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Clinical course of the case of a now 20 patient, with glioma of the optic nerve, removed 12 years ago, is presented. The tumour was removed with a intraorbital part of the optic nerve, but the eyeball was saved, what enabled the normal, symmetrical development of the child's face. Painful atrophy of the eyeball occurred 10 years after surgery and it seems that there will be a necessity to remove the eye.  相似文献   

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Medulloepithelioma of the optic nerve is a rare developmental tumor. We describe a 2-year-old boy with profound loss of vision associated with a visible tumor of the optic nerve head in his left eye. A clinically diagnosed retinoblastoma necessitated left eye enucleation. The histopathological diagnosis was malignant medulloepithelioma that was incompletely resected. Further tumor resection was required, and the patient received adjunctive chemotherapy and radiotherapy. Four years after treatment, the patient has neither clinical nor radiological evidence of tumor.  相似文献   

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Optic nerve sheath decompression (ONSD) has become a more frequently performed surgical procedure in recent years. We describe the surgical techniques and complications and we detail the indications of ONSD in pseudotumor cerebri, ischemic optic neuropathy due to arteriosclerosis and other etiologies under investigation. With a 2% risk of postoperative blindness, this procedure must be indicated only in case of severe visual loss and performed by surgeon experienced to orbital surgery.  相似文献   

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A boy with a large intracranial glioma of the optic tract and probable neurofibromatosis of the first type was observed for 8 years since the age of 7 years. A series of MR scans was made over this period. A notable decrease of the tumor size was seen on its signals on the MR scans. This was paralleled by an improvement of the vision acuity, color field, and visual field on the involved eye. Patient's grandmother had an intracranial glioma of the optic nerve with a slight but stable decrease of the visual functions. The tumor shape in the grandmother and grandchild is remarkably similar. This finding in the grandmother and stability of her vision decreased from childhood permit us to propose that the tumor did not develop and even regressed with time.  相似文献   

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A case of bilateral optic nerve meningioma is reported. The onset of the clinical symptoms, at age 27, resembled unilateral optic neuritis with papilledema, leading to bilateral amaurosis with optic atrophy 4 years later. Skull X-ray revealed a "blistering' type of bone reaction. In the carotid angiogram, the ophthalmic artery appeared quite enlarged and displaced. The CT scan showed a fusiform enlargement of both optic nerves. Pathological diagnosis was based upon an optic nerve biopsy. Including the present case, only 12 instances of bilateral optic nerve meningioma have been reported.  相似文献   

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To identify genes necessary for establishing connections in the Drosophila sensory nervous system, we designed a screen for mutations affecting development of the larval visual system. The larval visual system has a simple and stereotypic morphology, can be recognized histologically by a variety of techniques, and is unnecessary for viability. Therefore, it provides an opportunity to identify genes involved in all stages of development of a simple, specific neuronal connection. By direct observation of the larval visual system in mutant embryos, we identified 24 mutations affecting its development; 13 of these are larval visual system-specific. These 13 mutations can be grouped phenotypically into five classes based on their effects on location, path or morphology of the larval visual system nerves and organs. These mutants and phenotypic classifications provide a context for further analysis of neuronal development, pathfinding and target recognition.  相似文献   

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Blood flow to the retina and optic nerve remains constant over a range of elevated intraocular pressure or mean arterial pressure, independent of sympathetic activation (pressure autoregulation). In addition, increased metabolic activity in these tissues proportionally increases blood flow (metabolic autoregulation). At constant metabolic rate, altered arterial oxygen content reciprocally alters blood flow, leaving total oxygen delivery constant, while blood flow rises and falls with the arterial carbon dioxide tension. These responses are similar to those of the cerebral circulation. However, while aging, atherosclerosis, arterial hypotension, and individual variation may profoundly alter blood flow regulation and predispose to the development of illness, these factors remain largely unexplored.  相似文献   

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Bone-resorbing multinucleated cells were efficiently formed in primary culture of cells isolated from synovial tissues of patients with rheumatoid arthritis in 2-3 weeks in the presence of 1,25(OH)2vitaminD3 without any additional stromal cells, and that formation was further facilitated by macrophage-colony stimulating factor. Furthermore, we show that osteoclast-like cells are formed in co-culture of peripheral blood mononuclear cells and rheumatoid synovial fibroblasts obtained by continued sub-cultures. The multinucleated cells showed all the phenotypical and functional characteristics of osteoclasts including the expression of tartrate resistant acid phosphatase, vitronectin receptors, receptors for human calcitonin and the ability to resorb bone. These results indicate that synovial macrophages are capable of differentiating into osteoclasts in the presence of rheumatoid synovial fibroblasts which can support differentiation of monocytes/ macrophages, implicating that osteoclasts generated within the synovial membrane are probably involved in bone destruction in rheumatoid arthritis.  相似文献   

