Genital Nerve Research Articles

Patient Controlled Versus Automatic Stimulation of Pudendal Nerve Afferents to Treat Neurogenic Detrusor Overactivity

We investigated whether patients with neurogenic detrusor overactivity can sense the onset of bladder contraction and in turn suppress the contraction by electrical stimulation of the dorsal penile-clitoral nerve. A total of 67 patients with different neurological disorders were recruited to undergo 3 filling cystometries. The first cystometry was done without stimulation. The second cystometry was performed with automatic controlled stimulation based on detrusor pressure. The third cystometry was done with patient controlled stimulation using a push button. Four females and 13 males underwent all 3 fillings. Compared to cystometry 1 average bladder capacity for cystometries 2 and 3 was 60% higher. Compared to peak pressure for cystometry 1 average peak pressure during suppressed contractions for cystometries 2 and 3 was 49% and 26% lower, respectively. The average delay of the onset of stimulation during cystometry 3 with respect to cystometry 2 was 5.7 seconds. The study shows that patient controlled genital nerve stimulation is as effective as automatic controlled stimulation to treat neurogenic detrusor overactivity. Thus, patient controlled stimulation is feasible in select patients, although patients must be trained in the technique.

1336: Dorsal Genital Nerve Stimulation for the Treatment of Refractory Overactive Bladder Symptoms

You have accessJournal of UrologyModerated Poster 41, Tuesday, May 22, 2007, 10:00 am - 12:00 pm1 Apr 20071336: Dorsal Genital Nerve Stimulation for the Treatment of Refractory Overactive Bladder Symptoms Howard B. Goldman, Jeffrey M. Mangel, and Cindy L. Amundsen Howard B. GoldmanHoward B. Goldman More articles by this author , Jeffrey M. MangelJeffrey M. Mangel More articles by this author , and Cindy L. AmundsenCindy L. Amundsen More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(18)31550-7AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "1336: Dorsal Genital Nerve Stimulation for the Treatment of Refractory Overactive Bladder Symptoms." The Journal of Urology, 177(4S), pp. 440–441 © 2016 by American Urological AssociationFiguresReferencesRelatedDetails Volume 177Issue 4SApril 2007Page: 440-441 Advertisement Copyright & Permissions© 2016 by American Urological AssociationMetricsAuthor Information Howard B. Goldman More articles by this author Jeffrey M. Mangel More articles by this author Cindy L. Amundsen More articles by this author Expand All Advertisement PDF DownloadLoading ...

Influence of Preservation Versus Division of Ilioinguinal, Iliohypogastric, and Genital Nerves During Open Mesh Herniorrhaphy: Prospective Multicentre Study of Chronic Pain

Influence of Preservation Versus Division of Ilioinguinal, Iliohypogastric, and Genital Nerves During Open Mesh Herniorrhaphy: Prospective Multicentre Study of Chronic Pain

Influence of Preservation Versus Division of Ilioinguinal, Iliohypogastric, and Genital Nerves During Open Mesh Herniorrhaphy

To evaluate whether the various surgical treatment reserved for ilioinguinal, iliohypogastric, and genital branch of the genitofemoral nerves, during open hernia mesh repair, is effective in reducing chronic postoperative pain. Interest in chronic groin pain following herniorrhaphy has escalated, in recent years, due both to treatment and legal implications. However, much debate still exists concerning which treatment to reserve for the 3 inguinal sensory nerves. A multicentric prospective study involving 11 Italian institutions led to the recruitment of 973 cases of hernioplasty. All surgeons were asked to report whether or not each nerve had been identified and preserved or divided. The main endpoint of the study was the evaluation of moderate to severe chronic pain at 6 months and 1 year. Overall, the presence of groin pain at the 6-month and 1-year follow-up was 9.7% and 4.1%, respectively. Pain was mild in 7.9% and moderate to severe in 2.1%, at 6 months, and mild in 3.6% and moderate to severe in 0.5%, at 1 year. Univariate and multivariate analysis showed that lack of identification of nerves is significantly correlated with presence of chronic pain, the risk of developing inguinal pain increasing with the number of nerves not detected. Likewise, division of nerves was clearly correlated with presence of chronic pain. The present findings indicate that identification and preservation of nerves during open inguinal hernia repair reduce chronic incapacitating groin pain and that, in the majority of patients with chronic pain at 6 months, the pain at 1 year is resolved only with conservative or medical treatment.

