British Journal of Urology (1975), 47, 567-570 0
Measurement of the Volume of Residual Urine using 13%Hippuranand the Gamma Camera E . KALIS, M. LIKOURINAS,F. DERMENTZOGLOU, B. SAMARA and N. GOULANDR~S
Department of Urology, University of Athens, King Paul’s Hospital, Athens, Greece
The volume of residual urine in the bladder is an important factor which often needs to be determined in order to complete a diagnosis in patients with obstructive uropathy. Many methods have been described and although they provide reliable measurements of this volume most are invasive techniques. Thus, the post-micturition catheterisation of the bladder is a simple and accurate method, but may cause trauma or infection which is undesirable, particularly in patients with renal failure. Furthermore, passing a catheter into the bladder may be prevented by a urethral stricture so that in these cases direct measurement of the residual urine is not possible (Cotran and Kass, 1958; Beer, 1936). The volume of residual urine can also be estimated by intravenous urography and the postmicturition cystogram is widely used to show the completeness of micturition. However, good renal function is required and the measurement of residual urine is unreliable by this method in patients with renal failure. The phenolsulfonphthalein test (Smith, 1960) gives an accurate measurement of the volume of residual urine provided that renal function is not impaired. In 1961, Mulrow, Huvos and Buchanan described a new method of determining the volume of residual urine using Diodrast labelled with Iodine-131. Diodrast is rapidly excreted into the urine and the measurements of radioactivity are not difficult. The radioactive substance is injected intravenously in a dose of 10 to 20 pCi, mixed with 1 ml of unlabelled 35% Diodrast solution. Radioactivity measurements over the bladder before and after micturition are made 1 to 3 hours later, depending on the blood urea level. The difference in radioactivity before and after micturition, divided by the volume of voided urine, gives the radioactivity in each millilitre of urine. The post-micturition radioactivity over the bladder, divided by the radioactivity of each millilitre of voided urine, gives the volume of residual urine. A disadvantage of the method is that it cannot be applied to patients with hypersensitivity to Diodrast. In 1964, Lindbjerg and Brandt applied a method based on the principle of Mulrow et al. (1961) using Hippuran labelled with 1 3 1 1 . In that method a collimator was placed 25 to 30 cm from the abdominal wall before and after micturition to avoid any false measurement of radioactivity in the bladder. A difference of 1 cm in the distance from the bladder to scintillation crystal could lead to an error of up to 6%. An additional error could occur in the presence of a full bladder because of the small field of view of the collimator. The purpose of this work was to minimise any false measurement likely to occur from the above-mentioned factors. Instead of a collimator, we have used the y-camera and placed it in contact with the abdominal wall before and after micturition in order to obtain a more accurate measurement of the radioactivity over the bladder. Furthermore, the field of view of the ycamera is large, so that it should be possible to measure the radioactivity over a full bladder.
Method The following method was employed, based on the calculation described by Lindbjerg and Brandt (1964). 15 pCi of 1311-Hippuranwere injected intravenously and the patient was instructed to avoid micturition for 1 hour. Within the first 15 minutes after the injection, a renogram (using 567
568
3211
BRITISH JOURNAL OF UROLOGY
-
-
t. 2 8 0 -
2
240-
--
-
/
/'
standard equipment) was obtained to give an indication of renal function. 1 hour after the injection the y-camera was lowered on to the abdominal wall and the radioactivity over the bladder was measured (Cpre): a second measurement was made over the same area after micturition (Cpost) and the volume of urine was also measured (Vu). The radioactivity over the precordium (Bkg) was recorded and the volume of residual urine was then calculated from the following equation:
Patients
The method was applied to 26 unselected patients from the Urological Department. 20 were male and 6 female, the age range being 33 to 79 years. The blood urea was determined before the test. The control value was obtained by catheterisation of the bladder 5 minutes after the postmicturition measurement of radioactivity. Results
The clinical details of the patients and the values for residual urine obtained by the ?-camera and by catheterisation are presented in Table I. The comparison between these values IS shown in Figure 1 ; the correlation is highly significant. Discussion
Our experience with this method has shown it to be both simple and reliable. N o preparation of the patient is required and apart from the initial injection, it is non-invasive and does not disturb the patient. The only significant disadvantage is the requirement to postpone micturition for 1 hour and 1 patient in this study with severe frequency was excluded for this reason. In contrast to other methods used to measure residual urine, this method can be applied with moderately impaired renal function. It is also a convenient method for use in those patients who are unable to micturate either due to retention of urine or to psychological factors.
