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51.
To evaluate various MRI criteria we studied a representative group of 149 consecutive patients below 50 years with acute monosymptomatic optic neuritis (AMON), a frequent first manifestation of multiple sclerosis (MS). The presence, number, size, and localization of areas of increased signal (AIS) on T2-weighted brain MRIs obtained at 1.5 T were described and compared with findings in 71 healthy persons aged 21–50 years without diabetes, cerebrovascular or neurologic diseases. MRI was performed within 2–145 days, median 16 days from onset of AMON and showed from 0 to 26 AIS, sized 2–30 mm, in 79 of 149 (53%) patients compared to 0–18 AIS, sized 2–12 mm, in 31 of 71 (44%) healthy persons. In patients, AIS were significantly more frequent in women than in men (χ2 = 4.67, p > 0.05). Periventricular AIS were revealed in 70 (47%) patients and in 14 (20%) healthy persons. Subcortical AIS were present in 5 (3%) patients and in 18 (25%) healthy persons. Infratentorial AIS were present in only 3 (2%) patients. The sensitivity and specificity of previously proposed diagnostic MRI criteria for MS were unsatisfactory in our group of patients and have previously only been validated in definite MS. We therefore constructed and tested four new sets of criteria. The set with the best relation between sensitivity (e.g. 41%) and specificity (e.g. 93%) was the following: presence of two or more AIS, of which at least one is periventricular or infratentorial, combined with the absence of subcortical AIS. These criteria are recommended for patients with AMON and might be used in other patients with possible or probable MS.  相似文献   
52.
面肌痉挛显微血管减压术的诱发肌电图监测和评估   总被引:1,自引:0,他引:1  
目的:探讨面神经诱发肌电图在显微血管减压(MVD)术中、术后对面肌痉挛治疗效果的监测和评估。方法:对26例典型面肌痉挛病人、探讨在MVD术前、术中、术后,经皮刺激痉挛侧(手术侧)面神经下颌缘支,记录诱发同侧眼轮匝肌肌电位(MD-OC反应)变化,并以正常侧作对照检查。结果:26例术前均记录到痉挛侧MD-OC反应,在术中操作不同阶段,21例均见MD-OC反应消失。术后1周~3个月随访复查21例中,12例痉挛完全消失,MD-OC反应不复存在,9例症状明显或部分减轻,但有4例再记录到MD-OC反应。另5例术中,术后均记录到MD-OC反应,症状未有改善。结论:面神经诱发肌电图运用于MVD术中监测和预后判断,可改善和提高面肌痉挛的治愈率。  相似文献   
53.
We studied nine cases of retrobulbar neuritis with confirmed multiple sclerosis and six cases of optic atrophy from other causes. Pattern and focal electroretinograms (macular ERGs) were recorded with high (400 cd/m2) and low (40 cd/m2) intensity stimuli. Contrast sensitivity was also measured with a simple printed test.Luminance was not markedly important. High spatial frequency contrast sensitivity was significantly correlated with pattern ERG amplitude. Pattern and focal ERG amplitude ratio was usually reduced, but the effect was not correlated with contrast sensitivity or large enough to be useful clinically.In optic atrophy the pattern ERG (PERG) was clearly more severely reduced than the focal ERG (FERG). In retrobulbar neuritis both ERGs were equally and more severely reduced even though the visual losses were less. In unilateral cases the PERG increased then decreased after the initial attack, as previously described (Arden et al., 1982). The results suggest that retinal layers beyond the ganglion cells may be affected in retrobulbar neuritis, but proximally generated, pattern-specific ERG components are selectively lost in optic atrophy.  相似文献   
54.
