The document describes the anatomy and physiology of the lacrimal drainage system. It details the production of tears by the lacrimal gland, their spread by the eyelids, and transport through the puncta, canaliculi, lacrimal sac, and nasolacrimal duct into the nose. It discusses tests to evaluate the lacrimal drainage system for obstructions, including lacrimal sac compression and probing. Surgical treatments for obstructions like dacryocystorhinostomy are also outlined, as well as acute dacryocystitis resulting from duct obstructions.

1. Dr. K. Vasantha M.S., F.R.C.S. Edin
Director RIO Chennai (Rtd)

2.  Production of tears by the lacrimal gland
 Spread by the lids
 Transport of tears through the puncta, canaliculi,
lacrimal sac and nasolacrimal duct

3.  Lacrimal puncta: These (one in the upper lid and one in
the lower lid) are located at the junction of ciliary and the
lacrimal portion of the lid margin.
 There is a slight elevation around the puncta – called
papilla
 The upper is 6mm and the lower 6.5mm away from the
inner canthus
 When we blink the puncta will move towards the groove
near the plica semilunaris

4.  This has two parts – vertical 2mm and horizontal about
8mm. At the junction of the two there is a slight dilatation
called the ampulla
 The canaliculi pierce the lacrimal fascia and then unite to
form a common canaliculus
 The common canaliculus then opens in to a small
diverticulum in the sac called the lacrimal sinus of Maier
at about 2.5mm from the apex of the sac
 The valve of Rosenmuller prevents reflux of tears back in
to the canaliculus

5.  The sac is located in the lacrimal fossa formed by the
lacrimal bone and the frontal process of the maxilla. The
fossa is bounded by the anterior and posterior lacrimal
crest
 The periorbita splits in to two and surrounds the sac to
form the lacrimal fascia.
 There is venous plexus in between the two layers

6.  The lacrimal sac is 15/5mm in size
 The part above the point where the canaliculi enter the
sac is called the fundus. It is 3-5mm in size
 The body of the sac is 10-11 mm and the junction forms
the neck of the sac

7.  Antero lateral- Next to skin the angular vein is situated
8mm from the medial canthus.
 The palpebral fibers of the Orbicularis oculi which are
present next are needed to squeeze the tears in to the
nasolacrimal duct into the nose
 The medial palpebral ligament covers the upper part of
the sac
 The lacrimal fibers of the Orbicularis and lacrimal fascia
cover the sac

8.  Medial to the sac the Ethmoidal sinus is situated
superiorly and the middle meatus is present inferiorly
 Posterior to the sac the lacrimal fibers of the Orbicularis,
lacrimal fascia and the septum orbitale are present

9.  Course downwards, backwards and laterally and opens
into the inferior meatus about 30mm from the openings
of the nose
 About 20/3mm in length and diameter
 The intraosseous part is 12.5mm in length. It lies in the
nasolacrimal canal formed by the maxilla and the nasal
concha and is lateral to the middle meatus
 The intrameatal part is 5.5mm in length

10.  The opening of the nasolacrimal duct into the inferior
meatus occurs just before or after birth.
 If this does not occur it is called congenital nasolacrimal
duct obstruction
 Often this will get canalized on its own in a few weeks
 Criggler’s massage also will help
 Rarely probing will be needed

11.  If there is overflow of ears due to excessive production it
is called watering
 Only when the overflow is due to obstruction it is called
epiphora
 This is more common in women due to narrow NLD
 In Africans as the duct is short and straight, it is rare

12.  Primary acquired NLD in which no cause is found
Secondary obstruction due to
 Injuries to the bone
 Infections causing canaliculitis
 Neoplasms like papilloma, squamous cell ca,
mucoepidermoid ca, lymphomas, hemangiomas
 Autoimmune diseases, chemotherapy and radiotherapy
causing inflammation

13.  Location, dimension and direction of the puncta must be
checked first
 The lower punctum will be directed away from the
eyeball in Centurian syndrome
 Constant rubbing in old age while wiping off the tears
also adds to this problem as the lower punctum will be
directed away due to laxity of the lids
 Pouting of the punctum is seen in canaliculitis which is
often due to Actinomyces infection

14.  Chronic infection like conjunctivitis and blepharitis can
cause fibrosis around the puncta appearing like a white
ring around the puncta – punctoplasty will be effective in
these cases
 In a stenosed punctum this white ring will not be there.
Here punctoplasty will not help. This occurs with
prolonged usage of 5 fluorouracil and miotics
 Foreign bodies in the punctum also can cause watering. I
have seen a patient with an eye lash obstructing the
punctum

15.  Trichiasis
 Entropion
 Symblepharon
 Lid margin keratinization
 All of the above can be seen together in Stevens
Johnson’s syndrome
 Reflex tearing will occur due to the presence of foreign
bodies in the eye and other corneal lesions

16.  This is the first test performed if watering is noticed.
Important test to be performed in case of corneal ulcer
 When pressure is applied medial to the medial palpebral
ligament normally no regurgitation is seen
 A clear watery fluid is seen in atonic sac. Sometimes this
fluid may get ejected through the NLD also
 Reflux of mucoid fluid shows there is only obstruction
and no infection

