Testicular Scanning: Clinical Experience With 72 Patients

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THE JOURNAL OF UROLOGY

Copyright© 1981 by The Williams & Wilkins Co.

TESTICULAR SCANNING: CLINICAL EXPERIENCE WITH 72 PATIENTS KEY H. STAGE, ROBERT SCHOENVOGEL AND SAM LEWIS From the Divisions of Urology and Nuclear Medicine, The University of Texas Health Science Center, Dallas, Texas

ABSTRACT

Testicular scanning with 99mtechnetium pertechnetate is a well established, useful and readily available technique for the rapid assessment of patients with scrotal pain. Its use allows accurate differentiation of testicular torsion from other entities, such as epididymo-orchitis, and, thus, obviates scrotal exploration in a large number of cases. We herein report our experience with 72 cases. Only 1 falsely positive scan was obtained in 15 patients thought to have torsion, this being secondary to an incarcerated hernia extending into the scrotum. Of the remaining 14 patients undergoing scrotal explorations for testicular torsion the scan was accurate in 100 per cent of the cases. Testicular scanning with 99 mtechnetium pertechnetate (99 mTc) is a well established, easily available and accurate technique used routinely at our institution to assist in the clinical evaluation of patients with scrotal pain. We report our experience with 72 patients during the last 18 months. MATERIALS AND METHODS

After an initial clinical assessment the patient is taken immediately to nuclear medicine. A gamma scintillation camera with a converging hole and low energy collimator is used to obtain a testicular scan with 10 me. 99 mTc pertechnetate injected via a peripheral vein. A flow study is made at 5-second intervals for 50 seconds. Three static studies then are made of 300,000 counts each. The entire procedure is completed in 20 to 25 minutes. Charts and scans were reviewed independently by the authors. CASE REPORTS

Case 1. A 19-year-old man had a recent onset of pain in the lower aspect of the left testicle. The patient had been treated for gonorrhea. Physical examination revealed a painful left testicle, with induration of the lower aspect of the testicle and tail of the epididymis. Urinalysis was unremarkable and the patient's temperature was 98F. A testicular scan revealed increased uptake to the inferior aspect of the left testicle, which was believed to be compatible with left epididymitis (fig. 1). The patient was given antibiotics and the scrotum was elevated. Followup revealed resolution of the left epididymis with no atrophy of the testicle. Case 2. A 24-year-old man was seen on March 1, 1978, complaining of left testicular pain. He was given antibiotics for left epididymitis, which failed to resolve. He was seen again on April 21, still complaining of left testicular pain. Urinalysis was unremarkable and the patient's temperature was 97.6F. Atesticular scan revealed increased uptake to a surrounding zone of tissue to the left testicle with a lucent center (fig. 2). The interpretation was missed torsion versus abscess. Scrotal exploration revealed a 360-degree internal rotated torsion of the left testicle, which was intravaginal. Orchiectomy was done and the pathological condition was found to be infarction of the testicle. An orchiopexy was done on the right side and convalescence was uneventful. Case 3. A 15-year-old boy had an acute onset ofleft testicular pain. Physical examination revealed a tender left testicle with a horizontal lie. Urinalysis was unremarkable and the patient's temperature was 98F. A testicular scan revealed decreased Accepted for publication May 16, 1980.

perfusion to the left testicle, consistent with recent torsion (fig. 3). On scrotal exploration the left testicle underwent detorsion spontaneously with the induction of anesthesia. The left testicle was viable and bilateral orchiopexy was done. Convalescence was uneventful. Case 4. A 15-year-old boy had recent onset of' bilateral testicular pain, the right side more so than the left. His temperature was 98F and urinalysis was not recorded. Physical examination revealed extreme pain on palpation of the right testicle and cord. A small right hydrocele was present. A testicular scan revealed decreased flow to the right testicle, possibly representing torsion (fig. 4). This also was believed to be compatible with a diffuse process overlying the right testicle, causing decreased counts to the right side. At operation an incarcerated right inguinal hernia was found. Convalescence was uneventful. Case 5. A 29-year-old man complained of testicular pain secondary to being kicked in the left testicle. Diagnosis was left testicular contusion and a scan was not obtained. He was seen 3 days later with continued pain in the left testicle. Urinalysis was not obtained and his temperature was lOOF. A testicular scan revealed increased uptake to the left testicle of an irregular nature, consistent with testicular rupture (fig. 5). At operation a left testicular rupture was found and an orchiectomy was done. Convalescence was unremarkable. RESULTS

