There are three different types of muscle cells in the human body: striated, cardiac, and smooth muscle. In routine clinical studies, the electrical activity of cardiac muscle (electrocardiography, ECG) and of striated muscle (electromyography, EMG) has been registered for decades. The electrical activity of smooth muscle organs, such as the ureter,<sup>4 Golenhofen K., Hannappel J. Normal spontaneous activity of pyeloureteral system in guinea-pig Pflugers Arch 1973 ;  341 : 257-264  [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> uterus,<sup>24 Wagner G. Electrical and mechanical activity in myometrial grafts in the rabbit Acta Physiol Scand 1969 ;  76 : 1A-9A

Cliccare qui per andare alla sezione Riferimenti</sup> colon,<sup>18 Riezzo G., Maselli M.A., Pezzolla F. , e al. In vitro electro-mechanical activity of the human colon: Simultaneous recording of the electrical patterns of the two muscle layers Arch Int Physiol Biochim Biophys 1992 ;  100 : 93-109

Cliccare qui per andare alla sezione Riferimenti, 28 Ward S.M., Keller R.G., Sanders K.M. Structure and organization of electrical activity of canine distal colon Am J Physiol 1991 ;  260 : G724-G731

Cliccare qui per andare alla sezione Riferimenti</sup> duodenum,<sup>1 Bayguinov O., Vogalis F., Morris B. , e al. Patterns of electrical activity and neural responses in canine proximal duodenum Am J Physiol 1992 ;  263 : G887-G895

Cliccare qui per andare alla sezione Riferimenti</sup> gaster,<sup>17 Renzetti M.L., Wang M.B., Ryan J.P. Electrical slow-wave activity from the circular layer of cat terminal antrum Am J Physiol 1991 ;  261 : G78-G89

Cliccare qui per andare alla sezione Riferimenti</sup> trachea,<sup>12 Kondo T., Tamura K., Onoe K. , e al. In vivo recording of electrical activity of canine tracheal smooth muscle Appl Physiol 1992 ;  72 : 135-144

Cliccare qui per andare alla sezione Riferimenti</sup> gall bladder,<sup>13 Konture J.W., Scott G.W., Kingma Y.J. Electrical activity of canine gallbladder J Physiol Pharmacol 1991 ;  42 : 85-92

Cliccare qui per andare alla sezione Riferimenti</sup> and vessels,<sup>11 Kitamura K., Suzuki H., Ito Y. , e al. Similarity and diversity of electrical activity in vascular smooth muscles Prog Clin Biol Res 1990 ;  327 : 257-266

Cliccare qui per andare alla sezione Riferimenti</sup> has been registered mainly in a laboratory setting. Smooth muscle EMG did not find widespread clinical use because the previously mentioned organs required surgical exposition before EMG could be performed. In 1988 Gerstenberg and Wagner described registration of the electrical activity of the cavernous smooth muscle.<sup>3 Gerstenberg T.C., Nordling J., Hald T. , e al. Standardized evaluation of erectile dysfunction in 95 consecutive patients J Urol 1989 ;  141 : 857-861

Cliccare qui per andare alla sezione Riferimenti, 26 Wagner G., Gerstenberg T., Levin R.J. Electrical activity of corpus cavernosum during flaccidity and erection of the human penis: A new diagnostic method? J Urol 1989 ;  142 : 723-727

Cliccare qui per andare alla sezione Riferimenti</sup> Subsequently, corpus cavernosum EMG (CC-EMG) attracted much scientific attention because the information on cavernous autonomic innervation and smooth muscle function was crucial for therapeutic decision making in erectile dysfunction.<sup>2 Bührle C.P., Jünemann K.P., Schmid P. , e al. Corpus cavernosum electromyography in the dog Akt Urol 1993 ;  24 : 214-221

Cliccare qui per andare alla sezione Riferimenti, 14 Merckx L., Schmedding E., de Bruyne R. , e al. Penile electromyography in the diagnosis of impotence Eur Urol 1994 ;  25 : 124-130

Cliccare qui per andare alla sezione Riferimenti, 21 Stief C.G., Djamilian M., Schaebsdau F. , e al. Single potential analysis of cavernous electrical activity—a possible diagnosis of autonomic impotence? World J Urol 1990 ;  8 : 75-81

Cliccare qui per andare alla sezione Riferimenti, 26 Wagner G., Gerstenberg T., Levin R.J. Electrical activity of corpus cavernosum during flaccidity and erection of the human penis: A new diagnostic method? J Urol 1989 ;  142 : 723-727

Cliccare qui per andare alla sezione Riferimenti</sup> These clinical studies were corroborated by experimental data,<sup>8 Höppner C., Stief C.G., Jonas U. , e al. Rabbit penile corpus cavernosum: Electrical and mechanical activity of isolated strips. Investigative Urology V New York: Chapman and Hall, Weinheim (1994).  189

Cliccare qui per andare alla sezione Riferimenti, 15 Moreno A.P., Campos de Carvalho A.C., Christ G. , e al. Gap junctions between human corpus cavernosum smooth muscle cells: Gating properties and unitary conductance Am J Physiol 1993 ;  264 : C80-C86

Cliccare qui per andare alla sezione Riferimenti, 16 Noack T.H., Lammel E., Niederste-Hollenberg A. , e al. Spontaneous depolarizations in single smooth muscle cells from rabbit penile corpus cavernosum Pflügers Arch 1993 ;  422 (suppl) : R81

Cliccare qui per andare alla sezione Riferimenti</sup> suggesting an important role for CC-EMG in the diagnosis of erectile dysfunction.

Conflicting reports appeared in the literature on normal and abnormal CC-EMG recordings owing to a missing consensus on the basic principles of the examination and the recording parameters. To unify the efforts to improve CC-EMG and to allow reproducible and comparable recordings, consensus meetings were held and internationally accepted standards agreed upon.<sup>9 Jünemann K.P., Bührle C.P., Stief C.G. Current trends in corpus cavernosum EMG: Conclusions of the First International Workshop on Smooth Muscle EMG Recordings/Leiomyogram, April 15 to 17, 1993, Mannheim, Germany Int J Impot Res 1993 ;  5 : 105-111

Cliccare qui per andare alla sezione Riferimenti, 22 Stief C.G., Jünemann K.P., Kellner B. , e al. Consensus and progress in corpus cavernosum-EMG Int J Impot Res 1994 ;  6 : 177-183

Cliccare qui per andare alla sezione Riferimenti</sup> Currently, there is a broad consensus among European centers involved in research on CC-EMG. Interest in broader urologic or sexologic areas remains limited owing to a lack of financial resources, and available therapeutic options for many causes of eractile dysfunction dramatically have reduced the need for diagnostic procedures.