Anatomical Considerations

The tear film is important for the integrity of the ocular surface and thus for sight. It consists of three parts: mucin, water, and lipid, which are produced by the lacrimal gland, the lids, and the outer surface of the eye respectively. The tears are evenly distributed by the blink mechanism.

The tears are eliminated through evaporation and drainage via the excretory system. It consists of the puncta, canaliculi, lacrimal sac, and the nasolacrimal duct. The latter terminates in the inferior meatus of the nose ( ▶ 1) ^{1,​ 2,​ 3,​ 4,​ 5} ( ▶ Fig. 15.1).

15.1.2 Examination of the Lacrimal Pathway

Tearing can be caused by hyperlacrimation or epiphora. The former describes an excess production of tears due to neuronal effects or disorders of the lacrimal gland as well as reflex secretion in ocular surface disorders or evaporative dry eye syndrome. ⁴

The accumulation of tears due to insufficient drainage is referred to as epiphora. The elimination of tears via the excretory system is dependent not only on the patency of the system but also on the position of the lid and an intact lacrimal pump. The lacrimal pump describes the different parts of the pretarsal orbicularis oculi muscle, which forms loops around the canaliculi and lacrimal sac and actively influences the tear flow by contraction. If constant tearing occurs due to malposition of the eyelid (retraction, ectropion) or reduced orbicularis oculi muscle tone, it is referred to as functional epiphora.

A blockage of the lacrimal drainage system can be classified by the anatomical localization and the degree of stenosis (absolute or relative). The clinically relevant anatomical localizations of lacrimal duct stenoses along with their recommended treatment options are summarized in ▶ Table 15.1.

The examination of a patient with epiphora is described in detail in the remainder of Chapter ▶ 15.1.2.

Evaluation of the Eyelids

The clinical examination starts with the inspection of the eyelids and of the periocular region (see Chapter ▶ 3.1). Significant lid laxity can be diagnosed by the “snapback test”: the lower lid is pulled downward with a finger and its repositioning is observed. If this happens spontaneously and rapidly, there is no laxity. A significant laxity is present if repositioning is delayed, if it requires blinking, or if there is no apposition to the eyeball at all. In the “distraction test” the eyelid is held between thumb and index finger, and drawn away from the eyeball. The distance between the eyeball and the eyelid is then measured. Significant laxity of the eyelid can be assumed when this is 10 mm or more.

Evaluation of the Lacrimal Excretory System

Dye Disappearance Test (DDT)

Fluorescein (a yellow dye that fluoresces green under blue light) is instilled into the conjunctival sac. After 5 minutes a blue light is used to examine whether the dye has been eliminated. If there is no dye detectable, a problem with lacrimal drainage is unlikely. This test is particularly useful in children, since diagnostic syringing usually cannot be done.

Jones Test

This test is rarely used due to its low sensitivity and specificity. Basically the DDT is carries out, but the investigator then attempts to detect fluorescein in the nose with a swab (Jones I). If the test is negative, the lacrimal ducts are flushed with saline (Jones II). A relative nasolacrimal duct obstruction (NLDO) is indicated when fluorescein is detected. If no dye can be detected, this either means an absolute or a canalicular stenosis, as there is no accumulation of fluorescein in the lacrimal sac.

ROPLAS Test

ROPLAS is an initialism for “regurgitation on pressure over the lacrimal sac”. It describes the expression of mucous or mucopurulent material via the canaliculi upon retrograde compression of the lacrimal sac. If secretions are accumulated in the lacrimal sac due to NLDO or atonic sac, the test is positive. It is helpful for children with lacrimal duct stenosis and when contemplating the indications for a dacryocystorhinostomy (DCR).

Diagnostic Probing

The canaliculus is probed using a Bowman’s probe with the lid held under lateral traction. A “soft stop” is an elastic resistance and indicates canalicular stenosis (the localization of the block can then be measured and the canaliculus on the opposite side likewise probed) or common canalicular stenosis. A “hard stop” is an indication of the patency of the canalicular system into the lacrimal sac. The probe is stopped by the bone of the lacrimal sac fossa.

