Disorders of the Upper Lacrimal System



Fig. 11.1
Schematic diagram showing the development of lacrimal system between the maxillary and frontonasal process (Photo Courtesy: Dr. Himika Gupta)



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Fig. 11.2
Schematic diagram showing the out-budding of solid canaliculi from the lacrimal rod (Photo Courtesy: Dr. Himika Gupta)


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Fig. 11.3
Schematic diagram showing the process of canalization (Photo Courtesy: Dr. Himika Gupta)




Disorders of the Punctum


The punctum is the entrance to the lacrimal outflow system and, hence, is of sacrosanct value in terms of disease recognition and its subsequent management. The spectrum of punctal disorders is wide and varies from a mild stenosis to punctal agenesis. Table 11.1 outlines the proposed classification of punctal disorders, which we believe will help in better understanding and building standardized protocols. Certain disorders like punctal and canalicular trauma would be discussed in Chapters 16 and 15 “Lacrimal System Trauma” and canaliculitis in Chapter “Infections of the Lacrimal System.”


Table 11.1
Proposed classification of punctal disorders





























A. Primary punctal disorders

 1. Punctal agenesis

 2. Incomplete punctal canalization

 3. Punctal stenosis

 4. Supernumerary puncta

 5. Ectopic punctum

B. Secondary punctal disorders

 1. Peripunctal disorders

 2. Punctal trauma

 3. Punctal ectropion

 4. Iatrogenic punctal disorders

 5. Contiguous punctal involvement in systemic disorders


Punctal Agenesis


Proximal lacrimal outflow dysgenesis involving the punctum and canaliculus is a sparsely documented entity in the literature [112]. The term punctal atresia has been used interchangeably with punctal agenesis as well as for a spectrum of punctal disorders varying from a fine membrane in the punctum to its absence itself [111]. It is important therefore to clearly differentiate punctal agenesis from other congenital punctal disorders.

The basic etiopathogenesis of punctal agenesis is likely to be failure of canaliculi out-budding from the upper end of the solid lacrimal cord in an embryo of 18–24 mm (Fig. 11.2) [9]. It is very rare to have intact canaliculi with a punctal agenesis [13, 14]. Welham and Hughes reported 89 % (n = 19) of the patients with punctal agenesis to have concomitant canalicular agenesis [15].

The diagnosis of punctal agenesis should include a careful history and examination. History of epiphora and other symptoms may be variable depending upon the agenesis of single or both puncta of the eye. Patients with a single punctum missing may have mild epiphora. Severe epiphora usually indicates an associated nasolacrimal duct obstruction. Associated redness and discharge are also seen. In contrast, patients with both puncta missing have universal epiphora but are usually not very symptomatic and do not have redness or discharge. Lyons et al. [3] in their series reported 78 % of the eyes with single punctum missing (n = 41) presented with epiphora and 22 % presented with medial canthal swelling and features of dacryocystitis. As against this, 100 % of the eyes with both puncta missing (n = 53) presented with epiphora, but none had any discharge or dacryocystitis. Clinical examination by slit lamp would show absence of the punctal papilla, absence of any transilluminant membrane, absence of any dimple in the area of the punctum, and occasionally the presence of eyelashes medial to the punctum in the pars lacrimalis area of eyelids (Figs. 11.4 and 11.5).

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Fig. 11.4
Clinical photograph showing a lower punctum agenesis. Note the cilia in the pars lacrimalis portion of the eyelid


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Fig. 11.5
Upper punctal agenesis. Note the absence of punctal papilla

Punctal agenesis has important ocular and systemic associations. Lyons et al. [3] found 23 % of their cases (n = 57) to have ocular abnormalities like lacrimal fistula, blepharitis, distichiasis, eyelid tags, absence of caruncle, and divergent strabismus. Punctal agenesis has a well-known association with systemic syndromes like ectodermal dysplasia [1, 6], Hay-Wells [1], and Levy-Hollister syndromes [8]. In addition it has been found that patients with both puncta missing showed intraoperative anatomical variations like aplasia of the lacrimal crests, sac hypoplasia, and large anterior ethmoidal air cells [3].

