Content uploaded by Frederica Papadopoulou
Author content
All content in this area was uploaded by Frederica Papadopoulou on Mar 12, 2014
Content may be subject to copyright.
ESPR
ESPR uroradiology task force and ESUR Paediatric
Work Group—Imaging recommendations in paediatric
uroradiology, part VI: childhood renal biopsy and imaging
of neonatal and infant genital tract
Minutes from the task force session at the annual ESPR Meeting 2012 in Athens
on childhood renal biopsy and imaging neonatal genitalia
Michael Riccabona &Maria Luisa Lobo &Ulrich Willi &Fred Avni &
Beatrice Damasio &Lil-Sofie Ording-Mueller &Johan Blickman &
Kassa Darge &Frederika Papadopoulou &Pierre-Hugues Vivier
Received: 28 March 2013 /Revised: 22 May 2013 /Accepted: 1 July 2013
#Springer-Verlag Berlin Heidelberg 2014
Abstract The European Society of Paediatric Radiology
Uroradiology Task Force and the ESUR Paediatric Work
Group jointly publish guidelines for paediatric urogenital
imaging. Two yet unaddressed topics involving patient
safety and imaging load are addressed in this paper: renal
biopsy in childhood and imaging of the neonatal genital
tract, particularly in girls. Based on our thorough review
of literature and variable practice in multiple centers,
procedural recommendations are proposed on how to
perform renal biopsy in children and how to approach
the genital tract in (female) neonates. These are state-
ments by consensus due to lack of sufficient evidence-
based data. The procedural recommendation on renal
biopsy in childhood aims at improving patient safety
and reducing the number of unsuccessful passes and/or
biopsy-related complications. The recommendation for an
imaging algorithm in the assessment of the neonatal
genital tract focuses on the potential of ultrasonography
to reduce the need for more invasive or radiating imag-
ing, however, with additional fluoroscopy or MRI to be
used in selected cases. Adherence to these recommenda-
tions will allow comparable data and evidence to be
generated for future adaptation of imaging strategies in
paediatric uroradiology.
M. Riccabona (*)
Department of Radiology, Division of Paediatric Radiology,
Medical University and University Hospital LKH Graz,
Auenbruggerplatz 34, A - 8036 Graz, Austria
e-mail: michael.riccabona@klinikum-graz.at
M. L. Lobo
Department of Radiology, Hospital de Santa Maria-CHLN,
University Hospital, Lisbon, Portugal
U. Willi
Department of Radiology, Johns Hopkins University,
Baltimore, MD, USA
F. Avn i
Department of Pediatric Radiology, Jeanne de Flandre Hospital,
CHRU de Lille, Lille Cedex, France
B. Damasio
Department of Radiology, Gaslini Institute, Genoa, Italy
L.<S. Ording-Mueller
Department of Radiology and Nuclear Medicine, Unit for Paediatric
Radiology, Oslo University Hospital, Oslo, Norway
J. Blickman
Department of Radiology, University of Rochester, School of
Medicine, Rochester, NY, USA
K. Darge
Department of Radiology, Children’s Hospital of Philadelphia,
Philadelphia, PA, USA
F. Papadopoulou
Department of Radiology, Ioannina University Hospital,
Ioannina, Greece
P.<H. Vivier
Hôpital Privé de l’Estuaire, Radiologie,
505 rue Irène Joliot Curie, 76620 Le Havre, France
Pediatr Radiol
DOI 10.1007/s00247-013-2852-5
Keywords Recommendations .Children .Kidney biopsy .
Genital tract malformations
Introduction
There is a wide variety of pediatric urogenital imaging in differ-
ent centres. In order to homogenize, ease and improve the
specific imaging approach, the ESPR Uroradiology Task Force
and the ESUR Paediatric Work Group set out to assess available
standards, explore different existing practices, review available
literature and jointly draft a proposal for a unified imaging
approach. The goal is to standardize imaging at its lowest possi-
ble invasiveness by adhering to the ALARA principle to reduce
the risk of potential complications and to provide reliable results.
The recommendations intend to be comprehensive and to be as
basic and practical as possible to encourage their use around the
world. This includes the flexibility for adjusting to individual
needs and situations (“personalized medicine”). With the given
restriction of available evidence from literature, these recommen-
dations are issued as a consensus statement based on thorough
review of literature, assessment of the different practices in
various centres, and consultation of other related subspecialties
dealing with pediatric urogenital conditions.
