ENDOSCOPIC - DCR

MADE EASY

Dr. Ausaf Ahmed Khan

Professor & Head of Department

ENT/Head and Neck SurgeryHamdard College of Medicine &

Dentistry Hamdard University, Karachi

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Topics Introduction Epiphora Causes of

epiphora Applied &

endoscopic anatomy of lacrimal apparatus

Importance of endoscopic-DCR

Endo vs. external DCR

Technique of endoscopic-DCR

Tips and pearls Causes of failure

Epiphora Epiphora (excessive tearing) is a common

complaint. From minor inconvenience to extremely

troublesome : a source of social embarrassment.

Partial or complete hindrance to lacrimal flow stagnation of fluid and debris purulent infection.

Lacrimal flow obstruction leads to ; epiphora, mucus discharge, excessive mattering, conjunctivitis, visual fluctuations of varying degree, peri-ocular swelling, dermatitis/cellulitis & abscess formation.

Estimated incidence of nasolacrimal obstruction : approximately 10 % at 40 years, 35–40 % at 80 years of age.

Epiphora/Excessive tearing causes

Irritation of eyes Foreign Bodies Ingrown eyelashes Eye infections Punctal stenosis Misplaced/abnormal

puncta Congenital

malformations NLD blockage Dacryocystitis Dacryoliths Defective blink reflex

Ectropion Entropion Facial trauma Facial palsy Canalicular atresia NLD stenosis in old age Nasal masses/infections Lower lid laxicity Growth in the sac Secondaries in sac

region

Obstruction of the NLD usually present with epiphora, it may also present with a mucocoele, pyocoele or recurrent acute dacryocystitis.

In majority of the cases : cause of obstruction is unknown.

Endoscopic-Dacryocystorhinostomy (DCR) is a well established treatment for epiphora caused by anatomic or functional obstruction of the Nasolacrimal apparatus.

A thorough understanding of the endonasal anatomy, wide marsupialization of the lacrimal sac, and meticulous care of the mucosa are critical for success

Epiphora

Anatomy of the Lacrimal Apparatus

Anatomy of Lacrimal apparatus

1. Lacrimal Gland 2. Lacrimal Ducts3. Lacrimal Puncta4. Lacrimal

Canaliculi5. Lacrimal Sac6. Naso-lacrimal

Duct7. Valves

Anatomy of Lacrimal apparatus1 – Lacrimal GLAND & Ducts

Anatomy of Lacrimal apparatus2 – Lacrimal PUNCTA

U/L Punctum width : 0.1-0.4mmDistance from med. canthus: 0.6mm

Anatomy of Lacrimal apparatus3 – Lacrimal CANALICULIVertical part : 2-2.5

mmAmpulla : V/H junction

90Horizontal part : 7-10

mmCommon canaliculus :

1-3 mm

Lacrimal probing

Anatomy of Lacrimal apparatus4 – The Lacrimal SAC

Lacrimal sac

Medial wall of right orbit… FP frontal process of maxilla, ALC anterior lacrimal crest, PLC posterior lacrimal crest, H

hammulus, LMS lacrimo-maxillary suture, FES fronto-ethmoid suture,

LP lamina papyracea, LB lacrimal bone, AF anterior foramen (AE Artery), PF posterior foramen (PE Artery), OC optic canal (optic N.),

SB sphenoid bone, MB maxilla, EMS ethmoido-maxillary suture

LF

Anatomy of Lacrimal apparatus4 – The Lacrimal SAC

Anatomy of Lacrimal apparatus5 – Naso-lacrimal DUCT (NLD)

Right nasolacrimal canal. View from the lacrimal fossa.

LMS lacrimo- maxillary suture, LB lacrimal bone, LO lacrimal orifice

Anatomy of Lacrimal apparatus

5. Naso-lacrimal DUCT (NLD)

ILP

SLC

SLP

ILCCC

NLD

Cadaver dissection of the Lacrimal drainage system

LS

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Projection of Lacrimal system canal in the LNW of Rt. nasal cavity.

L projection of the lacrimal system, MT middle turbinate, IT inferior turbinate, ST superior turbinate

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View through opening in the middle turbinate. FS frontal sinus, LC lamina cribrosa, FP frontal process, UP uncinate process, HS hiatus semilunaris, BE bulla ethmoidalis, MT middle turbinate,

LD lacrimal duct, IT inferior turbinate, SS sphenoid sinus

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Sagittal view outlining the lacrimal sac (S) and duct (D). Small arrows denote the common wall with the agger nasi

cell.

