Somatosensory evoked potentials for the electrodiagnosis of meralgia paresthetica

The aim of this study was to evaluate the diagnostic utility of somatosensory evoked potential (SSEP) studies of the lateral femoral cutaneous nerve (LFCN) in assessing patients with meralgia paresthetica. Twenty-one consecutive patients with unilateral meralgia paresthetica, as defined clinically (sensory impairment of lateral aspect of the thigh) and electrodiagnostically (abnormal sensory nerve conduction), and 21 control subjects were studied with two SSEP methods. SSEPs were elicited by stimulation of the LFCN below the anterior superior iliac spine (ASIS stimulation) and by cutaneous stimulation of the lateral aspect of the distal third of the thigh (thigh stimulation). Abnormalities were defined by the SSEP interside latency difference, interside amplitude ratio, or an absent response. The SSEP with ASIS stimulation had a sensitivity of 5% and a specificity of 95%, whereas with thigh stimulation it had a sensitivity of 52% and a specificity of 76%. Overall, SSEP after ASIS stimulation had no diagnostic value. Recording of the SSEP after thigh stimulation is recommended in obese patients only when sensory nerve conduction cannot be determined.     

A case report of an uncommon neuropathy: posterior femoral cutaneous neuropathy

Isolated posterior femoral cutaneous neuropathy is rarely encountered. Electrophysiological documentation has only been made in a few cases. We present a 73 year-old male patient who underwent a coronary angiography procedure which was performed on his right femoral artery 2 months prior of referring to our electromyography (EMG) laboratory. After this event, he had an operation in order to evacuate the hematoma formed in the right inguinal region during the procedure. In the postoperative state he began to complain of a pain and numbness in his right posterior thigh; which had radiated towards his right hip and popliteal fossa. In addition to routine electrophysiological nerve conduction studies conducted in lower extremities; we performed posteriorfemoral cutaneous nerve conduction using the method described by Dumitru and Nelson. While normal response can be obtained easily on the left side; no potential could be obtained from the right.     

Renal Subcapsular Hematoma after Percutaneous Transfemoral Angiography

Vascular complications after percutaneous angiography include hematoma, pseudoaneurysm, arteriovenous fistula, thromboembolism, arterial laceration and infection. Hematomas may occur in the groin, thigh, retroperitoneal, intraperitoneal, or abdominal wall. A 54-year-old female underwent percutaneous transfemoral angiography for the evaluation of cerebral aneurysm. Renal subcapsular hematoma developed 3 hours after the procedure. Renal subcapsular hematoma after percutaneous angiography is very rare. We investigated the possible causes of renal subcapsular hematoma. To avoid this rare complication, we need to perform guide-wire passage carefully from the beginning of the procedure under full visual monitoring.     

Meralgia paresthetica caused by hip-huggers in a patient with aberrant course of the lateral femoral cutaneous nerve

"Hip-huggers" may be a precipitating factor for meralgia paresthetica (MP), especially in thin persons with an aberrant pathway of the lateral femoral cutaneous nerve (LFCN). We describe a 25-year-old woman with a long-standing history of MP caused by an abnormal course of the LFCN and tight trousers, specifically hip-huggers. Ultrasonography was useful for detecting the lesion site and the abnormal pathway of the LFCN. After neurectomy of the LFCN, most of the symptoms of MP were relieved, but mild hypesthesia remained in the lateral thigh.     

Distal lesion of the lateral femoral cutaneous nerve

We report three patients with a typical clinical picture of unilateral meralgia paresthetica in whom routine nerve conduction studies were normal. However, cortical somatosensory evoked potentials were absent after lateral femoral cutaneous nerve (LFCN) stimulation on the affected side. After stimulation of the LFCN in the anterosuperior iliac spine (ASIS) region and recording the responses distal to conventional sites (20 cm from the ASIS), sensory nerve action potentials (SNAPs) were absent in the symptomatic leg, but present in the normal leg. We suggest that thigh paresthesias may be caused by a distal LFCN lesion. Eliciting this requires recording SNAPs distal to conventional sites.     

Direct percutaneous carotid artery stenting with distal protection: technical case report

We describe the technique of percutaneous carotid artery stent placement with distal protection in a patient in whom marked innominate artery ectasia prevented transfemoral access to the right common carotid artery. After induction of general anesthesia, ultrasound was used to guide direct puncture of the common carotid artery followed by the introduction of a 5 French sheath. A GuardWire distal protection balloon (Medtronic, Santa Rosa, CA) was placed distal to the lesion and deployed at nominal diameter. A balloon-expandable stent was deployed without difficulty. Following stent placement, angiography demonstrated improved flow in the entire right carotid artery territory. There were no complications related to cervical soft tissue damage or clinical embolism. The patient tolerated the procedure well and was discharged in 24 hours. Direct carotid access is acceptable in select patients in whom a transfemoral, brachial, or transradial approach is technically difficult. The use of distal cerebral protection devices may reduce cerebral embolism associated with these procedures.     

