Canaliculitis: what is it, causes, symptoms, treatment, prognosis

What is canaliculitis?

Canaliculitis Is an inflammation of the lacrimal canal. This is an uncommon condition that ophthalmologists often misdiagnose. This condition is difficult to eradicate. The condition can be misdiagnosed and treated as conjunctivitis, blepharitis, dacryocystitis, mucocele and chalazion, which leads to long-term soreness of the patient. Von Graefe was the first person to recognize the cause of canaliculitis as an infectious disease.

Canaliculitis can be primary or secondary. Secondary canaliculitis is often viewed as a complication of lacrimal occlusion in the treatment of dry eye syndrome.

Tubules are an important component of the proximal tear drainage system. They begin at the lacrimal opening and converge in most patients, forming a common tubule. These channels extend through the eyelids by about 8 millimeters. The superior tubule is shorter and narrower than the inferior one, and it has a sharp angle of inclination before fusion with the inferior tubule, forming a common canal. The lower tubule is almost completely horizontal.

Signs and symptoms

Canaliculitis can cause watery eyes, redness of the eyes and moderate soreness. Redness and soreness are most pronounced on the eyelid near the nose. Symptoms may be similar to dacryocystitis symptoms.

Causes

Traditionally it was believed that Actinomyces israelii is the organism responsible for canaliculitis. This organism was previously classified as a fungus, but is now considered an obligate or facultative anaerobic Gram-positive bacillus. However, recent studies show an increased incidence of staphylococcus and streptococcus. Many other organisms such as Eikenella, Lactococcus, Nocardia and fungi have also been isolated from canaliculitis patients. Research has shown that Pseudomonas aeruginosa (Pseudomonas aeruginosa)is the most common microorganism excreted in secondary canaliculitis; while other studies include species Hemophilus, views Actinomyces as well as Pseudomonas.

Epidemiology

Canaliculitis is a relatively rare disease. Studies have shown that it accounts for 2% to 4% of lacrimal diseases. The disorder can appear at any age from 5 to 90 years old, and the average age is estimated to be around 59 years old. Most studies have found a predominance of women. This may be due to hormonal factors that can interfere with tear production, making the tubules prone to microbial invasion. Some blame the use of cosmetics and the clogging of the canals with cosmetic particles as the cause. Secondary canaliculitis associated with occlusion of the lacrimal points is also more common in women, probably due to more female patients receiving puncture plugs to treat symptoms of dry eyes. Most studies have found a higher incidence of lower tubular lesions.

Pathophysiology

Canaliculitis can be divided into primary and secondary. Primary canaliculitis is inflammation of the lacrimal canal, usually caused by an infection. Secondary canaliculitis is inflammation of the lacrimal tubules secondary to lacrimal punctal occlusion or tubular intubation.

Diagnostics

Due to the various manifestations of this condition, canaliculitis may be misdiagnosed or diagnosed later. Symptoms are usually one-sided. Patients may have lacrimation, discharge, a swollen dot or swelling in the medial corner of the eye; these symptoms can be confused with chronic conjunctivitis, inflamed chalazion, or acute dacryocystitis. Other symptoms are the appearance of yellowish granules, calculi and stones. The yellowish granules are thought to be caused by species Actinomyces. Some studies have shown that watery eyes and eye discomfort are the most common symptoms, while other studies have shown eye discharge to be the most common manifestation. With secondary canaliculitis, other additional symptoms may be seen, such as intermittent bloody tears, spotting, or the presence of a tumor protruding from a point.

A thorough examination is imperative, and a high suspicion score is required to make a correct diagnosis of canaliculitis. Historically, the presence of calculi was considered strong evidence of canaliculitis, which was later extended to pericanalicular inflammation and puffiness. Various studies show that the most common signs of primary canaliculitis are puncture edema, eyelid edema, and discharge or calculi from the lacrimal points. The calculi are thought to be a sign of recurrence and require surgical removal to prevent further seizures. In the case of secondary canaliculitis, signs of tubular inflammation, an inflammatory mass, protruding from a point, granuloma formation, spotting, presence of dacryolitis, eyelid edema and erythema. Irrigation and probing can help localize migrated punctal plug in patients with secondary canaliculitis.

Clinical examination for canaliculitis should include a slit lamp examination of the upper and lower point, medial region of the eyeball, conjunctival fornices and douching of the lacrimal liquids. Although the diagnosis of canaliculitis is clinical in most cases, ancillary investigations can help confirm the diagnosis or assist in making a definitive diagnosis in patients with ambiguous symptoms.

The following studies can be performed in patients with canaliculitis.

- Microbiological culture.

Crops of discharge from the lacrimal openings, calculi, abscesses and smears from the conjunctiva. Aerobic and anaerobic cultures are usually required. However, in recurrent or atypical cases, cultures of fungi and mycobacteria can also be done.

- Histopathology.

Histopathological examination is most often performed on pronounced calculi. They may show the presence of actinomycetes or may consist of sterile necrotic tissue. In secondary canaliculitis, histopathologic examination of the extruded foreign body may show an inflammatory response at the margins. The histopathological features of the pyogenic granuloma can also be seen.

—​ Ultrasonic biomicroscopy (UBM).

UBM with a frequency of 50 MHz and a resolution of 40 microns is one of the best methods for studying the tubular system. Its non-invasive nature adds to its benefits. He may show tubular changes and canaliculitis.

- Dacryoendoscopy.

This is an important study, especially in cases of secondary canaliculitis, for the localization of migrated lacrimal plugs.

- Dacryocystography.

Dacryocystography allows you to accurately establish in which area there is a stricture or obliteration, to determine the size of the lacrimal sac, to identify cicatricial changes, diverticula, internal fistulas, dilatation of the tubules, to get an idea of ​​the relationship of the lacrimal ducts with adjacent bone formations.

Treatment

It is believed that drug treatment of new-onset primary canaliculitis is effective in patients with early initiation of therapy. Conservative treatments include topical and systemic antibiotics, warm compresses, topical massage, douching, and irrigation. Numerous studies have shown that conservative treatment is ineffective in 80% of cases. The presence of calculi can help protect bacteria from antibiotics, thereby promoting resistance and inadequate response to treatment. Many authors now focus on early diagnosis and rapid initiation of surgical treatment for canaliculitis.

Various surgical options include point dilation or punctual curettage, canaliculotomy, canaliculoplasty with intubation and punctum-sparing canaliculotomy with monocanalicular intubation. Most studies have shown that canaliculotomy is a safe and effective procedure. A canaliculotomy involves an incision in the back of the tubule and removal of stones, calculi, necrotic epithelium, and other foreign bodies, followed by flushing with an antibiotic solution. The incision can be left open or closed with or without a stent.

It has been established that secondary canaliculitis is difficult to treat. Canaliculotomy with plug removal is considered the treatment of choice for canaliculitis associated with occlusion of the lacrimal points in the treatment of dry eye syndrome. Recurrent or complicated cases may require dacryocystorhinostomy, removal of any intracanalicular foreign bodies or foreign particles, and placement of a stent.

Forecast

Many factors can affect the long-term resolution of primary canaliculitis, including a low suspicion index, which can delay proper diagnosis and treatment of canaliculitis. As with many other conditions, treatment shifts from medical to surgical treatment in order to achieve resolution of the patient's condition in the least invasive way. Conservative methods may initially be successful, although the literature indicates that relapse rates are as high as 33% with medication alone versus 16% with surgery interference.

With secondary canaliculitis, conservative measures usually do not lead to a complete cure. Thus, canaliculotomy with plug removal is a common treatment.