Management of punctal agenesis is challenging. Patients who have a single punctum missing and are asymptomatic may be observed without any intervention. However, probing is warranted in those who have associated nasolacrimal duct obstruction and most would do well. Failure of probing is an indication for a dacryocystorhinostomy with a Mini-Monoka tube. Lyons et al. [3] performed probing in 24 % (n = 41) of the eyes with a single punctum missing, DCR in 31 %, and DCR with Lester Jones tubes in 17 % of these patients. Patients with both punctum missing but with minimal symptoms can be observed. For those with severe symptoms, we prefer to manage using an endoscopic placement of Lester Jones tube (Fig. 11.6) or Gladstone-Putterman tube without an actual dacryocystorhinostomy (Fig. 11.7) [16]. However, there are many techniques described for Jones tube insertion in these patients, and individual surgeon preferences are based on what suits them best [1721]. We do not advocate any retrograde approach or cutting down of the canaliculus or canaliculotomy, since these are cumbersome procedures and the results in the literature are not very encouraging [3, 13, 14].

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Fig. 11.6
Lester Jones tubes


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Fig. 11.7
Endoscopic view following CDCR with Lester Jones tube


Incomplete Punctal Canalization (IPC)


Incomplete punctal canalization is a term that refers to a form of punctal dysgenesis with membranes. The term was first described by Ali et al. [22], who studied 55 such dysgenetic puncta. The pathogenesis of punctal membranes is unknown but is believed to either represent failed dehiscence of the epithelium overlying the normally formed canaliculi or failure of canalization of the most proximal part of the lacrimal apparatus. This dysgenesis is not found to have any systemic association although associated lacrimal system anomalies like canalicular stenosis and congenital nasolacrimal duct obstruction are reported [22]. Patients typically present in the first decade with symptoms of epiphora since birth or infancy. Clinical examination reveals punctal membranes which could be external or internal. The external membrane (EM) variety, which is also called IPC-EM, typically covers the external surface of the puncta and hides it beneath, giving a false impression of punctal agenesis (Fig. 11.8). The internal membrane (IM) variety, which is also called IPC-IM, typically demonstrates blurred punctal margins but, just at the entry into the puncta, covers it entirely with a membrane. The membranes usually appear translucent (Fig. 11.9). Clinical diagnosis is based on a high degree of suspicion of a slight avascular dimple at the site of the puncta, and the membrane tends to stand out as a translucent structure from the surroundings if indirect illumination is used with the help of a slit lamp and a thin slit beam is placed perpendicular and adjacent to the punctum.

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Fig. 11.8
Clinical photograph showing IPC-EM variety. Note how closely it mimics punctal agenesis


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Fig. 11.9
IPC-IM variety. Note that the blurred punctal margins can still be made out

Ali et al. [22] found that external membranes (EM) over the puncta were noted in 86.4 % and internal punctal membranes (IM) in 13.6 % of their patients. The punctal membranes on histopathological examination uniformly were fibrovascular membranes without any signs of inflammation.

Management of IPC is usually simple. A membranotomy using a slow taper punctum dilator is almost always helpful. Once the membrane is overcome, the surgeon would find a normal punctum beneath, and usually the canaliculi and the rest of the lacrimal outflow are found to be normal (Fig. 11.10). Intubation is helpful for the rarely associated canalicular stenosis; however, the authors do not advocate the use of routine intubation following membranotomy, since the diameter of the punctum is fairly large following the procedure and does not tend toward restenosis later on. With a simple membranotomy and occasional adjunctive procedures, the anatomical patency was found to be 100 %, and the relief from symptoms was seen in 91 % (20/22) of the patients [22].