569
MEASUREMENT OF THE VOLUME OF RESIDUAL URINE
Table I Comparison of the Results of Determination of the Volume of Residual Urine with 1311-Hippuran and Catheterization of the Bladder. Case No.
Sex
~
1
2 3 4 5
6 7 8 9 10 11 12 13 14 15
16 17 18 19 20
*
Age _
M
Blood Urea mg%
Residual Urine (ml) A
I
>
Diagnosis
Gamma Camera
Catheter
Prostatic hypertrophy+ bladder stone Prostatic hypertrophy Urinary infection Bladder-neck obstruction Renal dysplasia Renal dysplasia Urethral diverticulum Nephrolithiasis Prostatic hypertrophy Prostatic hypertrophy Prostatic hypertrophy Bladder-neck obstruction Bladder turnour Neurogenic bladder Bladder turnour Bladder turnour Bladder turnour Prostatic hypertrophy Prostatic hypertrophy Bladder stone+ prostatic hypertrophy Postoperative bladderneck obstruction Chronic pyelonephritis Nephrolithiasis Prostatic hypertrophy Prostatic hypertrophy Bladder turnour
88
85
4 4.8 44.8 0 5.9 0 2 19.7
4 3 40 0 0 0 0 18 80
_
79
75
M 65 42 M M 4 4 33 M 40 F 49 F 38 M 57 M M 73 62 M 43 M M 67 F 17 M 59 F 62 55 F 69 M M 60 M 75
45 75 40 30 38 40 65 45 50
45 50 45 35 50
45 40 45 50
45
21
M
72
45
22 23 24 25 26
M F M M M
60 18 68 62
50
64
35 45 50 40
*
6.5 269 6.3
5
21 10.5 28.7 180 0 210
270 6 300 27 10 20 180 0 210
120
120
40 0
50
*
*
94 0
0 150 91 0
These patients were unable to pass urine spontaneously.
The use of the gamma camera in the measurement of residual urine has simplified the method and increased the accuracy. The availability of the gamma camera and radio-isotope facilities will continue to limit these methods to larger centres. However, it is not suggested that this method is essential for routine clinical work but it is recommended that it is ideal for selected patients and for clinical research, where a measurement of residual urine is required.
Summary A modification of the method of determining the volume of residual urine in the bladder using
1311-Hippuranand the gamma camera is described. The method was applied to 26 patients with either normal or impaired renal function and proved to be both reliable and accurate.
References BEER,E. (1936). Visualization of the amount of residual urine. Journal of the American Medical Association, 107, 1886. 47/54
570
BRITISH JOURNAL OF UROLOGY
COTRAN, R. S. and KASS,E. H. (1958). Determination of the volume of residual urine in the bladder without catheterization. New England Journal of Medicine, 259, 337-339. LINDBJERG. I. F. and BRANDT,N. J. (1964). Indirect determination of the volume of residual urine with 1317labelled Hippuran. Actu chirurgicu Scandinavica, 127, 675-680. MULROW, P. J., Huvos, A. and BUCHANAN, D. L.(1961). Measurement of residual urine with 1131-labelled Diodrast. Journal of Laboratory and Clinical Medicine, 57, 109-113. SMITH,D. R. (1960). Estimation of the amount of residual urine by means of the phenolsulfonphthalein test. Journal of Urology, 83, 188-191.
The Authors E. Kalis, MD., Senior Registrar. M. Likourinas, MD.. Assistant. F. Dermentzoglou, Physicist, Radioisotope Department, S t Sabbas’s Hospital. B. Samara, Consultant, Radioisotope Department, St Sabbas’s Hospital. N. Goulandris, M.D, Assistant. Requests for reprints should be addressed to Dr E. Kalis, Department of Urology, University of Athens, King Paul’s Hospital. Athens, Greece.
