Mysteries, facts, and fiction in varicocele pathophysiology and treatment

European Urology, Supplements

Volumn 13, Issue 4, 2014, Pages 89-99

  Sofikitis, Nikolaos ^a   Stavrou, Sotirios ^a   Skouros, Sotirios ^a   Dimitriadis, Fotios ^a   Tsounapi, Panagiota ^b   Takenaka, Atsushi ^b  

^a UNIVERSITY OF IOANNINA   (Greece)

^b TOTTORI UNIVERSITY   (Japan)

Author keywords

Azoospermia; Spermatozoa; Testis; Varicocele; Varicocelectomy

Indexed keywords

CADMIUM;

ADOLESCENCE; AZOOSPERMIA; CYTOPLASM; EXTRACELLULAR FLUID; HUMAN; HYPOTHALAMUS HYPOPHYSIS SYSTEM; HYPOXIA; LAPAROSCOPIC SURGERY; MALE FERTILITY; MALE GENITAL SYSTEM; META ANALYSIS (TOPIC); METABOLIC DISORDER; MICROSURGERY; NONHUMAN; OXIDATIVE STRESS; PATHOPHYSIOLOGY; REVIEW; SCROTUM; SEMEN ANALYSIS; SPERM QUALITY; SPERMATIC VEIN; TEMPERATURE; TESTIS; TREATMENT INDICATION; VARICOCELE; VARICOCELECTOMY;

EID: 85027958052     PISSN: 15699056     EISSN: 18781500     Source Type: Journal    
DOI: 10.1016/j.eursup.2014.07.002     Document Type: Review

References (126)