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In this study the extracellular distribution of cytochemically generated calcium reaction product in the denervated optic tectum of a cichild fish (Oreochromis mossambicus) was investigated. The left optic nerve had been transected and the fish (5 per experimental condition) maintained for 2, 10 and 21 days. The amount of the calcium-containing precipitates was estimated using energy-filtering transmission electron microscopy (EFTEM) and image analysis. A special degeneration type of the optic terminals (neurofibrillar hypertrophy) was found which seems to be rare in other teleosts and was therefore chosen for quantification of the calcium deposits. These terminals are surrounded by astroglial processes and the calcium reaction product in the extracellular spaces between these glial processes and the terminals was measured and compared to normal optic terminals in nonoperated controls. A distinct and significant increase in the amount of calcium deposits was found 2 and 10 days after surgery which decreased to control levels after 21 days. This rise of deposits around the degenerating terminals was very local as arbitrarily selected extracellular spaces near these terminals showed values which were at the level of the nonoperated controls. Therefore, a transient and local increase in extracellular calcium precipitates was found after optic nerve transection which affected only the degenerating synapses.  相似文献   

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To test the possible involvement of platelet-derived growth factor B-chain (PDGF-B) in anterograde and retrograde degenerations of the CNS neurons, we studied the changes of PDGF-B localization and its mRNA expression in the rat retina and optic nerve (ON) after unilateral ON transection, using immunohistochemistry and in situ hybridization. In the control retinas immunoreactivity for PDGF-B and its mRNA expression were localized in the retinal ganglion cells (RGCs) and the nerve fiber layer. After ON transection PDGF-B immunoreactivity in the nerve fiber layer started to decrease on post-injury day 3 or 4. Atrophic changes in the RGCs started on day 5 just after the decrease of PDGF expression, and thereafter the RGC number decreased. In the longitudinal section of the ON rostral to the transected site, swollen axons showed intense PDGF-B immunoreactivity and macrophages, and some glial cells revealed a significant increase in both immunoreactivity and hybridization signals. Based on these findings, we hypothesized that the decrease in PDGF-B in RGCs after axotomy causes the loss of RGCs, and that increased PDGF-B expression in the ON plays a role in the cascade of tissue reactions following ON transection.  相似文献   

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Complex methods of statistic analysis for parameters of automated perimetry and visual evoked potentials were presented. The examinations were performed in 14 patients with compressive visual neuropathy, in 14 patients with optic neuritis, in 20 patients with demyelinative visual neuropathy and in 20 patients with optic nerve atrophy. Multidimensional analysis of variance (MANOVA) was performed. The methods proved useful for differential diagnosis of optic neuropathy.  相似文献   

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Adrenoleukodystrophy is an X-chromosome-linked recessive disease characterized by primary atrophy of the adrenal glands with or without Addison's disease and low plasma cortisol levels, and a degeneration of white matter of the central nervous system with blindness. In suspected cases of adrenoleukodystrophy an impaired rise in plasma cortisol levels after adrenocorticotrophin stimulation may be diagnostic. With the electron microscope, pathognomonic intracytoplasmic lamellar inclusions have been seen in adrenal cortical cells, peripheral nerve Schwann's cells, testicular interstitial cells, and in macrophages of the brain. Adrenoleukodystrophy appears to be a genetically determined lipid storage disease with an error in membrane sterol metabolism. A 10-year-old boy with adrenoleukodystrophy had visual loss, a prominent early symptom. The ocular abnormality consisted of a disproportionate loss of nerve fibers from the macular region. No intracytoplasmic lamellar inclusions were identified in cells representing macrophages within the optic nerve. They contained myelin debris suggestive of end-stage disease.  相似文献   

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Recent research has related pedalling frequency to perceived exertion, indicating that subjects pedalling at higher frequencies tend to perceive lower levels of exertion. If tests administered at higher pedalling speeds are valid, then more accurate data on extremely low fit individuals might be possible. The purpose of this study was to determine the validity of the Wahlund-Sjostrand W170 test administered at 50 and 80 rpm. Maximal oxygen intake was determined for thirty male volunteer college students using standard open-circuit techniques. W170 tests were administered at 50 and 80 rpm using standard test protocol. The results indicated a differential effect of pedalling speed upon the validity of the W170 tests. Validity coefficients of rxy = 0.73 and rxy = 0.64 were found for the 50 and 80 rpm tests, respectively. Maximal oxygen intake predicted from the W170 test administered at 80 rpm was significantly different from both the criterion maximal oxygen intake and the W170 prediction at 50 rpm. This difference was attributed to a significantly higher heart rate response to 80 rpm tests at the lower workload of 600 kpm/min. It was concluded that more valid W170 tests are attained at the conventional pedalling speed of 50 rpm.  相似文献   

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