Puberty: Physiology and Abnormalities, 1st ed. 2016

15. Adolescent Varicocele

Ahmad Majzoub  and Edmund SabaneghJr. 

(1)

Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, Cleveland, OH 44195, USA

Ahmad Majzoub

Email: majzoua@ccf.org

Edmund SabaneghJr. (Corresponding author)

Email: sabanee@ccf.org

Keywords

Adolescent varicoceleSemen analysisInfertilityMicrosurgical varicocelectomyLaparoscopic varicocelectomyConventional varicocelectomyTesticular hyperthermiaTesticular volume

Introduction

A varicocele is the abnormal dilatation of pampiniform plexus of veins in the scrotum [1]. Adolescent varicocele has gained a lot of interest principally because the condition starts around childhood or adolescence, progresses with age, and may affect testicular growth, rendering it the most common cause of adult male infertility .

History of Varicocele

For almost 2000 years, the term varicocele has been linked to testicular ailments. In his treatise “De Medicina,” Celsus (25 BC) was the first to associate varicocele to testicular atrophy [2]. With the beginning of the seventeenth century, many believed in the presence of a solid connection between varicocele and infertility [3]. However, caution from the liberal performance of surgery started after a tragic incidence in 1832, when J. Delpech, a well-known professor of surgery, was murdered by a man who suffered from testicular atrophy as a consequence of bilateral varicocele surgery [4]. Since then, awareness to such risk factors triggered a search for more conservative approach to varicocele management through the use of suspensory garments, cold showers, and lifestyle modifications such as moderation in sexual habits [4].

In spite of major surgical advancements in the early 1900s, caution remained a prevailing view to varicocele surgery. Conservative measures were often practiced by many physicians who believed in their success or were simply not convinced with surgery [4]. Interest in surgery re-immerged only after the introduction of inguinal and retroperitoneal ligature procedures and several reports followed demonstrating effect of varicocele surgery on fertility. In 1952, Tulloch was the first to report appearance of sperm after performing bilateral varicocelectomy to a patient with azoospermia [5]. Many other uncontrolled trials also revealed an improvement in semen parameters after surgery [6] and generated additional interest in surgical technique modification. The introduction of optical magnification and ultrasound probes in 1983 [7] had positive impact on surgical outcome. Different approaches were also explored, such as the subinguinal approach in 1985 [8] and laparoscopic approach in 1992 [9]. Today varicocelectomy is by far the most commonly performed operation for the treatment of male infertility . However, proper patient selection is still the most important factor to maximize patient benefit.

Epidemiology

The prevalence of varicocele varies greatly and is estimated to be in the range of 10–20 % of the general male population [210]. This discrepancy is due to differe nces in origin and nature of the studied population and more importantly because the condition is often subjectively diagnosed. The condition appears at puberty but can also be present in prepubertal boys [11], as young as 10 years of age [12]. In a study of 6200 boys, Kumanov and colleagues detected varicocele in about 8 % of boys between 10 and 19 years of age [13]. The prevalence was also found to increase with age [14], at a rate of 10 % each decade, afflicting 75 % of men by their eighth decade of life [15]. Varicoceles are much more common in the subfertile population affecting 35 and 80 % of men with primary and secondary infertility, respectively [16]. These reasons mark varicocele as a progressive disease with deleterious effects on testicular function [1417].

Few studies revealed an inverse relationship between varicocele and body mass index, denoting a higher prevalence of disease among lean men although this may relate to more ease of diagnosis in the lean population [1819]. First-degree relatives are also more commonly affected, suggesting a genetic pattern of inheritance [17].

Etiology

An understanding of the anatomy of the vascular supply of the testes is essential before explaining varicocele etiology. The anatomical position of the testis and its unique vascular supply are crucial for its optimal physiology and contribution to men’s reproductive health. A triple arterial supply to the testes exists. The first is the testicular artery (or internal spermatic artery) that originates from the aorta. The second is the cremasteric artery (or external spermatic artery), which originates from the inferior epigastric artery, a branch of the external iliac artery. The third is the deferential (vasal) artery, which originates from the superior vesical artery, a branch of the internal iliac artery.