17.  Reflux of mucopurulent material shows presence of
infection
 Blood stained discharge shows presence of dacryoliths
or malignancy
 While giving pressure one must also see whether the
fluid comes out through both puncta
 Syringing will confirm the presence of canalicular
obstruction and NLD obstruction
 If obstruction is at the level of common canaliculi the
fluid will egress through the other punctum

18.  This test will give as an idea about how fast the tear fluid
gets drained out
 A drop of 2% fluorescein is placed in to the conjunctival
cul de sac
 After 5 minutes if you don’t see any dye it means there is
no problem in exit of tears
 Can be performed in people who do not co operate for
syringing and in children
 But one cannot differentiate between obstruction, pump
failure and location of obstruction

19.  ‘0’ size Bowman’s probe is used
 Done if any obstruction is noticed while doing syringing
 The probe is passed through the canaliculus till a stop is
found
 If it is soft obstruction is at the level of the canaliculus
either individual or common. The distance at which the
stop occurs must be noted for planning the treatment
 If it is hard it means the probe has crossed the
canaliculus and reached the sac

20.  Three probe test is performed by passing three probes
through both canaliculi and a fistula if present
 In congenital fistula it will meet all the probes will meet at
a common point
 In an acquired fistula the probe will enter the sac and a
hard stop will be felt. This is because acquired fistula
follows drainage of pus following acute dacryocystitis

21.  Endoscopic examination is done to rule out any nasal
pathologies like hypertrophy of the mucosa, polyps or
tumors. Any anatomical variation like deflected nasal
septum are also ruled out
 Dacryocystography can be done in complicated cases to
find out the exact location of the block. This will be
needed following repeated surgeries, injuries and when
tumors are suspected
 CT to assess the bones and Nuclear lacrimal
scintigraphy to assess the pumping of tear fluid are
rarely done

22.  During olden days we used to excise the sac by making a
curvilinear incision of about 12mm in length about 3 – 4
away from the medial canthus along the lacrimal crest.
Care must be taken to avoid the angular vein
 After obtaining hemostasis the medial canthal tendon is
separated or cut.
 The sac is separated well by blunt dissection and then
cut from the nasolacrimal duct with a twisting action
 Complication - watering

23.  Even now in old people with dry eye it is better to do
dacryocytectomy, as whatever tear secretion is there will
stay in the eye. This is like a punctum plug
 When a person comes with a corneal ulcer and
dacryocystitis it is again better to do a cystectomy as we
have to remove the source of infection as early and
thoroughly as possible

24.  Here a by pass is made between the sac and the middle
meatus, by making an opening in the intervening bone
 In external DCR the connection is more successful as the
passage is lined by mucosa, since we suture the sac and
nasal mucosa. The bony osteum is also large. Since this
is membranous bone it will not fuse together again
 The sac region is anesthetized by blocking the infra
trochlear nerve.
 The nasal mucosa is anesthetized by blocking it with 4%
lignocaine soaked gauze

25.  A Freer’s elevator is used to separate the periosteum.
 After exposing the lacrimal fossa like this the bone is
punched with the blunt dissector and extended with the
sphenoidal punch. The lacrimal bone is very thin and can
be easily punched
 Then the sac and the nasal mucosa are cut to make two
flaps, which are then sutured
 It is better not to cut the medial canthal tendon here
 The wound is then sutured in layers

26.  Endoscopic endonasal DCR has the advantage of
absence of an incisional scar over the face. Besides that
the medial canthal tendon is not touched and the
lacrimal pump is not disrupted.
 Can be done even when acute dacryocystitis is present
as the skin is not touched.
 But the success rate is less than external DCR as the
bony opening is small

27.  The bony opening in endonasal DCR is made with Hajek
Kopfler forward punch and extended with a diamond burr
 Other method is to use a Ruggles’s rongeur to make a
opening in the lacrimal bone and extend it manually
 The sac is filled with fluorescein stained visco elastic
material. A cut is made in the sac wall and they are
placed far fro each other so that they will not fuse again
 Mitomycin C can be used to reduce fusion
 Silicone stents also can be placed in the canaliculi

28.  Normally though the tear fluid and the nasal mucosa
contain a large number of micro organisms the sac wall
is resistant to infection
 But when the duct is obstructed it can lead on to
infection of the sac wall and the surrounding tissues.
Then it is called acute dacryocystitis

29.  Pain, swelling and redness over the sac region and
watering
 In the initial stages there will be only induration. Later
pus formation will be seen
 It should be differentiated from preseptal cellulitis and
orbital cellulitis, esp. because this can occur in children
 If mucocele is there one can see swelling in the sac
region. Here there will not be any inflammation
 In children encephalocele also must be ruled out

30. The infection may spread and cause
 preseptal and orbital cellulitis
 Sub periosteal abscess
 Cavernous sinus thrombosis
 Fistula

31.  If the patients come in the induration stage itself, most
often the infection will come under control and we can
do DCR at a later date
 If pus formation has occurred it has to be drained by
making an incision in the dependant area. DCR has to be
done later once the inflammation subsides