Increased Rotational Mobility of the Testis After Vasectomy

Article Increased Rotational Mobility of the Testis After Vasectomy A Sonographic Study Eugenio O. Gerscovich, MD, Christopher W. Park, MD, Michelle Z. Dulude, BA, John P. McGahan, MD, Rebecca Stein-Wexler, MD, Tamara A. Greasby, MS, Laurel A. Beckett, PhD Objective. The purpose of this study was to evaluate for increased mobility of the testis in postvasectomy patients by observing changes in the position of the testis-epididymis complex (TEC). Methods. This was a retrospective study of 29 postvasectomy patients compared with 29 control patients without a history of vasectomy who were referred for scrotal sonography for various clinical indications over a 1 year-period. The position of the TEC was compared between the two groups. Results. The postvasectomy group had medial or posteromedial rotation in 13 of 58 testes (22%) compared with 3 of 58 (5%) in the control group. Conclusions. Our study found a statistically higher incidence of medial rotation of the testis in the vasectomy group compared with the control group. Given our findings, it seems reasonable to assume that iatrogenic changes to the structural support mechanism of the testis occur when vasectomy is performed, with a resultant increase in the mobility of the testis within the scrotum. Key words: epididymis; scrotal sonography; sonography; testis; vasectomy. Abbreviations TEC, testis-epididymis complex Received July 24, 2008, from the Department of Radiology, University of California, Davis Medical Center, Sacramento, California USA (E.O.G., C.W.P., J.P.M., R.S.-W.); and School of Medicine (M.Z.D.), Graduate Group in Biostatistics (T.A.G.), and Department of Public Health Sciences, Division of Biostatistics, School of Medicine (L.A.B.), University of California, Davis, Sacramento, California USA. Revision requested July 26, 2008. Revised manuscript accepted for publication August 12, 2008. We thank Angela Michelier (Department of Radiology, University of California, Davis) for administrative assistance and manuscript preparation. Statistical support for this study was made possible by grant UL1 RR024146 from the National Center for Research Resources, a component of the National Institutes of Health (NIH), and the NIH Roadmap for Medical Research. Address correspondence to Eugenio O. Gerscovich, MD, Department of Radiology, University of California, Davis Medical Center, 4860 Y St, Suite 3100, Sacramento, CA 95817 USA. E-mail: eugenio.gerscovich@ucdmc.ucdavis.edu Vasectomy is one of the most effective methods of male fertility control. In the United States, approximately 500,000 vasectomies are performed annually. It is a relatively simple procedure and is typically performed under local anesthesia on an outpatient basis. It results in few acute or chronic clinical complications. 1 Although prior studies have evaluated intrinsic structural changes to the epididymis after vasectomy, such as an increased incidence of epididymal tubular ectasia and congestive epididymitis, to the best of our knowledge, no sonographic investigations describing increased mobility of the testis have been reported. 2 6 Our study originated after observation of medial testis rotation in several postvasectomy patients referred for sonography of the scrotum. 2008 by the American Institute of Ultrasound in Medicine J Ultrasound Med 2008; 27:1667 1672 0278-4297/08/$3.50

Increased Rotational Mobility of the Testis After Vasectomy Materials and Methods This study was approved by the Human Subjects Review Committee of our institution. We performed a retrospective analysis of 29 patients with a history of vasectomy who had been referred for scrotal sonography for various indications over a 1-year period (Table 1). The patients age range was 38 to 70 years (mean, 51 years). We also reviewed a control group of 29 patients who were referred for scrotal sonography for similar indications but who did not have a history of vasectomy. For these patients, the age range was 27 to 71 years (mean, 47 years). Both groups of patients were selected randomly between May 2002 and May 2003. The same study population was used in a previous publication, 2 with the exception that we excluded 1 patient from the vasectomy group because his sonograms were not available for review at this time. To match this, we excluded 1 patient from the control group. This excluded patient was randomly selected by picking a number because all of the patients in the study had numbers associated with their names. Examinations were performed with an Acuson 128XP/10 or Sequoia 512 scanner (Siemens Medical Solutions, Mountain View, CA). Several linear array transducers were used with frequencies of 6 to 15 MHz. Color Doppler imaging was performed on all patients. Sonographic findings involving the scrotal contents (epididymis and testes) were recorded at the time of the initial examination. The technique for gray scale and Doppler imaging was set on the scrotal side considered normal and Table 1. Indications for Sonography in Patients of the Vasectomy (n = 29) and Control (n = 29) Groups Indication for Group Group Sonography Patients, n Patients, n Scrotal mass 15 6 Scrotal pain 10 13 Scrotal enlargement 6 9 Trauma 0 1 Inguinal hernia 1 1 Asymmetric size 0 3 Groin pain 0 1 Modified with permission from Reddy et al. 2 Some patients had more than 1 indication. unchanged when scanning the contralateral side. The long axis of each testis was identified, irrespective of its relationship to the patient s body planes. The short axis of the testis was obtained at 90 from the long axis. Images of each testis and epididymis were obtained individually and then side by side for comparison. The scrotal sac and tunica vaginalis were imaged. Possible abnormalities were identified. For the purpose of this study, the position and orientation of the testis within the scrotum were determined by evaluating the location of the testis-epididymis complex (TEC). The TEC is defined as the junction of the epididymis and the testis at the medias tinum. The location of this structure was determined by its relationship to the testis as visualized on an axial image when possible. We classified the location of the TEC into 6 areas as follows: (1) medial, (2) posteromedial, (3) posterior, (4) posterolateral, (5) lateral, and (6) anterolateral (Figure 1). This was accomplished by finding the location of the TEC directly or, occasionally and indirectly, by changes caused by tubular ectasia of the rete testis (Figures 2 6). For the purpose of our study, we accepted as normal the posterior, lateral, posterolateral, and anterolateral locations. We considered the testis rotated when the TEC was identified in a medial or posteromedial location. Frequencies and percentages were calculated for each position. In a few cases, the position of the testis was indeterminate secondary to nonvisualization of the Figure 1. Diagram of an axial view of the right testis representing possible locations of the TEC. Dark-shaded areas are consistent with increased mobility of the testis; light-shaded areas indicate positions within normal limits. 1668 J Ultrasound Med 2008; 27:1667 1672

