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Automated water-path ultrasonic examination of scrotum
AUTOMATED
WATER-PATH
ULTRASONIC
EXAMINATION
OF SCROTUM
PETER
M.D.
JOHN
C. WILSON, R. VALVO,
RAYMOND IRWIN
M.D.
GRAMIAK,
N. FRANK,
M.D.
M.D.
From the Department of Radiology, and the Division of Urology, The University of Rochester Medical Center, Rochester, New York
ABSTRACT -A new method of examining the scrotum by ultrasound with an automated waterpath scanner is described. This method allows immobility of the scrotum in a more acceptable and painless way than in contact scanning methods. Panoramic scans of the entire scrotum and precision tomographic plane placement are advantages over conventional techniques. A description of normal scrotal anatomy includes the mediastinum of the testis, an important scrotal landmark. Representative cases of benign and malignant scrotal disease are presented to emphasize the utility of waterpath scanning.
Ultrasound has been shown to be a reliable and safe method for evaluation of the scrotal contents.‘e5 It is particularly useful in distinguishing testicular masses from extratesticular disorders and thus may prevent unnecessary exploration. The usual method of ultrasonic examination has been contact scanning with a conventional articulated arm scanner. 1-3,6-8 Scrotal immobilization has been obtained either by holding the scrotum with the examiners hand’-396*’ or by suspending the scrotum on a support device between the thighs. 58 Discomfort associated with some scrotal conditions may be considerably aggravated, and, because of the deformable nature of the scrotum and mobility of the testes, it is difficult to obtain panoramic views with this method; indeed it has been suggested that the best results are obtained by limited sector scans of each testis in turna Under these conditions, precision plane placement becomes extremely difficult. One group has attempted to overcome these limitations by applying a small water bath on
94
top of the supported scrotum,8 a method similar to that sometimes used in thyroid and eye scanning. More recently, a high frequency real-time device has been applied to testicular diagnosiss4 This provides excellent high resolution pictures of the testes but has a small field of view, which tends to limit its ability to display anatomic relationships of the scrotal contents, particularly in larger scrotal disorders. It is believed that the water-path method described herein overcomes the noted difficulties of the previously described methods by providing panoramic views of the scrotum and precisely placed tomographic planes without deforming the scrotum and with no discomfort to the patient. We found that the mediastinum testis is readily visualized in each testis in our gray-scale display. This is in contrast with the other scanning methods where users report that this structure is not visible.3”p’*8 Jellins and Barracloughs have reported using a water delay scanner for examining the scrotum. In their method the scrotum was
UROLOGY
/ JULY 1931 / VOLUME
XVIII, NUMBER
1
FIGURE 1. Normul appearances. (A) Transverse sonogram showing midlevel granular gray-scale texture to Fine the testis (T). Mediastinum testes is seen as strong echoes adjacent to edge of each testis (arrowheads). linear echoes (S) extending Ji-om mediastinum into testicular substance are sometimes seen, Epididymis (E) is seen as area of high level echoes adjacent to mediastinum. (B) Longitudinal sonogram of left testis from same extending from cranial to caudal pole of testis. Small amount patient (A) shows mediastinum testis (arrowhead) of fluid (F) is sometimes seen in tunica vaginalis. shaved and immersed in a water tank. They achieved similar results to those described herein, but again do not report visualization of the mediastinum testis. Material
and Methods
The water-path scanner used is the U.I. Octoson.” It has eight mechanically sectored transducers placed in a water tank. Ultrasonic energy reaches the target via a water-path so that there is no transducer contact, and thus no disturbance of the scrotum and its contents. The transducers are mounted on a rigid arm which can be rotated, tilted, and translated in the transverse and longitudinal directions, as well as elevated or lowered to control the distance from the transducers to the target. This last degree of motion permits centering of the organ of interest in the focal zone of the transducers. Compound scanning with all eight transducers takes about two seconds, less time with fewer transducers. Simple sector scans to evaluate ultrasonic trasmission better are also possible. All *Ausonics, Sydney, Australia.
