四种镍钛正畸弓丝表面微观结构的改变

背景：镍钛弓丝的腐蚀表现与其生物安全性及摩擦性能有着密切的关系，国外关于此方面的研究较多，但结果不完全一致。 目的：了解不同品牌镍钛弓丝的抗腐蚀性。 设计、时间及地点：对比观察实验，于2008-09/12在新疆医科大学基础医学院科研中心实验室和电镜室完成。 材料：北京圣玛特科技有限公司(SMT)、深圳市速航科技有限公司(SH)、3M Company U.S.A(3M)、托博正畸器械(无锡)有限公司(TP)生产的热激活型镍钛合金矫形丝，型号为上颌卵圆形。 方法：配制人工唾液并调节pH值分别为4.0及6.75，剪取4种不同品牌的镍钛弓丝末端较直的部分放入人工唾液中，并保持温度在37 ℃。 主要观察指标：分别于浸泡1，7，28 d时取出样本，使用扫描电镜对样本的表面结构进行观察。 结果：上述4种品牌的的镍钛弓丝经过浸泡后，表面结构均发生了不同程度的改变，其中SL、SMT组的改变程度较3M、TP组明显。各品牌在pH 4.0人工唾液中的改变程度大于pH 6.75，并随着浸泡天数的增加表面结构的变化越明显。 结论：①酸性环境加速了镍钛弓丝的腐蚀，并随着浸泡天数的增加腐蚀改变的程度越大。②不同品牌的镍钛弓丝所表现出的腐蚀形式和程度不完全相同。     

钛合金表面纳米结构对钙磷矿化物体外沉积及成骨细胞矿化功能的影响

背景：通过改变金属材料置入假体表面物理性质，可以增强细胞的成骨性能，表面纳米化处理是当前研究的一个重要方向。 目的：通过测定纳米钛合金和未处理微米钛合金表面钙磷沉积量及成骨细胞在两种材料表面的钙化功能，评估材料表面纳米结构对钛合金生物相容性的影响。 方法：采用表面机械研磨处理(SMAT)制备了表面纳米结构的Ti6Al4V钛合金，将钛合金表面的微米级晶粒转变为纳米尺寸的晶粒。实验分为微米合金和纳米合金组，将试样浸入模拟体液中浸泡21 d。分离新生乳鼠颅盖骨成骨细胞进行培养，将其分别接种到纳米表面和微米表面钛合金上进行共培养14 d。观察两组合金表面粗糙度、润湿角、材料表面钙磷沉积量、成骨细胞钙结节形成的情况。 结果与结论：①基于SMAT技术的表面纳米钛合金表面得到粗糙表面，其组成的晶粒则为纳米量级，表面粗糙度(Ra)由 132.5 nm增加到4019.3 nm；接触角由57.26°减小到22.4°；表面能由39.4 mJ/m2增加到67.3 mJ/m2。②在无成骨细胞的模拟体液中沉积7，14，21 d之后，纳米Ti6Al4V合金表面的钙磷元素沉积量显著增加。③纳米钛合金表面形成的钙结节面积显著大于微米钛合金表面，培养14 d后前者约为后者的3倍。结果提示，表面纳米钛合金能明显促进成骨细胞的矿化，并增加表面钙磷的沉积，具有较好的生物相容性。 关键词：纳米结构；Ti6Al4V；成骨细胞；矿化；钙磷沉积；纳米生物材料 doi:10.3969/j.issn.1673-8225.2010.12.016     

镀金技术对医用镍铬合金表面性能的影响

摘要 背景：镍铬合金长期存在于体液这种特殊的电解质环境中,镍离子析出现象尤为明显,不仅可能导致过敏反应,还有一定的致畸和致癌作用。对镍铬合金表面进行修饰,从理论上可以有效提高镍铬合金安全性。 目的：观察医用镍铬合金表面经无氰镀金处理前后,镍离子析出量的变化。 方法：将50件镍铬合金试件随机分为镍铬合金无氰镀金组与镍铬合金组。分别浸泡于pH 4.8与pH 7.0的人工唾液中一定时间后,利用AA-240型原子吸收光谱仪进行镍离子析出量检测。 结果与结论：无氰镀金后的镍铬合金在pH 4.8与pH 7.0的人工唾液环境中镍离子析出量均有所下降,与未镀金处理的镍铬合金比较,差异具有显著性意义(P < 0.05)。结果表明无氰镀金后镍离子析出量降低,医用镍铬合金表面稳定性有所提高。 关键词：镍铬合金;无氰镀金;镍离子;金属腐蚀;人工唾液 doi:10.3969/j.issn.1673-8225.2010.42.017     

