SEARCH · PubMed Health

Results for “OPTIC PATHWAY”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 577 records · Page 32Linked to original sources

PubMed1988

Cell death in suboptic necrotic centers of chick embryo diencephalon and their topographic relationship with the earliest optic fiber fascicles.

The structural features of suboptic necrotic centers (SONCs) in the floor of the chick embryo diencephalon were studied. These necrotic areas were observed lateral to the prospective zone of the optic chiasm through developmental stages 14 to 24. The relationship between SONCs and the earliest optic fiber fascicles also was studied in an attempt to determine the possible significance of these cell death areas in the mechanism of optic pathway development. In SONCs, healthy neuroepithelial cells contain primary lysosomes and phagocytose fragments of dead cells. Discrete regions within the cytoplasm of some cells show electron-transparent vacuoles in contact with dense contents of ruptured lytic bodies. The cytoplasm of dying cells and dead cell fragments are notably electron dense, with numerous secondary lysosomes and electron-transparent vacuoles. These observations are interpreted on the assumption that after autophagic processes, condensation and fragmentation take place in dying cells of the SONCs. In the ventricular lumen adjacent to the SONCs, numerous more or less spherical bodies are observed that appear to be shed from the tip of the cells constituting the SONCs. Three different types of intraventricular bodies can be distinguished: loose, moderately dense, and highly dense. The first type appears to originate from apical portions of cells that undergo autolytic processes. Moderately dense fragments are interpreted as originating from dying cells in which the cytoplasm is undergoing condensation. Finally, highly dense intraventricular bodies appear to be fragments of dead cells that are shed into the ventricular lumen. SONCs separate the prospective area of the optic chiasm from lateral regions of the diencephalic floor. Extracellular spaces are poorly developed within the wall of the SONCs, whereas the neuroepithelium of the presumptive optic chiasm and regions located rostral and caudal to SONCs show abundant and extensive extracellular spaces. These are bounded by long marginal processes of neuroepithelial cells. Sagittal sections of embryonic heads at stages 22-24 reveal optic fiber fascicles penetrating the SONCs asymmetrically, as they are found only in its caudal half. These observations suggest that the SONCs function as doorways made of compact neuroepithelium, to be traversed by the earliest optic fibers before they reach the middle zone of the floor of the diencephalon through which they travel to the contralateral optic tract within large extracellular spaces.

Animals↗

PubMed2006

[Multidisciplinary use of contrast sensitivity].

BACKGROUND: Contrast sensitivity (CS) gives information about quality of different spatial frequency sent from sensory cells to the brain cortex through different pathways. METHODS AND RESULTS: From the age of 6 to 10 years average CS threshold was defined for each frequency. 3c/deg=1,82 (SD 0,13), 6 c/deg=2,04 (SD 0,14), 12 c/deg=1,74 (SD 0,15), 18 c/deg=l,29 (SD 0,11). In the age between 11 and 19 years following values were determined: 3c/deg=1,92 (SD 0,09), 6 c/deg=2,19 (SD 0,12), 12 c/deg=1,89 (SD 0,10), 18 c/deg=1,42 (SD 0,12). There was no significant difference between each frequency on CS curve. Average threshold for all frequencies was the 6th contrast level of circle in younger children and the 7th contrast level of circle in older. According to the standard deviations the threshold for all the frequencies was the 5th contrast level of circle in children from 6 to 10 and the 6th contrast level of circle in children older then 11. As the CS can be distorted by hidden form of anisometric amblyopia, proper correction of refractive error is essential. CS helps to detect hidden neuropathy in Graves disease or in Septo-optic dysplasia. Initial stages of demyelinisation of optic nerve in Multiple Sclerosis are manifested always by decrease of CS. This helps to evaluate the affection of the optic pathway and CNS in Alzheimer disease, in Parkinson's disease and schizophrenia. Decrease of CS goes along with retinopathy and with some forms of preretinopathy in Diabetes mellitus. Dynamic changes of CS can be related to treatment of several diseases including Cystic fibrosis, Chronic renal insufficiency, Neonatal hypothyreosis, Menopause or Osteoporosis. CONCLUSIONS: Author proves that CS can be reliably examined using the device CSV-1000 in children from the age of 6 years within the framework of multidisciplinary use.

Adolescent↗

PubMed1995

Intraocular motility, electrophysiological tests and visual fields in drug addicts.

