How embryology knowledge can help radiologists in the differential diagnosis of canal of Nuck pathologies.

The Canal of Nuck (CN) is an anatomical structure which is often forgotten. It is the female equivalent of the male processus vaginalis and corresponds to a protrusion of parietal peritoneum that extends from the inguinal canal to labia majora. Radiologists rarely encounter patients with pathology of CN, especially in adult population. It is well known that CN diseases can occur in paediatric patient (especially younger than 5 years of age) and they are associated to high morbidity (for example ovarian hernia with high risk of incarceration and torsion). The aim of our work is to review embryology, anatomy and pathologies of the CN thanks to a multi modal approach-ultrasound (US), Computed Tomography (CT) and Magnetic Resonance imaging (MRI)-to make radiologists more aware of such conditions and guarantee a prompt and correct diagnosis not only in paediatric patients but also in the adult population.

[Ultrasound of the fetal urinary system during the first trimester of pregnancy]. / Échographie de l'appareil urinaire fœtal au 1er trimestre de la grossesse.

The detection of abnormalities of the fetal urinary system in the first trimester of pregnancy is constantly improving, namely owing to the improved resolution of the image, the use of the endovaginal approach and thanks to sonographers' constant training. The pathological aspects, usually detected in the second trimester of pregnancy, can be suspected early in the first trimester and range from kidneys' cavity dilation to bilateral renal agenesis, polycystic kidney disease, multi-cystic dysplasia and bladder megavessia or bladder exstrophy. A poly-malformative syndrome is to be found out. The detection of an abnormality of the urinary tract requires a close ultrasound check. Very often, the pathological aspects tend to disappear spontaneously. In particular, the non-visualization of the bladder requires repeated examinations during the same session or even a little later in the pregnancy. We will carry out a review of the literature by pointing out the usual and unusual aspects of the fetal urinary system visible in the first trimester and we will as well propose an algorithm describing how to deal with abnormalities of the urinary tract that can be found out at first trimester ultrasound.

Are ultrasound renal aspects associated with urinary biochemistry in fetuses with lower urinary tract obstruction?

OBJECTIVE: To evaluate the association between ultrasonographic renal parameters and urine biochemistry in fetuses with lower urinary tract obstruction (LUTO). METHODS: Data were collected prospectively from 31 consecutive fetuses with LUTO that underwent vesicocentesis for fetal urinary biochemistry between April 2013 and September 2015. The following renal ultrasound markers were assessed immediately before the vesicocentesis: renal echogenicity, presence of cortical cysts, presence of findings suggestive of 'renal dysplasia' (hyperechogenic cystic kidneys with no cortical-medullary differentiation) and severe oligohydramnios (amniotic fluid < 5th percentile). The association of these parameters to the fetal urinary concentration of sodium, chloride, calcium, osmolality and beta2-microglobulin was investigated by logistic regression analysis. RESULTS: There was no relationship between any of the ultrasonographic fetal renal characteristics and fetal urinary biochemistry. CONCLUSIONS: In LUTO, the ultrasound appearance of the fetal kidneys and urinary biochemistry are not correlated. It may be better to take both ultrasound and biochemistry into account when evaluating fetuses with fetal LUTO. © 2016 John Wiley & Sons, Ltd.

Prenatal diagnosis and telemedicine consultation of fetal urologic disorders.

In Arkansas, telemedicine is used commonly in obstetrics through Antenatal and Neonatal Guidelines, Education and Learning System (ANGELS), the existing statewide telemedicine network. This network is used primarily for tele-ultrasound and maternal-fetal medicine consultation. This study is a retrospective case series, describing all the patients who had a prenatally diagnosed urologic anomaly that required prenatal urologic consultation. From 2009-2013, approximately 1300 anomalies were recorded in the Arkansas Fetal Diagnosis and Management (AFDM) database, 14% of which were urologic anomalies. Twenty-six cases required prenatal urologic consultation, 25 of which were conducted via telemedicine. Teleconsultation allowed patients to combine maternal-fetal medicine and urologic consultations in one visit, saving time and effort and ultimately, for most patients, providing reassurance that delivery could be accomplished locally with postnatal follow-up already arranged. While there are several studies reporting the use of telemedicine for various subspecialty consultations, to our knowledge, this is the first to describe the use of telemedicine for prenatal urology consultation. Future research could randomize patients prospectively to allow comparison of both the outcomes as well as the patient experience.

