Stress urinary incontinence
Michał Szymański, MD
Genesis of the disease
Stress urinary incontinence (SUI) is a civilization disease, which, given the nature of the problem, is an embarrassing and very often hidden ailment. The dysfunction associated with the described problem affects the psychophysical condition of patients dealing with this ailment. Stress urinary incontinence, as well as light and heavy incontinence forcing patients to use incontinence products such as urological liners or incontinence pull up’s pants for adults. This type of prevention does not give full comfort, discretion, and most importantly – a sense of security. However, this condition can be treated not only pharmacologically, but also surgically with the use of minimally invasive surgical techniques – through implantation of urological tapes treating this ailment permanently and giving comfort and safety.
The cause of this disease is a not properly functioning urethral closure mechanism resulting from the weakening of the sphincter muscle of the urethra or the hyperactivity of the bladder, urethra, genitourinary fistulas, dilatation of the bladder. The reasons for this dysfunction include, in case of women, inter alia multiple deliveries, damages of the urinary tract, problems with hormonal system, innate defects. For men, the causes of this condition include urethra surgeries.
The scale of the problem in the world
The incidence of urinary incontinence (UI) was estimated on the basis of 35 independent studies on a group of 230 000 people, belonging to different social groups and five ethnic groups. UI incidence in women was 27.6%, a maximum occurred in the 5th decade of life – 33%. Statistical data from departments and gynaecological and urological outpatient clinics shows that this symptom occurs in approximately 25-30% of patients over 45 years of age. It should be noted that a number of patients never report to the doctor. Every year the U.S. spends on the treatment of UI about 17.5 billion dollars (1995). It is estimated that if everyone in the U.S. who suffer from incontinence would look for help, the cost of the treatment and care would amount to $ 41 billion. Urinary incontinence hampers the normal functioning in the society and is the cause of lower self-esteem and overall well-being. The conducted studies on the population of Norwegian women showed that 46% of them identified the discomfort associated with incontinence as tedious, and 34% – as extremely annoying. The problem of urinary incontinence also has its economic aspect. It has been shown that the costs associated with having to buy the necessary medicines and personal care products exceed for about 64% the standard expenses of healthy women. It is estimated that women with stress urinary incontinence in 1998 spent for the direct aids $ 5642 USD, and the indirect measures 4208 $ U.S. These included the purchase of inserts and hygiene products, costs for professional medical help and expenses for surgical treatment. In England the budget allocated for the treatment of urinary incontinence in women is 2% of the total expenses. In the period from 2000 to 2001 there were 8000 surgical procedures because of urinary incontinence for the amount of 10.3 million pounds from the NHS funds. It has been estimated in the United States that the annual direct medical expenses of urinary incontinence are comparable and similar to those that apply to such diseases as breast cancer, osteoporosis and arthritis.
The needs of Polish market
It has been estimated that in Poland there are 20.000-30.000 procedures of urological tape implantation. However, the real need is much higher. It is assumed that approximately 30% of women suffer from this ailment, which makes about 3 million patients in Poland who should have an urological tape implanted. The percentage data concern also the global market. The tapes offered on the Polish market are available only with reusable applicators. Only a few manufacturers offer the tapes with disposable applicators made of artificial materials. The analysis of the costs associated with the purchase of tapes with applicators and comparing them to the prices of the implant can be concluded that it is more economical to purchase a product with reusable applicators. Each hospital has its own sterilisation centre and can sterilise the reusable applicator on its own, thereby reducing the cost of purchasing a disposable one. The number of sold reusable applicators represents about 1% of the amount sold tapes.
