Ultrasound Obstet Gynecol 2008; 31: 588–591 Published online in Wiley InterScience (www.interscience.wiley.com).
Letters to the Editor
Prenatal diagnosis of enlarged prostatic utricle by ultrasonography and magnetic resonance imaging The prostatic utricle (PU) is a rudimentary structure present in the male prostatic urethra at the level of the verumontanum (colliculus seminalis). It is thought to be of mixed origin, with its cranial portion derived ¨ from the Mullerian duct and the caudal segment from the Wolffian duct and urogenital sinus. The classical description of an enlarged PU is a congenital dilated fluid-filled cavity posterior to the prostatic urethra, which may be detected in 11–14% of male infants with hypospadias and in 16.6% of boys presenting with intersex abnormalities and cryptorchidism1,2 . The most prominent complications consist of recurrent urinary infection and obstruction, stone formation in the pouch, dysuria, back-pressure changes and pseudo-incontinence due to secondary trapping of urine in the pouch, and occasionally xanthogranulomatosis or malignant degeneration. To our knowledge only two cases have been reported in which enlarged PU was described prenatally, but in these cases the identification of the cystic lesion as an enlarged PU was not made until laparotomy was performed3,4 . We present two cases of enlarged PU diagnosed prenatally by magnetic resonance imaging (MRI) in the first case and by sonography in the second case. After detection of a multicystic kidney in the fetus of a 27-year-old woman, gravida 3 para 2, at 22 weeks’ gestation, a hypoechoic structure appeared at the pelvic level at 32 weeks’ gestation with an intermediary location between the anterior bladder and posterior rectum. The suspected diagnosis on ultrasound examination of anterior meningocele or presacral teratoma was changed to PU enlargement by MRI, which showed an upward displacement of the urinary bladder by a diverticular structure ending in the urethra (Figure 1). The neonatal course was unremarkable, with spontaneous micturition, presence of normal external genitalia, and absence of bladder enlargement and of rectal mass. However, voiding cystography showed posterior bladder compression without reflux. After discharge with prescription of urinary antibiotics, the infant was re-evaluated at 4 months. On ultrasound examination, the PU was markedly enlarged (40 mm in maximal diameter) and compressed the bladder. The left kidney was non-functional on dimercaptosuccinic acid (DMSA) scintigraphy. The PU was then removed through a transvesical approach and a left nephrectomy performed at the same time. There were no postoperative complications. The second case was detected in a primigravida at 23 weeks’ gestation, after an ultrasound morphological assessment of the fetus showed bilateral megaureter and
Copyright 2008 ISUOG. Published by John Wiley & Sons, Ltd.
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Figure 1 Case 1. Prenatal sagittal magnetic resonance image showing enlarged prostatic utricle (PU).
a retrovesicular cystic structure measuring 30 by 12 mm which appeared to connect with the bladder neck via a fistula (Figure 2a). In the neonatal period an anterior mass was palpated on digital rectal examination and an enlarged PU was confirmed by postnatal ultrasound and uro-MRI (Figure 2b). At the first surgical procedure, through a transvesical approach, it was found that the right ureter was in fact connected to the PU. Therefore a right ureterostomy was performed along with the PU resection. One year later a right–left ureteroureterostomy and left ureterovesicular reimplantation into a psoic bladder were performed with an uneventful follow-up. There is a critical embryological period between 8 and 10 weeks, when a decline or delay in the hormonal output of the fetal testes can produce the combination of an enlarged PU, resulting from incomplete ¨ ¨ regression of the Mullerian ducts by lack of antimullerian hormone (AMH), and of hypospadias and intersex due to incomplete masculinization of the urogenital sinus. Exogenous female sex hormones, such as diethylstilbestrol acting transplacentally, might also interfere with the action of AMH and result in persistence of all or part ¨ of the Mullerian ducts in the male fetus5 . Both of our cases were associated with urinary anomalies, an association that has been reported to reach 10% and that implies a simultaneous disturbance of the urogenital tract, due to an abnormal induction of metanephric blastema by the ureteral bud6 . Prenatal sonographic diagnosis of an enlarged PU must be considered after the detection of a retrovesicular cystic mass in a male
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References
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1. Devine CJ, Gonzalez-Serva L, Stecker JF, Devine PC, Horton CE. Utricular configuration in hypospadias and intersex. J Urol 1980; 123: 407–411. ¨ upamuk¸ ¨ ¨ 2. Cift¸ci AO, Senocak ME, Buy cu N, Hi¸csonmez A. Abnormal prostatic utricle configuration in hypospadias and intersex patients. Eur J Pediatr Surg 1999; 9: 167–172. 3. Johal NS, Kraklau D, Deniz K, Mushtaq I. An unusual case of a prenatally detected large mullerian duct remnant. Pediatr Surg Int 2005; 21: 764–766. 4. Varlet F, Coupris L, Laumonier F, Duverne C. Congenital dilatation of the prostatic utricle. Embryologic review, diagnosis and treatment. A propos of 2 pseudo-tumoral cases, without hypospadias. Ann Urol (Paris) 1992; 26: 39–48. 5. Driscoll SG. Taylor SH. Effects of prenatal maternal estrogen on the male urogenital system. Obstet Gynecol 1980; 56: 537–542. ¨ 6. Schuhrke TD, Kaplan GW. Prostatic utricle cysts (mullerian duct cysts). J Urol 1978; 119: 765–767.
Distended azygos and hemiazygos vein without interrupted inferior vena cava in a case of agenesis of the ductus venosus A 26-year-old woman, gravida 2 para 0, was referred for a detailed scan including uterine artery Doppler ultrasound examination, as her previous pregnancy ended in the intrauterine death of twins. Uteroplacental resistance in the index pregnancy was markedly increased with bilateral notching of the uterine artery waveform. At 26 weeks detailed fetal echocardiography showed normal cardiac structures. However, a blood vessel with venous flow velocity waveforms running in parallel to the thoracic aorta, which was classified as a distended azygos vein, was detected by color Doppler ultrasound imaging (Figure 1). The possibility of a heterotaxy syndrome could be excluded due to situs solitus and a non-interrupted inferior vena cava (IVC) (Figures 2–4). Furthermore, abnormal draining of the umbilical vein (UV) directly into the abdominal part of the IVC was detected (Figures 3
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Figure 2 Case 2. Prenatal ultrasound (a) and postnatal magnetic resonance (b) images in the sagittal view showing enlarged protastic utricle (PU).
fetus, particularly when associated with hypospadias or urinary abnormalities, and should be further investigated using MRI. C. le Vaillant†, G. Podevin‡, M. P. Quere§, C. Talmant†, Y. Heloury‡ and G. Boog*† Departments of †Obstetrics and Gynecology, ‡Pediatric Surgery and §Pediatric Radiology, University of Nantes, 38, boulevard Jean Monnet, 44093 Nantes Cedex, France *Correspondence. (e-mail:
[email protected]) DOI: 10.1002/uog.5340
Copyright 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Figure 1 Color Doppler ultrasound examination showing distended azygos vein (red) posterior to the thoracic aorta (blue).
Ultrasound Obstet Gynecol 2008; 31: 588–591.