[Comparative analysis of interuterine therapy of unilateral and bilateral fetal obstructive uropathy]. / Analiza pórownawcza wyników terapii wewnatrzmacicznej obustronnej i jednostronnej uropatii zaporowej.

OBJECTIVE: The goal of the work was a comparative analysis of intrauterine therapy among pregnant women with diagnosed fetal uropathy and unilateral hydronephrosis. METHODS: The study was conducted on a group of 98 pregnant women hospitalized at the Department of Gynecology Fertility and Fetal Therapy Polish Mother's Memorial Hospital between 2006-2012. The study group included 77 cases of fetal obstructive uropathy (79%) and 21 cases of unilateral hydronephrosis (21%). Both groups have been analyzed in terms of prognosis. Follow-up has been conducted and results have been statistically analyzed. RESULTS: In 11% of cases of obstructive uropathy therapy early complications were observed. The remaining 89% of the patients delivered at a later date, of which 54% after 34 weeks of pregnancy The average weight of a newborn was 2645g and Apgar score - 7.45. 73% of newborns were discharged home in good condition, with preserved diuresis. CONCLUSIONS: 1. The use of intrauterine therapy has a positive effect on fetal condition and newborn postnatal state. 2. Unilateral hydronephrosis group was characterized by a significantly longer duration of pregnancy higher birth weight, Apgar score, and greater survival of newborns. 3. In the group of obstructive uropathy survival improvement was achieved and dieresis was preserved Intrauterine interventions were associated with a low risk of complications.

Urologic and anorectal complications of sacrococcygeal teratomas: prenatal and postnatal predictors.

PURPOSE: Anorectal and urologic sequelae are observed in long-term survivors of sacrococcygeal teratoma (SCT). In this study we evaluate the incidence and predictors of anorectal and urologic complications in SCT. METHODS: A retrospective review was performed for all SCT patients who underwent resection at a single institution between 2000 and 2012. Enrollment criteria included a minimum of 12months follow-up. Categorical variables were analyzed by Fisher's exact test and continuous variables by Mann Whitney test (p<0.05). RESULTS: Forty-five patients were studied. Anorectal complications occurred in 29%, including severe chronic constipation (n=13) and fecal incontinence (n=4). Urologic complications occurred in 33%, including neurogenic bladder (n=12), vesicoureteral reflux (n=5), and urinary incontinence (n=7). Prenatal imaging by fetal MRI demonstrated mass effect with obstruction of the bowel (n=4) or bladder and collecting system (n=7) in a subset of patients with postnatal complications (anorectal 4/4, PPV 100%; urologic 6/7, PPV 86%). Postnatal complications were associated with obstructive findings on prenatal imaging, prenatal therapeutic interventions, Altman classification, perineal reconstruction, and tumor recurrence. No anorectal or urologic complications occurred in patients with Altman type I tumors. CONCLUSIONS: Urologic and anorectal complications are common in patients with SCT. Higher Altman classification and prenatal imaging suggestive of intestinal or urologic obstruction should prompt focused prenatal counseling and postnatal screening for anorectal and urologic dysfunction.

Outcome and etiologies of fetal megacystis according to the gestational age at diagnosis.

OBJECTIVE: To investigate the gestational age-specific outcomes and the different etiologies of megacystis diagnosed at screening ultrasound. METHODS: A retrospective single-center study was conducted between 1989 and 2009. We identified all consecutive cases of megacystis prenatally diagnosed during routine ultrasound screening. Outcome, final diagnosis, and renal function were recorded. RESULTS: Eighty-four patients were included. An isolated lower urinary tract obstruction was observed in 38/84 (45.2%), ureterovesical reflux in 9/84 (10.7%), an associated congenital abnormality in 32/84 (38.1%) and a normal bladder in 5/84 (6%). Increased gestational age at diagnosis was correlated with an increased rate of live born children (P < 0.01). No cases of megacystis diagnosed in the first trimester were born alive. When diagnosis of posterior urethral valves (PUV) was made in the third trimester, the ultimate survival rate was 11/13 (84.6%) compared with 3/12 (25%) for a diagnosis made in the second trimester (P = 0.02). CONCLUSION: Lower urinary tract obstruction is the main etiology of megacystis. Megacystis can also be part of more complex malformations. Outcome of megacystis detected in the first trimester is poor. PUV detected in the third trimester had a better overall survival rate than PUV detected in the second trimester.

