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IS LONG-TERM SONOGRAPHIC FOLLOWUP NECESSARY AFTER UNCOMPLICATED URETERAL REIMPLANTATION IN CHILDREN?
0022-5347/05/1744-1429/0 THE JOURNAL OF UROLOGY® Copyright © 2005 by AMERICAN UROLOGICAL ASSOCIATION
Vol. 174, 1429 –1432, October 2005 Printed in U.S.A.
DOI: 10.1097/01.ju.0000173128.73742.bc
IS LONG-TERM SONOGRAPHIC FOLLOWUP NECESSARY AFTER UNCOMPLICATED URETERAL REIMPLANTATION IN CHILDREN? STEPHEN G. CHARBONNEAU, LESLIE D. TACKETT, EILEEN HODGE GRAY, RICHARD E. CAESAR AND ANTHONY A. CALDAMONE*,† From the Tulane University School of Medicine, New Orleans, Louisiana (SGC), and Division of Pediatric Urology, Brown University School of Medicine, Hasbro Children’s Hospital, Providence, Rhode Island
ABSTRACT
Purpose: We examined the necessity of postoperative ultrasound following surgical correction of vesicoureteral reflux beyond initial postoperative assessment. The followup among children who have undergone correction of vesicoureteral reflux has varied, and currently there are no standards to document how long postoperative monitoring for hydronephrosis, renal scarring or renal growth should continue. Materials and Methods: The study population included 128 children who underwent surgical correction of primary vesicoureteral reflux between 1992 and 2002. Data were collected as part of a retrospective chart review and included age at surgery, preoperative grade of reflux, indications for surgery, type of surgical correction, postoperative voiding cystourethrogram and ultrasound results, and postoperative course relative to urinary tract infections, incontinence and other symptoms. Results: Of 128 patients 4 had postoperative reflux on voiding cystourethrogram. In each of these cases reflux either resolved completely or remained stable during postoperative followup. A total of 17 patients had grade 2 or 3 hydronephrosis on the initial 3-month postoperative ultrasound. In all of these cases hydronephrosis remained stable or improved during followup. In no case was there evidence of development of new hydronephrosis or worsening of previously established hydronephrosis beyond the 1-year postoperative ultrasound. Conclusions: Our data indicate that followup of uncomplicated ureteral reimplantation in children more than 1 year postoperatively is not warranted. The elimination of studies beyond 1 year following surgery would result in a significant cost savings. KEY WORDS: vesico-ureteral reflux, cystostomy, pediatrics, postoperative period, ultrasonography
Vesicoureteral reflux is one of the most common urological abnormalities. The surgical correction of reflux has been shown to have a high success rate.1 However, wide variation exists on the recommended followup after reimplantation.2 At this time there are no documented guidelines as to how long upper tract surveillance should be conducted postoperatively to monitor for hydronephrosis, renal scarring or renal growth.3 To justify postoperative imaging, a defined benefit must be evident. The purpose of this study was to examine the necessity and costs of postoperative ultrasound after surgical correction of vesicoureteral reflux beyond the initial postoperative assessment. MATERIALS AND METHODS
The medical records of 128 patients who underwent ureteroneocystostomy at our institution between 1992 and 2002 were retrospectively reviewed. Patients who underwent ureteral tapering as well as those with duplicated systems were included in the study population, while those with a neurogenic bladder, outlet obstruction or other anatomical abnormality, such as ureterocele, were excluded. Patients with dysfunctional voiding diagnosed by history were also excluded from the study population. Age at surgery, preoperative grade of reflux, indications for surgery, technique of
surgical correction, postoperative voiding cystourethrogram (VCUG) and ultrasound results, and postoperative course with respect to urinary tract infections, incontinence and other symptoms were recorded. These data were then evaluated to determine the extent to which long-term sonographic followup might prove beneficial to the patient. RESULTS
The study population consisted of 103 females and 25 males, and included the entire cohort of ureteral reimplantations meeting inclusion criteria performed at this institution during the specified period. Average patient age was 4.6 years (range 8 months to 18 years). Mean postoperative followup was 39 months, and average number of postoperative ultrasounds was 3.3, including the immediate postoperative ultrasound conducted at 3 to 4 months after reimplantation. As is our standard practice, we obtained the initial postoperative ultrasound at 3 months, since it is likely that most postoperative edema and transient hydronephrosis have resolved by then. All 128 patients in the study population underwent postoperative ultrasound at 1 year and annually thereafter for a variable period, and none of the ultrasounds after the initial 3 months revealed new onset hydronephrosis. A total of 111 patients underwent bilateral ureteral reimplantation and 17 underwent unilateral reimplantation. Among the patients 87 underwent intravesical reimplantation and 41 underwent extravesical reimplantation. A total of 12 patients had a ureteral stent placed intraoperatively. Included in our data were 8 patients who had the ureter ta-
Submitted for publication January 14, 2005. Study received institutional review board approval. * Correspondence: Division of Pediatric Urology, Brown University School of Medicine, 2 Dudley St., Suite 174, Providence, Rhode Island 02905. † Financial interest and/or other relationship with Mentor and Bioform. 1429
