Study: Ptosis surgery and dry eye

This study claims that incidence of dry eye was surprisingly low after this particular form of surgery to correct mild to moderate ptosis. I would be curious to know how they evaluated dryness - clinical signs (and if so which), patient symptoms, or both. - Particularly given the timeframe of all these patients' cases, 1988-1996, when there was not nearly as much attention paid to dry eye as there is today.

Fasanella-Servat procedure: indications, efficacy, and complications.
Pang NK, Newsom RW, Oestreicher JH, Chung HT, Harvey JT.
Can J Ophthalmol. 2008 Feb;43(1):84-8

Background: The Fasanella-Servat procedure is used for the repair of mild to moderate ptosis. The purpose of this study was to determine the efficacy of the Fasanella-Servat procedure for the repair of several forms of ptosis. Methods: The authors retrospectively reviewed 169 charts of 2 surgeons from 1988 to 1996. All patients had undergone a Fasanella-Servat procedure for ptosis. Patients with less than a 1-month follow-up were excluded, leaving 153 eyelids of 144 patients. Surgical success was defined as lid symmetry within 0.5 mm or correction of eyelid contour abnormality from previous surgery or trauma. Results: Ptosis was classified as involutional, occurring after intraocular surgery, congenital, due to Horner's syndrome present after levator surgery, and myogenic/other. With a mean follow-up of 7 months, success was achieved in 89.5% of cases (137/153). Among subgroups, success was highest at 100% in Horner's syndrome (8/8) and post-levator surgery (11/11), and lowest in congenital ptosis at 76.4% (13/18). Postoperative problems included dry eye symptoms (6/144 patients), contour abnormalities in 12 lids, and dermatochalasis in 10 lids. Interpretation: The Fasanella-Servat operation is effective for mild to moderate ptosis from a variety of causes and for contour abnormality correction in patients with little or no ptosis. Despite the long-held belief that excision of the accessory lacrimal glands of Wolfring leads to dry eye symptoms, our study found this to be the exception. This procedure has the advantage of high reliability when reasonable preoperative criteria are applied and is minimally invasive.

Newsblurb: From ASCRS, on blepharitis/MGD

Excerpt from an Eyeworld email blast reporting on the ASCRS meeting in Hawaii

Discussing the classification of blepharitis, James McCulley, M.D., noted four basic types: staphylococcal, seborrheic, primary meibomitis (MKC), and meibomian gland dysfunction. The pathophysiology of chronic blepharitis can be attributed to both biochemical abnormalities of the meibum as well as bacterial lipolytic exoenzymes, but not to a single bacterium. Dr. McCulley stressed that therapy should not be used to cure the disease but to provide relief and control. Mechanical and hygienic measures include hot compresses, massage, and lid scrubs. Recommended topical antibiotic treatments include bacitracin, fluoroquinolones, aminoglycides, and tetracyclines. Systemic antibiotics are only indicated in severe cases of acute bacterial blepharitis, secondary meibomianitis, and MKC. Recommended systemic antibiotics include tetracycline analogues (including minocycline), and macrolides.

Nothing new here that I can see but I think that this is a nice overview for patients and doctors alike. I really appreciate the acknowledgment of the importance of compresses, massages and scrubs in these lid diseases. I was also relieved to see Restasis NOT on the list of treatments. I've been hearing rumors of it being promoted for MGD treatment but to date I have seen no medical literature demonstrating efficacy for such an indication.

Rebecca's journal: A visit to Barleans

Yesterday I played hooky.

It was a breathtakingly beautiful day. I drove up to Kingston, took the ferry across the Sound, and drove from Edmonds up to Ferndale, which is not far from the Canadian border. My destination was the Barleans farm in Ferndale where the celebrated flaxseed oils are made.

The Barlean family lives on the property and before touring their business facilities I was treated to a lovely lunch of fresh salmon, enjoyed in the company of three generations of Barleans plus my wonderful sales rep Patti. As some of you fans of their products may have read. Bruce Barlean is a man of many trades and was a fisherman before getting the oil business going. They still run a famous fish market right there on site.

It was great fun to see their operation and learn about its history... and was a very interesting and informative visit. And when I finally got back in my car, laden with all kinds of samples and a couple of books, and headed east towards the freeway, there was Mount Baker right smack in front of me, closer than I've been to it in at least 20 years. Absolutely stunning.

Other than temporarily releasing myself from the ball and chain, meeting some nice hospitable people and loading up with loot, the more serious purpose of my trip was to get started on one of my recent resolutions: To let go of my longstanding willful ignorance of the dreaded "dry eye and nutritional supplements" topic and make something resembling an honest attempt to understand enough of it to form something resembling an actual opinion, without, hopefully, having to learn any more actual Information than absolutely necessary.

