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Vol. 139, April
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THE JOURNAL OF UROLOGY
Copyright © 1988 by The Williams & Wilkins Co.
STRESS INCONTINENCE: CLASSIFICATION AND SURGICAL
APPROACH
JERRY G. BLAIVAS
AND
CARL A. OLSSON
From the Department of Urology, Columbia University and J. Bentley Squire Urologic Clinic, and The Presbyterian Hospital in the City of
New York, New York, New York
ABSTRACT
We present a modified classification for stress urinary incontinence based on the nature of vesical
neck descent and the integrity of the intrinsic sphinteric mechanism. Surgical treatment was
undertaken in 72 patients with this classification. With a minimum followup of 18 months there
was a 94 per cent cure rate with respect to stress incontinence. However, in 14 patients significant
frequency and urgency developed, which persisted for at least 6 months postoperatively. Of these
patients 13 had undergone a pubovaginal sling procedure, 3 of whom had refractory symptoms,
including urge incontinence, which resulted in augmentation cystoplasty in 2 and supravesical
urinary diversion in 1. (J. Ural., 139: 727-731, 1988)
The precise anatomical and physiological mechanisms involved in the maintenance of urinary continence are poorly
understood. Nevertheless, certain basic observations have withstood the test of time and the pursuits of many investigators.
Since the classical work of Enhorning1 and Hodgkinson,2· 3 it
has been well documented that urinary continence is achieved
because maximum urethral pressure remains greater than intravesical pressure during bladder filling and that increases in
intra-abdominal pressure are transmitted approximately
equally to the bladder and proximal urethra. 4 - 7 It has been
further suggested that, to a large extent, the vesical neck and
proximal urethra are normally "intra-abdominal" structures,
that is they lie above a well supported pelvic diaphragm and
they are positioned in such a way to promote the equal distribution of forces to the bladder and urethra during increases in
intra-abdominal pressure.
It follows then that stress incontinence may occur by 2
mechanisms. In the first and by far the most common condition
the vesical neck and proximal urethra retain their basic sphincteric function. Resting urethral pressure is much greater than
intravesical pressure but during sudden increases in intraabdominal pressure transmission becomes unequal, intravesical
pressure exceeds urethral pressure and leakage occurs. This
unequal transmission of pressure occurs because there is a loss
of support to the vesical neck such that during stress it descends
to a position that is "outside" of the abdominal cavity. In
practical terms this condition may be thought of as a "hernia"
of the vesical neck and operations that are designed to "repair
the hernia" generally are successful, with reported cure rates
in excess of 90 per cent.8 - 17
In the second condition the urethra no longer functions as a
sphincter. Urethral pressure often is low and urinary leakage
occurs with the slightest provocation. In other instances the
urethra has become fibrotic, rigid and deformed, usually from
multiple prior operations. In either case since the incontinence
is not owing to abnormalities of descent, there is no "hernia"
to repair and the usual urethropexy operations have a failure
rate of at least 15 to 20 per cent. 17- 19 On the other hand, surgical
repair with a pubovaginal sling has been effective in 95 to 98
per cent of these patients. 20 • 21 This type of incontinence is
almost always owing to multiple failed operations for stress
incontinence, myelodysplasia or other neurological lesions involving sympathetic outflow. 20 - 23
From these observations it is obvious that a clear understanding of the underlying pathophysiology is of the utmost imporAccepted for publication July 17, 1987.
727
tance for the proper selection of the most appropriate surgical
repair. We present our experience with a modified classification
system and the results of surgical treatment based on that
system.
MATERIALS AND METHODS
We analyzed retrospectively 181 consecutive women with a
clinical and urodynamic diagnosis of stress urinary incontinence seen between January 1983 and July 1985. Each patient
had been referred by a urologist or gynecologist for videourodynamic studies. A detailed history was obtained from each
patient and each was examined in the dorsal lithotomy position
with a full bladder. If incontinence was not demonstrated with
cough or Valsalva's maneuver, the patient was re-examined in
the sitting or standing position. Videourodynamic studies were
performed as described previously. 24 Stress incontinence was
defined as the involuntary loss of urine per urethram that
occurred when, in the absence of a detrusor contraction, intravesical pressure exceeded urethral pressure. 25 Detrusor instability was defined as a sudden, involuntary increase in
detrusor pressure of any magnitude that occurred during bladder filling at a rate consistent with medium fill cystometry.