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LONG-TERM SONOGRAPHIC FOLLOWUP AFTER URETERAL REIMPLANTATION IN CHILDREN
pered. Although this is a limited number of patients, no patient demonstrated reflux on postoperative VCUG or new onset hydronephrosis on postoperative ultrasound. The only difference in the treatment of those patients whose ureters were tapered is that all of them underwent postoperative VCUG, and this continues to be our practice. A total of 19 patients in the study population had a duplicated system. None of these patients went on to have postoperative reflux or new onset hydronephrosis. Surgical correction of reflux was undertaken for persistent vesicoureteral reflux (101 patients), breakthrough urinary tract infections during prophylactic antibiotic treatment (37) and noncompliance with antibiotics (4). Some of the patients in the study population had more than 1 reason for undergoing surgical correction of reflux. Of the patients 12 had documented renal scarring before ureteral reimplantation based on dimercapto-succinic acid (DMSA) scan. Not all of the patients in the study population underwent preoperative DMSA scan, as this is not a standard part of our evaluation of patients with vesicoureteral reflux without any indication, such as scarring on ultrasound or multiple episodes of pyelonephritis. A total of 111 patients underwent postoperative voiding cystourethrography and 17 did not, as a number of studies have shown that obtaining a postoperative VCUG after uncomplicated ureteral reimplantation may be unnecessary due to the extremely high success rate of ureteroneocystostomy.1, 4 –7 The reason such a large percentage (86.7%) of our patient population underwent VCUG postoperatively is that a large portion of our data were gathered before publication of these studies. Of the 111 patients who underwent VCUG persistent vesicoureteral reflux was noted in 4 (3.6%, see table). Three of these patients exhibited ipsilateral reflux on VCUG, while 1 had development of contralateral reflux. Five patients had grade 1 hydronephrosis and 11 had grade 2 or 3 hydronephrosis on the initial 3-month ultrasound. In all of these cases hydronephrosis remained stable or improved during followup of up to 6 years. In no case was there evidence of the development of new hydronephrosis or worsening of previously established hydronephrosis beyond the 1-year postoperative ultrasound. None of the patients in the study population had development of ureteral obstruction postoperatively. A postoperative renogram was ordered only if there was hydronephrosis greater than expected on the initial postoperative ultrasound based on the degree of reflux.8 Only 1 patient in the study population underwent a postoperative DMSA scan, which revealed that renal function was stable. A postoperative DMSA scan was not ordered without indications, such as new scarring on ultrasound or multiple episodes of pyelonephritis. DISCUSSION
At this time there is no consensus on appropriate followup among children who have undergone ureteral reimplantation. The Pediatric Vesicoureteral Reflux Guidelines Panel summary report did not address the issue of followup after uncomplicated ureteral reimplantation.3 Herndon et al reported a survey sent out to all members of the American
Patient characteristics No. Pts Bilat reimplantation Unilat reimplantation Duplicated systems Tapered ureters Postop status: Reflux Hydronephrosis
111 17 19 8 4 16
Academy of Pediatrics Section on Urology, which contained questions on the medical and surgical followup of patients with vesicoureteral reflux, and demonstrated that there is wide variation regarding recommended followup after reimplantation, ranging from no postoperative visits or studies to followup into adulthood.2 They noted that early evaluation of the upper tracts by ultrasound appears appropriate but suggested that one could argue against multiple postoperative imaging. The data from our study seem to support this argument. The usefulness of any imaging modality is predicated on the fact that it must improve the quality of care for the patient or monitor for significant risk. Despite the fact that ultrasound is a noninvasive procedure, it is certainly not without cost in terms of monetary expense and inconvenience to patients and their families. The results of our study suggest that long-term sonographic followup after ureteral reimplantation does not have a significant role in the postoperative treatment of patients who have undergone uncomplicated ureteral reimplantation and have had an uncomplicated postoperative course. There is an emerging trend to use postoperative imaging more selectively. There are studies suggesting that obtaining a postoperative voiding cystourethrogram after uncomplicated ureteral reimplantation is unnecessary, given the extremely high success rate of this operation in the hands of competent surgeons.1, 4 –7 A previous collaborative study at our institution showed that due to the high success rate of ureteral reimplantation and the benign course of patients with persistent low grade postoperative reflux, there is little need to perform postoperative VCUG in patients who have undergone uncomplicated ureteral reimplantation.6 Grossklaus et al concluded that it is unnecessary to document surgical success with postoperative VCUG in asymptomatic patients with a normal ultrasound examination.7 However, they state that they continue to obtain voiding cystourethrograms in those patients with a postoperative febrile