The aim of the DEWS Definition and Classification Subcommittee was to provide a contemporary definition of dry eye disease, supported within a comprehensive classification framework. A new definition of dry eye was developed to reflect current understanding of the disease, and the committee recommended a three-part classification system. The first part is etiopathogenic and illustrates the multiple causes of dry eye. The second is mechanistic and shows how each cause of dry eye may act through a common pathway. It is stressed that any form of dry eye can interact with and exacerbate other forms of dry eye, as part of a vicious circle. Finally, a scheme is presented, based on the severity of the dry eye disease, which is expected to provide a rational basis for therapy. These guidelines are not intended to override the clinical assessment and judgment of an expert clinician in individual cases, but they should prove helpful in the conduct of clinical practice and research.

The definition and classification of dry eye disease: Report of the definition and classification subcommittee of the international Dry Eye WorkShop (2007)

Fibroblasts can condense a hydrated collagen lattice to a tissue-like structure 1/28th the area of the starting gel in 24 hr. The rate of the process can be regulated by varying the protein content of the lattice, the cell number, or the con- centration of an inhibitor such as Colcemid. Fibroblasts of high population doubling level propagated in vitro, which have left the cell cycle, can carry out the contraction at least as efficiently as cycling cells. The potential uses of the system as an immu- nologically tolerated "tissue" for wound hea ing and as a model for studying fibroblast function are discussed.

Production of a tissue-like structure by contraction of collagen lattices by human fibroblasts of different proliferative

The goals of the TFOS DEWS II Definition and Classification Subcommittee were to create an evidence-based definition and a contemporary classification system for dry eye disease (DED). The new definition recognizes the multifactorial nature of dry eye as a disease where loss of homeostasis of the tear film is the central pathophysiological concept. Ocular symptoms, as a broader term that encompasses reports of discomfort or visual disturbance, feature in the definition and the key etiologies of tear film instability, hyperosmolarity, and ocular surface inflammation and damage were determined to be important for inclusion in the definition. In the light of new data, neurosensory abnormalities were also included in the definition for the first time. In the classification of DED, recent evidence supports a scheme based on the pathophysiology where aqueous deficient and evaporative dry eye exist as a continuum, such that elements of each are considered in diagnosis and management. Central to the scheme is a positive diagnosis of DED with signs and symptoms, and this is directed towards management to restore homeostasis. The scheme also allows consideration of various related manifestations, such as non-obvious disease involving ocular surface signs without related symptoms, including neurotrophic conditions where dysfunctional sensation exists, and cases where symptoms exist without demonstrable ocular surface signs, including neuropathic pain. This approach is not intended to override clinical assessment and judgment but should prove helpful in guiding clinical management and research.

TFOS DEWS II Definition and Classification Report

IOVS MS 11-7777 (Article 2207) Proofs Available _______________________ Dear Author: The proofs of your article above are available for your review. Please download the file located at this URLaddress: http://rapidproof.cadmus.com/RapidProof/retrieval/index.jsp Login: [your e-mail address]Password: 99S4UntgTcU9 You will need to have Adobe Acrobat Reader software to read this file. This is free software and is availablefor user downloading at http://www.adobe.com/products/acrobat/readstep.html. If you experience technical problems, please contact Tracey Ritchey(e-mail: ritcheyt@cadmus.com; phone: 717-721-2646) This file contains: -- Instructions to Author-- Adobe Acrobat Comments and Notes Instructions-- Publication Fees and Reprint Order Form-- Page Proofs for your article, table of contents precis blurb, and author queries - containing 5 pages Please insert your comments electronically (instructions enclosed), or print the PDF proofs and add yourcomments manually. Follow the enclosed instructions for emailing, faxing, or mailing your corrections.Return all materials within 48 hours (two business days) to assure quick publication of your article. NOTE: Effective with the January 2010 issue IOVS will be available online only. No printed issues will beproduced. Printed reprints may still be ordered using the file provided. If you have any questions regarding your article, please contact me. ALWAYS INCLUDE YOURARTICLE NO. (IOVS MS 11-7777) WITH ALL CORRESPONDENCE. Cathy FreyTel: 717-721-2616Fax: 717-738-9479 or 717-738-9478freyc@cadmus.com

/pdf/investigative-ophthalmology-and-visual-science-2azo1n1ewx.pdf

Investigative Ophthalmology and Visual Science

http://sun-lab.med.nyu.edu/files_private/sun-lab/attachments/1989.Cell.Cotsarelis-s.pdf

Existence of slow-cycling limbal epithelial basal cells that can be preferentially stimulated to proliferate: implications on epithelial stem cells.