The fact is, I'm tired of squirming, mumbling incoherently and rapidly changing the subject when asked for advice about fish oil, flaxseed oil, EPA/DHA, Biotears, Theratears Nutrition or whatever. I have developed the bad habit of ignoring the whole subject simply because I despise the extremes, from the enormous generic bottles of Fish Oil (goodness knows what mutated species of farmed fish that crud comes from) to the elite "black-box" formulae on the market all claiming to be THE only formula scientifically proven to work for dry eye.

So, I'm going to attempt to grapple with dry eye and essential fatty acids, with the help of a few friends. Logically, there must be good information to be had somewhere in this mess, and surely with a little effort I can pick up enough of it to not hurt myself and perhaps even to equip myself to say something slightly more intelligent than my usual reluctant "Well... they can't hurt, they might help, and everyone agrees they're good for general health."

As I learn, you'll no doubt be seeing some changes to what I offer in The Dry Eye Shop as a result.

Up till this point, the Omega 3 EFAs section of the shop has been markedly different than the other sections of the shop: All others are based on my and others' actual experiences with dry eye products plus my personal opinions about what kinds of products are critically important to dry eye patients. Omega 3s were more of a reluctant nod to the fact that everyone agrees we "ought" to take them. I sold - and, mind you, faithfully used and always liked - Dry Vites for quite some time. When that got too expensive for my taste, I just went out and looked for the best company I could find that offered multiple types of Omega 3s at what seemed to be a reasonable price. I fell in love with Barleans and am convinced their quality and service are tops, so I stuck with them. Visiting their facility yesterday confirmed all that and also helped motivate me to stick with my resolution to dig further.

Wish me luck, and if you have any good pointers to send my way, feel free. Try to stick with words of three syllables or less though. :-)

Industry news: Lacriserts website / distributor info

No, Lacriserts have NOT gone away, although they've been quiet for so long that it isn't any wonder people think so. As noted in a previous posting, Merck sold this product to Aton Pharma awhile back.

Yesterday Aton put out a press release and announced the launch of their new website, Lacrisert.com.

If you're a past Lacrisert user and are having trouble finding them or have been told they are no longer available, please see Aton's page with distributor information... you may want to print off the page and take it to your pharmacist:

If you're a patient who has never heard of Lacriserts, they're basically hypromellose (the stuff some artificial tears are made of) put into a little pellet that gets shoved down into your lower lid for a 'slow release' effect during the day. They are sold only by prescription. They have never been very popular but they are one of those dry eye products that has a loyal albeit very small following. Since that is the case, I'm pleased to see that they are being kept on the market and promoted rather than falling victim to the "If we can't make a big enough line item on our financials from it, we won't bother producing it" syndrome that dominates most pharmaceuticals.

If you're a doctor and thought Lacriserts were off the market, please note that they are still around and you can get prescribing info at this link.

If you're a patient and you're now mad at your doctor for erroneously telling you Lacriserts can't be had anymore, go easy on the poor guy/gal - it's impossible to keep up with all this stuff. Instead, how about politely suggesting to him/her that they subscribe to my free Monday Dry Eye Bulletins so that they can keep up with new dry eye products more easily. They can call 1-877-693-7939 x2.

Study: A veritable rainbow of corneal staining

I've been wondering when we'd start seeing more studies on staining methods. Seems like I've read a ton of little newspaper snippets over the last several months about lissamine green from some kind of press release out of UTSW. Anyway, this study is basically mixing and matching different dyes for different types of staining to see if they can make the process simpler without losing any diagnostic accuracy.

An evaluation of the efficacy of fluorescein, rose bengal, lissamine green, and a new dye mixture for ocular surface staining.
Korb DR, Herman JP, Finnemore VM, Exford JM, Blackie CA
Eye Contact Lens. 2008 Jan;34(1):61-4