The effects of drugs on intraocular motility, retina function and central pathways in a drug addicts population have been studied. The study group were made up of 15 drug addicts. Fifteen healthy subjects who had never used drugs acted as a control group. Refractive state, accommodation, tonometry, assessment of pupillary reflexes, campimetry, visual evoked cortical potential (VECP) and ERG were performed in all cases. All the subjects studied used heroine, 12 used cannabis and 12 used cocaine. Refraction was normal in all cases. Accommodation amplitude in normal subjects ranged from 8.5 to 11.5 D, and from 3.5 to 9.5 D in the drug addicts group. Tonometry indicated a tendency to lower intraocular pressure values. Direct and consensual pupillary reflexes were normal in eight subjects, but were sluggish in the rest. Campimetry showed relative and absolute scotoma in five subjects. VECP were found to be normal in two of the cases, moderately pathological in six and pathological in the remaining seven cases. As for the ERG, it showed non-specific altered traces in 11 cases. Accommodation amplitude was lower than normal in 20 eyes. The decrease of VECP with altered traces but with an increase of latency, seem to indicate the presence of an alteration in the optical pathway or in the cortical centres. The findings in ERG point out a decrease of amplitudes and an increase of latency in more than half the population studied.

Accommodation, Ocular↗

PubMed1999

MRI abnormalities in neurofibromatosis type 1 (NF1): a study of men and mice.

Hyperintense lesions on T2-weighted MR images of the brain, predominantly located in the basal ganglia, the brainstem and cerebellum, are a frequent finding in patients with neurofibromatosis type 1. Nature and significance of these lesions are still unknown so that the term 'unidentified bright objects' (UBOs) has been introduced to allow an unbiased description. We analyzed brain MRI scans of 31 children with definite diagnosis of neurofibromatosis type 1 according to the NIH criteria. High-intensity lesions on T2-weighted images were present in 86% of the patients. They did not correlate to other MRI findings such as optic pathway gliomas and were not indicative of intellectual impairment. Additionally, brain MR imaging of Nf1 knockout mice was performed to find out if similar abnormalities are present in this animal model. A total of 9 Nf1 knockout mice was examined on a dedicated animal MRI scanner at 4.7 Tesla but no evidence of high-signal intensity lesions on T2-weighted images was found. Therefore, the Nf1 mouse model seems to be unhelpful in providing further insights into the histological basis of hyperintense MRI abnormalities in NF1 patients.

Adolescent↗

PubMed2004

Ophthalmological manifestations in segmental neurofibromatosis type 1.

AIMS: To study the ophthalmological manifestations in individuals with the typical features of neurofibromatosis type 1 (NF1) circumscribed to one or more body segments, usually referred to as segmental NF1. METHODS: Visual acuity and colour tests, visual field examination, slit lamp biomicroscopy of the anterior segment, and a detailed examination of the retina by indirect ophthalmoscopy were performed at diagnosis and follow up in 72 consecutive subjects (29 males, 43 females; aged 1-64 years; mean age 14.6 years) seen at the university departments of paediatrics in Catania and Rome, Italy, during years 1990-2003, who had in restricted body areas: (1) typical pigmentary manifestations of NF1 (cafe au lait spots and freckling) only (n = 48); (2) NF1 pigmentary manifestations and neurofibromas alone (n = 2); (3) neurofibromas only (n = 15); and (4) plexiform neurofibromas only (n = 7). RESULTS: None of the 72 patients had Lisch nodules in the iris irrespective of age at eye examination or hypertelorism (a "minor" NF1 feature) and none developed typical associated ophthalmological NF1 complications. An additional child had an isolated optic pathways glioma (OPG), which behaved both biologically and radiographically as an NF1 associated OPG. CONCLUSIONS: This represents the first systematic study reporting on eye involvement in the largest series of individuals at different ages having segmental NF1. As one of the postulated mechanisms to explain segmental NF1 is somatic mosaicism for the NF1 gene (so far demonstrated only in two patients) the present findings could be explained either by the fact that the eye is too far from the mutated area with NF1 lesions in most cases or by the NF1 (or other "predisposing" or "cooperating") gene mutation restricted to too few cellular clones or to tissues embryologically different from the eye.

Adolescent↗

PubMed2002

Intracranial neoplasms in children with neurofibromatosis 1.

