of segmental testicular infarction an infrequent testicular disorder rarely described in the radiologic

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1 Genitourinary Imaging Fernández-Pérez et al. Radiology of Testicular Infarction Gabriel C. Fernández-Pérez 1 Francisco M. Tardáguila 1 María Velasco 1 Celso Rivas 1 John Dos Santos 2 Javier Cambronero 2 Carmen Trinidad 1 Pilar San Miguel 3 Fernández-Pérez GC, Tardáguila F, Velasco M, Rivas C, Dos Santos J, Cambronero J, Trinidad C, San Miguel P Received pril 28, 2004; accepted after revision ugust 24, Radiology Department, Povisa Medical Center, Salamanca, St , Vigo (Pontevedra) Spain. ddress correspondence to G. C. Fernández-Pérez (gabrife@teleline.es). 2 Urology Department, Povisa Medical Center, Salamanca, Vigo, Spain. 3 Pathology Department, Povisa Medical Center, Salamanca, Vigo, Spain. JR 2005;184: X/05/ merican Roentgen Ray Society Original Report Radiologic Findings of Segmental Testicular Infarction OJECTIVE. Our objective was to describe the radiologic findings of segmental testicular infarction and to establish a proper diagnosis that can avoid orchiectomy. CONCLUSION. The presence of a triangular-shaped avascular intratesticular lesion on sonography or MRI and enhancement of the surrounding borders on enhanced MR images may suggest a presurgical diagnosis of segmental testicular infarction and therefore avoid a total orchiectomy in these patients. egmental testicular infarction is S an infrequent testicular disorder rarely described in the radiologic literature and usually diagnosed after orchiectomy [1]. Several etiologic mechanisms are involved, such as acute epididymoorchitis [2] and hematologic disorders such as sickle cell disease or polycythemia [3], and the disorder has been associated with vaculitis, such as in hypersensitivity angiitis [4]. However, no ample series supports a clear cause because fewer than 40 cases have been reported in the literature. This entity affects patients between the second and the fourth decades of life, although it occasionally has been reported in neonates [5, 6]. The imaging method of choice for diagnosis is color Doppler sonography, which shows a flowless area and normal remaining testicular parenchyma [7 9]. However, on many occasions, segmental testicular infarction cannot be distinguished from a tumor with low flow, especially if the tumor is small [10 16]. Recently, some authors have proposed a role for MRI in the diagnosis of segmental testicular infarction using contrast sequences [17]. In this article, we describe the most relevant radiologic findings in 12 cases of segmental testicular infarction studied with sonography and MRI. Materials and Methods Patient Evaluation The study population was selected from a database of 342 patients with scrotal diseases for whom clinical and imaging data had been obtained between January 1996 and January The possibility of segmental testicular infarction was queried in 12 patients (3.5% of our database; age range, years; median, 38 years) who were studied with color Doppler sonography and MRI, with the latter performed for research purposes during the first 72 hr after sonography. In five patients, the final diagnosis was histologically proven by surgery, three by total orchiectomy and two by partial orchiectomy. In the other seven patients, the inclusion-criteria diagnosis was established by radiologic suspicion using both imaging methods, sonography and MRI, when an avascular intratesticular area without mass effect was associated with negative tumoral markers and followed up monthly for 6 months using sonography. In these patients for whom follow-up was proposed to confirm the diagnosis, the persistence of negative tumoral markers and the absence of relevant imaging changes in size and morphology were used to prove the benign nature of the lesion. In three patients, MRI was also performed to evaluate possible changes during the first month. Our institutional review board did not require its approval or a special informed consent form for our study. The patients were informed according to the standard information form for MRI. No patient was JR:184, May

2 Fernández-Pérez et al. excluded from this technique because of contraindications. TLE 1 Patient Characteristics Imaging Techniques Sonography was performed using high-resolution (linear 7-12 MHz transducer) units (Power Vision, Toshiba; or Logiq 500, GE Healthcare). Gray-scale, color-flow Doppler, and power Doppler sonography were used to examine each testis for the presence or absence of intratesticular blood flow. The power level, threshold, persistence, and wall filter were individually adjusted to maximize the detection of blood flow. In four patients, MR images were obtained with a 0.5-T unit (Gyroscan 5T, Philips Medical Systems) using a circular surface coil. The imaging parameters were as follows: axial and coronal (or