Corpus Cavernosum Electromyography Research Articles

THE ROLE OF SILDENAFIL IN THE TREATMENT OF ERECTILE DYSFUNCTION IN PATIENTS WITH PELVIC FRACTURE URETHRAL DISRUPTION

Erectile dysfunction (ED) is a common sequel of pelvic fracture urethral disruption (PFUD). After repair of the urethral injury ED may be the most devastating long-term effect for the patient. Some patients with ED may regain normal erectile function. We prospectively studied the response to sildenafil and the erectile function of patients with ED due to PFUD. The erectile function of patients referred to us with PFUD for urethroplasty were prospectively evaluated before surgery. Patients underwent nocturnal penile tumescence testing and, if results were abnormal, penile duplex ultrasonography with intracavernous injection and arteriography were performed to diagnose the etiology of ED. Patients were questioned about erectile function every 3 months after surgery and if they complained of ED they were offered 100 mg sildenafil. Patients were followed for at least 18 months after surgery. A total of 29 consecutive patients were evaluated and 22 (76%) of them had ED before surgery. Sufficient followup was available for 15 of the patients. Overall 47% of these patients responded favorably to sildenafil. Of the patients 60% with neurogenic ED and 20% of those with arterial ED responded to this treatment. In 33% of the patients ED resolved within the followup period. All patients with spontaneous resolution of ED previously responded to sildenafil (71% of sildenafil responders). In patients with ED due to PFUD, those with neurogenic ED are more likely to respond to sildenafil than those with arterial damage. Favorable response to sildenafil may predict spontaneous resumption of normal erectile function over time.

The methodology of corpus cavernosum electromyography revisited.

The methodology of corpus cavernosum electromyography (CC-EMG) was revisited, in order to overcome current methodological difficulties that hinder its clinical application. Using an 8-channel device, CC-EMG was performed in 12 healthy volunteers. Surface electrodes were placed bilaterally on the penile shaft and the kneecap (reference electrode), the pubis region and the anterior superior iliac spine (ASIS). A band pass filter with cut-off frequencies of 0.1 and 20 Hz was used. At least 2 sessions of recordings were performed in each subject. Thirty-five of 46 recordings were interpretable. Significant time delays between potentials recorded from different sites of the CC were detected. Clear spatial voltage gradients related to CC-potentials were observed on the pubis region. No voltage changes related to CC-potentials, but electrical activity from other sources were recorded from the ASIS. In contrast to frequency, a clear correlation could be demonstrated between amplitude, duration and polyphasity of CC-potentials recorded in 2 different sessions in the same individual. Multichannel monopolar recording of CC-EMG with surface electrodes is practical and has several advantages compared with bipolar recording. The results provide evidence that the recorded signals indeed reflect electrical activity of the CC and therefore offer a basis to pursue further clinical validation studies.

93 Corpus cavernosum electromyography during sleep-related and audiovisual sexual stimulation induced erection

93 Corpus cavernosum electromyography during sleep-related and audiovisual sexual stimulation induced erection

Corpus cavernosum electromyography (CC-EMG) is influenced by multiple factors

Corpus cavernosum electromyography (CC-EMG) is influenced by multiple factors

The value of corpus cavernosum electromyography in erectile dysfunction: current status and future prospect.

In the last decade, several investigators have tried to develop corpus cavernosum electromyography (CC-EMG) as a direct clinical method to evaluate the state of the penile autonomic innervation and the cavernous smooth muscle. Both basic and clinical studies have shown promising results. However, its application as a diagnostic tool with clinical relevance was hindered by insufficient knowledge of cavernous smooth muscle electrophysiology, lack of standardization, technical and practical difficulties and problems in the interpretation of the results. Recently, the European Commission created the so-called COST Action B18 (corpus cavernosum EMG in erectile dysfunction), aiming to strengthen the coordination of the European research groups and give the development of CC-EMG a new impetus. This review presents an overview of the physiological background, the current status of CC-EMG, and discusses possibilities for further developments.

