Comparison Between Photofluorography and Standard Fluoroscopic
Voiding Cystourethrography in Evaluating Vesicoureteral Reflux in
Children With Urinary Tract Infection
Seid Ali Alamdaran 1, Mitra Naseri 2*, Ali Beheshtian 3
1 Radiology Department, Dr Sheikh Children hospital, Mashhad University of Medical Sciences, Mashhad, IR Iran
2 Pediatric Nephrology Departments, Dr Sheikh Children hospital, Mashhad University of Medical Sciences, Mashhad, IR Iran
3 Mashhad University of Medical Sciences, Mashhad, IR Iran
Nephro-Urol Mon. 2012;4(3): 541-544. DoI: 10.5812/numonthly.3562
A R T I C L E I N F OA B S T R A C T
Received: 19 Nov 2011
Revised: 27 Nov 2011
Accepted: 13 Dec 2011
Please cite this paper as:
Alamdaran SA, Naseri M, Beheshtian A. Comparison Between Photofluorography and Standard Fluoroscopic Voiding Cystoure-
thrography in Evaluating Vesicoureteral Reflux in Children With Urinary Tract Infection. Nepro-Urol Mon;4(3): 541-4. DoI: 10.5812/
Implication for health policy/practice/research/medical education:
This study is useful for pediatrist and radiologists.
Background: Imaging of the urinary system is considered to be responsible for signifi-
cant radiation in children.
Objectives: This study was conducted to measure and compare the radiation dose in
spot films with photofluorography voiding cystourethrography (VCUG) in children.
Patients and Methods: 111 [222 Kidney Urinary Unit (KUU)] pediatric patients, aged 1
month to 5 years, with symptomatic urinary tract infection were enrolled in the study.
Peak tube voltage (kVp), exposure setting (mAs), focus film distance (FFD), film size and
DAP (after the exam) were recorded for all patients. To evaluate the validity of the pho-
tographs, we calculated sensitivity, specificity, predictive values and agreement between
the two methods using the kappa statistic. If the kappa was greater than 0.75, between
0.4–0.75 or less than 0.4, then the agreement was excellent, good or poor, respectively. P
values less than 0.05 were statistically significant.
Results: Vesicoureteral reflux (VUR) was detected in 74 KUU (33.3%) in standard films and
in 71 (32%) in photographic images. The photographs had no false positives and 3 false
negatives. Therefore, the new method had a sensitivity of 96%, a specificity of 100%, a
negative predictive value of 98% and a positive predictive value of 100%. The two-method
agreement in the VUR diagnosis for grades 1, 4, 5 and the overall grading were excellent
(kappa > 0.83); however, for grades 2 and 3, agreement was 80%, which was good (kappa
Conclusions: our study suggests that the high validity and excellent agreement of the
photofluorography method in the diagnosis and grading of VUR, which is comparable
to spot films and represents a 50%–90% reduction in radiation, makes it the preferred
Copyright c 2012 Kowsar Corp. All rights reserved.
* Corresponding author: Mitra Naseri, Pediatric Nephrology Department,
Dr Sheikh Children hospital, Mashhad University of Medical Sciences,
Mashhad, IR Iran. Tel: +98-51172690215, +98-9151141639, Fax: +98-5117277470,
E-mail: Naserim@mums.ac.ir, firstname.lastname@example.org
Copyright c2012 Kowsar Corp. All rights reserved.
In the 11th Report on Carcinogens of the United States
National Toxicology program, X-irradiation and ionizing
irradiation were placed on the list of known human car-
cinogens (1). Imaging of the urinary system is considered
Nephro-Urol Mon. 2012;4(3)
Photofluorography vs. Fluoroscopic VCUG
Alamdaran SA et al.
responsible for about one-quarter of the genetically sig-
nificant radiation exposure in children. At present, the
gold standard for diagnosis and grade determination of
vesicoureteral reflux (VUR) is fluoroscopic voiding cysto-
urethrography (VCUG) with spot films because of its ac-
ceptable sensitivity and negative predictive value (2-4).