Neurofibromatosis 1 is associated with an increased risk for the development of benign and malignant tumors involving neural and non-neural tissues. Children as well as adults with neurofibromatosis 1 are affected. Central nervous system neoplasms represent a significant portion of these malignancies and appear primarily in children less than 10 years of age. Optic pathway gliomas and brainstem gliomas are the most common intracranial neoplasms found in neurofibromatosis 1, although there also is an increased incidence of other brain tumors in this population. The majority of these intracranial neoplasms are benign pilocytic astrocytomas, which may behave in a less aggressive manner than histologically identical tumors in non-neurofibromatosis 1 patients. Owing to the indolent nature of these tumors, conservative management with close follow-up is recommended. When intervention is required, conventional treatment with surgery, radiation, or chemotherapy has been used with variable results. The current challenge lies in understanding the pathogenesis of gliomas in neurofibromatosis 1, which may lead to the development of biologically directed therapies with less associated morbidity and mortality for neurofibromatosis 1 as well as non-neurofibromatosis 1 children.

Brain↗

PubMed1987

Are flash-evoked visual potentials useful for intraoperative monitoring of visual pathway function?

Flash-evoked visual potentials (VEPs) recorded from the scalp were used in a series of 35 patients with tumors along the visual pathway: 3 orbital tumors, 25 perisellar tumors, 4 intraventricular tumors, and 3 occipital lesions. Preoperatively, various combinations of impaired visual fields and visual acuity were observed in over 90% of the patients. A postoperative decrease in visual function was observed in 3 cases. Of the 25 perisellar lesions, 13 were operated through a standard frontotemporal craniotomy and 12 were operated through a transnasal-transsphenoidal approach. VEPs were highly susceptible to volatile anesthetics, and there was a significant incidence of spontaneous latency increases and amplitude decreases in a large number of patients. There was an unacceptably high number of cases with significant VEP alteration occurring without concomitant visual function change. During trepanation or the transnasal approach, a reversible potential loss was observed in 11 patients, a profoundly altered wave form was seen in 8 cases, and a loss of single peaks was observed in 15 patients. During dissection of the tumor, a reversible potential loss or a potential with unidentifiable peaks was found in 25 cases; however, the VEPs recovered during closure or in the recovery room. There was no correlation between intraoperative VEP changes and the postoperative changes in visual function. In only 1 patient with an insignificant postoperative decrease in visual acuity from 0.4 to 0.3 was there a concomitant intraoperative potential loss. The major conclusion of our findings is that light-emitting diode flash-evoked VEPs demonstrate intraoperative changes that appear too early and too prominently to be caused solely by manipulation of the optic pathways.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1997

[Neurofibromatosis type 1: a survey of 195 patients].

OBJECTIVE: To analyse symptoms and complications in patients with neurofibromatosis type 1 (NF1). All patients were examined in a multidisciplinary outpatient neurofibromatosis clinic during a period of 10 years. DESIGN: Retrospective. SETTING: Academic Medical Center, University Hospital Amsterdam, the Netherlands. METHOD: All data on 450 persons visiting the neurofibromatosis clinic were stored in a database. Data were collected on the results of dermatological, neurological, ophthalmological and general examinations and on family history. For this study the follow-up data of 196 patients with a definite diagnosis of 'NF1' were analysed. RESULTS: In childhood diagnosis NF1 is predominantly based on specific dermatological symptoms such as > 6 café-au-lait (CAL) spots and freckling and on the presence of characteristic ophthalmological signs as two or more Lisch nodules. In this study the frequencies of these symptoms were 98% (CAL). 92% (freckles), and 93% (Lisch nodules) respectively. The frequencies of well-known complications of this disorder are comparable with the literature findings. In this study we found optic pathway glioma (OPG) in 10%, macrocephaly in 36%, hydrocephalus in 5%, retardation in 14%, brain tumours in 5%, kyphoscoliosis in 13%. renal artery stenosis in 0.5% and neurofibrosarcoma in 0.5% of NF1 patients. In children the degree of severity of this disorder is less than in adults, demonstrating the progressive character of the disease. CONCLUSION: The diagnosis of 'NF1' can usually be made by dermatological and ophthalmological examination. In case of a definite diagnosis in childhood regular follow-up is recommended since severe complications, such as OPG and kyphoscoliosis, may occur specifically in childhood and adolescence. For adult patients determination of the degree of severity is essential for the decision whether or not they need regular follow-up; they should have their blood pressure measured annually.