Acute unilateral facial paralysis is usually a benign neurological condition that resolves in a few weeks. However, it can also be the source of a transient or long-lasting severe motor dysfunction, featuring disorders of automatic and voluntary movement. This review is organized according to the two most easily recognizable phases in the evolution of facial paralysis: (1). Just after presentation of facial palsy, patients may exhibit an increase in their spontaneous blinking rate as well as a sustained low-level contraction of the muscles of the nonparalyzed side, occasionally leading to blepharospasm-like muscle activity. This finding may be due to an increase in the excitability of facial motoneurons and brainstem interneurons mediating trigeminofacial reflexes. (2). If axonal damage has occurred, axonal regeneration beginning at approximately 3 months after the lesion leads inevitably to clinically evident or subclinical hyperactivity of the previously paralyzed hemifacial muscles. The full-blown postparalytic facial syndrome consists of synkinesis, myokymia, and unwanted hemifacial mass contractions accompanying normal facial movements. The syndrome has probably multiple pathophysiological mechanisms, including abnormal axonal branching after aberrant axonal regeneration and enhanced facial motoneuronal excitability. Although the syndrome is relieved with local injections of botulinum toxin, fear of such uncomfortable contractions may lead the patients to avoid certain facial movements, with the implications that this behavior might have on their emotional expressions.  相似文献   
55.
There are relatively few papers which prove that one nerve anastomotic agent for the facial nerve is superior to any other. Previous experiments on the division and anastomosis of the facial nerve have failed to consider the indeterminate variables involved, i.e. operator variability, controls and the reaction of the materials on normal nerve tissue. In this experiment, a variety of anastomotic agents were tested to see if the anastomotic agents themselves affected the extra-temporal facial nerve function. The absorbable suture, non-absorbable suture, glue and tube wrap used had no effect on normal nerve tissue or on the anastomosis of the sectioned facial nerve of the rat compared with simple laying together of the divided ends of the divided nerve.  相似文献   
56.
分析了1984~1993年期间47例经治的急性视神经炎患者。治疗应用地塞米松10mg、青霉素480万u静脉点滴7天,随后减量。结果治愈35例(74.47%),好转6例(12.76%),无效2例(4.26%),转院及自动出院各2例。47例中11例治疗效果不好者行筛窦开放术后,视力逐渐恢复正常,显示筛窦开放术有其临床实用价值。  相似文献   
57.
Serotoninergic fibers have been reported in both the abducens and facial nuclei of the cat. Furthermore, serotoninergic dorsal raphe and oculomotor internuclear neurons occupy similar locations in the periaqueductal gray overlying the oculomotor and trochlear motor nuclei. To resolve the issue of whether these two populations of neurons overlap, serotoninergic fibers were assayed in the abducens and facial nucleus; then the morphologies and distributions of identified serotoninergic neurons and oculomotor internuclear neurons were determined. Both the abducens and facial nuclei contained varicosities labelled with antibody to serotonin, but a much higher density of immunoreactive fibers was present in the latter, especially in its medial aspect. Distinct synaptic profiles labelled with antibodies to serotonin were observed in both nuclei. In both cases, terminal profiles contained numerous small, predominantly spheroidal, synaptic vesicles as well as a few, large, dense-core vesicles. These profiles made synaptic contacts onto dendritic and, in the facial nucleus, somatic profiles that occasionally displayed asymmetric, postsynaptic, membrane densifications. Following injection of horseradish peroxidase into either the abducens or facial nuclei, double-label immunohistochemical techniques demonstrated that the serotoninergic and oculomotor internuclear neurons form two distinct cell populations. The immunoreactive serotoninergic cells were distributed within the dorsal raphe nucleus, predominantly caudal to the retrogradely labelled oculomotor internuclear neurons. The latter were located in the oculomotor nucleus along its dorsal border and in the adjacent supraoculomotor area. Intracellular injection of horseradish peroxidase revealed that oculomotor internuclear neurons have multipolar somata with up to ten long, tapering dendrites that bifurcate approximately five times. Their dendritic fields were generally contained within the nucleus and adjacent supraoculomotor area. In contrast, putative serotoninergic neurons were often spindle-shaped and exhibited far fewer primary dendrites. Many of these long, narrow, sparsely branched dendrites crossed the midline and extended to the surface of the cerebral aqueduct. In the vicinity of the aqueduct they branched repeatedly to form a dendritic thicket. The axons of the intracellularly stained serotoninergic neurons emerged either from the somata or the end of a process with dendritic morphology, and in some cases they produced axon collaterals within the periaqueductal gray. Thus the oculomotor internuclear and serotoninergic populations differ in both distribution and morphology.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
58.