Meralgia paresthetica: clinical and electrophysiological diagnosis in 120 cases

We report the results of clinical and electrophysiological examinations in 131 cases of meralgia paresthetica (MP) among 120 unselected patients, 69 men and 51 women, aged 15-81 years. All patients experienced permanent or intermittent pain, and all but one had permanent sensory impairment of the thigh. The lateral aspect of the thigh was solely involved in 88 cases and the anterior aspect was also or exclusively involved in 32 cases. The right thigh was involved 62 times and the left 58 times. Symptom duration varied from 2 weeks to 20 years. The initial diagnosis was meralgia paresthetica in 47 cases (39%), root disease in 35 cases, and osteoarthritis in 6 cases; no diagnosis was proposed in the 32 remaining cases. Two cases had undergone previous spine surgery for disk herniation, with no benefit. A precise cause could explain the lateral femoral cutaneous nerve (LFCN) lesion in 46 cases, the other 74 cases being considered idiopathic (25% of patients were obese). Only one case required surgery to relieve symptoms. LFCN conduction was studied orthodromically, distally from the anterior superior iliac spine. The side-to-side amplitude ratio (ssRatio) was greater than 2.3 in 118 of 120 patients (98.3%) and was a better index to confirm a lesion of the LFCN than SNAP amplitude, which was abnormal (less than 3 microV) in 88 cases (73.3%). Only two of the 11 bilateral cases had an ssRatio lower than 2.3 (they were both 2.0). An ssRatio of 2.3 or more and a SNAP amplitude lower than 3 microV provided a specificity of 98.75% or more. The mean axonal loss was 88%. These clinical and electrophysiological data highlight the central role the neurophysiologist should play in diagnosing MP by means of an LFCN conduction study.     

显微血管减压术后颅内出血的原因及应对策略

目的 探讨显微血管减压(MVD)术后颅内出血的原因及应对策略.方法 对12例面肌痉挛、三叉神经痛MVD术后颅内出血患者的临床资料进行回顾性分析,并对相关文献进行复习.结果 本组患者中,小脑半球实质内血肿者3例,小脑出血破入脑室3例,蛛网膜下腔出血2例,脑室出血2例,后颅窝硬膜外血肿1例,幕上硬膜下血肿1例.1例脑室出血...     

不同方法对股动脉穿刺点局部压迫止血效果的评价

目的 比较优力舒、沙袋压迫及绷带加压包扎对股动脉穿刺点的止血效果,为股动脉穿刺点止血选择最好的局部压迫方法。方法 将207例行股动脉穿刺术患者分为3组:优力舒组(105例)、沙袋组(62例)及绷带组(40例)。三种不同方法对血管内治疗后股动脉穿刺点进行局部压迫,分别观察止血效果。结果 优力舒组仅1例发生穿刺点渗血;而沙袋组及绷带组分别有4例及7例发生穿刺点渗血。3组穿刺点渗血发生率相比,沙袋组明显低于绷带组(P<0.01),而优力舒组则明显低于另两组(P<0.01),且优力舒粘贴部位皮肤无过敏现象。结论 使用优力舒压迫股动脉穿刺点具有止血效果好,无明显不良反应,且操作简便,病人易于接受。     

Skin biopsy in assessing meralgia paresthetica

Introduction: Meralgia paresthetica is a focal neuropathy caused by compression of the lateral femoral cutaneous nerve (LFCN). The disease can be difficult to assess by neurophysiological or imaging studies. Methods: We studied 5 patients who presented to our neuromuscular clinic from April 2012 to December 2014 with a clinical suspicion of meralgia paresthetica and had skin biopsies with intraepidermal nerve fiber density (IENFD) evaluation. Results: The mean age at onset was 37.2 (range 21–59) years. There were 4 women and 1 man. Two were obese, 2 wore tight jeans, and 1 had mild diabetes mellitus. IENFD was reduced in the symptomatic proximal thigh in all 5 patients and was also reduced in the asymptomatic thigh in 2 patients. It was normal in the distal leg in 4 patients. Conclusion: Meralgia paresthetica is associated with loss of small intraepidermal nerve fibers. Skin biopsy with IENFD evaluation may be a useful diagnostic tool for this disease. Muscle Nerve 53 : 641–643, 2016     

Meralgia paraesthetica as the first symptom of a metastatic tumor in the lumbar spine

Meralgia paraesthetica is clinically characterized by a disturbed sensation at the anterolateral side of the thigh with normal motor function. The syndrome is usually caused by compression of the lateral femoral cutaneous nerve. We now report a patient in whom meralgia paraesthetica was the first manifestation of a metastatic carcinoma in the second lumbar vertebra. Other cases of meralgia paraesthetica probably caused by nerve root compression have been described by others. Therefore we advocate ancillary investigations in this usually harmless clinical syndrome in order to rule out a lesion of the second or third lumbar root.     