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Fig. 11.10
IPC: following membranotomy, the canaliculus was found to be normal


Punctal Stenosis


Punctal stenosis is not an uncommon disorder of the punctum. It is an important cause of epiphora and accounted for 8 % of all patients presenting with epiphora in a tertiary care Oculoplastics practice [23]. Table 11.2 enlists the frequent causes of punctal stenosis [2, 12, 2426]. The pathogenesis is still elusive, but it is important to remember in this regard that the punctum being the entry point for tears is exposed to all the possible soluble irritants that an ocular surface encounters. The widely believed hypothesis that has been supported by histological studies [27] is a common mechanism involving inflammation leading to fibrosis and subsequent stenosis.


Table 11.2
Common causes of punctal stenosis



























 1. Involutional or age related

 2. Conjunctivitis (HSV, HPV, chlamydial)

 3. Eyelid infections

 4. Topical medication toxicity (timolol, latanoprost)

 5. Systemic medications (5-fluorouracil, paclitaxel)

 6. Lid malpositions

 7. Trauma (thermal)

 8. Chronic cicatricial disorders (Steven-Johnson syndrome)

 9. Peripunctal tumors

10. Systemic disorders (porphyrias, acrodermatitis)

11. Radiotherapy

In order to facilitate uniform protocols of management, Kashkouli et al. [12, 25] proposed a grading system for the puncta based on its size and shape. Table 11.3 enlists the different grades of punctal stenosis as published by Kashkouli with slight modifications, which our group believes are important. Figure 11.11 represents a normal round punctum, whereas Figs. 11.12 and 11.13 represent punctal stenosis.


Table 11.3
Grades of punctal stenosis















Grade 0 – punctal agenesis

Grade 1 – incomplete punctal canalization (IPC-EM and IPC-IM)

Grade 2 – recognizable but less than normal

Grade 3 – normal, round punctum (admits 26G canula)

Grade 4 – slit punctum <2 mm in size


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Fig. 11.11
A normal round punctum


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Fig. 11.12
Clinical photograph showing lower punctal stenosis


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Fig. 11.13
Grade 2 punctal stenosis

There are no uniform acceptable guidelines for the management of punctal stenosis. Several modalities described in the literature include punctal dilatation, one-snip punctoplasty, two-snip punctoplasty, three-snip punctoplasty, rectangular three-snip punctoplasty, four-snip punctoplasty, punctal punching with Kelly or Reiss punch, punctoplasty with mitomycin C, and inserting perforated punctal plugs, self-retaining bicanalicular stents, or Mini-Monoka [2834]. It is important to note that there is an increasing evidence in the literature about the benefits of Mini-Monoka as a noninvasive modality of managing punctal stenosis, and the author anticipates this to be one of the most acceptable modality in the near future. Mathew and Olver [28] reported punctal dilatation and placement of Mini-Monoka without any surgical snips as a simple yet effective procedure. Hussain et al. [29] in a very large series of 123 eyes showed Mini-Monokas to be effective in relieving epiphora in 82 % of the eyes at 6 weeks. Konuk et al. [30] showed a long-term success rate of 84 % with the use of perforated punctal plugs in their series of 44 procedures with a follow-up of 19 ± 13.4 months.


Punctoplasty


The earliest description of one-snip punctoplasty was by Bowman in 1853, later modified by Jones in 1962 [24, 25]. One-snip punctoplasty involves a single vertical cut on the conjunctival side of the punctum and vertical canaliculus till the ampulla (Fig. 11.14). Kashkouli et al. [25] combined a 2 mm horizontal one-snip punctoplasty starting from the ampulla, parallel to the lid margin, with additional Mini-Monoka insertion and reported a 77.4 % success (n = 53) at a mean follow-up of 18.5 months. In two-snip punctoplasty, after the vertical cut-like one-snip procedure, the second snip starts from the end of the first incision as a 2 mm horizontal cut and involves the ampulla (Fig. 11.15). Two-snip procedures are not very popular.

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Fig. 11.14
One-snip punctoplasty

May 26, 2017 | Posted by in OPHTHALMOLOGY | Comments Off on Disorders of the Upper Lacrimal System
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