EVOKED CAVERNOUS ACTIVITY

Corpus cavernosum electromyography has been widely done to evaluate autonomic dysfunction in patients with erectile dysfunction. We assessed the value of corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin responses for their accuracy in determining autonomic involvement in cases of erectile dysfunction. We evaluated 75 men with erectile dysfunction by corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin response tests at our neurourology laboratory. The etiology of dysfunction was vascular, neurogenic, psychogenic or mixed based on a detailed medical and sexual history, physical examination, electrophysiological and laboratory studies, penile color Doppler ultrasonography, and cavernosography and/or cavernosometry. Autonomic involvement was clinically assessed by systemic findings, such as orthostatic hypotension, impaired gastrointestinal motility, sinus dysrhythmia and secretomotor changes. A concentric electromyography needle placed in the right cavernous body was used to record corpus cavernosum electromyography and evoked cavernous activity. The right median nerve was stimulated electrically with 13 to 16 mA. to determine evoked cavernous activity and the penile sympathetic skin response. The latter response was recorded with silver disc electrodes placed on the left cavernous body. All tests were performed using an electromyography/evoked potential machine. We determined the relationships among corpus cavernosum electromyography, evoked cavernous activity and penile sympathetic skin response tests in respect to etiological factors. The 56 patients with normal corpus cavernosum electromyography activity had also evoked cavernous activity and a penile sympathetic skin response except for 1 with no penile sympathetic skin response but evoked cavernous activity. None of these patients had autonomic neuropathy. Of the 19 patients without corpus cavernosum electromyography activity 11 had evoked cavernous activity, including 10 with no autonomic neuropathy. The remaining 8 patients had no evoked cavernous activity, of whom 7 had autonomic neuropathy. A penile sympathetic skin response was recorded in 18 men with absent corpus cavernosum electromyography. Due to false-negative results on corpus cavernosum electromyography and penile sympathetic skin response testing evoked cavernous activity seems more reliable for determining autonomic involvement in the pathophysiology of erectile dysfunction.

Relaxation degree: a new concept in erectile dysfunction.

To investigate the clinical application of the new parameter' Relaxation Degree. Chart reviews of 150 patients were evaluated retrospectively of whom 96 had been diagnosed as pure cavernoocclusive dysfunction (COD) by using corpus cavernosum electromyography (CC-EMG) and cavernosometry and of whom 54 had been diagnosed as psychogenic erectile dysfunction by normal CC-EMG; cavernosometry and pulse doppler scanning. Relaxation degree was defined as the percent decrease in the amplitudes of the electrical activity of corpus cavernosum (EACC). Mean relaxation degree measurements were found as 66.5%, 66.28% and 16% in minimal, moderate and severe COD groups respectively. This value was 80% in psychogenic erectile dysfunction group. Statistical comparisons were found significant between minimal and severe and moderate and severe COD groups. All three organic erectile dysfunction groups were also compared with psychogenic erectile dysfunction group where differences were found significant. If the normal relaxation degree was accepted as more than 80%, COD could be diagnosed with 93% specificity and 98% sensitivity without performing cavernosometry. Relaxation degree parameter could be used in diagnosis of COD showing the percent relaxation ability of the cavernous smooth muscle as a non invasive method when compared with cavernosometry.

The role of corpus cavernosum electromyography.

Although corpus cavernosum electromyography presents great theoretical appeal as a possible direct clinical measure of penile neurogenic function, it has still not been adopted as a routine diagnostic test in the evaluation of patients with erectile dysfunction. This is because of the considerable technical and interpretative problems associated with the method. This review covers some of the more important research and clinical papers published since its first description in 1989, with a special focus on recent advances in this field.

PATIENT SELECTION CRITERIA IN THE SURGICAL TREATMENT OF VENO-OCCLUSIVE DYSFUNCTION

Purpose We evaluated short and long-term results of simple and complex venous surgery in patients with veno-occlusive dysfunction unresponsive to maximum recommended doses of intracavernous alprostadil, who were selected with newly developed diagnostic indicators. Materials and Methods A total of 23 impotent men with a mean age of 41 years (range 20 to 50) underwent complex penile venous surgery. Only patients fulfilling at least 3 criteria were included in study. The criteria were mild cavernous leak assessed by cavernosometry (grades 1 and 2), more than 30% cavernous smooth muscle tissue (histomorphometric analysis), normal analogical corpus cavernosum electromyography recordings according to international standards, cavernosal oxygen tension greater than 65 mm. Hg at erection and age younger than 50 years. Results Of 23 patients 17 (74%) had normal erections within a year after surgery, and 5 of them (29%) complained of recurrent erectile dysfunction. At long-term followup 6 of 12 patients had spontaneous erections. Conclusions Careful selection with advanced diagnostic techniques should be mandatory before performing venous surgery in patients with high degree veno-occlusive dysfunction as the only alternatives are major therapeutical solutions.