Venous drainage, on the other hand, is more complicated, with many individual routes. A network of venous communications called the pampiniform plexus exists above the testes and drains through the testicular vein, pudendal veins, and vasal veins [20]. In the inguinal canal, the pampiniform plexus of veins travels in close proximity to the testicular arteries allowing for countercurrent heat exchange, which is thought to be the method by which the arterial blood going to the testis is cooled to temperatures as low as 33 °C [21]. The left testicular vein drains into the left renal vein, while the right testicular vein drains directly into the inferior vena cava. Variations do exist; the left testicular vein can rarely drain to the inferior vena cava or communicates with it before entering the renal vein [22].

Several theories have been proposed in the etiology of varicocele. Idiopathic varicocele is a term given when varicocele is thought to result from incompetent or absent unidirectional valves within the gonadal veins. This concept remains debatable. Despite the significant association that some researchers found between varicocele and valvular incompetence in the saphenofemoral junction [2324], others have demonstrated the presence of varicocele in patients with competent venous system [2526] or even failed to identify the presence of such valves [2728].

The predilection of varicocele on the left side triggered an assumption that anatomical differences may be contributing to varicocele etiology. These differences, which are thought to result in higher left venous hydrostatic pressure, include (1) longer left testicular vein by around 8–10 cm than its counterpart [29], (2) perpendicular angle of entry of the left testicular vein into the left renal vein in comparison to a more acute angle of entry of the right vein into the IVC, (3) and presence of a “nutcracker effect” resulting in a higher left renal vein pressure as it is compressed between the superior mesenteric artery and the aorta [30]. Gat and colleagues were able to validate the presence of high left spermatic vein hydrostatic pressure [31].

Animal studies have hypothesized that adolescent varicocele could result from increased arterial blood flow to the testis at puberty. The amount of flow exceeds the venous capacity and results in dilatation and engorgement of the pampiniform plexus of veins [32]. The likelihood of this information should be confirmed with human studies before adopting such a hypothesis.

Varicocele has been associated with several urological and non-urological medical conditions both in adolescents and adults. Examples include premature ejaculation [33], prostatitis [33], ankylosing spondylitis [34], and chronic obstructive pulmonary disease [35]. On a higher level, varicocele was associated with specific somatometric parameters in adolescents. It had a direct relationship with patient’s age, height, and penile length and an inverse relationship with testicular volume , BMI, and pubic hair distribution [36]. Furthermore, Kumanov and colleagues detected a possible link between varicocele and iris pigmentation [37].

Secondary varicocele is a term given when the condition occurs as a result of venous compression from retroperitoneal tumors such as sarcomas, lymphomas, or renal tumors. It should be suspected when encountering varicocele on the right side, relatively acute onset, or when the distention does not reside when the patient lies on his back.

Pathophysiology

Several pathophysiologic mechanisms have been proposed to help explain the deleterious effects of varicocele on testicular function. It is likely that not just a single mechanism is responsible, but rather a combination that ultimately results in testicular dysfunction.

Hyperthermia

Increased intratesticular temperature secondary to varicocele is the most commonly studied pathophysiology. It has long been observed that minor changes in testicular temperature can affect spermatogenesis [38]. The reason for this is that many of the enzymes responsible for DNA synthesis in the testis are temperature dependent [39], mainly favoring temperatures lower than body temperature. The anatomic position of the testis in the scrotal sac together with the countercurrent cooling mechanism provided by the pampiniform plexus of veins is responsible for testicular temperature regulation [40]. In a varicocele, the resulting blood stasis disrupts the countercurrent cooling effect causing testicular temperature elevation and defective spermatogenesis [41]. Scrotal skin temperature measurement, which reliably reflects testicular temperature [42], was assessed in few studies. In a comparative study, Wright and colleagues confirmed the presence of higher scrotal skin temperature in patients with varicocele with successful reduction to near-normal levels after varicocele ligation [43]. Moreover, scrotal temperature elevation was found to be a more accurate reflection of testicular dysfunction than the grade of varicocele [44].

Adrenal Reflux

Reflux of blood down the testicular vein has been demonstrated in patients with varicocele [45]. This triggered the hypothesis that exposure of the testis to adrenal and renal metabolites could be the reason for defective spermatogenesis. Chemicals such as adrenomedullin, catecholamines, cortisol, prostaglandins E and F, and serotonin were suggested. Animal studies on this issue showed conflicting results. Although Camoglio et al. [46] demonstrated worse testicular pathology in varicocele-induced rats with intact adrenal gland than in rats that had adrenalectomy, other studies failed to document the presence of such metabolites at the testicular levels [47].