sagittal) unenhanced and enhanced T1-weighted spin-echo images (TR/TE, 572/20) and T2-weighted turbo spin-echo images (3,257/120). For both sequences, the section thickness was 6 mm, the intersection gap was 0.6 mm, the image matrix was , and the field of view was mm. Eight patients were studied with a 1.5-T unit (Intera NT, Philips Medial Systems) with phased-array coil and axial and coronal (or sagittal) sequences using unenhanced and enhanced T1-weighted turbo spin-echo images (575/11) and T2-weighted turbo spin-echo images (5,480/140) with 4-mm section thickness and 0.4-mm gap. The image matrix was , and the field of view was 200 mm. Parallel sensitivity-encoded imaging also was used, with a factor of two, decreasing the acquisition time by half. bolus of gadolinium chelate (gadodiamide, Omniscan, mersham Health), 0.1 mmol per kilogram of body weight, was injected at 3 ml/sec using a power injector (Spectris, Medrad MR Injector System). Images were acquired immediately after administration of the contrast material. ll patients were examined in the supine position and with a folded towel placed between the thighs to avoid motion artifacts from spontaneous movements of the testes. The entire examination took approximately min. Image Interpretation and Data nalysis Two radiologists with experience in testicular pathology evaluated the sonography and MR images by consensus. The retrospective reviewers were aware of the presence of segmental testicular infarction. The size, location, morphology, signal intensity, vascularization, and pattern of enhancement after contrast material administration on MRI were analyzed. The patient s age and clinical signs and the possible causes of the infarction were also recorded. Numeric or qualitative variables were reported as median and percentage. Results n acute scrotum was the most frequent clinical presentation, being observed in eight patients (67%). No cause could be found in more than half the patients (7/12). However, three patients (25%) presented with an inflammatory disease (epididymoorchitis), and in two (17%), the affected testis had recently undergone surgery (Table 1). On sonography, all segmental testicular infarctions were solid, and avascular lesions were in the right testis in seven patients (58%). The median size was 9 mm, and the range was 3 19 mm. Ten (83%) of the 12 segmental testicular infarctions were in the upper or middle part of the testis (Fig. 1). Segmental testicular infarctions were usually wedgeshaped nine cases on sonography (75%) and 10 on MRI (83%) with the vertex at the testicular mediastinum (Fig. 2). However, a round morphology was also observed in two patients and with both methods (Fig. 3), the lesion being confused with an intratesticular tumor. lthough those lesions showed absence of vascularity and negative tumoral markers, patients underwent total orchiectomy with pathologic results of segmental testicular infarction. MRI on T2-weighted images showed well-defined borders in all cases with a low (8/12), high (2/12), or intermediate (2/12) signal intensity in the lesion. In 10 patients, the lesion was imperceptible on unenhanced T1-weighted images; however, a central area with high signal intensity representing hemorrhagic foci was seen in two patients (17%) (Fig. 4). On enhanced T1- weighted images, segmental testicular infarction showed an enhanced rim surrounding the lesion. This finding was noted in 11 patients (92%), helping to delimit the lesion (Figs. 4 and 5). slight retraction of the tunica albuginea adjacent to the lesion was detected in four patients, three of whom had chronic testicular pain. However, in one who presented with an acute scrotum, the capsular retraction was observed 1 month later during the first checkup (Fig. 4). Discussion Segmental testicular infarction is a partial ischemic process observed on color Doppler sonography as an area without vascular flow. However, in some cases, differentiation of Patient No. ge (yr) Clinical Presentation Testicular Side Testicular Location Personal ntecedents Tumoral Markers STI Shape Enhanced orders 1 42 cute scrotum Left Upper Vasectomy Negatives Wedge No 2 32 cute scrotum Right Lower Unknown Negatives Wedge Yes 3 38 Chronic pain Left Upper Epididymitis Negatives Wedge Yes 4 25 Chronic pain Right Upper Orchiopexy Negatives Wedge Yes 5 38 cute scrotum Right Medium Unknown Negatives Wedge Yes 6 54 cute scrotum Left Upper Unknown Negatives Round Yes 7 32 cute scrotum Right Lower Unknown Negatives Wedge Yes 8 35 cute scrotum Right Upper Unknown Negatives Wedge Yes 9 42 cute scrotum Right Medium Unknown Negatives Wedge Yes cute scrotum Left Upper Epididymitis Negatives Round Yes Chronic pain Right Medium Epididymitis Negatives Wedge Yes symptomatic Left Upper Unknown Negatives Wedge Yes Note. STI = segmental testicular infarction JR:184, May 2005

