正常人眼球直肌Pulley功能位置的动态磁共振成像研究

目的研究正常人眼球运动动态磁共振成像（MRI）4条直肌Pulley（滑车）的功能性位置。方法采用西门子公司Sonata1.5T超导型MRI扫描仪,应用眼球运动动态MRI技术,获取20名正常人（20个眼眶）眼球原在位及上转、下转、内转、外转20度时垂直于眶轴的眼眶冠状位MRI图像。以眼球中心为原点建立三维坐标系,应用ScionImage医学图像测量软件分别测量各层面眼球垂直转动时水平直肌、眼球水平转动时垂直直肌的横截面质心。根据各层面直肌横截面质心的坐标值建立直线回归方程,分别求得眼球垂直转动时内、外直肌径路及眼球水平转动时上、下直肌径路直线回归曲线斜率变化最大的一点,即为该直肌Pulley的功能性位置。对4条直肌Pulley相对于眼球中心的坐标值（X、Y）进行统计。结果内直肌Pulley位于眼球中心后4mm,内14.7mm,下0.3mm;外直肌Pulley位于眼球中心后8mm,外9.8mm,下0.3mm;上直肌Pulley位于眼球中心后6mm,内1.6mm,上11.5mm;下直肌Pulley位于眼球中心后6mm,内4.4mm,下12.7mm。结论应用眼球运动动态MRI技术,分析眼球转动时直肌径路的变化,可证实4条直肌Pulley的存在并确定其功能位置。     

Abnormal neuromuscular junctions in the lateral rectus muscle of wobbler mice

We have studied the lateral rectus muscles and neuromuscular junctions (NMJs) of abducens motoneurons in wobbler (wr/wr) mutant mice from 26 to 58 days of age. The muscles of wr/wr weighed about 70% of the weight of littermate controls and were composed of fiber types comparable to those of controls, as assayed by succinate dehydrogenase activity. The most obvious difference between wr/wr and control NMJs was a reduction in the length of the postjunctional membrane of wr/wr mice. The mutant muscle endplate membrane was only about 70% (6.58 micron) the length of control muscle regions (9.44 micron). There were no obvious differences at the light microscopic level in the distribution of acetylcholine (ACh) receptors at junctional regions or staining of acetylcholinesterase, as assayed with alpha-bungarotoxin binding or enzyme histochemistry. Indirect immunocytochemical studies using antibodies directed against the subunits of the ACh receptor failed to indicate an abnormal presence of immature receptors clustered at the NMJs of wr/wr mice. Our findings suggest that the formation or maintenance of normal postjunctional folds and the differentiation of receptors at the junctions are under independent control during development. Furthermore, the wobbler mutation may affect muscle cell differentiation as well as neuronal differentiation. This mutant mouse should prove a useful model for study of postjunctional fold formation and function.     

先天性麻痹性斜视眼肌的形态学改变及临床意义

目的研究先天性麻痹性斜视眼肌的形态学改变。方法将先天性麻痹性斜视12例18眼按年龄不同分为三组，将术中切下的眼外肌制成光镜和电镜标本进行比较。结果三组先天性麻痹性斜视的眼外肌均有病理性改变。年龄越大、病程越长，其病理改变越明显。结论先天性麻痹性斜视应早期手术治疗，以免眼外肌病理改变加重，影响双眼视功能恢复。     

Intraoperative lateral rectus electromyographic recordings optimized by deep intraorbital needle electrodes

ObjectiveWe demonstrate the advantages and safety of long, intraorbitally-placed needle electrodes, compared to standard-length subdermal electrodes, when recording lateral rectus electromyography (EMG) during intracranial surgeries.MethodsInsulated 25 mm and uninsulated 13 mm needle electrodes, aimed at the lateral rectus muscle, were placed in parallel during 10 intracranial surgeries, examining spontaneous and stimulation-induced EMG activities. Postoperative complications in these patients were reviewed, alongside additional patients who underwent long electrode placement in the lateral rectus.ResultsIn 40 stimulation-induced recordings from 10 patients, the 25 mm electrodes recorded 6- to 26-fold greater amplitude EMG waveforms than the 13 mm electrodes. The 13 mm electrodes detected greater unwanted volume conduction upon facial nerve stimulation, typically exceeding the amplitude of abducens nerve stimulation. Except for one case with lateral canthus ecchymosis, no clinical or radiographic complications occurred in 36 patients (41 lateral rectus muscles) following needle placement.ConclusionsIntramuscular recordings from long electrode in the lateral rectus offers more reliable EMG monitoring than 13 mm needles, with excellent discrimination between abducens and facial nerve stimulations, and without significant complications from needle placement.SignificanceLong intramuscular electrode within the orbit for lateral rectus EMG recording is practical and reliable for abducens nerve monitoring.     

