Peripheral nerve injection injury with antiemetic agents

Antiemetics are widely used drugs, frequently administered to alleviate postoperative and postchemotherapeutic nausea and vomiting. While antiemetics do not induce peripheral neurotoxicity when administered systemically, it is not known whether peripheral nerve injury can occur as a result of inadvertent intraneural injection during intramuscular administration. The purpose of this study was to characterize the neurotoxic effect of three commonly used antiemetic agents (promethazine, dimenhydrinate, and prochlorperazine) as compared to saline in the rat sciatic nerve model. Intrafascicular and extrafascicular injection as well as direct application of the antiemetic drugs were performed. Nerves were harvested at 2 weeks postoperatively for histology and morphometry, with an additional sacrifice point at 8 weeks for the intrafascicular injection group. Injection injuries caused by antiemetic drugs differed depending on the agent injected and the location of injection. Extrafascicular injection and direct application caused no damage. Intrafascicular injection caused diffuse axonal injury in the promethazine and dimenhydrinate groups, while prochlorperazine caused only focal injury. Regeneration was prominent at 8 weeks in all intrafascicular injection groups in this rat model. Prochlorperazine thus appears to be less neurotoxic when injected intraneurally and should preferentially be used for intramuscular injections.     

Traction on the orthopedic table and pudendal nerve injury. Importance of electrophysiologic examination

PURPOSE OF THE STUDY: We performed a retrospective study about perioperative pudendal nerve palsy following fracture table tractions. MATERIAL: Six palsies were investigated. Mean age was 26 years. All of them presented sensitive and motor dysfunctions secondary to nerve compression following tractions on the fracture table. METHODS: All of them had complete electrophysiological recordings including perineal electromyogram, measurement of sacral roots latencies, sensory velocity of the dorsal nerve of the penis, somatosensory evoked potentials of the pudendal nerve and measurement of its terminal branches. RESULTS: Neurological symptoms were stereotyped associating sensory signs and sexual disorders, must of them being transient. Perineal electrophysiological examination always confirmed reality of pudendal nerve palsy. DISCUSSION: We discuss incidence, mechanism, etiology and prevention of this pudendal nerve palsy. CONCLUSION: Emergence of stereotyped perineal symptoms following orthopaedic surgery, especially after tractions on fracture table, must prevail on physicians to search for pudendal nerve palsy. Usual outcome is good in the six months following surgery, but definitive aftermath does occur. Perineal electrophysiological examination can confirm pudendal nerve palsy and give prognosis elements.     

Peripheral nerve hemangioblastoma

Capillary hemangioblastoma (HB) is a benign, highly vascular tumor limited almost exclusively to the central nervous system (CNS). It occurs primarily in the posterior fossa and less often in the spinal cord. We report three cases of HB occurring in peripheral nerve, two intradural tumors arising in a C4 and a cauda equina nerve root, respectively, and a third lesion in the sciatic nerve at mid thigh. The patients, 1 woman and 2 men, ranged in age from 25 to 49 years. Two had von Hippel-Lindau disease, an association usually found in one-third of CNS HBs, and one had a family history of pheochromocytoma. In every way, HBs of peripheral nerve were indistinguishable from their CNS counterpart. Ranging in size from 1.5 to 5.5 cm in diameter, the tumors were well circumscribed and contained a myriad of small caliber vessels lined by endothelial cells and surrounded by pericytes. Throughout, the lesions were rich in large, often vacuolated stromal cells. In all of the cases, these stained strongly for vimentin and neuron-specific enolase; only one showed focal S100 protein reactivity. Surgical therapy required excision of the affected nerve roots in the first two cases. In the third case, prominent extension of the tumor within epineurium permitted a microsurgical resection with sparing of sciatic nerve fascicles. No tumor recurred during a follow-up period of 5 to 20 months.     

Peripheral nerve conduction following recovery from Guillain-Barre syndrome

The material comprises 10 cases with a history of Guillain-Barré syndrome within the last several years in which clinical investigations failed to demonstrate any abnormalities. Electrophysiological investigations of peripheral nerves including conduction velocity in motor fibres--maximal and minimal, sensory fibres, standardized terminal latency--showed presence of changes evidencing slight but persisting subclinical lesion to peripheral nerves, especially in subjects affected in early childhood. Slowing of conduction involved motor as well as sensory fibres in these nerves and was more pronounced in the ulnar nerve than in the remaining nerves (peroneal, axillary, musculocutaneous and facial).     

Neuroma of the sural nerve as a complication of stripping of the small saphenous vein

From 1989 to 1996, 61 patients, including 66 knees, aged 8 to 62, were diagnosed as mediopatellar plica syndrome of knee after arthroscopic examination. Twenty-one cases were misdiagnosed as medial meniscal lesions before arthroscopic examination. Fifty-nine patients (64 knees) underwent arthroscopic resection of the plicae and 2 patients underwent opened resection. Fifty-nine cases had an average follow-up of seven months. Fifty cases (54 knees) of them showed excellent and good results.     