Adolescent↗

PubMed1991

Imaging considerations of central nervous system manifestations in pediatric patients with neurofibromatosis type 1.

CT and MRI were used in a prospective study of the central nervous system (CNS) manifestations in 41 consecutive children with neurofibromatosis type 1 (NF-1). Gadolinium-DTPA was used in 15 patients. MRI was more effective than CT in delimiting the extension of the optic pathway glioma and in evaluating associated cerebral malformations. MRI visualized lesions generally undetected by CT, in the form of iso- or hyperintense foci with respect to the cerebral cortex in T2-weighted sequences. Well-delimited lesions of high signal intensity were observed in the globus pallidus (22 cases), the internal capsule (6 cases), corpus callosum (2 cases), anterior commissure (1 case) and semioval center (2 cases). Poorly defined hyper- or isointense areas were also observed affecting the cerebellar white matter (21 cases) and brain stem (17 cases). None of these lesions showed Gadolinium-DTPA enhancement, and were of no clinical significance. MRI has displaced CT in the initial diagnosis of patients with NF-1. Periodic annual MRI controls are only justified in patients with MRI changes to evaluate the progression or stabilization of the lesions.

Adolescent↗

PubMed1993

Management and outcome of low-grade astrocytomas of the midline in children: a retrospective review.

Low-grade astrocytomas of the midline of the brain can be difficult to manage because of their location. To evaluate treatment and outcome, we performed a retrospective study of children with midline low-grade astrocytomas admitted to The Hospital for Sick Children between 1976 and 1991. Eighty-eight children with biopsy-proven low-grade astrocytomas were identified. Forty-three tumors occurred in the optic pathways or hypothalamus, 13 in the thalamus, 7 in the pineal region, 14 in the midbrain, and 11 in the medulla. Patient follow-up ranged from 6 months to 15 years, with a mean of 4 years, 9 months. Overall outcome was related to the extent of resection, histological type, and location. Partial resections were often associated with involution of the tumor. Response to radiation was variable, and serious sequelae were observed. Thirty-three patients experienced recurrence, often with a good response to subsequent surgery; however, 12 of these patients died. The probability of survival was calculated to be 96% at 1 year, 91% at 5, and 80% at 10 years. Our study suggests that resection should be considered in all patients, both at presentation and recurrence.

Adolescent↗

PubMed2004

Recent advances in neurofibromatosis type 1.

PURPOSE OF REVIEW: The past decade, since the identification of the neurofibromatosis type 1 (NF1) gene, has witnessed great advances in our understanding of the role of the NF1 gene in the molecular pathogenesis of NF1-associated clinical abnormalities. The purpose of this review is to highlight recent advances in defining the molecular etiology of nervous system tumors and learning disabilities. RECENT FINDINGS: Neurofibromas and optic pathway gliomas result from NF1 inactivation in Schwann cells and astrocytes, respectively, but other cellular factors contribute to tumorigenesis. In addition, malignant progression of plexiform neurofibromas to malignant peripheral nerve sheath tumors requires additional genetic changes, including increased expression of growth factor receptors, molecules that are involved in tumor invasion and metastasis, and inactivation of critical cell cycle regulators. In addition, specific types of NF1 gene mutation may be associated with an increased risk for malignancy in individuals with NF1. SUMMARY: Research over the past few years has resulted in a detailed understanding of the molecular genetics of benign and malignant tumors affecting individuals with NF1 as well as the development of refined small animal models for these tumors. In addition, clinical studies have begun to define specific subpopulations of patients at risk for cancer and have identified targeted therapies for NF1-associated tumors, based on basic science research advances.

Adult↗

PubMed2000

Laser-induced afterimages in humans.