Preterm prelabor rupture of membranes and fetal survival after minimally invasive fetal surgery: a systematic review of the literature.

OBJECTIVE: Iatrogenic preterm prelabor rupture of membranes (iPPROM; <37 weeks of gestation) is a major complication of fetal surgery. Little information is available about risk factors and incidence. METHODS: We systematically reviewed reported iPPROM rates, gestational age at delivery and fetal survival after representative minimally invasive antenatal procedures. RESULTS: A total of 1,146, 36 and 194 cases with mean iPPROM rates of 27, 31 and 26% were included for placental laser in twin-twin transfusion syndrome, shunting in lower urinary tract obstruction and interventions for twin-reversed arterial perfusion, respectively. In the statistical analysis, the maximum diameter of the instrument predicted iPPROM rate and was significantly related to gestational age at birth as well as fetal survival. Information on duration of the respective procedures was scarce and did not allow for meaningful analysis. CONCLUSIONS: iPPROM occurs in about 30% of cases treated by minimally invasive fetal surgery. The maximum diameter of the instrument explains iPPROM rate, gestational age at birth and fetal survival. Great variations in the reporting of iPPROM make data analysis difficult.

Effect of increased intra-abdominal pressure on urinary system development in fetal rabbits.

AIM: To investigate the effect of increased intra-abdominal pressure (IAP) on the fetal urinary system. MATERIALS AND METHODS: Pregnant rabbits (15-day gestation) were used. Control (n = 5) and experimental (EG, n = 4) groups underwent intraperitoneal catheter placement. The IAP was increased by intraperitoneal air insufflations during the third trimester in the EG. At term, organ weight and organ weight/body weight (BW) ratios were noted, histological examination of the urinary system organs was performed, and the apoptotic indexes were calculated. RESULTS: BW and total renal weight were significantly increased in the EG (38.65 ± 8.34 g vs 49.36 ± 8.81 g, p = 0.008; and 0.406 ± 0.132 g vs 0.531 ± 0.129 g, p = 0.02). Total renal weight/BW ratio did not differ between groups (0.0103 ± 0.001 vs 0.0107 ± 0.001; p = 0.33). Bladder weight and bladder weight/BW ratio was also significantly increased in the EG (0.067 ± 0.014 g vs 0.114 ± 0.026 g, p = 0.00; and 0.00175 ± 0.00026 vs 0.00229 ± 0.00036, p = 0.001). Immature glomeruli and collecting tubules, and a thin and underdeveloped muscular layer in the ureter and bladder were encountered in the EG, and the apoptotic cell index was significantly increased (p < 0.05). CONCLUSION: Increased IAP has an adverse effect on fetal urinary system development, and may play a role in the pathogenesis of various congenital abnormalities of the urinary system.

Fetal urinoma in females without obstructive uropathy.

OBJECTIVE: Prenatal diagnosis of urinomas has long been established with underlying obstructive uropathy generally responsible for urinary extravasation. Because urinoma formation represents a pop-off mechanism in cases of posterior urethral valves, the number of affected males greatly exceeds the number of females. Fetal urinoma has rarely been reported without obstruction and in females it has only been described as a consequence of a complicated amniocentesis. METHODS: Three cases of fetal urinoma in female fetuses without any dilatation of the urinary tract are described. Since the fetus remained healthy, they were all conservatively managed. RESULTS: Two urinomas resolved after birth and 1 exhibited significant regression. In the second case, a compressed kidney was visualized with fetal MRI. Renal function was impaired in cases 1 and 3 and absent in case 2 (the kidney was no longer visualized). CONCLUSIONS: Fetal urinomas can occur even in the absence of urinary tract obstruction and in a low-pressure system as is found in female fetuses. Fetal MRI may help both visualize the ipsilateral kidney and differentiate the mass from other conditions. In a healthy fetus, fetal urinomas can be conservatively managed, but renal function after birth is often absent or impaired. Whether or not in utero aspiration may be beneficial for the preservation of renal function remains unclear.

