Ebook Anorectal surgery: Part 2

Part 2 book “Anorectal aurgery” has contents: Functional anorectal disorders, anorectal malformations, fissure in ano, hemorrhoids, anorectal abscess, hidradenitis suppurativa, fistula in ano, pilonidal sinus, rectal prolapse, fecal incontinence.

Functional Anorectal

Disorders

A functional anorectal disorder is defined as “a variable combination

of chronic or recurrent anorectal symptoms not explained by structural or biochemical abnormalities”, or in simple terms,

“Anorectal symptoms, the etiology of which is currently unknown or

is related to the abnormal functioning of normally innervated and structurally intact muscles, or is attributed to psychological causes” Chronic anal or perianal pain without evident cause produces maximum mixed reactions among family, friends and physicians as compared to other disorders

Usually the result of common and easily recognized disorders such as:

Men and women of all ages are affected by anorectal disorders Their management is not limited to the evaluation and treatment

of hemorrhoids

The spectrum of anorectal disorders ranges from benign and irritating (pruritus ani) to potentially life-threatening (anorectal cancer) disorders

Patients usually present with ‘‘constipation’’, but the clinical picture of these disorders includes:

A combination of the following work-up helps arrive at the diagnosis:

• Though discomfort or pain is the predominant symptom; patients may also have dysfunctional voiding or defecation

• Associated findings frequently include impaired quality of life, anxiety, and depression

• Though it is presumed that visceral hypersensitivity and pelvic floor dysfunction may play a role, pathophysiology is not properly studied and poorly understood

• Because therapeutic approaches have not been rigorous, therapy is guided by clinical features

Levator Ani Syndrome

Irrespective of the fact that several syndromes have been described, the most common question in the mind of a colorectal surgeon is: What is the cause of this idiopathic perianal pain and how can it be relieved?

The first reference to anal pain appeared in 1859 when a syndrome called “Coccygodynia” was described

Ever since a number of different terms have been used, adding to confusion as to the definition of this syndrome

Coccygodynia is said to consist of a:

• Vague tenderness or ache in the region of the sacrum and coccyx

It was later suggested to the use of the term ‘levator syndrome’, and treatment in form of digital massage of the pelvic floor musculature was offered.

Around one-fourth patients suffering from this symptom consult

a physician, yet it is presumed that the associated disability is significant

More than half of affected patients are aged 30 to 60 years and prevalence tends to decline after age 45

Pathophysiology

Though the exact etiology is unknown different studies have suggested Different hypothesis for the pathology of levator ani syndrome, some of which are as mentioned:

• That levator ani syndrome results from spastic or overly contracted pelvic floor muscles

• That levator ani syndrome is associated with psychological stress, tension, and anxiety

• It is unclear if the association between chronic pelvic pain and psychosocial distress on multiple domains (e.g depression and anxiety, somatization, and obsessive-compulsive behavior) reflects an underlying cause or an effect of pain

• That levator ani syndrome may be due to visceral hyperalgesia

or increased pelvic floor muscle tension, supported by the fact that there is tenderness to palpation of pelvic floor muscles in chronic pelvic pain and levator ani syndrome

• That levator ani syndrome patients may have increased anal pressures or electromyogram activity Higher anal pressures may reflect increased external or internal anal sphincter tone

• Inability to relax pelvic floor muscles suggests pelvic floor dysfunction

Diagnostic Criteria

If the patient complains of atleast 12 weeks consecutively in previous

12 months for the following:

1 Chronic or recurrent rectal pain or aching and discomfort

2 Episodes last 20 minutes or longer

3 Other causes of rectal pain such as ischemia, inflammatory bowel disease cryptitis, intramuscular abscess, fissure hemorrhoids, prostatitis, and solitary rectal ulcer have been excluded, then the patient can be labeled as suffering from levator ani syndrome

Clinical Evaluation

The diagnosis of levator ani syndrome is based on symptoms alone.One important sign which can raise the diagnosis is:

• Posterior traction on the puborectalis revealing tight levator ani muscles and tenderness or pain

• Tenderness usually may be predominantly left-sided

• Massage of this muscle will generally elicit the characteristic discomfort

Depending on the above-mentioned sign and symptom complex the syndrome has been classified into two levels:

• A “highly likely” diagnosis of levator ani syndrome if symptom criteria are satisfied and these physical signs are present, or

• A “possible” diagnosis if the symptom criteria are met but the physical signs are absent

To exclude alternative diseases, clinical evaluation will usually include sigmoidoscopy and appropriate imaging studies such as defecography, ultrasound, or pelvic CT.