UROLOGY
/
JULY 1981
/
VOLUME XVIII, NUMBER
1
movements of the transducer arm are under the control of a microprocessor to allow precise changes of the scanning plane in 1, 2, 5, and 20-mm. increments. Image recording is either by the open-shutter technique on instant processing film or by multiformat camera photography of the video output of the analog scan converter contained in the system. The patient lies prone with the scrotum on top of a large tank of water, separated from the water by a polyethelene membrane. The penis is placed superior to the scrotum along the anterior abdominal wall, and a generous amount of mineral oil is used to ensure good contact with the membrane. It is not necessary to shave the scrotum or otherwise prepare the patient for the examination. Longitudinal and transverse sections are taken through the scrotum at 5-mm. intervals usually, and occasionally at smaller intervals. The focal zones of the transducers used are placed in the scrotum to ensure excellent lateral and axial resolution. Tilted planes are often used in transverse scanning to obtain true cross-section or short axis scans of the testes. Both compound scanning and simple scanning are used as required. Four transducers
95
FIGURE 2. Multiloculated hydrocele. Transverse sonogram shows normal right testis (T) and large amounts of hydrocelejluid (Hy) with numerous septations (arrowheads).
FIGURE 3. Complicated inflammatory hydrocele. Transverse sonogram shows nwmul left testis (T), complicated hydrocele with fibrinous strands (arrowheads). heavy fibrin layer covering testis (awow), and thickened scrotal wall (*). Right testis is normal.
are usually used for compound scanning, but occasionally all eight transducers are used to display boundary echoes better. A typical examination of the entire scrotal contents in two planes takes approximately twenty minutes and is well tolerated by all patients. Results Normal appearances are depicted in Figure 1. The gray-scale texture of the testis is granular with echo amplitudes in the mid-range. The mediastinum testis is seen as an echogenic linear structure adjacent to the edge of the testis on one side. It runs from the cranial to the caudal pole and extends 5 to 8 mm. into the testicular substance. In 95 per cent of our cases the testes are oriented with the mediastinum in the dorsal two thirds of the organ, and most often it is situated in the three-o’clock or nine-o’clock position to indicate 90 degree internal or external rotation of the testis. Linear echoes extending from the mediastinum testis are sometimes seen, consistent with the septate structure of the testis. The tunica albuginea is not seen as a
96
separate structure except in some inflammatory conditions where it is thickened. The epididymis can be identified as an echogenic region running along the side of the testis adjacent to the mediastinum. The caput epididymis is larger than the body and tail and is usually seen capping the superior pole of the testis. Circular or linear areas of decreased reflectivity within the epididymis, 1 to 2 mm. in diameter, are commonly seen and probably represent the internal coiling of the vas deferens. The scrotal skin appears 3 to 4 mm. thick in the normal patient. A small amount of fluid is sometimes seen in the tunica vaginalis. Five cases have been selected to represent testicular, extratesticular, and mixed disorders. Case Abstracts Case 1 -
multiloculated
hydrocele
(Fig.
2)
A twenty-one-year-old man with congenital bilateral lymphedema of the lower limbs had undergone bilateral hydrocelectomy six years previously. He presented with bilateral large hydroceles without scrotal wall edema. The
UROLOGY
/ JULY 1981 / VOLUMEXVIII,NUMBER
1
FIGURE 4. Seminoma. Longitudinal reflectivity in upper pole.
section of right testis demonstrates
ll-mm.
muss (Tu) of decreased
FIGURE 5. Chot-iocarcinomu. This transverse section shows normal mediastinum testis (M) on right side and large lef intratesticular mass (Tu) which has destroyed left mediastinum.
testes could not be adequately palpated. Panoramic views of the large scrotum revealed the multiloculated nature of the hydrocele and identified both testes which appeared small but otherwise normal. Case 2 inflammatory drocele (Fig. 3)
communicating
hy-
A fourteen-year-old boy underwent appendectomy for acute nonperforated appendicitis. On the second postoperative day a painful and tender enlargement of the left scrotum developed. Fever and chills persisted despite antibiotic treatment. The scrotum transilluminated poorly, and the testes and epididymides could not be palpated adequately. Urinalysis was normal. Scrotal ultrasound revealed the presence of a complicated left hydrocele with linear strands within the hydrocele sac. The epididymis was normally oriented but appeared slightly thickened. There was apparent thickening of the tunica albuginea. The patient underwent left scrotal exploration which disclosed an inflammatory communicating hydrocele. There was a loose fibrin layer encasing a normal-appearing testis and epididymis,
UROLOGY
/ JULY 19‘31/ VOLUMEXVIII,NUMBER
1
with fibrous strands extending within the drocele sac, a type of “scrotal peritonitis.” Case 3 -
seminornu
of testes (Fig.
hy-
4)
A thirty-two-year-old man presented with a two-week history of mild scrotal discomfort and slight right testicular enlargement. Serum markers were not elevated. Ultrasound showed an 11-mm. spherical solid mass of decreased reflectivity within the upper pole. An area of fatty change adjacent to the tumor was present which was not visualized by ultrasound. Case 4 -
choriocarcinoma
of testis (Fig.