Prenatal diagnosis: what do we know of long-term outcomes?

Although prenatal diagnosis has been a prominent feature of Paediatric Urology for more than two decades the published literature has been largely characterized by studies reporting short to medium-term follow up. This deficiency is now being addressed by the growing availability of published and unpublished long-term outcome data for a range of prenatally detected anomalies. This review analyses the evidence on long-term outcomes which is provided by studies with mean or median follow- up exceeding 5 years, with particular emphasis on the small number of studies reporting follow -up at 10 years and beyond. The natural history and outcome of conservatively managed uropathies is considered in conjunction with an appraisal of evidence- based indications for surgical intervention. This review evaluates the relative benefits and drawbacks of prenatal diagnosis for children and their parents and also considers the impact of prenatal diagnosis on the delivery of Paediatric Urological services and specialist training.

Magnetic resonance imaging in fetal medicine: a pictorial review of current and developing indications.

Improvements in magnetic resonance (MR) imaging now permit diagnostic images of the fetus to be obtained. Ultrasound remains vital in all aspects of fetal imaging but MR provides a useful second line imaging test. Its value is best researched in fetal central nervous system disorders but it can be applied in other areas too. This pictorial review shows many of the commonly encountered problems. The pictures have a powerful impact on parental understanding. Future research must involve determination of the prognosis of abnormalities found at MR.

Diagnostic accuracy of postnatal ultrasound screening for urinary tract abnormalities.

The study was aimed at (1) the determination of the incidence of abnormalities of the urinary tract in newborn infants detected by postnatal ultrasound screening, and (2) the evaluation of the diagnostic accuracy of postnatal ultrasound screening for detecting surgical urinary tract abnormalities. The prospective study was of full-term neonates born in the University Hospital of Olomouc in 2005-2008 who underwent renal ultrasound screening after 72 h of life. Significant findings were recorded. Subsequent diagnostic and therapeutic procedures were recorded and evaluated in a group of children with detected renal pelvic dilatation (RPD). (1) A total of 6,088 newborn infants was examined. The absolute and relative RPD incidence rates (anteroposterior diameter, APD) were as follows: 5-7 mm, 146 (2.4%); 7-10 mm, 70 (1.15%); 10-15 mm, 13 (0.21%), and 15 mm or more, 5 (0.08%). Of those, 16 children were operated on for abnormalities of the urinary tract, of which nine (56%) had been detected by prenatal screening. Other findings: six cases of unilateral renal agenesis, four cases of multicystic renal dysplasia, four of renal dystopia, one of polycystic kidney disease and one of renal hypoplasia. (2) A group of 224 children with postnatally detected RPD was examined, of whom 40 (17.9%) underwent voiding cystourethrography and/or scintigraphy and 16 (7.1%) were treated surgically. The receiver operating characteristic curves were analyzed, and the areas under the curves were calculated. Postnatal renal ultrasound screening is probably a suitable test for detecting significant urinary tract abnormalities.

Genetic and developmental basis for urinary tract obstruction.

Urinary tract obstruction results in obstructive nephropathy and uropathy. It is the most frequent cause of renal failure in infants and children. In the past two decades studies of transgenic models and humans have greatly enhanced our understanding of the genetic factors and developmental processes important in urinary tract obstruction. The emerging picture is that development of the urinary tract requires precise integration of a variety of progenitor cell populations of different embryonic origins. Such integration is controlled by an intricate signaling network that undergoes dynamic changes as the embryo develops. Most congenital forms of urinary tract obstruction result from the disruption of diverse factors and genetic pathways involved in these processes, especially in the morphogenesis of the urinary conduit or the functional aspects of the pyeloureteral peristaltic machinery.