During cystometry the patient was instructed not to void or try
to suppress micturition but, rather, to report the sensations to
the examiner. It should be noted that this definition of instability differs from that recommended by the International
Continence Society. 26 The patients were classified further according to a scheme that was modified from Green, 26 McGuire
and associates, 11 and Blaivas. 27
Type O (fig. 1). There is a typical history of stress incontinence but no urinary leakage is demonstrated during the clinical and urodynamic investigation. At videourodynamic study
the vesical neck and proximal urethra are closed at rest and
situated at or above the superior margin of the symphysis pubis.
During stress the vesical neck and proximal urethra descend
and open, assuming an anatomical configuration similar to that
seen in types I and II to be described. Failure to demonstrate
incontinence probably is owing to momentary voluntary contraction of the external urethral sphincter during the examination.
Type I (fig. 2). The vesical neck is closed at rest and situated
at or above the inferior margin of the symphysis. During stress
the vesical neck and proximal urethra open and descend less
than 2 cm., and urinary incontinence is apparent during periods
of increased intra-abdominal pressure. There is little or no
cystocele.
728
BLAIVAS AND OLSSON
A
B
FJG. 1. Type O stress incontinence. A, at rest base of bladder is flat and situated above superior margin of symphysis pubis (solid line). B,
during cough there is rotational descent of urethra and bladder base. Vesical neck opens but urinary leakage is not visualized.
A
B
FIG. 2. Type I stress incontinence. A, at rest base of bladder is flat and situated at superior margin of symphysis pubis (solid line). B, during
Valsalva's maneuver bladder base descends approximately 1 cm., vesical neck and urethra open, and leakage occurs.
A
B
FIG. 3. Type IIA stress incontinence. A, during bladder filling base of bladder is flat and situated at level of superior margin of symphysis
pubis. B, during cough there are marked descent and rotation of bladder and urethra well below inferior margin of pubis. Urethra opens widely
and leakage occurs.
Type IIA (fig. 3). The vesical neck is closed at rest and
situated above the inferior margin of the symphysis pubis.
During stress the vesical neck and proximal urethra open and
descend more than 2 cm., and there is an obvious cystourethrocele. Urinary incontinence is apparent during periods of
increased intra-abdominal pressure.
Type JIB (fig. 4). The vesical neck is closed at rest and
situated below the inferior margin of the symphysis pubis.
During stress there may or may not be further descent but the
proximal urethra opens and incontinence ensues.
Type III (fig. 5). The hallmark of type III stress urinary
incontinence is that the vesical neck and proximal urethra are
open at rest in the absence of a detrusor contraction. The
proximal urethra no longer functions as a sphincter. In most
instances there is obvious urinary leakage that may be gravitational in nature or associated with minimal increases in
intravesical pressure. However, if the urethra is fibrotic and
narrowed, incontinence may only be demonstrated with large
increases in intra-abdominal pressure.
The type of anti-incontinence surgery performed was determined according to the following rationale. Initially in this
series either a Marshall-Marchetti-Krantz or Burch procedure
was recommended for patients with types Oto HA incontinence.
However, in the subsequent 2 years a modified Pereyra operation, as described by Raz, 14 was the procedure of choice. The
modified Pereyra operation also was chosen for patients with
type IIB incontinence but in these patients it was considered
particularly important to ensure adequate mobilization of the
vesical neck and proximal urethra, freeing these structures from
their vaginal attachments. Creation of a pubovaginal sling was
the treatment of choice for patients with type III incontinence
unless they had not undergone previous anti-incontinence procedures, in which case an inflatable sphincter prosthesis was
recommended.
RESULTS
The 181 female patients were from 12 to 86 years old, with a
mean age of 55 years. Of the women 58 had undergone a total
729
STRESS INCONTINENCE: CLASSIFICATION AND SURGICAL APPROACH
A
FIG. 4. Type IIB stress incontinence. A, during filling base of bladder is flat but it is situated below level of inferior margin of pubis. B, during
cough there are further descent and opening of urethra with visible leakage.