5)
A twenty-three-year-old man presented with a left testicular mass and hemoptysis. Chest x-ray film revealed numerous lung metastases. Serum beta-human chorionic gonadotropin (HCG) levels were elevated. Scrotal ultrasound showed an irregular solid mass 2 cm. in diameter in the left testis, destroying portions of the mediastinum testis and invading the testicular substance. The right testis appeared normal. Orchiectomy was performed, and the lesion proved to be a choriocarcinema. Mediastinal invasion was confirmed by the pathologist.
97
Spermutocele. This transverse scan shows c!y~ti(. .str-rrctrlrc f Sp 1 c~lo.~c~l~~ npplicd to rrp/tu‘ /to/c (!f FIGURE 6. right testis on same side as mediastinum (as seen in lower .swtiotl 1. Tl~ir~kcw~tl str-otal skit1 (at-rows 1. cjtrlat-gc,rl epididymis (E), and decreased reflectivity of right testis all .YIIggwt i nfla tnttw tot-y prouw, L(af‘t tc3ti.v .slf01~3 areas of increased reflectivity .suggesting later stage of sanw ~~rocc.v.~.or pwhapv areas of’it!fctwtiotl. Case 5 (Fig. 6)
epididymo-orchitis
and spermatocele
A forty-six-year-old alcoholic man was found to have an asymptomatic right scrotal mass measuring 2.5 by 2 by 4 cm. on clinical examination. It transilluminated and was thought clinically to represent a spermatocele. Ultrasound showed a cylindrical, cystic structure 4 cm. in length and 1.5 cm. in diameter. It was closely applied to the testis although separate from it, in the region of the superior portion of the mediastinum. The mediastinal echoes were relatively lost in the region of the mass. These findings indicate that the lesion was in the region of the ductuli efferentes and thus was likely to be a spermatocele. The mediastinum is presumably stretched around the inner wall of the spermatocele accounting for its nonvisualization in the area. In addition, the right epididymis was larger than usual, with several areas of decreased reflectivity about 5 mm. in diameter. The right testis was of generally decreased reflectivity compared to the left. The scrotal skin appeared thickened measuring 1 cm. These findings are consistent with epididymo-orchitis with spermatocele. A follow-up sonogram is planned to evaluate progress. Comment The panoramic views provided by this scanner without deformation of the scrotum allow a more total evaluation of the scrotal contents. The size, shape, and volume of a lesion are readily determined. Testicular disease is readily separated from extratesticular abnormalities. Testicular disease can be excluded confidently by scanning each testis in precisely parallel scanning planes at 5-mm. intervals. The images contain numerical indicators of the scanning
98
The machine is basically a compound scanner, d compound scanning with up to 8 transducers readily shows organ boundaries completely, as well as internal structure. It is for this reason that the multiple septa in Case 1 and the inflammatory strands in Case 2 are readily seen. This compound scanning feature is one of the reasons that the mediastinum testis is readily demonstrated with this method. Testicular tumors are recognized by a local change in testicular texture. The lesion may be homogenous or may have a complex pattern with multiple cystic spaces. The margins are often irregular. The affected testis may be enlarged by the lesion. Sound attenuation in the tumor is usually similar to that in normal testis. Inflammatory lesions of the testis usually involve the entire gland, but occasionally may be focal. In the acute phase the inflammatory lesion is of lower reflectivity than normal testis and the texture is homogenous. It is associated with inflammatory change elsewhere in the scrotum with enlargement of the epididymis, often with prominent internal areas of decreased reflectivity. The scrotal skin may be thickened. Irregular increased reflectivity areas within a testis have been described in infarction of the testis4’5 and may also occur in chronic inflammatory disease. A hydrocele is recognized as an anechoic space around the testis with increased transmission of sound. Linear echoes within the fluid and thickening of the tunica albuginea indicated an inflammatory hydrocele in one of our cases. Extratesticular masses are recognized because of their relationship to the testis. Spermatoceles are anechoic spaces, often cylindrical in shape, related to cranial end of mediastinum testis. an
UROLOGY
/
JULY 1981
/
VOLUME XVIII, NUMBER
1
