RENAL ANATOMY MEDULLA RENAL CORTEX RENAL COLUMN MAJOR CALYCES RENAL PELVIS RENALURETER CAPSULE MINOR CALYX RENAL MEDULLARY PYRAMID
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)
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
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 .