Anal fissure
Anal fissures are small ulcers formed after the skin layer of the anal canal below the dentate line has been fractured in a direction parallel to the longitudinal axis of the anal canal and are about 0.5 to 1.0 cm in length. In contrast, surface fissures of the anal canal cannot be considered as anal fissures because they heal quickly on their own and are often asymptomatic. Anal fissure is a common anal canal disorder and a common cause of severe pain at the anal canal in young and middle-aged people. Anal fissures are most commonly seen in middle-aged adults, but can also occur in the elderly and in children, generally slightly more in men than in women, although more women than men have been reported. Anal fissures often occur in the posterior and anterior middle of the anus, with the posterior part of the anus being the most common and the sides less common. Initially, there is only a small fissure on the skin of the anal canal, sometimes it can crack into the subcutaneous tissue or up to the superficial layer of the sphincter, and the fissure is linear or prismatic.
New theory of anal fissure – the theory of embolism
The theory of embolism refers to the formation of anal fissure when the anal canal dilates beyond its limit and the skin of the anal canal is fractured in its entirety due to embolism (various primary lesions) in the anorectum.
1. Hypothetical reasoning
A block is embedded in the anorectum, and the block hinders the discharge of stool.
If we consider internal hemorrhoids, rectal tumors, enlarged anal papillae, and constipated fecal masses as embedded masses in the rectum, they also lead to anal fissures.
In other words, why can’t we consider various primary lesions such as hemorrhoid nuclei, rectal tumors, enlarged anal papillae, and constipated fecal masses as an intrarectal mass? This is the new concept of anal fissure etiology_embedding theory.
2.Comparison and verification Comparison with the traditional theory:
(1)The anatomical theory of anal fissure says that the anatomical structure of the anorectum is the congenital condition that anal fissure is prone to occur in a special part of the anus, but not the direct factor in the formation of anal fissure, i.e. without the embedded factor there is no root cause of anal fissure.
(2) Trauma is the direct factor of the condition of trauma, and trauma is the result of the obstruction of defecation by the “embedment factor.
(3) The infection theory of anal fissure says that infection can be secondary to the formation of anal fissure and is a condition for the transformation of anal fissure into chronicity.
(4) The internal sphincter spasm theory says that chronic inflammation stimulates the internal sphincter spasm and the narrowing of the anal canal are pathological changes in the process of development of anal fissure after its formation, but are not the cause of anal fissure.
3.Clinical verification
In clinical research, the author has thoroughly treated various primary pathologies such as internal hemorrhoids, enlarged anal papillae, rectal tumors, constipation, etc. and other factors of embolism based on the “theory of embolism” and the treatment principle of “use of ventilation”, and has received curative effects.
In summary, the author believes that the “embolism theory” is better than other theories in summarizing the pathological factors of anal fissures, explaining the occurrence of anal fissures, and guiding the treatment of anal fissures. The author believes that the theory of “embolism” is of high academic and clinical value in studying the formation of anal fissures.
Symptoms
The clinical symptoms of anal fissure are pain and bleeding.
Anal fissures often occur in the posterior and anterior middle of the anus, with the posterior part of the anus being the most common and the sides less common. At first, there is only a small fissure on the skin of the anal canal, sometimes it can be cracked to the subcutaneous tissue or to the superficial layer of the sphincter, and the fissure is linear or prismatic, if the anal canal is opened, the fissure wound becomes round or oval. The pain is characteristic, i.e., sudden cut-like pain during defecation (due to feces cutting through the skin of the anal canal), followed by brief relief, and then prolonged anal pain (due to spasm of the anal sphincter after stimulation). It is common for patients to fear defecation due to pain, and a vicious cycle of “fear of pain —- tolerate stool —- dry stool —- more pain” occurs. The bleeding caused by anal fissures also varies depending on the extent of the torn blood vessels, and it is common to see cases of anemia due to long-term or massive bleeding from anal fissures.
