周围神经病 Peripheral Neuropathy

Department of Neurology, The 2nd affiliated hospital, Harbin Medical University

Peripheral Neuropathy

Outline Guillain-Barre Syndrome Idiopathic facial palsy rigeminal neuralgia

OUTLINE

Anatomy Pathological Processes Clinical classifation Symptoms Investigation

AnatomyPeripheral nerves are made up of numerous axons bound together by three types of connective tissue—endoneurium, perineurium, epineurium. The vasa located in the epineurium provides the blood supply. (fig.1)Peripheral nerve trunks contain myelinated and unmyelinated fibres Crinial nerve Spinal nerve

Pathological Processes

Wallerian degeneration(fig.2) Axonal degeneration Neuronal degeneration Segmental demyelination(fig.3)

Symptoms

Sensory disturbance Motor deficits Tendon reflexes Autonomic disturbances Others

Investigation

Nerve conduction velocity(NCV) Electromyography(EMG) Nerve biopsy Blood tests CSF examination

Trigeminal Neuralgia三叉神经痛

Etiology and Pathology

A facial pain syndrome of unknown cause. Demyelination(fig.4)

Clinical Features It develops in middle to late life. It consists of severe paroxysms electric-

shock-like pain, usually in the V3 and V2 division of the trigeminal nerve (fig.5), lasting for several seconds or minutes each time.

Involvement of V1 division or bilateral disease occurs in less than 5% of cases.

Clinical Features Occurrence during sleep is rare. Painfree intervals may last for minutes to wee

ks, but long-term spontaneous remission is rare.

Sensory stimulation of trigger zones about the cheek, nose, or mouth by touch, cold, wind, talking, or chewing can precipitate the pain.

Clinical Features

Tic douloureux( 痛性抽搐 ) Course could be periodic Physical examination is normal

Diagnosis and Differential Diagnosis

Diagnosis depending on the clinical features Differential Diagnosis

Secondary trigeminal neuralgia Tooth ache Glosspharyngeal neuralgia( 舌 咽 神 经

痛 )

Treatment Drug is preferential AEDs: carbamazapine 0.1 bid po

phenitoin, clonazepam Baclofen( 氯苯氨丁酸 ) VitaminB12 封闭疗法 : 无水酒精 , 甘油 经皮半月神经节射频电凝疗法 手术治疗

特发性面神经麻痹Idiopathic Facial Palsy

(Bell’s palsy)

Idiopathic Facial Palsy(Bell’s palsy)

Anatomy(fig.6) Etiology and pathogenesis Clinical features Diagnosis and differential diagnosis Treatment

Etiology and Pathology

尚未完全阐明，可有一些激发因素 受冷、病毒感染和自主神经不稳神经

营养血管收缩而毛细血管扩张组织水肿压迫面神经面神经水肿和脱髓鞘，严重者有轴突变性。

Clinical features

Onset

□ Occurs in any age, usually unilateral.

□ Paralysis: Progresses over 3 to 72 hours

□ Pain (50%): Near mastoid process

□ Excess tearing (33%)

□ Other: Hyperacusis; Dysgeusia

Clinical features Signs

□ Facial weakness(fig.7)

Upper & Lower

Unilateral

Degree: Partial (30%); Complete (70%)

□ Stapedius dysfunction (33%): Hyperacusis

□ Lacrimation: mildly affected in some patients

□ Taste: No clinically significant changes in most

patients.

□ There should be no sensory loss in the face.

□ Hunt syndrome.

□ No abnormalities beyond the territory of the

facial nerve.

Clinical features Prognosis better

□ Incomplete paralysis

□ Early improvement

□ Slow progression

□ Younger age

Clinical features

Prognosis better

□ Normal taste

□ Electrodiagnostic tests normal

病后 10 天面神经出现失神经，恢复时间延长 ,平均需要 3 个月。一般 1 ～ 2 月内可逐渐痊愈。

Diagnosis and diffential diagnosis

诊断：根据急性起病的周围性面瘫即可诊断。

鉴别： 1 格林 - 巴利综合征 2 各种耳源性面神经麻痹 3 颅后窝的肿瘤或脑膜炎引起的周围性

面瘫

Treatment 原则：改善局部血液循环，减轻面神经水肿，

促进功能恢复。 Corticosteroids: prednisone 60mg qd po

dexamethason VitaminB1,B12 Baclofen Rehabilitation Physiotherapy

急性炎症性脱髓鞘性多发性神经病(acute inflammatory demyelinating p

olyneuropathies, AIDP)

概念急性炎症性脱髓鞘性多发性神经病 (acute infla-

mmatory demyelinating polyneuropathies, AIDP)

又称格林-巴利综合症 (Guillain-Barré Syndrome

GBS), 是以周围神经和神经根的脱髓鞘及小血管周围淋巴细胞及巨噬细胞的炎性反应为病理特点的自身免疫病。

Epidemiology

Incidence: 0.6 to 1.9/100,000/year Male: Female = 1.25: 1 Peak ages: 16~25 years old

45~60 years old

Certain forms of GBS appear to occur more

frequently in certain areas of China.