In situations where it becomes essential to offer treatment

it would be wise to select a modality like biofeedback which has

no significant adverse effects and prevent further harm to the patient

Many patients fail to respond to treatment Yet surgery should be avoided

Proctalgia Fugax

Proctalgia fugax is an enigmatic disorder Proctalgia fugax is a condition characterized by recurring attacks of pain deeply inside the rectum

Described in 1935, proctalgia fugax as against levator ani syn- drome, is a relatively well-defined syndrome of obscure causation Ever since it was named in 1935, in an article entitled “Proctalgia fugax: a little known form of pain in the rectum”—It has been a source of controversy

The majority of observations that were made then in 1935, in the article mentioned hold true today

Proctalgia fugax is described as sudden, severe, irregular attacks

of rectal pain lasting several seconds or minutes followed by complete resolution without any untoward effects

Proctalgia fugax has also been defined as recurring attacks of distressing rectal pain with no local positive findings in the rectum Attacks are infrequent, occurring less than five times a year in more than half of the patients

Pathophysiology

The etiology remains unknown, however most theories are focused

on spasm of the levator ani muscle and sigmoid colon, where as some studies suggest that smooth muscle spasm may be the cause

of proctalgia fugax

It has certain features which suggest that it is due to a sustained muscle spasm

Because of the short duration and sporadic, infrequent nature of this disorder, the identification of physiological mechanisms of this disorder is difficult

Many patients on psychological testing have been found to be perfectionistic, anxious, and/or hypochondriacal

It is commoner in men than women, though prevalence rates may vary in men and women

Beginning in early adult life and the symptoms cease spontaneously in late middle life

The ages of the patients varies between 18 and 65 years Estimated prevalence ranges from 8 to 18% However only 17 to 20% of those affected report the symptoms to their physicians

Yet a curiously large number of reports have concerned doctors

Attacks may occur on several consecutive nights, during periods

to account for it

In its most common form the disease starts with nocturnal attacks of pain Other ways of onset are less common and the patients ultimately develop the nocturnal attacks

Particularly common at night it can occur at any time

It begins suddenly and progresses to a cramp-like pain which may be very severe, but which usually resolves after less than 30 minutes

The pain is felt at a constant site above the level of the external anal sphincter in the anal canal or rectum

A feature which suggests that it may be due to a cramp-like spasm

of the muscles of the pelvic floor is that the pain may sometimes

be relieved by flexing the extended legs as far as possible onto the abdominal wall, as when sitting on the floor

There is a high incidence of symptoms of irritable bowel syndrome in patients with proctalgia fugax However, the pain itself

is not accompanied by an acute bowel disturbance

Specific description of pain like “gnawing, aching, cramp-like, or stabbing” has been reported by some patients

But there are many more vivid accounts:

be necessary

Clinical Evaluation

Diagnosis is based on symptoms alone There are no physical examination findings or laboratory tests that support the diagnosis Examination reveals that the perineum descends below the plane of the ischial tuberosities at rest, or during straining in patients suffering from the descending perineum syndrome

Other endoscopic and imaging modalities are used to exclude other underlying disorders

Treatment

The real difficulty in treating proctalgia lies in preventing attacks This is practically impossible and all efforts directed towards this end have failed so far

Treatment for most patients consists only of reassurance and explanation, because episodes of pain are very brief

Before referral most of the patients have been treated without success

Various treatments including tricyclic antidepressants, diazepines, phenothiazines, paracetamol, codeine, dihydro-codeine, and stronger narcotic analgesics are offered to patients

Others have recommended clonidine or amylnitrate

However, a small group of patients who have proctalgia fugax

on a frequent basis: Have shown improvement and reduction in the duration of episodes of proctalgia with inhalation of salbutamol (a beta adrenergic agonist)

