I.
II.
III.
IV.
Dry Eye Overview
A. Definition (DEWS 2007)
B. Causes of Dry Eye
1. Aqueous Deficient Dry Eye (ADDE)
a) Sjögren Syndrome
b) Non-Sjögren Syndrome, e.g.
(1) Age-related lacrimal gland deficiency
(2) Congenital Alacrima
(3) Lacrimal Gland Infiltration, Ablation or Denervation
(4) Obstruction of Lacrimal Gland Ducts
(5) Reflex Hyposecretion
2. Evaporative Dry Eye (EDE)
a) Intrinsic
(1) Meibomian Gland Dysfunction **
(2) Disorders of Lid Aperture and Lid/Globe Congruity
(3) Low Blink Rate
b) Extrinsic
(1) Ocular Surface Disorders
(a) Vitamin A Deficiency
(b) Topical Drugs & Preservatives (e.g. BAK)
(2) Contact Lenses
(3) Allergic Eye Disease
Dry Eye Epidemiology
Dry Eye Treatment Options
A. ADDE
1. Environmental modifications
2. Tear replacement therapy (i.e. artificial tear drops, gels & ointments)
3. Immunomodulatory agents (e.g. cyclosporine, steroids)
4. Secretagogues (?)
5. Nutritional support (e.g. flax-seed / omega-3 supplementation)
6. Punctal occlusion
7. Autologous serum
8. N-Acetylcysteine
9. Moist chamber goggles
B. EDE
1. Lid hygiene (i.e. “lid scrubs”)
2. Lid hyperthermia (i.e. warm compresses) & digital massage
3. Topical antibiotic (e.g. erythromycin)
4. Topical corticosteroid
5. Nutritional support (e.g. flax-seed / omega-3 supplementation)
6. Oral tetracycline drugs
Blepharitis
A. Anterior
1. Bacterial / “Staph”
2. Seborrheic
B. Posterior = Meibomian Gland Dysfunction (MGD)
V.
Blepharitis / MGD Epidemiology
A. Hom, et al. 1990
B. Venturino, et al. 2003
C. Lemp & Nichols, 2009
VI.
Anterior Blepharitis Treatment Options (typical)
A. “Staph” Blepharitis
1. Lid hygiene (i.e. “lid scrubs”)
2. Lid hyperthermia (i.e. warm compresses)
3. Topical antibiotic (e.g. erythromycin)
4. Topical corticosteroid – usually in combination with antibiotic
B. Seborrheic Blepharitis
1. Lid hygiene (i.e. “lid scrubs”)
2. Lid hyperthermia (i.e. warm compresses)
VII.
MGD
A. Represents one of the most under met needs in eye care today
B. Pathophysiology
1. Hyperkeratinization of ductal epithelium within meibomian glands
2. Leads to increased intraductal pressure, stagnation of normal meibum flow
3. Accumulation, thickening of lipids
4. Bacterial colonization and inflammation of the lid margins
5. Secondary effects include compromised tear film & associated dry eye
C. Classification of MGD
1. OMGD = Obvious Meibomian Gland Dysfunction
2. NOMGD = Non-Obvious Meibomian Gland Dysfunction
VIII.