Closed Loop Electrical Control of Urinary Continence

Individuals with spinal cord injury or neurological disorders may have neurogenic detrusor contractions at low volumes (bladder hyperreflexia), which cause incontinence and can lead to significant health problems. Bladder contractions can be suppressed by electrical stimulation of inhibitory pathways but continuous activation may lead to habituation of the inhibitory reflex and loss of continence. We determined whether conditional stimulation with electrical stimulation of inhibitory pathways applied only at the onset of nascent bladder contractions allows the bladder to fill to a greater volume before continence is lost compared with continuous stimulation. In 6 alpha-chloralose anesthetized cats cystometry was performed to compare the volume at which continence was lost under the conditions of no stimulation, continuous stimulation and conditional electrical stimulation of inhibitory pathways. PNT ENG was used to detect the onset of bladder contractions and it served as the input to an event triggered control system that regulated conditional stimulation to maintain continence. Conditional stimulation controlled by PNT ENG increased bladder capacity by 36% over no stimulation and by 15% over continuous stimulation (p <0.001 and 0.027, respectively). The event triggered control system decreased stimulation time by 67% compared to continuous stimulation. Conditional electrical stimulation of inhibitory pathways is more effective than continuous stimulation. A control system triggered by PNT ENG can maintain urinary continence.

TREATMENT OF NEUROGENIC DETRUSOR OVERACTIVITY IN SPINAL CORD INJURED PATIENTS BY CONDITIONAL ELECTRICAL STIMULATION

The feasibility of automatic event driven electrical stimulation of the dorsal penile/clitoral nerve in the treatment of neurogenic detrusor overactivity (NDO) was evaluated in individuals with spinal cord injury. The study included 2 women and 14 men older than 18 years with NDO, bladder capacity below 500 ml and complete or incomplete suprasacral spinal cord injury. Detrusor pressure (Pdet) was recorded during ordinary, natural bladder filling. In a similar subsequent recording Pdet was used to trigger electrical stimulation when pressure exceeded 10 cm H2O. Of the 16 patients enrolled in this study 13 had increased bladder capacity together with a storage pressure decrease as a result of automatic, event driven electrical stimulation. In 2 patients stimulation could not inhibit the first undesired contraction, leakage occurred and finally 1 could not tolerate stimulation. During stimulated filling Pdet never exceeded 55 cm H2O. Thus, storage pressure was sufficiently low to prevent kidney damage. An average bladder capacity increase of 53% was achieved. This study demonstrates the feasibility of automatic, event driven electrical stimulation in the treatment of NDO. Although the setup in this experiment is not suitable in a clinical setting, the treatment modality is promising and it warrants further investigation.

Causes, prevention, and surgical treatment of postherniorrhaphy neuropathic inguinodynia: triple neurectomy with proximal end implantation.

The recommended surgical treatment for chronic neuropathic pain after herniorrhaphy has been a two-stage operation including: (a) ilioinguinal and iliohypogastric neurectomies through an inguinal approach and (b) genital nerve neurectomy through a flank approach. Two hundred twenty-five patients underwent triple neurectomies with proximal end implantation to treat chronic postherniorrhaphy neuralgia. Four patients reported no improvement. Eighty percent of patients recovered completely, and 15% had transient insignificant pain with no functional impairment. These results are comparable to the results of the two-stage operation. Simultaneous neurectomy of the ilioinguinal, iliohypogastric, and genital nerves without mobilization of the spermatic cord is an effective one-stage procedure to treat postherniorrhaphy neuralgia. It can be performed under local anesthesia and avoids testicular complications. Proximal end implantation of the nerves prevents adherence of the cut ends to the aponeurotic structures of the groin, which can result in recurrence of the pain. A one-stage surgical procedure resecting all three nerves from an anterior approach avoids a second operation through the flank and successfully treats chronic neuralgia.

