K.E.M.
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Department of Radiology
Seth G.S. Medical College and K.E.M. Hospital, Mumbai , India
Case of the Month
Case of the Month
Clinical Profile:
Clinical Profile:
A 23-year-old man presented with the complaints of intermittent episodes of suprapubic discomfort for six months
A 23-year-old man presented with the complaints of intermittent episodes of suprapubic discomfort for six months
Radiological findings:
Radiological findings:
Ultrasonogram of the abdomen and pelvis (Fig 1) shows a ballooned right seminal vesicle. The right ureter is dilated. It inserts ectopically into the dilated right seminal vesicle. Proximally it is blind ending. The right kidney is absent. Both epididymis and testes are normal.
Ultrasonogram of the abdomen and pelvis (Fig 1) shows a ballooned right seminal vesicle. The right ureter is dilated. It inserts ectopically into the dilated right seminal vesicle. Proximally it is blind ending. The right kidney is absent. Both epididymis and testes are normal.
Fig. 1 Transabdominal ultrasonogram of abdomen and pelvis
Fig 1a: Axial section of the pelvis shows cystic dilatation of the right seminal vesicle with dependent echogenic content.
Fig 1b : Right parasagittal section of the lower abdomen and pelvis shows dilated and tortuous distal right ureter terminating into the ballooned right seminal vesicle.
Fig 1c : Panoramic view of the right parasagittal section of the abdomen and pelvis shows dilated and tortuous blind ending right ureter terminating into the right seminal vesicle.
Fig 1d : Oblique section in the right hypochondriac region shows empty right renal fossa.
CT Urography (Fig 2) shows the right kidney to be absent. The right seminal vesicle shows cystic dilatation. The right ureter opens into the right seminal vesicle. The left kidney and ureter are normal. The left seminal vesicle and prostate are normal.
CT Urography (Fig 2) shows the right kidney to be absent. The right seminal vesicle shows cystic dilatation. The right ureter opens into the right seminal vesicle. The left kidney and ureter are normal. The left seminal vesicle and prostate are normal.
Fig. 2 : CT Urography
Fig 2a: Axial section of the abdomen and pelvis in the venous phases shows a homogeneous, nonenhancing, cystic structure in the retrovesical, periprostatic, right paramedian region. The right ureter opens into this cystic structure.
Fig 2b : Coronal section in the excretory phase does not show the right kidney. The left kidney and the left ureter are normal.
MRI abdomen (Fig 3) shows a cyst like structure replacing the right seminal vesicle. The right ureteric remnant in the pelvis opens ectopically into the right seminal vesicle. The left seminal vesicle, the left kidney and the left ureter are normal.
MRI abdomen (Fig 3) shows a cyst like structure replacing the right seminal vesicle. The right ureteric remnant in the pelvis opens ectopically into the right seminal vesicle. The left seminal vesicle, the left kidney and the left ureter are normal.
Fig. 3 : MRI Abdomen Sequential coronal sections of T2W sequence a show dilated and tortuous right ureter terminating into the dilated right seminal vesicle. Proximally it is blind ending, terminating at the level of upper border of L5 vertebral body.
Radiological diagnosis:
Radiological diagnosis:
Zinner's syndrome
Zinner's syndrome
Timeline:
Timeline:
Discussion
Discussion
Zinner's syndrome is characterized by the triad of ipsilateral ejaculatory duct obstruction, seminal vesicle cysts, and renal agenesis, described first by A. Zinner in 1914.
Zinner's syndrome is characterized by the triad of ipsilateral ejaculatory duct obstruction, seminal vesicle cysts, and renal agenesis, described first by A. Zinner in 1914.
Clinical features:
Clinical features:
The syndrome usually presents in the second and third decade of life (after the beginning of sexual activity), usually in the form of voiding manifestations such as dysuria, prostatism, urgency, painful ejaculation, hematospermia, perineal pain/discomfort, and sometimes infertility[1].
The syndrome usually presents in the second and third decade of life (after the beginning of sexual activity), usually in the form of voiding manifestations such as dysuria, prostatism, urgency, painful ejaculation, hematospermia, perineal pain/discomfort, and sometimes infertility[1].