If an anal fissure is not treated in time, it can lead to ulceration of the anal canal (fissure fibrosis, also known as old anal fissure), hypertrophy of the anal papilla (polyp-like tumor), sentinel hemorrhoids (skin hyperplasia) and three other conditions, which can also develop into anal sinusitis (chronic inflammation of the anus) and anal fistula (purulent inflammation of the anus). The first three are called the “five features of anal fissure”. There is also the possibility of becoming anal canal cancer due to long-term chronic inflammatory irritation.
Typical symptoms are pain, constipation, and bleeding. The pain is relieved briefly after the feces is expelled, but after a few minutes, the sphincter muscle spasms reflexively, causing intense pain for a longer period of time, which can be relieved by painkillers in some cases. Therefore, patients with anal fissures are afraid of defecation, making constipation even worse and forming a vicious circle. A small amount of bleeding may occur on the surface of the feces or drip blood after the fissure. The newly occurred anal fissure has neat, soft edges, shallow ulcer base, no scar tissue, red color and easy bleeding. Chronic anal fissures are deep and hard, grayish-white, and do not bleed easily. Below the fissure is the “anterior hemorrhoid”. Anal finger and anoscopy can cause severe pain and should not be performed.
Etiology
The occurrence of this disease is mainly related to the following factors.
1, anatomical factors: the external anal sphincter is superficial, starting from the tailbone and going forward to the back of the anus. It is divided into two bundles, which surround both sides of the anal canal forward to the front of the anus, and then unite with each other. Therefore, there are gaps in the front and back of the anus. And most of the anal levator muscle is attached to both sides of the anal canal, less in front and behind. It can be seen that the anterior and posterior sides of the anus are not as strong as the sides and are easily damaged. And downward and backward form an angle of nearly 90 degrees with the rectum. Therefore, the posterior part of the anal canal is heavily compressed by feces, and because the posterior part of the anal canal has insufficient blood circulation, poor elasticity and more distribution of anal glands, these are the factors for the occurrence of anal fissure.
2, trauma theory: dry and hard stool or foreign bodies are likely to cause damage to the skin of the anal canal, which is the main factor causing anal fissure.
3.Infection theory: mainly the anal fossa in the back of the anus is infected and the inflammation spreads to the lower part of the skin of the anal canal, resulting in the subcutaneous abscess breaking and becoming anal fissure.
4, internal sphincter spasm theory: due to injury or inflammatory stimulation of the anal canal, the anal sphincter is in spasm, resulting in increased tension of the anal canal, which is easily damaged into anal fissure.
5.The theory of narrow anal canal: the anal canal skin is delayed in development, generating narrow anal canal, which is easily damaged into anal fissure.
Pathology
The pathological tissue changes of anal fissure can be divided into four stages.
Initial stage: Anal fissures caused by the above factors begin with superficial injury to the skin of the anal canal or superficial ulceration, and the tissue around the wound is basically normal.
Ulcer-forming stage: there is undesirable granulation in the wound. The base of the wound is seen to have annular fibers and the skin of the wound edge is hyperplastic.
Chronic ulcer stage: old ulcers in the wounds and internal sphincter visible at the base of the planer.
Chronic ulcers combined with other pathological changes: on the basis of chronic ulcers, there are subterranean anal fistulas, etc. Chronic anal fissures are often combined with the following pathological changes.
(1) Anal papillitis: the upper end of the ulcer is connected to the dentate line and the inflammation spreads, often causing anal sinusitis and eventually forming anal papillomegaly.
② anal sinusitis: the infection spreads from the anal sinus, forming a small abscess under the skin of the anal canal, which breaks down to form an ulcer. The fissure first causes sinusitis.
③ Pyramidal ulcer: Anal canal skin fissures, after infection, form ulcers.
④ Anal comb sclerosis: i.e. thickening and hardening of the pectineal membrane, forming a comb sclerosis, which exposes the base of the ulcer, prevents the sphincter from stretching and affects the healing of the ulcer.
⑤ Latent fistula: fistulae are commonly found at the base of the anal sinus and are connected to the ulcer because the sinus becomes infected and purulent, forming a small abscess that breaks down.
⑥ Fissured hemorrhoids: The skin at the lower end of the fissure is altered by inflammation and the superficial venous and lymphatic return is obstructed, causing edema and tissue proliferation. Formation of connective tissue external hemorrhoids, also known as sentinel hemorrhoids.