Endocrine Imbalance

Puberty and testicular development are regulated by the hypothalamic-pituitary gonadal axis. Several endocrine disturbances were found to be associated with varicocele, most notable of which are low intratesticular levels of testosterone [4849]. Intratesticular testosterone is the most important regulator of spermatogenesis [50]. The exact cause of this finding may be secondary to suboptimal function of Leydig cells often observed with varicocele [48] or from a pattern similar to hypergonadotropic hypogonadism [51]. An abnormal response to gonadotropin-releasing hormone (GnRH) is found with elevated levels of LH resulting in Leydig cell hyperplasia [52]. Sertoli cell dysfunction has also been observed in association with supranormal levels of FSH. These endocrine imbalances were found in all varicocele patients irrespective of their fertility status. Varicocelectomy was associated with normalization of FSH, LH, and intratesticular testosterone levels [4953].

Disturbance of Paracrine Regulation

In addition to optimal levels of intratesticular testosterone, spermatogenesis is regulated by complex interactions and signals at the cellular level. Germ cell apoptosis is under the control of Sertoli cells through utilization of the Fas system. The Fas is a transmembrane receptor protein expressed on germ cells and is under the control of proapoptotic ligand Fas (FasL) and antiapoptotic soluble Fas (sFas), both secreted by Sertoli cells [54]. As a result of Sertoli cell dysfunction, patients with varicoceles were found to have higher levels of seminal FasL and lower levels of seminal sFas [5556]. Inhibin is another substance produced by Sertoli cells. It has a negative feedback control on pituitary FSH secretion. Additionally it works in a paracrine manner stimulating Leydig cells to produce testosterone. Again adolescents with varicocele were found to have subnormal levels of inhibin B that positively correlated with testicular volume [57].

Free radicals are other forms of paracrine disturbances as they are produced and act locally. They include a wide variety of compounds that are generally divided into reactive oxygen or nitrogen species [58]. Nitrous oxide (NO) is perh aps the most commonly studied substance in varicocele. It was detected in high quantities within the dilated spermatic veins of adolescents with varicocele [59]. Moreover, a direct relation exists between the level of seminal NO and degree of varicocele, i.e., the higher the grade of varicocele, the greater the NO level [60]. NO is synthesized by nitric oxide synthase (NOS) commonly present in neutrophils and macrophages. However under stressful conditions, spermatozoa are also capable of producing NO [61]. Studies on adolescents with varicocele discovered overexpression of NOS in their Leydig cells [62]. Under normal physiologic concentrations, NO produced by Leydig cells diffuses across cellular membranes and stimulates testicular function. However, its overproduction could initiate different pathological consequences. First, it causes vasodilatation of blood vessels resulting in blood stasis [63]; second, it causes prolonged relaxation of peritubular myofibroblasts ultimately affecting the peristaltic activity necessary for sperm transport [63]; third, high levels of NO can inhibit steroidogenesis and reduce testosterone production by Leydig cells [64]; lastly, it could alter Sertoli cell junctions that are fundamental in regulating cellular adhesion, proliferation, migration, and differentiation [65].

Spermatozoa are extremely sensitive to oxidative stress as they lack the necessary enzyme repair systems [66]. As a result, free radicals affect spermatozoa in three main ways: membrane lipid peroxidation, DNA damage, and induction of apoptosis [67]. The spermatozoan membrane is rich in polyunsaturated fatty acids that are susceptible to lipid peroxidation. This process results in loss of intracellular adenosine triphosphate (ATP) causing reduction in sperm viability and motility and alteration of its morphology [68]. Free radicals directly attack the purine and pyrimidine bases destabilizing the DNA molecule and causing anomalies such as point mutations, polymorphisms, deletions, translocations, and even double-stranded breaks [69]. Finally, depending on the degree of the insult, apoptosis will be triggered through the Fas system described above.

Presentation and Diagnosis

Varicocele in the adolescent may present in a variety of ways. Most commonly, it is asymptomatic and often diagnosed during genital examination performed as part of routine sports or school checkups. Sometimes the adolescent notices a scrotal swelling or complains of a dull, bothersome discomfort in the scrotal region, especially after exercise or prolonged standing.