In addition to demonstrating anatomic abnormalities
of the urinary tract, the examination provides a physi-
ological means of detecting and characterizing VUR. It
is estimated that the incidence of urinary tract infection
(UTI) during childhood is 8% in girls and 2% in boys (5). The
amount of ionizing radiation delivered to a child during
a VCUG examination is less than that delivered during
other commonly performed pediatric examinations that
involve ionizing radiation, such as computed tomogra-
phy. Nevertheless, diagnostic information combined with
minimal radiation exposure is a constant concern when
employing radiographic techniques, especially in chil-
dren. According to AlARA concept, radiation exposure
during VCUG should be kept to a minimum. The AlARA
concept is especially important in children because their
rapidly developing tissues and organs are approximately
10 times more sensitive to ionizing radiation than middle-
aged adults (6).
Conventional fluoroscopy employs a relatively large
radiation dose, and approximately 25% of the genetically
significant radiation dose in children arises from imaging
of the urinary tract. Generally, the fluoroscopic dose is es-
timated to be 80% of the entire radiation dose in a VCUG
We guess that photofluorography with hard copy im-
ages without using spot film would result in a diagnostic
quality comparable to that of standard fluoroscopic VCUG
for detection of VUR in childhood UTI. The benefit of this
method may be lower radiation doses.
This study was conducted to measure and compare ra-
diation doses in spot films with photofluorography VCUG
3. Patients and Methods
Data were collected from the pediatric radiology depart-
ment of an academic center (Dr. Sheikh Children’s hospi-
tal, Mashhad University of Medical Sciences). The enrolled
population included 111 (222 KUU) pediatric patients, aged
1 month to 5 years (mean 2 years and 4 months), with
histories of documented symptomaticUTI. Urinary tract
infection was defined as growth of more than 100,000
colony-forming units/ml of one microorganism in cul-
tured urine. Urine samples were obtained by mid-stream
collection (toilet-trained patients) or urine bags (non-
toilet trained patients). Radiographic parameters, such
as peak tube voltage (kVp), exposure setting (mAs), focus
film distance (FFD), film size and DAP (after the exam),
were recorded. Based on NRPB recommendations, there
were only minor differences between the DAPs of the 1and
5-year-old groups (7). Therefore, patients under 5 years of
age with UTI who were referred for VCUG were studied.
All studies were performed on an Appelem Radiography/
DAPs were recorded in units of mGycm2 using an 841-c
meter (Gammex), which is specifically sensitive enough
for pediatric studies. our fluoroscopy unit has a 3.2 mm
aluminum equivalent total filtration, and the FFD was
110 cm for all patients, which was operated at 63–75 kVp,
depending on the size of the patient. An image intensi-
fier television chain was used for fluoroscopy, and a Sony
CRs 105 mm camera was used to document most of the
imaging. It should be noted that computed radiography
(CR) (Agfa and Radlink Sony printers) was used for all ex-
aminations. Due to the fact that this equipment was newly
installed in the department, so for both CR, the radiogra-
phers used the same settings for the VCUG examination.