Type of incontinence compared to symptoms (urinary
frequency, urgency and/or urge incontinence) and prior surgery
TABLE 1.
Symptoms
Reproduced
Total No.
by
Operations/No.
Incontinence
Detrusor
Previous
Pts. Who Had
Type
No. Pts. (%) Instability/ Hysterectomy Undergone Prior
Total No.
Anti-Incontinence
Pts. With
Operations
Symptoms
0
I
II
III
Totals
21
30
92
38
181
(11)
(17)
(51)
(21)
(100)
TABLE
FIG. 5. Type III stress incontinence. During bladder filling base of
bladder is just below superior margin of symphysis pubis. Indentation
on either side of vesical neck is from 2 prior Marshall-MarchettiKrantz operations. Proximal urethra and vesical neck are open despite
intravesical pressure of only 6 cm. water.
of 117 previous anti-incontinence operations and 41 hysterectomies. In 31 patients hysterectomy was performed at the same
time as an anti-incontinence operation and in 11 it was an
isolated procedure.
Over-all, type O incontinence was found in 21 patients (11
per cent), type I in 30 (17 per cent), type II in 92 (51 per cent)
and type III in 38 (21 per cent). Of the patients 96 complained
of urinary frequency, urgency and urge incontinence, 35 of
whom had detrusor instability. Two patients had concomitant
vesicovaginal fistulas and 3 had urethral diverticula. A further
breakdown of these data is presented in table 1.
Urodynamic data are presented in table 2. Over-all, detrusor
instability was seen in 50 women (28 per cent) but in 11 of
them it was asymptomatic. There was no correlation between
the type of incontinence and the presence of instability. Moreover, only 36 per cent of the patients who complained of urinary
frequency, urgency or urge incontinence had demonstrable
detrusor instability. A total of 152 women (84 per cent) were
able to void with a voluntary detrusor contraction during the
videourodynamic evaluation.
Corrective surgery was performed in 72 patients (table 3).
With a minimum followup of 18 months (range 18 months to
4 years), stress incontinence was cured in 68 patients (94 per
cent). Three patients were asymptomatic for 1 to 2 months
after undergoing a modified Pereyra operation for type IIA
stress incontinence but, subsequently, stress incontinence recurred (type III in 2 patients and type IIA in 1). In 1 patient
type II stress incontinence recurred 6 months after a Burch
colposuspension. Of the 4 surgical failures 3 subsequently
2/11
7/14
19/55
7/16
35/96
3
0
6
3/3
36/26
78/29
117 /58
22
11
42
2. Urodynamic data
No. Pts. Who
Voided With
Voluntary
Incontinence Cystometric
Maximum Detrusor
Detrusor
Detrusor
Type (No.
Capacity
Pressure During
Instability Contractions
Voiding (mean)
pts.)
(mean)
During
Videourodynamic
Study
0 (21)
I (30)
II (92)
II (38)
100-600
150-750
100-800
75-750
(365)
(410)
(400)
(350)
7
9
23
11
21
26
75
30
21-90
15-66
12-90
6-39
(37)
(25)
(30)
(24)
underwent a pubovaginal sling procedure and all are now completely continent with a minimum followup of 6 months. However, the second operations are not included in the data from
this study because of the short followup.
In 14 patients clinically significant frequency, urgency and
urge incontinence developed, which persisted for more than 6
months postoperatively. Of these patients 13 had detrusor
instability and only 5 of them had had this condition preoperatively. Thus, there was no correlation between the presence of
preoperative detrusor instability and postoperative symptoms.
Of the 8 patients in whom detrusor instability developed postoperatively 7 had undergone a pubovaginal sling procedure for
type III stress incontinence and 1 had undergone a MarshallMarchetti-Krantz operation for type IIA. All of these patients
had objective videourodynamic documentation of urethral obstruction at the site of surgical repair. Three patients, all of
whom had undergone a pubovaginal sling procedure, failed all
attempts at conservative treatment of instability (manifest as
urge incontinence) and 2 underwent augmentation cystoplasty.
These latter 2 patients are completely continent, although they
require intermittent self-catheterization. The third patient
elected supravesical urinary diversion. The other 11 patients in
this group are no longer incontinent but they void on the
average of every 2 hours during the day. None of these patients
desires further treatment.
