Hemorrhoids

INTRODUCTION

The term hemorrhoid was coined by Hippocrates and is derived from the Greek words haema meaning blood and rhoos meaning flowing.  Hemorrhoids are bundles or cushions of tissue within the anal canal, which contain primarily blood vessels surrounded by connective tissue and muscle fibers.  They lie just below the outer layer or epithelium of the anal canal in what is termed the submucosal layer and are mainly found in three positions: left lateral, right anterior, and right posterior.  Despite what is commonly believed, hemorrhoids are actually normal structures.  They help protect the anal canal during defecation by engorging with blood, thereby providing cushioning against hard stool.  They are also thought to play a role in continence to gas and stool by contributing to resting anal pressure.  It is when these vascular cushions become enlarged and bulging that they are officially termed “hemorrhoids” and may become problematic.  In fact, hemorrhoids are often thought of as “varicose veins” of the rectum and anus.

PREVALENCE

Symptomatic hemorrhoids are reported to occur in approximately 4-5% of the population.  However, this may be an underestimation, as many people are reluctant to seek medical care for hemorrhoids out of fear or embarrassment.  Hemorrhoids affect men and women equally, and occur most frequently in the 4^th, 5^th, and 6^th decades of life. 

PATHOPHYSIOLOGY AND ETIOLOGY

The functional changes that accompany hemorrhoid formation are not clearly defined.  Most people assume that hemorrhoids represent abnormally dilated veins, or artery to vein connections with prolapse or slipping down of the connective tissue surrounding these vessels.  Shear forces that accompany straining and defecation, weakening of the tissues themselves, and abnormally high resting anal pressures are all thought to play a role in the tissue dilation and prolapse associated with hemorrhoids.  Although the exact etiology of hemorrhoids is unknown, several conditions, which relate to the issues discussed above, have been implicated in their development.  These include aging, chronic constipation or diarrhea, excessive straining with bowel movements, inadequate fiber intake, laxative or enema overuse, prolonged lavatory sitting, pregnancy, ascites, and pelvic masses.  Heredity is also suggested to contribute to hemorrhoid formation.

CLASSIFICATION

Hemorrhoids are classified according to their relationship to the dentate line, an anatomic partition between the rectum and anus (Figure 1).  External hemorrhoids originate below the dentate line and are covered by squamous epithelium, a lining richly innervated with pain fibers.  Internal hemorrhoids originate above the dentate line and are covered by mucosa, which is largely devoid of pain fibers.  Hemorrhoids can sometimes be mixed or internal-external.  Internal hemorrhoids are further divided into four categories based on their degree of prolapse:

• First degree hemorrhoids protrude into the lumen of the anal canal and cause bleeding, but they do not prolapse beyond the external sphincter (the distal-most portion of the anal canal).
• Hemorrhoids that spontaneously prolapse and reduce, particularly with defecation, are second degree hemorrhoids. 
• Third degree hemorrhoids prolapse beyond the external sphincter and require manual reduction to return to normal position within the anal canal. 
• Fourth degree hemorrhoids are prolapsed and cannot be reduced.  

EVALUATION AND DIAGNOSIS

The most common presentation of hemorrhoids is painless bleeding of bright red blood with bowel movements.  Other symptoms include pain or discomfort, itching, swelling, prolapse, and discharge or soiling.  Acutely painful, sometimes bleeding masses are likely thrombosed external hemorrhoids (hemorrhoids which contain clotted off blood) or incarcerated and gangrenous internal hemorrhoids, both of which may require surgical treatment.  Symptoms of hemorrhoidal disease are often aggravated by constipation or diarrhea.   

When evaluating a patient with hemorrhoids, doctors must consider other causes of rectal bleeding, masses or pain such as colorectal cancer, inflammatory bowel disease, rectal prolapse, anal warts, anal fissures, perianal skin diseases and perianal abscesses or fistulae.  As well as by history, the diagnosis of hemorrhoids is made by physical examination, ideally with anoscopy (visualization of the anal canal using a lighted tube).   Physical examinations include inspection of the perianal area for lumps or dark areas consistent with external hemorrhoids.  Physicians may ask patients to strain, particularly in the sitting position, in order to elicit prolapsing of internal hemorrhoids.  Internal hemorrhoids cannot otherwise be palpated on digital exam.  Additional studies such as colonoscopy or contrast enema may be necessary to exclude alternative diagnoses.