The issue of infertility is of particular importance as up to 45% of males with Zinner syndrome suffer from infertility due to ejaculatory duct obstruction [2].
The issue of infertility is of particular importance as up to 45% of males with Zinner syndrome suffer from infertility due to ejaculatory duct obstruction [2].
Embryology:
Embryology:
The relation between seminal vesicle cysts and ipsilateral renal agenesis can be explained by their common embryological origin[3].
The relation between seminal vesicle cysts and ipsilateral renal agenesis can be explained by their common embryological origin[3].
Between the fourth and seventh weeks of embryogenesis, the ureteral bud originates from the dorsal aspect of the distal mesonephric duct and extends in a dorso cranial fashion to meet and induce differentiation of the metanephric blastema, which will form the adult definitive kidney. The mesonephric duct differentiates into the appendix of the epididymis, paradidymis, epididymis, vas deferens, ejaculatory duct, seminal vesicle, and hemitrigone[3].
Between the fourth and seventh weeks of embryogenesis, the ureteral bud originates from the dorsal aspect of the distal mesonephric duct and extends in a dorso cranial fashion to meet and induce differentiation of the metanephric blastema, which will form the adult definitive kidney. The mesonephric duct differentiates into the appendix of the epididymis, paradidymis, epididymis, vas deferens, ejaculatory duct, seminal vesicle, and hemitrigone[3].
The kidney’s development relies on the stimulation of the ureteric bud and mesonephric duct. The failure of the ipsilateral kidney, ureter, hemitrigone, and seminal vesicle are usually derived from the malfunction of the mesonephric duct. This will lead to ipsilateral renal agenesis or dysplasia. If the ureteral bud arises in a more cephalic position off the mesonephric duct, delayed absorption of the caudal mesonephric duct will result in the distal ureteral bud emptying into mesonephric duct derivatives, including the vas deferens, seminal vesicle, ejaculatory duct, or into the bladder neck and urethra[3].
The kidney’s development relies on the stimulation of the ureteric bud and mesonephric duct. The failure of the ipsilateral kidney, ureter, hemitrigone, and seminal vesicle are usually derived from the malfunction of the mesonephric duct. This will lead to ipsilateral renal agenesis or dysplasia. If the ureteral bud arises in a more cephalic position off the mesonephric duct, delayed absorption of the caudal mesonephric duct will result in the distal ureteral bud emptying into mesonephric duct derivatives, including the vas deferens, seminal vesicle, ejaculatory duct, or into the bladder neck and urethra[3].
Imaging features:
Imaging features:
Imaging enables accurate diagnosis of this rare anomaly of the genitourinary tract. On sonography, the ipsilateral kidney is absent, and the obstructed ejaculatory ducts are seen as anechoic structures in the pelvis, though hemorrhage or infection can produce internal low level echoes . CT is better than sonography, and CT findings are of a retrovesicular periprostatic cystic mass along with ipsilateral renal agenesis. [4]
Imaging enables accurate diagnosis of this rare anomaly of the genitourinary tract. On sonography, the ipsilateral kidney is absent, and the obstructed ejaculatory ducts are seen as anechoic structures in the pelvis, though hemorrhage or infection can produce internal low level echoes . CT is better than sonography, and CT findings are of a retrovesicular periprostatic cystic mass along with ipsilateral renal agenesis. [4]
Transrectal ultrasonography findings are those of an anechoic lesion or with the presence of internal echoes due to bleeding or infection, with a thick and irregular wall, occasionally with calcifications, in a rectoprostatic location. It provides more information about the wall of the cyst and its contents (its echogenicity and the presence or absence of loculi). It also guides the surgeon in case of transrectal resection of the cyst.
Transrectal ultrasonography findings are those of an anechoic lesion or with the presence of internal echoes due to bleeding or infection, with a thick and irregular wall, occasionally with calcifications, in a rectoprostatic location. It provides more information about the wall of the cyst and its contents (its echogenicity and the presence or absence of loculi). It also guides the surgeon in case of transrectal resection of the cyst.
