You are in: eMedicine Specialties > Radiology > GENITOURINARY VaricoceleArticle Last Updated: Jul 10, 2008AUTHOR AND EDITOR INFORMATIONSection 1 of 12
  Author: Ali Nawaz Khan, MBBS, FRCS, FRCP, FRCR, LRCP, Chairman of Medical Imaging, Professor of Radiology, NGHA, King Fahad National Guard Hospital, King Abdulaziz Medical City, Riyadh, Saudi Arabia Ali Nawaz Khan is a member of the following medical societies: American Institute of Ultrasound in Medicine, Radiological Society of North America, Royal College of Physicians, Royal College of Physicians and Surgeons of the United States, Royal College of Radiologists, and Royal College of Surgeons of England Coauthor(s): Sumaira MacDonald, MBChB, PhD, MRCP, FRCR, Lecturer, Sheffield University Medical School; Endovascular Fellow, Sheffield Vascular Institute; Klaus L Irion, MD, PhD, Consulting Staff, The Cardiothoracic Centre Liverpool NHS Trust, The Royal Liverpool University Hospital, UK Editors: Harris L Cohen, MD, FACR, Vice Chairman/Associate Chairman (Research Activities), Director, Division of Body Imaging, Professor of Radiology, Stony Brook School of Medicine; Visiting Professor of Radiology, Johns Hopkins School of Medicine; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Joshua A Becker, MD, Professor, Department of Radiology, New York University School of Medicine; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Clinical Assistant Professor of Radiology, University of Washington Medical School Author and Editor Disclosure Synonyms and related keywords: varicocele, spermatic cord venous dilatation, spermatic cord vein dilatation, spermatic cord vein dilation, spermatic cord venous dilation, pampinocele, dilatation of veins of pampiniform plexus, varicosity of pampiniform plexus veins, incompetent valves of spermatic veins, bag of worms, absent valves of spermatic veins, male infertility, internal spermatic vein, pampiniform plexus, male infertility, scrotal swelling, scrotal pain INTRODUCTIONSection 2 of 12
  BackgroundVaricoceles develop as a result of dilatation and tortuosity of veins of the pampiniform plexus secondary to retrograde flow into the internal spermatic vein (ISV). A varicocele is a common abnormality, occurring in approximately 15% of men. Some patients may have scrotal pain and swelling, but more importantly, a varicocele is considered to be a potential cause of male infertility.1, 2, 3 This relationship is controversial, but improved fertility and sperm quality have been reported after treatment, including occlusive treatment for varicoceles. On physical examination, large varicoceles are easily identified as the classic "bag of worms" surrounding the testis. Ultrasonography, particularly Doppler ultrasonography, allows accurate diagnosis of varicoceles, even subclinical varicoceles.1, 4, 5, 6, 7 PathophysiologyA varicocele (ie, dilatation of the veins of the pampiniform plexus) may be caused by incompetent or absent valves of the spermatic veins. The right spermatic vein enters obliquely into the inferior vena cava and is somewhat protected anatomically. Idiopathic varicoceles are more common on the left, where the right-angled entry of the left spermatic vein into the relatively horizontal left renal vein leads to a greater incidence of varicoceles. Far less usual causes of a varicocele may be due to the compression of a renal vein by tumor, an aberrant renal artery, and an obstructed renal vein. Other rare causes implicated in the causation of varicoceles include azygos-hemiazygos continuation with an anomalous intrahepatic connection (bilateral varicocele), aortic aneurysm associated with an aorta–left renal vein fistula,8 false aneurysm from an aortic graft, and inferior vena caval obstruction. The diagnosis of a varicocele is clinically important for several reasons. Varicoceles cause pain, which is usually experienced as a dragging discomfort. Solitary right varicoceles may be associated with renal and retroperitoneal masses, including renal cell carcinomas. The presence of a varicocele may be associated with infertility. Factors implicated in the causation of infertility include impaired spermatogenesis and sperm motility secondary to elevated scrotal temperature, slow blood flow or stasis within the dilatated vein, and reflux of toxic material from the adrenal vein. Testicular biopsy in patients with infertility and varicoceles show some changes that are indistinguishable from those of primary testicular failure. These include a variety of changes in the Leydig and Sertoli cells. Venous