The dose area product (DAP) is measured with an ion-
ization chamber mounted directly to the light beam dia-
phragm housing. The DAP is defined as the absorbed ra-
diation dose to air (or the air KERMA) averaged over the
area of the X-ray beam in a plane perpendicular to the
beam axis, multiplied by the area of the beam in the same
plane. It is usually expressed in Gycm2 and is conveniently
measured with special large-area ionization chambers
(DAP meters) attached to the diaphragm housing of the
X-ray tube, which intercepts the entire cross section of the
beam. The meter device measures the total diagnostic DAP
during radiography and fluoroscopy. This meter provides
real time DAP measurements as well as total dose mea-
surements. The values obtained with the DAP meter cor-
respond to the absorbed skin dose over a specified surface
area, reported as DAP. Measurements were done with both
systems for conventional spot film and photofluorogra-
Thermoluminescent dosimeters (TlDs) were prepared
in plastic sachets and then used for monitoring expo-
sure to the hands of parents who were asked to hold their
child steady. We also used TlDs for background radiation
measurements. Each sachet was labeled for left and right
hands. ESD was measured directly by liF:Mg,Ti thermo-
luminescent dosimeters (type TlD-100). Two TlDs were
placed inside plastic sachets and attached to the skin on
the back of the parents’ hands. The mean value for the
two calculated ESDs was used as the measured dose in the
hands. The TlD-100 liF chips were annealed by heating at
400°C for 1 h, cooled slowly to ambient temperature and
then reheated to 75°C and kept at that temperature for 18
h. These chips were then read using a harshaw 3500 TlD
The amount of contrast media solution (30%) to be in-
fused into the bladder was determined by predicting
bladder capacity, which was estimated in milliliters using
the following formulas: for children younger than 1 year,
Nephro-Urol Mon. 2012;4(3)
Photofluorography vs. Fluoroscopic VCUG
Alamdaran SA et al.
capacity = weight (kg) × 7; and for those older than 1 year,
capacity = (age (y) + 2 )× 30). We modified the VCUG proto-
col (two photofluorography spot films of the urinary sys-
tem during voiding in two left posterior and right poste-
rior oblique positions). The parents helped to tabilize and
support the children and catheter. We trained the parents
to help and prevent undesired voiding by pushing or
closing the children ’s external genitalia by their hands.
Each study consisted of 3 to 4 digital radiographic films
and synchronous fluoroscopic images printed on glossy
paper. We had two types of images for comparison, radio-
graphic spot images on film and identical paper images.
Photographic and spot radiographic images were then
interpreted by two independent radiologists with at least
3 years of experience. For dosimetry, we chose 30 patients
to compare radiation doses in both methods. These re-
ports were collected and statistically analyzed using the
appropriate tests from the SPSS 13 software package. To
evaluate the validity of the photography, we calculated
sensitivity, specificity, predictive values and agreement of
two methods using the kappa statistic. Kappa greater than
0.75, between 0.4–0.75 or less than 0.4 were considered as
excellent, good and poor, respectively. P values < 0.05 were
reported as statistically significant.
We analyzed 222 KUU (kidney urinary unit) reports for
presence or absence of VUR and its grading in spot films
(the gold standard) and photofluorography images. As a
result, reflux was seen in 74 KUU (33.3%) in standard films
and 71 (32%) in photographic images. The photographs
had no false positives, wherase it had 3 false negatives re-
sults. According to our results the new method had a sen-
sitivity, specificity, negative and positive predictive values
of 96%, 100%, 98% and 100% respectively. The two-method
agreement in the VUR diagnosis in grades 1, 4 and 5 and
the overall grading were excellent (kappa > 0.83). how-
ever, in grades 2 and 3, the agreement was 80%, which was
defined as good (kappa = 0.64).
In one case, the photography graded it higher (2→3) than
standard spot films, and in seven patients, the photogra-
phy graded it lower (3→2). In addition, the agreement in
the diagnosis of VUR between the 2 radiologists 'reports
was 100%, and the agreement in grading was 89% (kappa
= 0.77 :excellen). Table 1 compares the results of the DAP
values between the two methods. AS Table 2 shows DAP in
photofluorography was lower than in spot film and the
radiation dose increased based on body size. The parent’s
hands were also within 2–25 cm of the main beam. Accord-
ing to our results, the radiation doses received by the par-
ents were at background radiation levels.
There is a strong association between UTI and VUR in
children and VUR is a main risk factor for renal scarring
and renal failure in children. hence, early diagnosis of
urological anomalies mainly VUR is necessary to prevent
late omplications of UTI in children. In assessing and
grading vesicoureteral reflux, fluoroscopic VCUG with
spot film is the current gold standard method; however,
high radiation doses, especially with non-digital and non-
pulsed fluoroscopes, are a problem. Studies have shown
that elimination of spot film (i.e., digital or computer-
based video frame fluoroscopy, the capture and delivery of
fluoroscopic images to monitors or hard copies) reduces
the radiation dose by 40%–60% (8-12).