1. Fretz P.C., Sandlow J.I. Varicocele: current concepts in pathophysiology, diagnosis, and treatment. Urol Clin North Am 2002, 29:921-937.
2. Clarke B.G. Incidence of varicocele in normal men and among men of different ages. JAMA 1966, 198:1121-1122.
3. Greenberg S.H., Lipshultz L.I., Wein A.J. Experience with 425 subfertile male patients. J Urol 1978, 119:507-510.
4. Gorelick J.I., Goldstein M. Loss of fertility in men with varicocele. Fertil Steril 1993, 59:613-616.
5. The influence of varicocele on parameters of fertility in a large group of men presenting to infertility clinics. World Health Organization. Fertil Steril 1992, 57:1289-1293.
6. Sofikitis N., Miyagawa I. Experimental models for the study of varicocele: a selected review. Jpn J Fertil Steril 1993, 38:168-177.
7. Braedel H.U., Steffens J., Zeigler M., Polsky M.S., Platt M.L. A possible ontogenic etiology for idiopathic left varicocele. J Urol 1994, 151:62-66.
8. Braedel H.U., Steffens J., Ziegler M., Polsky M.S. Observations on the formation of the secondary venous system of the abdominal cavity with special reference to idiopathic left-sided varicocele [in German]. Rofo 1991, 155:11-19.
9. Sofikitis N., Dritsas K., Miyagawa I., Koutselinis A. Anatomical characteristics of the left testicular venous system in man. Arch Androl 1993, 30:79-85.
10. Comhaire F., Vermeulen A. Varicocele sterility: cortisol and catecholamines. Fertil Steril 1974, 25:88-95.
11. Naughton C.K., Nangia A.K., Agarwal A. Pathophysiology of varicoceles in male infertility. Hum Reprod Update 2001, 7:473-481.
12. Pasqualotto F.F., Sharma R.K., Nelson D.R., Thomas A.J., Agarwal A. Relationship between oxidative stress, semen characteristics, and clinical diagnosis in men undergoing infertility investigation. Fertil Steril 2000, 73:459-464.
13. Segenreich E., Israilov S., Shmuele J., Niv E., Baniel J., Livne P. Evaluation of the relationship between semen parameters, pregnancy rate of wives of infertile men with varicocele, and gonadotropin-releasing hormone test before and after varicocelectomy. Urology 1998, 52:853-857.
14. Su L.M., Goldstein M., Schlegel P.N. The effect of varicocelectomy on serum testosterone levels in infertile men with varicoceles. J Urol 1995, 154:1752-1755.
15. Marmar J.L. The pathophysiology of varicoceles in the light of current molecular and genetic information. Hum Reprod Update 2001, 7:461-472.
16. Pasqualotto F.F., Lucon A.M., Hallak J., Góes P.M., Saldanha L.B., Arap S. Induction of spermatogenesis in azoospermic men after varicocele repair. Hum Reprod 2003, 18:108-112.
17. Sharma R.K., Pasqualotto F.F., Nelson D.R., Thomas A.J., Agarwal A. The reactive oxygen species-total antioxidant capacity score is a new measure of oxidative stress to predict male infertility. Hum Reprod 1999, 14:2801-2807.
18. Ali J.I., Weaver D.J., Weinstein S.H., Grimes E.M. Scrotal temperature and semen quality in men with and without varicocele. Arch Androl 1990, 24:215-219.
19. Hsiung R., Nieva H., Clavert A. Scrotal hyperthermia and varicocele. Adv Exp Med Biol 1991, 286:241-244.
20. Lerchl A., Keck C., Spiteri-Grech J., Nieschlag E. Diurnal variations in scrotal temperature of normal men and patients with varicocele before and after treatment. Int J Androl 1993, 16:195-200.
21. Khera M., Lipshultz L.I. Evolving approach to the varicocele. Urol Clin North Am 2008, 35:183-189.
22. Rajfer J., Turner T.T., Rivera F., Howards S.S., Sikka S.C. Inhibition of testicular testosterone biosynthesis following experimental varicocele in rats. Biol Reprod 1987, 36:933-937.
23. Wright E.J., Young G.P., Goldstein M. Reduction in testicular temperature after varicocelectomy in infertile men. Urology 1997, 50:257-259.