The diagnosis in 48 cases was epididymitis or epididymoorchitis, based on clinical examination and testicular scan (table 1). Patients ranged in age from 8 to 60 years, with an average of 23.1 years. Of these 48 patients 27 were black, 16 were white and 5 were of Latin American descent. The primary presenting complaint in the majority of cases was pain, followed by swelling, trauma and nausea associated with vomiting. Fever, generally low grade, was noted in only 26 patients (54.2 per cent) at initial presentation and pyuria was present in only 22 of the 48 patients (45.8 per cent). The right side was involved in 17 cases (35 per cent), the left side was involved in 20 cases (42 per cent), bilateral involvement was found in 5 cases (10 per cent) and the remaining cases had no significant increased uptake, the studies being considered normal primarily in patients with orchialgia of unknown etiology. Four patients were explored despite the fact that the testicular scan indicated increased uptake consistent with epididymitis. In all 4 cases the surgical diagnosis was acute epididymitis. In 15 cases scrotal exploration was done for torsion, based on a testicular scan as well as the clinical presentation (table 2). Patients ranged in age from 12 to 40 years, with an average of

334

33,5 notes revealed a_nd natt1:!'e of torsion ir;_ 6 cases, Torsion 180 to 720 deg-rees. Torsion of the right testicle was in 3 cases and external in 2. The recorded torsion of the left testicle vvas internal. Our ovn'°"'""'°" with testicular scanning has yielded 9 patients with other clinical conditions. Pain was the primary presenting complaint, followed by mass, swelling and fever. Abscess was diagnosed increased uptake of nuclide on the affected side with a lucent center. Testicular trauma involving testicular rupture presented as increased uptake on the affected side secondary to hematoma. A testicular mass revealed a normal scan and a hydrocele of the cord was noted at operation. In 1 patient the scan was read as suspicious for torsion, manifesting decreased uptake on the affected side. This was shown at operation to represent a bowel loop overlying the testicle in an incar,., ~.-ated hernia. In a second case of incarcerated inguinal hernia the scan was interpreted as revealing bowel or fluid in the affected scrotal side.

FIG. 1. Testicular scan consistent with left epididymitis. Note wide band of increased uptake to left cord area and increased activity to lateral paratesticular area (arrowheads).

FIG. 3. Testicular scan consistent with recent torsion on left side. Note normal uptake to spermatic cord and testicle on right side (large arrowheads), with sharp cut-off of nuclide uptake on left proximal cord (small arrowhead). No perfusion exists distally to left cord and testicle.

FIG. 2. 'Testicular scan consistent with missed torsion versus abscess. Note central lucent area surrounded by increased activity on periphery, creating halo-like effect on left side (arrowhead). 21.9 yeaxs. This patient group was whites and 3 Latin Americans. The was pain, followed and nausea as,so,c1~tte,o_ with vomiting. Fever was in 3 patients (20 per cent) and urinalysis revealed pyuria in 4 patients (27 cent). The testicular scan was positive for torsion in all 2 cases. In l case early in our experience the scan was read as suspicious for torsion (case 4) but an incarcerated inguinal hernia was found at the operation. In the second case explored for torsion the scan was read as normal preoperatively and no evidence of torsion was noted at the operation. The scan finding of torsion in the remaining 13 cases was confirmed surgically. The scan showed the right side to be involved in 8 cases (53 per cent) and the left side in 5 (33 per cent). In the remaining 2 cases l was read as normal and the other revealed bilateral asymmetric uptake believed to be consistent with intermittent torsion. This patient was found at operation to have bilateral bell clapper deformity and orchiopexy was performed. A review of operative

Fw. 4. Testicular scan representing decreased nuclide uptake to right testicle (arrowhead). This was found to represent incarcerated inguinal hernia on right side at operation.

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STAGE, SCHOENVOGEL AND LEWIS

at the proper diagnosis. Pyuria, microscopic hematuria and urethral discharge, as well as prostatic tenderness, suggest epididymo-orchitis as the etiology of a painful testis but this can be unreliable, since in our series only 46 per cent of the patients with epididymitis presented with pyuria and only 60 per cent of the patients with torsion had normal urinalyses. Levy,3 and Perri and associates4 reported on their experience with the Doppler stethoscope to diagnose testicular torsion in small series. However, Nasrallah and associates reported a moderately high incidence of falsely negative examinations. 5 Sonography has been advocated as a means to evaluate the scrotal contents and, recently, Winston and associates reported on their results with 20 cases. 6 They concluded that sonography most clearly revealed chronic complications of an inflammatory nature, particularly abscess. They also reported that torsion was differentiated equally with testicular scan and sonography, and, in their experience, a radionuclide scan was more accurate in diagnosis of acute orchitis, particularly in the early stage of TABLE

FIG. 5. Testicular scan representing extensive irregular uptake of nuclide to left testicle (arrowheads) consistent with testicular rupture secondary to trauma.