In the course of time with development equipment of
radiation systems, all searches directed to reduce radia-
tion dose, especially in children (most sensitive and more
life expanse for effect of radiation), without reducing the
sensivity of method. very articles have shown that 50% or
more portion of radiation belong to spot films (5, 8, 11, 12).
Photofluorography is a new modified method that uses
printed-paper images from a fluoroscope without the
need for spot films.
In our study, the agreement and grade of the VUR diag-
nosis were excellent, and the sensitivity and negative pre-
dictive values were high. In addition, the reliability of the
photographic images was high. The reliability was proba-
bly due to the significant agreement between the 2 radiol-
ogist reports in this study and the reports from other stud-
ies. The study probability could be repeated with the same
results, and thus repeatability was high (10). The results of
this study show that VCUG with photofluorography hard
Patient, No.Age Group, y Weight, kg, mean Spot Film DAP, mGycm2
Photofluorography DAP, mGycm2
9 0 < 16.4 56.2510.75
21 1–5 12.297.1311.38
Table 1. DAPa of the VCUG a Data for the Two Methods (Spot Film and Photofluorography)
a Abbreviations: DAP, dose area product; VCUG, voiding cystourethrography
Age Groups, yWeight, kgAlmen and Mattsson
et al. (15)
et al. (13)
phy (This Study)
0 < 1< 10- 0.170.3 0.04–2.480.050.01
aAbbreviations: DAP, dose area product; VCUG, voiding cystourethrography
10 < 201.4 0.150.8 0.10–1.470.09 0.01
Table 2. Comparison of DAPa Values from This Study and VCUG a Standard in other Studies (DAP Unit is Gycm2)
544 Download full-text
Nephro-Urol Mon. 2012;4(3)
Photofluorography vs. Fluoroscopic VCUG
Alamdaran SA et al.
copy has a high diagnostic value with very low radiation
doses (50%–90% reduction in radiation dose). In order to
achieve quality paper images (photofluorography), we
must be careful to regulate the contrast, brightness and
sharpness of the fluoroscopic monitor and printer. how-
ever, we must accept the fact that the quality and resolu-
tion of paper images and photographs are lower than
those of images on radiographic spot films, but they can-
not influence the VUR diagnosis or determine its grade.
The comparison of DAP values obtained in this study
with those taken from the literature is shown in Table 2. As
this table demonstrates, our values are lower than those
achieved by other studies. This is due to three issues: the
equipment, the examination method and the non-use of
fluoroscopy. DAP values from spot films are comparable
with the Persliden results (13); this may be related to the
use of computed radiography in our study and digital ra-
diology in the Persliden study. on the other hand, our re-
sults were lower than the Almen and Mattsson studies and
lower than the DRl (Diagnostic Reference levels) in the
UK. This is due to the use of the film-screen combination
by the Almen, Mattsson (14) and UK studies. When com-
paring the values of this study with those of other studies,
it is evident that the digital unit delivers lower radiation
however, the authors did state that there was no signifi-
cant difference in the interpretation of the images be-
tween the two types of images. The result of the present
study supports this statement. Therefore, this study sug-
gests that standard VCUG for reflux diagnosis and grad-
ing can be replaced with the photographic method. The
outcome of this study shows that the examination tech-
nique in pediatric radiology is not yet optimized and that
the non-optimized procedures contribute to considerable
variations in radiation doses for children. According to
our results, the radiation doses received by the parents
were similar to background levels. The results could have
been improved by using more sensitive TlDs, such as cal-
cium sulfate TlDs, for measuring radiation to the parent’s
hands because they are approximately 30 times more sen-
sitive than (liF) TlDs.