Diagnostic Syringing

Syringing is performed through either the upper or the lower lacrimal punctum. The end point of the examination is whether the saline or water that is used reaches the patient’s pharynx. The patient will confirm patency, perhaps swallow or cough. The examiner should also pay attention to the pressure required for flushing. A 5-mL syringe with a blunt, short lacrimal duct cannula is best suited for this procedure. The lacrimal ducts are patent if 100% of the liquid flushed goes through. A patency with increased pressure or partial regurgitation occurs with partial (or relative) stenosis. A reflux of fluid via the same lacrimal punctum is an indicator of a canalicular stenosis. The immediate regurgitation of clear liquid via the opposite punctum occurs with common canalicular block (CCB), the delayed regurgitation, sometimes associated with mucoid flakes or pus, is indicative of NLDO. Sometimes, dilatation of the sac can be seen on syringing in these cases ( ▶ Fig. 15.2).

Imaging

Imaging of the lacrimal system by means of dacryocystography (DCG) was first described in 1909 by Ewing. A water-soluble or iodized, oily contrast medium is instilled into the lacrimal ducts via the canaliculus with a lacrimal cannula or a catheter and radiography (digital subtraction DCG), CT (CT-DCG) or MRI (MR-DCG) are carried out. This is helpful especially in posttraumatic stenoses, as with CT-DCG in particular the surrounding bony structures can be visualized. ⁴

15.1.3 Congenital NLDO

Epidemiology and Pathogenesis

Symptomatic congenital nasolacrimal duct obstructions (CNLDO) affect some 2 to 12% of newborns. ^{6,​ 7} The incidence is even reported as high as 20%, with the majority of cases developing spontaneous remission ⁸ and are therefore often not being presented for consultation. In children with Down syndrome a significantly higher incidence of 22 to 35% ^{9,​ 10} is reported. Anomalies such as punctum or canalicular atresias as well as lacrimal sac fistulas are rare causes of infantile epiphora. More often, CNLDO occurs in the area of Hasner’s valve at the opening into the inferior nasal meatus due to an incomplete canalization of the nasolacrimal duct. These “simple” stenoses are mostly membranous and unilateral. Other “complex” variants are bony or canalicular obstructions, ¹¹ as well as lacrimal duct stenoses, which are linked with dysmorphia or Down’s syndrome.

Clinical Signs

An accumulation of amniotic fluid in the lacrimal sac of the newborn is termed an amniontocele. Draining of the lacrimal sac is prevented by the obstruction in the area of the Rosenmüller and Hasner valves. Initially, the content is sterile, but can develop an infection over course of time and then lead to acute neonatal dacryocystitis.

However, CNLDO typically presents with epiphora, increased tear film height, and matting of the eyelashes through mucous or mucopurulent secretion. The symptoms often appear within the first 4 weeks of life. ¹² Spontaneous remission during the first year of life is reported in 90 to 97% of cases. ^{8,​ 12}

Treatment

For an amniontocele, massaging the sac in a downward direction can be tried. Due to hydrostatic pressure this can lead to drainage of the sac contents into the inferior nasal meatus. If this is unsuccessful, prompt probing of the lacrimal duct is recommended in order to avoid neonatal dacryocystitis.

Neonatal dacryocystitis is an emergency and must be treated with intravenous administration of antibiotics in order to avert progression into orbital cellulitis or sepsis. An abscess should be punctured with a small cannula and the fluid obtained should be sent for microbiological analysis including an antibiogram. During this procedure, antibiotics can also be injected directly into the abscess. Therapeutic probing of the lacrimal duct should be done a few days after the acute infection subsides. If this treatment is unsuccessful, a dacryocystorhinostomy should be carried out where necessary a few days later. ¹³

In the more common chronic course of CNLDO there is controversy with regard to the timing for an intervention. Therapeutic lacrimal duct probing during the first year of life leads to remission in up to 96% of cases. ¹³ Some authors report that the rate of spontaneous canalization decreases with increasing age of the child. ¹⁴ This is probably because, after the first year of life, persistent lacrimal duct stenoses are complex stenoses in most cases. Most authors recommend surgical intervention, primarily as probing, at the age of 1 year and before then conservative treatment with Crigler’s massage and, if needed, topical antibiotics. ^{15,​ 16}