The group hopes for a wide distribution of and adherence
to these new recommendations, which are designed to create
comparable data for future meta-analysis and improve evi-
dence level and, thus, uroradiological practice in children.
Renal biopsy in childhood
Renal biopsies in children are performed by various specialists
for different indications and under variable imaging guidance,
most commonly using ultrasonography (US). However, in
some centers, renal biopsies are performed without any imag-
ing guidance (i.e. blindly). The indication for biopsy is usually
defined by the referring paediatric nephrourologist or trans-
plantation specialist. The inherent risks are haemorrhage, in-
jury to the collecting system or arterial-venous fistula (AVF)
as potential threats to the kidney. The risk for these complica-
tions increases with the number of passes and needle size.
While sufficient material must be provided by the procedure
to allow for meaningful histology, the amount of renal tissue
depends on the suspected condition.
The procedure requires a team-approach by the involved
nephrourologist, paediatric anaesthesiologist (analgesia, seda-
tion and monitoring), histopathologist, nurse and/or technician,
as well as paediatric and/or interventional radiologist. A standard
intervention suite with all necessary equipment and instrumen-
tation available (including monitoring device, oxygen, material
for sterile handling, spotlight and microscope) and an open
layout is most desirable. Preceding the biopsy, the child’s
general condition must be assessed as part of a work-up of the
nephrourological complaint. In addition, a detailed pre-
interventional US with colour Doppler sonography (CSD) is
indispensable to assess for renal localization and potential risk
factors (e.g. duplex kidney with small lower pole system, aber-
rant vessels, interfering structures, etc.). Preprocedural decision
on instrumentation availability and detail is crucial: i.e. size and
length of the needle, length of the core cut (which depends on
parenchymal thickness), whether coaxial technique is advisable
in more difficult access, etc. Patient preparation includes intra-
venous line, emptied bladder and pre-sedation, as well as a skin-
numbing patch or paste administered at the presumed biopsy
site. Time-out must be granted to confirm the patient’s identity,
the indication of the procedure and adequate recent haemato-
logical status with regard to bleeding and coagulation, as well as
whether informed consent has been obtained.
The child is placed in prone position with adequate ventral
support for biopsy of the native kidney. Pre-interventional US is
performed for probe positioning and as baseline for post-
interventional follow-up. The lower pole of the native left kidney
is commonly targeted and the access area is defined by US. In a
transplant kidney, the patient is typically supine and a safe needle
approach (e.g. from the laterocranial aspect) is selected by US.
Local anaesthesia is strongly recommended even with the child
in deep sedation. Correct sterile conditions are mandatory for the
procedure. Biopsy in younger patients is commonly performed
under deep analgo-sedation, administered by the anaesthesiolo-
gist. Conscious analgo-sedation may be chosen in older chil-
dren. Monitoring of blood pressure, heart/respiratory rate and
oxygenation is required throughout the procedure. Biopsy
should be performed under direct real-time vision and is best
with the help of the dedicated needle guide attached to the
transducer. The length of the core cut is defined by the thickness
of the renal parenchyma (avoid a long cut into narrow paren-
chyma and injury to the collecting system). Use of an 18-gauge
needle is usually adequate for core thickness as well as to
minimize the risk of vascular complication. CDS is extremely
helpful in avoiding renal vascularity, especially major vessels.
Sufficient cortical material, i.e. a sufficient number of glomeruli,
is necessary for establishing a diagnosis; medullary tissue is
rarely required. Details of specific tissue need to be discussed
with the referring nephrologist in advance to select the biopsy
area. Commonly, a biopsy gun or a semi-automated biopsy
device is used and fired under direct US vision. CDS demon-
strates even more conspicuously the risk for potential post-
biopsy complications (Table 1). Whether a second pass is nec-
essary for diagnosis needs to be determined by the on-site
paediatric nephrologist or histopathologist by evaluating the
specimen immediately (preferably under the microscope) for
diagnostic adequacy. Upon retrieving the needle, local compres-
sion is applied to prevent haemorrhage. For repeat biopsy passes,
the biopsy area/needle placement should be changed to mini-
mize the risk of complications or an unsuccessful second pass.
Pediatr Radiol
Immediate postprocedural US with CDS is performed
for potential haemorrhage, parenchymal alteration or AVF.
Focal rarefaction of peripheral renal vasculature at the
biopsy site immediately after the procedure is a frequent
reactive phenomenon and is considered physiological. In
severe renal disease as well as in antihypertensive treat-
ment, vascular reaction may be decreased. Therefore, with-
drawal of reno-active drugs two days before suggested if
clinically feasible.