730
BLAIVAS AND OLSSON
TABLE
Incontinence
Type
0
I
II
III
Totals
3. Surgical treatment
MarshallMarchettiKrantz or
Burch
Total
No. Pts.
Modified
Pereyra
12
13
27
20
7
7
13
13
72
27
22
4
5
Anteroposterior
Repair
Pubovaginal
Sling
Sphincter
Prosthesis
1
I
1
1
19
1
21
I
* Repair of urethral diverticulum.
t Repair of vesicovaginal fistula.
A woman with type II stress incontinence and asymptomatic
detrusor instability preoperatively suffered frequency, urgency
and urge incontinence postoperatively, although detrusor instability was not demonstrated. Repeat urinalysis and culture were
normal, cystourethroscopy was unremarkable and videourodynamic studies revealed unobstructed micturition.
DISCUSSION
The original impetus for classifying stress urinary incontinence was provided by the observations of Jeffcoate and
Roberts, 28 and Hodgkinson 2 that the anatomical relationship
between the urethra and bladder base was important for the
maintenance of continence. Subsequently, Green described 2
distinct types of stress incontinence: type I was characterized
by loss of the posterior urethrovesical angle and in type II, not
only was this angle lost, but there was posterior, inferior and
rotational descent of the the bladder base and urethra. 26 The
anatomy of type II corresponded to that of a cystourethrocele.
The importance of this classification was obvious; patients with
type I anatomy had an initial cure rate of 90 per cent after
simple vaginal operations (anterior colporrhaphy), whereas the
cure rate in type II was only 50 per cent. 26 • 29- 31 Furthermore,
when a retropubic suspension operation (Marshall-MarchettiKrantz) was performed for type II anatomy the cure rate was
in excess of 90 per cent. Subsequent reports have documented
the efficacy of retropubic suspensions.B-17
McGuire and associates modified Green's original classification to include type III stress incontinence, which was characterized by a proximal urethra that no longer functioned as a
sphincter. 11 •12 Urethral pressure was decreased markedly and
the vesical neck was open at rest. Although the posterior
urethrovesical angle and the urethral inclination were not
assessed, from a clinical standpoint types I and II of McGuire
and associates were identical to those of Green. In their series
the surgical approach was dictated by the type of incontinence.
All 69 patients with type I underwent anterior colporrhaphy.
The over-all cure rate was 86 per cent. Of those 176 patients
with type II incontinence an anterior urethropexy (MarshallMarchetti-Krantz or Burch) was curative in 172 (98 per cent).
Of the 102 patients with type III 98 were continent after
creation of a pubovaginal sling (98 per cent).
Stamey recommended a much simpler approach. 17 He suggested that "surgically curable urinary incontinence in females
should be defined literally as the visual demonstration of a
simultaneous loss of urine with the rise and fall of abdominal
pressure during coughing. Without this demonstration, no patient should be operated upon for stress urinary incontinence."
He further classified the incontinence according to severity.
Grade I was leakage only with severe stress, such as coughing
or laughing, grade 2 was leakage with· walking, running and so
forth, and grade 3 was total urinary incontinence. Using these
criteria he reported a 91 per cent success rate in 203 patients
treated by endoscopic suspension of the vesical neck. 17 Of the
patients 188 had undergone previous anti-incontinence surgery
and 41 had total incontinence. The cure rate in this latter group
was 78 per cent.
We have modified the most recent classification to include
types 0, IIA and IIB. In type O the patient complains of stress
incontinence but it is not objectively demonstrated. Nevertheless, the anatomical substrate for stress incontinence is seen at
fluoroscopy when during stress the vesical neck opens and
descends. According to Stamey's thesis, these patients would
not be candidates for surgical repair. All 12 patients in our
series with type O stress incontinence were cured by surgery
(retropubic suspension in 4, modified Pererya procedure in 7
and anterior repair in 1). Type IIA corresponds to Green's type
2. Type IIB is characterized by a vesical neck and proximal
urethra that are fixed at or below the level of the inferior border
of the symphysis pubis. In our series there were 27 patients
who underwent surgical treatment for types IIA and IIB incontinence and all but 1 were cured of the stress incontinence. In
the patients with type IIB incontinence care was taken to free
the proximal urethra and vesical neck completely from the
vaginal wall so that they could be suspended without tension.
