1/21. Interfacing the body's own sensing receptors into neural prosthesis devices.Functional electric stimulation (FES) is today available as a tool in muscle activation used in picking up objects, in standing and walking, in controlling bladder emptying, and for breathing. Despite substantial progress over nearly three decades of development, many challenges remain to provide a more efficient functionality of FES systems. The most important of these is an improved control of the activated muscles. Instead of artificial sensors for feedback, new developments in electrodes to do long-term and reliable recordings from peripheral nerves emphasize the use of the body's own sensors. These are already installed and optimised through millions of years of natural evolution. This paper presents recent results on a system using electrical stimulation of motor nerves to produce movement and using the natural sensors as feedback signals to control the stimulation that can replicate some of the functions of the spinal cord and its communication with the brain. We have used the nerve signal recorded from cutaneous nerves in two different human applications: (1) to replace the external heel switch of a system for correction of spastic drop foot by peroneal stimulation, and (2) to provide an FES system for restoration of hand grasp with sensory feedback from the fingertip. For the bladder function, the sacral root stimulator is a useful control tool in emptying the bladder. To decide when to stimulate, we are at present carrying out experiments on pigs and cats using cuff electrodes on the pelvic nerve and sacral roots to record the neural information from bladder afferents. This information can potentially be used to inhibit unwanted bladder contractions and to trigger the FES system and thereby bladder emptying. Future research will show whether cuffs and other types of electrodes can be used to reliably extract signals from the large number of other receptors in the body to improve and expand on the use of natural sensors in clinical FES systems.- - - - - - - - - - ranking = 1keywords = nerve (Clic here for more details about this article) |
2/21. Self-controlled dorsal penile nerve stimulation to inhibit bladder hyperreflexia in incomplete spinal cord injury: a case report.Intermittent catheterization is not always successful in achieving continence in spinal cord injury (SCI) and often requires adjunctive methods. electric stimulation of sacral afferent nerves reduces hyperactivity of the bladder. This report describes application of self-controlled dorsal penile nerve stimulation for bladder hyperreflexia in incomplete SCI. The patient was a 33-year-old man with C6 incomplete quadriplegia who managed his bladder with intermittent self-catheterization and medication. Despite this, he continued to have reflex bladder contractions that he could feel but could not catheterize himself in time to prevent incontinence. We performed cystometry with dorsal penile nerve stimulation and analyzed data of home use of stimulation. During cystometry, the suppressive effect of electric stimulation on hyperreflexic contractions was reliable and reproducible. The patient could start stimulation on sensing bladder contraction, and the suppression of reflex contraction lasted several minutes after stopping brief stimulation. When using stimulation at home, the rate of leakage between catheterization decreased, and catheterized volume increased significantly.- - - - - - - - - - ranking = 1.4keywords = nerve (Clic here for more details about this article) |
3/21. Neurogenic bladder due to peripheral neuropathy and a visual disturbance in an elderly man with systemic lupus erythematosus.A 63 year old man with central nervous system lupus with a neurogenic bladder and visual disturbance is described. The diagnosis of neurogenic bladder, attributed to peripheral neuropathy, was made on the basis of cystometrography and clinical symptoms. A brain magnetic resonance imaging scan showed gliosis along the cerebral vessels and the optic nerve. This case shows that systemic lupus erythematosus can be accompanied by a peripheral neurogenic bladder and visual disturbance, and that these symptoms may not improve despite the amelioration of other lupus symptoms on treatment with steroids.- - - - - - - - - - ranking = 0.2keywords = nerve (Clic here for more details about this article) |