TREATMENT

Non-invasive Therapy

An important component of hemorrhoid treatment is prevention.  Avoiding excessive straining, such as with constipation, helps to thwart the formation of hemorrhoids.  Increasing daily fiber and fluid intake softens stool.  The recommended daily fiber intake is 20-30 grams, compared with the 15 grams a day the average American consumes.  Foods high in fiber include fresh fruits and vegetables, legumes, whole grains, and cereals.  Multiple fiber supplements, often containing either psyllium or methylcellulose, are available as well.  Fiber supplementation not only plays a role in hemorrhoid prevention, but also in their therapy.  A high fiber diet has been shown to decrease the bleeding and perhaps also the pain and prolapse associated with hemorrhoids.

Noninvasive hemorrhoid therapy generally provides symptomatic relief from, rather than a definitive “cure” for hemorrhoids.  The use of topical agents does not affect the incidence of hemorrhoidal bleeding or prolapse.  Instead, these medications target the itching, burning, irritation, and swelling associated with hemorrhoids.  Topical agents may contain local anesthetics, analgesics, anti-inflammatory substances such as steroids, medicines that constrict and shrink blood vessels, barrier substances, and astringents.  They are available in several different formulations including pads, creams, ointments, lotions, gels, and suppositories and are mostly sold over-the-counter.  In Europe and Asia, hydroxyethylrutoside, an oral compound derived from citrus plants, is sometimes used to treat hemorrhoids.  Although exactly how this medication works is unclear, it is known to increase elasticity and permeability of blood vessels as well as enhance lymphatic drainage.  At present, this medication is not approved for use in the United States.  The application of topical agents, particularly those containing steroids, should be limited to one week, as their prolonged use predisposes to negative side effects such as dermatitis or tissue thinning.  Sitz baths (10-15 minute warm water or saline soaks) may also help alleviate hemorrhoid itching and burning as well as improve overall anal hygiene.
 

Thrombosed External Hemorrhoids

Thrombosed external hemorrhoids usually manifest as acutely painful masses.  Heavy lifting, excessive straining, and prolonged sitting can all precipitate their formation.  Although they are often managed successfully with stool softeners, oral and topical analgesics and sitz baths, surgical evacuation is sometimes needed to provide adequate and expedient pain relief.  Medications that relax the anal sphincter muscles (e.g., Nitroglycerin and Nifedipine) may also help reduce pain.  Pain from thrombosed hemorrhoids generally subsides after 2-3 days.  Thus, surgical management should only be considered within about 48-72 hours of pain onset.  Surgery consists of an incision around the thrombosed hemorrhoid and clot removal.  It is generally performed in the outpatient setting with local anesthesia.  The main complications of surgery are bleeding and scarring.  Infection can also occur, but is extremely uncommon.  Other than in cases of thrombosis, external hemorrhoids rarely require invasive therapy. 

Thrombosed Internal Hemorrhoids

Though relatively uncommon, 3^rd and 4^th degree hemorrhoids can also become thrombosed.  This is because hemorrhoids in the prolapsed position are prone to diminished blood flow or “stasis.”  It is important to differentiate between thrombosed internal and thrombosed external hemorrhoids because internal hemorrhoids more often require surgery due to failure to resolve after conservative measures.  Further, the surgical management of thrombosed internal hemorrhoids is complicated due to their interior position.  Formal hemorrhoid excision, or “hemorrhoidectomy,” is usually necessary. 

Minimally invasive procedures

Most patients are referred for minimally invasive procedures when their hemorrhoids do not respond to conservative therapy.  The aim of minimally invasive hemorrhoid therapy is to remove or cause shedding of excess hemorrhoidal tissue and induce scarring and fixation against the bowel wall.  The five main types of minimally invasive hemorrhoid procedures are ligation, coagulation, sclerotherapy, cryotherapy, and laser therapy.  In general, these treatments are safe and effective office-based procedures.  They can be performed during a patient’s first visit to a surgeon, often without the need for anesthesia or bowel preparation.

Ligation

Rubber band ligation (Figure 2)
The most commonly used procedure for treating symptomatic internal hemorrhoids is rubber band ligation.  This technique is appropriate for first, second, and some third degree hemorrhoids.  It is successful in approximately three quarters of patients. 

Rubber band ligation is performed via anoscopy using instruments conveniently termed “ligators.”  Ligators work by tenting up redundant hemorrhoidal tissue via suction or forceps then releasing rubber bands around tissue bases.  The tight encircling of hemorrhoids leads to tissue death from insufficient blood flow.  The hemorrhoid and rubber band usually fall off a few days after application.  An ulcer is left at the site of binding, which subsequently heals with scarring. 