Methods of treatment
Surgical treatment is mainly used in the following cases: stress urinary incontinence, mixed form of urinary incontinence. The methods most frequently used in the surgical treatment of urinary incontinence are:
- suspension of the urethra using the tension free tape through the vagina (e.g. Tension-free Vaginal Tape (TVT), Trans Obturator Tape (TOT));
- extraperitoneal vaginal suspension (Burch colposuspension method, operations by Marshall-Marchetti-Krantz method);
- needle procedures;
- urethral injections (usually with Teflon or collagen);
- loop operations (almost entirely supplanted by TVT and TOT);
- implantation of an artificial sphincter (the highest degree of difficulty, a very rarely used treatment).
Selecting the optimal treatment method is often very difficult and depends on many factors, including: the patient’s body weight, the patient’s age, number of births and the complications associated with them, poor general health, the desire to have children, coexisting chronic diseases, doing competitive sports, experience of the operator.
The effectiveness of the chosen treatment method also depends heavily on the well performed diagnostics, which allows to determine the cause of urinary incontinence and the presence of any accompanying genital pathology.
Characteristics of TOT and TVT implantation methods
In the two treatments (TOT and TVT) the implanted product is a tape made of synthetic polymers (such as polypropylene), or of allogeneic material. Leading manufacturers of synthetic tapes are Ethicon, AMS. These tapes can also be partially resorbable e.g. the T-Sling by Polhernia company.
The set for stress urinary incontinence consisting of a urological tape and a system of applicators for TVT and TOT methods is the subject of the description of implantation methods.
In the surgical treatment of urinary incontinence in women the TVT method (Tension-free Vaginal Tape) and the TOT (Trans Obturator Tape) method is most often used – the Dallop® NM tape is intended for both of them.
This TVT method of surgical treatment of stress urinary incontinence in women enjoys great popularity among surgeons. This procedure is performed under local anaesthesia. It takes about 20 minutes. During this procedure, the tape is introduced through the retro-pubic space, and the ends are drawn up on the abdominal fascia. This is done using special applicators designed for the specificity of the procedure. The applicators allow you to place the tape under the urethra in a safe way, providing high efficiency of the procedure, estimated at about 85% in the long-term evaluation.
The TVT method is a procedure used in the treatment of stress urinary incontinence in women performed with vaginal access, aimed at suspending the middle and posterior part of the urethra.
The second method used more and more commonly in the surgical treatment of urinary incontinence in women is the TOT method. It is a modification of the TVT method limiting the risk associated with it. It primarily reduces the risk of puncturing the bladder or damaging the pelvic or major blood vessels. This treatment is also performed under local anaesthesia, and the duration is shorter. The big difference is the way through which the tape is implanted. For the TOT method special applicators were designed to enable taking the tape through a small space in the foramen obturatum, which reduces the risk of penetrating the bladder and allows the location of the band in a more precise and safe. This provides a method for increasing the efficiency of approximately 95%.
The method TOT uses the access through the foramen obturatum, through which the urological tape is pushed. It aims to create a kind of hammock supporting the urethra in the middle and back part.
Optimal materials /raw materials for urological tapes
Many authors of publications describing the use of various types of urological tapes, assessing the effectiveness of implanting tapes made of material of both human and animal, and synthetic origin said that the use of the tapes made of materials of human and zoonotic origin carries a high risk of complications. The most common are: erosion, infections, absorption of the tape and reduction of the initial parameters of the tapes. In addition, it is difficult to assess the effectiveness of the treatments with their use. However, the use of polypropylene tapes is free from most of these complications. Besides, the polypropylene tapes are characterised by a relatively small loss in the value of the initial parameters, what considerably affects the efficiency of procedures performed.
A randomised study on two groups of New Zealand rabbits to evaluate the response of the bladder tissue in contact with synthetic implants (the TVT tape) and zoonotic implants (SIS – Small Intestinal Submucosal – transplant of porcine origin). The third group was a control group which was subjected to a similar procedure as the other groups, with the difference that it did not have any implant. Observations were carried out for two periods of implantation – 6 and 12 weeks. As a result of these studies it was found that the wall of the bladder in contact with polypropylene showed no inflammatory reaction. Only in 3 of 12 animals the presence of fibrosis was observed. In the test group treated with porcine SIS implant in one animal a strong inflammatory response was observed, in two animals fibrosis was found. In the control group, as expected, there were no changes in the tissues of the bladder. On the basis of these observations, the authors evaluated the conclusion that both materials – both the polypropylene and the porcine SIS implant appears to be safe in contact with the tissues of the bladder. In addition, the polypropylene implant retained its morphological characteristics in the two periods of observation.
