Objective
To explore the value of renal parenchyma-to-hydronephrosis area ratio (PHAR) in detecting
trends of hydronephrosis (HN) improvement or worsening and response to surgical intervention.
Methods
Initial and follow-up sagittal renal ultrasound images of patients entered into a
prenatal HN database from 2008 to 2016, with baseline Society for Fetal Urology (SFU)
grades III and IV HN and without vesicoureteral reflux, were evaluated using National
Institutes of Health-sponsored image-processing software. Renal parenchymal area,
hydronephrosis area (HA), PHAR, anteroposterior diameter (APd), and SFU grade were
captured at baseline and most recent visit. Data were analyzed based on the need for
surgical intervention to address obstruction.
Results
Out of 193 infants (159 boys; 135 left side), 58 (30%) underwent surgery. Patients
managed surgically compared with those managed nonsurgically had worse baseline HN
severity markers: SFU grade (3.6 ± 0.5 vs 3.1 ± 0.4; P < .001), urinary tract dilation classification (2.7 ± 0.5 vs 2.2 ± 0.4; P < .001), APd (20.3 ± 10.1 vs 12.8 ± 8.0; P < .001), HA (10.0 ± 6.6 vs 4.7 ± 2.8; P < .001), and PHAR (1.3 ± 1.0 vs 3.0 ± 2.9; P < .001); but both patient groups had similar renal parenchymal area (9.4 ± 3.5 vs
9.7 ± 2.8; P = .5). At last follow-up, the following discrepancies persisted: SFU grade (2.3 ± 1.0
vs 1.7 ± 1.0; P < .001), urinary tract dilation classification (1.5 ± 0.7 vs 1.0 ± 0.7; P < .001), APd (11.7 ± 8.0 vs 7.7 ± 5.7; P < .001), and HA (6.4 ± 5.1 vs 3.6 ± 2.7; P < .001); however, PHAR was equalized for both groups (7.2 ± 14.0 vs 7.1 ± 6.1; P = .9).
Conclusion
By concurrently considering changes in renal parenchyma and degree of HN, we found
that PHAR appears to be a promising parameter that reflects similarities between patients
managed surgically and those managed nonsurgically, despite initial discrepancies.
Our data suggest that this variable may provide reassurance and a more objective assessment
of improvement after surgery compared with other traditional ultrasound outcome measures.
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to UrologyAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- The Society for Fetal Urology consensus statement on the evaluation and management of antenatal hydronephrosis.J Pediatr Urol. 2010; 6: 212-231https://doi.org/10.1016/j.jpurol.2010.02.205
- Ultrasonography of the hydronephrosis in newborn: a practical review.Ultrasonography. 2016; 35: 198-211https://doi.org/10.14366/usg.15073
- Antenatal hydronephrosis as a predictor of postnatal outcome: a meta-analysis.Pediatrics. 2006; 118: 586-593https://doi.org/10.1542/peds.2006-0120
- The fate of prenatally diagnosed primary nonrefluxing megaureter: do we have reliable predictors for spontaneous resolution?.Urology. 2008; 72: 309-312https://doi.org/10.1016/j.urology.2008.02.032
- The fate of primary nonrefluxing megaureter: a prospective outcome analysis of the rate of urinary tract infections, surgical indications and time to resolution.J Urol. 2016; 195: 1300-1305
- Diagnostic accuracy of renal pelvic dilatation for detecting surgically managed ureteropelvic junction obstruction.J Urol. 2013; 190: 661-666https://doi.org/10.1016/j.juro.2013.02.014
- Results of a practical protocol for management of prenatally detected hydronephrosis due to ureteropelvic junction obstruction.Pediatr Surg Int. 2009; 25: 61-67https://doi.org/10.1007/s00383-008-2294-6
- The predictive value of the first postnatal ultrasound in children with antenatal hydronephrosis.Int Braz J Urol. 2011; 37: 557https://doi.org/10.1590/S1677-55382011000400031
- Screening ultrasound in follow-up after pediatric pyeloplasty.Urology. 2010; 76: 175-179https://doi.org/10.1016/j.urology.2009.09.092