urinary tract infection or recurrent cystitis. They also recommend continued use of ultrasound to monitor all patients after ureteral reimplantation, although they do not specify the length of time that upper tract surveillance is necessary. They argue that ultrasound is noninvasive and does not expose the child to radiation. At our institution the cost of renal ultrasound is $642, and the cost of pelvic ultrasound is $696. The radiology fees for interpreting these studies are $125 for renal ultrasound and $140 for pelvic ultrasound. Thus, the annual cost of followup for each patient who undergoes renal and pelvic ultrasound is $1,603 per study. Although these costs are specific to our institution, they should remain fairly constant across different regions. Bisignani and Decter stated that eliminating postoperative VCUG after reimplantation would result in a cost savings of $2.8 million annually.1 Using their numbers of approximately 230 pediatric urologists in this country, with each performing approximately 20 reimplantations annually, eliminating sonographic followup beyond 1 year postoperatively in cases of uncomplicated ureteral reimplantation could possibly result in a cost savings in excess of $7 million annually in this country. The time and inconvenience to the patient and his or her family of obtaining multiple ultrasounds after uncomplicated ureteral reimplantation are also factors that are difficult to measure but cannot be discounted. There have been few studies addressing postoperative ultrasound specifically. In a report by Bomalaski et al the records of 167 patients who had undergone ureteroneocystostomy were reviewed.5 They found that in patients with no risk factors for postoperative vesicoureteral reflux or hydronephrosis, such as abnormal preoperative ultrasound or dysfunctional voiding, further postoperative imaging may be unnecessary. In this study dysfunctional voiding was found
LONG-TERM SONOGRAPHIC FOLLOWUP AFTER URETERAL REIMPLANTATION IN CHILDREN
to be the greatest risk factor for postoperative vesicoureteral reflux, and the authors concluded that only patients with no voiding or elimination problems should be considered for limited postoperative imaging. However, as the authors also acknowledge, it has been firmly established that there is a wide range of normal voiding behaviors in children,9 and, thus, predicting which children might benefit from further sonographic followup could be a difficult task. Vesicoureteral reimplantation is an operation with low but significant risk, and certainly early postoperative evaluation of the upper tracts is necessary. Complications such as obstruction, contralateral reflux and persistent postoperative reflux occur.10 Although this study has certain limitations, such as the fact that it is retrospective and there was not a uniform followup pattern, our results support our hypothesis that long-term sonographic followup does not seem to lead to any changes in the postoperative treatment of patients with these complications in the absence of postoperative symptoms. Thus, despite the fact that these complications arise in a small percentage of children who undergo vesicoureteral reimplantation, long-term sonographic followup seems to add little to the postoperative management of these cases.
CONCLUSIONS
Surgical correction of vesicoureteral reflux remains highly successful. Our data indicate that followup of uncomplicated pediatric cases of ureteral reimplantation beyond 1 year postoperatively is not warranted. The 1-year point was chosen arbitrarily. However, it seems a reasonable timeline to allow for proper healing as well as an adequate period of observation to watch for the development of new problems. After 1 year these patients can be discharged from followup with the understanding that if any symptoms such as pyelonephritis arise, they need to return. The elimination of studies beyond 1 year postoperatively would result in a significant cost savings.
REFERENCES
1. Bisignani, G. and Decter, R. M.: Voiding cystourethrography after uncomplicated ureteral reimplantation in children: is it necessary? J Urol, 158: 1229, 1997 2. Herndon, C. D. A., Ferrer, F. A. and McKenna, P. H.: Survey results on medical and surgical followup of patients with vesicoureteral reflux from American Association of Pediatrics, Section on Urology members. J Urol, 165: 559, 2001 3. Elder, J. S., Peters, C. A., Arant, B. S., Jr., Ewalt, D. H., Hawtrey, C. E., Hurwitz, R. S. et al: Pediatric Vesicoureteral Reflux Guidelines Panel summary report on the management of primary vesicoureteral reflux in children. J Urol, 157: 1846, 1997 4. Barrieras, D., Lapointe, S., Reddy, P. P., Williot, P., McLorie, G. A., Bagli, D. et al: Are postoperative studies justified after extravesical ureteral reimplantation? J Urol, 164: 1064, 2000 5. Bomalaski, M. D., Ritchey, M. L. and Bloom, D. A.: What imaging studies are necessary to determine outcome after ureteroneocystostomy? J Urol, 158: 1226, 1997 6. Lavine, M. A., Siddiq, F. M., Cahn, D. J., Caesar, R. E., Koyle, M. A. and Caldamone, A. A.: Vesicoureteral reflux after ureteroneocystostomy: indications for postoperative voiding cystography. Tech Urol, 7: 50, 2001 7. Grossklaus, D. J., Pope, J. C., Adams, M. C. and Brock, J. W.: Is postoperative cystography necessary after ureteral reimplantation? Urology, 58: 1041, 2001 8. Lebowitz, R. L.: Postoperative Pediatric Uroradiology. New York: Appleton-Century-Crofts, p. 19, 1981 9. Bloom, D. A., Seeley, W. W., Ritchey, M. L. and McGuire, E. J.: Toilet habits and continence in children: an opportunity sampling in search of normal parameters. J Urol, 149: 1087, 1993 10. Hoenig, D. M., Diamond, D. A., Rabinowitz, R. and Caldamone, A. A.: Contralateral reflux after unilateral ureteral reimplantation. J Urol, 156: 196, 1996