Adaptive functioning following traumatic brain injury and orthopedic injury: a controlled study

BACKGROUND: In an effort to intensify osteosarcoma therapy, systemic ifosfamide was added pre- and postoperatively to an already aggressive three-drug regimen. In a subgroup of patients, loco-regional treatment intensification was attempted by using the intraarterial route to give cisplatin. PATIENTS AND METHODS: Patients < or = 40 years at diagnosis of a localised, de novo high-grade central extremity osteosarcoma were eligible for inclusion into study COSS-86 if registered within three weeks from biopsy. Doxorubicin, high-dose methotrexate, and cisplatin were given to all patients. Patients who fulfilled one or more of three defined high-risk criteria received early systemic treatment intensification by adding ifosfamide as the fourth agent. Preoperatively, these high-risk patients received cisplatin either intraarterially or intravenously. RESULTS: 171 eligible patients were entered, of which 128 were stratified into the high-risk group. When all 171 were analysed by intention-to-treat, actuarial overall and event-free survival rates at ten years were 72% and 66%, respectively. No benefit of intraarterial cisplatin application was detected. Cumulative treatment toxicity was considerable. CONCLUSIONS: In a multicenter setting, intensive treatment of osteosarcoma according to protocol COSS-86 led to long-term disease-free survival for two thirds of patients. We saw no benefit of using the intraarterial route to administer cisplatin.     

Peripheral nerve revascularization: a current literature review

Gene therapy of human cancer is likely to be most effective when it is directed at targets that are expressed in cancer cells but are lacking from other cells. Human papillomaviruses can provide such targets, since these viruses are present in many cervical and oral cancers, and are likely to be etiological agents of the tumor. Continued expression of human papillomavirus genes is probably necessary for the growth of these cancers, and effective gene therapy could consist of antisense or ribozyme molecules directed against these genes. Some human papillomavirus gene products are antigenic, and immunotherapy based upon these antigens might prove clinically beneficial. Human papillomaviruses have specific promoters, are linked to toxin genes, the toxin may be selectively expressed by tumor cells where the virus genes are active. Thus, there are several approaches for the development of specific gene therapy for human cancers that contain human papillomaviruses.     

Recurrent laryngeal nerve paralysis: a complication of thyroidectomy

OBJECTIVE: To study factors related to recurrent laryngeal nerve (RLN) paralysis, a major complication of thyroidectomy. DESIGN: Retrospective study of outcome of patients' medical records. PATIENTS AND METHODS: Records of 361 patients who underwent thyroidectomy by otolaryngologists at Ramathibodi Hospital were reviewed for RLN paralysis. Main Outcome Measures: RLN injury was analyzed in relation to types of surgery, RLN identification, and histopathology. The analysis was based on the number of RLNs at risk. RESULTS: The incidence of permanent RLN paralysis was 2.38%. Both the permanent RLN paralysis and temporary RLN paralysis were significantly related to the histopathologic findings of malignancy (p < .005). The positive identification of RLN and the types of surgery were not found to be significant factors in either permanent RLN paralysis or temporary RLN paralysis. CONCLUSIONS: There was insufficient evidence to support that the identification of RLNs during surgery would be a significant factor in reducing the likelihood of RLN paralysis. However, RLNs should be identified to avoid iatrogenic injury and subsequent paralysis. Meticulous surgical technique should be applied in patients whose results of fine-needle aspiration biopsy suggested malignancy, as there is the possibility of difficult surgery and potential iatrogenic RLN paralysis in this group of thyroid patients.     

Aspiration: a potential complication to vagus nerve stimulation

PURPOSE: Vagus nerve stimulation (VNS) is reported to reduce the frequency of seizures in children and adults without causing serious side effects. However, clinical observation of swallowing difficulties in 2 children treated with VNS made further investigation necessary. METHODS: Seven patients aged 4-18 years and treated with VNS for 6-14 months were investigated with videoradiography during barium swallow. The children performed 5-30 barium swallow investigations with the VNS device turned off, running as programmed, or set at continuous stimulations. The degree of aspiration was scored from 0 to 3. RESULTS: In 5 of 7 children, of whom reported transient swallowing difficulties, no change in the degree of aspiration was noted. The 2 children with swallowing difficulties, however. showed increased aspiration score when the stimulator was set at continuous stimulations. In 1 the score also appeared to increase with the VNS running as programmed (p > 0.05). Both children had severe mental and motor disabilities. CONCLUSIONS: Before and during VNS treatment patients should be evaluated with regard to swallowing problems. There needs to be an easy way to turn the device on and off to avoid aspirations, a hazardous and potentially life-threatening complication of VNS.     