Although the doses received in fluoroscopy are lower
than the dose equivalent limit recommended for the gen-
eral public, exposure should be kept to a minimum, follow-
ing the AlARA principle. however, the risk versus benefit
of each radiograph is important and must be considered
carefully, especially since radiation effects are cumulative.
The results of this study show that standard VCUG for re-
flux diagnosis and grading can be replaced with the pho-
tographic method without spot films, although further
studies using the same design are warranted. Quantitative
methods for the assessment of patient doses should be
implemented in radiology departments. More laboratory
and clinical research is necessary to investigate methods
for reducing radiation exposure during VCUG.
our study suggests that the high validity and excellent
agreement of the photofluorography method in the di-
agnosis and grading of VUR is comparable to that of spot
films and also provides a 50%–90% reduction in radiation,
making it the preferred method.
The authors would like to appreciate Dr hebrani
(radiologist),Dr Esmaili and Dr Ghaneh for their advocat-
No special source of support.
1. lee RS, Diamond DA, Chow JS. Applying the AlARA concept to the
evaluation of vesicoureteric reflux. Pediatr Radiol. 2006;36 (Suppl
Darge K. Diagnosis of vesicoureteral reflux with ultrasonography.
Pediatr Nephrol. 2002;17(1):52-60.
Riccabona M. Cystography in infants and children: a critical ap-
praisal of the many forms with special regard to voiding cystoure-
thrography. Eur Radiol. 2002;12(12):2910-8.
Riccabona M, Fotter R. Urinary tract infection in infants and chil-
dren: an update with special regard to the changing role of reflux.
Eur Radiol. 2004;14 (Suppl 4):l78-88.
Sulieman A, Theodorou K, Vlychou M, Topaltzikis T, Kanavou D,
Fezoulidis I, et al. Radiation dose measurement and risk estima-
tion for paediatric patients undergoing micturating cystoure-
thrography. Br J Radiol. 2007;80(957):731-7.
Ward Vl. Patient dose reduction during voiding cystourethrogra-
phy. Pediatr Radiol. 2006;36 (Suppl 2):168-72.
European radiology and nuclear medicine URCoRatEC. Radiation
Protection 118: Referral guidelines for imaging. [cited]; Available
hernandez RJ, Goodsitt MM. Reduction of radiation dose in pe-
diatric patients using pulsed fluoroscopy. AJR Am J Roentgenol.
lebowitz Rl, olbing h, Parkkulainen KV, Smellie JM, Tamminen-
Mobius TE. International system of radiographic grading of vesi-
coureteric reflux. International Reflux Study in Children. Pediatr
10. Gordis l. Epidemiology. Epidemiology. 2 ed ed. Philadelphia: WB
saunders 2000. p. 63-82.
11. Kleinman PK, Diamond DA, Karellas A, Spevak MR, Nimkin K, Be-
langer P. Tailored low-dose fluoroscopic voiding cystourethrogra-
phy for the reevaluation of vesicoureteral reflux in girls. AJR Am J
Roentgenol. 1994;162(5):1151-4; discussion 5-6.
12. Bazopoulos EV, Prassopoulos PK, Damilakis JE, Raissaki MT, Me-
gremis SD, Gourtsoyiannis NC. A comparison between digital
fluoroscopic hard copies and 105-mm spot films in evaluating
vesicoureteric reflux in children. Pediatr Radiol. 1998;28(3):162-6.
13. Martin CJ, hunter S. Reduction of patient doses from barium meal
and barium enema examinations through changes in equipment
factors. Br J Radiol. 1994;67(804):1196-205.
14. Persliden J, helmrot E, hjort P, Resjo M. Dose and image quality in
the comparison of analogue and digital techniques in paediatric
urology examinations. Eur Radiol. 2004;14(4):638-44.
15. Almen A, Mattsson S. The radiation dose to children from X-
ray examinations of the pelvis and the urinary tract. Br J Radiol.