听神经瘤误诊分析

对经耳鼻咽喉科首诊，最终由神经外科手术全切或部分切除的经病理证实的７２例听神经瘤进行早期误诊分析，误诊时间平均５．５年，误诊病种为神经性耳聋、突发性耳聋、神经性耳鸣、颈椎病、鼻咽癌等。文中重点讨论了误诊原因。     

囊性听神经瘤的诊断与治疗

目的 总结囊性听神经瘤的临床特点及治疗效果。方法 22例患者术前均应用CT和MRI进行诊断,应用乙状窦后入路手术切除肿瘤。术中证实,术后病理确诊囊性听神经瘤。结果 22例肿瘤全切除18例,术后面神经功能分级：Ⅱ级4例、Ⅲ级7例、Ⅳ级3例、Ⅴ级2例、Ⅵ级2例;次全切除4例,面神经功能Ⅱ级。结论 由于囊性听神经瘤的临床特点及疗效差,应把它作为一种特殊亚型来处理。     

A rare cause of digital pain: the subepineural Pacinian corpuscle

A new case of subepineural Pacinian corpuscle is described in a 33-year-old woman without a history of trauma. Surgical excision resulted in complete pain relief.     

Mixed solid and cystic acoustic neuroma: MR features and differential diagnosis

We present a very rare case of combined cystic and solid acoustic neuroma investigated by magnetic resonance imaging (MRI). This case illustrates the value of MRI in the characterization of tumors in the posterior cranial fossa, particularly acoustic neuromas, and its diagnostic impact in unusual situations. The differential diagnosis of cystic and mixed lesions in the cerebellopontine angle is discussed. Offprint requests to: B. Duvoisin     

内窥镜辅助下侧颅底手术

目的观察内窥镜辅助下侧颅底手术的疗效及并发症。方法在内窥镜辅助下采用迷路进路及乙状窦后进路行听神经瘤手术11例，颅中窝进路及颅中窝、乳突联合进路行岩尖胆脂瘤手术5例。结果听神经瘤全切除9例，2例残留部分包膜；术中内窥镜下探查面神经均完整，其中9例术后无面瘫表现，2例术后出现轻度周围性面瘫；术中内窥镜下探查蜗神经均完整，2例术后听力与术前比较保持不变，9例出现不同程度听力下降。其中，中度感音神经性耳聋1例，中重度2例，重度3例，极重度3例。岩尖胆脂瘤患者均行病变全切除，3例术前面瘫患者经术中减压，术后9个月内均恢复。2例术后出现中重度传导性耳聋，其余患者术后听力无明显改变。结论侧颅底手术中使用内窥镜可提高血管、神经保全率及病变全切率，但也有其不足，仅能作为显微镜手术的辅助使用。     

Afterdischarge and interactions among fibers in damaged peripheral nerve in the rat

Sensory fibers trapped in nerve-end neuromas become abnormally excitable, and produce an ectopic discharge which is believed to contribute to paresthesias and pain associated with chronic nerve injury in man. Here we report that stimulation of injured nerves can alter this discharge, directly by antidromic invasion of active neuroma fibers, and indirectly through interactions with neighboring fibers. Antidromic stimulation of spontaneously active fibers in experimental neuromas in the rat sciatic nerve, using single electrical stimulus pulses, produced time-locking of rhythmic spontaneous firing and of spontaneous impulse bursts. Some initially silent fibers generated a burst of rhythmic afterdischarge when stimulated in this way. Stimulation delivered in brief trains (tetani) produced more prolonged alterations in spontaneous neuroma discharge, including excitation, suppression and combinations of the two. In some cases initially silent fibers were activated for extended periods. These responses to tetanic stimulation occurred even when the active fibers were not themselves stimulated, and reflect a novel form of fiber-fiber interaction in neuromas that we term 'crossed afterdischarge'. This interaction probably results from the accumulation of potassium ions within the extracellular compartment adjacent to active neuroma fibers during activation of their neighbors. It differs fundamentally from the high safety factor ephaptic cross-talk seen in acutely cut nerves and in neuromas of 30 or more days standing.     

