Korb Associates

Boston, MA, United States

Korb Associates

Boston, MA, United States

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Korb D.R.,Korb Associates | Korb D.R.,TearScience | Blackie C.A.,Korb Associates | Blackie C.A.,TearScience
Eye and Contact Lens | Year: 2010

Objective: To determine whether Marx's line of the upper lid is visible in upgaze without lid eversion, thus raising the possibility that the line may not be the contact area for the upper lid wiping of the ocular surfaces. Methods: Consecutive patients in a broad-spectrum practice were enrolled. Exclusion criteria included patients of Asian descent, active anterior segment pathology, obvious lid alterations or deformities, strabismus more than 20Δ. A 20-μL drop of 2% fluorescein was instilled into the lower eyelid conjunctival sac. The complete length of the upper lid margin, in upward fixation (∼45°, with the eyes open), was examined for Marx's line. Results: Sixty-eight males and 131 females were enrolled. The age range was 18 to 80 years; mean age = 51.7 ± 14.3 years. Before eyelid eversion, Marx's line was visible in 99.0% of eyes and was visibly continuous for the entire eyelid margin length in 93.2% of eyes. Conclusions: Marx's line of the upper lid is visible in upgaze, without lid eversion, suggesting that is not the contact area for the upper lid wiping of the ocular surfaces in that position of gaze. Further research is required to determine the position and visibility of the line through all other lid positions during blinking. Copyright © Contact Lens Association of Ophthalmologists, Inc.


McMonnies C.W.,University of New South Wales | Korb D.R.,Korb Associates | Korb D.R.,Tear Science Inc. | Blackie C.A.,Korb Associates | Blackie C.A.,Tear Science Inc.
Contact Lens and Anterior Eye | Year: 2012

Purpose: To examine the role of elevated corneal temperature in the development of rubbing/massage-related corneal deformation and the possibility that warm compresses in the management of meibomian gland dysfunction or chalazion could contribute to such adverse responses. Methods: With reference to reports of corneal deformation associated with meibomian gland dysfunction, chalazion, dacryocystoceles and post-trabeculectomy, the mechanisms for increased corneal temperature due to ocular massage, especially when combined with warm compresses are examined. Results: Several mechanisms for rubbing/massage to elevate corneal temperature have been described, apart from the application of warm compresses or other forms of heat. Conclusions: Raised corneal temperature helps to explain corneal deformation which develops in association with rubbing or massage in conditions such as keratoconus, chalazion, post-trabeculectomy, post-laser assisted in situ keratomileusis, post-graft and dacryocystoceles. When combined with warm compresses or other methods of heat delivery to the eye, the elevation of corneal temperature appears to explain how meibomian gland dysfunction treatment involving warm compresses and massage could induce rubbing-related deformation. Patients whose management involves iatrogenic ocular massage appear to require screening for risk of corneal deformation. Risk may be increased for patients with a concurrent habit of rubbing their eyes abnormally in response to allergic itch for example. It appears to be possible to modify ocular massage techniques to reduce the risk of corneal deformation. Careful tutoring and follow-up using corneal topography appears to be required when massage is prescribed, especially when used in conjunction with heat application. © 2012 British Contact Lens Association.


Korb D.R.,Korb Associates | Korb D.R.,TearScience | Blackie C.A.,Korb Associates | Blackie C.A.,TearScience
Cornea | Year: 2010

A new and previously unpublished thermodynamic treatment device, which for the first time applies heat directly to both inner eyelid surfaces with a precision-controlled resistive heater while pulsating pressure is simultaneously applied to the outer eyelids using an inflatable air bladder, was used to restore meibomian gland functionality for a subject with severe evaporative dry eye. The subject, a 39-year-old white woman of light complexion with severe symptoms and corroborating objective signs of dry eye, had been unsuccessfully treated for 3 years by 7 practitioners. Using a new standardized meibomian gland expression device, a diagnosis of nonobvious meibomian gland dysfunction, where none of the approximately 24 meibomian glands of the right lower eyelid and 1 meibomian gland of the left lower eyelid were functional, was made. The patient underwent a single 12-minute treatment per eye with the treatment device. The treatment restored the functionality of 8 glands in each eye, doubled the fluorescein break-up time (FBUT) from 5 to 10 seconds, and decreased the symptom scores by approximately 80% for the entire follow-up period of 3 months. © 2010 by Lippincott Williams and Wilkins.