PURPOSE.: Sodium fluorescein is considered the premier dye for corneal staining and, similarly, rose bengal (RB) for conjunctival staining. A mixture of 1% fluorescein and 1% rose bengal has been reported as advantageous in daily practice. Mixtures of lissamine green with other ocular stains have not been reported. The purposes of this study were to review the clinical staining characteristics of fluorescein, rose bengal, and lissamine green in controlled dose and concentration and determine whether optimal staining of the cornea and bulbar conjunctiva are possible by using dye mixtures.
METHODS.: Sixteen 10-muL solutions of fluorescein, rose bengal, lissamine green, and their mixtures were evaluated. Fourteen subjects with a diagnosis of dry eye were tested for staining with various combinations of the dyes. Examination of staining was made by using standard clinical practices.
RESULTS.: A mixture of 2% fluorescein and 1% rose bengal was the most efficacious staining mixture for the cornea and conjunctiva, but moderate to marked discomfort was reported. The mixture of 2% fluorescein and 1% lissamine green did not result in discomfort and provided optimal corneal and conjunctival staining with only slightly less efficacy than 2% fluorescein and 1% rose bengal; 2% and 3% lissamine green produced burning and discomfort. The fluorescent characteristics of fluorescein were not significantly altered by the addition of 1% lissamine green. The preferred mixture for simultaneous and efficacious staining of the cornea and conjunctiva without an adverse sensation was 2% fluorescein and 1% lissamine green.
CONCLUSIONS.: A mixture of 2% fluorescein and 1% lissamine green offers excellent simultaneous corneal and bulbar conjunctival staining and could replace the use of individual dyes for ocular staining and contact lens practice.

Study: Restasis and contacts

In this interesting study, completed in Birmingham (as opposed to, er, Irvine), contact lens wearers with dry eye issues experienced NO benefit to signs OR symptoms of dry eye after taking Restasis for three months. Not one measly little parameter showed any statistically significant improvement.

The abstract does not tell us how many participants there were, and the authors are conscientious about acknowledging that the "small sample size" may have affected the results. Not that they ought to feel obliged to be apologetic about not reporting better results! But seriously, it is not easy to go against the grain of published literature, which is overwhelmingly pro Restasis.

While this study is "about" contact lens wearers, note that it was NOT attempting to measure their contact lens comfort. It was measuring their dry eye signs and symptoms. It kind of struck me as a subtle back door way of really saying, "Here's a broad spectrum group of people for whom Restasis did nothing". The more obvious message of the study, of course, is that all those physicians who refuse to stray from the path of pharmacological treatment for ocular surface disease even where other treatment is clearly indicated by lid margin disease, nocturnal lagophthalmos, BAK toxicity or what have you, not to mention chronic contact lens overwear, should not look to Restasis as the magic bullet for contact lens tolerance problems. Not that I hold out hope of that message taking hold, mind you. After all, this is an industry that indirectly touts laser refractive surgeries as a solution for contact lens intolerance. Sigh.

Efficacy of Cyclosporine 0.05% Ophthalmic Emulsion in Contact Lens Wearers With Dry Eyes.
Willen CM, McGwin G, Liu B, Owsley C, Rosenstiel C
Eye Contact Lens. 2008 Jan;34(1):43-45

PURPOSE.: To assess the efficacy of cyclosporine 0.05% ophthalmic emulsion (Restasis; Allergan, Inc., Irvine, CA) in the treatment of contact lens wearers with dry eyes.

METHODS.: Contact lens wearers citing dry eye problems were identified through chart review. Participants were randomly assigned to a treatment group, receiving vials of cyclosporine 0.05% ophthalmic emulsion to use twice daily, or a placebo group, receiving vials of rewetting drops (Refresh Preservative Free Artificial Tears; Allergan, Inc.) to use twice daily. Corneal staining, tear film breakup time, and Schirmer test results were documented at baseline and after 3 months. Participants also completed questionnaires, the Ocular Surface Disease Index, and the National Eye Institute Refractive Error Quality of Life Instrument at baseline and after 3 months.

RESULTS.: For all parameters, including objective findings and subjective reporting of symptoms, there was no statistically significant difference between the treatment and placebo groups.

CONCLUSIONS.: This study did not detect a beneficial effect in using cyclosporine 0.05% ophthalmic emulsion over rewetting drops for contact lens wearers. This may be attributable to the small sample size. It is also possible that the mechanism of the dry eye state in contact lens wearers may be different from that of other dry eye states and thus make cyclosporine 0.05% ophthalmic emulsion an ineffective treatment.

Study: 02Optix lenses

To be taken with just as large a clump of salt as any manufacturer-funded study, but for those interested in any claims of dry eye friendly contact lenses, read on.