4/21. Neuroselective current perception threshold evaluation of bladder mucosal sensory function.OBJECTIVE: To evaluate human bladder mucosal sensory function by neuroselective Current perception Threshold (CPT) measures from healthy and neuropathic bladders. methods: Eight healthy volunteers and 38 patients with urinary symptoms underwent conventional urodynamic tests including water-filling cystometry and ice water test. Standardized neuroselective CPT measures were obtained from the left index finger and the mucosa of the posterior bladder wall. Three different CPTs were obtained from each test site using a constant alternating current sinusoid waveform electrical stimulus presented at 2000Hz, 250Hz and 5Hz stimulation frequencies, which could selectively reflect the functions of the large myelinated fibers (A-beta-fiber), the small myelinated fibers (A-delta-fiber), and the unmyelinated fibers (C-fiber), respectively. RESULTS: As the determination of CPT values on the finger skin, the CPT values in the bladder could be determined using the neuroselective measures in all patients but three who had no sensory response (absence of sensation) caused by complete spinal injury. In the 8 patients with detrusor hyperreflexia due to incomplete spinal cord injury (supra-sacral lesion), the bladder CPT value (4.0 /-1.9) at 5Hz was significantly lower (p<0.01) than that in the controls (26.2 /-17.7). In the neurogenic bladders determined to be underactive (n=11, including post pelvic surgery, post infra-sacral level spinal cord injury and diabetes patients), the higher CPT values of bladder mucosal sensory functions were found at 5Hz (p<0.05), 250Hz (p=0.07), and 2000Hz (p<0.05) compared to the controls. CONCLUSIONS: Quantitative neuroselective measurement of CPT values in the human bladder mucosal function was feasible. hypersensitivity or hyposensitivity of the urinary sensory function could be determined using the CPT values in comparison to control. The quantitative neuroselective estimation of the bladder sensory functions in different types of sensory peripheral nerve fibers may contribute to the appropriate selection of therapeutic strategy in patients with urinary sensory dysfunction.- - - - - - - - - - ranking = 0.2keywords = nerve (Clic here for more details about this article) |
5/21. spinal cord repair with acidic fibroblast growth factor as a treatment for a patient with chronic paraplegia.STUDY DESIGN: We present a case of a patient with chronic paraplegia with a complete spinal cord gap resulting from a stabbing injury 4 years ago recovering after an innovative surgical strategy. OBJECTIVES: To demonstrate the clinical outcome of surgical repair with sural nerve graft with fibrin glue containing acidic fibroblast growth factor in a patient with chronic spinal cord injury. SUMMARY OF BACKGROUND DATA: spinal cord injury usually causes permanent disability, and there had been not effective surgical technique to obtain satisfactory functional motor recovery, particularly in chronic patients. Previous studies have revealed that acidic fibroblast growth factor could promote axonal regeneration and reduce neuronal death in adult rats with spinal cord injury. methods: The spinal cord gap at T11 level was bridged with 4 sural nerve grafts that redirected specific pathways from white to gray matter. The grafted area was stabilized with fibrin glue containing acidic fibroblast growth factor. RESULTS: Before the operation, the paraplegia was identified as asia-C, with a motor score for the right and left legs of 12 and 0, respectively, a pinprick score of 77, and 77 on a light touch of left side limbs. His functional status improved from being wheelchair-bound to being able to ambulate independently with a walker 2-and-a-half years after surgery. At this stage, paraplegia was asia-D, with motor scores for the right and left legs of 15 and 12, respectively, 86 for a pinprick, and 86 for a light touch of left side limbs. CONCLUSIONS: This case demonstrated significant motor recovery attained in a patient with chronic paraplegia following a repair surgery with nerve graft and growth factor.- - - - - - - - - - ranking = 0.6keywords = nerve (Clic here for more details about this article) |
6/21. Nerve sheath tumors involving the sacrum. Case report and classification scheme.Nerve sheath tumors that involve the sacrum are rare. Delayed presentation is common because of their slow-growing nature, the permissive surrounding anatomical environment, and nonspecific symptoms. Consequently, these tumors are usually of considerable size at the time of diagnosis. The authors discuss a case of a sacral nerve sheath tumor. They also propose a classification scheme for these tumors based on their location with respect to the sacrum into three types (Types I-III). Type I tumors are confined to the sacrum; Type II originate within the sacrum but then locally metastasize through the anterior and posterior sacral walls into the presacral and subcutaneous spaces, respectively; and Type III are located primarily in the presacral/retroperitoneal area. The overwhelming majority of sacral nerve sheath tumors are schwannomas. Neurofibromas and malignant nerve sheath tumors are exceedingly rare. Regardless of their histological features, the goal of treatment is complete excision. Adjuvant radiotherapy may be used in patients in whom resection was subtotal. Approaches to the sacrum can generally be classified as anterior or posterior. Type I tumors may be resected via a posterior approach alone, Type III may require an anterior approach, and Type II tumors usually require combined anterior-posterior surgery.- - - - - - - - - - ranking = 0.6keywords = nerve (Clic here for more details about this article) |
