O , my sustainer! Open my Heart

andmake my task easy for me

and loosen the knot from my tongueso that, they might understand my

speechSurah Taha (16:25-290)____Al Quran

DR. FAIZUR RAHMANProfessor of Ophthalmology

PESHAWAR MEDICAL COLLEGE

LEARNING OBJECTIVES

BY THE END OF THE SESSION THE STUDENTS

WOULD BE ABLE TO:Correlate the structure of the lacrimal system with its

function and clinical presentation in common clinical disorders.

Outline the clinical examination protocol for the assessment of lacrimal system in patient presenting with epiphora.

Lacrimal SystemConsist of two parts:

Tear productionTear drainage

Tear production:*Main Lacrimal gland*Accessory lacrimal glands

Glands of KrauseGlands of Wolfring

LACRIMAL GLANDS

Serous glandsSituated at the upper and outer angle of the orbit, just

within the orbital margin, in a depression on the orbital plate of the frontal bone (Fossa for the lacrimal gland)

EmbryologyLacrimal gland forms as a series of ectodermal buds that grow supero-laterally from the sup. fornix of the conjunctiva into the underlying mesenchyme. These buds then canalize forming the secretary units and multiple ducts of the gland.

Lacrimal sac and NLD develop as a solid cord of ectodermal cells between lat. nasal process &

maxillary process of the developing face.

LACRIMAL GLANDS-Anatomy.

Anteriorly divided by aponeurosis of levator palpabrae superioris into:

Upper orbital part

Lower palpabral partDucts are 12 in number, pass through the palpabral

part of the gland and open into the conjunctival sac, 4.5 mm above the upper border of the superior tarsus

Location

LACRIMAL GLAND LOCATION

LACRIMAL GLAND

LACRIMAL GLAND 12 ducts of the lacrimal gland pass from the

orbital part through the palpebral part into the superior conjunctival fornix.

In addition to Lacrimal gland, small accessory glands are also present in the conjunctiva.

In case of non functioning of lacrimal gland, these glands keep cornea wet .

MICROSCOPIC STRUCTURE

Lacrimal gland is lobulated tubulo-acinar structure. On cross section, the acini are seen as round or tube shaped masses of columnar cells.

Acini cells 80% are surrounded by Myoepithelial cells for squeezing out the secreted fluid.

RELATIONS

Palpebral part of Lacrimal gland lies below the

Aponeurosis of Levator palpebrae superioris. It extends into the upper eye lid.

Superiorly=Aponeurosis of Levator Palpabrae Superioris.

Inferiorly= Superior fornix- conjunctiva.

BLOOD SUPPLY Is from Lacrimal artery ( a branch of Ophthalmic artery) , and from Infra orbital artery ( a branch of Maxillaryartery)

VENOUS DRAINAGEVenous drainage is through Sup. Ophthalmic vein intocavernous sinus.

LYMPHATIC DRAINAGE Lymphatic drainage occurs into the superficial Parotid

lymph nodes.

NERVE SUPPLY Two types of nerve supply that is

Autonomic and sensory nerve supply. Autonomic nerve supply consist of

Parasympathetic and sympathetic components.

In parasympathatic system, the Nervous intermedius from the secretomotor nucleus of Facial nerve join a branch of Great petrosal nerve to form nerve of Pterygoid canal which goes to Pterygo palatine ganglion. From here nerve fibers pass through Maxillary , Zygomatic N; Zygomatico temporal and finally Lacrimal nerve.

In sympathatic system, superior cervical sympathatic ganglion,Plexus of nerves around ICA, deep petrosal nerve, nerve of Pterygoid canal, Maxillary nerve, Zygomatic N .Zygomatico temporal nerve & Lacrimal nerveSensory nerve supply; Lacrimal nerve.

SECRETORY INNERVATIONLACRIMAL GLAND

SECRETORY INNERVATIONPOSTGANGLIONIC

SYMPATHATIC FIBRERS

Accessory lacrimal glandsSame structure as main lacrimal glandVery small in sizeGlands of Krause:

20 in number, in the upper lid and 8 in the lower lid, deeply situated in the conjunctiva near the fornix on lateral side

Glands of Wolfring:are few in number, situated near the upper border of the tarsal plate

PhysiologySecretes tear, a slightly alkaline serous fluid.Consist of water and minute quantities of sodium

chloride, sugar , urea and protein.Contains lysozyme which is bactericidalStarts 3-4 weeks after birth.