Many doctors evaluated the mechanical properties of TVT polypropylene tapes and tapes of human origin (CFL) after their implantation. These studies were carried out on rats, by selecting two observation periods 6 and 12 weeks, because in patients undergoing surgery with the use of tapes the acute tissue reaction to the presence of foreign materials usually occurs in the first three months. Two parameters of the tapes were tested: average breaking load and maximum load at break. The authors assessed that the TVT tapes retain their morphological and strength characteristics after the assessed implantation periods. However, the tapes of human origin (CFL) definitely lose their strength. Both the evaluated parameters, both after 6 and 12 weeks of observation, for the TVT tapes were almost three times higher than for the tapes of human origin (CFL). The doctors in their summary stated that such a significant decrease in the strength parameters can be the cause of low efficiency of the procedures with the application of the tissues of human origin (CFL).
Characteristics of Dallop® NM tape
Urological tape Dallop® NM meets the essential requirements of Directive 93/42/EEC for products classified as Class IIb medical devices. According to the above-mentioned Directive, Annex 9, Rule 8 „All implantable devices and invasive surgical devices for long-term use are in the Class IIb.”
Dallop® NM urological tapes are made of:
- monofilament polypropylene yarn with a thickness of 0.16 mm (185 dtex) – used to produce the main part of the tape;
- polypropylene yarn with a thickness of 0.3 mm (640 dtex) – used to make the handles allowing to fix the tape on an applicator.
Both materials are made of 100% polypropylene homopolymer and are coated with preparations in an amount of not more than 0.25%. Both yarns have a minimised elongation factor (up to 0.5% in water at 40°C ± 2°C) and the corresponding tensile strength. Drains protecting the areas where the tape and the handles are connected are made of medical PVC granulate and are used to protect the tape and the tape handles against pulling out when the tape is put through anatomical structures.
Parameters of Dallop® NM tapes:
|1.||Breaking strength||min. 16 N||117 N|
|2.||Pore size||min. 75 µm||0.38 mm2|
|3||Width||1.0 – 1.2 cm||1.1 cm|
The Dallop® NM tapes have smooth edges and do not require additional protection, because the implant does not cause the risk of tissue damage.
The Dallop® NM tape is packaged in double medical packaging – BOM paper-film reel with a gusset suitable for ethylene oxide (EO) sterilisation. A medical device after packaging undergoes sterilisation with ethylene oxide (EO) in accordance with the requirements of EN ISO 11135-1.
The Dallop® NM tape is available in 2 sizes with a length of 60cm and 45cm, the handles are blue and made of polypropylene yarn, and the covers (drains) are made of heat-shrinkable material.
Application of the tape
The Dallop® NM tape is designed for use in the surgical treatment of female urinary incontinence by means of TVT and TOT methods. These methods are used to treat stress or a mixed form of urinary incontinence. The tape is intended to replace weakened pelvic floor muscles, which are not able to provide an appropriate angle of the urethra, leading to urinary incontinence. Creating a support under the urethra the tape restores it to its natural position.
The provide safe implantation of the Dallop® NM tape appropriate applicators were designed: a modified TVT needle, a modified Emmet needle and curved Emmet needles (left and right). Modifications to all the applicators included adapting their ends to the fixing handles of the tapes so that you can attach the tape holder on the applicator to securely introduce the tape.
The raw material used to manufacture the applicators is stainless steel of composition appropriate for the production of medical instruments. The applicators are packed in double polythene film and a cardboard box.