1431
EDITORIAL COMMENT The most devastating complication after ureteral implantation surgery is partial or complete obstruction of the ureter. In comparison, persistent reflux is really only an issue that hurts the surgeon’s pride. There is little trial evidence to show a benefit of surgical correction of reflux,1 and it is vital that no harm is caused. If ureteral obstruction occurs on average in 1 case per 100, then the chances of completing a series of 140 cases without seeing an obstruction are about 24% (99140/100140). This is not statistically unlikely. To answer the question, “How long do we need to follow children with ultrasound after ureter reimplantation?” it would have been better to look at children who had development of ureteral obstruction postoperatively to see when the obstruction developed and when it was diagnosed. These cases are rare, so this type of study is much more difficult and will only be possible using data collected across institutions. Obstruction is more likely to occur in patients with abnormal bladder, for example in neurogenic bladder and in severe dysfunctional voiding. The authors excluded patients when this diagnosis was made preoperatively. However, in some cases dysfunctional voiding only becomes apparent in the postoperative period. For example some children undergo surgery before toilet training and have development of dysfunctional voiding only after toilet training. So perhaps ultrasound followup is required beyond completion of toilet training. In children who are beyond toilet training perhaps surveillance is not required after 6 months or even after 3 months. None of the ultrasounds in this series changed for the worse after the 3-month studies. Perhaps the initial followup should occur before 3 months. If an obstruction develops, then there would be little renal function left to salvage by 3 months. In experimental animals a partly obstructed kidney can only regain function if the obstruction is relieved before 6 weeks. A completely obstructed kidney loses salvageable function after 10 days. In the European arm of the International Reflux Study there were 10 patients (4.2%) with development of ureteral obstruction, of whom 6 had development of new scarring on excretory urography. Only 7 of these 10 patients needed reoperation, so some obstructions seem to settle without reoperation but still cause renal damage. One of the quoted benefits of surgical correction of reflux is that the reflux is cured and the patient can be discharged from medical care or at least the investigations can be minimized. It is important to know whether this can be safely done, and there is certainly doubt at present.2 I commend the authors for giving us further evidence to help with this decision. Grahame Smith Childrens Hospital at Westmead Sydney, Australia 1. Wheeler, D., Vimalachandra, D., Hodson, E. M., Roy, L. P., Smith, G. and Craig, J. C.: Antibiotics and surgery for vesicoureteric reflux: a meta-analysis of randomised controlled trials. Arch Dis Child, 88: 688, 2003 2. Mor, Y., Leibovitch, I., Zalts, R., Lotan, D., Jonas, P. and Ramon, J.: Analysis of the long-term outcome of surgically corrected vesico-ureteric reflux. BJU Int, 92: 97, 2003 REPLY BY AUTHORS Obstruction is fortunately quite rare after routine ureteral reimplantation and is more likely to occur in the abnormal bladder, be it neurologically abnormal or functionally abnormal. The purpose of our study was to evaluate the incidence of ureteral obstruction in the clinically normal bladder to identify the population in which the postoperative followup can be tapered safely. It has been shown in other series that many cases of failed ureteral reimplantation due to persistent reflux or obstruction had occult voiding dysfunction.1 Therefore, we agree that it would be prudent to follow these patients through toilet training even in the absence of any symptomatology. However, for those who are already toilet trained and present with no clinical complications, a followup as short as 1 year appears safe based on the data provided in our study. The Mor study cited in our article, on the other hand, taught us that patients who have successful ureteral reimplantation may still have recurrent urinary tract infection and its consequences. It did not address whether these patients are prone to ureteral obstruction.
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LONG-TERM SONOGRAPHIC FOLLOWUP AFTER URETERAL REIMPLANTATION IN CHILDREN
Intrinsic tendency towards urinary tract infections, despite successful reflux surgery, has been demonstrated in other series as well to persist into pregnancy as well.2,3 It is important for surgeons to caution patients and parents alike that antireflux surgery does not eliminate urinary tract infections per se. 1. Noe, N. H.: The role of dysfunctional voiding in failure or complication of ureteral reimplantation for primary reflux. J Urol, 134: 1172, 1985
2. Mansfield, J. T., Snow, B. W., Cartwright, P. C. and Wadsworth, K.: Complications of pregnancy in women after childhood reimplantation for vesicoureteral reflux: an update with 25 years of followup. J Urol, 154: 787, 1995 3. Bukowski, T. P., Betrus, G. G., Aquilina, J. W. and Perlmutter, A. D.: Urinary tract infections and pregnancy in women who underwent antireflux surgery in childhood. J Urol, 159: 1286, 1998
Vol. 174, 1429 –1432, October 2005 Printed in U.S.A.