7/21. Bilateral sixth cranial nerve palsy after unintentional dural puncture.PURPOSE: Bilateral sixth nerve palsy is a known though uncommon complication following dural puncture. The recommended treatment consists of hydration and alternate monocular occlusion. The value and the timing of an epidural blood patch (EBP) for sixth nerve palsy remains controversial as some authors have demonstrated benefits in performing an EBP early in course of the nerve palsy whereas others have not found any advantage when an EBP was performed later. CLINICAL FEATURES: A 40-yr-old woman developed bilateral sixth nerve palsy ten days after an unintentional dural puncture. An EBP was done within 24 hr after the onset of the symptoms and immediate improvement of the diplopia was noted by the patient and confirmed by an ophthalmologist. Complete resolution of the diplopia occurred 36 days after the dural puncture. CONCLUSION: Blood patching within 24 hr of the onset of diplopia may be a reasonable treatment for ocular nerve palsy as it relieved the postdural puncture headache and produced partial improvement of the diplopia.- - - - - - - - - - ranking = 1.8keywords = nerve (Clic here for more details about this article) |
8/21. myoclonus with burning sensation in legs that remits with sympathetic blockade.Two patients with hitherto unrecognized spells of involuntary movements in legs are described. They occurred on dropping off to sleep, were preceded by a burning sensation and resembled myoclonus. Subcutaneous injection of epinephrine reproduced the spells. Neurogenic bladder of uninhibited type was noted on cystometry. Epidural or sympathetic nerve block of the lumbar region relieved all the symptoms including the neurogenic bladder. A few minutes before the spells, a rise in blood pressure and pulse rate was observed in one of the cases. Pathophysiological resemblance to painful legs and moving toes was pointed out, but more widespread involvement of the spinal cord was suspected.- - - - - - - - - - ranking = 0.2keywords = nerve (Clic here for more details about this article) |
9/21. Juvenile diabetes mellitus, optic atrophy, hearing loss, diabetes insipidus, atonia of the urinary tract and bladder, and other abnormalities (wolfram syndrome). A review of 88 cases from the literature with personal observations on 3 new patients.A review of 88 cases from the literature with personal observations on 3 new patients is given of the syndrome featured by juvenile diabetes mellitus, optic atrophy, hearing loss, diabetes insipidus, atonia of the urinary tract and bladder and other abnormalities. The postmortem in one of our cases is mentioned. The pattern of inheritance is autosomal recessive. The interpretation of the data on diabetes insipidus from the literature and in our three patients is also discussed. It can only be stated that neurohypophyseal diabetes insipidus can be a component of the syndrome and that in many cases--particularly in the presence of lesions of the efferent urinary tract--the possibility of nephrogenous diabetes insipidus can not be excluded with certainty. It seems probable that the same mechanism can be held responsible for the lesions of the olfactory, optic, vestibular and cochlear nerves, the hypophyseal form of diabetes insipidus, retarded sexual maturation, abnormal pupillary reaction, myelopathy and the electro-encephalographic, electroneurological and electromyographic changes in the wolfram syndrome. The process underlying this affection of neural structures remains obscure.- - - - - - - - - - ranking = 0.2keywords = nerve (Clic here for more details about this article) |
10/21. adult polyglucosan body disease (APBD).Three patients aged 63, 63 and 74 years had various combinations of progressive lower and upper motor neuron dysfunction, sensory loss, urinary incontinence and dementia. Postmortem examinations in two cases showed moderate cerebral and spinal atrophy, ill-defined areas of incomplete myelin loss in white matter and small necrotic foci in the white matter of gyri, around the basal ganglia and near the dentate nuclei. The main microscopic abnormality was a massive accumulation of PAS-positive polyglucosan bodies (PB) of various sizes and shapes in the cerebral hemispheres, brainstem, cerebellum, spinal cord, nerve roots and nerves. These PB were found in the processes of nerve cells and astrocytes, but not in their perikarya. Similar PB were present in peripheral nerves and in the lungs, heart, liver and kidneys. In the third case, a nerve biopsy revealed several, unusually large, PB in the axons of myelinated fibers. These clinicopathologic features are consistent with adult polyglucosan body disease (APBD) and are distinctive from other conditions in which PB may accumulate. Twelve similar cases have been reported previously. The diagnosis can be made by nerve biopsy. The pathogenesis of APBD is not known, but it may be a polysaccharide storage disease.- - - - - - - - - - ranking = 1.2keywords = nerve (Clic here for more details about this article) |
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