congenital microphthalmia with orbital cyst
Introduction
Introduction to congenital small eyeballs with orbital cysts Congenital eyeball malformations and variability, mostly combined with craniofacial and orbital dysplasia. Most of them combined with severe congenital craniofacial abnormalities. basic knowledge The proportion of illness: the incidence rate is about 0.001% Susceptible people: children Mode of infection: non-infectious Complications: Cleft lip Eyelid meninges - brain swelling
Cause
Congenital small eyeball combined with the cause of orbital cyst
(1) Causes of the disease
During the embryonic period, the occurrence and development of the eyeball passes through the eyeball, the eye cup and the embryonic fissure are closed for several periods. When the embryo develops to 3.2 mm long (3 weeks), the forebrain bulges on both sides to form an eye blister, which is 4.5 mm long to the embryo. The distal end and the lower direction are recessed to form an eye cup. The name of the cleft under the eye cup is fissure, and the mesodermal tissue passes through the fissure into the embryonic eye. When the embryo develops to 12 mm (5 weeks), the embryonic fissure begins to close, and the embryo is 17 mm. Closed completely, the mesoderm tissue around the eye cup forms choroid and sclera, etc. If the embryonic fissure fails to close on time, the eye cup component grows out of the eye through the corresponding gap of the middle embryo leaf, and the eyelid cyst is formed. The cyst is immature. The retina is missing from the ocular wall by a spherical mass that is outwardly ejected, and is integrated with the small eyeball.
(two) pathogenesis
Congenital small eyeball malformation is the result of the development of the fetus during the development of the fetus, and the development of the eyeball after the embryonic fissure is closed. If it is not accompanied by an eye or other congenital malformation, it is often referred to as a true small eyeball or a single gnome small eyeball (nanophthalmos), or It is called pure microphthalmic. The small eyeball combined with the orbital cyst is caused by the incomplete closure of the embryo during embryonic development. In the unclosed gap of the small eyeball, the nerve epithelium proliferates, forming an orbital cyst through the gap, which is filled with liquid. Most of them are located under the small eyeball, and are closely connected with them, mostly unilateral onset.
Prevention
Congenital small eyeball with prevention of orbital cyst
Pay attention to prenatal examination and diagnosis to improve the eugenic rate.
Complication
Congenital small eyeball complicated with orbital cyst complications Complications, cleft lip, meninges, brain swelling
In addition to eye abnormalities in the clinic, a few cases are accompanied by congenital malformations in other parts of the body, such as cleft lip, wolf pharynx, small head, lack of optic tract and lateral geniculate body, less white matter in the brain, and meninges-brain bulging. Cardiovascular and genital dysplasia and other abnormalities.
Symptom
Congenital small eyeball with eyelid cyst symptoms Common symptoms Small eyeball cyst conjunctival foreign body eyeball floating phenomenon
Small eyeballs and cysts occur in the embryonic period, and are found by parents after birth or in infancy, mostly in one eye, about 1/3 in both eyes, initial eye socket collapse, small cleft palate, small eyeballs in the conjunctival sac, or The eyeball is too small, covered by the conjunctiva, the eyeball can not be found, the conjunctiva can be opened with the eye hook, and the black gray cornea and the eyeball can be found at the top of the conical conjunctival sac. As the age increases, the cyst gradually enlarges and the chin bulges forward. Blue, can be soft and swollen, small eyeballs are displaced upwards, the lower conjunctiva is also blue-blue bulge, or protrudes from the cleft palate, there is a clear liquid in the mass, and the surface of the lower jaw and conjunctiva shines, the whole cyst is translucent In general, the cyst is located below the eyeball. After the squat, about 6% of the cyst is located above the eyeball. This is because the cyst is from the bottom to the eyeball, or the atypical embryonic fissure is above. Occasionally, the small eyeball and the cyst are not obvious. Contact, only histopathological examination can confirm the close relationship between the two.