Korb D.R.,Korb Associates | Korb D.R.,TearScience | Blackie C.A.,Korb Associates | Blackie C.A.,TearScience
Eye and Contact Lens | Year: 2013

Objective: The aim of this study was to investigate whether a single case of meibomian gland dysfunction (MGD), with significant MG dropout resulting in evaporative dry eye, could be effectively treated with the LipiFlow (a new Food and Drug Administration-approved thermodynamic pulsatile treatment). Materials and Methods: A 39-year-old white woman experienced severe dry eye symptoms because of MGD with considerable MG dropout resulting in evaporative dry eye. Standardized diagnostic MG expression and meibography led to the tentative diagnosis of nonobvious MGD (only 1 functional MG on each lower lid) and MG dropout (∼50% of the lower lid MGs were missing with the remaining MGs being severely truncated). The patient underwent a single 12-min LipiFlow treatment per eye and returned for follow-up at 1 and 7 months posttreatment. RESULTS: The LipiFlow treatment increased the number of functional lower lid MGs from 1 to 5 glands OD and 1 to 7 glands OS at 1 month with slight regression at 7 months (4 OD and 4 OS); increased fluorescein break-up time from 4 to 7 sec OD and 4 to 9 sec OS at both 1 and 7 months; and decreased symptom scores by approximately 50% at 1 month and approximately 75% at 7 months. Conclusions: These results demonstrate the effectiveness of the LipiFlow in restoring MG function and improving ocular comfort even in this particular case of significant MG dropout and MG truncation. © 2013 Contact Lens Association of Ophthalmologists.


Knop E.,Charité - Medical University of Berlin | Korb D.R.,Korb Associates | Blackie C.A.,Korb Associates | Knop N.,Hannover Medical School
Developments in Ophthalmology | Year: 2010

Purpose: The structure of the lid margin is insufficiently understood and defined, although it is of obvious importance in ocular surface integrity. Methods: The structure and function of the different zones of the lid margin are explained with a focus on dry eye disease. Results: The posterior lid margin, which is of particular significance for the integrity of the ocular surface, includes the meibomian glands that open within the cornified epidermis. Their obstructive dysfunction is a main cause of dry eye disease. The orifice is followed by the mucocutaneous junction, which extends from the abrupt termination of the epidermis to the crest of the inner lid border. The physiological vital stainable line of Marx represents its surface, and can be used e.g. as a diagnostic tool for the location and functionality of the meibomian gland orifices and lacrimal puncta. The marginal conjunctiva starts at the crest of the inner lid border and forms a thickened epithelial cushion. This is the point closest to the globe, and represents the zone that wipes the bulbar surface and distributes the thin preocular tear film. It is hence termed the 'lid wiper' and pathological alterations that result in a vital staining are a sensitive early indicator of dry eye disease. Conclusions: The margin of the eyelid is an important but currently underestimated structure in the maintenance of the preocular tear film and of the utmost importance for the preservation of ocular surface integrity and in the development of dry eye disease. © 2010 S. Karger AG, Basel.