Limbal Autograft Transplantation for Ocular Surface Disorders

Objective To examine whether amniotic membrane transplantation (AMT), in preparing the perilimbal stroma, enhances the success of allograft limbal transplantation (ALT). Methods Thirty-one eyes of 26 consecutive patients had cytologically proven limbal deficiency resulting from chemical burns (14 eyes); Stevens-Johnson syndrome, toxic epidermal necrolysis, or pseudopemphigoid (5 eyes); contact lens–induced keratopathy (3 eyes); aniridia (3 eyes); multiple surgical procedures (2 eyes); atopy (2 eyes); or an unknown cause (2 eyes). Based on the severity of limbal deficiency, group A (mild), comprising 10 eyes, received AMT alone; group B (moderate), comprising 7 eyes, received AMT and ALT; and group C (severe), comprising 14 eyes, received AMT, ALT, and penetrating keratoplasty. All patients except those in group A received continuous oral cyclosporine. Results Except for the 2 eyes with atopy, all amniotic membrane–covered surfaces showed rapid epithelialization (in 2 to 4 weeks) and reduced inflammation, vascularization, and scarring, and the surfaces became smooth and wettable. For the mean follow-up period of 15.4 months, 25 (83%) of 30 eyes showed visual improvement, consisting of 6 or more lines (13 eyes), 4 to 5 lines (6 eyes), or 1 to 3 lines (6 eyes). Visual improvement decreased with the severity of limbal deficiency from 8 (100%) of 8 eyes in group A to 5 (71%) of 7 eyes in group B and 11 (79%) of 14 eyes in group C. In group C, corneal graft rejection occurred in 9 (64%) of 14 eyes, and reversible early limbal allograft rejection was noted in 3 (14%) of 21 eyes of groups B and C. Conclusions For partial limbal deficiency with superficial involvement, AMT alone is sufficient and hence superior to ALT because there is no need to administer cyclosporine. For total limbal deficiency, additional ALT is needed, and AMT helps reconstruct the perilimbal stroma, with reduced inflammation and vascularization, which collectively may enhance the success of ALT.

https://jamanetwork.com/journals/jamaophthalmology/articlepdf/262115/ecs7741.pdf

Amniotic Membrane Transplantation With or Without Limbal Allografts for Corneal Surface Reconstruction in Patients With Limbal Stem Cell Deficiency

After n-heptanol removal of the total corneal epithelium and a limbal lamellar keratectomy, 23 rabbit eyes developed features of limbal stem cell deficiency including conjunctival epithelial ingrowth, vascularization and chronic inflammation. One month later, 10 control eyes received a total keratec

Transplantation of Preserved Human Amniotic Membrane for Surface Reconstruction in Severely Damaged Rabbit Corneas

Amniotic membrane transplantation for persistent epithelial defects with ulceration.

Cumulative reported evidence indicates that some fraction of limbal basal epithelial cells are the stem cells for corneal epithelial cell proliferation and differentiation. Limbal epithelium is therefore crucial in maintaining the cell mass of corneal epithelium under normal conditions and plays an important role in corneal epithelial wound healing. Deficiency or absence of limbal stem cells explains well the pathogenesis of several ocular surface disorders characterised by defective conjunctival transdifferentiation or conjunctivalisation of cornea. This paper reviews and updates the basic concept of stem cells, the reported findings of limbal stem cells for corneal epithelium, and their therapeutic applications. Through this review, one hopes to gain a more complete understanding and increase proficiency in treating these diseases.

/pdf/concept-and-application-of-limbal-stem-cells-55b3s4s830.pdf

Scheffer C.G. Tseng

Papers

Limbal Autograft Transplantation for Ocular Surface Disorders

Amniotic Membrane Transplantation With or Without Limbal Allografts for Corneal Surface Reconstruction in Patients With Limbal Stem Cell Deficiency

Transplantation of Preserved Human Amniotic Membrane for Surface Reconstruction in Severely Damaged Rabbit Corneas

Amniotic membrane transplantation for persistent epithelial defects with ulceration.

Concept and application of limbal stem cells.