Comparative Study between Corpus Cavernosum-Electromyography Findings and Electron Microscopy of Cavernosal zyxw Muscle Biopsies in Erectile Dysfunction Patients zyxw M. Murat BaSar,'* Mustafa F. Sargon,2 Halil BaSar,' Ali Atan,' Fikri Ak,3 H. Hamdi zyxwvut Celik,2 Ruhgun BaSar12 and Zuhal Akalin' Clinics of 'First Urology, and 3Neurology, Ankara Numune Hospital, Ankara, Turkey, and *Department of Anatomy, Medical School Hospital, Hacettepe University, Ankara, Turkey Background: 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. Methods: 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-HCI), 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. Results: In 15 patients, CC-EMG recordings were 15.6 zyxwvu f 0.65 zyxwvu pV in the flaccid state, which decreased in 13 patients after papaverine (5.61 2 0.25 pV; P< 0.001). Five patients with diabetes mellitus had low amplitudes in the flaccid state (5.26 f 0.45 pV), which did not vary significantly after a papaverine injection (4.99 f 0.75 pV). 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 mitochondria1 swelling. Conclusion: CC-EMG is less invasive and a valuable method in patients with erectile dysfunction, whereas no specific findings were observed from penile biopsy specimens. Int J Urol zyxw 1998;5:252-255 Key words: impotence, electron microscopy, penis, smooth muscle, corpus cavernosum-EMC INTRODUCTION Penile erection is a complex psycho-neurovascular phe- nomenon involvingnot only the coordination of zyxwvut 3 main hemodynamic events, but also the interaction of nerves, neurotransmitters, striated and smooth muscle, and the tunica albuginea. Spontaneous smooth muscle cell activation is controlled by the autonomic nervous sys- tem in the corpus cavernosum and was initially de- scribed by Eckhard in 1863 as mentioned in Stief and Merckx's study.2In vitro studies demonstrated that the electrical activity of the corpus cavernosum is related to contractile activity, and occurs with the electrical depo- larization of the cell membranes. However, the use of these findings in clinicalpractice began after the electri- Received Dec. 20, 1996; accepted for publication in revised form Dec. 12, 1997. *Correspondence and requests for reprints to: Baglar Caddesi, 9/3, Seyranbaklan, Ankara 06670, Turkey. cal activity of the corpus cavernosum was r e ~ o r d e d . ~ ~ ~ Recent findings suggest that corpus cavernosum elec- tromyography (CC-EMG) can be used in the diagnosis of cavernosal autonomic neuropathy and cavernosal smooth muscle cell degeneration as a minimally-inva- sive p r o c e d ~ r e . ~ ? ~ Veno-occlusive dysfunction (VOD) is an important cause of organic erectile dy~function.'.~ Penile vascular surgical procedures can only be performed in a small percentage of VOD patients due to largely unsuccessful long-term Recently, CC-EMG has been re- ported to be a reliable diagnostic criterion prior to surgery in patients with VOD.6 However, a penile biopsy also shows the histopathology of the smooth muscle cells in the corpus cavernosum.'0-12 In this study, we evaluated the ultrastructure of the corpus cavernosum from biopsy specimens and CC- EMG recordings from patients with erectile dysfunc- tion of varied etiologies. zyxw 252 091 9-81 72/98/0503-0252/US$3.00 0 JUA/CLJ 1998