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At least 73 records · Page 4Linked to original sources

[Infantile optic glioma involving the whole optic pathway--a case report].

A case of infantile optic glioma involving the whole optic pathway is reported. The patient was a 4-month-old female. The mother noticed that the baby could not follow the object, although her physical development had been apparently normal only until three months after birth. On admission, she was lethargic, although no definite motor weakness was identified. The ophthalmological check revealed delayed bilateral pupillary light reaction and choked disks. Skull X-ray film showed the J-shaped sella and the enlarged bilateral optic canals. CT scan also revealed an isodensity mass in the suprasellar cistern and enlarged bilateral optic nerves. The lesions were enhanced homogeneously with contrast medium and extended toward both optic radiations. Lateral ventricles were mildly dilated. Cerebral angiography showed the upward shift of A1-portion of the bilateral anterior cerebral arteries and the backward shift of the basilar artery. No abnormal vessels were visible. A bifrontal craniotomy was performed to partially remove the suprasellar tumor. The histological diagnosis was optic glioma. The postoperative course was uneventful. The patient was discharged without any neurological deficits except poor visual acuity. Four months later, she suddenly fell into generalized convulsion. CT scan revealed the significant enlargement of residual tumor and ventricular dilatation. Surgical treatment of VP shunt was immediately performed on, and then irradiation of 4,000 rad of total dose to the tumor followed. The tumor size became definitively small. On a follow-up term of 15 months, the patient has been doing well.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral Angiography↗

Tuberculoma of the anterior optic pathways. Case report.

A tuberculoma, encasing the anterior optic pathways in a neoplastiform growth, was found in a 25-year-old man complaining of severe visual loss, diabetes insipidus, and sexual impotence following tuberculous meningitis. Following biopsy and anti-tuberculosis treatment, a satisfactory restoration of sight in one eye allowed the patient to resume an almost normal life.

Adolescent↗

Outcomes of systematic screening for optic pathway tumors in children with Neurofibromatosis Type 1.

Optic pathway tumors (OPT) occur in about 15% of individuals with Neurofibromatosis Type 1 (NF1) and may effect substantial visual loss. Because their growth is not predictable at the time of discovery, neuroimaging for OPT in asymptomatic NF1 patients remains controversial. We evaluated the outcomes of systematic screening by both MRI and ophthalmic examinations for OPT in young children with NF1 seen at multi-disciplinary clinics for Neurofibromatosis and Genetics at one institution between 1996 and 2001. We report on 84 children who presented with NF1 under age 6 years, of whom 13 children presented with either known OPT or abnormal MRI findings and 11 children had OPTs identified by neuroimaging, including two children with abnormal eye examinations at presentation (one with strabismus and one with optic atrophy). Nine OPTs were detected in asymptomatic subjects with normal ophthalmic examinations. Three children with chiasmal lesions enlarging on subsequent MRI were treated with carboplatin and vincristine. After treatment, the vision in each involved eye was intact. In contrast, the 13 children with OPT diagnosed outside of screening guidelines included five children with substantial visual loss. Our observations suggest that early recognition of NF1 promotes appropriate surveillance and allows early intervention to reduce complications of OPT. This analysis supports prospective studies to compare the outcomes of systematic screening with neuroimaging to screening with ophthalmic examinations alone in children with NF1.

Child↗

Optic pathway and hypothalamic/chiasmatic gliomas in children younger than age 5 years with a 6-year follow-up.

BACKGROUND: Gliomas of the hypothalamus and optic pathways (H/OPG) comprise 5% of pediatric intracranial tumors, present most frequently in patients younger than age 5 years, and may have a more aggressive course in younger children. This study examined clinical characteristics and consequences of treatment of young children diagnosed with H/OPG: METHODS: The authors reviewed the course, treatment, and outcomes of 46 children diagnosed with H/OPG younger than age 5 years; the median follow-up was 72 months. The median age at diagnosis was 27 months. RESULTS: Fifteen (33%) of 46 patients had neurofibromatosis-1 (NF-1). Forty children (87%) had tumor progression in the follow-up period, and tumor growth was less common in children with NF-1. Initial therapy was limited to surgical resection in three and radiation in five children. To postpone radiation until after the age of 5 years, initial therapy was limited to chemotherapy in 32 patients. Radiation was not required in 9 of these patients and was postponed for 40 months (mean) in 17. Of the 46 children, 5 died of tumor progression, 4 became blind, and 20 of 34 evaluable patients had endocrine abnormalities. Endocrinopathy did not correlate with therapy. Ten of 17 children evaluated by questionnaire required special education. There was a trend for educational problems to occur in children who were irradiated before the age of 5 years. CONCLUSIONS: Gliomas of the hypothalamus and optic pathways and their treatment cause long term morbidity in young children. Chemotherapy postpones radiation effectively, and this delay may reduce neurologic morbidity; however, 60% of children eventually relapse. By contrast, patients with NF-1 have indolent disease.