Knop E.,Charité - Medical University of Berlin | Knop N.,Charité - Medical University of Berlin | Zhivov A.,University of Rostock | Kraak R.,University of Rostock | And 4 more authors.
Journal of Anatomy | Year: 2011

The inner border of the eyelid margin is critically important for ocular surface integrity because it guarantees the thin spread of the tear film. Its exact morphology in the human is still insufficiently known. The histology in serial sections of upper and lower lid margins in whole-mount specimens from 10 human body donors was compared to in vivo confocal microscopy of eight eyes with a Heidelberg retina-tomograph (HRT II) and attached Rostock cornea module. Behind the posterior margin of the Meibomian orifices, the cornified epidermis stopped abruptly and was replaced by a continuous layer of para-keratinized (pk) cells followed by discontinuous pk cells. The pk cells covered the muco-cutaneous junction (MCJ), the surface of which corresponded to the line of Marx (0.2-0.3mm wide). Then a stratified epithelium with a conjunctival structure of cuboidal cells, some pk cells, and goblet cells formed an epithelial elevation of typically about 100μm initial thickness (lid wiper). This continued for 0.3-1.5mm and formed a slope. The MCJ and lid wiper extended all along the lid margin from nasal to temporal positions in the upper and lower lids. Details of the epithelium and connective tissue were also detectable using the Rostock cornea module. The human inner lid border has distinct zones. Due to its location and morphology, the epithelial lip of the lid wiper appears a suitable structure to spread the tear film and is distinct from the MCJ/line of Marx. Better knowledge of the lid margin appears important for understanding dry eye disease and its morphology can be analysed clinically by in vivo confocal microscopy. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.


Korb D.R.,Korb Associates | Herman J.P.,Pittsfield Eye Associates | Blackie C.A.,Korb Associates | Scaffidi R.C.,Tufts Medical School | And 4 more authors.
Cornea | Year: 2010

Purpose: The purpose of this study was to investigate the prevalence of lid wiper epitheliopathy (LWE) in patients diagnosed with dry eye disease (DED). Methods: Patients were recruited for two groups. Inclusion criteria for the DED group (n = 50) was: a score greater than 10 with the Standard Patient Evaluation of Eye Dryness questionnaire, fluorescein break-up time 5 seconds or less, corneal and conjunctival staining with fluorescein, lissamine green Grade 1 or greater (scale 0-3), and Schirmer test with anesthesia 5 mm or less. For the asymptomatic group (n = 50), inclusion criteria were: no dry eye symptoms, fluorescein break-up time 10 seconds or greater, no corneal or conjunctival staining, and Schirmer test 10 mm or greater. Sequential instillations (n = 2, 5 minutes apart) of a mixture of 2% fluorescein and 1% lissamine green solution were used to stain the lid wipers of all patients. LWE was graded (scale 0-3) using the horizontal lid length and the average sagittal lid widths of the stained wiper. Results: In symptomatic patients, 88% had LWE, of which 22% was Grade 1, 46% Grade 2, and 20% Grade 3. In asymptomatic patients, 16% had LWE, of which 14% was Grade 1, 2% was Grade 2, and 0% Grade 3. The difference in prevalence of lid wiper staining between groups was significant (P<0.0001). Conclusions: The prevalence of LWE was six times greater for the DED group and the prevalence of LWE Grade 2 or greater was 16 times greater for the DED group than for the control group. These data further establish LWE as a diagnostic sign of dry eye disease. © 2010 Lippincott Williams & Wilkins.


Knop N.,Charité - Medical University of Berlin | Korb D.R.,Korb Associates | Korb D.R.,TearScience | Korb D.R.,University of California at Berkeley | And 4 more authors.
Cornea | Year: 2012