To describe special facial features of children with Williams syndrome in China by using method of three‐dimensional craniofacial anthropometry. Using three‐dimensional stereo photogrammetric device, 14 craniofacial anthropometric measurements were performed and five indices were calculated in 52 children with Williams syndrome and 208 age and sex matched controls of Han Chinese ethnicity. Except intercanthal width, mouth breadth, morphological face height, nasal height‐breadth index, nasal breadth‐depth index, morphological ear index, the Williams syndrome group under 3 years old were smaller than the control group in the other 12 variables. Compared with the control group, the Williams syndrome group aged 3–5 years old had smaller biocular breadth, nasal length, nasorostral angle, bitragal breadth, ear width, morphological ear index and face depth. The Williams syndrome group aged above 6 years old had smaller biocular breadth, nasal breadth, bitragal breadth, ear width, ear length and face depth than the control group. The craniofacial variability index of the Williams syndrome group was greater than the control group. Greater variation was found among children with Williams syndrome than normal in China, specifically at eye, nose, ear and face shape, which demonstrate the usefulness of three‐dimensional stereo photogrammetric analysis in supporting accurate diagnose of the patient with Williams syndrome.  相似文献   
59.
This study examines interpopulation variations in the facial skeleton of 10 modern human populations and places these in an ontogenetic perspective. It aims to establish the extent to which the distinctive features of adult representatives of these populations are present in the early post natal period and to what extent population differences in ontogenetic scaling and allometric trajectories contribute to distinct facial forms. The analyses utilize configurations of facial landmarks and are carried out using geometric morphometric methods. The results of this study show that modern human populations can be distinguished based on facial shape alone, irrespective of age or sex, indicating the early presence of differences. Additionally, some populations have statistically distinct facial ontogenetic trajectories that lead to the development of further differences later in ontogeny. We conclude that population-specific facial morphologies develop principally through distinctions in facial shape probably already present at birth and further accentuated and modified to variable degrees during growth. These findings raise interesting questions regarding the plasticity of facial growth patterns in modern humans. Further, they have important implications in relation to the study of growth in the face of fossil hominins and in relation to the possibility of developing effective discriminant functions for the identification of population affinities of immature facial skeletal material. Such tools would be of value in archaeological, forensic and anthropological applications. The findings of this study underline the need to examine more deeply, and in more detail, the ontogenetic basis of other causes of craniometric variation, such as sexual dimorphism and hominin species differentiation.  相似文献   
60.
Angelman syndrome (AS) is caused by several genetic mechanisms that impair the expression of maternally‐inherited UBE3A through deletions, paternal uniparental disomy (UPD), UBE3A pathogenic variants, or imprinting defects. Current methods of differentiating the etiology require molecular testing, which is sometimes difficult to obtain. Recently, computer‐based facial analysis systems have been used to assist in identifying genetic conditions based on facial phenotypes. We sought to understand if the facial‐recognition system DeepGestalt could find differences in phenotype between molecular subtypes of AS. Images and molecular data on 261 individuals with AS ranging from 10 months through 32 years were analyzed by DeepGestalt in a cross‐validation model with receiver operating characteristic (ROC) curves generated. The area under the curve (AUC) of the ROC for each molecular subtype was compared and ranked from least to greatest differentiable phenotype. We determined that DeepGestalt demonstrated a high degree of discrimination between the deletion subtype and UPD or imprinting defects, and a lower degree of discrimination with the UBE3A pathogenic variants subtype. Our findings suggest that DeepGestalt can recognize subclinical differences in phenotype based on etiology and may provide decision support for testing.  相似文献   
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