24. Saypol D.C., Howards S.S., Turner T.T., Miller E.D. Influence of surgically induced varicocele on testicular blood flow, temperature, and histology in adult rats and dogs. J Clin Invest 1981, 68:39-45.
25. Sofikitis N., Takahashi C., Kadowaki H., et al. Surgical repair versus medical treatment of varicocele in the rat: pharmacological manipulation of the varicocelized testicle. Eur Urol 1992, 22:44-52.
26. Sofikitis N., Miyagawa I. Effects of surgical repair of experimental left varicocele on testicular temperature, spermatogenesis, sperm maturation, endocrine function, and fertility in rabbits. Arch Androl 1992, 29:163-175.
27. Sofikitis N.V., Miyagawa I., Incze P., Andrighetti S. Detrimental effect of left varicocele on the reproductive capacity of the early haploid male gamete. J Urol 1996, 156:267-270.
28. Harrison R.M., Smith S.D., Roberts J.A. Testicular temperatures measured by thermistor probe and contact thermography. Fertil Steril 1990, 54:173-174.
29. Hurt G.S., Howards S.S., Turner T.T. Repair of experimental varicoceles in the rat. Long-term effects on testicular blood flow and temperature and cauda epididymidal sperm concentration and motility. J Androl 1986, 7:271-276.
30. Schlegel P.N., Goldstein M. Alternate indications for varicocele repair: non-obstructive azoospermia, pain, androgen deficiency and progressive testicular dysfunction. Fertil Steril 2011, 96:1288-1293.
31. Swerdloff R.S., Walsh P.C. Pituitary and gonadal hormones in patients with varicocele. Fertil Steril 1975, 26:1006-1012.
32. Hudson R.W., Perez-Marrero R.A., Crawford V.A., McKay D.E. Hormonal parameters of men with varicoceles before and after varicocelectomy. Fertil Steril 1985, 43:905-910.
33. Javert C., Clark R. Combined operation for varicocele and inguinal hernia: preliminary report. Surg Gyn Obst 1944, 79:644-650.
34. Mazo E.B., Koriakin M.V., Evseev L.P., Akopian A.S. The role of the functional interrelation of the adrenals and testes in the pathogenesis of sterility in patients with left-sided varicocele [in Russian]. Urol Nefrol (Mosk) 1990, 50-58.
35. Cohen M.S., Plaine L., Brown J.S. The role of internal spermatic vein plasma catecholamine determinations in subfertile men with varicoceles. Fertil Steril 1975, 26:1243-1249.
36. Ito H., Fuse H., Minagawa H., Kawamura K., Murakami M., Shimazaki J. Internal spermatic vein prostaglandins in varicocele patients. Fertil Steril 1982, 37:218-222.
37. Lindholmer C.L., Thulin L., Eliasson R. Concentrations of cortisol and renin in the internal spermatic vein of men with varicocele. Andrologie 1973, 5:21-22.
38. Sofikitis N., Miyagawa I. Left adrenalectomy in varicocelized rats does not inhibit the development of varicocele-related physiologic alterations. Int J Fertil Menopausal Stud 1993, 38:250-255.
39. Kilinc F., Kayaselcuk F., Aygun C., Guvel S., Egilmez T., Ozkardes H. Experimental varicocele induces hypoxia inducible factor-1alpha, vascular endothelial growth factor expression and angiogenesis in the rat testis. J Urol 2004, 172:1188-1191.
40. Hsu H.S., Chang L.S., Chen M.T., Wei Y.H. Decreased blood flow and defective energy metabolism in the varicocele-bearing testicles of rats. Eur Urol 1994, 25:71-75.
41. Harrison R.M., Lewis R.W., Roberts J.A. Pathophysiology of varicocele in nonhuman primates: long-term seminal and testicular changes. Fertil Steril 1986, 46:500-510.
42. Turner T.T., Lopez T.J. Testicular blood flow in peripubertal and older rats with unilateral experimental varicocele and investigation into the mechanism of the bilateral response to the unilateral lesion. J Urol 1990, 144:1018-1021.
43. Turner T.T. The study of varicocele through the use of animal models. Hum Reprod Update 2001, 7:78-84.
44. Salama N., Bergh A., Damber J.E. The changes in testicular vascular permeability during progression of the experimental varicocele. Eur Urol 2003, 43:84-91.