Classification
The classification of this disease has not yet been unified at home and abroad, and there are 2-stage classification method and 3-stage classification method commonly used in clinical practice.
(1) 2-stage classification method.
(1) Early anal fissure (acute stage): fresh fissures, no chronic ulcers and mild pain;
(2) old anal fissure (chronic stage): the fissure has formed a chronic ulcer, and there is also anal papilla hypertrophy and skin prolapse, and the pain is severe.
(2) 3-stage classification.
①Stage I anal fissure: superficial longitudinal fissure of the anal canal skin with neat and fresh wound edges. Tenderness is obvious, and the wound surface is elastic.
②Stage II anal fissure: history of recurrent fissures. There is irregular thickening and poor elasticity of the traumatic margin. The base of the ulcer is purplish red or there is purulent secretion, and the surrounding mucosa is obviously congested.
Stage III anal fissure: the ulcer margin is hardened, the base is purple-red with purulent secretions, the upper end is adjacent to the anal sinus with an enlarged anal papilla, and the lower end of the trauma has fissured hemorrhoids or a subcutaneous fistula.
Complications】
If the fissure is not treated in time, the repeated inflammation and infection of the fissure will develop subcutaneously to the anal margin, and subcutaneous abscess and fistula will be formed.
Anal fissure is a common anal canal disease that affects people’s lives due to its long-term recurrent infections and a series of complications: 1.
1, ulcers: initially is the anal canal skin longitudinal fissures, linear or prismatic, soft and neat sides, shallow bottom elastic, repeated infection so that the fissures do not heal for a long time, the edge thickened, the base hard, gradually become deeper chronic ulcers, slight stimulation can cause severe pain.
2, sentinel hemorrhoids: the skin below the fissure due to inflammatory stimulation, so that the lymph and small venous reflux is blocked, causing edema and fibrous degeneration, forming skin flab of varying sizes, called sentinel hemorrhoids, also belong to connective tissue external hemorrhoids.
3.Anal sinusitis and anal papilla hypertrophy: it is the result of repeated stimulation of the upper end of the fissure by inflammation, and the papilla hypertrophy can be prolapsed out of the anus with fecal discharge significantly.
4, anal margin abscess and anal fistula: the fissure inflammation expands subcutaneously, coupled with sphincter spasm, causing poor drainage of the ulcer, secretions sneak into the anal margin subcutaneously, forming an abscess, pus breaks out toward the fissure, forming a subcutaneous fistula.
5.Pectineal thickening: the pectineal area is the narrowest area of the anal canal, and is a good area for anal comb sclerosis and anal canal stenosis. The thickened tissue under the pectineal area is called the pectineal belt. The inflammatory stimulation of anal fissure can make it thicken and lose elasticity, which hinders the healing of anal fissure, so the thickened pectineal belt should be cut when treating anal fissure.
Self-check]
How to determine if you have anal fissure
Anal fissure is an ulcer formed after the skin of the anal canal is cracked, with anal pain, bleeding, constipation and anal itching as the main symptoms.
Whenever there is a problem with the anus, the first thing that comes to mind is “do I have hemorrhoids”. This is the case for many people who have anal fissure bleeding, because they don’t understand the disease, so their doubts and worries increase day by day, and some people even think that it is a precursor of bowel cancer. In fact, the difference between anal fissures, hemorrhoids and intestinal cancer is quite obvious.
According to the introduction, the bleeding of anal fissure and hemorrhoid are both bright red, but each has its own distinctive features. In the latter case, the bleeding is usually more than 10 drops. In the case of bowel cancer, the bleeding is often dark red, mixed with mucus or pus blood, and the stool habit will change significantly, with more frequent stools and a feeling of urgency. If the diarrhea does not subside after medication, it is important to pay special attention. In addition, the three groups of people are different, as hemorrhoids and anal fissures can happen to people of any age, while rectal cancer patients are mostly middle-aged or elderly.
Anal fissure patients should not undergo anal finger examination
Anal finger examination is very effective in the diagnosis of many anorectal diseases and is easy to perform, so it is one of the common examination methods used by anorectologists. However, nothing is foolproof, and the anal finger is no exception. For example, the anal finger cannot be used to examine anal fissures.