3 Radiology of Testicular Infarction Fig. 1. MRI of 42-year-old man with acute scrotal pain in left testicle., Coronal enhanced T1-weighted turbo spin-echo image (TR/TE, 575/11; 4-mm section thickness) shows segmental testicular infarction in upper hemisphere of testicle. Lesion is avascular with subtle rim enhancement (arrowhead)., Coronal T2-weighted turbo spin-echo image (5,480/ 140) shows lesion with low signal intensity and welldefined borders (arrowhead). segmental testicular infarction from a small intratesticular tumor, which may have a low flow, is difficult [7 16]. Diagnosis may be aided by MRI because it easily shows the borders of the segmental testicular infarction not only on T2-weighted sequences but also on enhanced images. In sequences after contrast use, one of the most relevant characteristics of segmental testicular infarction was the presence of a surrounding markedly enhanced rim, which was seen in more than 90% of the patients in our series. This feature was also described by Kodama et al. [17] in one patient and by Ruibal et al. [18] in three patients with segmental testicular infarction. nother common finding shown by both imaging methods was the triangular morphology with the vertex directed toward the rete testis. In this setting, this morphology is similar to focal infarctions in other organs, such as spleen or kidney [19]. Segmental testicular infarctions with a wedge shape have not been described thoroughly in previous publications, probably because most cases have been studied by sonography, and the borders of the lesions are frequently irregular and poorly defined on sonograms. In some cases, MRI also can show hemorrhagic foci of high signal intensity on T1-weighted images [19, 20]. In the evolution of segmental testicular infarction, we did not observe any significant changes in its morphology, signal intensity, or enhancement. However, we observed a slight retraction of the tunica albuginea in the area contacting the lesion, indicating a slight loss of lesion volume due to hyalinization and fibrosis occurring in the infarcted tissue. These findings were shown histologically for a surgically removed lesion (Fig. 5). This fea- Fig. 2. Images of 38-year-old man with previous history of epididymitis in left testicle, 1 month before., Gray-scale sonogram with linear 7-MHz transducer shows triangular lesion in left testicle (arrowhead) with vertex pointed to rete testis., Color Doppler sonogram shows hypovascular area with practically no flow in lesion (arrowhead); only small vessel was seen in outer border. Rest of testicular parenchyma has normal vasculature. Inset: T1-weighted turbo spin-echo image after contrast use shows avascular lesion with characteristic triangular shape (arrowhead). No changes were observed during follow-up. JR:184, May

4 Fernández-Pérez et al. D ture also has been reported by Sentilhes et al. [21] for a patient with segmental testicular infarction checked after 3 months, for whom orchiectomy was avoided. In our series, the albuginea retraction was seen in three patients with chronic pain but also could be observed in the first month of follow-up for a patient presenting with acute scrotum but for whom the retraction was not present on the initial study (Fig. 4). On the basis of evolution time and histologic results, the possibility of a repairing process or even a marked-intensity necrosis with rapid fibrosis of the lesion might explain the findings. The cause was unclear for most of the cases reported, although some were described as being associated with an inflammatory event (epididymitis or orchitis), vasculitis, or hematologic disorders (sickle cell disease and polycythemia) [1 4]. In our series, the only antecedent that could be shown was epididymoorchitis, in three patients. Ledwidge et al. [22] and Dogra [23] described a patient with associated bell-clapper anomaly (a deformity or anomaly that leaves the testis free to swing and rotate within the tunica vaginalis), suggesting that the cause of segmental infarction was torsion and detorsion of the testis, producing ischemia in the upper pole of the testis and, secondarily, hyperemia of the lower pole. In our series, one patient presented with a retractile testis and repeated episodes of testicular pain, because of which the testis had to Fig year-old man with acute pain in left testicle who had clinical symptoms of epididymoorchitis., Coronal sonogram shows round intratesticular lesion with nondefined borders in upper pole of left testis. Lesion was reported as testicular tumor (asterisk). MRI was also performed., Sagittal T2-weighted image (TR/TE, 3,257/120; 6-mm thickness). rrowhead indicates the round lesion with low signal intensity. C and D, Unenhanced (C) and enhanced (D) T1-weighted images (572/20) show findings similar in morphology but with borders better defined than on sonography. Enhanced image also defines avascular lesion with marked rim enhancement of borders. Lesion does not bulge upper pole of testis, and even this upper hemisphere seems smaller than rest of testicular parenchyma (arrowheads). Despite this finding and negative tumoral markers, lesion could not be differentiated from tumor, and patient underwent orchiectomy. Pathologic result was segmental testicular infarction. C 1590 JR:184, May 2005

