DCR (Dacryocystorhinostomy), lec.7

[Kademad]

hi all, how is it going? in the last lecture of opth. (I guess it was no. 6) dr. Najah talked about excessive watering of the eye and its causes, one of which is nasolacrymal duct obstruction and its Rx: DCR....
so I thought I could collect some info and images for those who didn't attend it...
I hope you'll find it useful


Epiphora, or abnormal tearing, occurs because of blockage in the lacrimal drainage system, which impairs normal tear channeling into the nose. Recurrent infection may also occur as a result of the stagnation. The dacryocystorhinostomy operation, which involves fistulization of the lacrimal sac into the nasal cavity, may alleviate the symptoms.

As normal access to the nose for the tears is impaired, a neopassage is defined from the lacrimal sac to the nose.

Etiology
The occurrence of symptoms may be related to congenital or acquired causes.
Acquired causes include recurrent dacryocystitis and canaliculitis; dacryolithiasis; lacrimal system tumors; nasal pathology obstructing drainage; and trauma, which may be iatrogenic. An unidentifiable cause contributes to an idiopathic etiology.

Pathophysiology
As a result of the blockage of the nasolacrimal duct, normal tear flow into the nose is impaired. This leads to epiphora. The stagnation of tears in the lacrimal sac and the adjacent conduits promotes infection and its accompanying sequelae.

Clinical
Patients may present to an ophthalmologist with socially unacceptable unilateral or bilateral epiphora interfering with vision. Persistent neglect of the symptom may induce chronic dacryocystitis with purulent drainage from the canaliculi. Inflammation of the skin in the region of the medial canthus may occur with acute exacerbations.

Relevant Anatomy

The lacrimal punctum, which lies near the medial end of each lid margin, opens into a canaliculus. The upper and lower canaliculi lead to the lacrimal sac, which lies in the lacrimal fossa formed by the frontal process of the maxilla anteriorly and the lacrimal bone posteriorly. The nasolacrimal duct originates at the inferior end of the lacrimal sac and slopes caudolaterally to open in the inferior meatus of the nose. This opening is protected by several variable folds of mucous membrane that act as valves preventing retrograde air aspiration.

The aqueous secretion of the lacrimal gland is covered by a film of mucus from the tarsal conjunctiva. This is further covered by a film of oily secretion from the meibomian glands. Evaporation is hence impeded, and the flow of tears occurs from lateral toward the lacus lacrimalis medially.

The palpebral fibers of the orbicularis oculi trigger blinking, a reflex act. Blinking pumps the tears out of the conjunctival sac. During the act, the puncta are turned inward and dip into the lacus lacrimalis. At this time, the lacrimal sac is drawn open, and tears are sucked up through the canaliculi. When the muscle relaxes, the lacrimal sac retracts to its original volume and the tears are pushed down the nasolacrimal duct


DCR (Dacryocystorhinostomy)

Tears are made primarily by the lacrimal gland, which is anatomically located in the upper lateral aspect of the upper eyelid. With each blink, however, tears are drained from the eye through the tear drainage system, into the nose. There are normally two openings to the tear drainage system; one in the upper eyelid and one in the lower eyelid. These tiny orifices are situated along the margin of the eyelid, closest to the nose, and are known as puncta. The puncta lead to tiny ducts known as canaliculi which lead to the lacrimal sac, situated just along the inside corner of the eye, on the side of the bridge of the nose. Tears are carried from the lacrimal sac down the nasolacrimal duct into the nose. It is usually toward the bottom of the nasolacrimal duct that obstructions of this passageway occur.



When an individual develops tearing due to acquired obstruction of the nasolacrimal (tear) duct, a DCR procedure is usually offered. However, diagnosis of the condition must be made first, and this usually requires one or more in-office tests by the ophthalmologist. This may include a dye disappearance test, whereby fluorescein dye is placed on the eye surface, and the disappearance between the two eyes compared. A second test for obstruction of the nasolacrimal duct might include irrigation of the tear drainage pathways. This non-painful test is completed by placing a small, blunt irrigating syringe just inside the initial opening of the tear duct, and irrigating fluid (water or saline) through the tear drainage system. If the nasolacrimal duct is determined to be relatively or completely obstructed, a DCR procedure is often appropriate.


The DCR Procedure

In this procedure, the tear drainage pathways are reconnected to the inside of the nose. A small incision is usually placed approximately midway between the corner of the eye and the bridge of the nose. The lacrimal sac is located, incised, and then connected to the nasal mucosa creating a new tear drainage pathway. Tiny plastic tubes (stents) are then placed in the newly created tear drainage pathway for a few months to prevent scarring of the tear drainage ducts, which might otherwise result in failure of the surgery. The tubes can usually be removed in the office with little if any discomfort or need for anesthesia.



The Balloon (Non-Incisional) DCR
A balloon DCR is similar to the incisional DCR in objective, although the procedure is completed without an incision. The surgeon advances tiny tubing through the blocked tear duct, utilizing an inflatable balloon to help create a new tear drainage pathway into the nose. The inflatable balloon is the same type of balloon used in coronary (heart) artery angioplasty procedures. The surgeon then places thin plastic tubing in the newly created tear duct system, which is generally removed in the office 4 to 6 months later. Removal of the tubing causes little if any discomfort and typically does not require anesthesia.



Take Care

[Nour]

Thanx kathum, Really nice work , nice pics...VERY NICE.

Besides, I was not understanding what was even epiphora, but understanding the rest of the lec.

Where do you get all these nice things from???

Thank you....

[ali al-kafaji]

wallah i was just posting the same thing but nour said it before me... great work u' ve done there ... det5achelna wallah.


ali

[Kademad]

I'm really glad that I could help, I hope u found it nice AND of benefit.

What I wrote was taken from many sources (3 websites)... let's just say I have a good wahis at searching the net.

Thanks for your encouraging words, into illi dat5ajilooni walla


Take Care

[Navigator]

Hi Kade (By the way I like to call you like that if you don't mind )

It was actually lecture 7 but that does not matter coz you did a very nice well organized job ...you are really so helpful ...Keep going chief

I wanted to say some words about the ophthalmology lectures so I'm going to say it here rather than in a new topic...

The lectures are very important and delicate and need to be attendet to be understood ...I'm saying that coz I tried to read them without attendance but i found them horrible....so I suggest for all those interested and those having difficulties in these lectures to attend them regularly although its time is somewhat annoying coz Dr.Najah is doing his best to make it clear

[Kademad]

first u can call me whatever u like besides Kade is being used by many friends now! so feel free

I'm soo glad that u found it useful, I hope others will, and those who didn't attend the lecture can see some benefit of it, and about what you said....

it's really different when u read an ophthalmology lecture that u have attended from a lecture that u haven't, buttom line...

attend opthalmology lectures