Measurement of the Volume of Residual Urine using 13%Hippuranand the Gamma Camera E . KALIS, M. LIKOURINAS,F. DERMENTZOGLOU, B. SAMARA and N. GOULANDR~S
Department of Urology, University of Athens, King Paul’s Hospital, Athens, Greece
The volume of residual urine in the bladder is an important factor which often needs to be determined in order to complete a diagnosis in patients with obstructive uropathy. Many methods have been described and although they provide reliable measurements of this volume most are invasive techniques. Thus, the post-micturition catheterisation of the bladder is a simple and accurate method, but may cause trauma or infection which is undesirable, particularly in patients with renal failure. Furthermore, passing a catheter into the bladder may be prevented by a urethral stricture so that in these cases direct measurement of the residual urine is not possible (Cotran and Kass, 1958; Beer, 1936). The volume of residual urine can also be estimated by intravenous urography and the postmicturition cystogram is widely used to show the completeness of micturition. However, good renal function is required and the measurement of residual urine is unreliable by this method in patients with renal failure. The phenolsulfonphthalein test (Smith, 1960) gives an accurate measurement of the volume of residual urine provided that renal function is not impaired. In 1961, Mulrow, Huvos and Buchanan described a new method of determining the volume of residual urine using Diodrast labelled with Iodine-131. Diodrast is rapidly excreted into the urine and the measurements of radioactivity are not difficult. The radioactive substance is injected intravenously in a dose of 10 to 20 pCi, mixed with 1 ml of unlabelled 35% Diodrast solution. Radioactivity measurements over the bladder before and after micturition are made 1 to 3 hours later, depending on the blood urea level. The difference in radioactivity before and after micturition, divided by the volume of voided urine, gives the radioactivity in each millilitre of urine. The post-micturition radioactivity over the bladder, divided by the radioactivity of each millilitre of voided urine, gives the volume of residual urine. A disadvantage of the method is that it cannot be applied to patients with hypersensitivity to Diodrast. In 1964, Lindbjerg and Brandt applied a method based on the principle of Mulrow et al. (1961) using Hippuran labelled with 1 3 1 1 . In that method a collimator was placed 25 to 30 cm from the abdominal wall before and after micturition to avoid any false measurement of radioactivity in the bladder. A difference of 1 cm in the distance from the bladder to scintillation crystal could lead to an error of up to 6%. An additional error could occur in the presence of a full bladder because of the small field of view of the collimator. The purpose of this work was to minimise any false measurement likely to occur from the above-mentioned factors. Instead of a collimator, we have used the y-camera and placed it in contact with the abdominal wall before and after micturition in order to obtain a more accurate measurement of the radioactivity over the bladder. Furthermore, the field of view of the ycamera is large, so that it should be possible to measure the radioactivity over a full bladder.
Method The following method was employed, based on the calculation described by Lindbjerg and Brandt (1964). 15 pCi of 1311-Hippuranwere injected intravenously and the patient was instructed to avoid micturition for 1 hour. Within the first 15 minutes after the injection, a renogram (using 567
568
3211
BRITISH JOURNAL OF UROLOGY
-
-
t. 2 8 0 -
2
240-
--
-
/
/'
standard equipment) was obtained to give an indication of renal function. 1 hour after the injection the y-camera was lowered on to the abdominal wall and the radioactivity over the bladder was measured (Cpre): a second measurement was made over the same area after micturition (Cpost) and the volume of urine was also measured (Vu). The radioactivity over the precordium (Bkg) was recorded and the volume of residual urine was then calculated from the following equation:
Patients
The method was applied to 26 unselected patients from the Urological Department. 20 were male and 6 female, the age range being 33 to 79 years. The blood urea was determined before the test. The control value was obtained by catheterisation of the bladder 5 minutes after the postmicturition measurement of radioactivity. Results
The clinical details of the patients and the values for residual urine obtained by the ?-camera and by catheterisation are presented in Table I. The comparison between these values IS shown in Figure 1 ; the correlation is highly significant. Discussion
Our experience with this method has shown it to be both simple and reliable. N o preparation of the patient is required and apart from the initial injection, it is non-invasive and does not disturb the patient. The only significant disadvantage is the requirement to postpone micturition for 1 hour and 1 patient in this study with severe frequency was excluded for this reason. In contrast to other methods used to measure residual urine, this method can be applied with moderately impaired renal function. It is also a convenient method for use in those patients who are unable to micturate either due to retention of urine or to psychological factors.