Sagittal view with the lacrimal sac and duct marsupialized by completely removing the medial bony and membranous

wall.

(a) Lacrimal system,Endoscopic view.

FP frontal process of maxilla, ML maxillary line, LB lacrimal bone.

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(b) Dissection of the lacrimal system,Endoscopic view.

FP frontal process of maxilla, IT inferior turbinate, LD lacrimal duct,

LP lamina papyracea, S septumUP uncinate process, MT middle turbinate,

Anatomy of Lacrimal apparatus7 – VALVES

• Valves allow unidirectional flow of tears

THE VALVE of ROSENMULLER – situated at the internal opening of the common canaliculus within the lacrimal sac. THE VALVE OF HASNER – lies at the distal opening of the lacrimal duct at the inferior meatus

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History of DCR Caldwell in 1893 – first reported case of

intranasal DCR Created a rhinostomy using an intranasal approach by

removing a portion of the inferior turbinate and following the nasolacrimal duct to the lacrimal sac – did not gain popularity.

Toti in 1904 – credited with first description of an external approach : is gold standard traditional surgical approach. Modified by Louis Dupuy-Dutemps and Bourguet.

Resurgence of interest in endoscopic technique Steadman and McDonagh and Meiring in1980s.

Massaro et al. produced the first report using an Argon laser Gonnering et al. later reported using both the CO2 and

KTP lasers.

Indications of DCR Symptomatic distal obstruction of the

Nasolacrimal duct that is not relieved by simple probing and syringing.

It is NOT indicated as the sole procedure where the site of obstruction lies in the canaliculi or puncti.

In case of functional obstruction (as evidenced by free flow on syringing along with failure of the pump system on scintigraphy) a DCR may be performed but the results tend to be variable.

The key for a correct indication is to exclude a presaccal stenosis, which is not suitable for an endoscopic procedure.

The best method to assess the site of obstruction consists of probing the lacrimal pathways: If it is possible to pass the proximal canaliculi (superior and inferior) and to enter the superior third of the lacrimal sac through the common canaliculus, a presaccal obstruction can be excluded.

Fluorescein dye tests (Jones I and II) or dacryocystographies (of any type) are no longer performed.

Since dacryocystographies use a probe to apply the contrast, there is no further need for a radiological evaluation if the probe passes.

Indications for surgery Indications for External or Endoscopic-

DCR NLD and common canalicular obstruction

with epiphora. Dacryocystitis. Symptomatic dacryoliths.

External DCR is chosen over Endo-DCR Trauma with medial canthal avulsion Suspected lacrimal sac diverticuli Lacrimal sac malignancy Pts with Down’s Syndrome ?

Comparison of the 3 techniques of DCR

Advantages of Endoscopic DCR

It provides better aesthetic result with no external scar.

It allows a one-stage procedure to also correct associated nasal pathology that may be causative.

It avoids injury to the medial canthus /scar formation.

It preserves the pumping mechanism of the orbicularis oculi ms..

Active infection of the lacrimal system is not a contraindication to endoscopic surgery.

It is superior to the external approach in revision surgery.

It is much less bloody and messy than the external approach.

The peri-operative time is shorter: SDC The success rate is comparable to the external

approach.

It requires specialized training in nasal endoscopic surgery.

The endoscopic equipment/setup is expensive.

Need an “open-minded” ophthalmology colleague ……

Hindrances in doing Endoscopic DCR

Pre-operative assessment Careful history Examination

Assessment of eyelids, tear film & lacrimal apparatus Rule out reasons for irritaive sources causing excessive

lacrimation; dry eyes, blepharitis, trichiasis, topical medications and exposure

Eyelid malposition; ectropion, entropion, horizontal laxicity Punctal anomalies; eversion, stenosis, conjunctival overlay.

Pre-operative assessment Office assessment of nasal cavity with

nasal speculum and endoscope. Identify pathologies like DNS/spur, AR,

acute infections, nasal polyps and malignancies etc.

Treat any acute infection or severe allergic rhinitis before surgery

Avoid NSAID’s, anticoagulants before surgery.

