Physiology of the Eyelids and Lacrimal System Methods of Examination in Oculoplastics

1. PHYSIOLOGY OF THE EYELIDS
METHODS OF EXAMINATION
ALEXANDER D. TAN MD, FPAO
PRESIDENT, Philippine Society of Ophthalmic Plastic and
Reconstructive Surgery
CLINICAL ASSOCIATE PROFESSOR, UP-PGH

2. Objectives
 Discuss the physiology of the human eyelid
 Discuss the functions of the eyelid
 Discuss the functions of the cilia and meibomian
glands
 Discuss the physiology of eyelid movement
 Discuss the lacrimal drainage system

3. Anatomy of the Eyelid

4. Upper Eyelid Anatomy

5. Functions of the Eyelid
 Maintain integrity of the corneal surface and tear film
 Maintains proper position of the globe within the
orbit
 Protection from the external environment
 Sensory function of the lashes
 Spontaneous and reflex blinking
 Secretions of the glands in the eyelid
 Regulates the amount of light
 Cosmesis

6. Cilia
 100 to 150 in the upper eyelid; half in the lower eyelid
 Surrounded by a neural plexus
 Each has an associated group of sebaceous glands
(Glands of Zeis)
 Life of 3 to 5 months
 Epilation : regenerates in 2 months; cutting 2 to 3
weeks
 Eyebrows: minimal function, tactile sensors from
objects approaching from above; facial expression

7. Meibomian Glands
 Imbedded within the tarsal plates; 20 – 40 in upper
eyelid, less in lower eyelid
 Forms the oily layer, most superficial layer of corneal
tear film
 Forms a hydrophobic barrier at the margin of the
eyelid preventing spillage of tears at the lid margin

9. Eyelid Movement
 Opens the eyelid:
 Levator Aponeurosis
 CN III
 Close relation with the SR
 Innervated as YOKE MUSCLES
 Mullers Muscle
 Smooth muscle ; sympathetic nervous system
 Frontalis Muscle
BELLS PHENOMENON: upward rotation of the globe 15
degrees; not found in reflex blink

10.  Orbicularis Oculi muscle : CN 7
 Orbital
 Preseptal
 Pretarsal
Eyelid Closure

11. Embryology of Lacrimal Drainage
 7 mm embryo: naso-optic fissure, a depression
bordered superiorly by the lateral nasal process and
inferiorly by the maxillary process.
 Naso optic fissure shallows, with a solid strand of
surface epithelium. This epithelium forms a rod.
 Canalization of the ectodermal rod begins at 32-36mm
stage, first in the lacrimal sac, canaliculi and lastly in
the NLD.
 Eyelids separate at 7mos AOG, puncta already open

12. Lacrimal Drainage
 25% is eliminated thru evaporation
 Blinking moves the tear film into the puncta
 Contraction of the orbicularis causes medial
displacement of the horizontal portion of the
canaliculus.
 Insertions of orbicularis onto the lacrimal sac causes
lateral displacement of the lateral wall of the lacrimal
sac when the orbicularis contracts

13. LACRIMAL CLEARANCE
 Gravity
 capillary attraction forces
 EVAPORATION
 Absorption by the conjunctiva
 Residual (Krehbiel) flow
 LACRIMAL PUMP
 Orbicularis oculi
Respiratory movements, cardiac circle/vein plexuses
Tears flow in ‘boluses’ Amrith 2005

14. Lacrimal Pump Theories
 Jones Theory: eyelid closure causes negative
pressure inside the lacrimal sac
 Doanes Theory: eyelid opening causes negative
pressure inside the lacrimal sac
 Tri-Compartment Theory of Becker: eyelid closure
causes negative pressure in superior aspect of the
lacrimal sac

15. Jones Theory

16. Rosengran Doane Theory

17. METHODS OF EXAMINATION
 Gross examination
 Eyelid Measurements
 Snap Back Test / Distraction Test
 Tearing and Lacrimal Apparatus Irrigation
 Probing and Irrigation
 Dye Disappearance Test
 Jones Test

20. Levator Function Measurement

21. MRD1 and Levator Function
 Normal MRD : 4 – 4.5mm
 Difference of 2: mild ptosis
 Difference of 3: moderate ptosis
 Difference of 4: severe ptosis
 Levator Function
 0-4 : poor
 5-7 : fair
 8 – 11: good
 >11 : excellent

23. Measurements
 Palpebral fissure
 Lid crease height
 Horizontal eyelid fissure
 Levator function
 Intercanthal Distance
 Lagophthalmos
 Bell’s phenomenon/ Pupil Size
 Orbicularis function

