular protrusion and displacement can be gradually disappeared after surgery. The general visual acuity is good. Late vision loss and ophthalmoplegia are more difficult to recover, and long-term sphenoid sinus cysts can undergo irreversible optic atrophy. Usually the systemic prognosis is good. However, after the sphenoid sinus mucinous cyst, serious consequences may occur due to the adjacent internal carotid artery and other important structural damage near the tip of the sac.
Complication
Eyelid mucus cyst complications Complications chronic suppurative sinusitis
The manifestations of primary nasal diseases include nasal congestion, chronic inflammation of the sinuses, and the like.
Symptom
Eyelid mucus cyst symptoms Common symptoms Eyebrow cyst cyst vision vision change cyst mucus cyst eyeball can not move freely on the sag eyelid muscle palsy double eyeball retraction eyeball protrusion
The fluid cyst develops slowly. When it is confined to the sinus, it lacks symptoms or signs, or only mild headache, cyst enlargement, local swelling or pain, sinus wall expansion, pressure like eggshell or table tennis-like feeling, clucking When the sound is heard, the cyst can rupture into the nasal cavity, intermittently overflowing with a lot of mucus, and the symptoms and signs are temporarily relieved. If an acute infection occurs, it is painful, red, swollen, tender, even aversion to cold, fever, and polymorphonuclear leukocytosis.
Most patients pay attention after cysts invade the eyelids. The appearance of the eye varies depending on the primary site of the cyst. It occurs in the frontal sinus or ethmoid sinus. The cyst is pressed, the eyeball is outward, the lower side is displaced, the eyeball is prominent, the medial side of the iliac crest is Internal upper quadrant and soft mass, the eyeball is restricted to the medial side, the cyst oppresses the eyeball, causing refractive error and vision loss. Due to the compression and inflammation of the cyst, it can cause subperiosteal hematoma of the eyelid, aggravating eyeball protrusion and displacement. , the forehead huge mucous cyst, can make the cranial cavity, sinus, eyelid communication, brain pulsation transmitted to the eyeball, causing pulsatile eyeball protrusion, in addition, frontal sinus cyst can cause the third brain cranial palsy, primary in the posterior ethmoid sinus and butterfly In the early stage, there is vision loss, often misdiagnosed as posterior optic neuritis. After the cyst invades the sacral cavity, the eyeball is prominent. Because the cyst is in the posterior part of the eyeball, it is characterized by axial eyeball protrusion.
Subject to pressure, primary optic nerve head atrophy, eye movement disorder, primary cysts of the sphenoid sinus in addition to the above symptoms and signs, such as upward development, involving the meninges, often cause headache; lateral development, compression of the cavernous sinus, supra Splitting, ptosis, eye muscle paralysis, diplopia; oppression of the optic nerve, causing vision loss and visual field loss in both eyes, maxillary sinus mucinous cysts clinical manifestations of various, can cause eyeball protrusion or eyeball retraction, diplopia, chin deformation, The lower nerve distribution area is abnormal, with tears and vision loss.
Examine
Eyelid mucus cyst examination
Pathological examination: cysts are sinus mucosa, often thinned by pressure, causing cells to lose cilia, but also due to chronic inflammation and fibrosis, normal pseudo-stratified ciliated columnar epithelial visible chronic inflammatory infiltration, sometimes polypoid The gland is cystic enlargement, and the contents of the cyst are mostly pale yellow, brown or dark green viscous liquid, sometimes bloody, containing cholesterol, the longer the course, the higher the concentration, from serous, mucinous, Cheese-to-gum-like, secondary infection, the liquid is filled with pus cells, the cyst develops slowly, gradually increases, the sinus bone is compressed and thinned, the sinus wall is smooth, and the larger sphenoid sinus cyst can compress and destroy adjacent bone Quality such as optic nerve hole, sacral tip, supracondylar sulcus, saddle back and ethmoid sinus, advanced frontal sinus mucus cyst can destroy the posterior wall of frontal sinus, making mucosa and dura mater to form a dural mucous cyst.
1. X-ray X-ray examination often found that the affected side of the sinus shadow opacity, sinus cavity expansion.
2. Ultrasonic cystic mass has a typical manifestation on ultrasound. B-mode is characterized by a special position above or inside the orbit of the lesion, and the shape of the lesion is circular or elliptical or irregular shaped lesion, and the internal echo is weak. The posterior cyst may be smooth or irregular. When the eye is scanned, a large cystic mass may be found in the upper or inner side of the iliac crest. Any cystic lesion in the upper or inner side of the eyelid should be considered as the possibility of mucous cyst first. It shows a typical cystic mass image, large volume, low internal reflection, and no obvious attenuation. The lesion is located in the upper or the lower side of the eyelid. The eyeball is often compressed, the boundary of the lesion is clear, and the peak of the cyst is high. It is easy to be misdiagnosed at this time. For lesions in the orbit, if the diameter of the lesion is found to be significantly larger than the distance between the eyeball and the wall of the eyelid, the spread of the sinus tumor should be considered first, and the possibility of the lesion in the eyelid spreading to the sinus is not excluded.
Ultrasound shows that the echo or reflection in the cyst is slightly different depending on the content of the lesion. For example, mucus with uniform density, ultrasound shows no echo or liquid level; if there is a cluster of pus or mucus mixed with other forms Points, the ultrasound shows a weak echo.
3. CT scan visible lesions originated from the frontal sinus, ethmoid sinus or frontal ethmoid sinus, sinus cavity enlargement, increased density, homogenization, coronary CT can show the relationship between lesions and eyelids, sinus wall often disappears due to chronic compression, cyst invasion In the iliac crest, the internal structure of the iliac crest is displaced. If the periosteum of the ruptured eyelid enters the orbit, the eyelid abscess or cellulitis symptoms and imaging findings appear.
For example, cysts occur in the frontal sinus, and the lesions invade above the iliac crest. When the transverse axis is CT, it is easy to diagnose the primary tumor in the sac, because the horizontal axis CT can not show the relationship between the lesion and the sinus.
Larger mucous cysts can compress the walls of the tibia and become thinner, absorbed or even missing. The lesions spread to the adjacent bones and intracranial, causing headaches and other symptoms.
4. Different stages of MRI lesions may have different signal intensity. The lesions begin to have a large amount of water in the mucus, T1WI is a medium-low signal, T2WI is a high signal, protein concentration increases in the chronic phase, water is gradually absorbed, and cysts are on T1WI and T2WI. For high-signal, longer-lasting lesions, T1WI and T2WI, are low-signal. If it is a mucinous abscess, the viscosity of the infected component increases, and T1 is shortened. The cyst itself has no enhancement, while the cyst wall has signal enhancement.
Diagnosis
Diagnosis and differentiation of orbital mucinous cyst
In addition to the typical clinical manifestations, the diagnosis of mucinous cysts relies mainly on imaging examination and puncture to extract mucus, and the diagnosis can be confirmed by the combination of imaging, especially CT scan.
Mainly differentiated from sinus malignant tumors, the latter lesions were solid and progressed rapidly. Ultrasound showed solid non-uniform echoes, and the attenuation was obvious. CT and MRI showed obvious bone destruction.
