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Society of Nuclear Medicine Procedure Guideline for
Diuretic Renography in Children
version 2.0, approved February 7, 1999
Authors: Gerald A. Mandell, MD (DuPont Hospital for Children, Wilmington, DE); Jeffrey A. Cooper, MD (Albany Med-ical Center, Albany, NY); Joe C. Leonard, MD (Oklahoma Children’s Memorial Hospital, Oklahoma City, OK); MassoudMajd, MD (Children’s National Medical Center, Washington, DC); John H. Miller, MD (Children’s Hospital Los Angeles,Los Angeles, CA); Marguerite T. Parisi, MD (Children’s Hospital Los Angeles, Los Angeles, CA); and George N.
Sfakianakis, MD, PhD (University of Miami School of Medicine, Miami, FL).
spontaneously and is related to physiologic changeduring early development. The diagnosis of ob- The purpose of this guideline is to assist nuclear struction often requires sequential scintigraphic ex- medicine practitioners in recommending, perform- ing, interpreting, and reporting the results of di-uretic renography in children.
III. Common Indications
II. Background Information and Definitions
A. Ureteropelvic or ureterovesical obstruction Hydronephrosis (distension of the pelvicalyceal sys- B . Prenatal ultrasound diagnosis of hydronephrosis tem) is one of the most common indications for ra- C. Post-surgical evaluation of a previously ob- dionuclide evaluation of the kidneys in pediatric pa- tients. The etiology of the hydronephrosis can be an D. Distension of pelvicalyceal system as an etiology obstructed renal pelvis, an obstructed ureter, vesi- coureteral reflux, the bladder itself or the bladderoutlet, infection or congenital in nature.
IV. Procedure
Contrast intravenous urography, ultrasonogra- phy and conventional radionuclide renography cannot reliably differentiate obstructive from nonob- 1. Preparation prior to arrival in department structive causes of hydronephrosis and hydroure- Preparation is usually not necessary. If the pa- teronephrosis (distension of the pelvicalyceal sys- tient is not going to receive intravenous flu- ids, oral hydration is encouraged prior to ar- The pressure perfusion study (Whitaker test), which measures collecting system pressure under conditions 2. Preparation prior to injection of the radio- of increased pelvic infusion, is relatively invasive.
The evaluation of function in the presence of ob- a. The procedure is explained to parents and struction does not give reliable indication of poten- all children old enough to understand.
tial for recovery following surgical correction. High b. Continual communication and reassurance pressure in the collecting system results in reduction with explanation of each step is essential for cooperation and successful intravenous The most common cause of unilateral obstruction is the presence of a ureteropelvic obstruction. Ob- structions can also occur more distally at the c. Oral hydration may be sufficient in certain ureterovesical junction. Bilateral hydronephrosis can situations. Intravenous hydration is more be produced by posterior urethral valves, bilateral reliable in the diagnosis of questionable ureteropelvic obstructions or even a full bladder.
The purpose of diuretic renography is to differen- tiate a true obstruction from a dilated nonobstructed to maintain sufficient hydration for a good system (stasis) by serial imaging after intravenous diuretic effect and obviate the necessity for administration of furosemide (Lasix).
Hydronephrosis detected in utero may resolve d . Bladder catheterization is not always nec- 4. An allergy to sulfa drugs may prevent usage of furosemide (cross reactivity between sulfa and furosemide) in a small percentage of pa- reliable with bladder catheterization.
tients. Urethral anesthesia with xylocaine Older children, who are not catheterized, should not be used in patients with an allergic are requested to void completely prior to history to lidocaine or its derivatives.
1. The examination table is covered with plastic- lined absorbent paper to contain spilled tracer and reduce contamination of the table during 2. Gentle catheterization by a qualified individ- painful experience and results in better coop- eration during follow-up examinations.
3. Slow, deep breathing and a gentle forward ii. Continual drainage by catheterization motion of the catheter should be used to relax 4. An application of urethral anesthesia (3 to 5 ml of lidocaine jelly) in the male urethra 2 to 5 min before catheterization helps decrease the iii. The diuretic effect can be assessed by 5. A Foley balloon is only inflated after catheter and its balloon are confirmed to be in the bladder. Urine return can be appreciated with balloon still positioned in the posterior ure- thra. The balloon must be deflated prior to re- e. The patient is usually hydrated intra- moval from the patient’s bladder. When a venously (10–15 ml/kg of D5 0.22% NS for feeding tube is used for bladder drainage, under 1 yr of age and D5 0.45% NS for over premeasurement of catheter length may pre- 1 yr of age) for thirty min prior to adminis- tering the diuretic. The slow administra- 6. Caution should be observed with postural tion of fluid is continued during the re- changes because of possible diuresis-induced f. If the rate of urine flow is low during hy- 7. Sudden abdominal or flank pain can arise dration, a larger amount of fluid (up to 40 during acute distension of the pelvicalyceal g. Some laboratories do not use intravenous 8. There is a small risk of catheter-induced hydration or catheter bladder drainage for the initial evaluation (particularly in older children) so that kidneys can be evaluated 1. Technetium-99m diethylene triamine pen- taacetic acid (Tc-99m DTPA) is a glomerular B. Information Pertinent to Performing the agent. The biological half life is under 2.5 hr.