MRI is the modality of choice for precise delineation of the anatomy of the male genital tract, for demonstrating the seminal vesicles and evaluating anomalies of the mesonephric duct and to differentiate the seminal vesicle cysts from other cystic pelvic masses . MR is excellent for delineation of prostate and seminal vesicles and confirming that the cystic periprostatic structures are indeed within the seminal vesicles. The characteristic periprostatic and paramedian location enables the accurate identification of the seminal vesicle cysts on MR, which appear hypointense or hyperintense on T1W depending on the presence of amount of protein content and hyperintense on T2W images . A convoluted tail-like connection of the cystic tubules to the seminal vesicle also pins the seminal vesicles as the site of origin. Cysts are rarely more than 5 cm in size, although giant cysts larger than 12 cm have been described and these can cause bowel and bladder obstruction. MR is superior to CT as it demonstrates the anatomic relations in the pelvis better and can identify the ectopic ureteric orifices, which are missed on CT[4].
MRI is the modality of choice for precise delineation of the anatomy of the male genital tract, for demonstrating the seminal vesicles and evaluating anomalies of the mesonephric duct and to differentiate the seminal vesicle cysts from other cystic pelvic masses . MR is excellent for delineation of prostate and seminal vesicles and confirming that the cystic periprostatic structures are indeed within the seminal vesicles. The characteristic periprostatic and paramedian location enables the accurate identification of the seminal vesicle cysts on MR, which appear hypointense or hyperintense on T1W depending on the presence of amount of protein content and hyperintense on T2W images . A convoluted tail-like connection of the cystic tubules to the seminal vesicle also pins the seminal vesicles as the site of origin. Cysts are rarely more than 5 cm in size, although giant cysts larger than 12 cm have been described and these can cause bowel and bladder obstruction. MR is superior to CT as it demonstrates the anatomic relations in the pelvis better and can identify the ectopic ureteric orifices, which are missed on CT[4].
Differential diagnosis:
Differential diagnosis:
Differential diagnosis should be made with other entities such as laterally located prostatic cysts, diverticulosis of the vas deferens, ectopic ureterocele, and abscesses.
Differential diagnosis should be made with other entities such as laterally located prostatic cysts, diverticulosis of the vas deferens, ectopic ureterocele, and abscesses.
Seminal vesicle cysts need to be differentiated from other pelvic cystic lesions such as Müllerian duct cysts or utricular cysts. Differentiation is based on the position of the cysts in relation to the bladder neck. Utricular cysts communicate with the urethra, whereas Müllerian duct cysts do not. Müllerian duct cysts have normal seminal vesicles and ejaculatory ducts; anatomically, they are based on the midline. Wolffian ducts cysts, which are present in Zinner syndrome, are located in the paramedian area[6]
Seminal vesicle cysts need to be differentiated from other pelvic cystic lesions such as Müllerian duct cysts or utricular cysts. Differentiation is based on the position of the cysts in relation to the bladder neck. Utricular cysts communicate with the urethra, whereas Müllerian duct cysts do not. Müllerian duct cysts have normal seminal vesicles and ejaculatory ducts; anatomically, they are based on the midline. Wolffian ducts cysts, which are present in Zinner syndrome, are located in the paramedian area[6]
Management:
Management:
Management is determined depending on the size of the cysts, the symptoms of the patient, and the existence of complications. The prognosis is generally good in most cases. Surgery is the mainstay of management in symptomatic patients who have failed conservative treatment, or if the cysts exceed 5 cm in size . In the case of asymptomatic patients, conservative treatment with antibiotics is recommended. It is also possible to perform minimally invasive procedures such as transrectal ultrasonography-guided cyst aspiration[7].
Management is determined depending on the size of the cysts, the symptoms of the patient, and the existence of complications. The prognosis is generally good in most cases. Surgery is the mainstay of management in symptomatic patients who have failed conservative treatment, or if the cysts exceed 5 cm in size . In the case of asymptomatic patients, conservative treatment with antibiotics is recommended. It is also possible to perform minimally invasive procedures such as transrectal ultrasonography-guided cyst aspiration[7].