Pre-operative considerations Surgery is performed under general

anesthesia (hypotensive anesthesia) The nose is prepared with +/- local injections

and vasoconstrictive neurosurgical cottonoids. Infiltrate 2% Xylocaine with adrenaline into the

axilla of the middle turbinate and frontal process of maxilla

Place cottonoids soaked in xynosine/adrenaline in the middle meatus, along the frontal process of the maxilla and adjacent to the septum : GIVE ENOUGH TIME

Avoid unnecessary manipulation of endoscope and instruments during packing, avoid mucosal trauma esp. MT

A septoplasty is performed in case of an obstructing septal deflection.

The septal incision is ideally placed on the side contralateral to the DCR: This prevents inadvertent trauma to the

septal flap when the endoscope is inserted into the nasal cavity.

It minimizes clouding of the endoscope with blood from the septal incision.

Reduces the potential for the development of postoperative synechiae between the septum and LNW.

Endoscopic-DCR : made EASY

Instruments needed for Endoscopic-DCR

0 and 30 degree endoscopes

Light source/Camera/monitor

Suction No. 15 surgical blade Pointed diathermy Plester knife Rosen’s knife Sickle knife House (meatal) elevator Suction elevator, Freer’s

Kerrison bone punch Hajek-Kofler punch Blakesely forceps Thru-cut forceps Ball probe Lacrimal probe Punctal dilator DCR tube

Inspection andIdentification of landmarks

Inspection andIdentification of landmarks

UP

B

MT

Dimensions of lacrimal sac/flap

The lacrimal sac extends approx. 10 mm above the axilla of MT.

Topical and local anesthesia

Perform a septoplasty if needed:

Limited access restricts surg.

Dimensions of the nasal mucosal flap

A 30 endoscope provides better view of LNW.

Endoscopic view showing incision to create a posteriorly based mucosal

flap to expose the lacrimal bone and frontal process of the maxilla.

Endoscopic view of the raising of the mucosal flap.

Incision given by #15 blade

The lacrimal sac extends approx. 10 mm above the axilla of MT.

Incision given by monopolar diathermy

Elevation of flap

Removal of flakes of Lacrimal bone

The lacrimal bone extends from the FP of maxilla anteriorly

to the attachment of the uncinate process posteriorly.

This retrolacrimal region of the lamina papyracea is extremely thin, and inadvertent disturbance of the uncinate at this point can lead to orbital penetration.

Remember that the lacrimal bone and sac lie anterior to the orbit, and therefore the orbit is not at risk unless the surgeon is inadvertently posterior to these landmarks.

Removal of flakes of Lacrimal boneUsing Sickle and Rosen knifes

Removal of flakes of Lacrimal boneUsing Sickle and Rosen knifes

Remove the lacrimal bone up to the insertion of the uncinate : do not disturb the uncinate itself.

This retrolacrimal region where the uncinate inserts into the lamina papyracea is extremely thin, and inadvertent orbital injury might result.

Bone removal using Kerrison forcepsor Hajek-Kofler punch

Kerrison forcepsBone-punch

Hajek-Kofler punch

The Hajek-Koffler punch is faster at removing bone than the DCR bur : Perform as much of the removal of the hard bone of the frontal process of the maxilla with the Hajek-Koffler punch

Superior bone removal

When using the Hajek-Koffler punch, release the jaws after each bite : this

will prevent inadvertent trauma to sac.

Use of DIAMOND BURR for bone removal

Use diamond burr only when the punch is unable to grip the bone

adequately.

LS

NLDFl

AN

Very adequately exposed LS & NLD

Incising flap using KERATOME

Tenting the sacusing lacrimal probe

Make an incision into the sac only when lacrimal probe can be clearly seen through the sac wall.

When probing the lacrimal system, do so delicately : avoid trauma and a false passage.

Sac completely opened

Incision without inserting probe

f

Flap opened using 15 blade

Flap marsupialized and gelfoam placed

The common canaliculus opens high up on the lateral wall of the sac, and this area must be exposed in DCR for best results.

Flood of pus

Horizontal incision using SICKLE knife

Flap marsupializedApproximation of nasal flap

with sac wall using ball probe

Trimming of mucosal flap

Final approximation of flaps

Final approximation of flaps

Use of DCR tube

Working as a team with an oculoplastic surgeon : they

have requisite skills in probing and examining the lacrimal

system.

Causes of failure of DCR Inadequate osteotomy, Incomplete sac marsupialization, Cicatricial closure of the ostium Granuloma formation