45. Sweeney T.E., Rozum J.S., Gore R.W. Alteration of testicular microvascular pressures during venous pressure elevation. Am J Physiol 1995, 269:H37-H45.
46. Wang H., Sun Y., Wang L., et al. Hypoxia-induced apoptosis in the bilateral testes of rats with left-sided varicocele: a new way to think about the varicocele. J Androl 2010, 31:299-305.
47. Girgis S.M., Abd el-Rahman Y., Awad H., et al. Lactate and pyruvate levels in the testicular vein of subfertile males with varicocele as a test for the theory of underlying hypoxia. Andrologia 1981, 13:16-19.
48. Sofikitis N., Miyagawa I. Bilateral effect of unilateral varicocele on testicular metabolism in the rabbit. Int J Fertil Menopausal Stud 1994, 39:239-247.
49. Benoff S.H., Millan C., Hurley I.R., Napolitano B., Marmar J.L. Bilateral increased apoptosis and bilateral accumulation of cadmium in infertile men with left varicocele. Hum Reprod 2004, 19:616-627.
50. Benoff S., Goodwin L.O., Millan C., Hurley I.R., Pergolizzi R.G., Marmar J.L. Deletions in L-type calcium channel alpha1 subunit testicular transcripts correlate with testicular cadmium and apoptosis in infertile men with varicoceles. Fertil Steril 2005, 83:622-634.
51. Hurt G.S., Howards S.S., Turner T.T. The effects of unilateral, experimental varicocele are not mediated through the ipsilateral testis. J Androl 1987, 8:403-408.
52. Green K.F., Turner T.T., Howards S.S. Effects of varicocele after unilateral orchiectomy and sympathectomy. J Urol 1985, 134:378-383.
53. Sofikitis N., Takahashi C., Nakamura I., Hirakawa S., Miyagawa I. Surgical repair of secondary right varicocele in rats with primary left varicocele: effects on fertility, testicular temperature, spermatogenesis, and sperm maturation. Arch Androl 1992, 28:43-52.
54. Ozturk H., Tander B., Aydin A., Okumus Z., Cetinkursun S. The effects of chemical sympathectomy on testicular injury in varicocele. BJU Int 2001, 87:232-234.
55. Hendin B.N., Kolettis P.N., Sharma R.K., Thomas A.J., Agarwal A. Varicocele is associated with elevated spermatozoal reactive oxygen species production and diminished seminal plasma antioxidant capacity. J Urol 1999, 161:1831-1834.
56. Pasqualotto F.F., Sundaram A., Sharma R.K., Borges E., Pasqualotto E.B., Agarwal A. Semen quality and oxidative stress scores in fertile and infertile patients with varicocele. Fertil Steril 2008, 89:602-607.
57. Nallella K.P., Allamaneni S.S., Pasqualotto F.F., Sharma R.K., Thomas A.J., Agarwal A. Relationship of interleukin-6 with semen characteristics and oxidative stress in patients with varicocele. Urology 2004, 64:1010-1013.
58. Agarwal A., Sharma R.K., Desai N.R., Prabakaran S., Tavares A., Sabanegh E. Role of oxidative stress in pathogenesis of varicocele and infertility. Urology 2009, 73:461-469.
59. Yesilli C., Mungan G., Seçkiner I., et al. Effect of varicocelectomy on sperm creatine kinase, HspA2 chaperone protein (creatine kinase-M type), LDH, LDH-X, and lipid peroxidation product levels in infertile men with varicocele. Urology 2005, 66:610-615.
60. Agarwal A., Prabakaran S., Allamaneni S.S. Relationship between oxidative stress, varicocele and infertility: a meta-analysis. Reprod Biomed Online 2006, 12:630-633.
61. Aitken R.J., Baker M.A. Causes and consequences of apoptosis in spermatozoa; contributions to infertility and impacts on development. Int J Dev Biol 2013, 57:265-272.
62. Goodpasture J.C., Zavos P.M., Zaneveld L.J. Relationship of human sperm acrosin and proacrosin to semen parameters. II. Correlations. J Androl 1987, 8:267-271.
63. Sofikitis N., Miyagawa I., Zavos P.M., et al. Acrosin profiles of human spermatozoa recovered from the new Sperm Prep II filtration column. Tohoku J Exp Med 1992, 166:451-457.