Afterimages induced by incoherent light sources have been studied as complex visual perceptions for over 200 years; however, individuals who have viewed a coherent source (a laser) on-axis have reported visual experiences unlike those observed for full-field flashes from incoherent sources. In the present study, 10 volunteers viewed all combinations of blue, green, and red laser light and background colors that matched the wavelengths of the laser sources (a total of 9 conditions). The bright focal (50 microm retinal irradiance diameter) 3-sec. exposures (approximately 9 log trolands-40% of the maximum permissible exposure level) given to the volunteers were administered as they performed a simulator tracking task. A 50/50 mirror (a mirror which reflected 50% of the laser beam into the optical pathway while allowing the 50% of the light from the visual scene to pass through the mirror) permitted simultaneous intrabeam viewing of the laser source and the scene. The volunteers were asked to report what they saw immediately after the laser was turned off and 1-min postexposure. The immediate reports indicated that the image they observed was the same color as the laser source and not the complementary color. Also, the images were of ten surrounded by well-defined borders and, regardless of laser's or background's col or, were generally red. One minute following presentation of the laser light the images seen were predominantly purple, dark or no longer present; however, the edge color when present generally appeared red. The immediate appearance of the images was inferred to be neural in nature and not photochemical. These results suggest the properties of the laser source, i.e., coherency, monochromaticity, and the laser's capacity to place an intense beam of light in a small retinal area, all contributed to the unique appearance of the postflash images.

Afterimage↗

PubMed2001

The clinical value of ophthalmic electrodiagnosis in children.

A group of 113 children with poor vision who had been referred to the Electrodiagnostic Clinic over a five year period were investigated for disease of the retina and optic pathway by electroretinography (ERG), electro-oculography (EOG) and visual evoked response (VER). The electrodiagnostic measurements were made using an automated system developed at Christchurch Hospital. The results of these investigations confirmed the clinical value of ophthalmic electrodiagnosis both as an aid in the diagnosis of these young patients and in determining their prognosis. In some cases it permitted an early detection of their condition. In addition the analyses of the ERG into rod and cone mediated responses helped to establish the diagnosis of hereditary retinal disorders and was particularly useful in the case of infants with nystagmoid movements of the eyes who were suspected of having poor vision. Interestingly 21 of the 113 patients were found to have functional visual loss. These patients complained of visual loss but subsequent examinations revealed their ocular findings, EOG, ERG and VER were all normal. The age of this functional visual loss group ranged from 7 to 15 years, with the average being 11.3 years (SD = 2.6 years). Furthermore they were a large group representing 32% of all the children between 7 and 15 years and in most cases were not happy at school.

Adolescent↗

PubMed2006

Second primary tumors in neurofibromatosis 1 patients treated for optic glioma: substantial risks after radiotherapy.

PURPOSE: Optic pathway gliomas (OPGs) are the most common CNS tumor in neurofibromatosis 1 (NF1) patients. We evaluated the long-term risk of second tumors in NF1-related OPGs after radiotherapy. PATIENTS AND METHODS: We reviewed 80 NF1 OPG patients from two NF1 clinics to evaluate the long-term risk of developing subsequent nervous system tumors, with or without radiotherapy. RESULTS: Fifty-eight patients were assessable for second tumors. Nine (50%) of 18 patients who received radiotherapy after their OPGs developed 12 second tumors in 308 person-years of follow-up after radiotherapy. Eight (20%) of 40 patients who were not treated with radiotherapy developed nine tumors in 721 person-years of follow-up after diagnosis of their OPGs. The relative risk of second nervous system tumor after radiotherapy was 3.04 (95% CI, 1.29 to 7.15). CONCLUSION: There is a significantly increased risk of second nervous system tumors in those NF1 patients who received radiotherapy for their OPGs, especially when treated in childhood. Thus radiotherapy should only be used if absolutely essential in children with NF1.

Adolescent↗

PubMed2003

Intensity-modulated radiation therapy (IMRT) for locally advanced paranasal sinus tumors: incorporating clinical decisions in the optimization process.

