2D-SWE examination
renal-axis, chronic kidney disease
CORTEX
Within two days prior to the renal biopsy procedure, a board-certified radiologist with over three years’ experience in abdominal elastography conducted a 2D-SWE examination on the patients. The radiologist was blinded to the information regarding the clinical and laboratory status of the patient. A 2D-SWE examination was conducted when patients lay supine on an US examination table using an Aixplorer US imaging system (Supersonic Imagine, Aixen-Provence, France) equipped with a SC6-1 broad band convex array probe (frequency: 1–6 MHz). In the 2D-SWE examination, participants were required to empty their bladders completely before the procedure and also hold their breath for a few seconds during the procedure. Measurements were performed in the right renal coronal plane, with the transducer parallel to the renal-axis view and without applying any physical pressure to the patient. In conventional US, the renal length (from the upper pole to the lower pole), renal parenchymal thickness (from the outer renal margin to the outer margin of the renal sinus), and renal inter-lobar artery resistive index (RI) were measured. A trapezium-shaped, color-coded elasticity image box measuring 4 × 3 cm was placed in the mid-region of the kidney. Then a circular region of interest (4 mm in diameter) was positioned inside the image box, primarily in the outer renal cortex, to obtain the maximum elastic value displayed (A representative example of shear wave elastography imaging (A) and histopathological analysis using various stainings (B-E). (A) A color-coded shear wave elastogram and a corresponding conventional ultrasound image of a patient with chronic kidney disease. Images of a 10× objective kidney biopsy stained with (B) hematoxylin-eosin stain, (C) Masson’s trichrome stain, (D) periodic acid-Schiff stain, and (E) methenamine silver stain taken from this patient.