The next stage of modeling is transverse resection of the ureter in order to provide the required length for the correct application of the ureterocyst-anastomosis. The resected tissue of the ureteral wall is sent for histological examination, which is essential in determining the timing of postoperative splinting of the anastomosis and predicting the restoration of ureteral contractility.
At the next stage of the operation, a longitudinal oblique resection of the distal part of the ureter is performed. Depending on the patient’s age, the length of the longitudinal resection may vary, however, as a rule, it corresponds to the lower third of the ureter. ON THE. Lopatkin performs a duplication of the ureter, and not its resection in order to minimize trauma to the ureter and maximize the preservation of its neuromuscular elements. When performing duplication of the ureter, it is recommended to use interrupted sutures, and apply the ureterocystoanastomosis according to the principle of “non-spill inkwells”.
Suturing of the ureter along the lateral wall is performed using absorbable suture material in a continuous manner. The lumen of the ureter after modeling should ensure unimpeded passage of urine under conditions of reduced evacuation function, and its diameter should correspond to the size of the antireflux tunnel of the bladder wall. The further course of the operation does not differ from that of the standard technique for performing ureterocystoanastomosis. Immediately before the imposition of the anastomosis, the ureter is splinted with an intubating drainage tube of the required diameter (10-12 CH). Depending on the severity of sclerotic changes in the wall of the ureter, which is determined by histological examination, splinting of the ureter is carried out for a period of 7 to 14 days.
As a rule, histological examination reveals a sharp decrease in nerve and elastic fibers, pronounced sclerosis of the muscle layer with almost complete atrophy of muscle bundles, fibrosis of the submucosal layer, segmental ureteritis.
The effectiveness of ureterocystoanastomosis with megaureter, depending on the method of operation, is 93-99%.
With an extremely pronounced decrease in the secretory capacity of the kidney (insufficient secretion with dynamic nephroscintigraphy more than 95%), nephroureterectomy is performed.
In case of an immediate threat to the patient’s life due to renal failure or purulent-septic complications with megaureter, a “salvage” ureterocutaneostomy (suspended, T-shaped, terminal) is performed, which allows the patient to be taken out of a serious condition. Subsequently, after eliminating the main cause of the development of the megaureter, the closure of the reterocutaneostomy is performed.
An alternative method of urine diversion from the upper urinary tract is percutaneous puncture nephrostomy, which is considered less traumatic than ureterocutaneostomy. In the future, it is not necessary to perform repeated surgery to close the ureterocutaneostomy.
Recently, various minimally invasive methods of treating a megaureter have been more and more actively introduced:
- endoscopic dissection:
- balloon dilation;
- PMS stenting in obstructive megaureter;
- endoscopic introduction of bulking agents into the orifice of the ureter with refluxing megaureter.
However, the lack of data on the long-term consequences of minimally invasive methods of treating megaureter determines the limited application of these methods. The main application of minimally invasive methods is found in debilitated patients, in the presence of pronounced concomitant diseases and with other contraindications to conventional open methods of surgical treatment of the disease.
Thus, surgical intervention for neuromuscular dysplasia of the ureter is aimed at restoring the passage of urine from the pelvis through the ureter to the bladder, at reducing the length and diameter of the ureter without disrupting the integrity of its neuromuscular apparatus and eliminating VUR.
More than 200 methods of correction of the ureter with its dysplasia have been proposed. The choice of the method and method of surgical intervention is determined by the nature and degree of the clinical manifestation of the disease, the presence of complications, the general condition of the patient.
Conservative treatment of this malformation is unpromising. It can be used in the preoperative period, since with the most careful selection of antibacterial agents, it is possible to achieve remission of pyelonephritis for several weeks and very rarely for several months.
However, when establishing the normal function of the kidney (radioisotope research methods), it is advisable to temporarily abandon surgical treatment, since it is extremely difficult to carry out differential diagnostics between neuromuscular dysplasia of the ureter, functional obstruction of the ureter, disproportion of its growth in young children.
If the loss of kidney function is ascertained, surgical intervention is indicated.
Palliative operations (nephro-, pyelo-, uretero- and epicystostomy) are ineffective; radical methods of treatment of neuromuscular dysplasia of the ureters are shown. The best results are obtained in patients operated on in stages I and II of the disease. The overwhelming majority of patients are sent to the clinic for urological examination and treatment in the III or II stage of the disease. In stage III, the indications for surgery are relative, since at this time the process in the kidney and ureter is almost irreversible. Consequently, the effectiveness of treatment for megaloureter can be increased, first of all, by improving the diagnosis of this malformation, that is, by a wider introduction of uroradiological examination methods into the practice of somatic children’s hospitals and polyclinics. Surgical intervention is indicated at any age after diagnosis and preoperative preparation according to general requirements. Expectant tactics for this disease are unjustified. Plastic surgeries give the better results the earlier they are performed.
Nephroureterectomy is used only in case of irreversible destructive changes in the kidney, a sharp decrease in its function and the presence of a healthy contralateral kidney.
AND I. Pytel, A.G. Pugachev (1977) believe that the main tasks of reconstructive plastic surgeries for neuromuscular dysplasia of the ureter are excision of the ureteral area that creates an obstacle, modeling the diameter of the ureter to a normal caliber, neoimplantation into the bladder and antireflux surgery.
Experience shows that simple reimplantation of the ureter fails to create a satisfactory functioning opening, since the entire complex anti-reflux mechanism is damaged during resection of the distal ureter. Surgical intervention should be aimed at normalizing urodynamics and eliminating VUR. Direct or indirect ureterocystoneostomy without antireflux correction in most patients is complicated by VUR, which contributes to the progression of irreversible destructive processes in the renal parenchyma. Antireflux surgery can be successful if a long submucosal canal is created. The diameter of the reimplanted ureter should be close to normal. Therefore, during the reconstruction of the ureter, it is not enough to perform resection of the excessive length of the ureter.
The following operations are most widespread.
BischotT operation. The corresponding half of the bladder and the pelvic part of the ureter are mobilized. The ureter is dissected, preserving the pelvic region. The widened part of the distal ureter is resected. A tube is formed from the remaining part of the ureter and sutured with the preserved segment of the intramural ureter. With a bilateral anomaly, the operation is performed on both sides.
J. Williams after resection of the megaloureter implants the ureter into the wall of the bladder in an oblique direction, creating a “cuff” from the wall of the ureter.
Operation according to V. Gregor. An inferior pararectal incision is performed. The peritoneal sac is peeled off in a blunt way and retracted in the opposite direction. The ureter is exposed and excreted extraperitoneally from the opening in the bladder. Then the posterior wall of the bladder is isolated and dissected to the mucous membrane from the confluence of the ureter towards the apex at a distance of 3 cm. The ureter is placed in the wound, and the wall of the bladder is sutured over it with knotty sutures. The wound is sewn up tightly.
V. Politano, V. Leadbetter, the reimplanted ureter is first carried out for 1-2 cm under the mucous membrane of the bladder and only then brought to the surface and fixed.
Some authors excise the narrowing of the ureteral opening and suture its end in the formed opening of the bladder wall.
Operation according to N.A. Lopatkin A.Yu. Svidler. After the formation of the ureter according to the method of M. Bishov, it is immersed under the serous membrane of the descending colon, that is, ureteroenteropexy is performed. According to the authors, the ureter “gets used” well into the surrounding tissues, and a vascular network is formed between the intestine and the ureter, providing additional blood supply to the ureter. The disadvantage of this operation is that it can only be performed on the left side. On the right, diving can only be anti-peristaltic, which disrupts the passage of urine. In addition, this operation does not eliminate the expansion of the lower cystoid of the ureter. A significant drawback of this method is the need for complete mobilization of the lower cystoid of the ureter, which leads to complete avascularization and denervation.
Given these shortcomings, N.A. Lopatkin, L.N. Lopatkina (1978) developed a new method of surgery, which consists in the formation of an intramural valve while maintaining vascularization and innervation of the ureter, its muscle layer, as well as narrowing the lumen of the expanded part to a slit-like one by duplicating the ureter.
Operation according to N.A. Lopatkin-L.N. Lopatkina. An arcuate incision is made in the groin area. The upper corner of the cut may extend as far as the costal arch. The dilated part of the ureter is mobilized. A feature of this stage is the extremely careful attitude to the vessels of the ureter. The most affected area, which has lost contractility (usually the lower cystoid), is resected not along the border of the intercystoid narrowing, but retreating by 1 cm, that is, along the lower cystoid. A duplication of the ureter is formed along the remaining dilated cystoids (with complete preservation of its vessels) on the tire with a continuous suture with chrome-plated catgut, starting from the intercystoid narrowing. The seams should be close together. A feature of ureterocystoanastomosis is the formation of an antireflux roller from the flap of the lower cystoid of the ureter (in front of its opening). The opening of the ureter resembles a cochlea-like formation. Thus, the duplication of the ureter narrows its lumen, and the formed blind canal serves as an anatomical valve: at the time of urination or when the intravesical pressure rises, the urine stream rushes to the ureter and fills both of its canals. The blind canal, overflowing with urine, comes into contact with the through channel with its walls and blocks the flow of urine from the bladder to the pelvis.
The operation proposed by N.A. Lopatkin and L.N. Lopatkina (1978), qualitatively differs from interventions based on resection of the ureter in width. The authors achieve a narrowing of the lumen of the ureter not by cutting out a strip of one width or another, but by creating a duplication of the ureter. This technique has several advantages. Resection in width over a considerable extent disrupts the blood supply to the abnormal ureter. When a long wound surface is scarred, the ureter turns into a rigid tube with sharply impaired contractility. The formation of a duplication of the ureter does not disturb its blood supply, and due to the “doubling” of the wall, the peristaltic activity of the ureter is somewhat enhanced. During neoimplantation, the “doubled” wall of the ureter, forming a roller around the artificial opening, prevents reflux.
A.V. Lyulko (1981) performs this operation as follows. With a club-shaped incision, the ureter is exposed extraperitoneally and mobilized along the dilated part. Then, retreating 2 cm from the wall of the bladder, the lower cystoid of the ureter is resected and its distal end is invaginated through the opening into the bladder. Throughout the remaining dilated cystoids of the central segment of the ureter, while preserving its mesentery and vessels, a duplication is formed by imposing a continuous catgut suture on the bus. After that, the central end of the ureter is guided into the bladder through its invaginated distal end using a specially created clamp. Both ends are sewn with knotty catgut sutures. If the distal end of the invaginated ureter is very narrow and it is not possible to draw the end, it is dissected along its length and additionally with separate catgut sutures is fixed to the duplication of the ureter.
A.V. Lyulko, T.A. Chernenko (1981) conducted experimental studies, which showed that the formed “papilla” does not atrophy, but flattens and becomes covered by the epithelium of the bladder. Even with the creation of high intravesical pressure, the formed anastomosis in most cases prevents the occurrence of VUR.
It is extremely difficult to draw up a treatment plan for patients with bilateral neuromuscular dysplasia of the ureter in stage III of the disease with symptoms of chronic renal failure. Such patients can be operated on in two stages. First, nephrostomy is applied, and then radical surgery is performed on the distal ureters. In recent years, this tactic has been abandoned. First, intensive detoxification therapy, antibacterial treatment, and forced frequent urination are performed.
After some improvement in the condition, a decrease in the activity of the symptoms of pyelonephritis, a radical operation is performed, followed by a longer drainage of the operated ureter and bladder. In such patients, simultaneous surgery on both sides is effective, since in the postoperative period there is a very high risk of exacerbation of pyelonephritis or the development of its purulent forms in the kidney drained by the unoperated ureter. In those cases when the patient’s condition does not allow to simultaneously perform corrective surgery on both sides, a nephrostomy tube is applied on the second side.
Surgical intervention for neuromuscular dysplasia of the ureters should be considered as one stage in complex therapy. Before and after the operation, patients should be prescribed anti-inflammatory drugs strictly under the control of antibiotics. Young children (up to 3 years old) and older children with clinical manifestations of chronic renal failure in the immediate postoperative period, in addition to intensive antibacterial treatment, are shown infusion therapy for 5-7 days. It is necessary to control and correct the electrolyte composition of blood plasma, normalize the acid-base state. Blood transfusions are shown in fractional doses depending on the age of the child with an interval of 2-3 days, vitamin therapy. In order to more quickly sanitize the upper urinary tract, it is necessary to rinse the drainage tubes introduced into the ureters and bladder with a solution of dimethyl sulfoxide or other antiseptics. After discharge from the hospital, patients should be under the dispensary supervision of a urologist, and pediatric patients should be under the supervision of a pediatrician. Every 10-14 days, continuously for 10-12 months, it is necessary to carry out antibacterial treatment with a change of drugs, preferably based on the data of bacteriological analysis of urine and antibioticogram.
It is advisable to combine oral administration of antibacterial agents with their local use by iontophoresis (iontophoresis of antiseptics, potassium iodide, neostigmine methyl sulfate, strychnine, inductothermy, electrical stimulation). The appointment of hyaluronidase, pyrimidine bases, aloe and other biogenic stimulants in the postoperative period helps to improve the blood supply to the operated ureter, reduce sclerosis and enhance reparative processes in the wall of the urinary tract and in the surrounding tissues.
Dispensary observation of patients who have undergone surgical treatment should be carried out by a urologist and nephrologist, and pediatric patients should be monitored by a pediatrician. Good patency of the PMS and the absence of exacerbations of pyelonephritis within 5 years allow the child to be removed from the register.
The postoperative prognosis for megaureter depends largely on the preservation of renal function.
VUR is a pathogenetic term that reflects the process of retrograde flow of urine from the bladder into the upper urinary tract. VUR is one of the most common diseases of the urinary system, especially in children.
VUR is a polietiologic disease.
The main cause of primary VUR is a congenital malformation of the orifice of the ureter:
- persistent gaping of the orifice (“funnel-shaped” configuration of the orifice of the ureter): o the location of the orifice of the ureter outside the Lieto triangle (dystopia of the orifice of the ureter);
- short submucosal tunnel of the intravesical ureter;
- doubling of the ureter;
- paraureteral diverticulum. The main causes of secondary VUR:
- organic IVO (valve or stricture of the urethra, sclerosis of the bladder neck, stenosis of the external opening of the urethra);
- dysfunction of the bladder (GMF, detrusor-sphincter discoordination);
- inflammation in the area of the Lieto triangle and the orifice of the ureter (with cystitis);
- wrinkling of the bladder (“microcystis”);
- iatrogenic damage to the area of the Lietot triangle and the orifice of the ureter (operations with dissection of the smooth muscles of the detrusor or impact on the orifice of the ureter: ureterocystoanastomosis, bougienage of the ureteral orifice, dissection of the ureterocele, etc.).
It is impossible to understand the reasons for the development of PMR without understanding the normal structure of the PMR. Anatomically, the closure function of the PMS is achieved due to the ratio of the length and width of the intravesical ureter (5: 1), the oblique passage of the ureter through the bladder wall. The long submucosal tunnel is a passive element of the “ureterovesical valve”. The active element of the valve mechanism is represented by the musculo-ligamentous apparatus of the ureter and the Lietot triangle, which closes the orifice when the detrusor contracts.
The causes of non-physiological urine flow include pathological conditions leading to a violation of the PMS closure mechanism and high intravesical fluid (urine) pressure. The first include congenital malformations of the PMS and the inflammatory process in the area of the superficial or deep triangle of the bladder (cystitis), which disrupts the function of the detrusor or directly the PMS itself.
Anomalies of the vesicoureteral junction are often the result of abnormal development of the ureteral outgrowth of the Wolf’s duct at the 5th week of embryogenesis. Types of vesicoureteral anomaly:
- wide, constantly gaping shape of the ureteral orifice:
- the location of the orifice of the ureter outside the zone of the bladder triangle (lateroposition);
- complete absence or shortening of the submucosal tunnel of the vesicoureteral junction;
- violation of the morphological normal structure of the vesicoureteral junction (dysplasia).
Loss of the closure function of the vesicoureteral junction occurs with inflammation of the bladder wall or the PMS zone. Most often, secondary VUR is a consequence (complication) of a bullous (granular) or fibrinous form of cystitis. Urinary tract infection occurs in 1-2% of boys and 5% of girls. More often the urinary tract is colonized by conditionally pathogenic (intestinal) flora, among which the main place is occupied by Escherichia coli (40-70%).