Clinical examination should start while the adolescent is in the standing position preferably in a warm room. The scrotum is inspected for any obvious venous distention around the sperma tic cord, which, if seen, denotes the presence of grade 3 varicocele (Fig. 15.1). The scrotum, testes, and cord structures are then gently palpated. A palpable varicocele is described as a feeling of a bag of worms or a squishy tube, which, if felt, indicates the presence of grade 2 varicocele. If nothing is palpable, except for a filling sensation felt between the fingers of the examiner as the patient performs the Valsalva maneuver, a grade 1 varicocele is present.

A334826_1_En_15_Fig1_HTML.jpg

Fig. 15.1

Grade III varicocele in an adolescent (Reprinted from Esteves SC, Miyaoka R, Agarwal A. An update on the clinical assessment of the infertile male. Clinics. 2011; 66 (4): 691–700. With permission from CLINICS)

After examining the patient in the standing position, the patient should be examined supine. Idiopathic varicocele should disappear in the supine position. Persistence of the swelling in supine position, especially on the right side, should raise suspicion for the possibility of secondary causes of varicocele. Retroperitoneal tumors, kidney tumors, and lymphadenopathy are possible causes for secondary varicocele. Additionally, cord thickening due to varicocele should resolve in supine position, whereas a cord lipoma can be suspected if thickening of the cord persists.

Testicular size measurement is crucial to determine whether the varicocele is adversely affecting testicular growth. On palpation one can most effectively gauge whether the right and left sides are grossly symmetric. A prepubertal testis should have a volume of 1–3 mL. A size of >3 mL indicates the initiation of puberty, and this enlargement generally begins before any sign of pubic hair. Because of extensive individual variation in normal growth and development, testicular size is correlated with Tanner stage, growth velocity, and bone age rather than chronological age.

Testicular volume and consistency are an important component of varicocele assessment in the adolescent. Dimensions of the testis can be assessed with caliper measurements in the three dimensions. More commonly, testicular volume can be clinically assessed using a variety of devices including the Prader orchidometer [70], a string of ovoid-shaped beads of increasing sizes, and the Rochester (Takihara) orchidometer [71], a ring of cards with open spaces to accommodate the shape of a testis (Fig. 15.2). The most reliable method, however, for volume calculation is scrotal ultrasound [72]. It has the best correlation with actual testis size [73]. When dealing with adolescent testes, it is important to realize that testicular growth is not necessary identical in both sides. Kolon and colleagues performed yearly ultrasounds on boys who had 15 % testicular size discrepancy attributed to a varicocele. With time, the majority showed resolution of their size discrepancy [74]. This finding suggested that surgery might not be recommended based on one static measurement and inspired the authors to recommend at least two sequential ultrasounds, 6–12 months apart, before surgical decision is made [74]. In addition to testicular volume measurement, duplex ultrasonography is important to accurately evaluate venous flow reversal as well as vein diameter. A diameter of 3 mm is generally accepted as a cutoff value for diagnosing varicocele [75]. Chiou and colleagues developed an ultrasound scoring system aiming to increase the sensitivity and specificity of varicocele detection. Their system incorporated the following criteria: maximal venous dilatation (score 0–3), the presence of a venous plexus, the sum of the diameters of veins in the plexus (score 0–3), and the change of flow on Valsalva maneuver (score 0–3). A total score of 4 or more was used to define the presence of a varicocele [76].

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Fig. 15.2

Diagram representing the appearance of (a) Prader and (b) Rochester orchidometer s

Some have suggested performing serum hormone evaluation on adolescents with varicocele to assess the integrity of the hypothalamic-pituitary gonadal axis. One must take into account, however, the adolescent’s developmental stage before interpreting test results. In 2013, as part of the CALIPER study (Canadian Library Initiative for Pediatric Reference Ranges), Konforte and colleagues examined sex hormones in a healthy cohort of children aiming to stratify normal reference ranges of fertility hormones by age and Tanner stage [77]. Their results showed that normal ranges in children can generally be considered low in the adult population.

