The Role of Nocturnal Penile Tumescence and Rigidity (NPTR) Monitoring in the Diagnosis of Psychogenic Erectile Dysfunction: A Review

Sex Med Rev. 2019 Jul;7(3):442-454. doi: 10.1016/j.sxmr.2018.10.005. Epub 2019 Jan 4.


Introduction: Nocturnal penile tumescence and rigidity (NPTR) monitoring with RigiScan was considered one of the most reliable methods to differentiate psychogenic erectile dysfunction (pED) from organic ED. However, its reliability has been questioned because of some limitations in the practice.

Aim: To present contemporary views on the role of NPTR monitoring in the diagnosis of pED.

Method: We performed a comprehensive review of English-language literature on NPTR and pED by a PubMed search.

Main outcome measures: Studies were included if the mechanisms of pED and nocturnal erection and the practice of NPTR monitoring in ED were the main research contents.

Results: The pED results from not only psychosocial factors but also physiological changes containing central nervous abnormality. NPTR monitoring with RigiScan is still considered a useful method for the diagnosis of pED. A normal NPTR recording in a man with ED complaints probably suggests pED, whereas an abnormal recording may represent organic ED. Radial rigidity of no more than 60% is correlated well with axial rigidity, but, when it is more than 60%, the correlation between them is questioned. The consistency between NPTR and sex-stimulated erection is questionable, and the correlation of NPTR with different patient-reported outcome scoring systems is different. A normal NPTR recording in patients with ED does not necessarily mean pED, especially in patients with spinal cord injury. NPTR recordings can be influenced by depression, smoking, aging, negative dream content, and sleep disorders.

Conclusion: NPTR monitoring with the RigiScan is still considered a useful diagnostic tool for pED at the present stage. However, there are some disputes regarding the correlation between penile radial rigidity and axial rigidity and between NPTR and sex-related erection, as well as normative evaluation criteria for ED and the possibility of a false NPTR result, that need to be further studied. Zou Z, Lin H, Zhang Y, et al. The Role of Nocturnal Penile Tumescence and Rigidity (NPTR) Monitoring in the Diagnosis of Psychogenic Erectile Dysfunction: A Review. Sex Med Rev 2019;7:442-454.

Keywords: Diagnosis; Erectile Dysfunction; Nocturnal Penile Tumescence and Rigidity; Penis.

Publication types

  • Review

MeSH terms

  • Erectile Dysfunction / diagnosis*
  • Erectile Dysfunction / etiology
  • Erectile Dysfunction / physiopathology
  • Humans
  • Male
  • Monitoring, Physiologic / methods*
  • Penile Erection / physiology*
  • Penis / physiopathology*
  • Reproducibility of Results
  • Stress, Psychological / complications*
  • Stress, Psychological / physiopathology