电化学沉积含锂离子的钙磷涂层

背景：低浓度锂离子（4 mmol/L）可以激发Wnt基因信号，促进人间充质干细胞的有丝分裂和增殖。 目的：拟通过电化学共沉积，在钛合金表面制备含锂离子的钙磷涂层，观察其对MG63类成骨细胞贴附和增殖的影响。 设计、时间及地点：对比观察实验，2007-03/12在武汉大学口腔医学院口腔生物医学工程教育部重点实验室完成。 材料：钛合金片由陕西省宝鸡市德昌钛镍有限公司提供，加工成直径1 cm，厚1 mm圆片；LiCl为美国EMD Biosciences公司产品。MG63细胞由武汉大学典型培养物收藏中心提供。 方法：将0.5 g/L和5 g/L两种浓度的锂离子加入钙磷电解液中，在电场作用下于阴极钛合金片上制备钙磷复合涂层。采用扫描电镜观察涂层的表面形貌，X射线衍射和红外光谱确定涂层的组成，测量涂层中锂离子含量和涂层厚度，监测锂离子在仿生理体液中的释放曲线，采用细胞计数试剂盒了解MG63类成骨细胞在涂层表面的贴附和增殖情况。 主要观察指标：钙磷涂层的表面形貌、组成、厚度、锂离子含量和MG63类成骨细胞在涂层表面的贴附和增殖情况。 结果：锂离子的加入抑制了钙磷涂层的沉积，随着电解液中锂离子浓度的增加，钙磷涂层表面逐渐变得平整，晶粒变小，涂层中磷酸八钙含量增加，磷灰石含量减小，同时涂层厚度降低。当电解液中含0.5 g/L LiCl时，涂层中锂离子含量为 2.2 mg/g，当电解液中含5 g/L LiCl时，涂层中锂离子含量为5.5 mg/g。在pH 7.3时，锂离子在仿生理体液中呈“爆发式”溶解曲线，约0.5 h后即达到溶解总量的70%~80%，24 h后，其溶解逐渐达到饱和状态。MG63细胞在含锂离子的涂层表面贴附量增多，当电解液中含5 g/L LiCl时，MG63细胞在涂层表面第3天的倍增指数显著性增高（P < 0.05）。 结论：可以通过电化学沉积在钙磷涂层内复合锂离子，并可能因此增强了涂层的生物活性。     

4002/不同表面粗糙度的钛合金与牙本质之间粘结强度的比较研究（英文他译）

研究不同表面粗糙度的钛合金与牙本质之间拉伸粘结强度的差别。方法：钛合金铸件30个,随机平分为6组,分别用60目、80目、100目、150目、240目、320目的碳化硅砂纸打磨粘结面,测定打磨后铸件的表面粗糙度。收集一个月内拔除的人新鲜离体磨牙30颗,在流水冲洗下去除牙合 面釉质暴露浅层牙本质,随机平分为6组,依次用320目、400目、600目碳化硅水磨砂纸打磨牙本质面。利用Ketac TM Cem Easymix玻璃离子水门汀（美国3M公司）将打磨后的钛合金铸件和牙本质粘结,经37°C恒温水浴24h后,用万能试验机检测其微拉伸粘结强度,然后在扫面电镜下观察粘结断面。结果：经80目碳化硅砂纸打磨后的钛合金铸件组和牙本质之间的粘结强度最大（6.65MPa）,与其他组相比差别具有显著性（p<0.05）,该组铸件的表面粗糙度为2.69±0.32μm,扫描电镜观察显示,该组粘结断面发生在牙本质与粘结剂之间。结论：不同的表面粗糙度对钛合金与牙本质之间的粘结强度有影响,表面粗糙度为2.69±0.32μm的钛合金与牙本质之间的粘结强度最大。     