How to avoid recurrence in Lichtenstein tension-free hernioplasty

The following key principles of the Lichtenstein tension-free hernioplasty can help avoid recurrence and decrease postoperative pain: (1) Use a large sheet of mesh that will extend approximately 2 cm medial to the pubic tubercle, 3 to 4 cm above Hesselbach’s triangle, and 5 to 6 cm lateral to the internal ring. (2) Cross the tails of the mesh behind the spermatic cord to avoid recurrence lateral to the internal ring. (3) Secure the mesh with two interrupted sutures on the upper edge and one continuous suture with no more than 3 to 4 passes on the lower edge of the mesh to prevent folding and movement of the mesh in the groin. (4) Position the mesh in a slightly relaxed dome shape configuration to counteract the forward protrusion of the transversalis fascia when the patient stands up from the intraoperative supine position. (5) Identify and protect the ilioinguinal, iliohypogastric, and genital nerves throughout the operation.

A 1-stage surgical treatment for postherniorrhaphy neuropathic pain: triple neurectomy and proximal end implantation without mobilization of the cord.

The recommended surgical treatment for chronic neuropathic pain after herniorrhaphy has been a 2-stage operation including: (1) ilioinguinal and iliohypogastric neurectomies through an inguinal approach and (2) genital nerve neurectomy through a flank approach. A 1-stage surgical procedure resecting all 3 nerves from an anterior approach avoids a second operation through the flank and successfully treats chronic neuralgia. A private practice dedicated to abdominal wall hernia surgery in general community hospitals. Between 1995 and 2001, 49 patients underwent triple neurectomies with proximal end implantation to treat chronic postherniorrhaphy neuralgia. Triple neurectomy of the ilioinguinal, iliohypogastric, and genital nerves performed under local anesthesia with implantation of their proximal ends and without mobilization of the spermatic cord. Two patients (4%) reported no improvement. Eighty percent of patients recovered completely, and 16% had transient insignificant pain with no functional impairment. These results are comparable to the results of the 2-stage operation. Simultaneous neurectomy of the ilioinguinal, iliohypogastric, and genital nerves without mobilization of the spermatic cord is an effective 1-stage procedure to treat postherniorrhaphy neuralgia. It is performed under local anesthesia and avoids testicular complications. Proximal end implantation of the nerves prevents adherence of the cut ends to the aponeurotic structure of the groin, which can result in recurrence of the pain.

Pigment-dispersing factor in the locust abdominal ganglia may have roles as circulating neurohormone and central neuromodulator.

Pigment-dispersing factor (PDF) is a neuropeptide that has been indicated as a likely output signal from the circadian clock neurons in the brain of Drosophila. In addition to these brain neurons, there are PDF-immunoreactive (PDFI) neurons in the abdominal ganglia of Drosophila and other insects; the function of these neurons is not known. We have analyzed PDFI neurons in the abdominal ganglia of the locust Locusta migratoria. These PDFI neurons can first be detected at about 45% embryonic development and have an adult appearance at about 80%. In each of the abdominal ganglia (A3-A7) there is one pair of lateral PDFI neurons and in each of the A5-A7 ganglia there is additionally a pair of median neurons. The lateral neurons supply varicose branches to neurohemal areas of the lateral heart nerves and perisympathetic organs, whereas the median cells form processes in the terminal abdominal ganglion and supply terminals on the hindgut. Because PDF does not influence hindgut contractility, it is possible that also these median neurons release PDF into the circulation. Release from one or both the PDFI neuron types was confirmed by measurements of PDF-immunoreactivity in hemolymph by enzyme immunoassay. PDF applied to the terminal abdominal ganglion triggers firing of action potentials in motoneurons with axons in the genital nerves of males and the 8th ventral nerve of females. Because this action is blocked in calcium-free saline, it is likely that PDF acts via interneurons. Thus, PDF seems to have a modulatory role in central neuronal circuits of the terminal abdominal ganglion that control muscles of genital organs.

