| OCR Text |
Show 54 LITERATURE ABSTRACTS quently from vertebral-basilar ischemia. This would certainly be consistent with the pathology in the present case report. Walter M. Jay, M.D. Moyamoya Pattern of Vascular Occlusion after Radiotherapy for Glioma of the Optic Chiasm. Beyer RA, Paden P, Sobel OF, Flynn FG. Neurology 1986;36:1173-8 (Sept). [Reprint requests to Technical Publications Editor, Letterman Army Medical Center, Presidio of San Francisco, CA 94129-6700.] In the moyamoya pattern of vascular occlusion, there is an extensive basal cerebral rete mirabilea network of small anastomatic vessels at the base of the brain associated with occlusion of the terminal parts of both internal carotids. This vascular pattern was seen on arteriography in three children following intracranial irradiation for optic chiasm gliomas. All three patients had suffered massive strokes. Two of the three exhibited dramatic reduction in tumor size on computed tomography. There is controversy as to what is the appropriate therapy for chiasmal gliomas. Although radiation is commonly used in the treatment of chiasmal gliomas, its value is questioned by many. This article reviews three cases with severe complications of radiation therapy. Another recent article discusses two cases with similar complications. (Okuno T, Prensky A, Gado M. The moyamoya syndrome associated with irradiation of an optic glioma in children: report of two cases and a review of the literature. Pediatr Neurol 1985;1: 311-6.) In the present study, each of the three patients received more than 5,000 rads. Most authors recommend using fewer than 5,000 rads, especially in children under two. Proponents of radiation therapy could argue that the complications were not due to radiation therapy but to an excessive dosage. However, the two cases reported by Okuno et al. received fewer than 5,000 rads. Walter M. Jay, M.D. Near~EvokedNystagmus in Spasmus Nutans. Chrousos GA, Matsuo V, Ballen AE, Cogan DG. J Pediatr Ophthalmol Strabismus 1986; 23:141-3 (May/ June). [Reprint requests to Georgia A. Chrousos, M.D., Department of Ophthalmology, Georgetown University Medical Center, 3800 Reservoir Road N.W., Washington, D.C. 20007.] Spasmus nutans is characterized by nystagmus, head nodding, and an abnormal head position. The nystagmus is usually horizontal, of small amplitude, and of high frequency. It is often unilateral. When both eyes are involved, it tends to be asymmetric. The present article describes two cases of atypical spasmus nutans with nystagmus present only at near fixation. In the first case, nystagmus at near fixation could be blocked by covering either eye. In the second, covering either eye at near fixation alone did not dampen the nystagmus. However, the combination of occluding one eye and placing a + 3.00 spherical lens in front of the viewing eye eliminated the nystagmus. The authors concluded that in the first case, fusional convergence was necessary for development of nystagmus and in the second, accommodative convergence was. A clinical picture similar to spasmus nutans has been described in children with brain tumors, particularly of the anterior visual pathways. Some authors argue that all patients with spasmus nutans should be studied with computed tomography. It is not stated whether computed tomographic scanning was carried out on the authors' two patients. At any rate, both were followed over time. In the first, nystagmus disappeared, and in the second, episodes of nystagmus became less frequent. Walter M. Jay, M.D. A Severe Carotid-Cavernous Fistula Treated with a Balloon Catheter. Harbour RC, Luxenberg MN. Arch Ophthalmol 1986;104:1084-5 (July). [No reprint information given.] This "photo essay" depicts a 35-year-old man who had had a gunshot wound to the left side of his face 8 years previously. He had all the usual ophthalmic signs of a carotid-cavernous fistula and also quite remarkable, dilated, tortuous forehead veins. He was successfully treated with balloon occlusion. Lyn A. Sedwick, M.D. |