Etiology and pathogenesis

The precise cause is unclear. GBS often follows minor infective illness,

inoculations or surgical procedures.

Clinical and epidemiologic evidence suggest an association with preceding Campylobacter Jejuni(CJ) infection.(fig.8)

The pathogenesis resembles EAN

Molecular mimicry

Clinical features

GBS Prodrome

It often follows 1-4 weeks after a respiratory infection or diarrhea.

Campylobacter jejuni(CJ) has been particularly implicated as a cause of the diarrhea.

Clinical features

Weakness: Most often symptomatic in legs

Distribution: Proximal + Distal; Symmetric

Severity: Quadriplegia in 30%;

Bedbound another 30%

Respiratory failure.

Clinical features Sensory: ususlly less marked than motor symptoms.

Paraesthesias: Initial symptom in 50%;

Eventually occur in 70% to 90%

Pain

Loss: with classic glove-and-stocking pattern

of sensory loss, but rarely occurs.

Clinical features

Cranial nerve: Ⅶ, ,ⅨⅩ facial weakness is present in 50% of cases. Autonomic dysfunction

tachycardia, cardiac irregularitis, labile blood presure, disturbed sweating and so on.

Monophase course

Clinical features

Clinical classification AIDP AMAN AMSAN Fisher syndrome Unclassifiable GBS

Investigations CSF: a characteristic abnormality, with increased

protein concentration but a normal cell count. Eletrophysiologic studies

marked slowing of motor and sensory condu-

ction velocity,

evidence of denervation and axonal loss.

F wave reflex is delayed or absent. Sural nerve biopsy: demyelination

Diagnostic criteria for GBS(1)

Required for diagnosis

Progressive weakness of more than one

limb.

Distal areflexia with proximal areflexia

or hyporeflexia.

Diagnostic criteria for GBS(2) Supportive of diagnosis Progression for up to 4 weaks. Relatively symmetric deficits. Mild sensory involvement. Cranial nerve(especially )involvement.Ⅶ Recovery beginning within 4 weeks after progression stops. Autonomic dysfunction. No fever at onset. Increased CSF protein after 1 week. CSF white blood cell count10/l. Nerve conduction slowing or block by several weeks.

Differential diagnosis

Hypokalemic periodic paralysis (Hopp) Poliomyelitis Myasthenia gravis(MG)

Treatment Assisting respiration: Patients who are seve -

rely affected are best managed in ICU where facilities are available for monitoring and assis- ted respiration if necessary. Sometimes antibiotic is necessary for preventing respiratory tract’s infection.

肺活量 <20~25ml/kg, 动脉氧分压 <70mmHg

Symptomatic therapy: The aim is to prevent such complications as respiratory failure or vascular collapse.

Treatment Preventing complications: 坠积性肺炎 褥疮 下肢深部静脉血栓、肺栓塞 肢体挛缩、畸形 吞咽麻痹 尿潴留 疼痛 焦虑及抑郁

Treatment

Etiological therapy: Plasma exchange(plasmapheresis) Intravenous immunoglobulin: 0.4g /kg /d for 5 days Corticosteroids: it has not been successful in acute GBS and can bring about adverse outcome. Rehabilitation

Prognosis

The disorder is self-limiting,and improvement occurs over the weeks or months following onset. About 70-75% of patients recover completely, 25% are left with mild neurologic deficits, and 5% die, usually as a result of respiratory failure.

The prognosis is poorer when there is evidence of preceding CJ infection.

慢性炎症性脱髓鞘性多发性神经病 （ CIDP ）

CIDP 主要特点： 慢性进行性或慢性复发性病程。 起病隐袭，少有前驱感染。 进展期平均 3 月，可有复发 - 缓解。 对称肢体远端、近端无力，躯干肌、呼 吸肌、颅神经受累少见。 运动、感觉障碍同存。

CIDP 主要特点：

CSF 可见蛋白 - 细胞分离。 NCV 、 F 波潜伏期均较 AIDP 重。 腓肠神经活检：炎症性节段性脱髓鞘与再 生共存，“洋葱皮样”改变 (fig.9) 。 MRI ：神经增粗。 激素疗效肯定： prednison 100mg qd

po(2-4W) 。