There has been increasing discussion whether an earlier surgical intervention from the age of 6 months can be recommended. One argument in favor of this is the potential of congenital lacrimal duct stenoses to be amblyogenic. ¹⁷ The prevalence of amblyopia and anisometropia in children with CNLDO seems to be significantly higher than in children who are unaffected. ¹⁸ However, this hypothesis has not been confirmed to date. A further reason for early intervention is the parents’ wishes. Although conservative measures are possible and effective, the purulent discharge, the necessity for repeated treatment with antibiotics, and the massage do have an impact on the quality of life of parents and child. ¹⁹ Furthermore, the probability of developing acute dacryocystitis increases with the duration of the stenosis and reduces the success of probing. ²⁰

Irrespective of the timing of intervention, the question of which surgical procedure should be performed is also increasingly under discussion. Treatment options are:

• 
  

  Lacrimal duct probing.

  
  
• 
  

  Lacrimal duct probing with silicone intubation (mono- or bicanalicular).

  
  
• 
  

  Balloon dilation.

  
  
• 
  

  Lacrimal endoscopy.

  
  
• 
  

  Dacryocystorhinostomy.

Lacrimal Duct Probing

Depending on the age of the child, probing can be conducted mostly under analgosedation; general anesthesia is not necessary. Many authors in the United States and United Kingdom conduct this procedure as an “office procedure” without sedation, ²¹ but this can however only be done in children under 1 year of age.

First the puncta and canaliculi are examined and the upper punctum is carefully dilated with a Nettleship probe, and the lacrimal passage is irrigated with a cannula. Probing of the lacrimal duct can either be done with the long, slightly curved lacrimal cannula or with the Bowman probe (sizes 0 to 0000). The probing should be done primarily via the upper canaliculus to avoid injury to the lower canaliculus. It is assumed that due to gravity the majority of tears will flow out via the lower punctum, although varying results are reported on this in the literature. It is advisable to stand at the patient’s head end. The probe is pushed first into the ampulla and then into the horizontal part with the lid under lateral traction. Attention is paid to identifying obstructions. Once the periosteum is reached, the direction of the probe is changed downward, laterally and posteriorly, following the course of the nasolacrimal duct. The instrument normally slides on its own with the use of soft pressure in the appropriate direction. After passage through the nasolacrimal duct, the bend in the instrument is directed medially, and the resistance in the area of the Hasner valve is overcome with gentle pressure in order to exit into the inferior nasal meatus ( ▶ Fig. 15.3). Using force can easily result in a wrong passage. When this is suspected, the probe can be withdrawn and a new attempt made to push forward. The patency of the lacrimal system can either be confirmed directly by irrigation (the patient in analgosedation swallows spontaneously; in general anesthesia flushing can be performed using fluorescein solution and can be detected in the nose as in the Jones test) or by means of nasal endoscopy. The examination of the nose has the advantage that the surgery can be combined, if necessary, with a medialization of the inferior nasal concha, should the latter obstruct the ostium. To achieve this, a periosteal elevator is pushed under the concha and the concha is infractured medially. Postoperative medication with oxymetazoline nose drops and eye drops and antibiotic eye drops (e.g., azithromycin, kanamycin) for a week is recommended. ¹³ The parents should be informed about the possibility of minor bleeding from the nose or the puncta. This often occurs intraoperatively and postoperatively and is usually harmless. In the initial period after the intervention, an early treatment of any possible rhinitis with decongestant nasal drops is recommended to prevent further obstruction. Lacrimal probing can be repeated if necessary.

The success rate of lacrimal duct probing in the first 4 years of life for CNLDO is reported to be 70 to 92%. ^{22,​ 23} A more recent study found no statistically significant differences in the success rate of the primary probing related to the age of the children. ¹⁹

Probing and Silicone Intubation

The intubation of the lacrimal passage with a silicone tube is done in recurrences following previous probing or in complicated lacrimal stenoses. It is more physiological and significantly less invasive than DCR. General anesthesia is recommended for the intubation.