Finding higher than normal levels of serum LH and FSH may suggest the presence of testicular dysfunction [78]. Testosterone may be also reduced in adolescents with varicocele, although this finding is not specifically investigated in this age group. Goldstein and colleagues measured serum testosterone pre- and post-varicocelectomy in 110 infertile men. Despite finding variable preoperative levels, patients with lower serum testosterone had significant improvement in their testosterone level after varicocele surgery that was proportional with the degree of improvement in semen analysis [50].

Evaluating sperm parameters among adolescents is complex mainly because spermatogenesis is in its initial stages and test results can be transitory. Additionally, the test itself is difficult to be executed by younger boys. As a result, studies assessing semen parameters in adolescents are conducted in boys of Tanner stages IV and V [7981]. Abnormal semen parameters such as oligospermia and asthenozoospermia were more prevalent in adolescents with varicocele and seem to be directly related to the degree of testicular volume reduction. Generally, volume reduction of greater than 20 % was associated with twice the odds of finding abnormal semen analysis [80], unlike varicocele grade, which was not found to have any significant influential effect [79].

Management

Varicocele in the adolescent population represents a dilemma to the treating urologist. Historically, adolescent varicocele was left untreated, as there was lack of evidence associating it with infertility . The earliest report suggesting benefit from varicocelectomy in the form of reversal of testicular growth arrest came from Kass and Belman in 1987 [82]. Improvements in testicular growth and semen analyses were also detected in several studies done on adolescents [8385]. More importantly, however, when dealing with adolescent varicocele, concern remains regarding the progressive nature of the condition, which, if left untreated, may continue to affect testicular growth and spermatogenesis [1086]. All these reasons signify a potential advantage to low morbidity surgery, but the question remains as to who will benefit most from surgery. It is obviously impractical and not cost effective to perform surgery for all adolescents with varicocele. On the other hand, it is also unacceptable to allow the deleterious effects of this condition to occur if they may be prevented.

In an effort to identify patients who could benefit from treatment, several variables were evaluated to select those who should have a favorable outcome. Currently, areas used to establish criteria for varicocele repair are as follows.

Varicocele Grade

Varicocele grade has long been subject to extensive research aiming to identify potential connection with testicular dysfunction. Studies by Diamond and Alukal did not find any significant association between grade of varicocele and degree of testicular hypotrophy or defective semen parameters [7987]. Paduch and Zampieri, on the other hand, demonstrated a direct association with testicular growth arrest [8889]. The amount of venous reflux, irrespective of the grade of varicocele, was also found to be an important predictor for the development of infertility [90]. The grade of varicocele was not associated with significant testicular regrowth after surgery, as shown by the work of Decastro and colleagues [91]. They verified that the prevalence of testicular catch-up growth after varicocelectomy is high, even for patients in their early 20s [91]. These results imply that the grade of varicocele by itself should not be the sole indication for treatment.

Testicular Volume

Testicular growth arrest is an established consequence to varicocele in adolescents [879293]. Likewise, its catch-up growth after varicocelectomy is also confirmed [9194]. A decrease in testicular volume has long been the best indication for surgical correction of varicocele. However, not every boy with varicocele and testicular growth arrest will be infertile, and testicular growth is not necessarily symmetrical as the previously presented study by Kolon and colleagues indicated [74]. As a result, the search for a test that would better distinguish between adolescents with a varicocele who will develop infertility and those who will remain fertile is warranted. Currently, the most accepted indication for surgery in adolescents is the presence of testicular volume difference of 2 mL [94].

GnRH Stimulation Test

The normal physiologic response to GnRH stimulation is an increase in FSH and LH secretion from the anterior pituitary. The rationale behind this test is that the damage to the germinal epithelium results in compensatory stimulation of the pituitary gland and subsequent increase in FSH and LH production. As a result a higher than normal baseline FSH and LH is present with subsequent exaggerated response to GnRH stimulation. In theory, the GnRH stimulation test could distinguish between adolescents with varicocele who have abnormal testicular function and those who have normal spermatogenesis. However, in clinical practice, the GnRH stimulation test is expensive, requires multiple serum samples, and lacks an association between abnormal results, growth arrest, and infertility . While studying prepubertal boys, Fideleff and colleagues noticed that changes in the hormonal profile and responses to GnRH stimulation did not have a consistent pattern especially when correlated with the clinical grades of varicocele [95]. Additionally, it is difficult to relate test results only to testicular dysfunction secondary to varicocele in the adolescent population. Hormonal responses can be exaggerated due to testicular growth during this stage of development [96].