Direct percutaneous carotid artery stenting with distal protection: technical case report

Abstract

We describe the technique of percutaneous carotid artery stent placement with distal protection in a patient in whom marked innominate artery ectasia prevented transfemoral access to the right common carotid artery. After induction of general anesthesia, ultrasound was used to guide direct puncture of the common carotid artery followed by the introduction of a 5 French sheath. A GuardWire distal protection balloon (Medtronic, Santa Rosa, CA) was placed distal to the lesion and deployed at nominal diameter. A balloon-expandable stent was deployed without difficulty. Following stent placement, angiography demonstrated improved flow in the entire right carotid artery territory. There were no complications related to cervical soft tissue damage or clinical embolism. The patient tolerated the procedure well and was discharged in 24 hours. Direct carotid access is acceptable in select patients in whom a transfemoral, brachial, or transradial approach is technically difficult. The use of distal cerebral protection devices may reduce cerebral embolism associated with these procedures.     

Pulsed Radiofrequency Neuromodulation Treatment on the Lateral Femoral Cutaneous Nerve for the Treatment of Meralgia Paresthetica

We describe a rare case of pulsed radiofrequency treatment for pain relief associated with meralgia paresthetica. A 58-year-old female presented with pain in the left anterior lateral thigh. An imaging study revealed no acute lesions compared with a previous imaging study, and diagnosis of meralgia paresthetica was made. She received temporary pain relief with lateral femoral cutaneous nerve blocks twice. We performed pulsed radiofrequency treatment, and the pain declined to 25% of the maximal pain intensity. At 4 months after the procedure, the pain intensity did not aggravate without medication. Pulsed radiofrequency neuromodulation treatment on the lateral femoral cutaneous nerve may offer an effective, low risk treatment in patients with meralgia paresthetica who are refractory to conservative medical treatment.     

Brainstem ptosis (midbrain ptosis) associated with mesencephalic hemorrhage

We reported a patient with a brainstem ptosis (midbrain ptosis) associated with mesencephalic hemorrhage. A 57-year-old woman had the sudden onset of bilateral blepharoptosis and diplopia. On admission, computed tomography of the brain and magnetic resonance imaging disclosed a small hematoma in the left tegmentum of midbrain. She had no past history of hypertension of head trauma. Cerebral angiography gave no additional informations. The lesion involving the central caudal subnucleus of IIIrd nerve nucleus may be responsible for the bilateral ptosis, since this finding is consistent with current models of oculomotor organization in monkeys (Warwick 1953).     

Lateral pontine hemorrhage: reappraisal of benign cases

We reviewed 6 computed tomography-documented cases of primary lateral pontine hemorrhage that occurred in our two institutions over a 2-year period. All patients survived the acute stroke, with excellent functional recovery in 4. The level of consciousness of the patient and the size of the hemorrhage had no consistent bearing on outcome. Both of these features have been considered important prognostic indicators in patients with pontine hemorrhage, but in our series benign outcomes were not restricted only to patients who were alert or had small hemorrhages; on the other hand, severe disability was noticed in 1 patient with a small hematoma strategically located in the pontine tegmentum. Our observations suggest that, although some patients with lateral pontine hemorrhage have a good prognosis, there is no single determinant that predicts outcome in a given patient.     