The preoperative recognition of type III stress incontinence
is of the utmost importance because, in our opinion, the usual
urethropexy operations have an unacceptably high failure rate.
The treatment of choice is a pubovaginal sling except for those
few patients who have not had prior surgery. In these latter
cases a sphincter prosthesis theoretically is ideal. Unfortunately, there are only a few published series to support these
contentions. However, some observations have been confirmed.
Type III stress incontinence is seen in approximately 75 per
cent of the patients who have failed 2 or more urethropexy
operations. 20• 23 In several series the failure rate for those conditions most likely to represent type III stress incontinence
(grade 3 according to Stamey's classification) ranged from 15
to 22 per cent. 17' 19 In our previous series20 and that of McGuire
and associates 11 the surgical cure rate of type III stress incontinence treated by a pubovaginal sling was greater than 90 per
cent. Moreover, none of our patients has had recurrent stress
incontinence. Rather, 3 patients had refractory urge incontinence that was cured by augmentation cystoplasty in 2. Four
other patients had persistent problems with urinary frequency,
all of whom had bladder outlet obstruction at the level of the
sling. Thus, it appears that the major disadvantage of the
pubovaginal sling is the propensity to cause urethral obstruction.
Although the sphincter prosthesis theoretically is ideal for
the treatment of type III stress incontinence, in practice the
complication rate after multiple previous operations precludes
this modality of treatment for most patients. In the series of
Light and Scott 39 women with 2.2 prior incontinence operations underwent implantation of a sphincter prosthesis. 32 In 4
patients (10 per cent) the prosthesis was removed because of
infection or erosion and 14 (36 per cent) required 21 additional
operations because of surgical complications. Despite these
multiple operations and revisions, the final failure rate was still
15 per cent with a followup of 3 to 78 months (mean 38 months).
Of further interest is the fact that in none of the reported
series was preoperative detrusor instability a significant risk
factor mitigating against successful surgery, provided that
stress incontinence was demonstrated objectively. Our data are
STRESS INCONTINENCE: CLASSIFICATION AND SURGICAL APPROACH
in complete accord with these findings. In conclusion, we believe that an accurate assessment of the underlying pathophysiology is essential for successful treatment of stress urinary
incontinence and that the presence of detrusor instability and/
or urinary frequency and urgency does not preclude a successful
outcome.
REFERENCES
1. Enhorning, G.: Simultaneous recording of intravesical and intraurethral pressure. A study on urethral closure in normal and
stress incontinent women. Acta Chir. Scand., suppl. 276, p. 1,
1961.
2. Hodgkinson, C. P.: Relationships of the female urethra and bladder
in urinary stress incontinence. Amer. J. Obst. Gynec., 65: 560,
1953.
3. Hodgkinson, G. P.: Direct urethrocystometry. Amer. J. Obst. Gynec., 79: 648, 1960.
4. Constantinou, C. and Govan, D. E.: Contribution and timing of
transmitted and generated pressure components in the female
urethra. In: Female Incontinence. Edited by N. R. Zinner and A.
M. Sterling. New York: Alan R. Liss, pp. 113-120, 1980.
5. Graber, P., Laurant, G. and Tanagho, E. A.: Effect of abdominal
pressure rise on the urethral pressure profile. An experimental
study on dogs. Invest. Urol., 12: 57, 1974.
6. Hilton, P. and Stanton, S. L.: Urethral pressure measurement by
microtransducer: the results in symptom-free women and in
those with genuine stress incontinence. Brit. J. Obst. Gynaec.,
90: 919, 1983.
7. McGuire, E. J. and Herlihy, E.: The influence of urethral position
on urinary continence. Invest. Urol., 15: 205, 1977.
8. Burch, J. C.: Urethrovaginal fixation to Cooper's ligament for
correction of stress incontinence, cystocele and prolapse. Amer.
J. Obst. Gynec., 81: 281, 1961.
9. Burch, J.C.: Cooper's ligament urethrovesical suspension for stress
incontinence. Nine years' experience-results, complications,
techniques. Amer. J. Obst. Gynec., 100: 764, 1968.