569
MEASUREMENT OF THE VOLUME OF RESIDUAL URINE
Table I Comparison of the Results of Determination of the Volume of Residual Urine with 1311-Hippuran and Catheterization of the Bladder. Case No.
Sex
~
1
2 3 4 5
6 7 8 9 10 11 12 13 14 15
16 17 18 19 20
*
Age _
M
Blood Urea mg%
Residual Urine (ml) A
I
>
Diagnosis
Gamma Camera
Catheter
Prostatic hypertrophy+ bladder stone Prostatic hypertrophy Urinary infection Bladder-neck obstruction Renal dysplasia Renal dysplasia Urethral diverticulum Nephrolithiasis Prostatic hypertrophy Prostatic hypertrophy Prostatic hypertrophy Bladder-neck obstruction Bladder turnour Neurogenic bladder Bladder turnour Bladder turnour Bladder turnour Prostatic hypertrophy Prostatic hypertrophy Bladder stone+ prostatic hypertrophy Postoperative bladderneck obstruction Chronic pyelonephritis Nephrolithiasis Prostatic hypertrophy Prostatic hypertrophy Bladder turnour
88
85
4 4.8 44.8 0 5.9 0 2 19.7
4 3 40 0 0 0 0 18 80
_
79
75
M 65 42 M M 4 4 33 M 40 F 49 F 38 M 57 M M 73 62 M 43 M M 67 F 17 M 59 F 62 55 F 69 M M 60 M 75
45 75 40 30 38 40 65 45 50
45 50 45 35 50
45 40 45 50
45
21
M
72
45
22 23 24 25 26
M F M M M
60 18 68 62
50
64
35 45 50 40
*
6.5 269 6.3
5
21 10.5 28.7 180 0 210
270 6 300 27 10 20 180 0 210
120
120
40 0
50
*
*
94 0
0 150 91 0
These patients were unable to pass urine spontaneously.
The use of the gamma camera in the measurement of residual urine has simplified the method and increased the accuracy. The availability of the gamma camera and radio-isotope facilities will continue to limit these methods to larger centres. However, it is not suggested that this method is essential for routine clinical work but it is recommended that it is ideal for selected patients and for clinical research, where a measurement of residual urine is required.
Summary A modification of the method of determining the volume of residual urine in the bladder using
1311-Hippuranand the gamma camera is described. The method was applied to 26 patients with either normal or impaired renal function and proved to be both reliable and accurate.
References BEER,E. (1936). Visualization of the amount of residual urine. Journal of the American Medical Association, 107, 1886. 47/54
570
BRITISH JOURNAL OF UROLOGY
COTRAN, R. S. and KASS,E. H. (1958). Determination of the volume of residual urine in the bladder without catheterization. New England Journal of Medicine, 259, 337-339. LINDBJERG. I. F. and BRANDT,N. J. (1964). Indirect determination of the volume of residual urine with 1317labelled Hippuran. Actu chirurgicu Scandinavica, 127, 675-680. MULROW, P. J., Huvos, A. and BUCHANAN, D. L.(1961). Measurement of residual urine with 1131-labelled Diodrast. Journal of Laboratory and Clinical Medicine, 57, 109-113. SMITH,D. R. (1960). Estimation of the amount of residual urine by means of the phenolsulfonphthalein test. Journal of Urology, 83, 188-191.
The Authors E. Kalis, MD., Senior Registrar. M. Likourinas, MD.. Assistant. F. Dermentzoglou, Physicist, Radioisotope Department, S t Sabbas’s Hospital. B. Samara, Consultant, Radioisotope Department, St Sabbas’s Hospital. N. Goulandris, M.D, Assistant. Requests for reprints should be addressed to Dr E. Kalis, Department of Urology, University of Athens, King Paul’s Hospital. Athens, Greece.
