Optic radiation involvement in optic pathway gliomas in neurofibromatosis

Optic pathway gliomas (pilocytic astrocytomas) in neurofibromatosis type 1 (NF-1) typically involve some combination of the optic nerves, chiasm, or optic tracts. Involvement of the optic radiations is rare.

This paper describes seven patients with NF-1 with gliomas involving the pregeniculate optic pathway in addition to the optic radiations.

A retrospective database review was made of all patients with NF-1 and optic pathway gliomas seen by one of the authors (G.T.L.) at the Children's Hospital of Philadelphia from July 1993 to October 2001. Patients with involvement of pregeniculate optic pathway and the optic radiations were identified. From November 2001 to February 2003, patients were sought prospectively. Cases were also identified from the practice of another author (M.C.B.) at Arkansas Children's Hospital.

Four patients from Children's Hospital of Philadelphia (three of 83 total NF-1/optic pathway gliomas from July 1993 to October 2001 and one prospectively) and three from Arkansas Children's Hospital were identified. Two had expanding mass lesions within the white matter of the temporal or parietal lobes, which were histopathologically demonstrated to be pilocytic astrocytomas. The other five had radiographic involvement of the optic radiations but did not undergo biopsy. In three of the cases the vision was 20/200 or worse in each eye.

Optic pathway gliomas in NF-1 may rarely involve the optic radiations. Optic radiation involvement may signal a more aggressive optic pathway glioma in patients with neurofibromatosis-1.