10. Cobb, 0. E. and Ragde, H.: Simplified correction of female stress
incontinence. J. Urol., 120: 418, 1978.
11. McGuire, E. J., Lytton, B., Pepe, V. and Kohorn, E. I.: Stress
incontinence. Obst. Gynec., 47: 255, 1976.
12. McGuire, E. J., Lytton, B., Kohorn, E. I. and Pepe, V.: The value
of urodynamic testing in stress urinary incontinence. J. Urol.,
124: 256, 1980.
13. Parnell, J.P., II, Marshall, V. F. and Vaughan, E. D., Jr.: Primary
management of urinary stress incontinence by the MarshallMarchetti-Krantz vesicourethropexy. J. Urol., 127: 679, 1982.
14. Raz, S.: Modified bladder neck suspension for female stress incontinence. Urology, 17: 82, 1981.
15. Stamey, T. A.: Endoscopic suspension of the vesical neck for
731
urinary incontinence. Surg., Gynec. & Obst., 136: 547, 1973.
16. Stamey, T. A., Schaeffer, A. J. and Condy, M.: Clinical and roentgenographic evaluation of endoscopic suspension of the vesical
neck for urinary incontinence. Surg., Gynec. & Obst., 140: 355,
1975.
17. Stamey, T. A.: Endoscopic suspension of the vesical neck for
urinary incontinence in females: report on 203 consecutive patients. Ann. Surg., 192: 465, 1980.
18. Marshall, V. F. and Segaul, R. M.: Experience with suprapubic
vesicourethral suspension after previous failure to correct stress
incontinence in women. J. Urol., 100: 647, 1968.
19. Parnell, J. P., III, Marshall, V. F. and Vaughan, E. D., Jr.: Management of recurrent urinary stress incontinence by the
Marshall-Marchetti-Krantz vesicourethropexy. J. Urol., 132:
912, 1984.
20. Blaivas, J. G. and Salinas, J.: Type III stress urinary incontinence:
importance of proper diagnosis and treatment. Surg. Forum, 35:
473, 1984.
21. McGuire, E. J. and Lytton, B.: Pubovaginal sling procedure for
stress incontinence. J. Urol., 119: 82, 1978.
22. Barbalias, G. A. and Blaivas, J. G.: Neurologic implications of the
pathologically open bladder neck. J. Urol., 129: 780, 1983.
23. McGuire, E.: Urodynamic findings in patients after failure of stress
incontinence operations. In: Female Incontinence. Edited by N.
R. Zinner and A. M. Sterling. New York: Alan R. Liss, pp. 351360, 1980.
24. Blaivas, J.: Multichannel urodynamic studies. Urology, 23: 421,
1984.
25. Bates, P., Bradley, W. E., Glen, E., Griffiths, D., Melchoir, H.,
Rowan, D., Sterling, A., Zinner, N. and Hald, T.: The standardization of terminology of lower urinary tract function. J. Urol.,
121: 551, 1979.
26. Green, T. H., Jr.: The problem of urinary stress incontinence in
the female: an appraisal of its current status. Obst. Gynec.
Survey, 23: 603, 1968.
27. Blaivas, J. G.: Classification of stress urinary incontinence. Neurourol. Urodynam., 2: 103, 1984.
28. Jeffcoate, T. N. A. and Roberts, H.: Observations on stress incontinence of urine. Amer. J. Obst. Gynec., 64: 721, 1952.
29. Green, T. H., Jr.: Development of a plan for the diagnosis and
treatment of urinary stress incontinence. Amer. J. Obst. Gynec.,
83: 632, 1962.
30. Bailey, K. V.: A clinical investigation into uterine prolapse with
stress incontinence: treatment by modified Manchester colporrhaphy. J. Obst. Gynaec. Brit. Emp., 69: 291, 1954.
31. Low, J. A.: Management of anatomic urinary incontinence by
vaginal repair. Amer. J. Obst. Gynec., 97: 308, 1967.
32. Light, J. K. and Scott, F. B.: Management of urinary incontinence
in women with the artificial urinary sphincter. J. Urol., 134:
476, 1985.
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