Erectile dysfunction. Its diagnosis and treatment

Erectile dysfunction is a health problem affecting more than 50% of men between 40 and 70 years old. Although several therapeutic options have become available in the last 20 years, only a small percentage of the patients, perhaps no more than 10%, seek treatment. The recent introduction of oral and intra-urethral medication has been highly publicised, therefore more patients will be involved in this new wave of enthusiasm for non-invasive options. We are challenged to develop new options as to how to present these treatments to our patients. Traditionally the diagnosis of erectile dysfunction is based on a comprehensive evaluation regarding aetiology, including family and sexual history, physical examination, blood tests, pharmacological testing with vasoactive drugs and Doppler study of the penile arteries. Other studies, such as Rigiscan, corpus cavernosum electromyography, cavernosometry, cavernosography and penile angiography should be performed when indicated. With regard to treatment, penile intracavernosal injection remains the best nonsurgical treatment. Application of a vacuum device and penile prosthesis implantation are also reliable therapeutic options. Only a limited number of patients are suitable for arterial revascularization or penile venous surgery. However, in the near future, we will have to face the requests of our patients for an oral or topical prescription without concern for the cause of erectile dysfunction. The results of these new therapies on organic impotence are not as exciting, but warrant further studies.

Caverno-Occlusive and Autonomic Dysfunction: A New Concept in Young Patients

We attempted to identify the etiology of erectile dysfunction in 50 male patients with a mean age of 31.4 (25–42) years. The physical and neurological examinations, history, biochemistry and serum testosterone and prolactin levels were within normal limits. Pharmacopenile duplex ultrasonography, corpus cavernosum electromyography (CC-EMG) and cavernosometry were performed. Smooth muscle tone and the relaxation response after intracavernous papaverine and sodium nitroprusside injections were evaluated by CC-EMG. Autonomic dysfunction has been defined as increased electrical activities after visual sexual stimulation and lowered amplitudes despite normal smooth muscle content. Our definition is similar to this: paradoxically increased electrical activities after intracavernous injection. Caverno-occlusive dysfunction (COD) and accompanying pathologies were found in 38 patients (76%) with pure COD in 26 (52%), COD and arterial pathology in 2 (4%) and COD + autonomic dysfunction in 10 patients (20%). Amplitudes of cavernous electrical activity were low in 32 of 38 patients with COD. These high COD and autonomic dysfunction rates led us to examine these pathologies on molecular and electrophysiological bases.

Comparative Study between Corpus Cavernosum‐Electromyography Findings and Electron Microscopy of Cavernosal Muscle Biopsies in Erectile Dysfunction Patients

Biopsy and electrical activity recordings of the corpus cavernosum are 2 new diagnostic methods for the evaluation of impotent men. We evaluated the corpus cavernosum ultrastructure and electromyography (EMG) recordings from patients with erectile dysfunction. Twenty erectile dysfunction patients with veno-occlusive dysfunction underwent a detailed history, physical examination, biochemical tests, hormonal analysis, injection of an intracavernous vasoactive agent (60 mg papaverine-HCl), color penile Doppler ultrasonography, cavernosometry/ cavernosography and corpus cavernosum electromyography (CC-EMG). Thirteen patients underwent total vein ligation and 7 had penile prosthesis implantations. Tissue samples were obtained during surgery from both corpora cavernosa and examined by transmission electron microscopy. Control corporal tissue samples were taken from 3 cadavers. In 15 patients, CC-EMG recordings were 15.6 +/- 0.65 microV in the flaccid state, which decreased in 13 patients after papaverine (5.61 +/- 0.25 microV; P < 0.001). Five patients with diabetes mellitus had low amplitudes in the flaccid state (5.26 +/- 0.45 microV), which did not vary significantly after a papaverine injection (4.99 +/- 0.75 microV). The pathology of the corpus cavernosum biopsy specimens revealed a smooth muscle cell thickened basal membrane, dilated rough endoplasmic reticulum, and increased numbers of fibroblasts, but ultrastructurally normal endothelial cells lining the sinusoids. There was no difference between samples from diabetic or nondiabetic patients, or from either side of the corpora cavernosa. The only pathologic change observed in the controls was mitochondrial swelling. CC-EMG is less invasive and a valuable method in patients with erectile dysfunction, whereas no specific findings were observed from penile biopsy specimens.