The mediastinium testis is a fibrous band extending from the caudal to the cranial end of the testis arising from the adjacent tunica albuginea. From its front and sides, numerous imperfect septa are given off which divide the interior of the organ into a number of incomplete lobules. The mediastinum supports the vessels and ducts in their passage to and from the substance of the testis. lo Misken and Bain,’ using bistable equipment, were able to see a linear cluster of echoes within the echo-free testis by contact scanning in the long axis with the testis either internally or externally rotated. These were thought to originate from the region of the rete testis or mediHowever, in a later report, using astinum. gray-scale equipment, the rete testis was not well defined.7 Several other authors, using articulated arm scanners either in direct contact with the scrotal skin or with an intervening water-bath, have reported inability to differentiate the mediastinum testis from the testicular substance.3,4,8 To our knowledge, there has been no previous report of gray-scale visualization of the mediastinum testis. The fact that the automated water-path scanner, as used in our laboratory, allows regular display of this structure indicates that a more complete display of testicular anatomy is obtained by this method. We believe that the other scrotal structures and intrascrotal relationships are also better displayed. The factors responsible for this are the excellent immobilization and nondeformation afforded bv, the water-path method, together with panoramic compound scans and precision tomographic Diane Dlacement available with this scanner. The teites usually lie in either internal or external rotation, and this may aid in demonstration of the mediastinum testis; however, the structure is also seen with the testis oriented in the anatomic position. We have found the mediastinum testis to be important as a scrotal landmark. It identifies the position of the epididymis which is always adjacent to the mediastinum. Spermatoceles occur in the region of the ductuli efferentes and thus are always located in the region of the superior portion of the mediastinum testis.” Cystic structures occurring elsewhere are unlikely to be spermatoceles. The position of the mediastinum allows orientation of the testis which can be correlated with the position of small palpable masses. Although we have as yet no experience of this, it is possible that cases of
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/ JULY 1931
/
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acute torsion may show an abnormal ventral orientation of the mediastinum, and perhaps enlargement or amplitude change in the mediastinal echo due to vascular engorgement or edema. The choriocarcinoma in Case 4 was shown pathologically to have invaded the mediastinum testis, but not the epididymis. This corresponded well with ultrasonic appearances where the normal echogenic mediastinum was no longer visible, as it was replaced by the low reflectivity tumor. It is thus possible that local absence of the mediastinal echo might indicate a small tumor which would otherwise be unrecognized, particularly in those patients who present with metastatic disease and clinically normal testes. Mediastinal invasion carries a less favorable prognosis than a peripherally located tumor. ‘* Although correlation with surgical and pathologic findings has so far been excellent, the number of cases studied is not yet large enough to make any conclusions as to the accuracy of this technique compared with other ultrasonic methods. Rochester,
New York 14642 (DR. WILSON)
ACKNOWLEDCMENTS. To Dr. Charles A. Linke, Dr. Robert S. Davis, and Dr. Abraham T. K. Cockett for the use of their cases, Susan Mammosser for technical assistance, Luanne Palmer for clerical help, and Alyce Norder and John Groves for illustrations.
References 1. Shawker TH: B-mode ultrasonic evaluation of scrotal swellings, Radiology 118: 417 (1976). 2. Gottesman JE, Sample WF, Skinner DG, and Ehrlich RM: Diagnostic ultrasound in the evaluation of scrotal masses, J. Urol. 118~601(1977). 3. Sample WF, Gottesman JE, Skinner DG, and Ehrlich RM: Gray scale ultrasound of the scrotum, Radiology 127: 225 (1978). 4. Leopold GR, et al: High-resolution ultrasonography of scrotal pathology, ihid. 131: 719 (1979). 5. Phillips GN, Schneider M, Goodman JD. and Macchia RJ: Ultrasonic evaluation of the scrotum, Urol. Radiol. 1: 157 (1980). 6. Misken M, and Bain I: B-mode ultrasonic examination of the testes, J. Clin. Ultrasound”2: 307 (1974). 7. Miskin M, Buckspan M, and Bain J: Ultrasonographic examination of scrotal masses, J. Urol. 117: 185 (1977). 8. Naser V, Ikinger U, van Kaick G, and Schweigler M: Echographie des scrotums und de testes mit hilfe einer neuen untersuchungstechnik, Urologe A 18: 321 (1979). 9. Jellins J, and Barraclough BH: Ultrasonic imaging of the scrotum. Ultrasound in Medicine, New York, Plenum Press, 1978, vol. 4, 1,. 151. 10. Goss CM: Gray’s Anatomy. 29th ed., Philadelphia, Lea and Febiger, 1973, p. 1303. 11. Smith DR: General Uroloev. . 9th ed., Los Altos. Lange, ._ 1978, p. 468. 12. Mostofi FK, and Price EF: Tumors of the male genital system, in Atlasof Tumor Pathology, Washington, D.C., Washington Armed Forces Institute of Pathology, 1973, p. 76. II
99
WATER-PATH
ULTRASONIC
EXAMINATION
OF SCROTUM
PETER
M.D.