Post-biopsy handling includes local pressure, bed rest for at
least 3 to 6 h, monitoring of vital parameters (blood pressure,
heart rate, haematocrit) and urinalysis. Thorough follow-up US
and CDS includes the biopsy area (for potential occurrence of
haematoma, active bleeding, clot formation in the collecting
system, perirenal collections and arterio-venous fistulation), and
the entire urinary tract with the bladder (for clots as well as for
urine inflow from the tapped kidney). All abdominal compart-
ments should then be evaluated for fluid collections. Depending
Ta b l e 1 How to perform renal
biopsy in infants and children Prerequisites Indication given by paediatric nephrourologist.
Informed consent.
Necessary blood test-results (e.g. coagulation status).
Monitoring and resuscitation facilities.
Empty bladder.
Anaesthetic cream applied to any possible access site.
Intravenous access.
Consider conscious sedation and local anaesthetic for children ages 12 years and above,
otherwise local anaesthetic and deep sedation/general anaesthetic depending on local
guidelines.
Instrumentation (Semi-)automatic biopsy gun with matching needle as chosen by preoperative US.
Needle length depends on kidney depth and thickness.
Needle calibre, 18 G–20 G.
Sample length, 1.2 cm–2.2 cm depending on parenchymal thickness and biopsy gun.
Coaxial technique should be used for deep sampling and difficult access.
Materials Disinfectant, local anaesthetic for injection, knife for skin incision, sterile covers (for child
and for equipment), sample handling materials, US machine with transducer optimized for
the size of the child.
Procedure Initial US (child awake). Is the urinary bladder empty?
Sedation and positioning Sedation as above.
Position prone (native kidney biopsy) or supine
(transplant kidney biopsy).
Site preparation Preliminary US with external marking (target lower pole of left
kidney if possible) considering the respiratory dynamics of
the
kidney.
Skin incision after definition of biopsy site under direct US
view, ideally using colour Doppler for optimal vascular
sparing.
Biopsy pass Aim at mediodorsal “avascular”line defining the needle tract
parallel to main vascular plane.
The guide needle should be advanced to just superficial to the
renal capsule.
Advance biopsy needle to just deep to the renal capsule.
Perform biopsy shot with real-time US documentation.
Repeat if necessary keeping the number of passes to a
minimum.
Evaluation of specimen Inspect specimen.
Immediate post-biopsy
US
Document biopsy site, any haemorrhage or visible
arteriovenous fistula.
Post-biopsy Effective compression of biopsy site also using positioning.
Standardized monitoring for interventional procedures with potential vascular complications.
Rescanning with US 4 h–6hand12h–24 h after biopsy, always including colour Doppler.
Prolonged monitoring and bed rest in case of complications (significant bleeding, AVF etc.).
Pediatr Radiol
on the findings and the further management of the patient, a
subsequent or final US evaluation may be suggested at 12 and 24
to 48 h after the procedure, potentially on an outpatient basis.
Absence of any major haematoma, haemorrhage, AVF or blad-
der clot is expected. Withdrawn reno-active antihypertensive
drugs may be reinstalled, even if minor haemorrhagic residuals
are present. In these conditions, conservative management with
repeat monitoring is advised, as most of these findings resolve
spontaneously. Severe haemorrhage, large AVF with high shunt
flow that endanger renal perfusion and function, or large clots in
the collecting system and/or bladder might indicate active treat-
ment, possibly even embolisation of AVF (Table 1).
Imaging the genital tract in the neonate and infant
To carry out a practical and differentiated imaging approach after
birth, a few prerequisites need to be kept in mind. These are:
1. Knowledge of the basic organogenetic facts and fetal
development of the urogenital tract.
2. Familiarity with the normal appearance of inner genitalia
in neonates and infants, especially in a female (character-
istic shape and large size of uterus; frequent presence of
even large ovarian follicles).
3. Knowledge of the characteristic morphology in common
genital malformations.
4. Awareness of the frequent association with urinary tract
malformations (e.g. multicystic dysplastic kidney, unilat-
eral renal dysplasia, single kidney).
Therefore, early diagnostic imaging of the genital or uri-
nary tract should always include both systems. Early imaging
in a female also offers the advantage of the usually prominent
neonatal genital morphology.