The typical symptoms of anal fissures are pain, constipation, and bleeding. The pain is relieved for a short time after the feces is expelled, but after a few minutes, the sphincter muscle spasms reflexively, causing intense pain for a longer period of time, which can be relieved by painkillers in some cases. Therefore, patients with anal fissures fear defecation, making constipation even worse, forming a vicious circle.
Self-examination method of anal fissure at home
The clinical manifestations of anal fissure mainly include pain, bleeding, constipation, anal itching and other symptoms. We can use these symptoms of anal fissure [4] for self-examination at home, and if you have these symptoms, then go to the hospital for treatment. Whether it is painful: its main manifestation is severe, persistent and severe pain, which can continue to increase and can be relieved automatically after a few hours. Whether bleeding: When defecating, damage to the trauma surface can cause bleeding from the fissure.
[Diagnosis
The symptoms of anal fissure have clear characteristics, and diagnosis is not difficult with detailed interrogation of the history and course of the disease, as well as pain and bleeding characteristics. However, in order to improve the accuracy of diagnosis and prevent errors, the differential diagnosis should be strictly based on examination, palpation, visual examination and histopathological biopsy.
Visual examination: in acute anal fissure, secretions are visible in the anus, and the lower end of the fissure can be seen by holding the buttocks open.
Finger palpation: due to sphincter spasm anal tightening, such as excessive force, often cause severe pain, sometimes must be examined under local anesthesia. The fissure is palpated in the anus, with soft edges, shallow base and elasticity in acute cases, and sensitive to touch; in chronic cases, the edges are hard and raised, with deep base and no elasticity.
Speculum examination: oval ulcers are visible, or small fissures are seen. In acute fissures, the fissures have neat edges and a light red base; in chronic fissures, the fissures have uneven edges and a dark grayish base, and in some severe fissures, the sphincter fibers can be seen.
Differential diagnosis: ulcers such as tuberculous ulcers, syphilis ulcers, soft chancre and epithelial cancer must be differentiated. It is easy to distinguish between ulcerative colitis and granulomatous colitis complicated by anal fissure.
Differentiation method
Anal fissures can have one or several fissures, but most fissures occur in the median line, anterior or posterior, i.e. at 6 or 12 o’clock of the truncus position. Due to the dryness of the stool, the skin of the anal canal is abraded when passing through the anus, which generally cannot be called an anal fissure. The wound is called anal fissure only when the anal canal is torn due to the hard and dry stool passing through the anal canal. The depth of the injury varies. In shallow fissures, only the skin of the anal canal is damaged, while in deeper cases, the subcutaneous tissue to the muscle tissue can be damaged, and even the muscle tissue can be damaged.
The difference between hemorrhoids and anal fissures
Most anal fissures are accompanied by sentinel hemorrhoids, especially in patients whose fissure condition has been neglected for a long time, and when it develops into an old anal fissure, it is often accompanied by both external and internal hemorrhoids, when both have basically the same appearance outside the anus. Therefore, it is beneficial to understand the difference between anal fissures and hemorrhoids and to raise awareness of anal abnormalities for treatment.
Anal fissures are characterized by fissures in the skin of the anal canal and ulcers in the anal canal that are difficult to heal. Hemorrhoids, on the other hand, are formed due to the formation of varicose veins and venous masses in the veins around the anus, as well as sliding mucous membranes in the lower rectum.
1. Anal fissures are dominated by pain and blood in the stool. Hemorrhoids are predominantly bleeding and are only painful if the external hemorrhoids are inflamed and swollen.
2. Anal fissures are visible as skin fissures in the anal canal, while hemorrhoids are not. This can be determined during anal fingering, but anal fissures are mostly not feasible for anal fingering, or speculum examination;
3. Anal fissures are often accompanied by anal papillomata or papillomas, while hemorrhoids are not accompanied by anal papillomata or papillomas;
4. In anal fissures, narrowing of the anal canal is seen, while in hemorrhoids, internal hemorrhoids are more often seen to be prolapsed and ectopic.
