Abnormal Kidney Location
Abstract There are three abnormalities of kidney location: simple renal ectopia or pelvic kidney, crossed renal ectopia, and horseshoe kidney. Simple renal ectopia is a kidney that is located on…
Hydrothorax
Abstract Fetal hydrothorax is an intrathoracic effusion that arises in the fetus, may occur unilaterally or bilaterally, and may be primary or secondary. It constitutes a nonspecific finding, because it…
Scimitar Syndrome
Abstract Scimitar syndrome is a rare congenital pulmonary anomaly characterized by a unilateral anomalous pulmonary venous drainage consisting of an aberrant vein that drains the lung blood flow into the…
Other Thoracic Tumors and Masses
Abstract Other thoracic tumors can be found in fetal life, which are not described in previous chapters. Bronchogenic cysts are masses derived from abnormal budding of the ventricular diverticulum that…
Posterior Urethral Valves
Abstract The most common cause of fetal bladder outlet obstruction is posterior urethral valves. Ultrasound examination shows a dilated, thick-walled bladder, often with dilatation of the proximal urethra—the “keyhole” sign….
Abnormal Kidney Size
Abstract Measurement of fetal kidney size can assist in the diagnosis when a renal abnormality is suspected. Fetal kidney size increases with gestational age. Nomograms are available for kidney length,…
Bilateral Renal Agenesis
Abstract Bilateral renal agenesis is the congenital absence of both kidneys and ureters. Also known as Potter syndrome, it is a lethal anomaly in which absence of the kidneys results…
Renal Pelvis Dilatation
Abstract Fetal renal pelvis dilatation is identified in 1% to 5% of pregnancies and is often a transient, normal variant. The likelihood of an underlying abnormality increases with the degree…
Unilateral Renal Agenesis
Abstract Unilateral renal agenesis has a birth prevalence of approximately 1 : 1000 to 1 : 2000, but it is often undetected prenatally. Sonographically, one kidney cannot be visualized in either the renal fossa…
Duplicated Collecting System
Abstract Duplication of the renal collecting system is recognized in approximately 1 : 4000 pregnancies and is more frequent in females. It disproportionately affects the left kidney, and is bilateral in 15%…