Serial ligation sessions may be required, as most surgeons limit treatment to one or two columns per visit in order to prevent excessive tissue damage.  Following banding, many patients experience a sensation of anal “tightness,” which is alleviated by warm baths.  Patients are advised to avoid constipation during their recovery period with fiber supplementation and fluids.  Complications of rubber band ligation occur in less than 8% of patients and include bleeding, pain or spasm, urinary retention, and infection.  Minor complications, such as prolapse and thrombosis of adjacent hemorrhoids, can also occur.  Patients who are on anticoagulation should not undergo rubber band ligation because of an increased risk of post-procedure bleeding.  Symptomatic hemorrhoids often reappear several years down the line, but are usually treatable with additional ligation.

Doppler ligation
Doppler ligation is a recently developed technique that utilizes a specially designed anoscope, which contains a Doppler probe.  The flow sensitive Doppler transducer allows surgeons to identify and directly ligate hemorrhoidal arteries.  Though effective, this technique is more expensive and not significantly advantageous compared to the more traditional office-based procedures.

Coagulation

Coagulation techniques utilize heat to destroy excess hemorrhoidal tissue and promote scarring.  Like rubber band ligation, they are used in first, second, and occasionally third degree hemorrhoids.  Potential complications include pain (which probably occurs less often than with ligation) and bleeding.

Bipolar Diathermy (Bicap)
Bipolar diathermy is a type of cautery.  It is applied in short, less than one second pulses to generate tissue coagulation.  Multiple applications are often needed to produce adequate results, especially for higher degree hemorrhoids.  Because this method of hemorrhoid therapy does not eliminate prolapsing tissue, a few patients may still require hemorrhoidectomy.

Infrared Coagulation
As its name implies, infrared coagulation employs infrared light to produce heat and coagulation.  It must be delivered over several sessions.  Studies have shown a lower incidence of post-procedural pain with infrared coagulation compared with rubber band ligation, but perhaps a higher incidence of recurrence.

Direct current electrotherapy
This method of coagulation requires a longer application time (up to 14 minutes) compared with bipolar cautery and infrared coagulation.  Again, multiple treatments to the same site are sometimes required.  Direct current electrotherapy is very effective at controlling hemorrhoidal bleeding, but is less useful for prolapse.

Sclerotherapy

Sclerotherapy is one of the oldest methods of hemorrhoid treatment.  It involves the injection of caustic materials into hemorrhoids to bring about tissue destruction and scarring.  Sclerotherapy is quick, easy, and relatively pain free.  However, hemorrhoid recurrence after sclerotherapy is common.  

Cryotherapy

Cryotherapy utilizes cold temperatures, delivered via liquid nitrogen, to cause tissue injury and fixation.  It has been largely supplanted by the minimally invasive procedures discussed above because of a worse efficacy and higher rate of complication.

Laser therapy

Hemorrhoid removal using various types of lasers has been described, however these treatments are expensive and do not appear to provide any significant advantage over the other techniques.

Surgery

According to the American Gastroenterology Association, hemorrhoid surgery should be recommended for patients who cannot tolerate or fail minimally invasive procedures, patients with symptomatic grade III, grade IV, or mixed internal and external hemorrhoids, patients with symptomatic hemorrhoids as well as simultaneous anorectal conditions that require surgery, and patients who choose hemorrhoid surgery after being educated about treatment options.  Surgical therapy is also indicated in strangulated internal hemorrhoids and some thrombosed external hemorrhoids.  Surgical hemorrhoidectomy is the most effective treatment for hemorrhoids, though it is associated with the greatest rate of complications.   

Various methods of hemorrhoidectomy are currently available.  The 3 most commonly practiced procedures are Ferguson’s or closed hemorrhoidectomy, Milligan-Morgan or open hemorrhoidectomy, and stapled hemorrhoidectomy.  Park’s hemorrhoidectomy, Whitehead’s hemorrhoidectomy, and lateral internal sphincterotomy are used much less frequently.  Hemorrhoid surgery is usually performed on an outpatient basis.  Anesthesia can range from local to general depending on surgeon, anesthesiologist, and patient preferences.  Surgical hemorrhoid procedures are discussed below.

