Optic nerve tumors in children

Gliomas (astrocytomas) can affect the anterior visual pathway.

It is also possible for gliomas to develop in the orbit and cranial cavity.

Glioma of the optic nerve (orbital part)

In childhood, these neoplasms manifest themselves with a variety of symptoms:

• axial exophthalmos;
• decreased vision due to atrophy of the optic nerve;
• strabismus with or without limited mobility of the eyeball;
• optic nerve congestion;
• formation of optociliary shunts.

The characteristic signs of this pathology during radiographic examination are:

• tortuosity of the optic nerve directly in the retrobulbar region;
• dilation of the optic nerve canal.

Optic nerve gliomas are slow-growing pilocytic astrocytomas. Treatment tactics remain controversial to this day. In many cases, functions remain unchanged and the situation is stable over a long period.

Chiasmatic glioma

A more common neoplasm than orbital glioma, clinical manifestations typically include:

• bilateral visual impairment;
• nystagmus (possible facial spasm of nutans);
• strabismus;
• bilateral optic nerve atrophy;
• stagnant nipple;
• developmental delay;
• Exophthalmos is rare unless the optic nerve itself is involved in the pathological process.

Treatment tactics remain controversial, since many patients remain stable for a long time. Mandatory components of treatment are endocrinological examination and correction of identified endocrinological disorders, as well as, if necessary, treatment of hydrocephalus. In patients with progressive vision loss, the use of radiation and chemotherapy is justified.

Meningioma

It occurs very rarely in children, but can occur in adolescence.

Optic nerve meningioma

Manifests itself:

• loss of vision;
• mild exophthalmos;
• strabismus and double vision;
• optic nerve atrophy;
• the presence of optociliary shunts.

Vision loss may occur early in the disease and be complete if the tumor is located inside the optic nerve canal. Treatment is usually inappropriate, although surgical removal of the tumor and radiation therapy are sometimes performed. This pathology often accompanies NF2.

Extraorbital meningioma

In this pathology, the process involves the wing of the sphenoid bone, the area above the sella turcica, or the olfactory groove. Vision loss is associated with compression of the anterior visual pathway. Rarely occurs in childhood.

Rhabdomyosarcoma

Primary malignant neoplasms of the orbit in children occur extremely rarely, the most common of which is rhabdomyosarcoma. In most cases, the tumor develops at the age of 4-10 years, but there are data on the occurrence of this pathology in infants. Familial cases have been described, which are attributed to a mutation of the p53 gene, localized on the short arm of chromosome 17.

Clinical manifestations of the disease include:

• exophthalmos, which may appear suddenly, over several days, and tends to increase;
• erythema and swelling of the eyelid;
• ophthalmoplegia;
• ptosis;
• a neoplasm in the thickness of the eyelid that is accessible to palpation.

Rhabdomyosarcoma actively spreads due to invasive growth, in some cases there is involvement of the anterior or middle cranial fossa, pterygopalatine fossa or nasal cavity.

CT typically shows a homogeneous neoplasm with unclear borders. A biopsy is necessary to clarify the diagnosis.

The histological classification of rhabdomyosarcomas includes the following three groups:

1. anaplastic;
2. monomorphic;
3. mixed.

The life expectancy of these patients has increased due to early diagnosis of the disease and modern treatment methods. Management tactics include biopsy or partial removal of the tumor in combination with radiation and chemotherapy. Due to the possibility of serious complications associated with early irradiation of the orbit and eyeball, preference in the choice of the method of exposure is given to long-term chemotherapy.

Orbital dysplasia

Orbital fibrous dysplasia is a rare disorder of unknown etiology in which normal bone tissue is replaced by porous fibrous tissue. It usually manifests itself in childhood. Clinical symptoms depend on which wall of the orbit was initially involved in the pathological process.

1. Superior wall of the orbit:
   • exophthalmos;
   • downward displacement of the eyeball and orbit.
2. Upper jaw:
   • upward displacement of the eyeball;
   • persistent epiphora.
3. Sphenoid bone: atrophy of the optic nerve with involvement of the optic canal in the pathological process.
4. Sella turcica: compression of the chiasm with subsequent atrophy of the optic nerve.

Fibrous dysplasia is easily diagnosed by X-ray examination. It looks like thickened bone tissue with areas of sclerosis and cysts.

The treatment tactics consist of preventing vision loss due to optic nerve atrophy and resection of affected bone areas.