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Proximal Lacrimal Obstruction – A Review
too frequently.
14
If the punctum is absent, a cut-down can be Figure 2: Lateral Common Canalicular Obstruction
performed, but often Jones tube placement is required. Secondary
causes of punctal obstruction such as ptosis should be treated in
themselves to correct the problem. It should be noted that absence
of puncta, e.g. congenital punctal agenesis, is often associated with
complete blockage of the canaliculi.
Canalicular Blockage at Proximal End
The therapeutic approach to patients with proximal lacrimal
obstruction involves the canaliculodacryocystorhinostomy (CDCR)
with retrograde canaliculostomy, whereby the probe is passed
backwards through the common canaliculus at the time of DCR.
This technique can only be carried out through an external DCR
Figure 3: Inferior Canalicular Obstruction
approach and not the endonasal DCR approach. The success rate
for this procedure has been reported to be 73% as judged by an
improvement in epiphora, with just under half of the failed cases
requiring placement of a Jones tube (see below).
16
One problem
with this technique is maintaining patency at the canaliculostomy
site; however, performing this procedure does not preclude other
options such as Jones tube placement.
Mid-canalicular Blockage
Previously, resection of the stenotic segment with end-to-end
re-anastomosis followed by stenting with a silicon tube was
proposed as the most efficacious approach. Again, this requires an Figure 4: Obstruction of Both Canaliculi – <8mm Left
external DCR approach and is technically difficult; therefore, with a
success rate of 64% it has not gained popularity among lacrimal
surgeons.
17
Not only is this procedure technically difficult,
18
but also
there is concern that the suturing materials may induce foreign-
body reactions and affect the patency of the canaliculus. The
authors have reported their experience of treating mid-canalicular
blockage using the endoscopic DCR approach and putting a silicon
stent through the stenotic segment of the canaliculus, with a
success rate of 54% at six months.
1
As a general rule, the more lateral the obstruction in the
canaliculus, the lower the chances are of successfully correcting
Figure 5: Obstruction of Both Canaliculi – >8mm Left
the stenosis at the primary site or by using DCR and stenting. For
these cases, bypassing of the canaliculi using a Lester Jones tube
may be necessary.
2
In the biggest series of Jones tube placements
published to date, Rose and Welham found a 91% rate of
satisfaction among patients for relief of epiphora;
2
however,
accurate placement of this tube is the key to a successful outcome.
If the lateral opening of the tube is positioned too posteriorly, it can
cause corneal irritations and abrasions. If the flange of the Jones
tube is positioned too anteriorly, it may cause ectropion.
The other main factor in the management of the Jones tube is
regular flushing as biofilms will gradually form inside the tube and Currently, the Jones tube is the gold standard for managing lacrimal
eventually cause blockage. Replacement of the Jones tube has obstruction, but the technique has recently been challenged by
been cited by Rose and Welham to be required in 44% of cases Schwarcz et al. in Los Angeles who demonstrated a success rate of 92%
occurring at an average time of 17 months post-operatively.
2
Loss of for modified conjunctivo-DCR as opposed to the conventional CDCR
the Jones tube has been cited as the main cause of failure;
19
as method where the caruncle is removed.
22
A modification to the Jones
such, Dailey and Tower have detailed the use of a frosted tube in tube has recently been considered that accommodates intranasal
order to improve its stability.
20
The use of a Medpor-coated tube anomalies such as a paradoxical middle turbinate.
23
Other alternatives
(linear high-density polyethylene) has also recently been shown to include a bypass without an osteal window,
24
transcanalicular yttrium–
have prevented tube extrusion over a 2.5-year follow-up period in a aluminium–garnet (YAG) laser
25,26
and balloon dilatation.
27–34
small series of 26 cases.
21
Placement of the tube is contraindicated
in patients who are unlikely or unable to undertake the necessary A more recent alternative is the Ipswich lacrimal flap technique.
35
This
aftercare, such as children and the learning-disabled.
19
involves performing an endoscopic DCR and then converting it into a
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