Anal fissure must be distinguished from the following diseases
Anal skin fissures: Mostly caused by anal pruritus, anal eczema, etc. The fissures are superficial and short, less than the anal canal, with light pain and little bleeding, heavy itching, and no complications such as ulcers, fissured hemorrhoids and enlarged anal papillae.
2.Anal tuberculosis: irregular ulcer pattern, subterranean edge, light pain, no fissured hemorrhoids, tuberculous nodules and caseous necrotic lesions can be seen during pathological examination.
3.Anal skin cancer: irregular ulcer pattern, uneven surface, elevated edges, hard texture, with strange odor and continuous pain, and cancer cells can be seen in pathological section.
[Treatment
Fresh anal fissure
Healing can be achieved through non-surgical treatment, such as local hot water sitz bath and potassium permanganate solution after stool, which can promote the relaxation of anal sphincter; the ulcer surface is coated with anti-inflammatory and pain-relieving ointment (containing dicaine, safranin, methotrexate, etc.) to promote ulcer healing; oral laxative is used to loosen and lubricate the stool; procaine can be used for severe pain and local closure or reserved enema to relax the sphincter.
Old anal fissure
If the above treatment is ineffective, surgical excision can be used, including the ulcer along with the skin flab (anterior sentinel hemorrhoid) together with excision, also can cut part of the external sphincter fibers, can reduce postoperative sphincter spasm, favorable healing, the wound is not sutured, postoperative to keep the bowel movement, hot water bath and wound dressing until completely healed.
There are several surgical treatment methods as follows.
1.Excision: applicable to stage III or chronic anal fissure, with good postoperative effect and very little recurrence.
2.Posterior internal sphincterotomy: The main purpose is to eliminate the spasm of the internal sphincter.
3.Lateral internal sphincterotomy: the main purpose is to reduce and prevent anal malfunction.
4.Anal canal dilatation: mainly used for the loss of elasticity and contraction of anal canal caused by various reasons, sphincter malfunction and occurrence of organic stenosis.
5.V-Y anal canalplasty: it is suitable for anal canal skin defect and anal fissure with obvious stenosis.
6.Perianal skin fissure treatment: the choice of surgery or not should be based on the etiological condition.
7.Anal fissure with stage I or small stage I internal hemorrhoid: lateral internal sphincterotomy should be done first, and then injection treatment of internal hemorrhoid after the anal fissure is cured.
Other therapies: such as laser, electrocautery treatment, etc.
Principles of treatment for anal fissure
The treatment principle of anal fissure is that acute anal fissure should be treated mainly by conservative therapy, i.e. non-surgical therapy, and it is desirable to stop pain and bleeding to prevent a vicious cycle of pain. For chronic anal fissures or stage III anal fissures, surgical treatment should be the main treatment to completely eliminate the causes of anal fissures and factors that aggravate pain.
(1) Keep the bowels open and prevent constipation: eat more vegetables and fruits, increase water intake and correct constipation. Oral laxatives or paraffin oil can be taken to loosen and lubricate the stool to facilitate defecation.
(2) local sitz bath: use hot water or potassium permanganate warm water sitz bath, temperature 40 ℃ ~ 50 ℃ (2 ~ 3 times a day, 20 ~ 30 minutes each time. Warm water bath can relax the anal sphincter, improve local blood circulation, promote the absorption of inflammation, reduce pain, and clean the local area to facilitate the healing of the wound. After the sitz bath, you can apply anti-inflammatory and pain-relieving drugs to reduce symptoms.
(3) Closure therapy: for severe pain, inject 1%-2% procaine into the base of the anal fissure and both sides of the anal sphincter to relieve the spasm of the sphincter to relieve pain.
(4) Anal canal dilation: for acute or chronic anal fissures without complications of papillary hypertrophy and anterior sentinel hemorrhoids. Dilation of the anal canal with fingers under local anesthesia or sacral anesthesia can release the spasm of the anal sphincter and achieve pain relief.
(5) Surgical treatment: For chronic anal fissures that do not heal for a long time and for which non-surgical treatment is ineffective, surgical treatment can be used.