64. El Mulla K.F., Köhn F.M., El Beheiry A.H., Schill W.B. The effect of smoking and varicocele on human sperm acrosin activity and acrosome reaction. Hum Reprod 1995, 10:3190-3194.
65. Saleh R.A., Agarwal A., Sharma R.K., Said T.M., Sikka S.C., Thomas A.J. Evaluation of nuclear DNA damage in spermatozoa from infertile men with varicocele. Fertil Steril 2003, 80:1431-1436.
66. Blumer C.G., Fariello R.M., Restelli A.E., Spaine D.M., Bertolla R.P., Cedenho A.P. Sperm nuclear DNA fragmentation and mitochondrial activity in men with varicocele. Fertil Steril 2008, 90:1716-1722.
67. Smit M., Romijn J.C., Wildhagen M.F., Veldhoven J.L., Weber R.F., Dohle G.R. Decreased sperm DNA fragmentation after surgical varicocelectomy is associated with increased pregnancy rate. J Urol 2010, 183:270-274.
68. Zini A., Defreitas G., Freeman M., Hechter S., Jarvi K. Varicocele is associated with abnormal retention of cytoplasmic droplets by human spermatozoa. Fertil Steril 2000, 74:461-464.
69. Zini A., O'Bryan M.K., Israel L., Schlegel P.N. Human sperm NADH and NADPH diaphorase cytochemistry: correlation with sperm motility. Urology 1998, 51:464-468.
70. Dimitriadis F., Giannakis D., Pardalidis N., et al. Effects of primary testicular damage on sperm DNA oxidative status and embryonic and foetal development. Andrologia 2009, 41:282-296.
71. Snydle F.E., Cameron D.F. Surgical induction of varicocele in the rabbit. J Urol 1983, 130:1005-1009.
72. Giagulli V.A., Carbone M.D. Varicocele correction for infertility: which patients to treat?. Int J Androl 2011, 34:236-241.
73. Baazeem A., Belzile E., Ciampi A., et al. Varicocele and male factor infertility treatment: a new meta-analysis and review of the role of varicocele repair. Eur Urol 2011, 60:796-808.
74. Grasso M., Lania C., Castelli M., Galli L., Franzoso F., Rigatti P. Low-grade left varicocele in patients over 30 years old:the effect of spermatic vein ligation on fertility. BJU Int 2000, 85:305-307.
75. Unal D., Yeni E., Verit A., Karatas O.F. Clomiphene citrate versus varicocelectomy in treatment of subclinical varicocele: a prospective randomized study. Int J Urol 2001, 8:227-230.
76. Yamamoto M., Hibi H., Hirata Y., Miyake K., Ishigaki T. Effect of varicocelectomy on sperm parameters and pregnancy rate in patients with subclinical varicocele: a randomized prospective controlled study. J Urol 1996, 155:1636-1638.
77. Breznik R., Vlaisavljevic V., Borko E. Treatment of varicocele and male fertility. Arch Androl 1993, 30:157-160.
78. Nilsson S., Edvinsson A., Nilsson B. Improvement of semen and pregnancy rate after ligation and division of the internal spermatic vein: fact or fiction?. Br J Urol 1979, 51:591-596.
79. Gat Y., Bachar G.N., Everaert K., Levinger U., Gornish M. Induction of spermatogenesis in azoospermic men after internal spermatic vein embolization for the treatment of varicocele. Hum Reprod 2005, 20:1013-1017.
80. Matthews G.J., Matthews E.D., Goldstein M. Induction of spermatogenesis and achievement of pregnancy after microsurgical varicocelectomy in men with azoospermia and severe oligoasthenospermia. Fertil Steril 1998, 70:71-75.
81. Giannakis D., Baltogiannis D., Tsoukanelis K., et al. Role of testicular tissue telomerase assay for the prediction of the presence of testicular spermatozoa in azoospermic men with varicoceles, pre- and post-varicocelectomy. Andrologia 2004, 36:111-122.
82. Kadioglu A., Tefekli A., Cayan S., Kandirali E., Erdemir F., Tellaloglu S. Microsurgical inguinal varicocele repair in azoospermic men. Urology 2001, 57:328-333.
83. Kim E.D., Leibman B.B., Grinblat D.M., Lipshultz L.I. Varicocele repair improves semen parameters in azoospermic men with spermatogenic failure. J Urol 1999, 162:737-740.