Inhibin B Level

Serum inhibin is a protein complex secreted by Sertoli cells. It downregulates FSH synthesis and inhibits FSH secretion. Serum inhibin B measurement in varicocele patients gained interest as it can reflect the integrity of the seminiferous tubules and function of the Sertoli cells. Following GnRH stimulation test, serum inhibin levels failed to aid in stratification of adolescents with varicocele [97]. More recent studies, however, were able to detect significantly lower levels of serum inhibin B in adolescents with varicocele than controls [579899], suggesting it as a useful marker of Sertoli cell damage and a potential indication for surgery.

Semen Analysis

Varicocele is associated with documented abnormalities in semen analysis. In a meta-analysis evaluating the effect of varicocele on semen samples obtained from adolescents, Nork and colleagues confirmed the presence of abnormalities in sperm density, motility, and morphology [100]. Varicocele was associated with alterations in early spermatid head differentiation during spermiogenesis, prompting some to select patients with high incidence of sperm acrosome and nucleus malformations as appropriate candidates for varicocele correction [101].

Lastly, it should be restressed that the practice of performing prophylactic surgery for every adolescent with varicocele is impractical. Currently accepted indications for varicocelectomy in the adolescent population [102] include:

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Surgical Approaches

Surgical options available for adolescent varicocele are similar to those performed on adults. Several surgical classifications exist and are based on the technique (conventional, microsurgical, laparoscopic, and radiologic embolization) or the level of testicular vein ligation (high or low) or whether the gonadal artery is spared or ligated. Generally, advancements in optical magnification and microscopy in recent years eventually influenced varicocele surgery and were favored by an increasing number of urologists. In 1994, Donovan and colleagues surveyed 720 urologists and found that microsurgery was performed only by 6 % of them [103]. In contrast, another survey in 2008 noticed an increasing number of urologists utilizing loop magnification and microsurgery, 48 % and 18 %, respectively [104]. Scrotal varicocelectomy that was once utilized is currently abandoned due to the high incidence of injury to the testicular artery during dissection.

Controversy once existed on whether to spare the testicular artery during the course of varicocele repair. Advocates of total ligation, or nonartery-sparing, techniques claim that sparing the artery can be associated with higher incidence of varicocele recurrence. The main reason for this association is the presence of tiny veins (venae comitantes) along the course of the testicular artery that are usually missed in attempts to spare the artery [105]. However, substantial evidence exists in support of sparing the artery. Damage to the seminiferous tubules with subsequent testicular atrophy is always a possibility with artery ligation [106]. Additionally with the advent use of proper magnification, artery-sparing techniques can be performed without compromising the surgical outcome.

Conventional Varicocelectomy

Retroperitoneal Approach

In 1949, Palomo described the retroperitoneal approach for ligation of internal spermatic vessels [107]. A muscle splitting incision is performed at the level of the internal inguinal ring; the vessels are then identified and ligated at a point that has the fewest arterial and venous branching. A modified artery-sparing Palomo technique is later implemented. Unfortunately, it was associated with a high incidence of postoperative recurrence especially in the adolescent population [108]. Moreover artery sparing without optical magnification was found to be difficult in this age group due to the small caliber of the artery.

Inguinal Approach

The inguinal approach was described by Ivanissevich [109] in 1960. An incision is made over the inguinal canal followed by opening of the external oblique fascia and delivery of the spermatic cord. The exposed cord is then explored, and once the vas deferens is isolated, the veins are identified and divided. Artery-sparing and nonartery-sparing modifications to this procedure were also described. While an effective technique, it has the disadvantage of requiring the patient to have delayed return to full activity due to the extensive muscular dissection in the inguinal canal.

Subinguinal Approach

The subinguinal approach described by Marmar in 1985 [8] is ideally used in adult varicocele, but has gained some acceptance among some pediatric urologists as well. The incision is performed at or near the pubic tubercle avoiding the need to open the external oblique aponeurosis. Advantages of this technique include less pain, smoother recovery, and easier access to the spermatic cord especially among obese patients or those with previous inguinal surgery. However, a greater number of veins are present at such a low level, making the procedure technically challenging.