含铜宫内节育器铜丝和+铜套在模拟宫腔液中的腐蚀*☆

背景：含铜宫内节育器有较好的避孕效果是铜在宫腔内腐蚀而释放出铜离子的结果，因而铜的腐蚀行为直接关系到含铜宫内节育器能否安全、有效、长期使用。 目的：观察宫内节育器铜管与铜丝在模拟宫腔液中浸泡后的腐蚀形貌。 设计、时间及地点：体外观察实验，于2008-10/12在中国药品生物制品检定所与北京科技大学电镜室完成。 材料：实验使用天津医疗器械厂生产的健美牌宫内节育器，型号为TCu380A和TCu220C。 方法：分别将相同表面积的含铜宫内节育器铜丝及铜套浸在模拟宫腔液中，定期换液。取未浸泡前，浸泡10，30，60 d的样品，用扫描电镜观察表面形貌。 主要观察指标：样品表面形貌。 结果：未浸泡铜丝上有拉痕，腐蚀反应的产物沉积在铜丝表面，从而TCu380A开始浸泡阶段暴释效应明显；而铜套的腐蚀过程出现许多蚀坑，蚀坑刚出现时，增大铜表面积，随后腐蚀反应的产物沉积在表面，从而TCu220C的铜离子的释放速率开始时增加，后期下降。 结论：含铜宫内节育器的铜套与铜丝浸泡在模拟宫腔液中的初期，腐蚀形貌存在明显差异。铜丝表面为均一的、密集的小的蚀坑，而铜套表面为分布不规则的大的蚀坑。     

模拟人体口腔环境中比较镍钛弓丝的腐蚀性能

背景：口腔材料在行使功能时，处于非常复杂的电解质环境，会发生各种形式的生物环境腐蚀，导致金属离子的析出。现代金属腐蚀理论认为金属及其合金的生物学效应取决于材料在应用时被释放或溶出到生物体内的元素特性和浓度。 目的：考察两种临床常用正畸镍钛弓丝的腐蚀性能。 方法：采用光学显微镜及元素成分分析测试镍钛合金弓丝的显微组织形态和组成，应用循环极化法在模拟人体口腔环境中对比两种镍钛弓丝的腐蚀性能，把两种弓丝浸泡在37 ℃的人工唾液中1个月后观察分析其表面形貌。 结果与结论：两种弓丝的显微组织和组成存在差异。A弓丝的腐蚀电位高于B弓丝，而A弓丝的腐蚀电流相对较小，A弓丝表面形成的氧化膜更加稳定，对基体的保护效果更好。A弓丝的耐腐蚀性能相对较高，弓丝的组织、组成差别及其加工工艺是影响合金弓丝抗腐蚀性能的重要因素。     

钛及钛合金表面生物活性改性及效果评价

背景：钛及钛合金是常用的医用生物材料,其具有良好的生物相容性,但其缺乏骨诱导的能力,其与骨组织之间只是一种机械性的接触。 目的：概述钛及其合金表面生物活性改性的方法及对于改性后效果评价的方法,为临床应用提供参考。 方法：应用计算机检索PubMed数据库,CNKI数据库中关于钛及钛合金表面生物活性改性的文章,英文检索词为“titanium,titanium alloy,coating,bioactivity,bone”,限定文献语言种类为“English”,中文检索词为“钛,钛合金,涂层,活性改性,骨组织”,限定文献语言种类为中文。 结果与结论：在表面生物活性改性的方法中,主要有等离子体喷涂法、微弧氧化法、溶胶-凝胶法及生物仿生法等。钛及钛合金表面的活性涂层已经从单一涂层发展到复合涂层、梯度涂层、纳米梯度涂层,同时多种改性技术的联合运用,也让钛及其合金表面的涂层性能更加完善。对于改性后的效果研究,主要以模拟体液浸泡、成骨细胞培养,亲骨荧光素染色及放射影像学观察为主。对钛及钛合金进行表面生物活性改性是个复杂的工程,既要考虑改性后涂层骨诱导的能力,同时也需要兼顾涂层与基体结合强度的问题。只有对涂层组层进一步研究并利用多种技术对钛及钛合金表面进行处理,才能使其表面的涂层活性更高,并且结合牢固。     