立体定向穿刺加Ommaya囊置入术在颅内囊性病变中的临床应用

目的探讨立体定向穿刺术和Ommaya囊置入术在治疗颅内囊性病变中的应用技巧及疗效。 方法回顾性分析上海华山医院伽马分院2012年11月至2013年4月收治的3例不同颅内囊性病变患者,对该3例诊断明确的颅内囊性患者(分别为右颞转移瘤、左侧CPA神经鞘瘤、颅内多发病变)在立体定向穿刺后置入Ommaya囊,再根据具体病情给予囊腔逐渐抽吸,使囊液逐渐减少至最少,给予伽玛刀的治疗方法。 结果3例病例均在多次抽取囊液后行伽玛刀治疗,无不适反应,均未出现皮肤感染、颅内感染、硬膜外血肿等因手术操作导致的并发症。 结论治疗颅内囊性病变,尤其是高龄病人或由于其他原因不能耐受全麻手术的患者时,立体定向加Ommaya囊置入术不失为一种简便、经济、有效、微创的好方法。     

Anterior Cranial Fossa Dural Arteriovenous Fistulae Presenting as Subdural Hematoma

Anterior cranial fossa dural arteriovenous fistulae (DAVFs) are very rare and the bleeding rate is very high, especially in the presence of leptomeningeal draining vein and aneurysmal varix formation. A 85-year-old male patient presented with subdural hematoma (SDH). Magnetic resonance image (MRI) and transfemoral carotid angiography (TFCA) disclosed DAVF at the anterior cranial fossa with bilateral arterial feeders and leptomeningeal draining vein with varix formation. The lesion was treated by simple ligation of pial connecting vein using low frontal craniotomy. In comparison with DAVFs of the other sites, the anterior cranial fossa DAVF is difficult to manage by endovascular treatment due to not only the difficulty of transvenous access but the risk of visual impairment when using transarterial route. Surgical ligation of pial connecting vein is feasible and effective treatment.     

无框架立体定向下微创穿刺联合尿激酶治疗外伤性脑内血肿

目的探讨在无框架立体定向仪下行微创穿刺联合尿激酶在外伤性颅内血肿中的应用。方法对2012年02月~2013年01月37例外伤性颅内血肿患者的微创治疗疗效进行回顾分析。首先外伤性颅内血肿经CT检查确诊后在24小时内,行无框架立体定向微创穿刺后连接一次性颅内血肿清除套装引流,术后每日两次经套装注入尿激酶并引流积血。结果 37例患者均治愈出院,肢体活动恢复正常29例（73.38%）,轻度残疾6例（16.22%）,2例出现重度对侧肢体偏瘫（5.4%）;13例出现失语症状（35.14%）,余患者恢复良好。住院时间最短7天,最长18天,平均住院时间为10.7天。结论立体定向下微创穿刺定位准、疗效确切、创伤小,术后并发症低,有效地减轻了患者的经济负担。     

Estimulación medular como tratamiento de la meralgia parestésica. ¿Es factible? Reporte de caso

Meralgia paresthetica is a neurological disorder caused by a neuropathy of the lateral femoral cutaneous nerve. Its etiology can be spontaneous or iatrogenic. It is characterized by pain, paresthesia, and numbness in the anterolateral aspect of the thigh. Diagnosis is based on clinical examination, although image and neurophysiological tests can be useful as well. Despite conservative measures use to be effective in most of patients, refractory cases can benefit from alternative treatments. Available surgical procedures are: nerve decompression (neurolysis) or section (neurectomy) and radiofrequency ablation. We present a case of refractory meralgia paresthetica where spinal cord stimulation was used as a possible effective technique in pain relief and to avoid the neurectomy of the lateral femoral cutaneous nerve.     

Quantitative analysis of epidermal innervation in Fabry disease

OBJECTIVE: To use skin biopsy specimens to quantitate the cutaneous innervation density of Fabry patients who had preserved renal function. BACKGROUND: The small fiber neuropathy of Fabry disease is difficult to detect and quantitate by conventional methods. Because this neuropathy is a common characteristic of Fabry disease, quantitating changes in this parameter would be helpful in demonstrating the effectiveness of enzyme or gene replacement therapy. METHODS: Patients underwent skin biopsy at the thigh and foot. Innervation density was determined by counting free nerve endings in the epidermis. These data were compared with nerve conduction studies, and in selected patients, fiber quantitation of sural nerve biopsy specimens. RESULTS: The Fabry patients had normal results of nerve conduction studies and large fiber quantitation by sural nerve biopsy. However, the involvement of small cutaneous fibers in these patients was easily demonstrable and quantifiable by skin biopsy. All patients showed severe loss of intraepidermal innervation at the ankle, but fiber loss at the distal thigh was proportionately less severe. CONCLUSIONS: The nerve damage in Fabry patients with preserved renal function involves exclusively small myelinated and unmyelinated fibers, and skin biopsy is a useful in detecting and quantitating such damage. Comparison of cutaneous innervation density with quantitation of sural nerve biopsy specimens demonstrated that skin biopsy specimens were as sensitive in detecting the presence of neuropathy as were the nerve specimens. It is speculated that analysis of cutaneous innervation may provide a useful marker of the nervous system's response to specific therapy for Fabry disease.