Dr/Ahmed Bahnassy

Consultant radiologist

RMH

• Echostructure.

• Size.

• Variations.

• Congenital anomalies.

• Renal abnormality.

RENAL ANATOMY

RENAL CORTEX

MEDULLA

MAJORCALYCES

RENALPELVIS

RENALMEDULLARYPYRAMID

RENALCAPSULEURETER

MINORCALYX

RENAL COLUMN

NORMAL RENAL SONOGRAPHY

• Paired retroperitoneal organs

• Renal sinus- dense central echoes due to renal fat– Contains:

• Collecting system: calyces, infundibula, & part of renal pelvis

– bifid system seen as two separate lobulations

• Renal vessels: renal hilium• Lymphatics• Fat• Fibrous tissues

RENAL SINUS

• Central area of the kidney from the medial border

• Bounded by fat– anteriorly and posteriorly by

fibrous sheath known as Gerota’s fascia

– laterally by the laterocoronal fascia which becomes continuous with peritoneum & abdominal wall

RENAL SONOGRAPHY• Renal parenchyma - 2 parts cortex & medulla

– thickest at the renal poles

• Cortex located between capsule & medulla

– low level uniform echoes

– less echogenic than liver & spleen

– Columns of Bertin = columns of cortical tissue located between pyramids

» can enlarge & mimic a mass

» normal variant

• medulla

– renal volume is estimated by water displacement

• V = 0.49 x length x width x anterior posterior dimension

RENAL SONOGRAPHY

• Renal parenchyma - 2 parts cortex & medulla

– Medulla

• Pyramids - triangular or rounded hypoechoic areas

• Rounded zones of decreased echogenicity between cortex & renal sinus

• Specular echoes interspersed at the junction of the cortex & medulla represents arcuate arteries & veins (known as corticomedullary junction)

Dysplastic kidney

RENAL SONOGRAPHY

• Vascular exchange– renal arteries

• come off of aorta - can be multiple• right renal artery (RRA) - seen posterior to IVC in

sagittal plane

– renal veins• come off of IVC• left renal vein (LRV) - seen between SMA & aorta

in the transverse plane

RENAL ARTERY

RENAL SIZE

Normal renal sizeNormal Liver, Spleen, and KidneyDimensions in Neonates, Infants,and Children: EvaluationwithSonography.. AJR:171,December1998

Development

Anomalies and variations• Congenital variations

– fetal lobulations– dromedary hump.– Fusion anomalies :horseshoe -

isthmus of tissue that connects both kidneys

– Ascent anomalies: pelvic kidney fails to migrate from pelvic area during embryology

• Normal neonatal kidney should be evaluated according to:

• Normal echotexture.• Normal size for age.• Normal development.• Excluding normal variants.• Diagnosing congenital anomalies ..and

lastly evaluating a diseased kidney accordingly .