计算机辅助设计与钛合金精密铸造的颅骨缺损个体化修复体

背景：现代的颅骨成形不应仅停留在修补缺损恢复颅腔完整性的基础上，而应达到颅骨表面解剖重建，兼顾形态和功能。目前常规使用的颅骨缺损修复方法存在许多缺限与不足，特别在修复巨大、复杂部位的缺损更加困难。 目的：探讨利用CT数据、CAD、快速成型技术结合现代铸造工艺，以医用钛合金为材料颅骨缺损个体化修复体原位辅助设计与精密铸造的方法。 方法：以成年山羊为实验对象，建立颅骨缺损的动物模型，CT连续薄层容积扫面获取原始数据，经数据处理后三维建模，在surfacer9.0中运用原位完全贴合、交互式屏幕显示法设计修复体三维模型。将设计的个性化修复体三维曲面模型数据输入快速成型机，完成修复体的原型制造。以钛合金为材料，运用熔模铸造法制作个体化修复体。 结果与结论：通过CT原始数据的获取、图像处理三维重建、原位完全贴合法个体化计算机辅助设计、修复体快速原型制造、钛合金精密铸造成型过程完成个体化修复体制作。修复体与缺损具有极强的适配性，吻合良好。结果说明基于CT数据、计算机辅助设计、快速成型技术为解决临床医学中长期困扰的“量身定作”问题提供了有效的方法和制作手段，简化了手术操作，缩短了手术时间，降低了手术风险，外形功能恢复满意。     

CT扫描计算机模拟重建定位定向毁损治疗帕金森病

目的：研究CT扫描结合计算机辅助计算定位，术中电生理验证确定丘脑腹外侧核（VL）苍白球腹后外侧部（VPLP）在治疗帕金森病（PD）中的作用。方法：对520例PD病人582次手术，CT扫描后，将 扫描资料在计算机中确定阴性靶点后，行电生理验证，再调整后的结果行射频毁损结果：CT扫描结合计算机模拟重建定位，准确率达95．2％，电生理纠偏率4．8％。结论：CT扫描计算机模拟重建定位准确率很高，但术中电生理验证仍有必要。     

The Visual Association Test-Extended: a cross-sectional study of the performance validity measures

Objective: Given the hazards of knowledge about performance validity tests (PVTs) being proliferated among the general public, there is a continuous need to develop new PVTs. The purpose of these studies was to validate the newly developed Visual Association Test-Extended (VAT-E). Method: The VAT-E consists of 24 pairs of line drawings; it is partly based on Green’s Word Memory Test (WMT) paradigm. In study 1, we compared VAT-E total scores of healthy controls (n = 226), patients with mild cognitive impairment (MCI) (n = 76), patients with Alzheimer’s disease (AD) (n = 26), and persons instructed to feign memory deficit (n = 29). In study 2, we compared litigating patients classified by Slick’s criteria as Malingering of Neurocognitive Dysfunction (MND) (n = 26) or non-MND (n = 67). In addition, we compared the VAT-E to the Test of Memory Malingering (TOMM) (study 1) and the WMT (study 2). Results: Results showed that the VAT-E differentiated patients with MCI (specificity 93–100%) or patients with AD (specificity 92–100%) from persons instructed to feign (sensitivity 86–100%). The VAT-E also differentiated MND from non-MND (sensitivity 54%, specificity 97%). The VAT-E was in perfect agreement with the TOMM in classifying healthy controls and persons instructed to feign, and it was in moderate agreement with the WMT in classifying non-MND and MND. Conclusion: Preliminary evidence shows that the VAT-E may be a useful PVT based on the ability to differentiate between those with genuine memory impairment, persons instructed to feign memory impairment, and a group suspected of malingering cognitive deficits.     

Diagnostic Difficulties and Treatment Implications

Summary: Differentiation between types of epileptic seizures has been aided in recent years by the introduction of intensive neurodiagnostic techniques and the development of increasingly detailed classification systems. Paradoxically, these developments have not simplified the task of matching the appropriate antiepileptic drug to a particular seizure type. It is reasonable to assume that anticonvulsant drugs will have different effects on different types of seizures, but faulty, circular reasoning can enter the picture if one also assumes that responses of seizures to different drugs signify different seizure types. There are several examples of differential diagnoses that can fall prey to this problem, including the diagnosis between partial seizures with secondary generalization and generalized tonic-clonic seizures, and the diagnosis between complex partial seizures and absence seizures with automatisms, among others. Considerations of etiology in future classification systems can further complicate the problem: should one then choose an anticonvulsant drug on the basis of individual seizure type or on the basis of the type of epilepsy? Ramifications of this issue extend even to the drug approval process. Official sanction is not given for use of a drug for a seizure type not included in the original efficacy studies, even if later scientific evidence shows that seizure type to be related to a type that is included. New trials must be undertaken. These problems arise from how we choose to classify seizures.     