JOHN
C. WILSON, R. VALVO,
RAYMOND IRWIN
M.D.
GRAMIAK,
N. FRANK,
M.D.
M.D.
From the Department of Radiology, and the Division of Urology, The University of Rochester Medical Center, Rochester, New York
ABSTRACT -A new method of examining the scrotum by ultrasound with an automated waterpath scanner is described. This method allows immobility of the scrotum in a more acceptable and painless way than in contact scanning methods. Panoramic scans of the entire scrotum and precision tomographic plane placement are advantages over conventional techniques. A description of normal scrotal anatomy includes the mediastinum of the testis, an important scrotal landmark. Representative cases of benign and malignant scrotal disease are presented to emphasize the utility of waterpath scanning.
Ultrasound has been shown to be a reliable and safe method for evaluation of the scrotal contents.‘e5 It is particularly useful in distinguishing testicular masses from extratesticular disorders and thus may prevent unnecessary exploration. The usual method of ultrasonic examination has been contact scanning with a conventional articulated arm scanner. 1-3,6-8 Scrotal immobilization has been obtained either by holding the scrotum with the examiners hand’-396*’ or by suspending the scrotum on a support device between the thighs. 58 Discomfort associated with some scrotal conditions may be considerably aggravated, and, because of the deformable nature of the scrotum and mobility of the testes, it is difficult to obtain panoramic views with this method; indeed it has been suggested that the best results are obtained by limited sector scans of each testis in turna Under these conditions, precision plane placement becomes extremely difficult. One group has attempted to overcome these limitations by applying a small water bath on
94
top of the supported scrotum,8 a method similar to that sometimes used in thyroid and eye scanning. More recently, a high frequency real-time device has been applied to testicular diagnosiss4 This provides excellent high resolution pictures of the testes but has a small field of view, which tends to limit its ability to display anatomic relationships of the scrotal contents, particularly in larger scrotal disorders. It is believed that the water-path method described herein overcomes the noted difficulties of the previously described methods by providing panoramic views of the scrotum and precisely placed tomographic planes without deforming the scrotum and with no discomfort to the patient. We found that the mediastinum testis is readily visualized in each testis in our gray-scale display. This is in contrast with the other scanning methods where users report that this structure is not visible.3”p’*8 Jellins and Barracloughs have reported using a water delay scanner for examining the scrotum. In their method the scrotum was
UROLOGY
/ JULY 1931 / VOLUME
XVIII, NUMBER
1
FIGURE 1. Normul appearances. (A) Transverse sonogram showing midlevel granular gray-scale texture to Fine the testis (T). Mediastinum testes is seen as strong echoes adjacent to edge of each testis (arrowheads). linear echoes (S) extending Ji-om mediastinum into testicular substance are sometimes seen, Epididymis (E) is seen as area of high level echoes adjacent to mediastinum. (B) Longitudinal sonogram of left testis from same extending from cranial to caudal pole of testis. Small amount patient (A) shows mediastinum testis (arrowhead) of fluid (F) is sometimes seen in tunica vaginalis. shaved and immersed in a water tank. They achieved similar results to those described herein, but again do not report visualization of the mediastinum testis. Material
and Methods
The water-path scanner used is the U.I. Octoson.” It has eight mechanically sectored transducers placed in a water tank. Ultrasonic energy reaches the target via a water-path so that there is no transducer contact, and thus no disturbance of the scrotum and its contents. The transducers are mounted on a rigid arm which can be rotated, tilted, and translated in the transverse and longitudinal directions, as well as elevated or lowered to control the distance from the transducers to the target. This last degree of motion permits centering of the organ of interest in the focal zone of the transducers. Compound scanning with all eight transducers takes about two seconds, less time with fewer transducers. Simple sector scans to evaluate ultrasonic trasmission better are also possible. All *Ausonics, Sydney, Australia.