5 Radiology of Testicular Infarction Fig year-old man with hemorrhagic segmental testicular infarction in right testicle. Patient was treated for acute scrotum and suspicion of spermatic cord torsion., MR sagittal T1-weighted unenhanced image shows high-signal-intensity foci in lesion due to hemorrhage (arrowhead)., Sagittal enhanced T1-weighted image shows avascular lesion, enhancement in periphery, and triangular shape (arrow). C, Hemorrhagic segmental testicular infarction has heterogeneous signal intensity on coronal T2-weighted image (arrow). D and E, MR coronal T2-weighted images initially (D) and 1 month later (E) show subtle retraction on tunica albuginea (arrowheads) in area close to segmental testicular infarction. This finding was also seen in three other patients who had chronic evolution of segmental testicular infarction. D be fixed via orchiopexy. One year later, a routine sonography examination showed a segmental infarction in the upper pole of the right testicle. This possible association with the bell-clapper anomaly must be noted because of the probability that disorders in maturation of the testicular parenchyma and the testicular vessels may lead to a segmental infarction, particularly in the testis with a greater possibility of intrascrotal movement. The testicular artery passes through the inguinal ring and gives off two branches near the testis (the anterior epididymal artery and the posterior epididymal artery). fter penetrating the tunica albuginea, the testicular artery, now called the capsular artery, forms branches off each lobule (centripetal arteries) that run into the septula testis toward the rete testis. The deferens artery, because it usually anastomoses with the posterior epididymal artery, provides a second source of blood to the testis. Thus, if the arterial flow is impaired because of abnormalities in the centripetal arteries or in the division of the testicular artery or because of an inconstant anterior epididymal artery, predisposition to a partial infarct will result, particularly when there are no significant collateral vessels supplying one or several testicular lobules (Fig. 6). This point of view may also explain why, in more than 80% of the patients in our series, the infarction was in the upper hemisphere of the testis, where vascularization of the internal testicular artery or superior centripetal vessels could be more precarious. Moreover, this hypothesis should explain the wedge shape of the lesion and the clinical presentation of acute scrotum in many patients. This study may have had some biases; first, the series was small, without a comparison C E JR:184, May

6 Fernández-Pérez et al. with other scrotal abnormalities such as testicular tumor and, particularly, infarcted tumor, which could show similar findings. However, we have tried to describe the most important characteristics that we have observed for segmental testicular infarction, remarking on the usefulness of MRI. Cases in which the lesion is round must be carefully assessed to avoid confusion with a nonvascular tumor. This situation, occurring in only two patients, was the least frequent in our series, but orchiectomy was needed to totally exclude a hypovascular or infarcted tumor. nother limitation was the inclusion criterion by which segmental testicular infarction was first suspected on sonography and then studied with MRI, limiting falsepositive or false-negative results. lso, the final diagnosis of segmental testicular infarction in those patients who did not undergo surgery may have caused a bias in patient selection because the method of study was known when our series of patients was selected. follow-up period of 6 months was established in consensus with a urologist. We believe that the possibility that a slow-growing tumor may have been underestimated is low because we observed none that not only grew but also changed in morphology and vascularity. Probably, new studies with more numerous cases will be necessary to confirm the results of this study, especially in comparison with other scrotal diseases. In conclusion, despite the infrequency of segmental testicular infarction, the radiologist plays a major role in its diagnosis to avoid orchiectomy. Segmental testicular infarction occurs in Fig. 5. Images of 32-year-old man with small segmental infarction in lower pole of right testis (arrows)., Coronal T2-weighted image shows segmental testicular infarction with low signal intensity and triangular shape., Coronal T1-weighted enhanced image shows typical enhancement of borders. Center of lesion lacks contrast enhancement, indicating avascular zone. C, Morphology is also observed in sonography study. D, In this patient, segmental testicular infarction was suspected, but he was one of the first patients studied and orchiectomy was performed because of our inexperience with this disorder. slight tunica albuginea retraction is seen in lesion periphery (arrowhead). C D 1592 JR:184, May 2005