hypertension in the spermatic cord veins may be responsible for the aforementioned effects on the testis. The size of the varicoceles may not be a key predictor of infertility in that size seems to have no relationship to improvement in spermatogenesis after corrective surgery.9 In all probability, subclinical varicoceles may be responsible for the vast majority of cases of male infertility. With Doppler ultrasonography, 2 types of retrograde flow in varicoceles have been described. These include the shunt-type varicocele and the stop-type varicocele (see Image 6).10 The shunt-type varicocele occurs in 86% of patients and is associated with diminished sperm quality as well as with a medium to large varicocele. The stop-type varicocele involves reflux, which is only brief, and the sperm quality is normal and associated with a subclinical varicocele. Shunt-type Doppler flow occurs because insufficient distal valves allow spontaneous and continuous reflux from the internal spermatic vein into the cremasteric vein and the vein of the vas deferens via collateral vessels. The stop type of flow, also known as the pressure type, occurs in patients with intact intrascrotal valves. This type allows only a brief period of reflux from the spermatic vein into the pampiniform plexus when a Valsalva maneuver is performed. Recurrence of varicoceles can be as high 20% in patients after embolotherapy and/or surgical ligation of varicoceles. Hamm et al found that thermography is superior to ultrasonography in the follow-up imaging of patients who had undergone sclerotherapy and who were evaluated for persistent venous disease.11 FrequencyUnited StatesClinical varicoceles occur in 10-15% of men; they are found in 21-39% of men in whom infertility is investigated. The varicoceles are mostly left sided. Subclinical varicoceles have been reported in 40-75% of infertile men. The incidence of bilateral varicoceles varies from 10-70%, with the higher percentage reported by McClure and Hricak in infertile men with palpable and nonpalpable varicoceles.7 InternationalThe frequencies of varicoceles in Europe are similar to those in the United States, but the incidence in the rest of the world is unknown. Mortality/MorbidityPatients with varicoceles may present with vague discomfort or infertility. The most consistent semen abnormality in men with varicoceles is poor sperm motility, followed by abnormal sperm morphology and a reduced sperm count. After varicocele embolotherapy, as many as 50% of subfertile men are able to achieve pregnancy in their female partners. The cost and morbidity related to embolotherapy for varicoceles are less than the cost and morbidity after surgical treatment. With surgery, complications such as a hematocele/hydrocele and epididymitis may develop. An acute varicocele may be a presenting feature of a more serious underlying pathology, such as a retroperitoneal tumor. AgeMen of any age can be affected, although most patients present in early adult life. AnatomyThe components of pampiniform plexus include the location of the ISV in a ventral location, which drains the testis. The vein of the vas deferens is mediodorsal and drains the epididymis. The cremasteric vein on the laterodorsal aspect drains the scrotal wall. All of these veins merge to form the pampiniform plexus. Distal to the superficial inguinal ring, the pampiniform plexus is drained by 3-4 veins traversing the inguinal canal to the abdomen through the deep inguinal ring. These veins coalesce into 2 veins, which ascend in the retroperitoneum; the veins join to form the ISV, before opening into the middle of the renal vein on the left and the inferior vena cava on the right. The left ISV enters the left renal vein directly opposite the adrenal vein. In 20% of patients, the left ISV may immediately split into 2 or 3 branches before entering the left renal vein. An important collateral vein joins the ISV overlying the upper third of the sacroiliac joint. This collateral may communicate with the inferior mesenteric vein and is usually accompanied by a parallel collateral vessel from the inguinal canal. In addition, collateral vessels from the proximal and distal renal veins as well as the capsular vein join the ISV just above or below the upper third of the sacroiliac joint. The testicular veins contain valves. Anatomically, most of the valves are located in the upper 1-6 cm of the ISV. As mentioned earlier, varicoceles are more common on the left, and several anatomic factors have been implicated in the increased incidence of