UROLOGY
/
JULY 1981
/
VOLUME XVIII, NUMBER
1
movements of the transducer arm are under the control of a microprocessor to allow precise changes of the scanning plane in 1, 2, 5, and 20-mm. increments. Image recording is either by the open-shutter technique on instant processing film or by multiformat camera photography of the video output of the analog scan converter contained in the system. The patient lies prone with the scrotum on top of a large tank of water, separated from the water by a polyethelene membrane. The penis is placed superior to the scrotum along the anterior abdominal wall, and a generous amount of mineral oil is used to ensure good contact with the membrane. It is not necessary to shave the scrotum or otherwise prepare the patient for the examination. Longitudinal and transverse sections are taken through the scrotum at 5-mm. intervals usually, and occasionally at smaller intervals. The focal zones of the transducers used are placed in the scrotum to ensure excellent lateral and axial resolution. Tilted planes are often used in transverse scanning to obtain true cross-section or short axis scans of the testes. Both compound scanning and simple scanning are used as required. Four transducers
95
FIGURE 2. Multiloculated hydrocele. Transverse sonogram shows normal right testis (T) and large amounts of hydrocelejluid (Hy) with numerous septations (arrowheads).
FIGURE 3. Complicated inflammatory hydrocele. Transverse sonogram shows nwmul left testis (T), complicated hydrocele with fibrinous strands (arrowheads). heavy fibrin layer covering testis (awow), and thickened scrotal wall (*). Right testis is normal.
are usually used for compound scanning, but occasionally all eight transducers are used to display boundary echoes better. A typical examination of the entire scrotal contents in two planes takes approximately twenty minutes and is well tolerated by all patients. Results Normal appearances are depicted in Figure 1. The gray-scale texture of the testis is granular with echo amplitudes in the mid-range. The mediastinum testis is seen as an echogenic linear structure adjacent to the edge of the testis on one side. It runs from the cranial to the caudal pole and extends 5 to 8 mm. into the testicular substance. In 95 per cent of our cases the testes are oriented with the mediastinum in the dorsal two thirds of the organ, and most often it is situated in the three-o’clock or nine-o’clock position to indicate 90 degree internal or external rotation of the testis. Linear echoes extending from the mediastinum testis are sometimes seen, consistent with the septate structure of the testis. The tunica albuginea is not seen as a
96
separate structure except in some inflammatory conditions where it is thickened. The epididymis can be identified as an echogenic region running along the side of the testis adjacent to the mediastinum. The caput epididymis is larger than the body and tail and is usually seen capping the superior pole of the testis. Circular or linear areas of decreased reflectivity within the epididymis, 1 to 2 mm. in diameter, are commonly seen and probably represent the internal coiling of the vas deferens. The scrotal skin appears 3 to 4 mm. thick in the normal patient. A small amount of fluid is sometimes seen in the tunica vaginalis. Five cases have been selected to represent testicular, extratesticular, and mixed disorders. Case Abstracts Case 1 -
multiloculated
hydrocele
(Fig.
2)
A twenty-one-year-old man with congenital bilateral lymphedema of the lower limbs had undergone bilateral hydrocelectomy six years previously. He presented with bilateral large hydroceles without scrotal wall edema. The
UROLOGY
/ JULY 1981 / VOLUMEXVIII,NUMBER
1
FIGURE 4. Seminoma. Longitudinal reflectivity in upper pole.
section of right testis demonstrates
ll-mm.
muss (Tu) of decreased
FIGURE 5. Chot-iocarcinomu. This transverse section shows normal mediastinum testis (M) on right side and large lef intratesticular mass (Tu) which has destroyed left mediastinum.
testes could not be adequately palpated. Panoramic views of the large scrotum revealed the multiloculated nature of the hydrocele and identified both testes which appeared small but otherwise normal. Case 2 inflammatory drocele (Fig. 3)
communicating
hy-
A fourteen-year-old boy underwent appendectomy for acute nonperforated appendicitis. On the second postoperative day a painful and tender enlargement of the left scrotum developed. Fever and chills persisted despite antibiotic treatment. The scrotum transilluminated poorly, and the testes and epididymides could not be palpated adequately. Urinalysis was normal. Scrotal ultrasound revealed the presence of a complicated left hydrocele with linear strands within the hydrocele sac. The epididymis was normally oriented but appeared slightly thickened. There was apparent thickening of the tunica albuginea. The patient underwent left scrotal exploration which disclosed an inflammatory communicating hydrocele. There was a loose fibrin layer encasing a normal-appearing testis and epididymis,
UROLOGY
/ JULY 19‘31/ VOLUMEXVIII,NUMBER
1
with fibrous strands extending within the drocele sac, a type of “scrotal peritonitis.” Case 3 -
seminornu
of testes (Fig.
hy-
4)
A thirty-two-year-old man presented with a two-week history of mild scrotal discomfort and slight right testicular enlargement. Serum markers were not elevated. Ultrasound showed an 11-mm. spherical solid mass of decreased reflectivity within the upper pole. An area of fatty change adjacent to the tumor was present which was not visualized by ultrasound. Case 4 -
choriocarcinoma
of testis (Fig.
