Dr. T. Balasubramanian M.S. D.L.O.
History: Endonasal approach
to correct nasolacrimal obstruction was described way back in 1800
by Caldwell, West and later during the begining of 1900 by
Mosher. This approach was not popular because of
technical limitations which included visualisation and availability of instruments for soft tissue and bone
removal. Toti popularised external dacryocystorhinostomy, and
this procedure was in vogue for quite sometime. The
introduction of rigid nasal endoscopies kindled interest in the endo
nasal approach to the lacrimal sac.
dacryocystectomy was performed by Celsus in 50 AD. McDonogh
was the first to perform endoscopic dacryocystorhinostomy in
Anatomy of lacrimal
Knowledge of lacrimal
apparatus is a must before embarking on endonasal lacrimal sac
surgery. The lacrimal system consists of a superior and
inferior puncta at the medial ends of upper and lower eyelids.
These two drain into upper and lower
canaliculi. These two canaliculi join to form the
common canaliculus. This zone is known as the upper lacrimal
system. The common canaliculus inturn leads into
the lacrimal sac. The sac is about 12 - 15 mm long.
It eventually narrows and leads into the nasolacrimal duct
which drains into the inferior meatus of the nose. The naso
lacrimal duct is about 18 mm long. The sac and the duct
comprise the lower lacrimal system.
The junction between
the common canaliculus and the lacrimal sac is guarded by the
Rosenmuller valve. This valve prevents tear reflux.
representaion of lacrimal apparatus
The nasal end of
the nasolacrimal duct at the level of inferior meatus is
guarded by Hasner's valve.
Physiology of lacrimal
apparatus: Tears move from the eye into the nose through a
mechanism known as the lacrimal pump. Movements of the
lids cause the puncta to close against each other, pushing tears
into the lacrimal sac. Tears accumulating in the sac (lacrimal
lake) are further pushed down into the nasolacrimal duct when the
eyes open because of the relative negative pressure caused in
the lacrimal lake.
Location of lacrimal sac: A
good intranasal landmark for the location of lacrimal sac is the
anterior portion of middle turbinate, the sac lies just lateral to
it. The lacrimal fossa is bounded by
the anterior lacrimal crest, which consists of the frontal process
of the maxillary bone. The posterior lacrimal crest is made up of
the lacrimal bone itself.
Intranasal landmark for locating the
The maxillary line is a mucosal projection along the
lateral nasal wall that serves as a landmark for endoscopic sinus
and orbital procedures.
Indications for Primay endoscopic
1. In the management of tearing
associated with primay acquired nasolacrimal duct obstruction
Infection of lacrimal sac associated with primary acquired
nasolacrimal duct obstruction
3. Nasolacrimal duct obstruction
secondary to specific inflammatory or infiltrativer disorders
The level of obstruction should be distal to the junctionof the
lacrimal sac and the duct.
5. In the management of lacrimal duct
injuries associated with sinus surgeries
1. Presence of a firm indurated mass above
the level of medial canthus.
2. Bloody epiphora
3. Presence of
bony destruction as seen in radiological films
is essentially reflux tearing: the main
gland over compensates secretion because of lack of secretion from
minor glands of along the lid margin.
History & patient
1. History of unilateral or bilateral
tearing must be sought. Unilateral tearing mostly indicates
2. Nature of the discharge must also
be sought i.e. whether clear or purulent
factors, such as allergies should be elicited. Medication histories
are important as well as previous history of trauma or
4. On physical examination - palpate the region of the
nasolacrimal sac to see if you can elicit any reflex from the
5. Eyelids should be carefully examined for evidence of
excessive laxity, punctum should be examined for evidence of
obstruction or inflammation. Excessively lax eyelids could
cause epiphora. DCR may not help these patients
canaliculi must be probed using a Biwman probe. A hard
obstruction could be caused by bone or calculi, a soft obstruction
could be caused by obstruction by soft tissue.
Nasolacrimal duct can be further examined by irrigating the duct
with a syringe.
7. Jones test should be performed to
identify the level of obstruction:
Jones test: The
Jones test is a test of the patency of the nasolacrimal system. The
test is performed by placing fluorescein in the conjunctival sac and
seeing whether or not this fluorescein can be visualized in the
nose. If after a period of five minutes there is impaired outflow,
it is likely that there is an obstruction somewhere in the duct or
somewhere in the system. If you do not see any dye in the nose after
five minutes, then you can perform a secondary test, by irrigating
the duct. If after irrigating the duct no dye is found in the nose,
the dye has never really reached the lacrimal sac to begin with. The
obstruction is likely proximal. If you do see dye in your irrigate,
then dye did reach the nasolacrimal sac, and it is likely that your
obstruction is distal.
CT scan of paranasal sinuses should be
taken to identify the cause of nasolacrimal duct
surgery can be performed either by using General or local
anaesthesia. If general anesthesia is preferred, the nasal
mucosa should be decongested by placement of cotton pledgets dipped
in 0.05% oxymetazoline in the middle meatus, this is followed by an
injection guided endscopically of 1% xylocaine with 1:200,000
epinephrine into the lateral nasal wall and middle turbinate.
If local anaesthesia is preferred, topical anaesthesia is achieved
by the use of pledgets dipped in 4% xylocaine mixed with 1:200,000
adrenaline to pack the nasal cavity. 1% xylocaine with
1:200,000 adrenaline is used to infiltrate the lateral nasal wall
and middle turbinate for adequate anesthesia.
Localisation of lacrimal sac: The sac must be
identified endsocopically. A guide to its position is the
insertion of the root of the middle turbinate on the lateral nasal
wall and the maxillary line. In patients with distorted nasal
anatomy following previous nasal surgeries the use of
fibreoptic endoilluminator can be resorted to. This 20 guage
illuminator is advanced gently through the superior or
inferior canaliculus until a hard stop occurs signifying the
lacrimal bone medial to the lacrimal sac is identified. The
location of the sac can now be visualised
Mucosal incision: After localising the
position of the sac endoscopically, the lateral wall mucosa is
incised with a sickle knife and is elevated using a Freer
elevator. It will be of immence help if this
incision could be placed well anterior to the location of the
sac as this will allow adequate exposure of bone. The
incision is made vertically from inferior to superior.
After elevation the mucosa is removed using a Blakesley
Bone removal: To expose the lacrimal sac, the
bony lacrimal fossa must be uncovered first. The
endoilluminator if used will greatly help in identifying the
position of the sac. Bone removal can be performed using a
Kerrison's punch forceps or by using a motor and burr. The
bone removal should commence from the maxillay line and
should proceed anteriorly.
Opening of lacrimal
sac: After overlying bone removal the lacrimal sac can be
incised using a sickle knife. It will be helpful if an
assistant could tent out the medial wall of the sac with
lacrimal probes introduced through the canaliculi. The
whole of the medial wall of the sac is removed.
can be applied to the site of surgery to prevent restenosis of the
Advantages of endoscopic dcr:
1. There is
no external scar.
2. The lacrimal pump system is preserved.
Any concomittant intranasal pathology causing epiphora can be
4. Lacrimal sac mucosa is
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