Child Behavior Disorders↗

Clinical implications of the fibre order in the optic pathway of primates.

Traditional neuro-ophthalmologic accounts of the optic pathway in primates stipulate that two half-retinal maps, one from each optic nerve, are combined within the chiasmatic region to yield a single, unified representation of the contralateral visual hemi-field in each optic tract. Yet visual disturbances produced by compromise to the visual pathways in the region of the describes recent neuroanatomical studies in monkeys that contradict those classical accounts but are consistent with the incongruous field defects and the functionally selective visual impairments documented in the clinical literature.

Animals↗

Incorporation of sialic acid into gangliosides and glycoproteins of the optic pathway following an intraocular injection of [N-3H]acetylmannosamine in the chicken.

Following an intraocular (i.o.) injection of [N-3H]acetylmannosamine, low molecular soluble radioactive label is distributed rapidly along the optic pathway. At the same time glycoproteins and gangliosides were found radioactively labelled in the distal parts of the optic pathway. Negligible amounts of radioactivity were incorporated into the same structures via the blood. The present data confirm, that glycoproteins are transferred in the retinal ganglion cells by a rapid axonal transport mechanism towards the nerve endings. Unlike glycoproteins labelled gangliosides accumulated in the optic nerves up to 4 days after the precursor injection. Simultaneously radioactive material, soluble in TCA/PTA, disappeared from the optic nerves. The specific radioactivities (disint./min/mug NeuNAc) of the single ganglioside fractions of the optic lobes, which contain the nerve endings of the retinal ganglion cells, differed considerably. Especially one fraction, moving on TLC plates identically to 'GD1a', was up to 20 times higher labelled than the other gangliosides. After an intracerebral injection of the same precursor, radioactivity was incorporated into the ganglioside fractions of the optic lobes to the same extent.

Animals↗

Optic pathway tumors in children: the effect of neurofibromatosis type 1 on clinical manifestations and natural history.

OBJECTIVE: To distinguish the clinical manifestations and natural history of optic pathway tumors (OPT) associated with neurofibromatosis type 1 (NF-1 OPT) from that of OPT not associated with NF-1 (non-NF-1 OPT). METHODS: Two groups of children with OPT were compared: (1) 17 children with NF-1 OPT who were followed prospectively, and (2) 19 children with non-NF-1 OPT who were identified retrospectively by a review of medical records. RESULTS: Precocious puberty was a common initial sign in the children with NF-1 OPT (5/17), and was not found in any patients without NF-1. In contrast, children with non-NF-1 OPT had symptoms attributable to increased intracranial pressure (12/19 and nystagmus (5/19); these symptoms were not found in any patient with NF-1. Decreased visual acuity at the time of diagnosis was common in both groups. There was no significant difference between the children with NF-1 OPT and those with non-NF-1 OPT as to age at diagnosis or sex distribution. Optic nerve involvement was more common in NF-1 (p < 0.001). Both isolated and bilateral optic nerve tumors were found exclusively in children with NF-1, whereas chiasmal (p = 0.016) and optic tract involvement (p = 0.001) were more common in those with non-NF-1 OPT. Radiographic evidence of hydrocephalus was found in none of the children with NF-1 OPT compared with 79% of the non-NF-1 OPT group. Progressive disease was seen in 12% of patients with NF-1 OPT compared with 63% of those with non-NF-1 OPT. CONCLUSIONS: Differences exist between NF-1 OPT and non-NF-1 OPT both at the time of diagnosis and during follow-up. Optic pathway tumors caused by NF-1 and non-NF-1 OPT have different biologic properties that distinguish both their initial clinical manifestations and their natural history.

Astrocytoma↗

[Optic pathway gliomas in neurofibromatosis type I. Longitudinal study of 30 cases in two multidisciplinary practices].

UNLABELLED: The aim of this study was to analyse the outcome of optic pathway gliomas in 30 children with neurofibromatosis type 1, the indications of treatment, and the follow-up and screening protocol. PATIENTS AND METHODS: All patients with a minimal two years follow-up (median six years, range two to 19 years), in two multidisciplinary consultations of Saint-Vincent-de-Paul (Paris) and Purpan (Toulouse) hospitals, were included in the study. In our series, we practiced systematic screening MRI in children under six years' of age or with neuropsychological deficiency that may imply an unreliable ophthalmological examination. RESULTS: Thirty-seven percent (11 patients) had progressive ophthalmological signs and were treated, and 63% (19 patients) were not progressive. Our study confirmed that most of optic pathway gliomas were stable during evolution, but rare cases may have bad prognosis. CONCLUSION: Our study supported the importance of close ophthalmological follow-up during childhood for which screening methods are discussed. There is a consensus to limit treatment for patients with progressive ophthalmological symptoms.