Tear drainage systemConsist of puncta, ampula, canaculi, lacrimal sac

and nasolacrimal duct*Punctum:

Situated near the medial end of each eyelid.Face slightly posterior in normal condition.slightly evert the medial end of the eyelid and the punctum will become visible.

*Ampula: (Vertical canaliculus)The most proximal portion of the canaculus, measuring 2 mm.

Tear drainage…cont.*Horizontal canaliculus:

-8 mm long, in 90% the upper and lower unite to open in the lateral wall of the sac.

-In 10% both open separately.

-A flap of mucosa (valve of Rozenmuller) prevents regurg from the sac.

Tear drainage…cont.*Lacrimal sac:

- It is 10 mm long and lies in the lacrimal fossa.

- Lacrimal bone and frontal process of Maxilla separate it from middle meatus of nose.

*Nasolacrimal duct:

-Passes down medially & posteriorly to open in the inferior meatus.

-Opening is gauded by a valve. (valve of Hasner)

PhysiologyTear drainage:

Tears are drained from conjunctival sac by two mechanisms:1. Gravity.2. Active pump mechanism.

By gravity:Gravity plays a small part and most of the tears are drained by active pump.

PhysiologyActive pump (Suction):

-70% of the tears are drained through the lower punctum and 30% through the upper punctum-Upper and lower marginal strips of tears go medially-The tears enter the puncta by capillary action and suction.- Pretarsal orbicularis oculi splits into superficial and deep heads around the ampulae and some fibres are attached to the sac.

Physiology-During closure of the eye:

*Ampulae is compressed.

*Horizontal canaliculus shortens.

*Puncta move medially.

*Deep head of the orbicularis (attached to sac) causes dilatation of the sac.

PhysiologyAll these causes a negative pressure in the sac and tears

are sucked into the sac.

-When the eye closes, the sac goes to its original volume, forcing the tears into the nasolacrimal duct, and the puncta move laterally sucking tear into it.

Canalicular abnormalities:Very rare and often undiagnosed.

Absence of punctum:very rarely one or both the puncta may be absent congenitally, usually the site may be visible (congenital stenosis)

Congenital disorders.Congenital NLD blockage:

More common condition leading to epiphora in small children (non-canalization of the NLD cord)Managed by massages and simple antibiotics till the age of 6 months in the hope of spontaneous canalisationIf no improvement in 6 months the probing is tried three times till the age of 2 years.

Congenital disordersAfter the age of 2 years the success of probing decreases

and the child may require a DCR when he/she reaches the age of 6 years.

EVALUATION

History*watering, discharge, swelling and pain*usually prolonged, usually unilateral

Examination*Inspection

ectropion, swelling, fistula*Palpation

cystic swelling, any stones, regurg test

EVALUATION…Cont.*Slitlamp exam

*Punctal exam for malposition, stenosis*Press canaliculus for infection*Examine marginal tear strip*Froceful closure of lids—puncta may evert—lids may overlap*Fouroscein disappearance test—2 minutes

EVALUATION…Cont.Clinical tests

Probing*Hard stop*Soft stop

Irrigation*Canacular block*Partial block*NLD block

Patency of CanaliculusPatencyPatency of Canaliculusof Canaliculus

Topical anesthetics Topical anesthetics ––Pass the probe Pass the probe ––Canaliculus Canaliculus ––

Hard stopHard stop will Indicate will Indicate the the patencypatency of of canaliculus.canaliculus.

While While soft stopsoft stop means means obstruction of obstruction of canaliculus. canaliculus.

Syringing Can be done Syringing Can be done to confirm the to confirm the patencypatency of canaliculus.of canaliculus.

Jones testsJones I (Primary)

Hypersecretion orObstruction

Jones II (Secondary)Upper passages obstruction orPump failure

DacrocystographyTypes:Plain DCGDistention DCGMacro DCGCinematographyDacroscintigraphyContrast DCGDigital substraction DCG

DacrocystographyRadiopaque dyes:

Lipoidal in water or lipoidal with olive oil

Iodized oil

Neohydroil angioraphin

Dionosil aqueous

Conray

Diagonal viscous

Dacrocystography Conventional (Lipiodal ultra fluid is used)

Dacrocystography

Macrodacrocystography Computerized:

Subtsaction

Dacrocystography

Dacrocystography

Scintiligraphy

DynamicRadioactive technetium is usedSite of obstruction can be documented

Daffodil (Nargus)