Local measures such as local anesthetic creams, and surgical approaches such as maximal anal stretch procedures, removal of anal mucosal tags, hemorrhoidectomy or pelvic floor repair, were also unsuccessful

In most cases, in patients considered to be suffering from pain of psychogenic origin, if subjected to psychiatric evaluation,

no abnormality other than that attributed to the effect of chronic unrelieved pain is usually found

It is difficult to devise appropriate treatment because the exact pathophysiology is unknown

Percutaneous vibration has been used without effect in some patients

Pudendal nerve block relieved the pain on the treated side for a few hours only and that too in small number of patients

Similarly, carbamazepine is also ineffective or only partially effective

Treatment thus remains unsatisfactory Massage of the pelvic floor musculature was uniformly ineffective

The patient should avoid the kind of food or drug that, in his experience, precipitates the pain

The belief that Proctalgia fugax is a visceral neurosis is supported

by the fact that a number of variety of the measures have been devised by the patient and have given good relief in good number

self-of patients

Though in any complaint which is naturally self-resolving and

of short duration, it is admitted that this is a common enough happening

Most patients learn from their own experience some maneuver which seems to help them relieve the symptoms

• Similarly the discharge of any particulate fecal material, even

in small amounts; may relieve pain in some patients

• It is likely that each effort only signals the relaxation of muscle spasm and the end of an attack

Fig 12.1: Genupectoral position

In some instances, the effort of ineffectual straining may only intensify and prolong the spasm because the patient can expel nothing at all from the rectum

Once the attack is impending, postural treatment is considered the most effective The genupectoral position can be adopted (Fig 12.1)

Or the patient is advised to lie down on the right side with the buttocks slightly elevated on a pillow, and this should be supplemented

by firm pressure on the anus using the left hand for that purpose This may help abort or greatly alleviate a severe attack

It can be relieved most effectively by the immediate taking of food or drink The mechanism presumed behind this is that the initiation of the gastrocolic reflex inhibits the painful muscle spasm Most of the other lines of treatment like the ones mentioned below are largely impracticable:

• The passing of a rectal catheter, or even

• The giving of a small enema, warm or cold, water or oil, or even air alone

It seems likely that any success in such maneuvers results from engaging the attention and by arousing interest, curiosity, or expectation

Use of Clonidine for Proctalgia Fugax

Clonidine works by stimulation of alpha receptors which in turn:

• Produce relaxation of the rectal smooth muscle (effect on para sympathetic neurones)

• Relaxation of internal anal sphincter (effect on sympathetic neurones)

The antispastic effect of clonidine might possibly inhibit the spasm of levator ani and external anal sphincter

Apart from this, the central sedative and analgesic actions of clonidine also appear to be very useful in producing relief

Clonidine though needs more evaluation, appears to be effective

in treatment of proctalgia fugax

Perineal Descent Syndrome

Perineal descent was first described by Parks et al in 1966

It was assumed to be the final outcome of a cycle that included regularly straining with bowel movements which in turn caused the anterior rectal wall to balloon into the anal canal

The hypothetical sequence of events have been documented as follows:

• Patients usually have a complain of a feeling of inadequate evacuation of stool

Pathogenesis

Perineal descent syndrome has usually been attributed to:

• Pelvic floor weakness resulting from

– Neuropathy

– Trauma during:

- Pregnancy or

- Childbirth

– Abnormal defecation behaviors

However, the claims that there is relation between increased perineal descent and pudendal neuropathy have been proved otherwise

With increasing number of vaginal deliveries, a prolonged terminal motor latency is seen yet no association between perineal descent and pudendal neuropathy has been demonstrated in these patients

Individuals with descending perineal syndrome present with:– Constipation in the early phase

Pruritus Ani

Pruritus ani is defined as intense chronic itching affecting perianal skin Characterized by intense itching around the anus pruritus ani, is

a troublesome symptom that is associated with most forms of anal disease, but in some patients with this symptom no etiological anal disease may be found

