Tumors of Optic Pathways.

Hane, Y S; Han, Y P; Park, T S; Lee, H J

Original Article

Journal of Korean Neurosurgical Society 1973;2(1): 89-96.

Department of Neurosurgery, Yonsei University College of Medicine, Korea.

ABSTRACT

Gliomas of the optic pathway make up a relatively small portion of all neoplasm of the brain with an incidence of 0.84~3.6%. Since this tumor arises in the tract of optic pathways, one might expect to find any of the types of neoplasm arising in the glial tissue. Consequently the absence of mitoses is evidence that these tumors do not enlarge by cell invasion. A collateral hyperplasia of adjacent glia and connective tissue is an ample evidence of the benignancy, although the most gliomata of the optic nerve are indolent. Two cases of this communication comprised a tumor growth into the 3rd ventricle obstruction both foramina of Monro with subsequent clinical features of hydrocephalus. There is difficulty in obtaining X-ray films showing the optic canal in its entirety. The presence of full sized optic foramina in young children is also significant. The combination of J-shaped sella deformity with enlargement of the optic canal was associated with the massive intracranial extension of the tumors with obstructive hydrocephalus. Conary ventriculography was a valuable diagnostic adjunct outlining the extent of the tumor growth. Exploratory craniotomy should not be negated by the reason that modern neurosurgical procedures can permit an accurate diagnosis and assessment of the extent of the tumors. Incomplete excision is no sin as Hudson (1912) established so convincingly. We continue to believe that histological confirmation of the presence of the tumor represents a proper and justifiable practice. Our experience suggests that effort to relieve the increased intracranial pressure by shunt procedure rather than radical excision of the tumor mass are indicated.