5)
A twenty-three-year-old man presented with a left testicular mass and hemoptysis. Chest x-ray film revealed numerous lung metastases. Serum beta-human chorionic gonadotropin (HCG) levels were elevated. Scrotal ultrasound showed an irregular solid mass 2 cm. in diameter in the left testis, destroying portions of the mediastinum testis and invading the testicular substance. The right testis appeared normal. Orchiectomy was performed, and the lesion proved to be a choriocarcinema. Mediastinal invasion was confirmed by the pathologist.
97
Spermutocele. This transverse scan shows c!y~ti(. .str-rrctrlrc f Sp 1 c~lo.~c~l~~ npplicd to rrp/tu‘ /to/c (!f FIGURE 6. right testis on same side as mediastinum (as seen in lower .swtiotl 1. Tl~ir~kcw~tl str-otal skit1 (at-rows 1. cjtrlat-gc,rl epididymis (E), and decreased reflectivity of right testis all .YIIggwt i nfla tnttw tot-y prouw, L(af‘t tc3ti.v .slf01~3 areas of increased reflectivity .suggesting later stage of sanw ~~rocc.v.~.or pwhapv areas of’it!fctwtiotl. Case 5 (Fig. 6)
epididymo-orchitis
and spermatocele
A forty-six-year-old alcoholic man was found to have an asymptomatic right scrotal mass measuring 2.5 by 2 by 4 cm. on clinical examination. It transilluminated and was thought clinically to represent a spermatocele. Ultrasound showed a cylindrical, cystic structure 4 cm. in length and 1.5 cm. in diameter. It was closely applied to the testis although separate from it, in the region of the superior portion of the mediastinum. The mediastinal echoes were relatively lost in the region of the mass. These findings indicate that the lesion was in the region of the ductuli efferentes and thus was likely to be a spermatocele. The mediastinum is presumably stretched around the inner wall of the spermatocele accounting for its nonvisualization in the area. In addition, the right epididymis was larger than usual, with several areas of decreased reflectivity about 5 mm. in diameter. The right testis was of generally decreased reflectivity compared to the left. The scrotal skin appeared thickened measuring 1 cm. These findings are consistent with epididymo-orchitis with spermatocele. A follow-up sonogram is planned to evaluate progress. Comment The panoramic views provided by this scanner without deformation of the scrotum allow a more total evaluation of the scrotal contents. The size, shape, and volume of a lesion are readily determined. Testicular disease is readily separated from extratesticular abnormalities. Testicular disease can be excluded confidently by scanning each testis in precisely parallel scanning planes at 5-mm. intervals. The images contain numerical indicators of the scanning
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The machine is basically a compound scanner, d compound scanning with up to 8 transducers readily shows organ boundaries completely, as well as internal structure. It is for this reason that the multiple septa in Case 1 and the inflammatory strands in Case 2 are readily seen. This compound scanning feature is one of the reasons that the mediastinum testis is readily demonstrated with this method. Testicular tumors are recognized by a local change in testicular texture. The lesion may be homogenous or may have a complex pattern with multiple cystic spaces. The margins are often irregular. The affected testis may be enlarged by the lesion. Sound attenuation in the tumor is usually similar to that in normal testis. Inflammatory lesions of the testis usually involve the entire gland, but occasionally may be focal. In the acute phase the inflammatory lesion is of lower reflectivity than normal testis and the texture is homogenous. It is associated with inflammatory change elsewhere in the scrotum with enlargement of the epididymis, often with prominent internal areas of decreased reflectivity. The scrotal skin may be thickened. Irregular increased reflectivity areas within a testis have been described in infarction of the testis4’5 and may also occur in chronic inflammatory disease. A hydrocele is recognized as an anechoic space around the testis with increased transmission of sound. Linear echoes within the fluid and thickening of the tunica albuginea indicated an inflammatory hydrocele in one of our cases. Extratesticular masses are recognized because of their relationship to the testis. Spermatoceles are anechoic spaces, often cylindrical in shape, related to cranial end of mediastinum testis. an
