Keywords:
Dilatation, Developmental disease, Cystography / Uretrography, Contrast agent-other, Ultrasound, Urinary Tract / Bladder, Ultrasound physics, Contrast agents
Authors:
M. Skender, I. Jurca, I. Sjekavica; Zagreb/HR
DOI:
10.1594/ecr2018/C-0665
Methods and materials
Consecutive patients who underwent CeVUS between March 2017 and September 2017 were included in this retrospective study.
All patients were admitted to hospital for one-day hospitalization and observed for several hours in the cases of adverse effects to the contrast agent.
Every patient received a four-day scheme antibiotic prophylaxis—the first dose on the day of the procedure,
and the next three doses the following three days.
The indications for the procedure were urinary tract infections; follow-up in patients with previously diagnosed VUR; postoperative follow-up and pre/postnatal detection of hydronephrosis or urinary tract anomalies.
The exclusion criteria were a positive urine culture and febrility.
The urine culture was routinely obtained to rule out UTI tendency.
All the procedures were performed with the same ultrasound machine (Logiq E9,
GE) using a convex array transducer (1-5MHz) for B-mode and contrast enhanced imaging ('true agent detection mode').
The brightness (gain) was adjusted from 18 to 22 and the mechanical index (MI) was set to 0.15.
A second-generation ultrasound contrast agent (SonoVue,
Bracco) was used.
In addition to the ultrasound machine with dedicated software and the ultrasound contrast agent,
a normal saline,
a urinary catheter,
and an infusion system were necessary for performing the procedure ( Fig. 1 ).
The procedure began with pre-contrast ultrasound B-mode scans of the urinary tract to analyze the anatomy,
measuring kidney sizes,
and taking note of potential abnormal findings.
Then the urinary bladder was catheterized and emptied so that the ultrasound contrast agent (0.8-1ml) diluted with normal saline (100-250 ml) could be intravesically administered via a transurethral catheter.
We calculated the expected urinary bladder capacity for each patient using standard formulas (patients > 1 year old Volume = (age in years +2) ×30 ml; patients < 1 year old Volume = 10ml/kg) to obtain optimal bladder distension.
The administration of the contrast agent and normal saline as well as voiding were carried out under US monitoring using contrast mode imaging.
The procedure was considered successful when we manage to fill the urinary bladder with a sufficient amount of fluid (normal saline with contrast agent) and when the patient managed to void on the table.
The results were considered positive when contrast microbubbles were seen in the ureter or within the kidney collecting system.
A VUR grade of 0 to 5 was assigned according to the International System of Radiologic Grading of Vesicoureteral Reflux: Grade 0 indicates no VUR; grade 1,
VUR limited to the ureter; grade 2,
VUR extending to the renal pelvis without dilatation; grade 3,
VUR extending to the kidney with mild ureteral dilatation and mild-to-moderate pelvicalyceal dilatation; grade 4,
VUR extending to the kidney with moderate ureteral dilatation and complete obliteration of the sharp angles of all fornices; and grade 5,
VUR extending to the kidney with a tortuous ureter and moderate dilatation of the renal pelvis to extreme dilatation of the entire upper urinary tract.
(Fig. 2 )