Gerscovich et al TEC, and those testes were excluded from the tabulation. The effect of vasectomy on the odds of rotation was estimated by logistic regression adjusted by a generalized estimating equation approach for having testicular data in pairs. 7 In the primary analysis, testes with indeterminate positioning were omitted; secondary analyses examined the effects of this choice. We also compared the overall proportion of men with at least 1 rotated testis by the Fisher exact test. All analyses were performed with SAS/STAT software (SAS Institute Inc, Cary, NC), and all tests were 2 sided at a significance level of P <.05. Results Acute scrotal findings in our patients, such as epididymitis, epididymo-orchitis, scrotal hematoma, and testicular rupture, are listed in Table 2. Nonacute findings are listed in Table 3. These findings were excluded from our study because they were discussed in the aforementioned publication. 2 In that publication, thickened epididymides, epididymal tubular ectasia, and sperm granulomas were found to be statistically more frequent in postvasectomy patients. In the vasectomy group, 29 patients were examined, with 56 testes evaluated. The positions of 2 TECs were indeterminate secondary to orchiectomy (n = 2). Within this group, 13 of 56 TECs were positioned at either the medial or posteromedial aspect of the testis (Table 4). In the control group, 29 patients were examined, with 54 testes evaluated. The positions of 4 TECs were indeterminate secondary to cryptorchidism (n = 2), obscuration by a testicular mass (n = 1), and testicular rupture (n = 1). Within this group, 3 of 54 TECs were positioned at the medial or posteromedial aspect of the testis (Table 4). Figure 3. Normal position of the mediastinum in the lateral aspect of the testis in 2 nonvasectomy patients. A, Axial view of right testis. The arrow denotes the mediastinum. B, Longitudinal view of the left testis (T) with a scan obtained through the lateral aspect of the testis. Arrowheads denote the mediastinum. A Figure 2. Axial view of the right testis in a nonvasectomy (control) patient showing a normal position of the hyperechoic testicular mediastinum (arrow) at the posterior aspect of the testis (T), from which the position of the TEC can be inferred. B J Ultrasound Med 2008; 27:1667 1672 1669