84. Kass E.J., Belman A.B. Reversal of testicular growth failure by varicocele ligation. J Urol 1987, 137:475-476.
85. Okuyama A., Fujisue H., Matsui T., et al. Preoperative parameters related to the improvement of semen characteristics after surgical repair of varicocele in subfertile men. Eur Urol 1988, 14:442-446.
86. Decastro G.J., Shabsigh A., Poon S.A., Laor L., Glassberg K.I. Adolescent varicocelectomy-is the potential for catch-up growth related to age and/or Tanner stage?. J Urol 2009, 181:322-327. discussion 327.
87. Cayan S., Shavakhabov S., Kadioglu A. Treatment of palpable varicocele in infertile men: a meta-analysis to define the best technique. J Androl 2009, 30:33-40.
88. Goldstein M. Surgical management of male infertility. Campbell-Walsh Urology 2012, 648-687. Elsevier Saunders, Philadelphia, PA. A.J. Wein, L. Kavoussi, A.C. Novick, A.W. Partin, C.A. Peters (Eds.).
89. Sayfan J., Adam Y.G., Soffer Y. A new entity in varicocele subfertility: the “cremasteric reflux.“. Fertil Steril 1980, 33:88-90.
90. Murray R.R., Mitchell S.E., Kadir S., et al. Comparison of recurrent varicocele anatomy following surgery and percutaneous balloon occlusion. J Urol 1986, 135:286-289.
91. Szabo R., Kessler R. Hydrocele following internal spermatic vein ligation: a retrospective study and review of the literature. J Urol 1984, 132:924-925.
92. Matsuda T., Horii Y., Yoshida O. Should the testicular artery be preserved at varicocelectomy?. J Urol 1993, 149:1357-1360.
93. Sofikitis N., Miyagawa I., Zavos P.M. Re: Should the testicular artery be preserved at varicocelectomy?. J Urol 1994, 151:1355.
94. Donovan J.F., Winfield H.N. Laparoscopic varix ligation. J Urol 1992, 147:77-81.
95. Enquist E., Stein B.S., Sigman M. Laparoscopic versus subinguinal varicocelectomy: a comparative study. Fertil Steril 1994, 61:1092-1096.
96. Hagood P.G., Mehan D.J., Worischeck J.H., Andrus C.H., Parra R.O. Laparoscopic varicocelectomy: preliminary report of a new technique. J Urol 1992, 147:73-76.
97. Hirsch I.H., Abdel-Meguid T.A., Gomella L.G. Postsurgical outcomes assessment following varicocele ligation: laparoscopic versus subinguinal approach. Urology 1998, 51:810-815.
98. Riccabona M., Oswald J., Koen M., Lusuardi L., Radmayr C., Bartsch G. Optimizing the operative treatment of boys with varicocele: sequential comparison of 4 techniques. J Urol 2003, 169:666-668.
99. Watanabe M., Nagai A., Kusumi N., Tsuboi H., Nasu Y., Kumon H. Minimal invasiveness and effectivity of subinguinal microscopic varicocelectomy: a comparative study with retroperitoneal high and laparoscopic approaches. Int J Urol 2005, 12:892-898.
100. Glassberg K.I., Poon S.A., Gjertson C.K., DeCastro G.J., Misseri R. Laparoscopic lymphatic sparing varicocelectomy in adolescents. J Urol 2008, 180:326-330. discussion 330-1.
101. Hopps C.V., Lemer M.L., Schlegel P.N., Goldstein M. Intraoperative varicocele anatomy: a microscopic study of the inguinal versus subinguinal approach. J Urol 2003, 170:2366-2370.
102. Cayan S., Kadioglu T.C., Tefekli A., Kadioglu A., Tellaloglu S. Comparison of results and complications of high ligation surgery and microsurgical high inguinal varicocelectomy in the treatment of varicocele. Urology 2000, 55:750-754.
103. Goldstein M., Gilbert B.R., Dicker A.P., Dwosh J., Gnecco C. Microsurgical inguinal varicocelectomy with delivery of the testis: an artery and lymphatic sparing technique. J Urol 1992, 148:1808-1811.
104. Marmar J.L., Kim Y. Subinguinal microsurgical varicocelectomy: a technical critique and statistical analysis of semen and pregnancy data. J Urol 1994, 152:1127-1132.
105. Al-Kandari A.M., Shabaan H., Ibrahim H.M., Elshebiny Y.H., Shokeir A.A. Comparison of outcomes of different varicocelectomy techniques: open inguinal, laparoscopic, and subinguinal microscopic varicocelectomy: a randomized clinical trial. Urology 2007, 69:417-420.