After the probing, a silicone stent is inserted into the lacrimal passage. Mono- and bicanalicular silicone intubation systems are available for this; the success rate is independent of the type of intubation. ²⁴ We use bicanalicular intubation with the rigid Jünemann probe ( ▶ Fig. 15.4). The probe, loaded with a 4–0 polypropylene thread, is inserted into the nasolacrimal duct and the metal probe is removed after retrieval of the thread in the nose. The suture remains as a splint for the silicone tube. The hollow tube is placed onto the punctual end of the suture and drawn into the nose. The procedure is repeated via the opposite punctum and the tube is knotted in the nose. Monocanalicular intubation likewise is done with a rigid system. The advantages of this method are the protection of the other canaliculus during the surgery, the avoidance of punctal erosion by a tight tube, as well as the simplicity of removal of the device in children. The disadvantage is the relatively traumatic retrieval of the probe from the nose. To date there are also flexible monocanalicular intubation systems available, which have an olive-shaped end of the metal probe and are recovered from the inferior meatus with a special hook (Crawford method). If necessary, the tube can be fixed with a nonresorbable thread to the nasal mucous membrane to avoid premature dislocation. It is recommended to leave the intubation in place for at least 4 weeks. In general a tube removal is recommended after 6 months. ²⁵ With a normal dye disappearance test it can be removed earlier to avoid complications.

The success rate of primary silicone intubation with CNLDO before the fourth year of life is reported as 89 to 94%. ^{24,​ 25} Here too there is evidence of a higher success rate in younger children. ²⁵

Balloon Dilation

Balloon dilation was introduced in the 1990s. ^{26,​ 27} For this procedure an inflatable balloon made of polyurethane on a semiflexible catheter is introduced into the nasolacrimal duct, inflated to 8 to 9 atmospheres (depending on manufacturer) and left for 90 seconds. The catheter is then removed. The effect is due to the dilatation of the duct and the Hasner valve. ²⁸ The success rate is 79 to 96%. ^{26,​ 29,​ 30}

General anesthesia is required for balloon dilation. A disadvantage of the procedure is the additional cost. Balloon dilation is mainly used in cases where probing has been unsuccessful.

Complications

Intraoperative complications of CNLDO surgery are epistaxis, injury to the nasal mucous membrane and the inferior nasal concha, as well as to the canaliculi. Some authors recommend packing the nose with 4% cocaine or oxymetazoline to minimize intraoperative bleeding and for a planned nasal endoscopy. ³¹ The use of Jünemann or Ritleng probes or the flexible Crawford probe for lacrimal intubation, along with careful probing, helps in minimizing of these complications. Bleeding is mostly self-limiting and requires additional nasal packing or coagulation only in rare cases. A false passage can be avoided by using the correct probing technique.

Bicanalicular intubation bears the risk of slitting of the puncta through erosion as a result of knotting the tube ends too tightly in the nose. With facial growth in children the intubation becomes tight and this causes the tube to cut in. These patients need regular follow-up and, if necessary, early tube removal. Intraoperatively, care should be taken not to knot the tube too tightly. A further complication is migration of the tube ( ▶ Fig. 15.5a) into the medial canthal area. This can occur either with monocanalicular intubation or with complete canalicular erosion. Particularly in children, silicone can lead to granuloma formation in the area of the puncta or in the nasolacrimal duct. This is one reason for possible re-stenosis even after DCR. Dislocation of the silicone tube ( ▶ Fig. 15.5b), for example, after rubbing in the medial canthus, can necessitate early removal of the tube and thus endanger the success of the treatment. A loop in the medial canthus, if untreated, can lead to corneal epithelial defects and ulcers.

Prognosis and Recommendation for Treatment

The overall prognosis for congenital lacrimal stenoses is very good, ⁷ with remission in 90% of cases. For atresias the prognosis is significantly poorer and dependent on the success of surgical reconstruction; however, data on this are not currently available. Simple congenital NLDO has the best prognosis with a spontaneous remission of up to 100% in the first year of life. Probing, silicone intubation, and balloon dilation likewise show very good results. Due to the high rate of spontaneous remission when the clinical course of the disease is uncomplicated, the general recommendation is to postpone surgical intervention until the child is 1 year old and instead perform Crigler massage. ^{20,​ 32}

After the first year of life probing is recommended as a primary intervention. Primary silicone intubation can be considered in case of narrow lacrimal passage or canalicular strictures.

There may be recurrence despite successful probing and postoperative decongestant measures. Repetition of probing with or without intubation and, if necessary, medialization of the inferior nasal concha is recommended. In our view, balloon dilation can be tried as next choice to avoid a DCR.