Increased Rotational Mobility of the Testis After Vasectomy Figure 4. Axial view of the right testis (T) in a postvasectomy patient showing a normal posterior position of the epididymis and TEC (arrow). The epididymis shows tubular ectasia secondary to vas occlusion. In the vasectomy group, 22% of the TECs were medial or posteromedial, compared with 5% in the control group (Table 4). In this group, 4 of 28 right testes (14%) and 9 of 28 left testes (32%) were rotated. Of those patients, 4 of 29 men (14%) had both testes rotated. In the control group, 2 of 28 right testes (7%) and 1 of 28 left testes (4%) were rotated. Of those patients, none had bilateral rotation. In logistic regression adjusted for within-person pairing of testes, the odds of rotation were 5.18-fold greater for the vasectomy group than for the control group (95% confidence interval, 1.33- to 20.1-fold greater; P =.018.). The withinperson correlation was estimated as 0.22, suggesting a modest tendency for greater odds of a second similar finding in a man with 1 testis rotated. Analysis of results for each man, estimating the odds of having at least 1 testis rotated compared with having both normal, gave a slightly lower estimate of the effect of vasectomy, with an odds ratio of 3.9, and did not achieve statistical significance. This most likely reflects the reduced effective sample size of 58 people rather than 116 testes. Secondary analysis including indeterminate cases as unaffected gave essentially identical results (data not shown). Discussion The epididymis is a coiled tubular organ that attaches to the posterolateral or posterior surface of the testis at the mediastinum. It connects the efferent ducts from the testicle to its vas deferens and also functions in the maturation and storage of sperm. Numerous techniques are used when performing vasectomy, although all share 4 common steps essential to successful sterilization: isolation, delivery, and interruption of the vas deferens and management of its ends. 8 Two methods are commonly used to manage the vasal ends: an open-ended technique and a closed-ended technique. Often, a combination of techniques is used on the basis of a given clinician s preference and experience. The surgical technique could not be obtained from the medi- Figure 5. Axial view of the right testis (calipers) in a postvasectomy patient showing a medial position of the mediastinum (arrow) and TEC. Figure 6. Axial view of the right testis in a postvasectomy patient with tubular ectasia of the rete testis (arrow). The medial position of the rete testis indicates rotation of the TEC. 1670 J Ultrasound Med 2008; 27:1667 1672

Gerscovich et al Table 2. Acute Sonographic Findings in Patients of the Vasectomy (n = 29) and Control (n = 29) Groups Group Group Acute Finding Patients, n Patients, n Epididymitis 3 5 Epididymo-orchitis 0 2 Hematoma 2 0 Hematocele 1 0 Testicular rupture 0 1 Scrotal wall edema 0 1 Modified with permission from Reddy et al. 2 cal histories of many of our patients to determine whether one method affected mobility more than others. A study by Puttemans et al 9 indicates that in most patients, the epididymal body (TEC) is located lateral to the testis. A considerably less common location is posterior to the testis. None is found in the medial aspect. On this basis, for our study we called testes normally positioned when the epididymides were located laterally or posteriorly, and we called them rotated when medially located. It may be said that testes are highly mobile, and by chance they could be located in one position or another during scanning. That is true, but our thought is that the same chance of this happening would have existed for the patients in both the postvasectomy and control groups, thus canceling this variable. It is also of concern that the transducer might have been rotated during scanning. We think this was very unlikely because of the high level of experience of our sonographers. Given the anatomic continuity of the epididymis and vas deferens, it is our hypothesis that medial or posteromedial rotation of the TEC is suggestive of postvasectomy status (not exclusively) and is most likely the result of fascial disruption and discontinuity of the vas during the procedure. Our study seemed to support this hypothesis, with an estimated 5-fold increase in the odds of rotation. Additional studies including a larger number of patients would be helpful for corroboration of our findings. In summary, a medial or posteromedial position of the TEC should be an additional sonographic finding favoring the diagnosis of postvasectomy status. Table 3. Nonacute Sonographic Findings in Patients of the Vasectomy (n = 29) and Control (n = 29) Groups Group Group Nonacute Finding Patients, n (%) Patients, n (%) Epididymal cysts 12 (41) 12 (41) Hydrocele 12 (41) 14 (48) Thickened epididymis 16 (55) 5 (17) Tubular ectasia of epididymis 13 (45) 2 (7) Tubular ectasia, rete testis 3 (10) 2 (7) Thickened epididymis with 11 (38) 2 (7) tubular ectasia Varicocele 8 (28) 9 (31) Testicular cysts 2 (7) 2 (7) Choriocarcinoma 0 (0) 1 (3) Cryptorchidism 0 (0) 2 (7) Orchiectomy 2 (7) 0 (0) Inguinal hernia 0 (0) 1 (3) Testicular microlithiasis 0 (0) 3 (10) Granulomas 3 (10) 0 (0) None 3 (10) 3 (10) Modified with permission from Reddy et al. 2 Some patients had more than 1 finding. Table 4. Anatomic Position of the TEC in Testes of the Vasectomy (n = 58) and Control (n = 58) Groups Anatomic Position Group Group of TEC (Segment) a Testes, n (%) Testes, n (%) Rotated 13 (22) 3 (5) Medial (1) 12 (21) 2 (3) Posteromedial (2) 1 (2) 1 (2) Normal 43 (74) 51 (88) Posterior (3) 12 (21) 20 (34) Posterolateral (4) 7 (12) 8 (14) Lateral (5) 23 (40) 23 (40) Anterolateral (6) 1 (2) 0 (0) Indeterminate 2 (3) 4 (7) Cryptorchidism 0 (0) 2 (3) Orchiectomy 2 (3) 0 (0) Testicular mass 0 (0) 1 (2) Testicular rupture 0 (0) 1 (2) a As in Figure 1. J Ultrasound Med 2008; 27:1667 1672 1671

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