Occipital nerve neuralgia as postoperative complication. Views on etiology and treatment

INTRODUCTION: Meta-iodobenzylguanidine (MIBG) in its 131I-labeled form is clinically used as a tumor-targeted radiopharmaceutical in the diagnosis and treatment of adrenergic tumors. This well established drug may have additional clinical applications as a radiosensitizer or hyperthermic agent, ie., MIBG reportedly inhibits mitochondrial respiration in vitro. The mechanism for MIBG inhibition of cellular oxygen consumption is uncertain. Moreover, MIBG reportedly stimulates glycolysis both in vitro and in vivo. Our studies show the effect of MIBG on 9L glioma oxygen consumption and redox status with tumors cells in vitro and in vivo. MATERIALS AND METHODS: The effects on electron transfer were determined by following oxygen consumption with a Clark oxygen electrode. Fluorescence measurements were used to determine effects of MIBG on intracellular electron acceptors, NADPH and flavoproteins, in vitro and in vivo. 31P-NMR was used to determine alterations in tumor cell pH in vivo. RESULTS: Our results show the inhibition of oxygen utilization with MIBG for cell suspensions in vitro. The same results were demonstrated for tumor cell suspensions rapidly isolated from tumors grown in rats. Moreover, NAD(P)H and flavoprotein (Fp) fluorescence changes were observed to rapidly occur following MIBG addition in vitro. Changes in intracellular pH measured with 31P-NMR, in vivo, precede the changes in fluorescence of NAD(P)H and Fp obtained with frozen sections of tumor. CONCLUSIONS: We conclude that 31P-NMR measurements and fluorescence changes, following MIBG injection, can be used as criterion for selecting the proper time to treat tumors with ionizing radiation or hyperthermia.     

Peripheral nerve stimulation in a whole-body echo-planar imaging system

Echo-planar techniques in MRI use a rapidly oscillating frequency-encoding gradient with the potential to produce peripheral nerve stimulation. To evaluate the incidence, type, and location of stimulation in a commercial whole-body scanner, we studied two groups: (a) 173 consecutive individuals scanned by echo-planar imaging for other purposes and (b) seven subjects who were scanned with an extensive set of 36 echo-planar sequences (with prompting after each scan to report any peripheral nerve stimulation) to test the effects of various parameters. Although only 5% of group A reported symptoms of peripheral nerve stimulation, all in group B experienced some type of stimulation, dependent primarily on direction of the oscillating gradient and location of the body within the gradient coil. Maximum stimulation typically occurred 30 to 40 cm from isocenter in the region of maximum dB/dt. Generally, y gradients produced truncal stimulation, and x gradients produced stimulation in the head. When hands were clasped over the abdomen, a tingling in the hands occasionally was felt. Patients should be instructed to keep their hands apart.     

Chylothorax as a complication of sarcoidosis

This case report features a male patient of 45 years of age presenting with a right sided moderately compressive pleural effusion, that was clearly identified as chylothorax on thoracocentesis. Sarcoidosis with systemic involvement had already been diagnosed in 1995 by a parotid gland biopsy. Thoracoscopy revealed multiple discrete nodules parietally besides a number of more extensive yellowish lesions resembling malignant lymphoma. However visualization of a thoracic duct leakage was not possible. Histologically the biopsies taken represented exclusively non-caseating sarcoidosistype granulomas. Complete and permanent remission of the chylothorax was achieved within only ten days following talcum pleurodesis, alimentary measures and induction of systemic steroid therapy. The etiological classification of this extremely rare complication appears very clear. Pathogenetic and differential therapeutic aspects are discussed against the background of a review of the literature.     

Epididymo-orchitis as a complication of brucellosis

A study of 84 patients who were diagnosed with epididymo-orchitis between July 1987 and September 1993 is presented. Brucellosis was a complication in 14 cases (17%). All 14 cases had elevated agglutination titers. Brucella blood culture was found to be positive in 4 of 14 cases (28.5%). Standard therapy regime (streptomycin plus tetracycline) was effective in 13 of 14 (93%) cases.     

Temporary paresis of the phrenic nerve as a complication of subclavian vein puncture (author's transl)

A case of phrenic nerve paresis as a complication of puncture of the right subclavian vein in local anesthesia is reported. The paresis and phrenoparalysis disappeared after 90 minutes. Possible reasons are discussed.     

Evaluation of nerve recovery from minimal-duration crush injury

The recovery of damaged peripheral nerves has been the subject of multiple studies. The effects of an inadvertent clamping of a nerve has not been well examined. An experiment was performed to evaluate the effects of a minimal-duration crush injury on the rat sciatic nerve and to determine if walking track analysis was useful in evaluating the short-term functional deficit. Ten Sprague-Dawley rats underwent high-pressure, short-duration crush injuries. Walking track analysis was done regularly for 3 weeks. Histological specimens for light and electron microscopy were taken at postoperative days 3, 7, 14, 21, and 42 from similar animals. There was significant decrease in function by the second week, which then improved to control levels after week 3. Toluidine blue and electron microscopic findings confirmed the clinical course, while routine histological findings tended to lag behind the return of function. Walking track analysis appears to be an effective method of evaluating the short-duration nerve crush injury.     

Pseudoaneurysm as a complication of knee arthroscopy

This is a report of a pseudoaneurysm of the inferior medial geniculate artery following knee arthroscopy. This case was treated successfully with embolization.