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OBJECTIVEHemorrhage (also known as apoplexy) in optic pathway gliomas (OPGs) is rare. Because of the variable presentations and low incidence of OPG hemorrhages, little is known about their clinical course and the best treatment options. The aim of this work was to review risk factors, clinical course, and treatment strategies of optic glioma hemorrhages in the largest possible number of cases.METHODSA total of 34 patients were analyzed. Nine new cases were collected, and 25 were identified in the literature. Data regarding demographics, radiological and histological features, treatment, and outcome were retrospectively reviewed.RESULTSThe majority of patients were younger than 20 years. Only 3 patients were known to have neurofibromatosis. The histopathological diagnosis was pilocytic astrocytoma in the majority of cases. Five patients had intraorbital hemorrhages, whereas 29 patients had intracranial hemorrhage; the majority of intracranial bleeds were treated surgically. Six patients, all with intracranial hemorrhage, died due to recurrent bleeding, hydrocephalus, or surgical complications. No clear risk factors could be identified.CONCLUSIONSIntracerebral OPG hemorrhages have a fatal outcome in 20% of cases. Age, hormonal status, neurofibromatosis involvement, and histopathological diagnosis have been suggested as risk factors for hemorrhage, but this cannot be reliably established from the present series. The goals of surgery should be patient survival and prevention of further neurological and ophthalmological deterioration.

Optic pathway/hypothalamic gliomas represent approximately 2%–5% of brain tumors in children. Total excision, subtotal excision, subtotal excision followed by irradiation, radiation therapy alone, chemotherapy, and no treatment at all have been reported. In this article the authors discuss the results of Gamma Knife surgery (GKS) for optic gliomas in 2 children. Two pediatric patients, a boy and a girl, underwent GKS for optic gliomas at our hospital between March 2005 and August 2005. The children's ages were 10 and 16 years at presentation. The histological diagnosis was confirmed to be pilocytic astrocytoma in both cases. The tumor involved the optic chiasm in 1 patient and the right optic nerve in the other patient. Treatments were planned with the prescription of 11 Gy to the 50% isodose line for the optic chiasm glioma and 15 Gy to the 50% isodose line for the optic nerve glioma. In both patients, GKS was well tolerated. The follow-up periods were 60 and 55 months. Complete response with near-total disappearance of the tumors was observed in both patients. During the follow-up period, neither of the patients developed any endocrine dysfunction. Gamma Knife surgery permits treatment of optic glioma with good tumor control and no clinically relevant morbidity. With the ability to deliver a high dose to the tumor while sparing normal brain tissue, especially the optic nerve, optic chiasm, and pituitary gland, GKS should be the choice of treatment for optic gliomas. A larger number of patients and long-term follow-up are required for further evaluation of the efficacy and potential side effects of GKS.

✓ Tumors involving the optic nerve (optic glioma, optic nerve sheath meningioma) are benign but difficult to treat. Gamma knife surgery (GKS) may be a useful treatment. The authors present data obtained in three such cases and record the effects of GKS.

✓ A series of 104 patients with surgically verified optic nerve gliomas is presented. Anterior lesions primarily affecting the optic nerve were present in 42 patients, who have a long-term survival rate of 85.5%. Posterior lesions primarily affecting the optic chiasm were present in 62 patients, most of whom underwent radiation therapy postoperatively, and they have a long-term survival rate of 50%. Unequivocal signs of neurofibromatosis were present in 14%. On the basis of these findings and a review of the literature, recommendations are made for the surgical management of these tumors.

✓ Four patients with chiasmal syndromes were found to have intrachiasmal hematomas. Computerized tomography scans showed high-density suprasellar masses in all cases. Cryptic vascular anomalies were presumed to be responsible for spontaneous bleeding into the chiasm in three of the cases. In the remaining case, hemorrhage was due to an occult optic glioma. Surgical evacuation of clotted blood resulted in improved visual function in three of the four cases.

✓ A case is reported with occlusion and stenosis of the internal carotid arteries in association with basal telangiectasia. Fifteen years after postoperative irradiation for an optic glioma, radiological signs typical of the moyamoya syndrome were observed. Radiation therapy is discussed as the cause of the vascular damage in this case.

✓ Nine human optic gliomas were examined in tissue culture. Typically, growth from the explants revealed well differentiated bipolar cells with abundant 9 to 10 nm fibers similar to those observed in the surgical specimens. Multinucleation was rare except for one culture, which had as many as 20 nuclei arranged in a palisading fashion along the periphery of some of the cells. Degenerative changes of the 9 to 10 nm fiber bundles with the production of amorphous electron-dense deposits were observed both in vivo and in vitro, and were thought to represent the formation of Rosenthal fibers. A distinctive feature of some of the optic gliomas was the ability of their long, thin cellular processes to form fibrous tangles in tissue culture. The correlation of these fibrous tangles in culture with Rosenthal fibers in vivo is still uncertain.