With tight NLDs, bilateral stenoses, Down’s syndrome, craniofacial dysmorphias, or following acute dacryocystitis, primary lacrimal duct intubation should be considered with the primary procedure because in these cases probing alone generally delivers poorer results. ²⁰

In bony stenosis, repeated re-stenosis, or recurrent dacryocystitis, a dacryocystorhinostomy has to be done. As an alternative, from the age of 2 years endoscopic lacrimal duct surgery is a newer, more physiological surgical approach.

15.1.4 Acquired Lacrimal Stenoses

Etiology and Pathogenesis

Acquired lacrimal stenoses do not occur only in childhood but can also occur also in adults. The prevalence of symptomatic acquired stenoses is reported in a US cohort study as ~30 per 100,000 inhabitants. ³³ Primary or secondary causes for this are inflammation, infection, neoplasia, trauma, or mechanical causes. In the following paragraph only the most common causes are addressed.

Punctal and canalicular stenoses often occur secondarily to involutional ectropion or chronic blepharitis. Stenosis can also occur in scarring conjunctival diseases, chronic topical treatment (e.g., for glaucoma), following epidemic keratoconjunctivitis and due to chemotherapy (especially breast cancer treated with docetaxel), acid burns, or trauma. ³⁴

Primary nasolacrimal duct stenosis (NLDO) mostly occurs in middle-aged women with an incidence of 20 per 100,000 inhabitants. The primary acquired NLDO is often described as PANDO (“primary acquired nasolacrimal duct obstruction”). Women have a narrower nasolacrimal duct than do men. ³⁵ Postmenopausal hormonal factors appear to cause an alteration in the mucous membrane, which in turn causes the stenosis or occlusion. ³⁶ Secondary NLDO mostly arises in intranasal pathologies (polyps, scarring, tumors) or granulomatous inflammations (sarcoidosis, Wegener’s disease), or posttraumatically following mid-face fractures. ³⁷

Clinical Signs

In most patients canalicular stenoses lead to epiphora. NLDO often presents with matting of lashes and mucous or mucopurulent discharge. Complications of NLDO include acute dacryocystitis (possibly with empyema formation), which may lead to orbital cellulitis or sepsis if left untreated ( ▶ Fig. 15.6a). Old and immunosuppressed patients are especially at risk.

NLDO in combination with common canalicular block produces an accumulation of trapped mucous in the dilated lacrimal sac, which is termed mucocele. An indolent, well-circumscribed swelling without signs of acute inflammation can be seen in the medial canthal angle inferior to the medial canthal tendon (MCT) ( ▶ Fig. 15.6b).

Treatment

If possible, treatment of secondary stenosis is primarily treatment of the cause (immunosuppressive therapy for granulomatous diseases, reduction of topical glaucoma treatment, and treatment of canaliculitis).

Acute dacryocystitis needs immediate treatment with intravenous antibiotics and, in case of abscess formation, with incision and drainage. This can be carried out with short topical anesthesia (local cold spray) or under general anesthesia. As with most abscesses, it is mandatory to ensure healing from the base of the wound (local application of antibiotic tablets or a tamponade into the abscess cavity). Once healed, dacryocystorhinostomy (DCR) should be carried out as soon as possible in order to avert a recurrence.

Punctal and canalicular stenoses can, if necessary, be treated by slitting (“punctal snip” operation) or by trephination and silicone intubation.

With distal and common canalicular stenoses as well as NLDO, dacryocystorhinostomy is a possible therapeutic option.

External Dacryocystorhinostomy (External DCR)

Addeo Toti first described the DCR procedure in 1904. The principle of the surgery is to create a direct connection between the lacrimal sac and the nasal cavity, thus enabling lacrimal drainage into the nose, bypassing the nasolacrimal duct. Most authors report a success rate of 90 to 95%. Revision surgery can be done in case of failure.

Indications for external DCR are PANDO, secondary NLDO, persistent CNLDO, mucocele, and chronic dacryocystitis. It can also be indicated in incomplete NLDO or common canalicular block (CCB), or for treatment of functional epiphora in facial nerve palsy (see Chapter ▶ 16). The contraindication for external DCR is acute dacryocystitis.