Cognitive Dysfunction Associated with Antiepileptic Drug Therapy

Summary: Epilepsy is frequently associated with cognitive dysfunction. However, the reasons for this correlation are unclear. Possible influential factors include patient age; duration, frequency, etiology, and type of seizures; hereditary factors; psychosocial issues; and antiepileptic drug (AED) therapy. Whereas many of these factors are beyond the physician's control, AED therapy is one element that can be addressed in treatment decisions by recognizing the potential cognitive effects of particular AEDs. For example, phenobarbital impairs memory and concentration; phenytoin affects attention, problem solving ability, and performance of visuomotor tasks. In contrast, carbamazepine may affect concentration, while valproate would appear to have minimal effects on cognition. Moreover, cognitive effects of AEDs are amplified with coadministration of multiple anticonvulsants (polytherapy). A review of studies on the cognitive effects of monotherapy with AEDs, as opposed to those of polytherapy, provides evidence that drug-related cognitive dysfunction can be reversed if patients are switched to a simpler therapeutic regimen. Future research should be directed toward developing reliable measures for assessing and monitoring cognition, and understanding the particular cognitive side effects of each AED. Physicians also need to revise their opinions about which side effects are "tolerable" for epileptic patients.     

Carbamazepine Efficacy in Adults With Partial and Generalized Tonic-Clonic Seizures

Summary: Carbamazepine and phenytoin are drugs of choice in initial monotherapy for adult partial and secondarily generalized tonic-clonic seizures. These designations reflect the results of the Veterans Administration Epilepsy Cooperative Study Group of 1985. An earlier comparative study of carbamazepine and phenytoin by Ramsay and associates found both drugs equally effective in controlling new-onset seizures. Among the advantages of carbamazepine is that it causes relatively few cognitive and dysmorphic side effects. Its disadvantages are its unavailability in parenteral formulation and its metabolic autoinduction. The latter must be compensated for by planned dosage increases to maintain therapeutic plasma steady-state levels during the first 2 or 3 months of treatment. Carbamazepine is judged a drug of choice in the treatment of these secondarily generalized tonic-clonic seizures, and the drug of choice in children, adolescents, and women susceptible to the dysmorphic side effects associated with other anticonvulsant agents.     

Etiologic and Preventive Aspects of Epilepsy in the Child–Bridging the Gap Between Laboratory and Clinic

Summary: Four broad categories of basic phenomena are pertinent to developing ways to prevent epilepsy. These include mechanisms of epileptogenesis, ictal initiation and temporary entrainment by the seizure discharge of normally functioning brain, seizure propagation, and control mechanisms that function both to restrain the cascade of epileptic events culminating in a seizure and to arrest the epileptic event and restore the interictal state. In newborns and children, hypoxia-ischemia is a major factor leading to epileptogenesis, and several schemes are proposed to classify, quantify, and prevent hypoxic-ischemic encephalopathy. Control mechanisms must be better understood in order to develop prophylactic recommendations for epilepsy, and an experimental model of "kindling antagonism" may increase our understanding of these. Programs of prevention of seizures in children will evolve only if basic researchers and clinicians work productively together to develop an adequate understanding of factors important in epileptogenesis and antiepileptogenic control mechanisms.     

Epilepsy and anomalies of neuronal migration: MRI and clinical aspects

Neuronal migration disorders are the result of disturbed brain development. In such disorders, neurons are abnormally located. In diagnosing these conditions, magnetic resonance imaging is superior to any other imaging technique. This enables us to improve our knowledge of the clinical correlates of neuronal migration. With reference to migrational disorder, a retrospective study of all 303 patients with epileptic seizures referred for magnetic resonance imaging during a 3-year period was performed, 13 patients (aged 12-41, mean age 27) were identified. They represent 4.3% of the entire study group. Of the patients with known epilepsy, 6.7% and of the mentally retarded, 13.7% had migrational disorders. Four patients had schizencephaly as the dominant finding, one was classified as hemimegalencephaly, 2 had isolated heterotopias, and 6 had localized pachy- and/or poly-microgyria. The clinical pictures are complex. Ectopias of grey matter are recognised foci of epilepsy, but from an epileptological and a clinical viewpoint little attention has been given to these disorders. The present study shows that malmigration is not rare in epilepsy patients, especially not in the mentally retarded.     