Common indications for the evaluation of the urogenital
tract by imaging include known or suspected fetal abnormality,
a clinically apparent genital malformation, ambiguous genitalia,
cloacal malformation, urogenital sinus, Müllerian duct and
vaginal abnormality and congenital adrenal hyperplasia, as well
as undescendend testis, congenital inguinal hernia and the
various types of congenital hydrocele, cystic dysplasia of the
rete testis and cystic-dysplastic seminal vesicles. Disorders of
sexual differentiation (intersex) include a wide and complex
group of abnormalities resulting from non-accordance between
chromosomal, gonadal and genital gender. Due to their com-
plexity and the need for a multidisciplinary team approach, these
latter patients should be referred to a dedicated pediatric centre.
Ultrasoundincluding CDS is the primary imaging modality
to evaluate both male and female genitalia and urinary tract.
Dedicated and expert US technique is essential to obtain
adequate diagnostic information (Table 2). In females, a sys-
tematic transabdominal and transperineal US approach of the
pelvic cavity with a full or filled bladder is fundamental.
Whenever genital US is insufficient for adequate characteri-
zation of some uterovaginal abnormality or if vaginal dupli-
cation is suspected, a specific sonographic genitography is
recommended. It consists of some innocuous fluid
(prewarmed saline) instillation into the vagina through a small
flexible feeding tube that improves or even allows visualiza-
tion, particularly of the vagina and cervix (Table 3). Addition-
al rectal saline filling may be useful, e.g. for fistula detection
or in Müllerian duct agenesis, assuring the absence of uterus.
Ta b l e 2 Neonatal female genital US
Preparation Good hydration.
Full bladder if possible (else consider filling
the bladder with saline using a 4-F to 5-F
catheter.)
Target anatomy Entire genital tract, Entire urinary tract.
Adrenals.
Potentially the distal spinal cord.
Transducer High-resolution linear.
Additionally consider 3-D transducer.
Assessments using
transabdominal
approach
Uterus, cervix, vagina, ovaries: size,
morphology, position, obstruction.
Standard complete assessment of the urinary
tract.
Assessments using
transperineal approach
Vagina, cervix, urethra, anal canal: position,
patency, filling and emptying.
Level of any obstruction (distance from
obstruction to perineal orifice).
Technique for 3-D US
genitography
3-D acquisition with coronal (thick-slab)
reconstructions may improve the
definition and characterisation of uterine
and/or vaginal abnormalities.
Ta b l e 3 US-genitography–procedural recommendation
Indications Complementary to standard US for depiction of
malformations.
Preparation Vaginal catheterization under sterile conditions.
8-F feeding tube, thinner if urogenital sinus tract; avoid
any air in catheter.
Infusion
technique
Infuse saline continuously (to compensate for vaginal
leakage).
Optimally add US contrast agent to saline.
Additional rectal instillation of saline may be helpful.
If bladder fails to fill via urogenital sinus, blind bladder
catheterization with second (curved-tip) catheter.
Scan
technique
Combine transabdominal and transperineal approaches.
Include kidneys.
Consider adding 3-D acquisition.
Proceed with voiding cysto-urethro sonography for
evaluation of vesicoureteral reflux, if needed.
Pediatr Radiol
Subsequent complementary imaging procedures may in-
clude fluoroscopic genitography and (ce-)MRI (Table 4,
Fig. 1). (T2-) MR-urography may be added for evaluation of
associated orcombined urinary tract malformations. There are
very few indications for a technically dedicated ce-CT (e.g. if
no MRI available in complex anatomy for preoperative as-
sessment, such as in cloacal malformations or coexisting
orthopedic abnormality involving the pelvis and/or lower
spine). Sectional imaging should not be performed as a base-
line study but be strictly reserved for selected cases and
usually for surgical planning. Notice that, unlike in adults or
in older children, MRI evaluation of the genital tract is limited
in neonates and infants due to resolution issues and may
therefore be less useful. A high-resolution 3-D sequence after
saline instillation into the vagina and bladder as well as rectal
filling with diluted contrast material may yield more differen-
tiated anatomical information. It is important to remember that
imaging evaluation of genital (and also cloacal)
malformations is never an emergency procedure. This holds
true for almost all complex urogenital malformations in new-
borns with a normal amount of amniotic fluid, i.e. with normal
Ta b l e 4 Fluoroscopic genitography–procedural recommendation
Indications Complementary to US for depiction of complex
malformations.
For surgical planning.
Timing In same session as US to reuse catheters and
reduce invasiveness, or preoperatively.