Purpose: The conjunctival side of the upper and lower inner eyelid borders, termed the lid wiper, has a thickened epithelial lip for apposition to the globe, assumed to distribute the preocular tear film. The human lid wiper structure and its goblet cells are investigated. Methods: Conjunctival whole mounts, including lid margins from 17 eyes of human body donors, were investigated by routine histology and semithin plastic sections, using histology, histochemistry, and immunohistochemistry. Results: In routine histology, the conjunctival lid wiper epithelium regularly showed goblet cells, single and in clusters, at the luminal surface and also deep within the epithelium without apparent surface contact. Semithin sections revealed that the deep goblet cells were often connected to cryptal epithelial infoldings that opened to the surface, hence making their mucins available at the surface. The goblet cells produced mucins of neutral (periodic acid-Schiff) and acidic (Alcian blue) type and stained positive for the gel-forming mucin MUC5AC. Surprisingly, MUC5AC-negative goblet cells were also observed in the lid wiper. Conclusions: Contrary to conventional assumptions, the lid wiper is part of the conjunctiva. It contains previously undescribed goblet cell crypts deep in the epithelium, suitable as an internal lubrication system for reduction of friction between the lid margin and the globe. This provides the first evidence of the morphological basis for the hydrodynamic type of lubrication and a more conclusive understanding of lid-margin lubrication and tear film distribution. It is another strong indication that the lid wiper is that area in apposition with the globe for distributing the thin preocular tear film during the blink. Copyright © 2012 by Lippincott Williams & Wilkins.


Blackie C.A.,Korb Associates | Blackie C.A.,TearScience | Korb D.R.,Korb Associates | Korb D.R.,TearScience
Cornea | Year: 2010

Purpose: To investigate the diurnal secretory characteristics of individual meibomian glands (MGs). Methods: Ten subjects (4 females and 6 males) with healthy eyelid appearance and without dry eye symptoms were recruited (mean age = 23.8 ± 1.8 years). Both right and left lower eyelids were marked in 3 places to locate 5 consecutive MGs in each third (temporal, central, and nasal) of the lower eyelid. A total of 15 MGs per eye were diagnostically expressed for 10 seconds on both right and left lower eyelids every 3 hours for 4 consecutive measurements over a 9-hour period. Results: Thirty-four percent of all tested MGs yielded liquid secretion at all measurements. Sixty-nine percent of the tested nasal MGs yielded liquid secretion at all measurements in contrast to 31% of the central MGs and only 22% of the temporal MGs. The mean numbers of MGs secreting liquid oil were significantly higher in the nasal section relative to the central and temporal sections at all measurements (p < 0.001, all measurements). Conclusions: (1) A single MG is capable of secreting oil on demand over the course of a working day (∼9 hours); (2) nasal MGs were the most likely to secrete upon demand over the course of day compared with the temporal and to a lesser degree the central MGs; and (3) secretory characteristics of individual MGs examined as a function of their location in the lower eyelid does not change diurnally. © 2009 by Lippincott Williams & Wilkins.


Korb D.R.,Korb Associates | Korb D.R.,TearScience | Blackie C.A.,Korb Associates | Blackie C.A.,TearScience
Optometry and Vision Science | Year: 2015

The clinical perspective that dry eye is, at best, an incomplete diagnosis and the benefit of an etiology-based approach to dry eye are presented. To provide context for this perspective, the historical and current definition of dry eye is reviewed. The paradigm shift introduced by the Meibomian Gland Dysfunction (MGD) Workshop, that MGD is likely the leading cause of dry eye, is discussed in combination with the advancements in the diagnosis and treatment of MGD. To facilitate discussion on the benefit of an etiology-based approach, a retrospective observational analysis was performed on deidentified data from eligible, fully consented, refractory dry eye patients, where conventional sequelae-based dry eye treatment had failed. In this refractory population, the diagnosis of MGD, which directed treatment to evacuating gland obstructions and rehabilitating gland function, was successful. The clinical perspective that "dry eye" is the wrong diagnosis for millions is provocative. However, the MGD-first approach has the potential to revolutionize the timing of diagnosis and the choice of frontline therapy in most patients with dry eye. Additionally, the ability to screen for MGD in its earliest stages, during routine care, expands the scope of clinical practice to include early intervention. For most patients, we are no longer constrained to delay diagnosis until the tear film has decompensated and the cascade of inflammation has ensued. We do not have to wait for our patients to tell us there is a problem. © 2015 American Academy of Optometry.

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