ARFI evaluation of the kidneys in ex premature infants: a preliminary study

Transcription

1 ARFI evaluation of the kidneys in ex premature infants: a preliminary study Poster No.: C-1556 Congress: ECR 2015 Type: Authors: Keywords: DOI: Scientific Exhibit C. Bruno, A. Bucci, M. Zaffanello, R. Pozzi-Mucelli; Verona/IT Kidney, Paediatric, Elastography, Diagnostic procedure, Congenital /ecr2015/C-1556 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 14

2 Aims and objectives It is known from the Literature that prematurity, together with low birth weight, is associated with hypertension, cardiovascular events and impaired renal function; a possible explanation is due to the fact that- together with prematurity - it has been linked to low glomerular number, high glomerular size and thus progressive susceptibility to renal disease in adulthood. Since ARFI is under evaluation to establish its role in the workout of chronic kidney disease, the aim of this report is to describe if any relationship exists, in the school-aged children, between prematurity and US and ARFI findings. Page 2 of 14

3 Methods and materials PATIENTS 20 patients born preterm (gestational age: 28.5+/-3.3 W; age range: 8+/-1.1 ys) (Table 1 on page 4) were compared with 20 healthy controls (Table 2 on page 4). Patients who received potentially nephrotoxic drugs were excluded from the study. US EVALUATION For each kidney length and volume (using the ellipsoid formula) were measured. Patients during measurements were breathold and in lateral decubitus, with kidneys evaluated with subcostal approach. ARFI EVALUATION A mean SWV was calculated for each kidney; it was obtained from nine measurements obtained respectively at the upper, at the middle and at the lower third (Fig. 1 on page 4). All measurements were obtained with the ROI lying parallel to the US main beam. When evaluating upper and lower third the imaging plan was axial, when evaluating the middle third it was used a sagittal plan. An overall SWV for the two kidneys was also calculated from the average of the mean SWV of the two kidneys. The statistical significance of the difference found between the two groups was evaluated by means of the Mann-Whitney test. Data were also expressed using the "box and whiskers plot" in order to describe the variability of measurements. Page 3 of 14

4 Images for this section: Table 1: US and ARFI findings in kidneys of ex pre term children at the school age. Table 2: US and ARFI findings of healthy Patients at school age. Page 4 of 14

5 Fig. 1: ARFI evaluation of the right kidney in an healthy Patient. The ROI is positioned in the cortex, parallel to the main US beam, with a sub costal approach. Since measurements are taken at the middle third, a sagittal scan is used. Page 5 of 14

6 Results US EVALUSTION Non statistically significant difference was found between the two groups when considering the length of the two kidneys (Fig. 2 on page 7) and the volume as well (Fig. 3 on page 7). ARFI EVALUATION Kidneys of ex premature Patients showed an higher SWV (Fig. 4 on page 8) than healthy subjects (Fig. 5 on page 9) (3.02+/-0.60 m/sec vs.2.56+/-0.37 m/sec; P <0.01); the difference existing between the SWV of left kidneys between the two groups was statistically significant too (3.30+/-0.66 m/sec vs /-0.27 m/sec; p<0.01) (Fig. 6 on page 10). No statistical significant difference was found between the SWV of the right kidneys of the two groups (2.70+/-0.65 m/sec vs /-0.51) (Fig. 6 on page 10). Page 6 of 14

7 Images for this section: Fig. 2: "Box and whiskers" plot showing the difference existing between healthy Patients and ex premature Patients when considering the length of the two kidneys. The difference was not statistically significant. Page 7 of 14

8 Fig. 3: "Box and whiskers" plot showing the difference existing between healthy Patients and ex premature Patients when considering the volume of the two kidneys. The difference was not statistically significant. Page 8 of 14

9 Fig. 4: ARFI evaluation of the left kidney in an ex premature Patient. Measurements are taken at the middle third, with the patient lying on the ipsilateral decubitus and with a subcostal approach. Page 9 of 14

10 Fig. 5: ARFI evaluation of the right kidney in an ex premature Patient. Measurements are taken at the middle third, with the patient lying on the ipsilateral decubitus and with a subcostal approach. Values are lower than values measured in fig 4. Fig. 6: "Box and whiskers" plot showing the difference existing between healthy Patients and ex premature Patients when considering the SWV. Statistically significant difference is found between the mean SWV of the two kidneys and between the SWV of the left ones. Page 10 of 14

11 Conclusion Prematurity is associated to a statistically significant difference in the overall SWV of the two kidneys probably reflecting an early damage due to the reduced number of nephrons present at birth. Although, at school age, no statistically significant difference was found when considering length and volume, a statistically significant difference was found in the ARFI measurements (an emerging technique in the evaluation of parenchymal stiffness) when evaluating the mean values of the two kidneys. The meaning of the difference existing between right and left kidneys in ex premature Patients is actually under investigation. Page 11 of 14

12 Personal information Page 12 of 14

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14 11) Puddu M, Fanos V, Podda F, Zaffanello M. The kidney from prenatal to adult life: perinatal programming and reduction of number of nephrons during development. Am J Nephrol. 2009;30(2): ) Rakow A,Johansson S,Legnevall L,Sevastik R,Celsi G,Norman M,Vanpée M. Renal volume and function in school-age children born preterm or small for gestational age. Pediatr Nephrol Aug;23(8): ) Stock KF, Klein BS, Cong MT, Regenbogen C, Kemmner S, Büttner M, Wagenpfeil S, Matevossian E, Renders L, Heemann U, Küchle C. ARFI-based tissue elasticity quantification and kidney graft dysfunction: first clinical experiences. Clin Hemorheol Microcirc. 2011;49(1-4): ) Yildirim H, Gungor S, Cihangiroglu MM, Aygun AD. Doppler studies in normal kidneys of preterm and term neonates: changes in relation to gestational age and birth weight. J Ultrasound Med May;24(5): Nightingale, Curr Med Imaging Rev 2011 Page 14 of 14