7 Radiology of Testicular Infarction Fig. 6. Diagrammatic representation of testicular blood supply. If anterior epididymal artery (dotted line) is absent or its flow is impaired (e.g., because of excessive intrascrotal movement of testis, torsion and detorsion, unobserved interruption of arterial blood flow during operations performed on spermatic cord within inguinal canal), then capsular artery will be terminal vessel in upper pole of testis and is not supplied by collaterals. This possibility may make the patient prone to a focal infarct. a = artery. the third decade of life, and the patient usually is referred because of testicular pain and, frequently, acute scrotum. Color Doppler sonography creates the first diagnostic suspicion by showing a flowless wedge-shaped lesion. If the borders are not well defined or the findings are not conclusive, MRI is excellent for establishing the diagnosis, occasionally showing a hemorrhagic signal and an enhanced halo delimiting the avascular area. These data, together with the negative tumoral markers and short follow-up, should allow confidence in the diagnosis, thus avoiding orchiectomy. Only a few cases that are unclear because of a round morphology or nonconclusive MRI findings may require surgery and possible partial orchiectomy. References 1. Costa M, Calleja R, all RY, urgess N. Segmental testicular infarction. JU Int 1999;83: ird K, Rosenfield T. Testicular infarction secondary to acute inflammatory disease: demonstration by -scan ultrasound. Radiology 1984;152: Gofrit ON, Rund D, Shapiro, Pappo O, Landau EH, Pode D. Segmental testicular infarction due to sickle cell disease. J Urol 1998;160: aer HM, Gerber WL, Kendall R, Locke JL, Putong P. Segmental infarct of the testis due to hypersensitivity angiitis. J Urol 1989;142: Penson DF, ronson WJ. Segmental testicular infarction in the neonate: a case report. J Urol 1995;153: Shapiro SR, Rabinovitz J, Konrad P, Tesluk H. Focal infarction of the testicle in a child simulating testicular tumor. J Urol 1977;118: Lopez-Milena G, Medina-enitez, Ortega-Herrera R, Rabaza-Espigares J, Romero-Manjon MI, Hernandez-bad MJ. Usefulness of Doppler-color ultrasonography and identification of resistance indexes as early indicators of testicular infarction secondary to orchiepididymitis [in Spanish]. ctas Urol Esp 2000;24: Kramolowsky EV, eauchamp R, Milby WP. Color Doppler ultrasound for the diagnosis of segmental testicular infarction. J Urol 1993;150: Napoli V, Rapicano V, artolini M. Segmental ischemic testicular infarct: the echographic and histological correlations [in Italian]. Radiol Med (Torino) 1989;78: Sriprasad S, Kooiman GG, Muir GH, Sidhu PS. cute segmental testicular infarction: differentiation from tumour using high frequency colour Doppler ultrasound. r J Radiol 2001;74: Doebler RW, Norbut M. Localized testicular infarction masquerading as a testicular neoplasm. Urology 1999;54: Medina-Perez M, Sanchez-Gonzalez M. Testicular infarct simulating a neoplasms [in Spanish]. rch Esp Urol 1998;51: Fernandez-Gomez JM, Martin-Huescar, Rabade-Rey J, et al. Testicular infarction as a cause of benign intrascrotal tumor [in Spanish]. rch Esp Urol 1996;49: Flanagan JJ, Fowler RC. Testicular infarction mimicking tumour on scrotal ultrasound: a potential pitfall. Clin Radiol 1995;50: Pellice C Jr, Castella J, lert E, Cosme M, Comas S. Focal infarction of the testis: report of a case simulating a gonadal mass [in Spanish]. ctas Urol Esp 1995;19: Han DP, Dmochowski RR, lasser MH, uman JR. Segmental infarction of the testicle: atypical presentation of a testicular mass. J Urol 1994;151: Kodama K, Yotsuyanagi S, Fuse H, Hirano S, Kitagawa K, Masuda S. Magnetic resonance imaging to diagnose segmental testicular infarction J Urol 2000;163: Ruibal M, Quintana JL, Fernandez G, Zungri E. Segmental testicular infarction. J Urol 2003;170: aratelli GM, Vischi S, Mandelli PG, Gambetta GL, Visetti F, Sala E. Segmental hemorrhagic infarction of testicle. J Urol 1996;156: Chin SC, Wu CJ, Chen, Hsiao HS. Segmental hemorrhagic infarction of testis associated with epididymitis. J Clin Ultrasound 1998;26: Sentilhes L, Dunet F, Thoumas D, Khalaf, Grise P, Pfister C. Segmental testicular infarction: diagnosis and strategy. Can J Urol 2002;9: Ledwidge ME, Lee DK, Winter TC, Uehling DT, Mitchell CC, Lee FT. Sonographic diagnosis of superior hemispheric testicular infarction. JR 2002;179: Dogra V. ell-clapper deformity. (letter) JR 2003;180: JR:184, May