95% of the administered dose is cleared by 1 . A prenatal history of urinary tract obstruction, history of prior surgery to the urinary tract 2. Tc-99m mercaptoacetyltriglycine (Tc-99m and congenital urinary abnormalities (duplex MAG3) is cleared by tubular secretion. After systems, renal fusion, etc.) are important for about three hr, 90% of the injected dose can be accurate interpretation of the study.
2 . The review of available past radiographic, ul- 3. Tc-99m MAG3 has a high initial renal uptake, trasound and radionuclide studies adds to the accuracy of interpretation of the current study.
with good temporal resolution. It is recom- 3. Nonlatex materials should be used in patients mended for neonatal renography and for vi- prone to latex allergy (e.g. congenital spinal sualization of kidneys in patients with com- defects and chronic urethral catheterization).
SOCIETY OF NUCLEAR MEDICINE PROCEDURE GUIDELINES MANUAL JUNE 2002 4. Iodine-131 orthoiodohippurate (OIH) (Hip- jected at 20 min or later after the radio- puran) is cleared by tubular excretion (80%) pharmaceutical (F + 20 or later) when the and glomerular filtration (20%) with ninety percent clearance in the first pass through the with several drops of potassium iodide oral 5. The minimal administered activity for Tc-99m b. In the method developed in Europe, the di- DTPA is about 20 MBq (0.5 mCi). The maxi- uretic is injected 15 min prior to the injec- mum administered activity for Tc-99m DTPA tion of the radiopharmaceutical (F–15) and imaging is continued for thirty min after the injection of the radiopharmaceutical.
6. The minimal administered activity for Tc-99m MAG3 is about 20 MBq (0.5 mCi). The maxi- 1 . The preliminary study is a dynamic renal scan mum administered activity for Tc-99m MAG3 with the patient supine with his/her back to the camera and acquisition for 20 to 30 min as serial 15 to 30 sec images (64 x 64 or 128 x 128 7. The minimal administered activity for I-131- matrix format). After the first few min, 30 to 60 OIH is about 1.0 MBq (0.025 mCi). The maxi-mum administered activity for I-131-OIH is sec images may be acquired. This format can be used for the pre-diuretic phase of F + 20 or 1. The dose of furosemide (Lasix) is 1.0 mg/kg 2. For the diuretic phase, the supine position permits the least motion and is recommended higher diuretic dose may be necessary in cases for infants and most children. The sitting po- sition is occasionally necessary but can result 2. There are two validated, but different ap- in motion, even in the most cooperative child.
proaches for the time of injection of the di- 3. The diuretic effect usually begins within 1 to 2 min after the administration of the diuretic.
a. In the method endorsed by the American 4. For the diuretic phase of F + 20 or later, con- Society of Fetal Urology, the diuretic is in- tinuous computer and analog acquisitions arebegun one to two min prior to the administra- Radiation Dosimetry in Children*
(5 year old)
Radiopharmaceutical
Administered Activity
Effective Dose+
Organ Receiving the
L a r g e s t Radiation Dose+
( m C i / k g )
*Treves ST. Pediatric Nuclear Medicine. 2nd Edition. Springer-Verlay, 1995, pp. 567-569.
+Per MBq (per mCi) tion of the diuretic (the baseline phase) and of the washout study has been used for differ- entiation of stasis from obstruction.
5. The computer is set to record 15 to 60 sec frames for the baseline phase and for the ad- 1. The procedure, date of the study, amount and ditional 30 min with a 64 x 64 or 128 x 128 ma- route of administration of the radiopharma- ceutical, and previous study for comparison 1. From the dynamic renal study, careful evalu- 2 . The history includes symptoms and/or di- ation of the parenchymal phase reveals renal function, size and position. Cortical transit 3. The technique includes catheter size and type time and dilatation of the collecting system if implemented, amount and kind of i.v. fluid are examined on the excretory phase.
if administered, the imaging sequence, the 2. Baseline images of the diuretic phase are used amount and time of diuretic administration, for the assessment of the diuretic effect.
and the urine volumes pre- and post-diuretic 3. Cinematic viewing of the diuretic phase as- sesses patient movement. If there is consider- 4. The findings may include renal perfusion, split renal function, progression of activity,and the T 1/ around the collecting systems of individual frames will have to be compared at various time intervals of the study to assess drainage.
There are no issues of quality control.