Predisposing and Causative Factors in Childhood Epilepsy

Summary: We review information from large studies of defined populations, examining the role of known factors and especially of prenatal and perinatal factors in contributing to nonfebrile seizure disorders of early childhood. We depend especially, but not exclusively, on the recently completed analyses from the Collaborative Perinatal Project of the National Institute of Neurological and Communicative Disorders and Stroke, the NCPP. About 4% of children in the NCPP who had at least one non-febrile nonsymptomatic seizure by the age of 7 years had a previous seizure during acute neurologic illness, such as meningitis or during the acute illness after trauma. Many such seizures should potentially be preventable. Of children with seizures, 10% had had a neonatal seizure and 13% had had a febrile seizure. Among the hundreds of prenatal and perinatal factors explored as predictors of childhood seizure disorders, the principal predictors identified were congenital malformations of the fetus, cerebral and noncerebral; family history of certain neurologic disorders; and neonatal seizures. In agreement with the British National Child Development Study, labor and delivery factors in the NCPP appeared to contribute very little to childhood seizure disorders. Maldevelopment, rather than damage at birth to an initially intact nervous system, appeared to be the more common mechanism. Most seizure disorders of early childhood remained unexplained by the large set of prenatal and perinatal characteristics examined.     

Anticonvulsant Drugs and Cognitive Function: A Review of the Literature

Summary: Alterations of cognitive function are separate from disturbances of behavior seen in association with epilepsy. The nature of the cognitive disability may to a certain extent depend on the seizure type. Partial seizures, mainly derived from a temporal lobe focus, impair memory tasks, while generalized seizures seem to have more effect on attentional abilities. A number of studies, reviewed in this paper, suggest that anticonvulsant drugs further impair cognitive function. Maximal impairments are seen in patients receiving polytherapy: rationalization of polytherapy improves cognitive abilities. Studies in children and adults have allowed differentiation of the effects of various commonly used antiepileptic agents. Maximal cognitive deficits are seen with. phenytoin, while phenobarbital and sodium valproate induce moderate disturbances, and carbamazepine seems relatively free from such toxicity. Further research is needed on the interrelationship between types of seizure disorders, types of anticonvulsant medications, and cognitive function.     

Classification of methods in transcranial Electrical Stimulation (tES) and evolving strategy from historical approaches to contemporary innovations

Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior to a contemporary resurgence in interest, variations of transcranial Direct Current Stimulation were explored intermittently, including Polarizing current, Galvanic Vestibular Stimulation (GVS), and Transcranial Micropolarization. The development of these approaches alongside Electroconvulsive Therapy (ECT) and pharmacological developments are considered. Both the roots and unique features of contemporary approaches such as transcranial Alternating Current Stimulation (tACS) and transcranial Random Noise Stimulation (tRNS) are discussed. Trends and incremental developments in electrode montage and waveform spanning decades are presented leading to the present day. Commercial devices, seminal conferences, and regulatory decisions are noted. We conclude with six rules on how increasing medical and technological sophistication may now be leveraged for broader success and adoption of tES.     

Treatment Considerations in Anticonvulsant Monotherapy

Summary: The long-standing practice of polypharmacy in treating epilepsy is giving way to use of monotherapy. Monotherapy can improve seizure control as well as reduce the risk of serious idiosyncratic reactions, dose-related side effects, and complex drug interactions. Monotherapy also offers improved compliance and cost-effectiveness. The basis of monotherapy is accurate diagnosis and assessment of the patient's seizure type(s), followed by selection of a single appropriate anticonvulsant drug. Many patients currently treated with multiple anticonvulsants can be successfully converted to monotherapy with a carefully monitored program in which troublesome and redundant drugs are gradually withdrawn from the therapeutic regimen.