DOI: 10.1097/01.ju.0000173128.73742.bc
IS LONG-TERM SONOGRAPHIC FOLLOWUP NECESSARY AFTER UNCOMPLICATED URETERAL REIMPLANTATION IN CHILDREN? STEPHEN G. CHARBONNEAU, LESLIE D. TACKETT, EILEEN HODGE GRAY, RICHARD E. CAESAR AND ANTHONY A. CALDAMONE*,† From the Tulane University School of Medicine, New Orleans, Louisiana (SGC), and Division of Pediatric Urology, Brown University School of Medicine, Hasbro Children’s Hospital, Providence, Rhode Island
ABSTRACT
Purpose: We examined the necessity of postoperative ultrasound following surgical correction of vesicoureteral reflux beyond initial postoperative assessment. The followup among children who have undergone correction of vesicoureteral reflux has varied, and currently there are no standards to document how long postoperative monitoring for hydronephrosis, renal scarring or renal growth should continue. Materials and Methods: The study population included 128 children who underwent surgical correction of primary vesicoureteral reflux between 1992 and 2002. Data were collected as part of a retrospective chart review and included age at surgery, preoperative grade of reflux, indications for surgery, type of surgical correction, postoperative voiding cystourethrogram and ultrasound results, and postoperative course relative to urinary tract infections, incontinence and other symptoms. Results: Of 128 patients 4 had postoperative reflux on voiding cystourethrogram. In each of these cases reflux either resolved completely or remained stable during postoperative followup. A total of 17 patients had grade 2 or 3 hydronephrosis on the initial 3-month postoperative ultrasound. In all of these cases hydronephrosis remained stable or improved during followup. In no case was there evidence of development of new hydronephrosis or worsening of previously established hydronephrosis beyond the 1-year postoperative ultrasound. Conclusions: Our data indicate that followup of uncomplicated ureteral reimplantation in children more than 1 year postoperatively is not warranted. The elimination of studies beyond 1 year following surgery would result in a significant cost savings. KEY WORDS: vesico-ureteral reflux, cystostomy, pediatrics, postoperative period, ultrasonography
Vesicoureteral reflux is one of the most common urological abnormalities. The surgical correction of reflux has been shown to have a high success rate.1 However, wide variation exists on the recommended followup after reimplantation.2 At this time there are no documented guidelines as to how long upper tract surveillance should be conducted postoperatively to monitor for hydronephrosis, renal scarring or renal growth.3 To justify postoperative imaging, a defined benefit must be evident. The purpose of this study was to examine the necessity and costs of postoperative ultrasound after surgical correction of vesicoureteral reflux beyond the initial postoperative assessment. MATERIALS AND METHODS
The medical records of 128 patients who underwent ureteroneocystostomy at our institution between 1992 and 2002 were retrospectively reviewed. Patients who underwent ureteral tapering as well as those with duplicated systems were included in the study population, while those with a neurogenic bladder, outlet obstruction or other anatomical abnormality, such as ureterocele, were excluded. Patients with dysfunctional voiding diagnosed by history were also excluded from the study population. Age at surgery, preoperative grade of reflux, indications for surgery, technique of
surgical correction, postoperative voiding cystourethrogram (VCUG) and ultrasound results, and postoperative course with respect to urinary tract infections, incontinence and other symptoms were recorded. These data were then evaluated to determine the extent to which long-term sonographic followup might prove beneficial to the patient. RESULTS
The study population consisted of 103 females and 25 males, and included the entire cohort of ureteral reimplantations meeting inclusion criteria performed at this institution during the specified period. Average patient age was 4.6 years (range 8 months to 18 years). Mean postoperative followup was 39 months, and average number of postoperative ultrasounds was 3.3, including the immediate postoperative ultrasound conducted at 3 to 4 months after reimplantation. As is our standard practice, we obtained the initial postoperative ultrasound at 3 months, since it is likely that most postoperative edema and transient hydronephrosis have resolved by then. All 128 patients in the study population underwent postoperative ultrasound at 1 year and annually thereafter for a variable period, and none of the ultrasounds after the initial 3 months revealed new onset hydronephrosis. A total of 111 patients underwent bilateral ureteral reimplantation and 17 underwent unilateral reimplantation. Among the patients 87 underwent intravesical reimplantation and 41 underwent extravesical reimplantation. A total of 12 patients had a ureteral stent placed intraoperatively. Included in our data were 8 patients who had the ureter ta-
Submitted for publication January 14, 2005. Study received institutional review board approval. * Correspondence: Division of Pediatric Urology, Brown University School of Medicine, 2 Dudley St., Suite 174, Providence, Rhode Island 02905. † Financial interest and/or other relationship with Mentor and Bioform. 1429
1430
LONG-TERM SONOGRAPHIC FOLLOWUP AFTER URETERAL REIMPLANTATION IN CHILDREN