The role of electrophysiological evaluation in erectile dysfunction

A better understanding and greater usefulness of corpus cavernosum electromyography in the work-up of erectile dysfunction has recently been demonstrated. Technical precision and indications have been made of other neurophysiological tests, such as skin sympathetic responses, pudendal evoked responses and sensory conduction velocity of the dorsal nerve of the penis, and will be reviewed in this article.

Single Potential Analysis of Corpus Cavernosum Electromyography for the Assessment of Erectile Dysfunction: Provocation, Reproducibility and Age Dependence-Findings in 36 Healthy Volunteers and 324 Patients

Purpose Corpus cavernosum electromyography is a controversial method for assessing erectile failure. For its application as a diagnostic tool with clinical relevance, intra-individual stability of the parameters in independent recordings as well as information about provocation and age dependence are required. Materials and Methods We investigated reproducibility, provocation and age dependence of 11 parameters of single potential analysis of corpus cavernosum electromyography for 36 healthy volunteers in 2 independent recordings with surface electrodes using a visual evaluation technique. Recording 1 results were compared to findings for 324 men with erectile dysfunction. Results In healthy subjects all parameters varied extremely among individuals and they were poorly reproducible at repetition. The definition of a normal range as mean plus or minus 2.5 standard deviations did not result in useful diagnostic criteria for individual cases. Activity was not age dependent. Significant differences between healthy and impotent men as defined groups were found in provocation (overall maximum likelihood chi-square 15.5, dF = 2, p <0.0005). Conclusions Single potential analysis of corpus cavernosum electromyography seems to be appropriate for distinguishing potent volunteers from patients with erectile dysfunction. Provocation of slow cavernous electric activity seems to be a promising parameter that should be considered for ongoing studies. However, a high range of variation of findings even intra-individually does not currently qualify the method for routine clinical use. Further research will show whether different means of documentation or evaluation, that is corpus cavernosum electromyography pattern analysis at rest after audiovisual sexual stimulation, drug application or digital conversion of data, will lead to better results.

Single Potential Analysis of Corpus Cavernosum Electromyography for the Assessment of Erectile Dysfunction

Single Potential Analysis of Corpus Cavernosum Electromyography for the Assessment of Erectile Dysfunction

Progress in corpus cavernosum electromyography (CC-EMG)-third international workshop on corpus cavernosum electromyography (CC-EMG).

Corpus cavernosum electromyography (CC-EMG) is currently used in most European centres dealing with erectile dysfunction, both on account of experimental applications and the early findings of clinical results. In this particular field, experimental research and clinical practice, on selected patients, have been elaborated in parallel, revealing the relationships between cavernous electrical activity and the integrity of autonomic ortho- and parasympathetic nervous systems of the genital organs. A relationship has also been demonstrated between the functional status of the cavernous smooth muscle and cavernopathies, which, at present, cannot be evaluated with the other diagnostic methods currently available. The first Workshop on CC-EMG was held in Mannheim, Germany, in 1993 and this represents a true milestone in this particular field. It was on that occasion that the denomination (CC-EMG) and the standardization of the technique were decided upon by the pioneers of electromyographic studies 1 .I n fact, during the consensus meeting, the main technical and clinical parameters were established in order to obtain homogeneous recordings and comparable results between different Centres. During the second Workshop, held in Hannover, Germany in 1994, the range of electrical recordings from homogeneous series of normal patients have been established on the basis of analogic methods of tracing and interpretation. Moreover, the early recordings employing conversion and digital analy

Corpus cavernosum electromyography (CC-EMG): a new technique in the diagnostic work-up of impotence.