PURPOSE: Intensity-modulated radiotherapy (IMRT) plans require decisions about priorities and tradeoffs among competing goals. This study evaluates the incorporation of various clinical decisions into the optimization system, using locally advanced paranasal sinus tumors as a model. METHODS AND MATERIALS: Thirteen patients with locally advanced paranasal sinus tumors were retrospectively replanned using inverse planning. Two clinical decisions were assumed: (1) Spare both optic pathways (OP), or (2) Spare only the contralateral OP. In each case, adequate tumor coverage (treated to 70 Gy in 35 fractions) was required. Two beamlet IMRT plans were thus developed for each patient using a class solution cost function. By altering one key variable at a time, different levels of risk of OP toxicity and planning target volume (PTV) compromise were compared in a systematic manner. The resulting clinical tradeoffs were analyzed using dosimetric criteria, tumor control probability (TCP), equivalent uniform dose (EUD), and normal tissue complication probability. RESULTS: Plan comparisons representing the two clinical decisions (sparing both OP and sparing only the contralateral OP), with respect to minimum dose, TCP, V(95), and EUD, demonstrated small, yet statistically significant, differences. However, when individual cases were analyzed further, significant PTV underdosage (>5%) was present in most cases for plans sparing both OP. In 6/13 cases (46%), PTV underdosage was between 5% and 15%, and in 3 cases (23%) was greater than 15%. By comparison, adequate PTV coverage was present in 8/13 cases (62%) for plans sparing only the contralateral OP. Mean target EUD comparisons between the two plans (including 9 cases where a clinical tradeoff between PTV coverage and OP sparing was required) were similar: 68.6 Gy and 69.1 Gy, respectively (p = 0.02). Mean TCP values for those 9 cases were 56.5 vs. 61.7, respectively (p = 0.006). CONCLUSIONS: In IMRT plans for paranasal sinus tumors, tradeoff values between OP toxicity and PTV coverage can be compared for different clinical decisions. The information derived can then be used to individualize the parameters within the optimization system. This process of determining clinical tradeoffs associated with different clinical decisions may be a useful tool in other sites.

Humans↗

PubMed2000

Gamma knife radiosurgery as a primary treatment for prolactinomas.

OBJECT: The purpose of this study was to estimate the efficacy of gamma knife radiosurgery (GKS) in controlling tumor growth and endocrinopathy associated with prolactinomas. METHODS: Between 1993 and 1997, 164 of 469 patients with pituitary adenomas treated by GKS harbored prolactinomas. The dose to the tumor margin ranged from 9 to 35 Gy (mean 31.2 Gy), and the visual pathways were exposed to a dose of less than 10 Gy. The mean tumor diameter was 13.4 mm. The mean follow-up time for 128 cases was 33.2 months (range 6-72 months). Tumor control was observed in all but two patients who underwent surgery 18 and 36 months, respectively, after GKS. Clinical cure was achieved in 67 cases. Clinical improvement was noted with a decrease in the hyperprolactinemia after GKS. Nonetheless, in 31 (29%) of 108 patients who were followed for more than 2 years no improvement in serum prolactin levels was demonstrated, although this could be normalized by bromocriptine administration after treatment. Nine infertile women became pregnant 2 to 13 months after GKS and all gave birth to normal children. There was no visual deterioration related to GKS. Five women experienced premature menopause. In these patients there was subtotal disappearance of the tumor and an empty sella developed. CONCLUSIONS: Gamma knife radiosurgery as a primary treatment for prolactinomas can be safe and effective both for controlling tumor growth and for normalization of prolactin hypersecretion. A higher margin dose (> or = 30 Gy) seemed to be associated with a better clinical outcome. Gamma knife radiosurgery may make prolactinomas more sensitive to the bromocriptine.

Humans↗

PubMed1977

Effects of aging on visual evoked responses.

The effects of aging of visual evoked responses (VER) and critical frequency of photic driving (CFPD) was studied in 74 volunteers aged 18 to 79. The amplitude of VER to pattern reversal stimulation did not vary with sex or age. The latencies of the first major negative and of the first major positive defection of the VER were significantly delayed (P less than .001) with advancing age. This increase of latency probably reflects a slowing of conduction velocity in the optic nerve or optic pathways or both. CFPD, defined as the highest frequency of photic driving response expressed in flashes per second, showed an inverse correlation, decreasing with age in older subjects. Critical frequency of photic driving is the electrophysiological counterpart of critical flicker fusion, which is known to decrease with advancing age. These data support the concept that aging influences the functions of specialized sensory systems.

Adolescent↗

PubMed1988

Evoked potentials in chronic inflammatory demyelinating polyneuropathy.

Eighteen patients with chronic inflammatory demyelinating polyneuropathy were studied with evoked potentials to assess for evidence of central nervous system demyelination. Both visual and brain-stem auditory evoked responses were obtained, and the results were compared with magnetic resonance imaging (MRI). An evoked potential was abnormal in nine of 18 patients, five of whom had central nervous system evidence of demyelination by MRI. Evoked potentials identified four patients with probable anterior optic pathway involvement that was not demonstrable by MRI. These findings continue to support that chronic inflammatory demyelinating polyneuropathy is associated with a central demyelinating disorder and more importantly emphasize the possibility of a common pathogenic mechanism in central and peripheral nerve demyelination.

Brain Stem↗