left-sided occurrence of a varicocele, including the 90º junction of the left ISV and the left renal vein. In addition, it has been postulated that the overlying descending colon may impede venous return, particularly when an individual is constipated. The association of proximal compression of the left renal vein by the overlying aorta and the superior mesenteric artery has also been implicated in producing increased venous pressure in the left renal vein and, thus, pressure transmission into the ISV. After sclerotherapy or occlusion of the varicocele, venous return is via the ductus deferens, cremasteric, and scrotal small veins. In an erect posture, the normal diameter of the largest spermatic vein at the level of the inguinal canal is seldom greater than 2.2 mm, as measured with ultrasonography. This measurement increases to 2.7 mm with a Valsalva maneuver. Clinical Details
Most experts believe that varicoceles can potentially cause infertility. Evidence supporting this assumption includes the fact that varicoceles are more common in infertile man than in the general population. Men with varicoceles have abnormalities of the semen and testicular histology; semen quality and pregnancy rates increase after varicocele repair. Acute varicoceles on either side are suggestive of tumors that are either compressing or causing thrombosis of the ISVs. Acute symptomatic varicoceles may be suggested when varicoceles are present solely on the right side or when they remain engorged when the patient is in the supine position. In both adults and children, varicoceles may cause progressive testicular atrophy. Preferred ExaminationUltrasonography is the examination of choice for investigating varicoceles, and it remains the most practical and most accurate noninvasive technique. 1, 5, 6, 7 The role of radionuclide studies and magnetic resonance imaging (MRI) in the investigation of varicoceles is limited; these offer no advantage over ultrasonography. Venography is the most reliable modality for the detection of subclinical varicoceles because the findings demonstrate abnormal retrograde flow into the spermatic veins or pampiniform plexus. However, the procedure remains invasive and is usually reserved for patients undergoing sclerotherapy. The ionizing radiation of computed tomography (CT) scanning limits its use. Limitations of Techniques
DIFFERENTIALSSection 3 of 12
Other Problems to Be ConsideredAberrant renal artery compressing the left renal vein CT SCANSection 4 of 12
FindingsCT scans can demonstrate varicoceles. In one study, 2 transverse scans were obtained with the patient in a supine position during quiet breathing and during Valsalva maneuver.13 The transsectional area of the spermatic cord was 80-100 mm2 on the side without the varicocele and 100-200 mm2 on the affected side. Increased intra-abdominal pressure dilated the veins of the pampiniform plexus, increasing the transsectional area by 40-80% on the side without varicocele and by 100-200% on the side with the varicocele.13 The authors noted that a spermatic cord area (measured at the root of the scrotum) of greater than 100 mm2 without an increased intra-abdominal pressure and an area greater than 200 mm2 with an increased intra-abdominal pressure is indicative of a varicocele. Degree of ConfidenceCT scanning with increased intra-abdominal pressure can be used as a noninvasive method to detect a varicocele and to show proximal extension of the lesion into the inguinal canal. However, exposure to radiation is a disadvantage, and to the authors' knowledge, no comparative studies with ultrasonography have been performed. The sample of patients in whom the use of CT scanning has been reported is small, and no firm conclusions can be drawn from the study described above (see CT Scan, Findings). False Positives/NegativesTo the authors' knowledge, no literature regarding false findings with CT scanning is available. MRISection 5 of 12
Findings
Degree of ConfidenceThe role of MRI in the diagnosis of varicoceles has not been established because an insufficient number of patients have been examined with MRI. False Positives/NegativesTo the authors' knowledge, no data are available regarding false findings with MRI. ULTRASOUNDSection 6 of 12
FindingsUltrasonographic findings in varicoceles include the following:
