Variability Over Time of Normal-Sized Fetal Renal Pelvis During the Second Trimester Scan

Abstract

Purpose To investigate the variability of the normal-sized fetal renal pelvis (≤5 mm) over time and to analyze repeatability of measurements.

Materials and Methods 98 fetal renal pelvises and 49 fetal urinary bladders were analyzed at a gestational age of 17–20 weeks at St. Olavs Hospital, Trondheim, Norway. The anterior-posterior diameter (APD) of the fetal renal pelvis and two diameters of the fetal bladder were measured with an interval of at least 30 min. Intra- and interobserver variations and variations over time and in association with bladder size were investigated.

Results The mean difference in renal pelvis size between the first and second measurements was 0.09 mm (95% CI, −0.09 to 0.26 mm). The variation over time was ≤1 mm in 85% of cases and the renal pelvis was ≤4 mm in both the first and second examinations in 92% of cases. The intraclass correlation coefficient (ICC) was 0.54 (95% CI: 0.31 to 0.69). We did not observe any association between variation of bladder size and variation of APD. The difference in fetal renal pelvis size was ≤1 mm in 70% of observations for the first examiner and 58% for the second examiner. The intraobserver ICCs were 0.71 (95% CI: 0.62–0.78) and 0.60 (95% CI: 0.50–0.70) for the two observers respectively. The interobserver difference was ≤1 mm in 72% of cases and the interobserver ICC was 0.56 (95% CI: 0.34–0.71).

Conclusion The variation of the APD of the fetal renal pelvis over time was small in fetuses with the APD in the lower range and can mainly be explained by intraobserver variation.

Key words

bladder - pelvicaliceal - ureter

• References

• 1 Scott JE, Renwick M. Urological anomalies in the Northern Region Fetal Abnormality Survey. Arch Dis Child. 1993; 68: 22-26
• 2 Livera LN, Brookfield DS, Egginton JA, Hawnaur JM. Antenatal ultrasonography to detect fetal renal abnormalities: A prospective screening programme. BMJ 1989; 298: 1421-1423
• 3 Sairam S, Al-Habib A, Sasson S, Thilaganathan B. Natural history of fetal hydronephrosis diagnosed on mid-trimester ultrasound. Ultrasound Obstet Gynecol. 2001; 17: 191-196
• 4 Agathokleous M, Chaveeva P, Poon LC, Kosinski P, Nicolaides KH. Meta-analysis of second-trimester markers for trisomy 21. Ultrasound Obstet Gynecol. 2013; 41: 247-261
• 5 Cohen-Overbeek TE, Wijngaard-Boom P, Ursem NT, Hop WC, Wladimiroff JW, Wolffenbuttel KP. Mild renal pyelectasis in the second trimester: Determination of cut-off levels for postnatal referral. Ultrasound Obstet Gynecol. 2005; 25: 378-383
• 6 Coplen DE, Austin PF, Yan Y, Blanco VM, Dicke JM. The magnitude of fetal renal pelvic dilatation can identify obstructive postnatal hydronephrosis, and direct postnatal evaluation and management. J Urol. 2006; 176: 724-727 discussion 727
• 7 Corteville JE, Gray DL, Crane JP. Congenital hydronephrosis: correlation of fetal ultrasonographic findings with infant outcome. Am J Obstet Gynecol. 1991; 165: 384-388
• 8 Ouzounian JG, Castro MA, Fresquez M, al-Sulyman OM, Kovacs BW. Prognostic significance of antenatally detected fetal pyelectasis. Ultrasound Obstet Gynecol. 1996; 7: 424-428
• 9 Siemens DR, Prouse KA, MacNeily AE, Sauerbrei EE. Antenatal hydronephrosis: Thresholds of renal pelvic diameter to predict insignificant postnatal pelviectasis. Tech Urol 1998; 4: 198-201
• 10 Wollenberg A, Neuhaus TJ, Willi UV, Wisser J. Outcome of fetal renal pelvic dilatation diagnosed during the third trimester. Ultrasound Obstet Gynecol. 2005; 25: 483-488
• 11 Ismaili K, Hall M, Piepsz A, Alexander M, Schulman C, Avni FE. Insights into the pathogenesis and natural history of fetuses with renal pelvis dilatation. Eur Urol. 2005; 48: 207-214
• 12 Gramellini D, Fieni S, Caforio E, Benassi G, Bedocchi L, Beseghi U. et al. Diagnostic accuracy of fetal renal pelvis anteroposterior diameter as a predictor of significant postnatal nephrouropathy: Second versus third trimester of pregnancy. Am J Obstet Gynecol. 2006; 194: 167-173
• 13 Chitty LS, Altman DG. Charts of fetal size: Kidney and renal pelvis measurements. Prenat Diagn. 2003; 23: 891-897
• 14 van Vuuren SH, Damen-Elias HA, Stigter RH, van der Doef R, Goldschmeding R, de Jong TP. et al. Size and volume charts of fetal kidney, renal pelvis and adrenal gland. Ultrasound Obstet Gynecol. 2012; 40: 659-664
• 15 Persutte WH, Hussey M, Chyu J, Hobbins JC. Striking findings concerning the variability in the measurement of the fetal renal collecting system. Ultrasound Obstet Gynecol. 2000; 15: 186-190
• 16 Damen-Elias HA, Stigter RH, De Jong TP, Visser GH. Variability in dilatation of the fetal renal pelvis during a bladder filling cycle. Ultrasound Obstet Gynecol. 2004; 24: 750-755
• 17 Kusanovic JP, Nien JK, Goncalves LF, Espinoza J, Lee W, Balasubramaniam M. et al. The use of inversion mode and 3D manual segmentation in volume measurement of fetal fluid-filled structures: Comparison with Virtual Organ Computer-aided AnaLysis (VOCAL). Ultrasound Obstet Gynecol. 2008; 31: 177-186
• 18 Bland JM, Altman DG. Applying the right statistics: Analyses of measurement studies. Ultrasound Obstet Gynecol. 2003; 22: 85-93
• 19 Duin LK, Willekes C, Koster-Kamphuis L, Offermans J, Nijhuis JG. Fetal hydronephrosis: Does adding an extra parameter improve detection of neonatal uropathies?. J Matern Fetal Neonatal Med 2012; 25: 920-923
• 20 Pereira AK, Reis ZS, Bouzada MC, de Oliveira EA, Osanan G, Cabral AC. Antenatal ultrasonographic anteroposterior renal pelvis diameter measurement: Is it a reliable way of defining fetal hydronephrosis?. Obstet Gynecol Int 2011; 2011: 861865
• 21 Robinson JN, Tice K, Kolm P, Abuhamad AZ. Effect of maternal hydration on fetal renal pyelectasis. Obstet Gynecol. 1998; 92: 137-141
• 22 Valentin L, Bergelin I. Intra- and interobserver reproducibility of ultrasound measurements of cervical length and width in the second and third trimesters of pregnancy. Ultrasound Obstet Gynecol. 2002; 20: 256-262