pered. Although this is a limited number of patients, no patient demonstrated reflux on postoperative VCUG or new onset hydronephrosis on postoperative ultrasound. The only difference in the treatment of those patients whose ureters were tapered is that all of them underwent postoperative VCUG, and this continues to be our practice. A total of 19 patients in the study population had a duplicated system. None of these patients went on to have postoperative reflux or new onset hydronephrosis. Surgical correction of reflux was undertaken for persistent vesicoureteral reflux (101 patients), breakthrough urinary tract infections during prophylactic antibiotic treatment (37) and noncompliance with antibiotics (4). Some of the patients in the study population had more than 1 reason for undergoing surgical correction of reflux. Of the patients 12 had documented renal scarring before ureteral reimplantation based on dimercapto-succinic acid (DMSA) scan. Not all of the patients in the study population underwent preoperative DMSA scan, as this is not a standard part of our evaluation of patients with vesicoureteral reflux without any indication, such as scarring on ultrasound or multiple episodes of pyelonephritis. A total of 111 patients underwent postoperative voiding cystourethrography and 17 did not, as a number of studies have shown that obtaining a postoperative VCUG after uncomplicated ureteral reimplantation may be unnecessary due to the extremely high success rate of ureteroneocystostomy.1, 4 –7 The reason such a large percentage (86.7%) of our patient population underwent VCUG postoperatively is that a large portion of our data were gathered before publication of these studies. Of the 111 patients who underwent VCUG persistent vesicoureteral reflux was noted in 4 (3.6%, see table). Three of these patients exhibited ipsilateral reflux on VCUG, while 1 had development of contralateral reflux. Five patients had grade 1 hydronephrosis and 11 had grade 2 or 3 hydronephrosis on the initial 3-month ultrasound. In all of these cases hydronephrosis remained stable or improved during followup of up to 6 years. In no case was there evidence of the development of new hydronephrosis or worsening of previously established hydronephrosis beyond the 1-year postoperative ultrasound. None of the patients in the study population had development of ureteral obstruction postoperatively. A postoperative renogram was ordered only if there was hydronephrosis greater than expected on the initial postoperative ultrasound based on the degree of reflux.8 Only 1 patient in the study population underwent a postoperative DMSA scan, which revealed that renal function was stable. A postoperative DMSA scan was not ordered without indications, such as new scarring on ultrasound or multiple episodes of pyelonephritis. DISCUSSION
At this time there is no consensus on appropriate followup among children who have undergone ureteral reimplantation. The Pediatric Vesicoureteral Reflux Guidelines Panel summary report did not address the issue of followup after uncomplicated ureteral reimplantation.3 Herndon et al reported a survey sent out to all members of the American
Patient characteristics No. Pts Bilat reimplantation Unilat reimplantation Duplicated systems Tapered ureters Postop status: Reflux Hydronephrosis
111 17 19 8 4 16
Academy of Pediatrics Section on Urology, which contained questions on the medical and surgical followup of patients with vesicoureteral reflux, and demonstrated that there is wide variation regarding recommended followup after reimplantation, ranging from no postoperative visits or studies to followup into adulthood.2 They noted that early evaluation of the upper tracts by ultrasound appears appropriate but suggested that one could argue against multiple postoperative imaging. The data from our study seem to support this argument. The usefulness of any imaging modality is predicated on the fact that it must improve the quality of care for the patient or monitor for significant risk. Despite the fact that ultrasound is a noninvasive procedure, it is certainly not without cost in terms of monetary expense and inconvenience to patients and their families. The results of our study suggest that long-term sonographic followup after ureteral reimplantation does not have a significant role in the postoperative treatment of patients who have undergone uncomplicated ureteral reimplantation and have had an uncomplicated postoperative course. There is an emerging trend to use postoperative imaging more selectively. There are studies suggesting that obtaining a postoperative voiding cystourethrogram after uncomplicated ureteral reimplantation is unnecessary, given the extremely high success rate of this operation in the hands of competent surgeons.1, 4 –7 A previous collaborative study at our institution showed that due to the high success rate of ureteral reimplantation and the benign course of patients with persistent low grade postoperative reflux, there is little need to perform postoperative VCUG in patients who have undergone uncomplicated ureteral reimplantation.6 Grossklaus et al concluded that it is unnecessary to document surgical success with postoperative VCUG in asymptomatic patients with a normal ultrasound examination.7 However, they state that they continue to obtain voiding cystourethrograms in those patients with a postoperative febrile urinary tract infection or recurrent cystitis. They also recommend continued use of ultrasound to monitor all patients after ureteral reimplantation, although they do not specify