MGD Treatment
A. Rationale:
1. Restore the normal chemistry, consistency and flow of meibum
2. Diminish ocular surface friction
3. Reduce ocular surface inflammation
B. Historical / Conventional Therapies:
1. Support the (lipid aspect of the) tear film
2. Lid hygiene (i.e. “lid scrubs”)
3. Lid hyperthermia (i.e. warm compresses) & massage
4. Topical corticosteroid – usually in combination with antibiotic
5. Nutritional support (e.g. flax-seed / omega-3 supplementation)
6. Oral tetracycline drugs (especially low-dose doxycycline)
C. Newer & experimental therapies
1. Topical cyclosporine-A (Restasis)
a) In a small clinical study, topical CsA failed to induce improvement
in symptoms, but did decrease the number of meibomian gland
inclusions in patients with meibomian gland dysfunction
2. Topical azithromycin 1% (AzaSite®)
a) Off-label use for blepharitis
b) Long half-life; achieves high concentration in ocular tissues
c) Anti-inflammatory capabilities, specifically against MMP-9, MMP-2
and certain lipases
d) AzaSite for blepharitis: Recent Clinical Studies
3. N-acetylcysteine
a) Mucolytic / antioxidant; potential anti-inflammatory capabilities
b) Utility in filamentary keratitis is well-known
c) Small clinical study showed significant improvement of both signs
and symptoms in patients with MGD after one month of therapy
4. Meibomian gland probing (Maskin technique)
a) Employs physical manipulation of meibomian ducts, similar to
punctal/canalicular dilation
b) Studies show significant and long-lasting improvement
5. Automated thermodynamic manipulation of glands
a) Novel device developed by Korb & Blackie (LipiFlow, TearScience)
b) Delivers heat directly to the conjunctival surface of the tarsus,
while simultaneously creating a “pulsating” motion to express
meibomian glands
c) Developed as an in-office procedure
d) Reports suggest significant improvement of both signs &
symptoms, and long duration of effect
IX.
References / Recent Publications:
1. Akyol-Salman I, Azizi S, Mumcu U, Baykal O. Efficacy of topical N-acetylcysteine in
the treatment of meibomian gland dysfunction. J Ocul Pharmacol Ther. 2010
Aug;26(4):329-33.
2. Arita R, Itoh K, Inoue K, Kuchiba A, Yamaguchi T, Amano S. Contact lens wear is
associated with decrease of meibomian glands. Ophthalmology. 2009 Mar;116(3):37984. Epub 2009 Jan 22.
3. Behrens A, Doyle JJ, Stern L, et al. Dysfunctional tear syndrome: A delphi
approach to treatment recommendations. Cornea. 2006;25(8):900-907.
4. Blackie CA, Korb DR, Knop E, Bedi R, Knop N, Holland EJ. Nonobvious obstructive
meibomian gland dysfunction. Cornea. 2010 Dec;29(12):1333-45.
5. Foulks GN, Borchman D, Yappert M, et al. Topical azithromycin therapy for
meibomian gland dysfunction: clinical response and lipid alterations. Cornea. 2010
Jul;29(7):781-8.
6. Foulks GN, Borchman D. Meibomian gland dysfunction: the past, present, and
future. Eye Contact Lens. 2010 Sep;36(5):249-53.
7. Haque RM, Torkildsen GL, Brubaker K, et al. Multicenter open-label study
evaluating the efficacy of azithromycin ophthalmic solution 1% on the signs and
symptoms of subjects with blepharitis. Cornea. 2010 Aug;29(8):871-7.
8. Korb DR, Blackie CA. Restoration of meibomian gland functionality with novel
thermodynamic treatment device-a case report. Cornea. 2010 Aug;29(8):930-3.
9. Lemp M, Nichols K. Blepharitis in the United States 2009: A survey-based
perspective on prevalence and treatment. Ocul Surf. 2009 Apr;7(2 suppl):S1-14.
10. Luchs J. Efficacy of topical azithromycin ophthalmic solution 1% in the treatment
of posterior blepharitis. Adv Ther. 2008 Sep;25(9):858-70.
11. Maskin SL. Intraductal meibomian gland probing relieves symptoms of obstructive
meibomian gland dysfunction. Cornea. 2010 Oct;29(10):1145-52.
12. Opitz DL, Tyler KF. Efficacy of azithromycin 1% ophthalmic solution for treatment
of ocular surface disease from posterior blepharitis. Clin Exp Optom. 2010 Nov 17.
[Epub ahead of print]
13. Perry HD, Doshi-Carnevale S, Donnenfeld ED, Solomon R, Biser SA, Bloom AH.
Efficacy of commercially available topical cyclosporine A 0.05% in the treatment of
meibomian gland dysfunction. Cornea. 2006 Feb;25(2):171-5.
14. Viso E, Gude F, Rodríguez-Ares MT. The association of meibomian gland
dysfunction and other common ocular diseases with dry eye: a population-based study
in Spain. Cornea. 2011 Jan;30(1):1-6.