✓ The authors report a case in which a suprasellar germinoma (ectopic pinealoma) was mistakenly interpreted as an optic glioma. The proper diagnostic and therapeutic procedures for the management of this lesion are discussed, emphasizing recognition of the characteristic triad of visual loss, hypopituitarism, and diabetes insipidus, as well as verification by biopsy and adequate radiation therapy.

✓ A retrospective series reviewing 28 cases of optic glioma in childhood is reported from the Columbus Children's Hospital. The literature is reviewed from a clinical and pathological standpoint; in the pathological literature there is support for consideration of these lesions as a neoplastic entity, but none for designation of these gliomas as “hamartomas.” An approach to the management of optic gliomas is presented. Treatment should be tailored to the individual patient; no clear therapeutic protocol appears to be supported by available data.

✓ Chiasmatic optic glioma is a rare tumor with an erratic natural history, usually seen in young children. A prior study from this institution demonstrated that these lesions were frequently lethal, despite initial clinical stabilization following radiation therapy, and that visual, intellectual, and late endocrinological disabilities were prevalent. A novel approach was developed in 1977, when an initial clinical response to vincristine was recorded in a child with a recurrent optic glioma. Since then, all children with recurrent optic glioma and all children aged 6 years old and under with newly diagnosed optic glioma have been offered a program of initial therapy with vincristine and actinomycin D for six cycles over 18 months. The four children with recurrent tumor who were treated with that regimen remain clinically stable 13 to 115 months after chemotherapy. Twelve children (eight under 24 months old) with newly diagnosed optic glioma have been treated with this program, and three are still on therapy. Four developed progression while on therapy, and five remain stable from 1 to 60 months posttherapy. The four children who developed progressive disease have been treated with radiation therapy and remain stable. Six of the 12 children showed shrinkage of their tumor on computerized tomography while receiving chemotherapy. This program may serve as an alternative to initial radiation therapy in young children.

✓ A case of bilateral enlargement of the optic canals by a craniopharyngioma is documented, and the differential diagnosis from optic glioma is discussed.

ARIOUS manifestations of the unpredictable natural history of optic gliomas have resulted in controversy as to the best form of treatment. Some reports of successful partial removal of these tumors 1,12 may be questioned because of the limited follow-up period at the time of reporting. Taveras, et al., 1~ described remissions and arrest with improvement in exophthalmos and vision in a group of patients treated by radiotherapy alone. On the basis of this experience they concluded that tumors limited to the orbital cavity may be treated successfully by intraorbital surgical removal but that all other cases should be treated by irradiation. Later, Chutorian and his coworkers 2 at the same institution found four cases of recurrent optic nerve glioma following radiotherapy. One of these had been reported by Taveras, et al., ~ as free of recurrence after 21 years. Some ophthalmological surgeons have advocated transorbital excision of optic nerve gliomas as adequate therapy2 TM In one of the 13 cases in this report, the tumor recurred with chiasmal spread 6 years after orbital resection. These experiences lend credence to the impression that, although radiotherapy may be effective in nonresectable optic glioma, transcranial chiasmal inspection and prechiasmal resection is the treatment of choice when tumor is confined to a single optic nerve. Furthermore, excellent cosmetic results have been possible when the structures of the orbital apex have been meticulously approached by the frontal transcranial route. The operative technique to be described is based on our surgical experience with nine cases of optic glioma. Proptosis and visual impairment were the most common presenting symptoms. The diagnosis of optic nerve glioma may be made on the basis of radiographic evidence of enlargement of one optic foramen2 Pneumoencephalography has been useful in outlining the intracranial portion of the optic nerve. Preservation of the chiasmarie notch, between the optic and infundibular recesses of the anterior third ventricle, usually indicates that the chiasm is not involved. Radioactive mercury scan has been of great value as supporting evidence for the presence of optic nerve or chiasmal glioma. Technetium scanning has proved to be less reliable.

✓ The anatomy, radiological appearance, and diagnostic importance of the optic strut are described and five cases presented to illustrate its value in the diagnosis of infraclinoid aneurysms, optic gliomas, and orbital deformities associated with neurofibromatosis. A distinction is made between erosion and deformity of the optic strut.

✓ Malignant optic glioma in adulthood is a rare tumor that causes early loss of vision and nearly always leads to death within a year. A case history is presented illustrating the clinical and neuroradiological characteristics of the malignant optic glioma in adults. A review of the literature is given.