the length of time that upper tract surveillance is necessary. They argue that ultrasound is noninvasive and does not expose the child to radiation. At our institution the cost of renal ultrasound is $642, and the cost of pelvic ultrasound is $696. The radiology fees for interpreting these studies are $125 for renal ultrasound and $140 for pelvic ultrasound. Thus, the annual cost of followup for each patient who undergoes renal and pelvic ultrasound is $1,603 per study. Although these costs are specific to our institution, they should remain fairly constant across different regions. Bisignani and Decter stated that eliminating postoperative VCUG after reimplantation would result in a cost savings of $2.8 million annually.1 Using their numbers of approximately 230 pediatric urologists in this country, with each performing approximately 20 reimplantations annually, eliminating sonographic followup beyond 1 year postoperatively in cases of uncomplicated ureteral reimplantation could possibly result in a cost savings in excess of $7 million annually in this country. The time and inconvenience to the patient and his or her family of obtaining multiple ultrasounds after uncomplicated ureteral reimplantation are also factors that are difficult to measure but cannot be discounted. There have been few studies addressing postoperative ultrasound specifically. In a report by Bomalaski et al the records of 167 patients who had undergone ureteroneocystostomy were reviewed.5 They found that in patients with no risk factors for postoperative vesicoureteral reflux or hydronephrosis, such as abnormal preoperative ultrasound or dysfunctional voiding, further postoperative imaging may be unnecessary. In this study dysfunctional voiding was found
LONG-TERM SONOGRAPHIC FOLLOWUP AFTER URETERAL REIMPLANTATION IN CHILDREN
to be the greatest risk factor for postoperative vesicoureteral reflux, and the authors concluded that only patients with no voiding or elimination problems should be considered for limited postoperative imaging. However, as the authors also acknowledge, it has been firmly established that there is a wide range of normal voiding behaviors in children,9 and, thus, predicting which children might benefit from further sonographic followup could be a difficult task. Vesicoureteral reimplantation is an operation with low but significant risk, and certainly early postoperative evaluation of the upper tracts is necessary. Complications such as obstruction, contralateral reflux and persistent postoperative reflux occur.10 Although this study has certain limitations, such as the fact that it is retrospective and there was not a uniform followup pattern, our results support our hypothesis that long-term sonographic followup does not seem to lead to any changes in the postoperative treatment of patients with these complications in the absence of postoperative symptoms. Thus, despite the fact that these complications arise in a small percentage of children who undergo vesicoureteral reimplantation, long-term sonographic followup seems to add little to the postoperative management of these cases.
CONCLUSIONS
Surgical correction of vesicoureteral reflux remains highly successful. Our data indicate that followup of uncomplicated pediatric cases of ureteral reimplantation beyond 1 year postoperatively is not warranted. The 1-year point was chosen arbitrarily. However, it seems a reasonable timeline to allow for proper healing as well as an adequate period of observation to watch for the development of new problems. After 1 year these patients can be discharged from followup with the understanding that if any symptoms such as pyelonephritis arise, they need to return. The elimination of studies beyond 1 year postoperatively would result in a significant cost savings.
REFERENCES
1. Bisignani, G. and Decter, R. M.: Voiding cystourethrography after uncomplicated ureteral reimplantation in children: is it necessary? J Urol, 158: 1229, 1997 2. Herndon, C. D. A., Ferrer, F. A. and McKenna, P. H.: Survey results on medical and surgical followup of patients with vesicoureteral reflux from American Association of Pediatrics, Section on Urology members. J Urol, 165: 559, 2001 3. Elder, J. S., Peters, C. A., Arant, B. S., Jr., Ewalt, D. H., Hawtrey, C. E., Hurwitz, R. S. et al: Pediatric Vesicoureteral Reflux Guidelines Panel summary report on the management of primary vesicoureteral reflux in children. J Urol, 157: 1846, 1997 4. Barrieras, D., Lapointe, S., Reddy, P. P., Williot, P., McLorie, G. A., Bagli, D. et al: Are postoperative studies justified after extravesical ureteral reimplantation? J Urol, 164: 1064, 2000 5. Bomalaski, M. D., Ritchey, M. L. and Bloom, D. A.: What imaging studies are necessary to determine outcome after ureteroneocystostomy? J Urol, 158: 1226, 1997 6. Lavine, M. A., Siddiq, F. M., Cahn, D. J., Caesar, R. E., Koyle, M. A. and Caldamone, A. A.: Vesicoureteral reflux after ureteroneocystostomy: indications for postoperative voiding cystography. Tech Urol, 7: 50, 2001 7. Grossklaus, D. J., Pope, J. C., Adams, M. C. and Brock, J. W.: Is postoperative cystography necessary after ureteral reimplantation? Urology, 58: 1041, 2001 8. Lebowitz, R. L.: Postoperative Pediatric Uroradiology. New York: Appleton-Century-Crofts, p. 19, 1981 9. Bloom, D. A., Seeley, W. W., Ritchey, M. L. and McGuire, E. J.: Toilet habits and continence in children: an opportunity sampling in search of normal parameters. J Urol, 149: 1087, 1993 10. Hoenig, D. M., Diamond, D. A., Rabinowitz, R. and Caldamone, A. A.: Contralateral reflux after unilateral ureteral reimplantation. J Urol, 156: 196, 1996