Ferguson’s or closed hemorrhoidectomy (Figure 3)
Closed hemorrhoidectomy is the surgical procedure most commonly used to treat internal hemorrhoids.  It consists of the excision of hemorrhoidal bundles using a sharp instrument, such as a scalpel, scissors, electrocautery, or even laser followed by complete wound closure with absorbable suture.  Typically all three hemorrhoidal columns are treated at one time.  Postoperative care includes frequent sitz baths, mild analgesics, and avoidance of constipation.  Closed hemorrhoidectomy is successful 95% of the time.  Potential complications include pain, delayed bleeding, urinary retention/urinary tract infection, fecal impaction, and very rarely, infection, wound breakdown, fecal incontinence, and anal stricture.  Although this technique has the most postoperative discomfort and pain, it does have the best long term results with the lowest recurrence rates.  New methods are being devised to decrease the pain associated with the surgery and should allow for a better patient experience.

Milligan-Morgan or open hemorrhoidectomy
In Milligan-Morgan hemorrhoidectomy, hemorrhoidal tissue is excised in the same manner as in Ferguson’s hemorrhoidectomy, however the incision is left open.  Surgeons may opt for open hemorrhoidectomy when the location or amount of disease makes wound closure difficult or the likelihood of postoperative infection high.  Oftentimes, a combination of open and closed technique is utilized.  Complications following open hemorrhoidectomy are similar to those that occur after closed hemorrhoidectomy.

Stapled hemorrhoidectomy (Figure 4)
Stapled hemorrhoidectomy is the newest addition to the armamentarium of surgical internal hemorrhoid procedures.  It has several aliases, including Longo’s procedure, the procedure for prolapse and hemorrhoids (PPH, Ethicon Endo-surgery, Inc., Cincinnati, OH), stapled circumferential mucosectomy, and circular stapler hemorrhoidopexy.  Stapled hemorrhoidectomy is mostly used in patients with grade III and IV hemorrhoids and those who fail prior minimally invasive treatments.  During stapled hemorrhoidectomy, a circular stapling device is used to excise a circumferential ring of excess hemorrhoid tissue, thereby lifting hemorrhoids back to their normal position within the anal canal.  Stapling also disrupts hemorrhoid blood supply.  Studies have suggested that stapled hemorrhoidectomy results in less postoperative pain and shorter recovery compared with conventional surgery, but a higher rate of recurrence.  Frequency of complications is similar to that following standard hemorrhoidectomy.  

Whitehead hemorrhoidectomy
Whitehead hemorrhoidectomy includes the excision of a circumferential ring of tissue at the anorectal junction.  It is rarely performed today secondary to a high incidence of postoperative complications, particularly anal stricture.

Submucosal or Park’s hemorrhoidectomy
In Park’s hemorrhoidectomy, the mucosa of the anus and rectum is incised and the underlying hemorrhoid tissue removed.  The aim of this technique is to minimize injury to the outer layer of the anal canal, thereby preserving sensory fibers and facilitating wound healing.  Park’s hemorrhoidectomy is seldom performed today, however, because it does not address the external component of hemorrhoids.

Lateral internal sphincterotomy
Lateral internal sphincterotomy or opening of the inner anal sphincter muscle is sometimes performed during hemorrhoidectomy in patients with high resting sphincter pressures.  It is hypothesized to reduce postoperative pain.  It is not used in most cases.

SUMMARY 

• Hemorrhoids are abnormally enlarged vascular cushions within the rectum and anus.
• Hemorrhoids are one of the most common anorectal disorders, affecting approximately 5% of the population.
• Although their exact cause is unknown, constipation and straining are thought to play a large role in hemorrhoid formation.
• External hemorrhoids arise below the dentate line.  Internal hemorrhoids originate above the dentate line and are graded according to degree of prolapse.
• The most common presentation of hemorrhoids is painless bleeding with bowel movements.  Excluding other causes of bleeding, particularly malignancy, is essential.
• Increasing fluid and fiber intake to minimize constipation and straining is the initial therapy for symptomatic hemorrhoids.
• Topical agents may help relieve hemorrhoid symptoms, but do not provide a cure.  Their use should be limited to one week.
• Thrombosed external hemorrhoids may require excision to provide adequate pain relief.  Excision should be performed within 48 to 72 hours.
• Most patients with symptomatic internal hemorrhoids that do not resolve with dietary modifications are candidates for office-based, minimally invasive procedures, often rubber band ligation.
• Patients who fail conservative and minimally invasive hemorrhoid therapies, and those with significant prolapse should be considered for surgical intervention.
• The three most commonly performed hemorrhoid surgeries are closed, open, and stapled hemorrhoidectomy.
• Surgical hemorrhoidectomy provides the most definitive treatment for hemorrhoids, but is associated with the highest rate of complications.

Figure 1.  Hemorrhoid anatomy

Illustration adapted from the
American Society of Colon and Rectal
Surgeons website – www.fascrs.org.
Artist: Russell K. Pearl, M.D