The role of ultrasound in assessment of male fertility.

Ultrasonography (US) is a widely used and well tolerated imaging modality for evaluation of pathologic conditions of the testes. Recent technical advances of US applications and post processing developments have enabled new aspects in the structural and functional analysis of testicular tissue and therefore male fertility. This review covers the most relevant approaches due to recent technical advances. Testicular volume measured by B-mode US correlated significantly with testicular function. Increased resistive index (RI) and pulsatility index (PI) of capsular branches of testicular arteries on unenhanced color Doppler US examination may be an indicator of impaired testicular microcirculation in patients with clinical varicocele. FSH was inversely correlated with testicular volume and directly correlated with testicular vascularization, suggesting that ultrasonographic and color Doppler scanning of the testes may be used, if a sperm count is not available, to indirectly assess the gonadal function. Perfusion mapping, performed with the use of color Doppler ultrasound, has shown for the first time that in patients suffering from azoospermia, sperm quality and quantity depend on tissue perfusion within the testicle. Testicular arterial blood flow was found to be significantly decreased in men with varicocele. This may be a reflection of the impaired microcirculation. Following decreased testicular arterial blood flow, impaired spermatogenesis may result from defective energy metabolism in the microcirculatory bed. Contrast-enhanced ultrasound (CEUS) imaging is potentially applicable to the investigation of vascular disorders of the testis. Pulse inversion (PI) US data can correctly determine relative testicular perfusion based on nonlinear curve fitting of the US backscatter intensity as a function of time and spectral analysis of the intensity time trace. PI imaging, compared with conventional Doppler US methods, provides superior assessment of perfusion in the setting of acute testicular ischemia. New contrast-enhanced US techniques like microvessel imaging (proposed by Philips) and CPS (proposed by Siemens-Acuson) allow for a better determination of tissue perfusion based on time intensity curves and an illustration of vessel distribution inside the testis. First results show a lower vessel density in atrophic testes and a difference in contrast dynamics in testes with impaired function. Real-time elastography, a method for illustration of tissue stiffness under real-time conditions, demonstrates different elasticity values dependent on testicular volume and function. Further studies will prove if these techniques can evolve into clinical practice.

[1]  N. Skakkebaek,et al.  Ultrasonic texture and volume of testicles in infertile men. , 1994, Human reproduction.

[2]  J. D. Neill,et al.  The Physiology of reproduction , 1988 .

[3]  Gregory T. Clement,et al.  Automated sonographic evaluation of testicular perfusion , 2006, Physics in medicine and biology.

[4]  Ronald H Gottlieb,et al.  Sonography of the scrotum. , 2003, Radiology.

[5]  Cihan Göktan,et al.  Effect of Varicocele on Testicular Artery Blood Flow in Men Color Doppler Investigation , 2003, Scandinavian journal of urology and nephrology.

[6]  E. Nieschlag,et al.  Objective measurement of testicular volume by ultrasonography: evaluation of the technique and comparison with orchidometer estimates. , 1989, International journal of andrology.

[7]  L. Kalish,et al.  Pulse-inversion US imaging of testicular ischemia: quantitative and qualitative analyses in a rabbit model. , 2006, Radiology.

[8]  K. Jeschke,et al.  Sonographie des Skrotalinhalts , 2006 .

[9]  S. Kitahara,et al.  Relationship of testicular volume to semen profiles and serum hormone concentrations in infertile Japanese males. , 1998, International journal of fertility and women's medicine.

[10]  R. Mieusset,et al.  Testicular size in infertile men: relationship to semen characteristics and hormonal blood levels. , 1989, British journal of urology.

[11]  A. Cockett,et al.  Significance of testicular size measurement in andrology: II. Correlation of testicular size with testicular function. , 1987, The Journal of urology.

[12]  R. Lerner,et al.  Color Doppler US in the evaluation of acute scrotal disease. , 1990, Radiology.

[13]  M. Siegel The acute scrotum. , 1997, Radiologic clinics of North America.

[14]  Y. Ogawa,et al.  Relationship between testicular volume and testicular function: comparison of the Prader orchidometric and ultrasonographic measurements in patients with infertility. , 2008, Asian journal of andrology.

[15]  Y. Ogawa,et al.  Testicular volume measurements using Prader orchidometer versus ultrasonography in patients with infertility. , 2007, Urology.

[16]  Ahmet Tuncay Turgut,et al.  Resistance and pulsatility index increase in capsular branches of testicular artery: Indicator of impaired testicular microcirculation in varicocele? , 2007, Journal of clinical ultrasound : JCU.

[17]  A. Atala,et al.  Testicular volume: comparison of orchidometer and US measurements in dogs. , 2002, Radiology.

[18]  Ralf Herwig,et al.  Tissue perfusion-controlled guided biopsies are essential for the outcome of testicular sperm extraction. , 2007, Fertility and sterility.

[19]  Y. Ogawa,et al.  Testicular volume measurement: comparison of ultrasonography, orchidometry, and water displacement. , 2007, Urology.

[20]  W. Middleton,et al.  Color Doppler ultrasound of the normal testis. , 1989, AJR. American journal of roentgenology.

[21]  M. Zacharias,et al.  Neue Techniken der Urosonographie , 2004, Der Urologe, Ausgabe A.

[22]  C. Foresta,et al.  Doppler ultrasound of the testis in azoospermic subjects as a parameter of testicular function. , 1998, Human reproduction.