As good number of patients suffer prolonged intractable symptoms and treatment is often unsuccessful It is a frustrating condition for both patients and clinicians

Actually the symptoms of itching or irritation of the perianal skin are usually a disorder of mixed etiology:

Even though the dermatological conditions are usually not restricted to the perianal area, the morphology of perianal skin lesions may be atypical for the disease elsewhere

Paradoxically in most patients the problem is due either:

As against the fact that nearly 100 different causes for pruritus ani have been reported, most patients with pruritus ani do not have

a discernible cause for their condition, pruritus ani is classified as idiopathic when no cause can be found

Though but not conclusively proved to be of relevance the following factors play an important role in the etiopathology of pruritus ani:

Hygiene: Perineal fecal contamination: Fecal contamination causing

pruritus ani is because of prolonged contact with a moist substance

or a hygiene issue

Small particles of feces accumulate on the perianal skin, in presence of any condition that hampers efficient wiping of the anus and these accumulated particles act as an irritant

Fecal contamination or soiling may be overt or occult The patients with occult soiling are unaware of the same yet the soiling

is good enough to initiate itch and scratching

Clothing: Excessive sweating exacerbated by poorly fitting

undergarments and poor personal hygiene are also implicated

Quality of perianal skin: Perianal skin also reacts differently from

skin elsewhere, skin-patch testing using autologous feces have produced anal symptoms in up to one-third of patients with pruritus ani and around fifty percent plus of asymptomatic individuals, where as only four percent of cases have been reported to develop irritation with a fecal patch test on the arm

Occuring within six hours, the itching usually gets relieved by washing suggesting irritation as the cause rather than an allergy Any factor which increases occult or overt soiling augments exposure of the perianal skin to irritants and is a potential area of therapy

Quality of stool: Stool consistency and mucous seepage are

attributed as etiological factors

• Occult or overt soiling

The following two causes have been documented:

– Anal sphincter relaxation in reaction to rectal distension

– Coffee by lowering the anal resting pressures

Accidently during anorectal physiology testing exaggerated rectoanal inhibitory reflexes and incontinence are found in patients with pruritus ani

A primary or postsurgical problem: Altered anal morphology may lead to fecal soiling

Inability to evacuate their anal canals completely in these individuals results into the retained fecal material to escape later and further with result in itching

Patients with pruritus ani are less able to maintain absolute continence when dealing with:

• Candida albicans in diabetic individuals

Candida infection may occur via a colonized partner and

they too may need therapy

• Threadworms are known to infect multiple family members

• Perianal viral infections: There is no evidence for their causative role

in idiopathic pruritus ani, even though they commonly cause itch

• Sexually transmitted bacterial infections

• β-Hemolytic streptococci, Staphylococcus aureus and Coryne­

bacterium minutissimum infection can lead to itch that lasts long,

β-Hemolytic streptococci mostly occurs in children and presents

– Sensitization by chemicals found in the following is the basic cause:

For this reason, patients should avoid contact with the irritant and soap

Foods

Some form of the following foods have been implicated in idiopathic pruritus ani, the supporting fact being relief in itch of pruritus ani after some days of avoidance of these foods, these foods have also been shown to have a quantity based effect as acceptable levels can

be calculated by gradual reintroduction:

Retrospective studies have shown one of the following as mechanisms by which foods are thought to cause itch:

– Anal trauma from recurrent wiping

Colorectal and Anal Disease

Most coexisting anal conditions have been found to precipitate or exacerbate itch

More than half of the patients with pruritus ani have anorectal disease

The most common anorectal condition being hemorrhoids Functional bowel disorders may contribute and hemorrhoids may add to sphincter dysfunction and fecal seepage

Literature shows that around one quarter of patients with proctological disease and pruritus ani have by anal or colorectal cancer as the primary pathology

Treatment of all colorectal and anal conditions in these patients have shown some excellent results

Anal surgery contributed to the elimination of perianal fungal infection and together reduced pruritus

Dermatological Conditions and Neoplasia

• Psoriasis: In 5 to 55% of patients with pruritus ani, psoriasis has

been found

• Perianal plaques: Isolated perianal plaques may not be very

characteristic, the reason being they are altered by repeated scratching, but they can occur and have a sharp edge

• Lichen sclerosus: Perianal skin is white, atrophic, and wrinkled in

lichen sclerosis and has typical biopsy features

• Paget’s disease: More than half of patients have associated itch.