106. Al-Said S., Al-Naimi A., Al-Ansari A., et al. Varicocelectomy for male infertility: a comparative study of open, laparoscopic and microsurgical approaches. J Urol 2008, 180:266-270.
107. Boman J.M., Libman J., Zini A. Microsurgical varicocelectomy for isolated asthenospermia. J Urol 2008, 180:2129-2132.
108. Lima S.S., Castro M.P., Costa O.F. A new method for the treatment of varicocele. Andrologia 1978, 10:103-106.
109. Weissbach L., Thelen M., Adolphs H.D. Treatment of idiopathic varicoceles by transfemoral testicular vein occlusion. J Urol 1981, 126:354-356.
110. Morag B., Rubinstein Z.J., Goldwasser B., Yerushalmi A., Lunnenfeld B. Percutaneous venography and occlusion in the management of spermatic varicoceles. AJR Am J Roentgenol 1984, 143:635-640.
111. Sivanathan C., Abernethy L.J. Retrograde embolisation of varicocele in the paediatric age group: a review of 10 years' practice. Ann R Coll Surg Engl 2003, 85:50-51.
112. White R.I., Kaufman S.L., Barth K.H., Kadir S., Smyth J.W., Walsh P.C. Occlusion of varicoceles wih detachable balloons. Radiology 1981, 139:327-334.
113. Matthews R.D., Roberts J., Walker W.A., Sands J.P. Migration of intravascular balloon after percutaneous embolotherapy of varicocele. Urology 1992, 39:373-375.
114. Ficarra V., Sarti A., Novara G., Artibani W. Antegrade scrotal sclerotherapy and varicocele. Asian J Androl 2002, 4:221-224.
115. Minucci S., Mazzoni G., Gallina A., Gentile V., Pavone P. Evolution in varicocele sclerosing treatment: the ante/retrograde (A/R) approach. Arch Ital Urol Androl 2004, 76:29-33.
116. Tauber R., Johnsen N. Antegrade scrotal sclerotherapy for the treatment of varicocele: technique and late results. J Urol 1994, 151:386-390.
117. Nieschlag E., Hertle L., Fischedick A., Abshagen K., Behre H.M. Update on treatment of varicocele: counselling as effective as occlusion of the vena spermatica. Hum Reprod 1998, 13:2147-2150.
118. Madgar I., Weissenberg R., Lunenfeld B., Karasik A., Goldwasser B. Controlled trial of high spermatic vein ligation for varicocele in infertile men. Fertil Steril 1995, 63:120-124.
119. Abdel-Meguid T.A., Al-Sayyad A., Tayib A., Farsi H.M. Does varicocele repair improve male infertility? An evidence-based perspective from a randomized, controlled trial. Eur Urol 2011, 59:455-461.
120. Pasqualotto F.F., Braga D.P., Figueira R.C., Setti A.S., Iaconelli A., Borges E. Varicocelectomy does not impact pregnancy outcomes following intracytoplasmic sperm injection procedures. J Androl 2012, 33:239-243.
121. Gokce M.I., Gülpinar O., Süer E., Mermerkaya M., Aydos K., Yaman O. Effect of performing varicocelectomy before intracytoplasmic sperm injection on clinical outcomes in non-azoospermic males. Int Urol Nephrol 2013, 45:367-372.
122. Evers J.L., Collins J.A. Assessment of efficacy of varicocele repair for male subfertility: a systematic review. Lancet 2003, 361:1849-1852.
123. Kroese A.C., de Lange N.M., Collins J., Evers J.L. Surgery or embolization for varicoceles in subfertile men. Cochrane Database Syst Rev 2012, 10:CD000479.
124. Kroese A.C., de Lange N.M., Collins J.A., Evers J.L. Varicocele surgery, new evidence. Hum Reprod Update 2013, 19:317.
125. Sofikitis N.V., Miyagawa I., Zavos P.M., Toda T., Iino A., Terakawa N. Confocal scanning laser microscopy of morphometric human sperm parameters: correlation with acrosin profiles and fertilizing capacity. Fertil Steril 1994, 62:376-386.
126. Toda T., Sofikitis N., Miyagawa I., et al. The importance of the hypoosmotic swelling test and acrosin activity assay for identifying subpopulations of idiopathic infertile men. Arch Androl 1992, 29:219-224.