The Dallop® NM tape is sold separately or in a set with applicators for a TVT and / or TOT method.
Research on the Dallop® NM urological tape – produced by Tricomed S.A. and placed on the market after obtaining the CE mark and the certificate of registration was carried out in Matopat Specialist Hospital in Toruń during 01.09.2010 – 01.09.2011. Three medical obstetrics and gynaecology specialists took part in the study: Janusz Stankiewicz MD, PhD., Michał Szymanski MD, PhD, Piotr Wojtynek MD, PhD. Each of the physicians choosing patients for the clinical trial was both the operator and the person collecting clinical data from the intra- and postoperative period. The aim of this study was to evaluate the efficacy and safety of the Dallop® NM urological tape in the surgical treatment of stress urinary incontinence in women. The study included an risk assessment of complications after the implantation of the tapes and their subsequent impact on the quality of life of the patients.
Materials and methods
20 patients (women) with diagnosed with stress urinary incontinence or a mixed type of this disorder with a predominantly stress component took part in the assessment. Each patient had one Dallop® NM tape implanted; the surgical procedures were performed in the period 13.09.2010 – 08.03.2011. Characteristics of the study group: 4 patients before surgery additionally had urinary urgency. Patients’ age 35 – 74 years, (average age 52 years), BMI between 19 – 41 (average 27). All patients in the preoperative period and during the qualification for the surgery had their medical history collected, and an gynaecological examination with ultrasound performed. In all the patients the test result was positive. Before the surgery urine cultures were performed in order to exclude an urinary tract infection, the urodynamic test confirmed the presence of stress urinary incontinence.
The results took into account the data collected during the operation, after 30 minutes from the surgery, at discharge from the hospital, and within a period of one, three and six months after the surgery. All tapes were implanted with access through the foramen obturatum (TOT), this access is now preferred in most centres dealing with the surgical treatment of stress urinary incontinence as giving fewer complications, shortening the treatment time and eliminating the need for intraoperative cystoscopy compared with the vaginal access (TVT).
Description of the surgical technique: After preparing the operating field a longitudinal incision in the vagina was performed, the vaginal wall was dissected of the urethral, tunnels were created to the sides towards the obturator foramens. Through incisions in the groin folds on both sides an Emmet needle was introduced directing it through the obturator foramens to the previously prepared tunnels. The handles of the Dallop® NM tape connected to the ends of the tape were rove through the hole in the needle and the ends of the tape were led „from the inside out” by withdrawing the needle. The tape was laid without tension under the urethra, then the vaginal wall was sewed. A vaginal compression tampon was applied for a day, after the surgery the catheter was removed from the bladder, the patients urinated on their own. Eighteen operations were carried out under general anaesthesia, in two cases under regional anaesthesia – the type of anaesthesia was chosen by the anaesthesiologist in consultation with his patient.
Results of the studies
The total time of the operation: the 18 TOT operations took 10 – 30 minutes (average 19 minutes). Two operations connected with additional operating procedures (removal of the uterus, vagina wall carvings) lasted 60 minutes; the average for all the 20 patients: 23 min. Assessment of the convenience of using a tape during a surgery (0-5), (0 – cumbersome and difficult to use, 1 – very complicated application, 2 – complicated application, 3 – high degree of difficulty, 4 – small degree of difficulty, 5 – handy and easy application). In two cases the operators rated the tape at 4, in the other cases – 5 (average 4.9). After 30 minutes of surgery the pain strength according to VAS was in the range of 2 – 4, on average 2.3. The type and duration of used painkillers: all the patients were given Ketonal intravenously at a dose of 1 amp. every 8 hours, 9 patients additionally were given Morphine 1 amp. every 6 hours, 5 were given Tramal intravenously 1 amp. Noticeable discomfort on a scale 0-5 (0 – pain, I want to remove the tape, 1 – huge discomfort, 2 – big discomfort, 3 – moderate discomfort, 4 – slight discomfort; 5 – no discomfort) ranged from 4 – 5, average of 4.4. Postoperative complications such as hematoma, urinary retention, need to remove the tape, the temperature above 37.5°C, there were no signs of infection in any of the patients. Hospitalisation time took 1 – 3 days (average 1.95). At discharge from the hospital, the cough stress test result for all the patients was negative, the patients did not report any episodes of urinary incontinence. The pain strength according to VAS was 0 to 2, on average 0.6. Noticeable discomfort in the scale of 0-5 – three patients reported mild discomfort, others no discomfort (4.85 average). Postoperative complications were not observed in any of the cases. One of the patients at discharge reported occurrence of urinary urgency „de novo”. All patients reported to a control check after a month from the surgery. None of them reported any incidents of stress urinary incontinence.
Two patients with the mixed form of urinary incontinence reported the continuing urinary urgency of a similar intensity as in the preoperative period, the treatment with anticholinergics was continued. Pelvic examination: in all patients the post-operative wound healing process was correct, there was no erosion, no hematoma, no need to remove the tape, etc.. Test cough test was negative – 100% of the respondents. The pain strength according to VAS: one patient assessed as „1″, the others as „0″. Noticeable discomfort (scale 0-5) – one of the patients evaluated at „2″, one at „4″, the others at „5″, the average 4.8. 3 months after the surgery in any patient in the entire study group there was no incontinence observed. The female patient who experienced postoperative urinary urgency, treated conservatively because of the lack of improvement, severity of the symptoms, was directed to urology (cystoscopy) consultation. The cystoscopy revealed diffuse leukoplakia of the bladder, the sites of leukoplakia were dissected and coagulated (this condition was not associated with the implantation of the tape). After the cystoscopy subjective improvement and a reduction in the urinary urgency was observed. The other two patients treated with anticholinergics: in one the urinary urgency was eliminated, in the second one it was significantly decreased compared with the preoperative period. Pelvic examination: in all patients the state was correct. Cough test negative – 100% of the respondents. The pain strength according to VAS: „0″, all the patients. Noticeable discomfort: two patients „4″ – slight discomfort, while the others „5″ – no discomfort, the average of 4.9.
After 6 months all the patients reported for the check-ups. there was no health deterioration, there were no symptoms that may have been associated with the surgery, there was no stress incontinence. None of the patients agreed to the proposed urodynamic study before the follow-up visit considering that the treatment process is complete. Pelvic examination: in all the patients the state was correct, cough test negative. Pain strength according to VAS: the patients estimated at „0″, noticeable discomfort at „5″ – 10%. The time to return to full active life after the operation ranged from 1 – 8 weeks, on average 2.9 weeks. The patients assessed that their condition improved after surgery.
Summary of the studies
In the study group of 20 patients with stress or mixed type of urinary incontinence during the 6 months from the implantation of the Dallop® NM urological tape by means of the TOT method, there were no significant intra – and postoperative complications associated with the implant. The tape was evaluated by three operators involved in the study as a handy, convenient to use and safe. The duration of the implantationof the Dallop® NM tape with access through the foramen obturatum access was short (on average about 20 min.). The pain and discomfort associated with the surgery in the patients was short, low-graded. Most of the patients returned to active life after the operation within 2 – 3 weeks, within six months all patients found their health as better compared with the preoperative period. Efficacy in the treatment of stress urinary incontinence in the study group was defined as 100% in terms of subjective (interviews collected from the patients) and objective (pelvic examination with a cough test) opinions.
- Based on the results of the six-month observation of the operated group of twenty women, the Dallop® NM urological tape can be considered as an effective, convenient for doctors and patients, and safe method for the treatment of stress urinary incontinence in women.
- In the examined group all the patients achieved good results of the surgical treatment and there were no complications associated with the surgical procedures and the implanted tape.