Adolescent↗

[The optic pathways: a magnetic resonance study at 1.5 tesla. I. Anatomy].

The authors retrospectively examined one hundred and twenty-nine patients who had undergone MR examination of the sellar, parasellar and orbital regions, to evaluate MR capabilities in demonstrating the optic pathways and their relationship to the most important anatomical structures nearby. T1-weighted images allowed a very good evaluation not only of the optic pathways as a whole, but also of the intracanalicular and intracranial segments of the optic nerve; the optic tracts and geniculate bodies were also clearly demonstrated. Optic radiations were clearly visible on both T1- and T2-weighted images. The orbital portion of the optic nerve could be evaluated with T1-weighted images, which showed its external profile. However, only multi-echo T2-weighted images allowed the nerve to be differentiated from perineural spaces, filled with cerebrospinal fluid, thus giving a true cisternographic effect.

Geniculate Bodies↗

Diffusion MRI in neurofibromatosis type 1: ADC evaluations of the optic pathways, and a comparison with normal individuals.

In a control group of 12 normal children (ages ranging from 9 months to 3 years; mean=1.6 years) the mean apparent diffusion coefficient (ADC) value of the normal white matter, obtained from automatically generated ADC maps, was 0.84 +/- 0.14 x 10(-3)mm(2)/s. A patient with neurofibromatosis type 1 with bilateral optic gliomas, and extensive optic pathway involvement was evaluated by diffusion MRI. Multiple measurements of ADC values throughout the involved optic radiations revealed a higher mean value: 1.16 +/- 0.06 x 10(-3)mm(2)/s than that of the normal white matter, suggesting relatively high molecular motion in these regions, probably representing myelin vacuolization. ADC evaluation of a thalamic hamartoma revealed a lower value (=1.06 x 10(-3)mm(2)/s) than this. The mean ADC value obtained from multiple measurements of the enlarged optic chiasm, and intraorbital portions of the nerve was similar (=0.81+/- 0.09 x 10(-3)mm(2)/s) to that of the normal cerebral white matter of the control cases. It appears that diffusion imaging can be useful in evaluation of optic pathway involvement in NF1, and might contribute to differentiating optic gliomas from hamartomas, and myelin vacuolization, however, further studies will be required for assessing the role of diffusion imaging in such lesions.

Case-Control Studies↗

Natural history and clinical management of optic pathway glioma.

Twenty-five consecutive unselected patients with optic pathway glioma (OPG) were primarily observed and treated if progression was evident. Diagnosis was based on MRI. The natural history of the OPG disease was more indolent in 12 patients with neurofibromatosis 1 (NF1) than in the others, and regressions were commonly observed. Thirteen non-NF1 patients had larger rumours at diagnosis and more progressions. There were five intra-orbital optic nerve tumours (one with progression), 19 chiasmatic tumours (12 with progression) and one diffuse tumour. OPG emerges before the age of 7 years in NF1 patients, and in non-NF1 patients also in older patients including adults. Progressive intra-orbital OPGs are best treated by surgical resection. Progressive chiasmatic tumours are best treated by radiotherapy and respond well by marked regression. Exceptionally, exophytic chiasmatic tumours may be treated by chiasm preserving surgery.

Adolescent↗

Carboplatin therapy for optic pathway tumors in children with neurofibromatosis type-1.

Symptomatic optic pathway tumors (OPT) occur in 7% of children with neurofibromatosis type-1 (NF-1). Although tumor progression following diagnosis is unusual in such children, specific therapy may be necessary for patients with either severe or progressive disease. We reviewed the records of 9 children (6 girls, 3 boys) with NF-1 associated OPT who were treated with the second generation platinum compound carboplatin. Carboplatin was given at a dose of 560 mg/mm2 every 4 weeks for a mean of 15 cycles. The mean age at presentation of the OPT was 3.4 years. Eight children had abnormal ophthalmologic examinations at the time of diagnosis. Only 4 patients had documented evidence of progressive disease prior to the institution of therapy. No patient had evidence of progressive disease following therapy. Four patients had radiologic evidence of tumor shrinkage and 2 patients had definite improvement in vision. There was only minimal toxicity. In conclusion, carboplatin is a safe and effective treatment for OPT in children with NF-1. However, as disease stabilization of NF-1 associated OPT often occurs following clinical presentation, the clinician should document tumor progression or visual deterioration prior to the institution of therapy.

Antineoplastic Agents↗

Evidence that some oligodendrocyte progenitors in the developing optic pathway express the plp gene.

