THE DIAGNOSIS OF IMPOTENCE

Report 4. Criteria for Assessment of Nocturnal Penile Tumescence

Abstract

The recorded data obtained through monitoring nocturnal penile tumescence (NPT) is an objective method for determining the erectile status of patients who complain of impotence. But, the validity of NPT as a means of distinguishing between functional and organic impotence has not been firmly established. Recently, many authors have assessed NPT on the basis of penile circumferense. Because of the periodic occurrence of NPT in association with rapid eye movement sleep, periodicity shold also be considered an important aspect of NPT.
Therefore, we devised a classification standard for NPT on the basis of periodicity and degree of distention and compared the results with clinical appraisais and data obtained during treatment. The following results were obtained.
1. Five healthy adults who all displayed periodic, vigorous NPT were classified as MSIa.
2. Of 21 patients complaining impotence, 7 were classified as MSIa, 2 with periodicity but week NPT were classified as MSIb, 6 with no periodicity but strong NPT as MSIIa, 3 who displayed no periodic and week NPT as MSIIb, 1 with hardly any NPT as MSIII, and 2 without any observable NPT as MSIV.
3. When these results are compared with clinical findings, it is certain that MSIa represents functional, and MSIII and MSIV organic impotence. In the cases of MSIb and MSII, however, it can not be decided, on the basis of NPT alone, whether they represent functional or organic impotence.
The recorded NPT data provides an excellent method for diagnosing potency, follow-up studies of a much larger sample are needed to adequately assess such data. The classification standard devised for this study may be thought of as a servic eable, objective way of expressing recorded NPT.