Lasers in Medical Science

, Volume 31, Issue 1, pp 57–65 | Cite as

Probe-based confocal laser endomicroscopy (pCLE): a preclinical investigation of the male genital tract

  • Matthias Trottmann
  • Ronald Sroka
  • Herbert Stepp
  • Bernhard Liedl
  • Armin J. Becker
  • Christian G. Stief
  • Sabine Kölle
Original Article


The aim of this study was to assess the potential of probe-based confocal laser endomicroscopy (pCLE) as a new diagnostic imaging technique for the male genital tract. For this purpose, testes, epididymides, and vasa deferentia were obtained during transsexual surgery of healthy patients (n = 10, 26–52 years). Prior to this, testes of rats (n = 10, Sprague–Dawley) and mice (n = 8, wild-type) were examined. Ex vivo tissues were investigated by pCLE after topical fluorescence staining. Images and pCLE real-time video sequences were compared to images acquired by confocal laser scanning microscopy (CLSM); this allowed the identifying of corresponding microstructures. Interestingly, the seminiferous tubules of transsexual humans contained mainly spermatogonia due to long-term estrogen treatment, whereas the seminiferous tubules of the murine and rat spermatogenesis-related cell types were differentiated. Mosaicking improved the inspection potential by wide-angle views. Similarly, the microarchitecture of the epididymis and the vas deferens was successfully visualized in situ and on a cellular level by pCLE. In summary, pCLE allows for real-time identification of relevant microstructures responsible for spermatogenesis under ex vivo conditions. Additionally, pCLE enabled to localize vital spermatozoa in the testis thus opening up new ways to improve sperm retrieval rates during assisted reproduction. Both clinically relevant experiences hold promise to introduce this diagnostic method into a clinical study, and to investigate its potential as a clinical diagnostic procedure to expedite and improve the medical situation.


Probe-based confocal laser endomicroscopy (pCLE) Confocal laser scanning microscopy (CLSM) Male genital tract Optical imaging Diagnostic Andrology Urology 



We thank Mr. Myles Leavy for final proof reading.

Compliance with ethical standards

Ethical statement

This study was approved by the Ethics Committee of the University of Munich (project number 161-12). The use of the dead animals had been approved by the Institutional Animal Care and Use Committee (IACUC).

Conflict of interest

No competing financial interests exist.

Supplementary material

10103_2015_1828_MOESM1_ESM.mpg (1.1 mb)
Movie 1 Real-time view of a human testicular tubule mainly containining spermatogonia (staining: AC). (MPG 1132 kb)
10103_2015_1828_MOESM2_ESM.mp4 (434 kb)
Movie 2 Visualization of manipulations in human testicular tubules by pCLE. The contents of a tubulus contortus is pressed out which is recorded in real-time (staining: FITC). (MP4 434 kb)
10103_2015_1828_MOESM3_ESM.mp4 (2.3 mb)
Movie 3 In situ localization of spermatozoa in the human epididymis (see circular line, staining: FA). (MP4 2336 kb)


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Copyright information

© Springer-Verlag London 2015

Authors and Affiliations

  • Matthias Trottmann
    • 1
  • Ronald Sroka
    • 2
  • Herbert Stepp
    • 2
  • Bernhard Liedl
    • 3
  • Armin J. Becker
    • 1
  • Christian G. Stief
    • 1
  • Sabine Kölle
    • 1
    • 4
  1. 1.Department of Urology, Klinikum GrosshadernUniversity of MunichMunichGermany
  2. 2.LIFE Centre, Klinikum GrosshadernUniversity of MunichMunichGermany
  3. 3.Department of Urogenital SurgeryClinics for Surgery Munich-BogenhausenMunichGermany
  4. 4.Health Sciences Centre, UCD School of Medicine & Medical ScienceUniversity College DublinDublin 4Ireland

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