Cross fused renal ectopia

Case contributed by Marwan A. AlShaikh Husain


Known case of crossed-fused ectopia, referred to assess renal cortical function and to rule out renal cortical scar.

Patient Data

Age: 10 years
Gender: Male

Empty left renal fossa. Both kidneys are slightly malrotated, fused with each other and are visualized within the right iliac fossa (cross fused ectopia). No renal calculi, cysts or hydronephrosis is seen. 

Nuclear medicine

Right kidney is well-outlined in its anatomical position with homogeneous radiotracer distribution all over the imaged renal cortical tissue. No renal cortical scar.

Left kidney is not seen in its anatomical position and is seen across the midline towards the right kidney (cross fused ectopia) with the upper two thirds of the medial portion of the kidney appears in close contact with the medial portion of right kidney. It appears malrotated and smaller in size than the normally located right kidney. Photon-deficient area is seen in upper pole of crossed-fused ectopic kidney likely secondary to hydronephrosis. Differentiation renal function: Right kidney 69%, left kidney 31%.

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