• Bowen’s disease: Same as in paget’s disease, more than half

of patients have associated itch, the skin lesions in both these conditions have well-defined limits

• Other skin cancers present with pain and bleeding

Steroid-Induced and other Medications

Because potent topical steroids can cause: Thinned skin, acute dermatitis and contact dermatitis from sensitization, they are used sparingly

Addiction of topical steroids has been described in patient who use it frequently to control the rebound itch after cessation

Some medications ingested orally, such as:

Biological enzyme based detergents should be avoided as these may result in itch by the residue that remains after the use.

Systemic Disease and Psychological Factors

Directly or indirectly in combination any of the following illness can lead to pruritus ani, and the most common are:

Symptoms may be the sole focus of attention, and are usually worse at night

Because of excessive sweating the condition is worse during the summer

Scratching the perineum, produces short lived relief and relieves the patient of the itch But continued scratching causes damaging excoriations, which may bleed

This vicious circle of itching and scratching is difficult to break and may induce a state of nervous exhaustion

Examination of the perineum discloses a wide range of appearances

Some patients with severe pruritus ani have:

Considered safe, devoid of side effects and not as a medicine a good number of over-the-counter topical therapies may have been the causative factor for the symptoms or altered skin morphology History of previous patch testing, illness, diarrhea and treatments such as antibiotics and steroids may guide to the diagnosis

Intermittent or seasonal itch is very typical of recurrent anorectal pathology, different clothes or laundry detergents

Examination

The patient should be examined for evidence of other dermatological disorders

Complete and general examination may reveal other sites of localized or generalized skin disease or infection

• Tinea, psoriasis or neoplasia have a distinct boundary

However the extent of neoplasia extends beyond this sharp border

If the reddened skin has a clearly demarcated margin fungal infection should be strongly suspected The diagnosis is further confirmed by microscopic examination of skin scrapings:

• Erythema is seen with chronic topical steroid use

• Bright erythema suggests yeast infection

• Hyperpigmentation is evidently present in any chronic inflammation, in these cases infection and chronic discharge should be looked for

• The labia or perineum are always involved in lichen sclerosus

• Herpes is associated with severe itch and multiple lesions

• Severe cases have the following characteristic symptoms:– The skin becomes lichenified

– Sexually transmitted infections

– Idiopathic inflammation is nonspecific visually and is identified by indistinct borders

• Chronic trauma results in lichen simplex chronicus

• Threadworms appear as thin white threads about 6 mm in length and may be seen around the anal orifice, they can also be identified in the effluent of a diagnostic saline enema

• A thorough anorectal examination is performed to identify potentially treatable causes of pruritus ani

Investigations

Because microbiological investigations are frequently incorrectly performed, false negatives occur, even though the concurrent rate

of infection is significant; this is the reason for treatment failure in these type of patients

Special instructions for media and preservation of specimens:

• Fungal and bacterial specimens should be placed in bacterial transport medium and refrigerated

• Anaerobic samples can be stored at room temperature but need specific anaerobic medium

• Exudates from vesicles should be placed on a slide or viral culture medium, after vesicles have been unroofed

Apart from the affected skin, neighboring normal skin should be included in all biopsies

Skin-patch testing should be carried out, in all refractory and persistent cases

Management

Treat the Cause is the Thumb Rule

However, most patients will not have an identifiable lesion to treat, and many of the patients who undergo surgery for potentially implicated anorectal conditions continue to have symptoms

Patients tend to make repeated visits to outpatient clinics with little improvement, seeing a different doctor at each visit

Guidelines for patients with pruritus ani

Guidelines on how to minimize the symptoms need to be provide

to these patients with refractory disease

As a matter of fact strict adherence to such advice undoubtedly helps and the regimen may be relaxed as symptoms ease

Management has three components which function in parallel:

• Certain foods

• Drinks

The perineum should be rinsed free of residue with a shower head,

if a shampoo or any other cleanser is used whilst in the bath

Patient should be provided with a list of foods that have been found to be associated with itching

An elimination diet may be attempted and symptom diary kept

Clothes should be washed in nonperfumed detergent

If itch worsens after the use of wet wipes, patients must be warned against their use and they must be stopped immediately in case of sensitization

General Control Measures

The perineum needs to be washed with a shower head without soap, and dried with a hair dryer

To assure that the anal canal is washed of retained feces Perineal cleansing should ideally be done in the squatting positions

Instead of soap aqueous cream or emollients should be used Barrier creams, such as zinc oxide or petroleum ointment can be applied after washing

Before underwear is worn The perineum should be absolutely dry and the underwear should be changed daily

Especially for nocturnal itch, acute itch is suggestive of fecal seepage and immediate cleansing is the most effective remedy

Patients should be given advice on how to cleanse when outside their homes

Small containers of oil-based preparations or aqueous cream tubes take up little space and the contents can be squeezed onto cotton wool to clean the perineum

In those who sweat excessively, cotton tissue can be placed perianally to absorb moisture

To reduce trauma from inadvertent nocturnal scratching, short finger nails have been advocated

Active Treatment

If threadworms are discovered:

• Patients and their families are treated with a course of mebendazole

• To prevent reinfection, strict measures of hygiene need to be adopted

Pediculosis pubis and scabies are treated with topical lindane or malathion

If the diagnosis is confirmed as fungal infection, treatment with a topical antifungal agent is given

All dermatophyte infections should be treated in all with a topical imidazole or terbinafine

Treat Candida infection with nystatin ointment.

Many may become obsessional about their bowel habit and perineum because they continue to suffer

The vicious circle of itching and scratching can be broken by local applications Calamine lotion and carbolic lotion are the most popular topical preparations used to soothe the perineum

Though some doctors advocate injecting alcohol or phenol into the perianal skin in order to destroy the subcutaneous nerves and ease the itching, the results, however, are almost invariably disappointing Dermatological conditions should be treated by an appropriate specialist as for example in chronic cases a skin condition such as psoriasis should not be missed and a dermatological opinion is valuable

β-Hemolytic streptococci, S aureus and C Minutissimum should

be eliminated with topical antibiotics such as fusidic acid or mupirocin, and oral antibiotics may be necessary especially if:

Nocturnal scratching which is probably a marker of anal seepage can be reduced by systemic antihistamines and, the patient should

be advised to wash the area immediately and apply a barrier cream Topical antihistamines are not potent enough and sensitize the skin

The short, intense, burning sensation produced by topical capsaicin produces an inhibitory feedback which may eliminate to need to scratch

Anal tattooing should be considered:

– Not only to reduce the expectation of immediate cure

– But also to improve compliance with advice given

• Warn the patient that a precise cause for their condition may not

be found but that

• By paying attention to personal hygiene their symptoms can be minimized

Solitary Rectal Ulcer Syndrome

Solitary rectal ulcer syndrome (SRUS) and stercoral ulceration, are two conditions that are related to local tissue ischemia and often seen in the elderly population though it can affect all ages

Solitary rectal ulcer syndrome is the final clinical outcome of different pathologic settings associated with compromised perfusion

to the rectal mucosa

Solitary rectal ulcer syndrome, as the name implies, consists of several different clinical pathologic processes, which ultimately end in a mutual common pathway that is associated with reduced blood perfusion of the rectal mucosa, leading to local ischemia and ulceration

Solitary rectal ulcer syndrome is a benign uncommon disorder of evacuation frequently associated with rectal prolapse, but most of the times it is a disabling condition in which excessive straining at defecation results in focal mucosal changes with pain, bleeding, and mucous discharge

In the early nineteenth century, by the French anatomist J Cruvilhier, in his report on chronic rectal ulcer described the SRUS

In 1969, by Madigan and Morson, the distinctive histopathologic characteristics were defined

With a prevalence of less than 1 in 100,000 per year, SRUS is a rare syndrome

Clinical Presentation

Solitary rectal ulcer syndrome (SRUS) diagnosis is delayed in many cases due to:

• Excessive straining during defecation

• A behavioral disorder

Although the gradual sequence of this pathology may originate for various reasons, SRUS has been related to several independent clinical settings:

• Occult or overt rectal prolapse with paradoxical contraction of the pelvic floor

• Straining during defecation results in prolapse and high fecal voiding pressures which in turn reduce local blood flow causing ischemia and ulceration

• The pressure of prolapsed mucosa against a closed anal canal can result into mucosal trauma

Rectal Prolapse and Intussusception

Rectal intussusceptions leads to:

• Full-thickness rectal prolapse

• Which in turn leads to localized vascular trauma and ischemia

• Initiates solitary local ulceration

Paradoxic Contraction of the Pelvic Floor Muscles

Uncoordinated sequence of muscle contraction and relaxation that is required for the defecation process, and also known as puborectalis syndrome or pelvic outlet obstruction

It typically causes increased pressure inside the rectum and anal canal, generating ischemia and ulceration:

• Evidence of inappropriate pelvic floor contraction is seen in electromyographic and video proctographic studies

Chronic constipation and hard stool leading to extraneous defecation basically cause high pressure similar to pathogenesis of outlet obstruction and lead to:

• Chronically reduced mucosal blood flow in the rectum

• Local mechanical-induced tears

Radiotherapy and Ergotamine Suppositories

The use of ergotamine suppositories has been shown to have a substantial role in the pathogenesis of SRUS

Again, ergotamine suppositories have been shown to effect the mucosal perfusion and results in ischemia

These strong vasoconstrictors, indicated for treating severe migraine, have been shown to induce local ischemia and ulceration Radiotherapy, which in the long-term affects permanently small blood vessels, has been cited as potentially antecedent to SRUS as well

• The mucosa of the anterior wall of the rectum, 7 to 10 cm above the anal verge, is the most common area of prolapse into the anal canal, and this corresponds to the usual location of ulceration in SRUS

• SRUS has been associated with use of ergotamine suppositories and after radiation therapy, further supporting a pathogenic role for ischemia

• Moreover, the successful treatment of SRUS using biofeedback has been associated with an increase in local blood flow, additionally suggesting that SRUS may be associated with reduced rectal blood flow from impaired extrinsic autonomic cholinergic nerve activity

Treatment

The therapeutic approach is variable, because the etiology of SRUS

is diverse

The therapeutic outcomes varies depending on the underlying cause and the chosen treatment

Usually by direct endoscopy and pathology results from biopsies that ruled out malignancy the diagnosis is arrived at, detecting the underlying pathologic basis of disease is the next diagnostic step Thorough history-taking: To rule out:

• Local trauma or

• Behavioral patterns and

– How to avoid these may be the initial treatment

The following imaging and physiologic studies are usually indicated and help diagnose muscle relaxation-related pathologies as well as other mechanical disorders:

• Rectal ultrasound

The therapeutic aspects should focus on biofeedback training sessions, educating the patient to control the proper muscle contraction and muscle relaxation sequence, when the source of local ischemia is pelvic outlet obstruction Surgical intervention is indicated, in some cases when rectal prolapse is diagnosed

Equally important is the decision on choosing the correct surgery, which may vary from a resection using the perineal approach to abdominal operation or even a permanent colostomy, should be made independently for each patient

Exclusion of malignancy is essential Local treatments with steroid

or sulfasalazine enemas are not effective in all patients, whereas using a fibrin sealant achieved good results in some patients Identifying the correct foundation allows proper treatment with optimal results

Anorectal Malformations

The surgical correction of anorectal malformations remains a serious and unresolved problem, despite its relatively frequent occurrence

It is important to consider the importance of the sphincter complex, in understanding the spectrum of anorectal anomalies This complex is the combination of the:

Division of the abnormalities into high (rectal) malformations and into low (anal) malformations has proved to have both therapeutic and prognostic significance

The incidence is 1/4,000 live births

Significant long-term concerns focus on bowel control and urinary and sexual functions