4. Regions of interest are drawn around the di- lated pelvicalyceal system for curve analysis 1. Infiltration of the radiopharmaceutical or di- and calculation of the T 1/2. One to two back- ground regions can also be drawn. The reader 2. Insufficient hydration can result in delayed is referred to a standardized technique of the uptake and excretion, simulating poor func- “well-tempered” diuretic renogram.
tion, or demonstrate a normal response in the 5. The diuretic half-time is the time at which the presence of significant obstruction.
time-activity curve decreases to half of its 3. If the diuretic is administered prior to the maximum distension of the collecting system, 6. Residual activity can be reported by estimat- the response may not reflect the true physio- ing the percentage of the initial tracer activity that remains at 30 min after the injection of the 4 . Poor renal function from prolonged severe ob- struction can result in slow tracer accumula- tion in the dilated collecting system and result 1. The diuretic effect usually begins within 1 to 2 in difficult interpretation of the diuretic phase.
min after the administration of the diuretic.
5. With severe compromise of function (less 2. In absence of obstruction, there is rapid and almost complete washout of the radiotracer.
furosemide (a tubular effect) may be difficult 3. Obstructed systems can result in delayed amount of activity proximal to the obstruction 6 . A large, unobstructed collecting system with relatively good renal function can exhibit slow 4 . With the injection of the diuretic after the ra- drainage of the radiotracer (prolonged T 1/2) .
diopharmaceutical (F + 20 or later), a T 1/2 l e s s 7. When the obstruction is at both pelvicalyceal than 10 min usually means the absence of ob- and ureterovesical junctions, it may be diffi- cult to detect the ureterovesical junction ob- struction. A repeat evaluation may need to be between 10 and 20 min is an equivocal result.
performed following the surgical correction of the ureteropelvic junction obstruction.
8 . Patient movement may invalidate curve 5. With the injection of the diuretic prior to the radiopharmaceutical (F–15), the T 1/2 greater 9. Urinary systems considered normal on the than 20 min is compatible with obstruction.
dynamic study should not be evaluated for 6. The shape of the resulting time activity curves drainage. A prolonged T 1/2 can be obtained SOCIETY OF NUCLEAR MEDICINE PROCEDURE GUIDELINES MANUAL JUNE 2002 because of the relatively small amount of Meller ST, Eckstein HB. Renal scintigraphy: quantitative residual activity in the collecting system to re- assessment of upper urinary tract dilatation in chil- d r e n . J Pediatr Surg 1 9 8 1 ; 1 6 : 1 2 3 – 1 2 6 .
Senac MO, Miller JH, Stanley P. Evaluation of obstruc- V. Issues Requiring Further Clarification
tive uropathy in children: radionuclide renographyversus the Whitaker test. AJR 1984;143:11–15.
A. The calculation method of the diuretic half-time Wackman J, Brewer E, Gelfand MJ, et al. Low grade is variable, but a standardized technique is avail- pelviureteric obstruction with normal diuretic renography. Br J Urol 1986;58:364–367.
B. The curve analysis has been questioned because Whitaker RH, Buxton TMS. A comparison of pressure of poor correlation with pressure perfusion stud- flow studies and renography in equivocal upper tract obstruction. J Urol 1 9 8 6 ; 1 3 1 : 4 4 6 – 4 4 9 .
C. The results of alternative method of simultane- ous injection of the radiopharmaceutical and di- Disclaimer
D. Guidelines for doses of Lasix above usual maxi- The Society of Nuclear Medicine has written and approved guidelines to promote the cost-effectiveuse of high quality nuclear medicine procedures.
VI. Concise Bibliography
These generic recommendations cannot be applied Conway JJ. Radionuclide cystography. In: Tauxe WN, to all patients in all practice settings. The guidelines Dubovsky EV, eds. Nuclear Medicine in Clinical should not be deemed inclusive of all proper proce- Urology and Nephrology. East Norwalk, CT: Apple- dures or exclusive of other procedures reasonably ton, Century & Crofts; 1985:305–320.
directed to obtaining the same results. The spec- Conway JJ. “Well-tempered” diuresis renography: its trum of patients seen in a specialized practice set- historical development, physiological and technical ting may be quite different than the spectrum of pa- pitfalls, and standardized technique protocol. Sem tients seen in a more general practice setting. The appropriateness of a procedure will depend in part Foda MM, Garfield CT, Matzinger M, et al. A prospec- on the prevalence of disease in the patient popula- tive randomized trial comparing 2 diuresis renog- tion. In addition, the resources available to care for raphy techniques for evaluation of suspected upper patients may vary greatly from one medical facility urinary tract obstruction in children. J Urol to another. For these reasons, guidelines cannot be Kass EJ, Majd M. Evaluation and management of the Advances in medicine occur at a rapid rate. The upper urinary tract obstruction in infancy and date of a guideline should always be considered in childhood. Urol Clin NA 1985;12:122–141.
determining its current applicability.

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