Examine
Congenital small eyeball with eyelid cyst examination
Pathological examination: Congenital small eyeballs may be inconsistent due to different degrees of pathological development. The giant examinations are small in size, small in shape, connected to a large cyst underneath, and the lens is opaque and calcified in the small eyeball. It can be adhered to the posterior retina, the retina is not differentiated or poorly differentiated, and the chrysanthemum-like cells and gliosis are seen. The embryonic fissure under the eyeball is not closed. The immature retina is continuous with the inner wall of the intrasacral cyst. Or several, round, irregular or lobulated, pigmented membrane and vitreous can enter the cyst a short distance, the cyst wall is divided into two layers, the inner layer is a retinal layer of varying degrees of differentiation, often not completely lining the capsule On the inner wall, proliferating glial cells and incompletely developed retinas are seen under the microscope. Occasionally, chrysanthemum-like primitive retinal cells are arranged. The outer layer of the cystic wall is fibrovascular tissue, which is caused by cystic compression of surrounding tissues and fibroblast proliferation. The capsule contains a pale yellow clear liquid with trabeculae and exfoliated cells, and the protein and chloride content is similar to cerebrospinal fluid.
1. X-ray without eyeballs or small eyeballs, showing that the orbital fossa is small and round, and there are spherical soft tissue shadows in the iliac crest. The ipsilateral humerus and optic nerve holes are generally less developed or even absent, congenital. Small eyeballs combined with intraorbital cysts, such as small cysts, eyelid development is small; if the cyst is larger, the orbital fossa can be normal or enlarged deformation.
2. Ultrasound (US) examination can clearly show whether there are eyeballs and small eyeballs, such as cysts, mostly without echo, and connected with the eyeball, deformed with compression.
3. CT manifests as lack of eyeball or narrow eye ring. Three-dimensional imaging can show that sputum development is small, or combined with other craniofacial bone abnormalities, such as persistent primary vitreous hyperplasia or slight increase in vitreous density, flat sputum Small eyeballs have high or low density shadows. The cysts in the eyelids appear as low-density areas, often located in the lower back of the eyeball. The boundary is clear, and the contents of the posterior capsule are not strengthened. The larger one can oppress the adjacent structure, the eyeball is prominent, and the eye socket can be enlarged. The optic nerve is thin or absent, but the extraocular muscles and lacrimal glands are present.
Diagnosis
Diagnosis and differentiation of congenital small eyeball with orbital cyst
Small eyeballs are found after birth. As the child grows, the lower jaw gradually rises, reveals a blue-blue color, and can be combined with a soft mass. These typical clinical findings can make a correct diagnosis. Ultrasound exploration reveals small eyeballs and The cysts connected to it, lack of echo in the capsule, CT scan can be seen with the small eyeball attached to the eyelid and the high-density space-occupying disease in the lower part of the eyelid. The CT value is quite different. After the contrast agent is injected, the ring is strengthened, and CT can also find . The volume is obviously enlarged, sometimes the small eyeball forms calcium spots. MRI finds that the cystic mass is under the small eyeball, the boundary is clear, T1WI is low signal, and the intensity is slightly higher than that of the vitreous. On T2WI, the signal intensity is increased to high signal. The intensity is slightly lower than that of the vitreous, but higher than the fat signal intensity.
Because the disease is found in infants and young children, it needs to be differentiated from cystic eyes, capillary hemangioma and meningeal bulging. The cystic eye occurs on one side, there is a large cystic eye in the conjunctival sac, and large eyes and meninges are found by ultrasound and CT. The bulging is seen on the inside of the eyelid, with spontaneous pulsation, X-ray and CT findings of bone loss, capillary hemangioma occurring in the upper or lower jaw, purplish red, soft, solid mass, swollen when crying, color Doppler Ultrasound revealed a diffuse red-blue blood flow signal in the tumor, which is a specific ultrasound sign.