The role of cercal sensory feedback during spermatophore transfer in the cricket, Acheta domesticus

The role of the cerci in the spermatophore transfer behavior of the cricket Acheta domesticus was examined. During transfer, the male cerci were held close to the female abdomen where they produced small flicking movements. Male cercal ablation significantly decreased mating success by reducing both the ability of the male to hook the epiphallus on to the female subgenital plate and to transfer the spermatophore. During spermatophore transfer, the male must thread the spermatophore tube into the female genital papilla and attach the spermatophore, via its attachment plate, to the base of the ovipositor. Extracellular recordings from the male genital nerve revealed that a centrally driven, rhythmic bursting activity of genital efferents produced the rhythmic contractions of the five pairs of genital muscles responsible for spermatophore threading. Tactile stimulation of campaniform sensilla on the medial aspect of each cercus inhibited the activity of those motor units responsible for advancing the spermatophore tube during threading, while simultaneously activating the motor units responsible for adjusting the position of the epiphallus. We conclude that mechanosensory neurons on the cerci of the male cricket supply important information on female position to the motor program responsible for spermatophore threading and transfer.

Allatotropin-like neuropeptide in the cockroach abdominal nervous system: myotropic actions, sexually dimorphic distribution and colocalization with serotonin.

Allatotropin (AT) was isolated from the moth Manduca sexta as a peptide stimulating biosynthesis of juvenile hormone in the corpora allata, but has also been shown to be cardioactive in the same species. Here, we have investigated the presence and biological activity of AT-like peptide in the cockroaches Leucophaea maderae and Periplaneta americana with focus on abdominal ganglia and their target tissues. An antiserum to M. sexta AT was used for immunocytochemical mapping of neurons in the abdominal ganglia. A small number of interneurons and efferent neurons were found AT-like immunoreactive (AT-LI) in each of the abdominal ganglia. A prominent sexual dimorphism was detected in the terminal abdominal ganglion: in L. maderae the male ganglion there are approximately 18 AT-LI neurons with cell bodies posteriorly and efferent axons in the genital nerves; in the female ganglion 4-5 AT-LI cell bodies (with efferent axons) were found in the same region. Correlated with the extra efferents in males, the male accessory glands are richly supplied by AT-LI fibers and in females a less prominent innervation was seen in oviduct muscle. A similar dimorphism was seen in abdominal ganglia of P. americana. A sexual dimorphism was also detected in the abdominal ganglia A4-A6 of L. maderae. In each of these ganglia, approximately 8-10 large AT-LI neuronal cell bodies were found along the midline; in females these neurons have significantly larger cell bodies than in males. In both sexes, and both cockroach species, two large dorsal midline neurons were detected in A-5 and 6, which seem to send axons to the hindgut: the rectal pads of the hindgut are supplied by arborizing AT-LI axons. In males and females of both species, efferent AT-LI axons from midline neurons in A3-A6 supply the lateral heart nerves and other neurohemal release sites with arborizations. The efferent midline neurons of females contain colocalized serotonin-immunoreactivity. We tested the in vitro actions of M. sexta AT on muscle contractions in the L. maderae hindgut and the abdominal heart of both species. The frequency of contractions in the hindgut increased dose dependently when applying AT at 5 x 10(-8) to 5 x 10(-6) M (maximal response at 5 x 10(-7) M). Also the frequency of contractions of the heart increased by application of AT (threshold response at 5 x 10(-9) M). This effect was more prominent in males of both species (maximal response was a 35-40% increase in males and 10-20% in females). In conclusion, an AT-like peptide is present in neurons and neurosecretory cells of cockroach abdominal ganglia and seems to play a role in control of contractions in the hindgut and heart and also to have some function in male accessory glands and oviduct.

Efferent neurons and specialization of abdominal segments in grasshoppers.