Preparation Vaginal catheterization under sterile conditions.
8-F feeding tube, thinner if urogenital sinus tract,
avoid any air in catheter.
Skin markers on perineal external orifices.
Assessment of the
bony pelvis
Look for spinal/sacral abnormalities.
Fluoroscopic
technique
Water-soluble iodinized contrast medium
(100 mg I/ml, or less).
AP and lateral / oblique spot views.
If bladder fails to opacify via urogenital sinus,
blind bladder catheterization with second
(curved-tip) catheter.
Proceed with voiding cystourethrography for
evaluation of vesicoureteral reflux, if needed.
Fig. 1 Imaging algorithm –how to assess the neonatal female genital tract / pelvis legend: proposal on how to approach neonates with suspected genital
anomalies. Abbreviations: UT = urinary tract, MRI = Magnetic resonance Imaging, pre-op = pre-operatively, US = ultrasound
Pediatr Radiol
renal function and adequate vital signs. Complex diagnostic
imaging should be well prepared and is best performed as an
elective study under interdisciplinary cooperation in dedicated
centres.
Summary
Renal biopsy should be performed in children with special
precautions and under dedicated conditions to avoid poten-
tially severe complications. The procedure must be standard-
ized. This includes careful pre-interventional preparation with
detailed US (including CDS), performance under direct US-
guidance, use of an optimal core cut needle and a biopsy gun
or (semi-)automated biopsy device, prompt tissue evaluation
and a thorough post-interventional follow-up (Table 1).
Congenital malformations of the neonatal genital tract are
common. Ultrasonography is the first and basic imaging mo-
dality and is often diagnostically sufficient (Table 2). Proper US
technique complemented by US-genitography may be crucial
for a reliable diagnosis (Table 3). Competent US is fundamental
in deciding which patients will need complementary imaging
with fluoroscopic genitography and/or MRI (Table 4and
Fig. 1), typically reserved for complex malformations and
particularly for planning surgical intervention.
Conflict of interest There is no financial or other interest concerning
the reported topic.
References
Renal biopsy
1. Davis ID, Oehlenschlager W, O’Riordan MA et al (1998) Pediatric
renal biopsy: should this procedure be performed in an outpatient
setting? Pediatr Nephrol 12:98–100
2. Dodge WF, Daescher CW, Brennan JC et al (1962) Percutaneous renal
biopsy in children—general considerations. Pediatrics 30:287–296
3. Feld LG, StapletonFB, Duffy L (1993) Renal biopsy in childrenwith
asymptomatic hematuria or proteinuria: survey of pediatric nephrol-
ogists. Pediatr Nephrol 7:441–443
4. Hussain F, Mallik M, Marks SD et al (2010) Renal biopsies in
children: current practice and audit of outcomes. Nephrol Dial
Transplant 25:485–489
5. KanzelmeyerNK, Ahlenstiel T, Drube J et al (2010) Protocol biopsy-
driven interventions after pediatric renal transplantation. Pediatr
Transplant 14:1012–1028
6. Memis A, Killi R, Ozer H (1992) Renal arteriovenous fistula after
kidney biopsy: colour Doppler ultrasound and angiography diagnosis
with embolization using the same procedures. Bildgebung 59:200–
202
7. Merkus W, Zebregts CJ, Hoitsma AJ et al (1993) High incidence of
arteriovenous fistula after biopsy of kidney allografts. Brit J Surg 80:
310–312
8. Obek SS, Memis A, Killi R et al (1995) Image directed and color
Doppler ultrasonography in the diagnosis of postbiopsy arteriove-
nous fistula of native kidneys. J Clin Ultrasound 23:239–242
9. Printza N, Bosdou J, Pantzaki A et al (2011) Percutaneous
ultrasound-guided renal biopsy in children: a single centre experi-
ence. Hippokratia 15:258–261
10. Riccabona M, Ring E (1995) Ultrasound guided renal biopsy in
childhood—value of Colour Doppler Sonography [Sonographisch
gezielte Nierenbiopsie im Kindesalter—Rolle der
Farbdopplersonographie]. Wien Klin Wochenschr 107:252–255
11. Riccabona M, Schwinger W, Ring E (1998) Arteriovenous fistula
after renal biopsy in children. J Ultrasound Med 17:505–508
12. Riccabona M, Mache CJ, Ring E (2008) Renal biopsy. In: Fotter R
(ed) Pediatric uroradiology, 2nd edn. Springer, Berlin-Heidelberg-
New York, pp 375–377
13. Riccabona M, Sorantin E, Hausegger K (2002) Imaging guided
interventional procedures in paediatric uroradiology—acasebased
overview. Eur J Radiol 43:167–179
14. Riccabona M (2004) Interventional uroradiology in paediatrics: A
potpourri of diagnostic and therapeutic options. Minerva Pediatr 56:
497–505
Childhood genital imaging
15. Ahmed SF, AchermannJC AW et al (2011) UK guidance on the initial
evaluation of an infant or an adolescent with a suspected disorder of
sex development. Clin Endocrinol 75:12–26
16. Chavhan GB, Parra DA, Oudjhane K et al (2008) Imaging of ambig-
uous genitalia: classification and diagnostic approach. Radiographics
28:1891–1904
17. Garel L, Dubois J, Grignon A et al (2001) US of the pediatric female
pelvis: a clinical perspective. Radiographics 21:1393–407
18. Gassner I, Geley TE (2004) Ultrasound of female genital anomalies.
Eur Radiol 14:L107–L122
19. Geley TE, Gassner I (2008) Lower urinary tract anomalies of uro-
genital sinus and female genital anomalies. In: Fotter R (ed) Pediatric
uroradiology, 2nd edn. Springer, Berlin-Heidelberg, pp 137–163
20. Adams ME, Hiorns M, Wilcox DT (2006) Combining MDCT, mic-
turating cystography, and excretory urography for 3D imaging of
cloacal malformation. AJR Am J Radiol 187:1034–1035
21. Hughes IA, Houk C, Ahmed SF et al (2006) Consensus statement on
management on intersex disorders. Arch Dis Child 91:554–563
22. Huisman TAG, van der Hoef M, Willi UV et al (2006) Pre- and
postnatal imaging of a girl with a cloacal variant. Pediatr Radiol 36:
991–996
23. Junqueira BLP, Allen LM, Spitzer RF et al (2009) Müllerian duct
anomalies and mimics in children and adolescents: correlative intra-
operative assessment with clinical imaging. Radiographics 29:1085–
1103
24. Kiechl-Kohlendorfer U, Geley T, Maurer K et al (2011) Uterus
didelphys with unilateral vaginal atresia: multicystic dysplastic kid-
ney is the precursor of “renal agenesis”and the key to early diagnosis
of this genital anomaly. Pediatr Radiol 41:1112–1116
25. Kiechl-Kohlendorfer U, Geley TE, Unsinn KM et al (2001)
Diagnosing neonatal female genital anomalies using saline-
enhanced sonography. AJR Am J Roentgenol 177:1041–1044
26. KopačM, Riccabona M, Haim M (2009) Contrast-enhanced voiding
Uurosonography and—genitography in a baby with ambiguous gen-
italia and urogenital sinus [Kontrastverstärkte sonografische
Miktionszysto-urethrografie und -genitografie bei einem Kind mit
intersexuellem Genitale und Sinus urogenitale]. Ultraschall in Med
30:299–300
27. Lang IM, Babyn P, Oliver GD (1999) MR imaging of paediatric
uterovaginal anomalies. Pediatr Radiol 29:163–170
Pediatr Radiol
28. Öçal G (2011) Current concepts in disorders of sexual development. J
Clin Res Pediatr Endocrinol 3:105–114
29. Orazi C, Lucchetti MC, Schingo PMS et al (2007) Herlyn-Werner-
Wunderlich syndrome: uterus didelphys, blind hemivagina and ipsi-
lateral renal agenesis. Sonographic and MR findings in 11 cases.
Pediatr Radiol 37:657–665
30. Riccabona M (2006) Imaging of the neonatal genito-urinary tract.
Eur J Radiol 60:187–198
31. Riccabona M (2011) Potential role of 3DUS in infants and children.
Pediatr Radiol 41:S228–237
32. Ehammer T, Riccabona M, Maier E (2011) High resolution MR for
evaluation of lower urogenital tract malformations in infants and
children: feasibility and preliminary experiences. Eur J Radiol 78:
388–393
33. Wang ZJ, Daldrup-Link H, Coakley FV et al (2010) Ectopic
ureter associated with uterine didelphys and obstructed
hemivagina: preoperative diagnosis by MRI. Pediatr Radiol 40:
358–360
34. Ziereisen F, Guissard G, Damry N et al (2005) Sonographic imaging
of the paediatric female pelvis. Eur Radiol 15:1296–1309
Pediatr Radiol