Performance of Lotrafilcon B silicone hydrogel contact lenses in experienced low-Dk/t daily lens wearers
Dillehay SM, Miller MB
Eye Contact Lens. 2007 Nov;33(6 Pt 1):272-7

PURPOSE: The silicone hydrogel lens O2OPTIX with a Dk/t of 138 (at -3.00 diopters [D]) was evaluated and compared with patients' habitual low-Dk/t lenses.
METHODS: This large, multisite (United States and Canada), single-masked study enrolled experienced daily-wear, low-Dk/t, 2-week replacement soft contact lens wearers. Subjects underwent baseline evaluations and were fitted with O2OPTIX lenses for a 2-week period. After 2 weeks, subjects returned for assessment versus their habitual lenses.
RESULTS: Data for 760 subjects were analyzed. The overall average habitual contact lens power was -3.13 D, and the average O2OPTIX lens power was -3.22 D. Biomicroscopy evaluations showed improvements in signs related to corneal health with O2OPTIX. Conjunctival and limbal redness, corneal neovascularization, corneal edema, and corneal and conjunctival staining all decreased significantly from baseline. O2OPTIX lenses performed better than habitual lenses in terms of comfort, symptoms, and overall preference. When wearing O2OPTIX lenses, significantly fewer subjects reported problems compared to their habitual lenses, including uncomfortable lens wear (-20.3%), redness (-44.5%), dryness during the day (-40.2%), and dryness at the end of the day (-34.4%); 47.9% reported that they could wear O2OPTIX lenses longer than their habitual lenses. At the end of study, among those with a preference, a significantly greater proportion of patients (60.3%) preferred O2OPTIX lenses to their habitual lenses.
CONCLUSIONS: Daily wear of O2OPTIX lenses resulted in improvements in corneal signs of health and patient symptoms and provided excellent vision and comfort. O2OPTIX lenses were preferred by subjects over their habitual lenses.

Case report: From Osteopoikilosis to RA to dry eye

Just a tiny case report in a rheumatology journal but I thought it was an interesting reminder of the challenging detective work occasionally needed to track down the source of dry eye symptoms.

Osteopoikilosis in a patient with rheumatoid arthritis complicated with dry eyes.
Ureten K
Rheumatol Int. 2007 Sep;27(11):1079-82. Epub 2007 Mar 29

Osteopoikilosis is an uncommon sclerosing bone dysplasia of unknown etiology. It is usually detected as a coincidental finding at radiographic examination. Mild joint pain and swelling may be seen in 15-20% of cases. Osteopoikilosis is rarely associated with rheumatoid arthritis. In this case report a young man with osteopoikilosis who was diagnosed as having rheumatoid arthritis complicated with dry eyes is presented. Although patients with osteopoikilosis may have articular symptoms, those patients should be carefully examined for a possible association with a rheumatic condition

Study: Pre-operative risk factors for post LASIK dry eye

To those of you with post LASIK dry eye, your initial response will probably be "Well, duh! Dry before surgery = drier / higher risk afterwards. Oh and by the way, why didn't they run those tests on ME before surgery?" Fair enough, it's not exactly a newsworthy study. However, there are one or two points of interest. Check out the one I highlighted in the abstract, for example....

On the other hand, what I really want to know is, why didn't they do an anesthetized schirmer - or if they did, why not report on it? (Hard to believe it's because it correlated with nothing at all.) LASIK surgeons do not normally relish operating on the likes of Sjogrens patients, and most of us lasikees were not seriously aqueous deficient before lasik. MGD red flags is what we had.

Oh - and another point of mild interest. Those of you who gripe about being told repeatedly that you're still healing may be interested to note that these authors consider dry at 9 months to be "chronic" dryness. Sounds discouraging on the face of it but when you put this in the context of all the other studies showing nerve regrowth for far longer periods, I would not take it too seriously.

Preoperative characteristics and a potential mechanism of chronic dry eye after LASIK.
Konomi K, Chen LL, Tarko RS, Scally A, Schaumberg DA, Azar D, Dartt DA
Invest Ophthalmol Vis Sci. 2008 Jan;49(1):168-74

PURPOSE: To determine whether measurable preoperative characteristics predispose patients to chronic dry eye after laser in situ keratomileusis (LASIK).

METHODS: The study consisted of 24 eyes of 24 patients who underwent LASIK. Tear breakup time, Schirmer testing with and without anesthesia, rose bengal staining, central corneal sensitivity, nucleus-to-cytoplasmic ratio, and goblet cell density were evaluated 2 weeks before and 1 week, 3 months, and 9 months after surgery. Patients were classified into two outcome groups, the nondry-eye group (NDEG) and the chronic dry-eye group (CDEG), on the basis of dry eye status 9 months after surgery. The authors tested whether preoperative values of each parameter were associated with the development of chronic dry eye.

RESULTS: All parameters, except rose bengal staining, deteriorated significantly after surgery but returned to preoperative levels within 3 to 9 months. The CDEG had significantly lower preoperative Schirmer test values with and without anesthesia and were delayed in recovery after surgery in goblet cell density, rose bengal staining, