What is an anal fistula? The full name of an anal fistula is anorectal fistula, which is commonly referred to as a fistula, or in Chinese medicine, an anal leak.
In Chinese medicine, it is also called a fistula. In the sense of the word, a fistula is a tube in the body that is formed when a lesion breaks outward. A fistula is a tube formed when the soft tissues around the anorectum become infected with pus and collapse outward or are cut open artificially. The inner mouth of the canal is the entrance to the infection, and more than 90% of them are located in the anal sinus at about 100px from the anal opening. The external opening of the canal is the ulcer or surgical incision, mostly outside the anus, but rarely also inside the anus and in the rectal wall.
Anal fistula is a common anorectal disease, accounting for about 10% of anorectal morbidity in China, and is common in young adults aged 20 to 40 years old, and is not uncommon in infants and children. Its effects on the human body are repeated perianal infections, swelling and pain, and scarring of the perianal tissue.
The difference between a complex anal fistula and a high anal fistula is based on the number or length of the fistula and whether it is curved. As mentioned earlier, the fistula starts as one, and with the development of the disease, there can be more than one. The difference between simple and complex fistulas is that they are very different in terms of treatment.
There are deep and shallow fistulas, deep ones we call high anal fistulas and shallow ones we call low anal fistulas, so what is the clinical basis for determining whether they are high or low? The fistula is mainly based on whether or not it crosses the anal raphe, a group of muscles that close the pelvic floor, 100px from the edge of the anus, around the periphery of the junction of the anal canal and rectum for a week.
The main reason for the formation of anal fistula is the late lesion of perianal infection, and the main reason for the formation of perianal infection (abscess) is the decrease in body resistance caused by various factors.
The reasons why perianorectal abscesses do not heal themselves and form anal fistulas after ulceration are generally considered to be the following.
① Perianorectal abscesses break or incision is mostly outside the anus, and pus flows from the external mouth, but the primary infection is mostly in the anal sinus. The anal sinus is then the portal for continued infection because the anal sinus opens upward and is open in the rectal cavity, and both bacteria and intestinal contents can enter the pus cavity through the anal sinus, causing repeated infection and the formation of a fistula.
②Fistula tracts pass between the anal sphincter, and because the sphincter is often constantly contracting and diastolic, it affects the discharge of pus and is easily infected with pus storage and difficult to heal.
③After the abscess breaks down, the pus is discharged, the pus cavity gradually shrinks, and the cavity wall forms a hard duct wall with proliferation of connective tissue, which cannot heal.
The fistula tract is bent, or has branches, poor drainage, and repeated infections, causing the fistula tract not to heal.
The fistula is accompanied by a history of painful ulceration and pus flowing next to the anus in varying degrees, and after the formation of the fistula, the painful pus flowing next to the anus will recur from time to time.
Another clinical manifestation of anal fistula is the presence of hard masses in the anal area. In addition, long-term pus irritation can lead to perianal dermatitis or eczema, causing itching in the anus.
If the fistula is not healed for a long time, it will also cause defecation difficulties, anemia, body wasting, mental depression and neurological weakness.
The only way to finally solve the anal fistula is through surgery. Therefore, there is no possibility of self-healing for anal fistulas and paranal abscesses once they occur, regardless of their severity, and medication will only alleviate the symptoms, and the only way to achieve clinical cure is through surgical (including wire) treatment. There have been many attempts to treat fistulas and perianal abscesses with methods other than surgery, but they have all ended in failure, to say the least, and so far no non-surgical methods have been found to cure them.
The purpose of anal fistula surgery is to cut open the fistula, remove the internal mouth, completely eliminate the source of infection, allow the fistula to drain freely, and allow the new granulation tissue to grow upward from the bottom of the wound and gradually fill the wound.
The first thing you need to do is to get a good idea of what you are getting into.
To summarize these cancer cases, they generally have the following characteristics: ① history of anal fistula for more than 10 years; ② anal discharge with odor and sometimes mucin-like; ③ hard local anal tissue and obvious pain.
The cause of anal fistula cancer is still not well understood, but it is generally believed to be due to the destruction of lymphatic structures in the area and the reduction of immune guardianship ability to inhibit intercellular degeneration or malignant degeneration. The fundamental way to prevent anal fistula from becoming cancerous is to treat it in time.
The significance of early treatment of anal fistula is that one can prevent anal fistula from becoming cancerous, the second can reduce the local repeated septic formation of multiple fistulas and increase the difficulty of treatment, the third can reduce pain and protect the anal function is not affected.
The first is the possibility of cancerous fistulas, which is not uncommon in recent years. In recent years, such cases are not uncommon in clinical practice. When an anal fistula becomes cancerous, it is usually difficult to preserve the anus because it is located in the anal area. Therefore, the only way to prevent anal fistula from becoming cancerous is to treat it as early as possible.
The majority of fistulas start out as simple fistulas, but as the disease recurs, one becomes a complex fistula with multiple fistulas, and the other develops deeper into a high fistula, making surgery more difficult.
As the number of fistulas increases and their location goes up, not only is the scar around the anus heavier, but the muscle ring outside the anus and rectum must be cut off during surgery to achieve healing, which is not only more painful and takes longer to heal, but most importantly, the function of the anus will be affected, leading to varying degrees of anal incontinence.
The actual fact is that you can find a lot of people who are not able to get a good deal on a lot of things.
The fistula is a deeper fistula that passes through the anal raphe, and according to the conventional surgical principles of anal fistula, the fistula is opened by cutting all along the fistula from the inner to the outer mouth, then most of the internal and external anal sphincter and anal raphe will be cut off, so the fistula will be cured, but it will cause different degrees of anal incontinence, and there are many literature reports on this at home and abroad. If the function of the anus is taken into consideration and not sufficiently cut, the recurrence rate will be high. A Japanese scholar reported that 831 cases of recurrence (21.2%) out of 3916 cases of anal fistula treated by him. This contradiction between efficacy and anal function is a major problem in the treatment of high anal fistulae, especially in foreign countries. High anal fistula is currently a recognized medical problem at home and abroad.
The first time this was done was in the Ming Dynasty, when it was documented in the book “Ancient and Modern Medical Streams”. The method at that time was to pass the fistula, sphincter and skin all through the line and hang off, not only the course of treatment is long, and painful, and then after continuous improvement, most of what is used now is the combination of hanging wire and surgical incision to form the incision hanging wire therapy, this method is outside the anal edge of the fistula, branch, anal edge skin and shallow sphincter these will not affect the function of the anal tissue once cut, the internal mouth of the anal fistula, deep This can reduce the pain to a certain extent and shorten the course of treatment.
The reason why threads are used is that after the anal sphincter and anal raphe are cut, the muscles contract and the broken ends of the muscles separate, causing the loss of the sphincter function and the obstruction of anal closure. The hanging thread is an “elastic ligature” that slowly disconnects the muscle and causes adhesion between the severed end of the muscle and the surrounding tissue through fibrosis caused by inflammation, thus preventing the severed end from retracting and avoiding fecal incontinence.
Nevertheless, there are still some shortcomings of the hanging method, such as heavy postoperative scar, deep scar sulcus, possible leakage of fluid from the intestinal cavity, and easy recurrence. At the same time, the pain of the patient during the hanging period is still very great and can be said to be unbearably painful at times. These problems are still to be solved.
9, the solution to complex anal fistula mentioned earlier that the previous anal fistula surgery is done in accordance with the surgical principle of cutting all along the fistula from the inner to the outer mouth, this method is more suitable for simple anal fistula with only one fistula, but for complex anal fistula with more than two, if this is done, then the anus will be cut in many places, which will inevitably cause deformation, displacement, sphincter relaxation and many other serious The problem is that the main focal incision is used to treat the fistula. To address this problem, the use of primary focal incision and counter-oral drainage can be a good solution to the problem of anal injury.
Although complex anal fistulas have more than two external or curved fistulae, the majority have only one internal port, and the other external ports are connected to this internal port. This internal port and the fistula in the anal canal segment are the source of morbidity, which we call the main focus, and are therefore the focus of treatment. The rest of the fistulae leading to the external orifice we call branched. Therefore, he broke with the previous surgical principles and only cut the main focal point, leaving the branched canal open and the external orifice open and dilated. This not only cuts off the source of infection in treatment, but also allows the drainage to flow freely, so that the fistula can be cured quickly, and in terms of trauma, it is only a simple anal fistula injury, so the clinical function of the anus is not affected.
High anal fistula is an intractable anorectal disease, and reducing the postoperative recurrence rate and avoiding different degrees of anal incontinence are urgent clinical problems to be solved. In recent years, the author has treated several common high anal fistulas with the combined application of incision, fistula ligation, glue tube drainage and fistula openings with satisfactory results, which are described below.
I. Treatment methods.
1, no external mouth simple high anal fistula outside the anal verge no rupture mouth, the starting point of the fistula in the tooth line, to the rectal wall, can be straight up and down, but also from 6 points, to one side of the rectum oblique up extension. This is the most common type of high anal fistula.
The procedure is performed by making an outward radiating incision perpendicular to the anal canal at the beginning of the dentate fistula, with the outer end at the anal verge, and cutting out the skin inside the incision. A small curved hemostat is used to bluntly separate the muscle tissue around the fistula from the dentate line to the fistula. Prepare four No. 10 silk wires, tie one end together with a knot, send them into the intestinal cavity with the index finger on top, dock them with the hemostatic forceps that previously probed the intestinal wall, slowly open the hemostatic forceps and clamp the end of the wire, withdraw the forceps to introduce the wire into the fistula, pull it out of the internal opening to tighten it, and tie it with force. A latex tube with a lateral hole is placed into the fistula and used for daily postoperative flushing of the pus cavity.
Seven days after surgery, if the fistula is not incised, the ligature wire is cut and three 10-gauge silk threads are still used, guided through the fistula by the lead left during the first surgery and ligated firmly, and the fistula is completely incised in about 3 to 5 days and the ligature wire falls off by itself.
2, there is an external mouth simple high anal fistula outside the anal verge with an ulcerated mouth, and the external mouth, internal mouth and high fistula are basically in a straight line.
Surgical method: Make a radial shuttle-shaped incision around the external opening with the anus, extending the outer end 25px outward to the external opening and the inner end to the anal verge, and cut out the skin inside the incision. A probe is used to enter the external orifice and the fistula is incised along the probe to the dentate line. The wound is hemostatic. The treatment of high fistula on the internal port is the same as the surgical method of “simple high anal fistula without external port”.
3, complex high anal fistula with external mouth outside the anal verge see more than two external mouth, or low fistula bending, external and internal mouth is not in the same point, that is, the low part of the complex fistula. Above the dentate line is a single fistula.
Clinical observation is that 80% of high anal fistulas are usually located at the 6:00 dentate line in the truncated position. Select the closest external orifice to the internal orifice, probe into it, cut the fistula along the probe to the internal orifice at the dentate line, construct the skin margin on both sides of the incision, and stop the bleeding. The other external orifice is reopened and a latex tube or latex strip is placed between the two external orifices or between the other external orifice and the main focal incision to drain the fistula, which is usually removed in 5 to 7 days. For curved fistulas with only one external opening, a shuttle-shaped incision can be made outside the anal verge at the same location as the internal opening, and the fistula can be incised to the dentate line, and a latex tube or strip can be placed between the external opening and this incision to drain the fistula, again removed in 5-7 days.
The treatment of high fistula is the same as the surgical method of “simple high anal fistula without external opening”.
4, high horseshoe fistula low fistula is simple or complex, there are more than two fistulas above the dentate line, most of the internal mouth in the 6-point dentate line, the fistula is divided into the left and right sides to extend forward and up. This type of fistula can be palpated in a semi-annular stripe at the location of the rectal ring.
The surgical approach: below the dentate line (low fistula part) is a simple one, referring to the “simple high fistula with external opening” approach, while below the dentate line (low fistula part) is a complex one, referring to the “complex high fistula with external opening” approach. One side of the fistula above the dentate line (high fistula part) is treated according to the “simple high fistula without external opening” method. The other side of the treatment method is mostly the same as the “simple high anal fistula without external mouth” surgical method, but the difference is that the silk wire set into the fistula is not ligated temporarily, take a false hanging and placed into the latex tube drainage, and then tighten the wire ligated after one side is disconnected, and finally dissect this side of the fistula.
Second, the so-called high-grade anal fistula.
It is an anal fistula located above the plane of the anorectal ring and has been considered the most difficult anorectal disease to treat because it involves the core structure of the anus, the anorectal ring. Currently, there are two types of surgical treatment: sphincter severance and sphincter preservation.
The sphincter-preserving procedures are as follows
(1) Coring-out method: The Coring-out method created by Parks in 1961 for the treatment of high anal fistulas has become the basis of modern sphincter preservation surgery. The method is based on the doctrine of anal gland infection in the formation of anal fistula.
(2) Hanging the floating thread: first cut the infected anal sinus at the dentate line, then hang the thread for fistula and sphincter, but do not tighten it, and only use the drainage and foreign body stimulation of the thread to fully drain the fistula and inflammatory gap. When the gap and the fistula are filled with granulation, the sphincter is rotated or rubber banded, without strangling the sphincter, to maintain the integrity of the sphincter. However, the recurrence rate of the virtual hanging method is high. Buchaman of StMark Hospital reported that they applied a short-term hanging drainage method to treat complex anal fistulas with a high recurrence rate at 6, 15, and 60 months follow-up. Williams treated 14 cases of high anal fistulas with a recurrence rate of 14%.
(3) Excisional mucosal flap: Aguilar et al. were the first to apply excisional mucosal flap to the treatment of anal fistulas. He used a probe to insert the fistula and cut the skin and mucosa of the anal canal up to the internal orifice. The end of the anal canal is sutured and the outside wound is opened for drainage. The efficacy of this procedure is still controversial, and some studies have reported a high recurrence rate in recent years.
(4) Biopatch endograft repair: Jamshidi R, Scheeter WP performed fistula repair with biopatch (mammalian membranous material) in 6 patients with open injuries, and the fistula was closed in 5 cases. Thus, biological patches have been used to repair the defect of the internal orifice of anal fistulas. Using the properties of biological patches, they can counteract intestinal hypertension, prevent bacteria and infections from entering the source of the fistula through the internal orifice, close and reinforce weaknesses, act as a substrate filling, and act as a stent guide.
(5) Bioprotein gel sealing: When medical bioprotein gel comes in contact with the fistula wound, it can quickly form a clot and effectively fill and close the defective fistula. It is biocompatible, has no local foreign body reaction, and can be absorbed by the tissue in about 2 weeks without being discharged from the fistula. The method is simple and easy to perform, and provides a new method for the treatment of high anal fistula.
(6) Tunnel dragging: Tunnel dragging is done by using a probe to probe through the outer entrance of the fistula, penetrating the inner and outer entrance and introducing 10 strands of medical silk into the main fistula depending on the size of the fistula, with the ends needing to be knotted to keep the silk loose. The fistula was opened by the fistula, and the 10 strands of medical silk were introduced into the main fistula, depending on the size of the fistula.
It is worth noting that the sphincter preservation surgery because of the preservation of the sphincter, so it is difficult to achieve drainage patency, so the cure rate is lower, most hospitals at home and abroad still use the sphincter severing surgery.
The sphincter cutting surgery style are.
(1) low cut high hanging method: low fistula tract cut high fistula tract hanging line, first partly cut the part below the anal canal rectal ring, the part above the anal canal rectal ring using the hanging line method. The low-cut-high-hanging method avoids the pain of cutting open all the tissues and has the advantages of shortening the treatment course, reducing scarring and damage, and maintaining good function.
(2) Cut-and-hang partial suturing: After finding the internal opening and the line and number of fistulae, the branch canal is cut, the necrotic tissue is scraped off, the canal wall is excised, full suturing is performed, the internal opening is cut, the main line is half cut, and the anal canal is hung with the rectal ring. However, because the canal is deeper and the suture tension is high, a dead cavity can remain and secondary infection can occur.
(3) incision and hanging open sutures: only the infected anal glands and sinuses are removed, and the fistula formed by the infection at its upper end is subliminally enlarged, the fistula wall is stripped, and the fistula is kept open to drainage.
In a comprehensive analysis of the above two types of surgery, sphincter preservation means that there is recurrence, and sphincter severance means that there is anal injury.
The author believes that anal fistulas, especially high anal fistulas, are difficult to treat because of the variability of the internal orifice, the shape, distribution, and number of fistulas, and the relationship between the fistula and the sphincter, followed by the problem of the rectal ring. Therefore, the treatment cannot be classified simply by the preservation of the sphincter or not. It is necessary to minimize the damage to the anorectal local tissues and protect the normal anal function under the premise of ensuring the treatment effect according to the specific situation. Clinically, based on the observation of a large number of cases, the author divided high-grade anal fistulas into four categories and proposed the treatment principle of opening the main foci and draining the fistulas, choosing four basic methods of incision, open placement, ligation and drainage, which are used alone or in combination according to different conditions with satisfactory results.
The main focus is not simply the internal orifice, but the internal orifice and the segment of the fistula connected to it; in the case of a low-level fistula, the main focus is the internal orifice plus the segment of the fistula connected to it. In the case of a high-grade fistula, the primary focus is the internal orifice plus all of the high-grade fistulae. Openings are not simply incisions, either; low fistulas can be incised at once, and high fistulas can be opened slowly by hanging or ligating. Drainage is important for the healing of fistulas, either by direct incision or by slow and open opening, and requires the use of incision design, latex strips and latex tubing to allow drainage. If these two things are done, there will be no problem in healing the fistula.
Low-level fistula incision is a common practice in the treatment of anal fistulas at home and abroad, but two points should be noted when making the incision.
(1) The fistula is open and can be cut along the probe, but if the fistula is not open, do not probe hard to prevent a false channel from being probed and the incision deviating from the fistula. This must be done along the scar stripes of the fistula wall or along the necrotic tissue in the fistula.
(2) If there are multiple external openings or the fistula is curved, not all of the fistula can be cut, and part of the fistula is left open to protect the anus from deformation. The ends of the open fistula must be open to form a counter-oral drainage, and latex strips or latex tubes can be placed to assist in drainage. However, high fistulas on the dentate line should not be left open because they do not protect the function of the anus and may not heal for a long time.
The advantages of hanging a wire versus direct incision are undeniable, but I believe there are still two drawbacks. The pain is great and the scar sulcus is wide. The continuous strangulation of muscle and canal wall tissues by the glue line causes continuous local pain and downward movement of the anus, and the second and third postoperative tightening of the line also causes severe pain. Replacing the glue line with silk ligation can greatly reduce this pain, and patients usually have pain only within 1 to 2 days after surgery. In addition, the cutting surface of the silk wire is smaller than that of the glue wire, so the width of the postoperative scar sulcus is also relatively small.
The role of drainage in the treatment of anal fistulas is often overlooked, and the root cause of many long-standing fistulas is the failure to address drainage issues. High-grade fistulas, even when hung, must be placed in latex tubes and flushed daily so that they can grow as they are cut. Latex tubes must be used inside the anus, while fistulas placed openly outside the anal verge can use latex strips or latex threads, which can reduce the stimulation of local tissues by latex tubes and reduce pain.
Based on the traditional hanging wire method, this method identifies and treats fistulas and combines multiple methods to complement each other’s strengths and weaknesses, effectively reducing the recurrence rate and mitigating the damage to the anus, providing new ideas and approaches for the treatment of high-grade anal fistulas.