A specialized behavior, oviposition, is produced by the eighth and ninth abdominal segments of female grasshoppers. To begin to understand how these segments produce the behavior, which is not displayed by males or pregenital regions of the abdomen in females, the structure and function of efferent neurons in abdominal ganglia of both sexes were examined. In females, the eighth and ninth segments are specialized differently for oviposition: 20 ovipositor motor neurons were found in the eighth segment, and 26 were found in the ninth segment. Males had fewer motor neurons in their eighth segment, but the same number in the ninth segment, which is the only genital segment in males. However, the axons of several of the ninth segmental male motor neurons traveled to the periphery in the genital nerve, which is only found in males. In both sexes, pregenital ganglia had the most motor neurons, but these neurons, for the most part, had morphologies that strongly resembled those of genital segments. Efferent modulatory neuron numbers were not sexually dimorphic in the segments examined, except that males had a greater number in their ninth segment. Experimental methods that activate oviposition were found to also activate a rhythmical motor pattern in pregenital abdominal segments of both sexes. In females, the pattern was phase-coupled to oviposition, but persisted after the connections with the terminal abdominal ganglion were severed. The preponderance of similarities among efferent neurons and elicited motor activity suggests a common pattern of neural circuitry in the behaviorally diverse abdominal segments of grasshoppers.

Central projections of ovipositor sense organs in the damselfly, Sympecma annulata (Zygoptera, Lestidae).

Central projections of sensilla on different parts of the endophytic ovipositor of the lestid damselfly Sympecma annulata are traced. Sensilla include apical hairs of the stylus (STh), hair rows on the ventral part of the valvula (Vh), and distal campaniform sensilla of upper (ULc) and lower (LLc) ovipositor leaves. Backfilling of afferent fibers, using anterograde cobalt fills, reveals the presence of contralaterally projecting fibers for all organs. The main fiber bundle of the LLc enters the terminal ganglion laterally via the genital nerve, but the fibers from ULc enter via the posterior nerve. Main fiber bundles of both leaves end in a lateral part of the ganglion called the lateral neuromere; they demonstrate that sensory information from the two leaves has the same target area. It is hypothesized that the independent pathways of nerves from upper and lower ovipositor leaves (ULc and LLc) may indicate the phylogenetic origin of these appendages from different abdominal segments-the lower leaf from the 8th and upper from 9th. The convergence of afferent fibers from the sensilla of the different ovipositor parts (median, anterior, and lateral processes) in common ganglionic centers may provide the anatomical basis to account for coordination of the movements of different ovipositor parts during oviposition. © 1994 Wiley-Liss, Inc.

Octopamine-like immunoreactive neurones in locust genital abdominal ganglia

Using a well characterized anti-serum, the distribution of octopamine-like immunoreactive neurones is described in the locust seventh abdominal (A7) and terminal ganglia (TG), which are associated with genital organs. Apart from 4 paired ventral somata occasionally observed in the TG, all labelled cells could be identified as efferent dorsal- and ventral unpaired median (DUM/VUM) neurones by virtue of the characteristic large size and position of their somata, projections of their primary neurites in DUM-cell tracts, and bifurcating axons which arise from dorsal T-junctions and enter peripheral nerves. For the examined ganglia our data indicate that the whole population of efferent DUM and VUM-cells, defined here as progeny of the segment specific unpaired median neuroblast with peripheral axons, are octopaminergic, and that equal numbers of these cells occur in both sexes: 8 in A7 and 11 in TG. Sex-specific differences are probably restricted to the axonal projections of 5 octopamine-like immunoreactive DUM-somata in A7, and 5 in TG, which in females project into their segment specific sternal nerves, but in males into the genital nerve of the TG. Numerous intersegmentally projecting octopamine-like immunoreactive fibres traverse both ganglia. The majority probably stem from previously described octopamine-like immunoreactive neurones in the thoracic and suboesophageal ganglia.

An analysis of free amino acids, neurotransmitters and enzymes in the nervous system of Solpugida (Arachnida)

1. The composition of amino acids, biogenic amines and related enzymes in the brain and other regions of the nervous system was analyzed for the solpugids, Eremobates palpisetulosus and Eremorhax magnus. The most abundant amino acids were Glu, Asp, Pro, Ala and Gly. 2. GABA, dopamine, noradrenaline, acetylcholine and acetylcholinesterase were present in the brain. AChE activity was highest in the protocerebrum and cheliceral nerves; no activity was found in the optic or genital nerves. 3. Concentrations of amines and ACh were found to increase in the brain during postembryonic development.