Degree of ConfidenceUsing the diameter as the criteria of venous channel dilatation, Hamm et al found that ultrasonography had a sensitivity of 92.2%, a specificity of 100%, and an accuracy of 92.7%.11 Ultrasonography is capable of demonstrating both palpable and subclinical varicoceles. False Positives/NegativesEpidermoid cysts and spermatoceles may mimic varicoceles. If in doubt, color Doppler ultrasonographic findings are diagnostic. Intratesticular varicoceles may mimic tubular ectasia. NUCLEAR MEDICINESection 7 of 12
FindingsTechnetium-99m (99mTc)–labeled red blood cells are the radiopharmaceutical agent of choice for the evaluation of varicoceles, although other radionuclides have been used as well. Images are obtained with the patient in both the supine and erect positions. Static images reveal moderate to intense intrascrotal accumulation of the labeled red cells; this accumulation may be discrete or patchy. Both palpable and nonpalpable varicoceles have been identified on blood-pool images, but cases of reflux without increased blood pool usually cannot be identified on static images.15 A Valsalva maneuver during image acquisition may be helpful in detecting subclinical cases. The importance of detecting subclinical cases is related to the proposed association of varicoceles to infertility. The use of dynamic scanning is controversial. A reduction in early blood flow on the affected side has been observed. Dynamic images allow calculation of the difference in arrival time of radioactivity between the iliac artery and the pampiniform plexus; this time is believed to shorten with increasing grades of varicoceles. Degree of ConfidenceVaricoceles have been identified during blood-pool imaging, but independent correlation in subclinical cases is difficult. As with most scrotal pathologies, bilateral disease is difficult to confirm on scrotal radionuclide imaging. The sensitivity for clinically apparent varicoceles has been reported to be 90%. The specificity is difficult to determine. False Positives/NegativesAccurate assessment of the number of false findings is difficult to perform. ANGIOGRAPHYSection 8 of 12
FindingsVenography is the most reliable modality for the detection of small or subclinical varicoceles because findings demonstrate abnormal venous blood reflux in a retrograde fashion into the ISVs and the pampiniform plexus. Degree of ConfidenceBecause of the invasive nature of venography, the technique is usually reserved for use in patients undergoing occlusive therapy for mapping of the venous anatomy. Occasionally, it is used in symptomatic patients when the diagnosis is equivocal with other methods. False Positives/NegativesTesticular veins often spasm, and rarely, opacification of the vein with contrast medium may be difficult. Moreover, problems may be encountered in cannulating the right testicular vein. INTERVENTIONSection 9 of 12
Indications for embolic therapy of the left ISV include a varicocele associated with infertility, painful varicoceles, and a large varicocele in a child or adolescent with testicular atrophy or recurrent varicocele after previous embolization or surgery. Indications for embolization of a right ISV include a palpable varicocele associated with infertility and a recurrent or persistent left varicocele without apparent collaterals to the ISV, as demonstrated with left renal venography. Angiographic treatment of a varicocele consists of the occlusion of the ISV with the interruption of retrograde venous flow. Effective occlusive therapy should eliminate recurrence. The procedure is performed on an outpatient basis. A preliminary diagnostic venogram is obtained first. Selective catheterization of the left ISV, in which most varicoceles occur, is straightforward. Treatment in the right ISV may be more problematic because of anatomic factors. Various embolic agents have been used to occlude the ISV, including detachable balloons, stainless steel coils, and various sclerosing agents such as sodium tetradecyl sulfate (STS).16 The size of occlusive devices is selected according to the diameter of the ISV, and often, devices 10 mm or larger are necessary. (Note: Polyvinyl alcohol particles, particularly small ones, are not effective agents for the embolization of varicoceles.) Any occlusive devices should be placed inferior to the upper one third of the sacroiliac joint to prevent recurrence (see Anatomy). Medical/Legal Pitfalls
Related Medscape topics: Special Concerns
ACKNOWLEDGMENTSSection 10 of 12
The authors and editors of eMedicine gratefully acknowledge the contributions of previous coauthor Dr Paul Winarso to the development and writing of this article. MULTIMEDIASection 11 of 12
REFERENCESSection 12 of 12
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