1. Clinical profile of 48 patients with epididymitis No.(%)

Race: Black White Latin Urinalysis: Within normal limits Pyuria Unavailable Temperature: Normal Elevated Chief complaint: Pain Swelling Trauma Nausea Scan results: Increased uptake Normal Decreased

TABLE 2.

27 (56) 16 (33) 5 (10) 23 (48) 22 (46) 3 (6) 22 (46) 26 (54) 39 10 5 2

(81) (21) (10) (4)

44 (92) 3 (6) 1 (2)

Clinical profile of 15 patients with torsion No.(%)

FIG. 6. Testicular scan representing recent spontaneous detorsion on right side. Note sharp cut-off of nuclide to right proximal cord near external ring (arrowhead), unlike widened band of nuclide seen with inflammation. DISCUSSION

Classical clinical presentation of testicular torsion is well known to the clinician and has been well outlined by Williamson. 1 Symptomatology, such as a history of similar episode, pain, vomiting, urinary symptoms, a history of trauma and recent exercise, led the patient to seek medical attention. Physical findings, such as scrotal inflammation, transverse lie of the affected testis, fever, hydrocele and the presence or absence of the so-called Prehn's sign, often still leave the physician in a dilemma of whether scrotal exploration should be done. This decision must be made rapidly, as recently pointed out by Wright in his review of 56 cases of spermatic cord torsion. 2 Spermatogenic cells are damaged after 2 hours and are destroyed after 6 hours. Leydig cells are non-viable after 10 hours. Rapid assessment and definitive therapy are imperative. Other techniques exist to help the attending physician arrive

Race: Black White Latin Urinalysis: Within normal limits Pyuria Unavailable Temperature: Normal Elevated Chief complaint: Pain Swelling Trauma Nausea Scan results: Pos. Neg. Equivocal TABLE

8 (53) 4 (27) 3 (20) 9 (60) 4 (27) 2 (13) 12 (80) 3 (20) 14 4 1 1

(93) (27) (7) (7)

13 (87) 1 (7) 1 (7)

3. Comparison of testicular scan series to date

Reference Hahn and associates8 Datta and Mishkin' Mukerjee and associates 10 Hitch and associates 11 Riley and associates 12 Holder and associates 13 Current series

No. Pts.

Falsely Pos.

28 23 28 18 98 62 72

0 0 0 0 2 0

1

Falsely Neg. 2 3 0 2

1 6 (4)* 0

% Accu-

racy

92.8 86.9

100.0 88.9 94.0

90.0 98.6

* Patients with attempts to distinguish tumor versus non-tumor and surgical versus non-surgical mass.

337

TESTICULAR

with testicular involvement. Our been lirnited. Nadel and associates rP1nnnp,n experience with the testicular 7 scan in 1973, outlining the use of 99 mTc (sodium Their technique was based on the principle torsion of a testicle would appear avascular and an inflamed testicle would appear with increased reflecting decreased and increased nuclide uptake, respectively, on the testicular scan. Other reports in the literature mirror the clinical usefulness of the testicular scan in the patient with the acute scroturn. 8 - 12 It should be stressed that interpretation of a radionuclide testicular scan should only be made after careful clinical examination of the patient by the physician reading the scan. Possible sources of error in our experience can be made when the history and position of the patient are unknown to the interpreter. A particular source of error involves those patients with posteriorly located epididymides, whose uptake is partially blocked to the camera by the anterior testicle. Simple medial or lateral rotation of the testicle will make the diagnosis apparent in most cases while the patient is still under the camera. In short, a simple commitment to provide service to the clinician around the clock is necessary and is available at this institution. Certain patterns emerge in the interpretation of the testicular scan in our review of these cases. With the picture of epididymitis the scan shows up as an area of increased uptake of the affected side. Vve have noted the almost universal presence of increased uptake to the spermatic cord as well and this presents as a wide band of increased uptake to the distal vessels. The ipsilateral testicle appears identical to the affected testicle if orchitis is not present. Careful distinction must be made in this instance, since to the unexperienced interpreter the ipsilateral testicle may appear cool, owing to the increased uptake in the epididymis and cord, and a false diagnosis of torsion may be made. With epididyrno-orchitis the band-like pattern is seen to the cord and the epididymis shows increased uptake (fig. 1). However, the inflammation to the testicle with associated orchitis will show increased uptake to the affected testicle as well. Again, this must not be misinterpreted as decreased uptake to the contralateral side. The classic picture of testicular torsion on the scan is an area of increased uptake to the surrounding soft tissue with a central cool or lucent area (fig. 2). This creates a halo-like effect. The age of torsion affects the scan picture. An old torsion is difficult to distinguish from a testicular abscess and, indeed, the 2 may be related causally. The picture of missed torsion versus testicular abscess takes 24 to 48 hours to evolve. An acute torsion will appear as decreased perfusion seen on the flow study to the affected side. V-J e have noted an appearance not unlike ymitis on the static in a testicle that has undergone recent detorsion. This to the recently detorted of increased uptake to the (fig. 1). There is a cut-off of the near the external ring, which results in a A--"" """''(fig. 6). Over-interpretation of the scan must be avoided. In decreased may be seen with or any mass overlying the testicle that will affect attenuation of the isotope. An old hematoma and even hernia will cause the appearar,ce of decreased uptake, which must be distinguished from torsion (fig. 4). Testicular rupture is seen as an exquisitely hot, irregular area over the affected testicle (fig. 5) and can be distinguished