眼外伤86例超声图像分析

目的：探讨眼外伤后超声图像及在临床诊断检查中的应用价值。方法：应用彩色多普勒显像仪高频探头直接眼部扫查，并与手术及其它眼科检查结果相印证。结果：共查眼外伤病例86人，病眼96只，超声诊断符合率为91.86％，漏、误诊率8.14％。各种损伤超声表现不同，对临床诊断及治疗方法有重要参考价值。结论：超声检查直观、迅速，并可重复检查，是眼外伤的重要检查方法之一，有较高的诊断价值。     

Evidence that the extraocular motor nuclei innervate monkey palisade endings

Palisade endings are found in the extraocular muscles (EOMs) of almost every mammalian species, including primates. These nerve specializations surrounding the muscle fiber insertion have been postulated to be the proprioceptors of the EOMs. However, it was recently demonstrated that palisade endings have a cholinergic nature, which reopened the question of whether palisade endings are motor or sensory structures. In this work, we examined whether the cell bodies of palisade endings lie in EOM motor nuclei by injecting an anterograde tracer, biotinylated dextran amine, into the abducens nucleus of a macaque monkey. Tracer visualization in the lateral rectus muscle was combined with choline acetyltransferase (ChAT) and α-bungarotoxin staining. Analysis of the samples was performed by conventional light microscopy and confocal laser scanning microscopy. About 30% of the nerve fibers innervating the muscle were tracer positive. These were ChAT positive as well. Tracer positive nerve fibers established motor contacts on singly and multiply innervated muscle fibers, which were confirmed by α-bungarotoxin staining. At the transition between muscle and distal tendon, we found palisade endings that contained tracer. Palisade endings exhibited the classic morphology: axons arising from the muscle extend onto the tendon, then turn back 180° and terminate in a cuff of terminals around an individual muscle fiber tip. This finding suggests that the cell bodies of palisade endings lie in the EOM motor nuclei, which complements prior studies demonstrating a cholinergic, and possibly motor, phenotype for palisade endings.     

共同性斜视患者眼外肌的光镜和超微结构研究

目的：研究共同性斜视患者眼外肌的组织形态学改变，为探讨斜视的发病机制奠定基础。方法：取60例共同性斜视患者和20例眼球摘除者的眼外肌组织标本，每例标本1／2行HE染色，光镜下观察；1／2标本作超薄切片，行透射电镜观察。结果：光镜下可见肌纤维排列疏松，肌纤维数量较少，间质成分多。小年龄组中可见萎缩变性的横纹肌细胞和排列混乱的肌纤维。而大年龄组则只有少量萎缩变性的肌细胞排列在大量胶原纤维结缔组织中。电镜下整个眼肌组织结构模糊，肌膜不完整，细胞内结构紊乱，细胞核固缩。且在大龄组中肌丝紊乱，肌纤维弯曲排列、间隙变宽以及空泡样改变更明显。结论：共同性斜视患者眼外肌有明显的改变，且病程越长，肌纤维的损害程度越重。从组织学的角度进一步完善了共同性斜视的发病机理。     

V型外斜视的手术治疗

目的探讨V型外斜视的临床特点和手术治疗效果。方法分析某院手术治疗的48例V型外斜视患者,观察手术前、后眼位的变化和双眼单视功能的情况。结果 V型外斜视的常见原因为斜肌功能异常,包括原发性下斜肌功能亢进、先天性上斜肌麻痹继发下斜肌功能亢进。手术治疗除2例欠矫外余均正位,疗效满意。结论 V型外斜视是一种常见的斜视类型,发病原因以斜肌功能异常为主,常合并水平斜视。斜肌手术是矫正V型外斜视的主要措施之一。     

Evidence for corrective effects of afferent signals from the extraocular muscles on single units in the pigeon vestibulo-oculomotor system

The role of extraocular muscle (EOM) afferent feedback signals in the control of eye movement is still controversial. We recorded from 106 single units in the vestibular nuclei, oculomotor nuclei and reticular formation of 80 decerebrate, paralysed pigeons. EOM afferents were stimulated by passive eye movement (PEM) during vestibular stimulation by sinusoidal oscillation in the horizontal plane. We found that EOM afferent signals profoundly modified the vestibular responses of 91 (86%) of the single units recorded. As well as using PEM to simulate eye movements similar to saccades, we moved the eye in a manner which mimicked the slow phase of the vestibulo-ocular reflex (artificial VOR, AVOR). We have found evidence that, as well as providing signals closely related to the parameters of eye movement, PEM alters the vestibular responses of cells during AVOR in a manner which suggests that EOM afferent signals may play a corrective role in the moment-to-moment control of eye movement in the vestibulo-ocular reflex.