References:
References:
1. Soliman AA, Alshukami AA, AlZuber WH. Zinner’s syndrome, radiological diagnosis for a rare syndrome with non-specific clinical presentation: Case report - egyptian journal of radiology and nuclear medicine [Internet]. Springer Berlin Heidelberg; 2020
1. Soliman AA, Alshukami AA, AlZuber WH. Zinner’s syndrome, radiological diagnosis for a rare syndrome with non-specific clinical presentation: Case report - egyptian journal of radiology and nuclear medicine [Internet]. Springer Berlin Heidelberg; 2020
2. Sada F, Cekaj E, Saraci B, Shazi O, Al-Madani A, Jahanian S, Nahar S, Musa J, Mamillo K, Musliu D, Ahadi M, Leniqi F, Agarwal T, Hyseni F, Vokshi V, Fink AB, Deepali F, Shatri J, Bexheti S. Challenging clinical presentation of Zinner syndrome. Radiol Case Rep. 2022 Nov 3;18(1):256-259. doi: 10.1016/j.radcr.2022.10.006. PMID: 36353249; PMCID: PMC9638726.
2. Sada F, Cekaj E, Saraci B, Shazi O, Al-Madani A, Jahanian S, Nahar S, Musa J, Mamillo K, Musliu D, Ahadi M, Leniqi F, Agarwal T, Hyseni F, Vokshi V, Fink AB, Deepali F, Shatri J, Bexheti S. Challenging clinical presentation of Zinner syndrome. Radiol Case Rep. 2022 Nov 3;18(1):256-259. doi: 10.1016/j.radcr.2022.10.006. PMID: 36353249; PMCID: PMC9638726.
3. Hevia Palacios M, Álvarez-Maestro M, Gómez Rivas J, Aguilera Bazan A, Martínez-Piñeiro L. Zinner syndrome with ectopic ureter emptying into seminal vesicle [Internet]. U.S. National Library of Medicine; 2021
3. Hevia Palacios M, Álvarez-Maestro M, Gómez Rivas J, Aguilera Bazan A, Martínez-Piñeiro L. Zinner syndrome with ectopic ureter emptying into seminal vesicle [Internet]. U.S. National Library of Medicine; 2021
4. Mehra S, Ranjan R, Garga UC. Zinner syndrome-a rare developmental anomaly of the mesonephric duct diagnosed on magnetic resonance imaging [Internet]. U.S. National Library of Medicine; 2016
4. Mehra S, Ranjan R, Garga UC. Zinner syndrome-a rare developmental anomaly of the mesonephric duct diagnosed on magnetic resonance imaging [Internet]. U.S. National Library of Medicine; 2016
5. Abakar D, Badi F-E, Sabiri M, El Manjra S, Lezar S, Essodegui F. Zinner syndrome [Internet]. U.S. National Library of Medicine; 2021
5. Abakar D, Badi F-E, Sabiri M, El Manjra S, Lezar S, Essodegui F. Zinner syndrome [Internet]. U.S. National Library of Medicine; 2021
6. Hofmann A, Vauth F, Roesch WH. Zinner syndrome and infertility─a literature review based on a clinical case. Int J Impot Res. 2021 Mar;33(2):191-195. doi: 10.1038/s41443-020-00360-0. Epub 2020 Nov 5. Erratum in: Int J Impot Res. 2022 Aug;34(5):509. PMID: 33149231; PMCID: PMC8490148.
6. Hofmann A, Vauth F, Roesch WH. Zinner syndrome and infertility─a literature review based on a clinical case. Int J Impot Res. 2021 Mar;33(2):191-195. doi: 10.1038/s41443-020-00360-0. Epub 2020 Nov 5. Erratum in: Int J Impot Res. 2022 Aug;34(5):509. PMID: 33149231; PMCID: PMC8490148.
7. Kumar S, G KI, Khalil-Khan A, Arul Pitchai ADP, Sathiamoorthy R, Raju E. Zinner syndrome [Internet]. U.S. National Library of Medicine; 2022
7. Kumar S, G KI, Khalil-Khan A, Arul Pitchai ADP, Sathiamoorthy R, Raju E. Zinner syndrome [Internet]. U.S. National Library of Medicine; 2022