We have studied cavernous electrical activity in 42 subjects, healthy volunteer controls and groups of impotent patients using a nonspecific electromyographic device (PICO-MENFIS) and a specific one, the SPACE-recorder 7500 designed to achieve electric recordings from the corpora cavernosa. In all of the patients, we detected under basal conditions a mean amplitude of 583 +/- 323 microV, a mean duration of 4.9 +/- 7 s, a mean polyphasicity of 3.5 +/- 1.4. It should be emphasized that a significant reduction of potential amplitudes was recorded after pharmacological stimulation in both the controls and the impotent patients. The healthy controls showed amplitudes significantly higher than the impotent patients after radical cystectomy (715 +/- 141 microV versus 381 +/- 227 microV, p < 0.01). The patients after a "nerve-sparing" radical cystectomy with a mean amplitude similar to the controls (500-700 microV) reacted well to the intracavernous drugs in a high percentage of cases. In our experience, CC-EMG seems to be a reliable method which can pinpoint directly lesions to the cavernous smooth muscle and penile autonomic nerves. It has also been able to assess the effects of stress, anxiety and pain on the erectile mechanisms.

Electromyographic Changes of Corpus Cavernosum Due to Papaverine and Nitroprusside in Veno-Occlusive Dysfunction

Purpose We compared electrical activity of the corpus cavernosum after intracavernous papaverine and nitroprusside injections. Some aspects of the androgen modulator system in patients with veno-occlusive dysfunction are discussed. Materials and Methods Electromyography of the corpus cavernosum was performed before and 1 day after intracavernous injection of 60 mg. papaverine and 400 microgram sodium nitroprusside in 22 patients with veno-occlusive dysfunction. Changes in duration and amplitude of electromyographic potentials were compared in groups with and without incoordination patterns. Results The decreases in electrical amplitude and duration in 15 patients with a negative incoordination pattern, and increases in 7 with a positive pattern were more significant with intracavernous sodium nitroprusside than with papaverine injections. Conclusions Electromyographic changes were more prominent with nitroprusside than with papaverine, which demonstrates the use of nitroprusside when performing corpus cavernosum electromyography.

Multifactorial evaluation of diabetic erectile dysfunction.

We determined arterial venous and sinusoidal factors in 20 patients with insulin dependent diabetes mellitus and erectile dysfunction by performing dynamic infusion cavernosometry (DIC), colour flow Doppler ultrasonography, penile biothesiometry and corpus cavernosum electromyography (CCE). DIC, colour flow Doppler ultrasonography and penile biothesiometry were done in standard fashion except for CCE. Paradoxical increase in the electrical activity of corpus cavernosum after intracavernous (IC) papaverine was called a discoordination that was due to cavernous smooth muscle contraction instead of relaxation. Arterial and accompanying pathologies were found in 10 (50%) patients. In 3 (15%) of them pure arterial pathology, in 6 (30%) patients arterial and veno-occlusive dysfunction (VOD) and in one patient arterial pathology with abnormal biothesiometry were found. VOD and accompanying pathologies were found in 12 (60%) patients. In 6 (30%) of them VOD and arterial, in 4 (20%) patients VOD and discoordination and in 2 (10%) patients VOD and abnormal biothesiometric values were present. A higher frequency and coexistence of VOD and discoordination pattern were observed. In conclusion, patients with diabetic impotence show a wide range pathophysiology of erection and the evaluation of these patients must include multistep techniques.

Corpus Cavernosum Electromyogram: Spontaneous and Evoked Electrical Activities

Sympathetic skin responses recorded from the surfaces of limbs and the penis resemble the waveforms recorded by needle from the corpora cavernosa. Thus, corpus cavernosum electromyography might reflect a systemic sympathetic response rather than unique smooth muscle corporeal activity. We recorded electrical activity simultaneously from the corpora and limbs of 10 subjects. Spontaneous activity was unique to the corpora, while electrical activity in response to sympathetic activating maneuvers was found simultaneously in the corpora and limbs (Fisher's exact test, p < 0.001). It is concluded that 2 types of electrical activity can be recorded from the corpora--spontaneous activity, which might reflect specific smooth muscle activity, and response activity, which is part of the systemic response to sympathetic stimulation.