During the last several decades, significant advances have been made in the understanding and treatment as well as in the correction

of anorectal malformations

Despite these advances, the primary goal of the surgeon remains

a very evasive one

The main aim of the surgical treatment for these patients is to achieve a repair and to create a reconstructed anatomy which provides a nearly normal anal outlet for the patient, in an attempt to provide these children with a good quality of life

Imperforate Anus

The first description of imperforate anus was by Aristotle, who described the condition of an imperforate anus with a rectourethral fistula in a cow

Paul of Aegina, a Byzantine physician, successfully incised the perineum of an infant born without an anus, in the seventh century

In 1835, Jean Zulema Amussat described the dissection of the perineum with mobilization of the end of the rectum to the skin, emphasizing the necessity of mucosal continuity with the skin

Prevalance

The incidence of occurence of imperforate anus is 1 out of every

4000 to 5000 live births, most commonly with:

• A rectourethral fistula in boys

• A rectovestibular fistula in girls

Imperforate anus with a rectovaginal fistula was considered

as a relatively common defect in earlier times, later retrospective studies have shown that these malformations were likely either:

Imperforate anus in good number of cases is a misnomer, because the great majority of cases have some opening even though it be displaced and small

The majority of abnormalities found clinically can be explained

by these two concepts:

• Failure of migration so that an orifice or its remnant will remain at the site of a more primitive anus

• The concept of excessive fusion of the lateral genital folds

‘covering ‘the anus and usually leaving an opening somewhere anterior to the usual anal site

Clinically imperforate anus can be divided into:

• Low lesions where the rectum has descended through the sphincter complex

• High lesions where it has not

Most patients with imperforate anus have a fistula

In both males and females there is a spectrum of malformation

Manifestation and Diagnosis

Low Lesions (Fig 13.1A)

As a protocol examination of a newborn includes the inspection of the perineum

Further evaluation is needed in the absence of an anal orifice in the correct position

Many patients have no symptoms, although the primary symptoms and constipation, have been attributed to anterior ectopic anus

Commonly known as anal stenosis or anterior ectopic anus, mild forms of imperforate anus are probably imperforate anus with a perineal fistula

The normal position of the anus on the perineum is ximately halfway between the coccyx and the scrotum or introitus There may be a low lesion or “covered anus”, even if no anus or fistula is visible

In these cases:

• The buttocks are well formed

• Often presence of a thickened raphe or “bucket handle” (also called “black ribbon.”)

Meconium bulging may be seen after 24 hour, due to accumulation and presents as a blue or black bulge

An immediate perineal procedure can often be performed in these cases, and then followed by a dilation program

In a male patient: The perineal cutaneous fistula may track

anteriorly along:

• The median raphe across the scrotum

• Sometimes down the penile shaft

In males, low lesions usually present with:

• Meconium staining somewhere on the perineum along the median raphe

In most cases the perineal fistula is a thin track, and the normal rectum lies just a few mm from the skin

Some of these patients have accompanying extraintestinal anomalies

Figs 13.1A to D: Imperforate anus in females

Girls with low lesions also present as a spectrum:

• From an anus that is only slightly anterior on the perineal body

• To a fourchette fistula that opens on the moist mucosa of the introitus distal to the hymen

In the latter instance the rectum descends through the sphincter complex

The primary treatment of children with a low lesion is perineal procedure and dilation

It is very important to visualize these fistulas for proper evaluation and treatment to the extent that is advised not to pass a nasogastric tube for the 1st 24 hours, in order to allow the

Figs 13.2A to C: Imperforate anus in males

abdomen and bowel to distend, in turn pushing meconium down into the distal rectum.

High Lesions (Figs 13.1B and 13.2A to C)

A high imperforate anus in a male has no apparent cutaneous opening or fistula but usually has a fistula to the urinary tract, either the urethra or the bladder

The perineum appears flat in a boy with a high imperforate anus High imperforate anus is usually accompanied by a fistula, the features of different fistula are as follows:

When the fistula is high, entering:

• The bulbar or prostatic urethra or the bladder air or meconium may be passed via the penile urethra

Most commonly in males a rectourethral fistula features:

In Boys with Trisomy

Apart from all the features of a high lesion:

• There is an absence of a fistula