frorn r.~,..-h.-h,=,

mass in the testicle is unreliable ·\,vith and, in our experience, the scan has been useful in Dni,+rh,m,,tio epididymo-orchitis, trauma and torsion of recent or prolonged duration. Our results compare to other series (table 3). Careful attempts were made to document long-term followup of those patients thought to have inflammatory processes based on examination and scan. In many cases this was not possible because of the transient nature of many of our patients and it may be argued that our incidence of falsely negative scans may be higher then reported. Even so, our experience leads us to conclude that the testicular radionuclide scan is accurate, easily obtainable in most institutions, non-invasive and informative. We have found it to be especially useful in the equivocal cases and note only l falsely positive scan and no falsely negatives in >72 cases. The testicular scan helps obviate retrospectively an unnecessary scrotal operation, as well as lowers surgical and hospitalization costs by serving as an accurate diagnostic aid to the practicing clinician. REFERENCES 1. Williamson, R. C.: Torsion of the testis and allied conditions. Brit.

J. Surg., 63: 465, 1976. 2. Wright, J. E.: Torsion of the testis. Brit. J. Surg., 64: 274, 1977. 3. Levy, B. J.: The diagnosis of torsion of the testicle using the

Doppler ultrasonic stethoscope. J. Urol., 113: 63, 1975. 4. Perri, A. J., Slachta, G. A., Feldman, A. E., Kendall, A. R. and

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Karafin, L .. The Doppler stethoscope and the diagnosis of the acute scrotum. J. Urol., 116: 598, 1976. Nasrallah, P. F., Manzone, D. and King, L. R.: Falsely negative Doppler examinations in testicular torsion. J. Ural., 118: 194, 1977. Winston, M. A., Handler, S. J. and Pritchard, J. H.: Ultrasonography of the testis-correlation with radiotracer perfusion. J. Nucl. Med., l!l: 615, 1978. Nadel, N. S., Gitter, M. H., Hahn, L. C. and Vernon, A. R.: Preoperative diagnosis of testicular torsion. Urology, 1: 48, 1973. Hahn, L. C., Nadel, N. S., Gitter, M. H. and Vernon, A. R.: Testicular scanning: a new modality for the preoperative diagnosis of testicular torsion. J. Urol., 113: 60, 1975. Datta, N. S. and Mishkin, F. S.: Radionuclide imaging in intrascrotal lesions. J.A.M.A., 231: 1060, 1975. !v'!ukerjee, M. G., Vollero, R. A., Mittemeyer, B. T. and Borski, A. A.: Diagnostic value of 99mTc in scrotal scan. Urology, 6: 453, 1975. Hitch, D. C., Gilday, D. L., Shand.ling, B. and Savage, J. P.: A new approach to the diagnosis of testicular torsion. J. Ped. Surg., 11: 537, 1976. T. W., Mosbaugh, P. G., Coles, J. L., Newman, D. M., Van E. D. and Heck, L. L.: Use of radioisotope scan in evaluation of intrascrotal lesions. J. Ural., 116: 472, 1976. Holder, L. E., Ivlartire, J. R., Holmes, E. R. and Wagner, H. N., Jr.: Testicular radionuclide angiography and static imaging: anatomy, scintig:raphic interpretaticn, and clinical indications. Radiology, 125: 739, 1977.

EDITORIAL COivIMENT Radionuclide imaging is best when used in direct consultation with the primary physician. With more subtle procedures such a team approach becomes a necessity. Examination of testicular scan images and the comments in this article nicely indicate this concept. Gerald Johnston Isotope Division National Institutes of Health Bethesda, Maryland