Glioma of the optic nerve is a rare intracranial tumor that most commonly occurs in
children. It is slowly growing tumor most commonly exhibiting a fusiform shape. It
consists of mainly fibrillary or pilocytic astrocytes and partly of oligodendroglias.
At present, the orgin and nature of this tumor are not clear, although many authors
consider it as a congenital harmartoma rather than a true neoplasm.
Recently we experienced two cases of optic nerve glioma. The first case was a six
month old male infant who had right exophthalmos discovered fifteen days prior to
admission. Any abnormal physical findings were not noted except for suspicous lateral
gaze palsy. On operation, there was a fusiform mass, 1.5×1.0×1.0㎝, in the retrobulbar
region of the right optic nerve, which extended to the portion of left optic nerve, and
bilateral cranial portion of the optic nerves through the optic chiasm. Microscopically,
this tumor consisted of a mixture of spindle shapes and stellate astrocytes. In some
areas, microcystic changes were also noted. Occasionally Rosenthal fibers were observed.
The second case was a sixteen years old female patient who sufferer from loss of
visual acuity ten month before admission, and progressive exophalmos for four months.
On operation, there was a fusiform mass, 3.0×1.5×1.3cm, in the retrobulbarregion of the
left optic nerve. It has light yellow color and rubbery consistency, and extended near
the left optic foramen. On microscopic examination, this tumor was composed of fibrous
astrocytes and oligodendroglia. In relatively loose areas, there were moderate to severe
microcystic changes.
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