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EDITORIAL COMMENT The most devastating complication after ureteral implantation surgery is partial or complete obstruction of the ureter. In comparison, persistent reflux is really only an issue that hurts the surgeon’s pride. There is little trial evidence to show a benefit of surgical correction of reflux,1 and it is vital that no harm is caused. If ureteral obstruction occurs on average in 1 case per 100, then the chances of completing a series of 140 cases without seeing an obstruction are about 24% (99140/100140). This is not statistically unlikely. To answer the question, “How long do we need to follow children with ultrasound after ureter reimplantation?” it would have been better to look at children who had development of ureteral obstruction postoperatively to see when the obstruction developed and when it was diagnosed. These cases are rare, so this type of study is much more difficult and will only be possible using data collected across institutions. Obstruction is more likely to occur in patients with abnormal bladder, for example in neurogenic bladder and in severe dysfunctional voiding. The authors excluded patients when this diagnosis was made preoperatively. However, in some cases dysfunctional voiding only becomes apparent in the postoperative period. For example some children undergo surgery before toilet training and have development of dysfunctional voiding only after toilet training. So perhaps ultrasound followup is required beyond completion of toilet training. In children who are beyond toilet training perhaps surveillance is not required after 6 months or even after 3 months. None of the ultrasounds in this series changed for the worse after the 3-month studies. Perhaps the initial followup should occur before 3 months. If an obstruction develops, then there would be little renal function left to salvage by 3 months. In experimental animals a partly obstructed kidney can only regain function if the obstruction is relieved before 6 weeks. A completely obstructed kidney loses salvageable function after 10 days. In the European arm of the International Reflux Study there were 10 patients (4.2%) with development of ureteral obstruction, of whom 6 had development of new scarring on excretory urography. Only 7 of these 10 patients needed reoperation, so some obstructions seem to settle without reoperation but still cause renal damage. One of the quoted benefits of surgical correction of reflux is that the reflux is cured and the patient can be discharged from medical care or at least the investigations can be minimized. It is important to know whether this can be safely done, and there is certainly doubt at present.2 I commend the authors for giving us further evidence to help with this decision. Grahame Smith Childrens Hospital at Westmead Sydney, Australia 1. Wheeler, D., Vimalachandra, D., Hodson, E. M., Roy, L. P., Smith, G. and Craig, J. C.: Antibiotics and surgery for vesicoureteric reflux: a meta-analysis of randomised controlled trials. Arch Dis Child, 88: 688, 2003 2. Mor, Y., Leibovitch, I., Zalts, R., Lotan, D., Jonas, P. and Ramon, J.: Analysis of the long-term outcome of surgically corrected vesico-ureteric reflux. BJU Int, 92: 97, 2003 REPLY BY AUTHORS Obstruction is fortunately quite rare after routine ureteral reimplantation and is more likely to occur in the abnormal bladder, be it neurologically abnormal or functionally abnormal. The purpose of our study was to evaluate the incidence of ureteral obstruction in the clinically normal bladder to identify the population in which the postoperative followup can be tapered safely. It has been shown in other series that many cases of failed ureteral reimplantation due to persistent reflux or obstruction had occult voiding dysfunction.1 Therefore, we agree that it would be prudent to follow these patients through toilet training even in the absence of any symptomatology. However, for those who are already toilet trained and present with no clinical complications, a followup as short as 1 year appears safe based on the data provided in our study. The Mor study cited in our article, on the other hand, taught us that patients who have successful ureteral reimplantation may still have recurrent urinary tract infection and its consequences. It did not address whether these patients are prone to ureteral obstruction.
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LONG-TERM SONOGRAPHIC FOLLOWUP AFTER URETERAL REIMPLANTATION IN CHILDREN
Intrinsic tendency towards urinary tract infections, despite successful reflux surgery, has been demonstrated in other series as well to persist into pregnancy as well.2,3 It is important for surgeons to caution patients and parents alike that antireflux surgery does not eliminate urinary tract infections per se. 1. Noe, N. H.: The role of dysfunctional voiding in failure or complication of ureteral reimplantation for primary reflux. J Urol, 134: 1172, 1985
2. Mansfield, J. T., Snow, B. W., Cartwright, P. C. and Wadsworth, K.: Complications of pregnancy in women after childhood reimplantation for vesicoureteral reflux: an update with 25 years of followup. J Urol, 154: 787, 1995 3. Bukowski, T. P., Betrus, G. G., Aquilina, J. W. and Perlmutter, A. D.: Urinary tract infections and pregnancy in women who underwent antireflux surgery in childhood. J Urol, 159: 1286, 1998