DM-20, a product of the proteolipid protein (plp) gene, has been demonstrated in the spinal cord of the mouse embryo as early as embryonic day 12 (E12) in certain cells, some of which are identifiable as oligodendrocyte progenitors. The present work uses optic pathways of rat and mouse as well-characterized systems for the study of gliogenesis. plp gene expression was monitored with a combination of reverse transcriptase polymerase chain reaction, in situ hybridization, and immunostaining with antibodies to different PLP peptide sequences, combined with O-2A lineage markers. In tissue sections, hybridizing cells were detected initially in the proximal optic tracts between E18 and birth and thereafter progressively in the chiasm and optic nerves. Small unbranched cells expressing DM-20 but not myelin basic protein (MBP) and probably representing progenitors were detectable by immunostaining in similar locations. With increasing postnatal ages, cells representing maturing oligodendrocytes which co-label for PLP and MBP are present in the optic pathways. In vitro analysis of freshly dissociated cells from premyelinated optic nerve demonstrated that the plp gene is expressed in some O-2A progenitor cells as well as mature oligodendrocytes. We also present evidence that increase in expression of the plp gene along the O-2A lineage differentiation is not progressive but that downregulation at the proligodendroblast (O4+/O1-) stage probably occurs. We suggest that progenitors express the dm-20 isoform while oligodendrocytes express predominantly the plp isoform. Not all progenitors express the plp gene at the times studied, indicating that the presence of DM-20 is either transitory in individual cells or that only a sub-population is involved. The function of DM-20 at this early stage of the oligodendrocyte lineage has yet to be determined.

Animals↗

Late-onset optic pathway tumors in children with neurofibromatosis 1.

Identification of new optic pathway tumors (OPTs) and progression of pre-existing OPTs in children with neurofibromatosis 1 (NF1) have been reported infrequently after age 6. The authors present eight children with NF1 (mean age 12.2 years) seen in three NF1 centers who had either late-onset (four of eight) or late-progressive (seven of eight) OPT. Continued monitoring of individuals with NF1 into adulthood for the development of OPTs and for progression of known OPTs is warranted.

Adolescent↗

Pediatric tumors of the orbit and optic pathway.

We present an overview of the treatment and clinical outcome of 30 pediatric patients with orbital and optic pathway tumors cared for in our center from 1991 to 2002. Follow-ups were available for 48 months on average. Eight of 14 gliomas of the optic nerve or pathway were subtotally resected via a pterional approach. Two were totally resected with transection of the optic nerve, 2 were only biopsied and 2 were observed. One of 4 optic nerve sheath meningiomas in patients with good visual acuity was subtotally resected with decompression of the optic canal. Two were totally resected with transection of the prechiasmal optic nerve and 1 was only biopsied. Four infectious intra-/extraconal lesions were biopsied (transconjunctival approach) and treated with antibiotics. Two vascular intra-/extraconal tumors (hemangiomas) were removed via a transconjunctival approach and a lateral orbitotomy. The following histologies only occurred once: dermoid cyst, aneurysmal bone cyst, eosinophilic granuloma, fibrous dysplasia, osteopetrosis and rhabdomyosarcoma. The spectrum of pathology in pediatric orbital tumors is wide and requires multidisciplinary treatment.

Adolescent↗

Study of visual evoked potentials in the assessment of the central optic pathways in leprosy patients.

We evaluated the possible involvement of central optic pathways (COP) in leprosy patients with visual evoked potentials, an easy, sensitive and reliable noninvasive method for evaluation of COP. In 37 patients with lepromatous leprosy and in 37 age-matched controls, we measured reversal pattern visual evoked potentials (RP-VEP) and nerve conduction parameters. The mean latency value of positive peak P100 in leprosy patients was significantly delayed compared to that of controls (patients, 108.02+/-9.61 ms in left eye and 108.23+/-8.51 ms in right eye; controls, 96.22+/-4.20 ms in left eye and 95.75+/-4.03 ms in right eye; p<0.05). Abnormally delayed P100 latency was recorded in 5 of 37 leprosy patients (13.5%). The mean amplitude of P100 latency in leprosy patients was smaller than that of controls (patients, 8.7+/-5.6 micro V in left eye and 9.5+/-4.8 micro V in right eye; controls, 10.7+/-4.6 micro V in left eye and 10.5+/-5.1 micro V in right eye), but this difference was not significant. No correlation was observed between abnormalities of RP-VEP and sensorimotor nerve conduction parameters. This study suggests that involvement of COP may develop in patients with lepromatous leprosy. RP-VEP measurement, which can be easily and rapidly performed in an EMG laboratory using standard equipment, can show these alterations.

Adult↗

[Parafoveolar scotomas in microinfarcts of the optic pathways (author's transl)].

Small parafoveolar scotomas in microinfarction of the optic pathways are often not demonstrated, or only inaccurately so, in conventional kinetic perimetry. By using Amsler's grid it is possible to determine accurately the shape and position of such visual field defects. Some remarkable variants of these scotomas are described.

Adult↗