Steps of an External DCR The surgery is often performed with general anesthesia, but can also be done under local anesthesia (infraorbital and supratrochlear nerve block, local infiltration of the incision site) with sedation. At the beginning of the surgery, a nasal pack with Moffet’s solution is inserted into the nose near the location of the ostium at the insertion of the middle turbinate. Moffet’s solution contains epinephrine, cocaine, and bicarbonate as local vasoconstrictors and anesthetics. ³¹

The site of the incision is infiltrated with a local anesthetic containing epinephrine 1:200,000. The incision is made approximately 3 mm medial to the medial canthus, protecting the angular vein with a slightly bowed course of 10 to 12 mm length. A blunt pair of scissors is now inserted horizontally and the periosteum of the lateral nasal wall is exposed via blunt dissection. Only in some cases is it necessary to separate the anterior part of the MCT for a better view. The periosteum can be incised with a scalpel or directly reflected laterally with an elevator, taking the lacrimal sac with it. Now the anterior lacrimal crest and the lacrimal sac fossa are visualized. The ostium is initiated inside the fossa with the periosteum elevator. Once the ostium has been initiated, it is extended anteriorly with a bone punch (Kerrison, Citelli), posteriorly by removing the anterior ethmoidal cells, superiorly to about 2 mm above the medial canthus (here the MCT can be a good guide), and inferiorly up to the edge of the bony nasolacrimal canal. ³⁸ The expansion of the ostium superiorly should be done carefully, avoiding the injury of the cribriform plate with consequent liquorrhea. A frequently occurring anatomical variant of the ethmoidal cells are the so-called agger nasi cells, part of the ethmoid displaced anteriorly between lacrimal sac fossa and nasal cavity. The agger nasi cells can cause pneumatization of the lacrimal bone and the lacrimal process of the maxillary bone. In these cases, during osteotomy a cavity lined with a thin mucosa is encountered, and only after breaking through a second bone is the nasal mucosa seen. In case of doubt, the nose can be probed with a curved artery forceps. The nasal mucosa is now infiltrated with local anesthetic and epinephrine and the lacrimal sac is tented with a Bowman probe and incised lengthwise. It is important to incise the sac along its entire length as otherwise, although the ostium might be patent, a “sump syndrome” (accumulation of secretion in the residual lacrimal sac) can occur. Further incisions are made to fashion anterior and posterior mucous membrane and lacrimal sac flaps. The posterior ones can be excised or anastomosed. If a posterior mucous membrane anastomosis is planned, this is the next step. Thereafter bicanalicular intubation can be done with a silicone tube. The tube is introduced into the nose via the ostium and knotted. It is important to ensure that the ends of the mucous membranes that form the anastomosis are adequately apposed and do not collapse into the ostium. The wound is closed in two layers (orbicularis and skin). A nasal packing is normally done at the end of the procedure. Postoperatively, topical antibiotics and nasal decongestants are given. The nasal pack is removed on the first or second postoperative day, the skin sutures after a week. The intubation remains in place for 6 weeks to 3 months in most cases; in complicated cases (revision surgery, following dacryocystitis, traumatic NLDO) it can be left for a longer time ( ▶ Fig. 15.7).

There are numerous variations of the technique described above. The success rate is roughly 80 to 99%. ³⁹ This is more dependent on the experience of the surgeon than on the variation. The use of anterior vs. anterior and posterior mucosal flaps for anastomosis seems to have no influence on the success of the surgery, ⁴⁰ nor does the intraoperative use of 5-fluoruracil. ⁴¹ In some studies, intraoperative use of mitomycin C has shown positive effects on keeping the ostium patent and is, where necessary, a possible adjuvant therapy, namely in revision DCRs. ^{42,​ 43} According to a meta-analysis, silicone intubation seems to have no influence on the patency of a primary DCR. ⁴⁴

Conjunctivodacryocystorhinostomy (CDCR)

CDCR is the creation of a connection from the conjunctival sac into the nasal cavity through an external DCR, thereby circumventing the canalicular system. The main indication is proximal bicanalicular stenosis. A glass tube (Lester–Jones or Putterman tube) or silicone tube is inserted into the conjunctival sac, exiting in the nasal cavity. The method has a high complication and failure rate and is very intensive in postoperative care for the patient. The surgery is therefore limited to rare indications ( ▶ Fig. 15.8).

Stay updated, free articles. Join our Telegram channel

Join