The range of diagnostic tools currently available has undoubtedly improved the possibilities for recording organic pathological findings. A probationary therapy without corresponding previous diagnostics therefore appears obsolete; it deprives the patient of the possibility of a cause-oriented therapy of his complaints. Since up to 50% of adult men may experience transitory erectile dysfunction during their lifetime, the exclusion of pathological organic-pathological findings also appears to be significant for the individual, partially disturbed patient. On the other hand, the abundance of diagnostic possibilities must not claim to see through the complexity of the erectile mechanism in all details.
An inconspicuous clinical workup including all diagnostic possibilities can ultimately only result in the finding of an undetectable organic pathological substrate, whereby a free space of diagnostic uncertainty that cannot be precisely delimited will remain; a final assessment may only be possible based on follow-up analyses. Moreover, the relevance of detected pathological examination parameters cannot always be estimated in individual cases. The pathological measurement velocity in a profunda artery or the angiographically proven vascular stenosis naturally speaks for the fact that the patient has an arterial circulatory disorder of the penile vessels as the cause of his complained erectile dysfunction.
But how is this to be evaluated retrospectively when the same patient, seen six months later, reports a spontaneous recovery of his erectile function? The limits of understanding the erectile mechanism and the coincidence of organic and psychogenic factors require a certain caution in the interpretation of collected findings in order not to appear dubious as an examiner and therapist. However, this in no way casts doubt on the value of diagnostic clarification, since the limits of diagnosis and therapy represent an all too familiar, everyday problem in the field of medicine.
Advanced diagnostics are generally reserved for special centers. The indication for further clarification are ambiguities after completion of the basic diagnostics, special therapy options such as revascularization operations as well as expert opinion questions. In addition to duplex sonography, which is not widely used because of the cost factor, invasive penile angiography can be used to obtain additional information regarding the arterial supply to the corpus cavernosum.
Gadolinium-enhanced magnetic resonance imaging is currently in the experimental stage regarding the assessment of arterial perfusion of the corpus cavernosum. Video-urodynamic measurement may provide evidence of autonomic neuropathy as a possible cause of erectile dysfunction. The direct derivation of electrical potentials from the corpus cavernosum (SPACE) is currently being discussed as an examination method for detecting penile neuropathies and myopathies.
Nocturnal tumescence measurements are still important in the field of expert opinion, whereby misinterpretations must be considered. Penile plethysmography and penile scintigraphy are currently irrelevant for the clarification of erectile dysfunction.