Microsurgical Varicocelectomy

With the introduction of microsurgery into the field of urology in the mid-1970s [110], it was rapidly utilized to aid in varicocele surgery. The motive for its use was the high incidence of varicocele recurrence and hydrocele formation after conventional surgery. Performing the procedure under magnification allowed for meticulous vein ligation and sparing of lymphatics resulting in lower rates of varicocele recurrence and hydrocele formation, respectively. Microsurgery was used in inguinal and subinguinal approaches with results confirming a superior outcome for varicocelectomy. Reports by Minevich and Goldstein demonstrated a significantly lower recurrence rate and postoperative hydrocele in adolescent patients [111112]. These superior surgical outcomes lead many authors to consider microsurgical varicocelectomy as the gold standard technique for varicocele surgery [113].

Laparoscopic Varicocelectomy

The first report on laparoscopic varicocelectomy came from Hagood and colleagues in 1992 [9]. Since that time, this approach has been utilized with acceptable surgical outcomes. Artery-sparing and nonartery-sparing modifications were performed and the vessels can be divided with hemostatic clips or coagulated with bipolar electrode [114].

Although laparoscopic varicocelectomy is a suitable alternative, it has some significant drawbacks such as the need for pneumoperitoneum, prolonged operative time, and higher cost [103]. Additionally complications such as bowel perforation, major vascular injury, pneumothorax, and incisional hernia, while rare, can be catastrophic complications. Varicocele recurrence and postoperative hydrocele rates with laparoscopy are significantly higher than the subinguinal microsurgical approach. In attempts to reduce the incidence of postoperative hydrocele, lymphatic-sparing techniques were introduced. Rizkala and colleagues compared lymphatic sparing to standard laparoscopic varicocelectomy in 97 patients; the postoperative hydrocele rate was 4.5 % in the lymphatic-sparing group in comparison to 43 % in the standard surgery group [115]. Advancements in the field of laparoscopy were also utilized in adolescent varicocele surgery. Natural orifice transluminal endoscopic surgical (NOTES) procedures [116] and laparoendoscopic single-site (LESS) surgery [117] were utilized in varicocelectomy with promising results. Although such procedures can be very attractive surgical options, they need to be validated in large randomized, clinical trials where patient safety, surgical outcomes, and procedure cost are taken as end points.

Angiographic Embolization

Interventional radiologists have also contributed to the management of varicocele through angiographic antegrade or retrograde embolization or sclerotherapy. Although the minimally invasive nature of such a procedure may have some advantages in adults, it certainly had predictable concerns when duplicated in children and adolescents. Technical difficulties were faced resulting in a failure rate of up to 20 % of cases because of aberrant venous anatomy, difficulty in cannulating the testicular vein, and extravasation of contrast during the procedure [118119]. Other important concerns in this age group are the need for general anesthesia and radiation exposure while performing the procedure. Although these reasons make percutaneous angioembolization a less favorable procedure for treating adolescent varicocele, recent studies reflecting advancements to this field of medicine indicate that it still can be considered as another potential alternative [120].

Several comparative studies were made to evaluate different surgical approaches in adult varicocele surgery. Al-Said and colleagues compared open, laparoscopic, and microsurgical approaches in 446 varicocelectomies. The incidence of postoperative hydrocele was 2.8 %, 5.4 %, and 0 %, respectively. Varicocele recurrence was seen in 11 % of the conventional group, 17 % of the laparoscopic group, and 2.6 % of the microsurgical group. Compared to preoperative values in the three groups, postoperative semen parameters specifically sperm count and motility were significantly higher in the microsurgical group [121]. In a recent meta-analysis of 35 randomized controlled trials and observational studies, Wang and colleagues examined improvements in semen analysis and reported complication rates in various varicocele treatments [122]. Again, microsurgery had the best improvement in sperm density and sperm motility and the least reported complication rate. In adolescents, however, microsurgery was introduced at a later stage [111], but, despite that, results of recent reviews indicate comparable results to those seen in the adult population [123].

Conclusion

The management of adolescent varicocele can be challenging to the practicing urologist. Over the past decade, tremendous research has helped unveil some of its uncertainties. Longer-term studies are needed to understand the exact influence of varicoceles on future fertility and help identify the best approach for its management.

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