- Percent improvement in renal pelvis antero-posterior diameter (PI-APD): prospective validation and further exploration of cut-off values that predict success after pyeloplasty in children supporting safe monitoring with ultrasound alone.J Pediatr Urol. 2016; 12 (e1-6): 228https://doi.org/10.1016/j.jpurol.2016.04.003
- Radiation-free monitoring in the long-term follow-up of pyeloplasty: are ultrasound new parameters good enough to evaluate a successful procedure?.J Pediatr Urol. 2016; 12 (e1-7): 230https://doi.org/10.1016/j.jpurol.2016.04.026
- Pelvis/cortex ratio: an early marker of success following pyeloplasty in children.J Pediatr Urol. 2010; 6: 473-476https://doi.org/10.1016/j.jpurol.2009.12.004
- Mild to moderate postnatal hydronephrosis—grading systems and management.Nat Rev Urol. 2013; 10: 649-656
- Renal parenchymal area and risk of ESRD in boys with posterior urethral valves.Clin J Am Soc Nephrol. 2014; 9: 499-505https://doi.org/10.2215/CJN.08700813
- Predicting risk of chronic kidney disease in infants and young children at diagnosis of posterior urethral valves: initial ultrasound kidney characteristics and validation of parenchymal area as forecasters of renal reserve.J Urol. 2016; 196: 862-868https://doi.org/10.1016/j.juro.2016.03.137
- Evaluation of sonographic renal parenchymal area in the management of hydronephrosis.J Urol. 2001; 165: 548-551https://doi.org/10.1097/00005392-200102000-00066
- Renal parenchyma to hydronephrosis area ratio (PHAR) as a predictor of future surgical intervention for infants with high-grade prenatal hydronephrosis.Urology. 2016; https://doi.org/10.1016/j.urology.2016.09.029
- Sonographic renal parenchymal and pelvicaliceal areas: new quantitative parameters for renal sonographic followup.J Urol. 1996; 156: 725-729
- Perinatal urology renal parenchymal area growth curves for children 0 to 10 months old.J Urol. 2016; 195: 1203-1208
- The use of renal parenchymal area in children with high grade vesicoureteral reflux.J Urol. 1997; 158: 1232-1235https://doi.org/10.1016/S0022-5347(01)64438-0
- Ultrasound grading of hydronephrosis: introduction to the system used by the society for fetal urology.Pediatr Radiol. 1993; 23: 478-480https://doi.org/10.1007/BF02012459
- Multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system).J Pediatr Urol. 2014; 10: 982-998https://doi.org/10.1016/j.jpurol.2014.10.002
- Early postoperative ultrasound after open pyeloplasty in children with prenatal hydronephrosis helps identify low risk of recurrent obstruction.J Urol. 2012; 188: 2347-2353https://doi.org/10.1016/j.juro.2012.08.036
- NIH Image to ImageJ: 25 years of image analysis.Nat Methods. 2012; 9: 671-675https://doi.org/10.1038/nmeth.2089
- Is routine renography required after pyeloplasty?.J Urol. 2010; 184: 1128-1133https://doi.org/10.1016/j.juro.2010.05.017
- Long-term followup of pediatric dismembered pyeloplasty: how long is long enough?.J Urol. 2003; 169 (discussion 1812; author reply 1812): 1809-1812https://doi.org/10.1097/01.ju.0000055040.19568.ea
- National trends in followup imaging after pyeloplasty in children in the United States.J Urol. 2015; 194: 777-782https://doi.org/10.1016/j.juro.2015.03.123
- Reimplantation of obstructive megaureters with and without tailoring.J Pediatr Urol. 2006; 2: 178-181https://doi.org/10.1016/j.jpurol.2005.05.010
- Is long-term sonographic followup necessary after uncomplicated ureteral reimplantation in children?.J Urol. 2005; 174: 1429-1432https://doi.org/10.1097/01.ju.0000173128.73742.bc
- Segmentation of renal parenchymal area from ultrasound images using level set evolution.Conf Proc IEEE Eng Med Biol Soc. 2014; 2014: 4703-4706https://doi.org/10.1109/EMBC.2014.6944674
Article info
Publication history
Published online: January 19, 2017
Accepted:
January 11,
2017
Received:
October 23,
2016
Footnotes
Mandy Rickard, Armando J. Lorenzo, and Luis H. Braga contributed equally.
Financial Disclosure: The authors declare that they have no relevant financial interests.
Identification
Copyright
© 2017 Elsevier Inc. All rights reserved.