24. Eyelid Tumors
 Use a millimeter ruler
 Describe color, consistency, +/- movable, location,
signs of inflammation, edges
 Check for orbital signs (signs that tumor has crossed
the orbital septum)
 involves anterior or posterior lamellae
 Destroys / preserves normal structures (lashes,
puncta)
 Check for lymphadenopathy

25. Snap Back Test / Distraction Test

26. Eyelids and Lacrimal Drainage

27. Tearing
 Non-specific sign of ocular surface irritation or lacrimal
apparatus pathologies
 Refers to increased reflex tearing (lacrimation) or failure
of tears to drain properly (epiphora)
 May combine with other signs and symptoms like FB or
burning sensation, redness, pain, itching, discharge,
photophobia etc.

28. Lacrimal Drainage System

29. Important things to ask in the history of the
tearing patient:
1. Presence of associated symptoms : itchiness,
FB sensation, redness, eye pain, swelling
medial canthal area
2. Duration and aggravating factors: worse in
the morning, while in air conditioned rooms
3. History of surgery: exposed sutures, injury to
lacrimal drainage system

30. Lacrimation: Increased aqueous tear
production

31. Tear Production
 6 to 8 ul or 1.2 ul per minute
 Too much: irritation of the cornea or primary
hypersecretion of the lacrimal gland
 Crocodile tears: in CN7 palsy, due to aberrant nerve
regeneration
 Too Little
 Poor Quality

32. Foreign Bodies and Abrasions
Corneal Metallic FB Corneal Abrasion
Inspecting upper tarsal
conjunctiva

33. Corneal Pathologies
Corneal edema Central Microbial Keratitis
Herpes simplex Keratitis Corneal Epithelial Defect

34. Congenital Glaucoma
Buphthalmos with corneal edema

35. Epiphora: Blockage of lacrimal drainage
or tear overflow

36. Anatomy of the Lacrimal Drainage System

37. Anatomy
Puncta: 0.3 mm in diameter, 1 mm medial to the end of
the tarsal plate, inferior punctum more lateral.
Canaliculus: vertical and horizontal portions, in 90%
forms a common canaliculus (Ampulla of Maier)
Lacrimal Sac: 15 mm in length, anterior: anterior
lacrimal crest, med canthal tendon, medial: the
lacrimal maxillary suture and anterior ethmoidal air
cells, inferior: IO and angular vein.
Nasolacrimal duct (intraosseous): nasofrontal process
of the maxilla, angulated posteriorly, inferiorly and
laterally.

38. Nasolacrimal Duct Obstriction
•Common cause of tearing in newborn and in
adults
•Congenital NLDO: blockage of valve of Hasner
at inferior meatus of inferior turbinate
•Acqired NLDO: blockage of intra-osseous
portion of NLD.
•Usually in females
•Managed by doing a DCR
(dacryocystorhinostomy)

39. Congenital NLDO
Fluorescein Dye Test

40. Acquired NLDO with Dacryocystitis

41. Probing and Irrigation

45. Materials for Probing and
Irrigation

46. Possible results from LACRIMAL APPARATUS IRRIGATION/ localization of
obstruction
A. NORMAL
B. COMPLETE OBSTRUCTION : No fluid tasted, all the fluid refluxed thru
opposite punctum
C. PARTIAL OBSTRUCTION: some fluid tasted, all the fluid refluxed thru
opposite punctum
D. Canalicular Obstruction: no fluid tasted, fluid refluxed thru same punctum
E. Dacryocystitis : No fluid tasted, mucoid fluid refluxed thru opposite
punctum

47. Dacryoscintigraphy vs
Dacryocystography
Dacryoscintigraphy uses Tc 99 tracer dye, instilled thru the
culdesac, with serial photography
DCG uses lipiodol contrast injected thru the lacrimal apparatus,
then xrayed

48. Bony Orbit

49. Blow Out Fractures
 BLOW OUT FRACTURE : fracture of an orbital wall in
the presence of an intact rim
 FLOOR: orbital plate of the maxillary bone and
palatine bone
 Floor: shortest of all orbital walls ; equilateral triangle;
contains the infraorbital groove (maxillary CN5)
 First described by MACKENZIE IN 1844; term first used
by Smith and Converse in 1956

50. Mechanism of Blow Out Fracture

53. Fracture Patients
 Proptosis or Enophthalmos
 Diplopia and EOM restriction
 Step Down Deformity
 Hypesthesia
 Trismus / Malocclusion
 Crepitus / Pneumo orbitism

57. THE END