Rectal sensory evoked potentials: an Assessment of their clinical value

To assess abnormalities of sensory conduction in anorectal disease we have evaluated peripheral sensory perception and somatosensory evoked potentials produced by rectal stimulation in control subjects and patients with either constipation or idiopathic faecal incontinence. Evoked potentials were also recorded after posterior tibial and dorsal genital nerve stimulation. Rectal sensation was also assessed using electrical stimulation. Reproducible evoked potential recordings after anorectal stimulation were possible in only a minority of subjects and when recorded showed intersubject and intrasubject variation. In the constipated group there was a significant difference in rectal electrical sensation (P < 0.05) from controls. We conclude that peripheral sensory testing demonstrates an abnormality in severe constipation. However, cerebral evoked potentials cannot be reliably recorded after rectal stimulation, and when recorded the latencies are of too broad a range to discriminate between health and disease. This probably relates to the difference between somatic and visceral pathways.

Lung inflation evokes reflex dilation of microvessels in rat skeletal muscle

Lung inflation can reflexively decrease peripheral resistance, but effects on the microcirculation have not been determined. In this study, we examined the effects of lung inflation on microvessels in skeletal muscle. In anesthetized spontaneously breathing rats, the right cremaster muscle with intact circulation and innervation was exposed and suspended in a tissue bath filled with a physiological salt solution. Diameters of third-order arterioles (3As) were displayed by television microscopy and measured as an index of microcirculatory resistance. In other experiments, sympathetic activity (in the genital femoral nerve) to the cremaster was recorded. Lung inflation decreased systemic blood pressure by 32 +/- 3 mmHg and increased 3A diameter by approximately 23% (P less than 0.05, n = 17). The increase was abolished by cutting the cervical vagus nerves or the right genital femoral nerve. Furthermore, inflation decreased sympathetic nerve activity by 47.6 +/- 11.3% (P less than 0.05, n = 5) before vagotomy but not after. Dilation in response to inflation was also abolished by phentolamine or guanethidine. These results suggest that stimulation of vagal afferents by inflation reflexively decreases microvascular resistance by withdrawal of sympathetic tone.

Functional status of the sacral spinal cord segments in patients with vertebrogenic pudendal nerve subscapularis syndrome

The aim of our study was to investigate sacral reflex responses in patients with vertebrogenic lesions of the genital nerve. Recording of reflexes that were induced at the level of sacral segments was performed in the supine position of the patient. The study was performed on a 4-channel electromyograph M-42, which allowed recording the response with a significant latent period - up to 500 ms. To distinguish between the evoked response and dipping potentials more accurately, we applied the technique of superimposing several responses.

Structure and distribution of dorsal unpaired median (DUM) neurones in the abdominal nerve cord of male and female locusts.

Dorsal unpaired median (DUM) neurones in insects have been shown to modulate the activity of both skeletal and visceral muscle. It has been suggested that as a population they carry out a role analogous to that of the sympathetic nervous system in vertebrates; however, the extent of their distribution throughout the ventral nerve cord has not been assessed. This paper aims to fill this gap by systematically describing the number and morphology of DUM neurones in each of the abdominal ganglia of male and female locusts. To achieve this, the lateral nerves of each abdominal ganglion were backfilled to reveal the position of the somata of DUM neurones. To confirm their identity and reveal their structure, DUM somata were then impaled with microelectrodes and, after physiological characterization, the neurones were stained by intracellular injection with cobalt ions. In each of the first six abdominal ganglia of both sexes, two DUM neurones, one with axons in the tergal nerve and one with axons in the sternal nerve, were found. In the seventh abdominal, and the terminal, ganglion (composed of the eighth to eleventh neuromeres), there was considerable sexual dimorphism in DUM neurone distribution, which was most marked in those associated with some of the nerves innervating the genitalia. In the male, four clusters of somata in the seventh, eighth, and tenth segments have axons in the genital nerve. In the female, which lacks a genital nerve, clusters of DUM neurones, absent in the male, have axons in the seventh and eighth sternal nerves and the cercal nerve.