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The mediastinium testis is a fibrous band extending from the caudal to the cranial end of the testis arising from the adjacent tunica albuginea. From its front and sides, numerous imperfect septa are given off which divide the interior of the organ into a number of incomplete lobules. The mediastinum supports the vessels and ducts in their passage to and from the substance of the testis. lo Misken and Bain,’ using bistable equipment, were able to see a linear cluster of echoes within the echo-free testis by contact scanning in the long axis with the testis either internally or externally rotated. These were thought to originate from the region of the rete testis or mediHowever, in a later report, using astinum. gray-scale equipment, the rete testis was not well defined.7 Several other authors, using articulated arm scanners either in direct contact with the scrotal skin or with an intervening water-bath, have reported inability to differentiate the mediastinum testis from the testicular substance.3,4,8 To our knowledge, there has been no previous report of gray-scale visualization of the mediastinum testis. The fact that the automated water-path scanner, as used in our laboratory, allows regular display of this structure indicates that a more complete display of testicular anatomy is obtained by this method. We believe that the other scrotal structures and intrascrotal relationships are also better displayed. The factors responsible for this are the excellent immobilization and nondeformation afforded bv, the water-path method, together with panoramic compound scans and precision tomographic Diane Dlacement available with this scanner. The teites usually lie in either internal or external rotation, and this may aid in demonstration of the mediastinum testis; however, the structure is also seen with the testis oriented in the anatomic position. We have found the mediastinum testis to be important as a scrotal landmark. It identifies the position of the epididymis which is always adjacent to the mediastinum. Spermatoceles occur in the region of the ductuli efferentes and thus are always located in the region of the superior portion of the mediastinum testis.” Cystic structures occurring elsewhere are unlikely to be spermatoceles. The position of the mediastinum allows orientation of the testis which can be correlated with the position of small palpable masses. Although we have as yet no experience of this, it is possible that cases of
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acute torsion may show an abnormal ventral orientation of the mediastinum, and perhaps enlargement or amplitude change in the mediastinal echo due to vascular engorgement or edema. The choriocarcinoma in Case 4 was shown pathologically to have invaded the mediastinum testis, but not the epididymis. This corresponded well with ultrasonic appearances where the normal echogenic mediastinum was no longer visible, as it was replaced by the low reflectivity tumor. It is thus possible that local absence of the mediastinal echo might indicate a small tumor which would otherwise be unrecognized, particularly in those patients who present with metastatic disease and clinically normal testes. Mediastinal invasion carries a less favorable prognosis than a peripherally located tumor. ‘* Although correlation with surgical and pathologic findings has so far been excellent, the number of cases studied is not yet large enough to make any conclusions as to the accuracy of this technique compared with other ultrasonic methods. Rochester,
New York 14642 (DR. WILSON)
ACKNOWLEDCMENTS. To Dr. Charles A. Linke, Dr. Robert S. Davis, and Dr. Abraham T. K. Cockett for the use of their cases, Susan Mammosser for technical assistance, Luanne Palmer for clerical help, and Alyce Norder and John Groves for illustrations.
References 1. Shawker TH: B-mode ultrasonic evaluation of scrotal swellings, Radiology 118: 417 (1976). 2. Gottesman JE, Sample WF, Skinner DG, and Ehrlich RM: Diagnostic ultrasound in the evaluation of scrotal masses, J. Urol. 118~601(1977). 3. Sample WF, Gottesman JE, Skinner DG, and Ehrlich RM: Gray scale ultrasound of the scrotum, Radiology 127: 225 (1978). 4. Leopold GR, et al: High-resolution ultrasonography of scrotal pathology, ihid. 131: 719 (1979). 5. Phillips GN, Schneider M, Goodman JD. and Macchia RJ: Ultrasonic evaluation of the scrotum, Urol. Radiol. 1: 157 (1980). 6. Misken M, and Bain I: B-mode ultrasonic examination of the testes, J. Clin. Ultrasound”2: 307 (1974). 7. Miskin M, Buckspan M, and Bain J: Ultrasonographic examination of scrotal masses, J. Urol. 117: 185 (1977). 8. Naser V, Ikinger U, van Kaick G, and Schweigler M: Echographie des scrotums und de testes mit hilfe einer neuen untersuchungstechnik, Urologe A 18: 321 (1979). 9. Jellins J, and Barraclough BH: Ultrasonic imaging of the scrotum. Ultrasound in Medicine, New York, Plenum Press, 1978, vol. 4, 1,. 151. 10. Goss CM: Gray’s Anatomy. 29th ed., Philadelphia, Lea and Febiger, 1973, p. 1303. 11. Smith DR: General Uroloev. . 9th ed., Los Altos. Lange, ._ 1978, p. 468. 12. Mostofi FK, and Price EF: Tumors of the male genital system, in Atlasof Tumor Pathology, Washington, D.C., Washington Armed Forces Institute of Pathology, 1973, p. 76. II
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