细胞周期蛋白D1在听神经瘤中的表达及临床意义

目的评估听神经瘤中细胞周期蛋白D1(Cyclin D1)的表达及其与组织学特点、临床听力学特征的相关性。方法回顾性分析病理学上确诊听神经瘤的17例患者组织切片,进行组织病理学分型(Antoni分型)和免疫组织化学染色分析Cyclin D1的表达,结合临床一般资料与听力学检测数据并分析其相关性。结果 17例患者组织切片中有9例(53%)Cyclin D1阳性表达,与Cyclin D1表达阴性的患者相比,语频平均听阈(PTA)的平均值较低(P<0.05),Cyclin D1表达阳性的患者在2 000 Hz频率平均听阈较低(P<0.05)。没有发现Cyc-lin D1的表达与性别、侧别和病理分型相关(P>0.05)。结论 Cyclin D1可能在听神经瘤的细胞增殖与分化调节过程中发挥重要的作用,进一步观察Cyclin D1在听神经瘤细胞增殖与分化调节过程中的作用,对探讨听神经瘤的发生发展有着重要的意义。     

MRI平扫加增强检查对微型、小型听神经瘤的诊断价值

目的评价增强MRI对微型、小型听神经瘤的诊断价值。材料和方法本文收集了经手术和病理证实的微型听神经瘤13例（d≤10mm）,小型听神经瘤19例（10〈d≤20mm）,男15例,女17例,年龄33—61岁,平均41．8岁,采用SignaHDX3．OTMRI超导型MR系统平扫及增强扫描,对其影像学表现进行回顾性分析,对肿瘤病灶边缘、信号、邻近结构关系进行比较。结果32例微、小型听神经瘤Gd—DTPA扫描呈明显强化,病灶的位置．边缘及邻近结构关系更明确。肿瘤Tl加权序列为等或稍低信号,T2加权序列为高信号或稍高混杂信号,内听道均未见扩大。11例病灶局限在到内听道内,肿瘤直径约0．3—1．2mm,平均0．54mm;3例肿瘤位于听神经,T1WI,T2WI听神经稍增粗、未见异常信号,增强扫描后呈点片状强化,18例肿瘤大部分位于内听道内,其肿瘤少部分突入桥小脑角肿瘤直径约0．8—2．0mm,平均1．24mm。结论MRI平扫＋增强是防止微型、小型听神经瘤漏诊最有效方法,其诊断准确、可靠。     

The tibial neuroma transposition (TNT) model of neuroma pain and hyperalgesia

Peripheral nerve injury may lead to the formation of a painful neuroma. In patients, palpating the tissue overlying a neuroma evokes paraesthesias/dysaesthesias in the distribution of the injured nerve. Previous animal models of neuropathic pain have focused on the mechanical hyperalgesia and allodynia that develops at a location distant from the site of injury and not on the pain from direct stimulation of the neuroma. We describe a new animal model of neuroma pain in which the neuroma was located in a position that is accessible to mechanical testing and outside of the innervation territory of the injured nerve. This allowed testing of pain in response to mechanical stimulation of the neuroma (which we call neuroma tenderness) independent of pain due to mechanical hyperalgesia. In the tibial neuroma transposition (TNT) model, the posterior tibial nerve was ligated and transected in the foot just proximal to the plantar bifurcation. Using a subcutaneous tunnel, the end of the ligated nerve was positioned just superior to the lateral malleolus. Mechanical stimulation of the neuroma produced a profound withdrawal behavior that could be distinguished from the hyperalgesia that developed on the hind paw. The neuroma tenderness (but not the hyperalgesia) was reversed by local lidocaine injection and by proximal transection of the tibial nerve. Afferents originating from the neuroma exhibited spontaneous activity and responses to mechanical stimulation of the neuroma. The TNT model provides a useful tool to investigate the differential mechanisms underlying the neuroma tenderness and mechanical hyperalgesia associated with neuropathic pain.     

Role of Nd:YAG laser for prevention of neuroma formation: an in vivo experimental study

Nerve transection is commonly followed by the development of neuroma at the proximal stump. It can be very painful especially at exposed sites. It may arise spontaneously or after mechanical irritation. Neuroma and its high recurrence rate might be resisting problems to treat. Various treatment modalities for neuroma and its recurrence have been proposed, but none has provided satisfactory results. The present study was conducted to evaluate the neodymium:yttrium aluminum garnet (Nd:YAG) laser (1,064 nm) nerve transection technique for prevention of neuroma formation. There were 48 facial nerves out of 24 Rex rabbits divided into two equal groups. The 24 left-sided facial nerves at group A were subjected to Nd:YAG laser for nerve transection, while the 24 right-sided facial nerves at group B were subjected to scalpel nerve transection. The results were grossly and histopathologically evaluated. Grossly, laser-transected nerves showed an infrequent incidence of neuroma formation. Histopathologically, laser-transected nerves showed photothermal degenerative changes of the axons and myelin sheaths with intact perineurium and endoneurium. No Schwann cell hyperactivity could also be elicited among laser-transected nerves. Nd:YAG laser was found to be an effective tool that could be applied, whenever it is possible, for division of major nerves to prevent the formation of the subsequent stump neuroma. Moreover, this technique should be considered during treatment of well-established neuroma to prevent the challenging reported high incidence of recurrence.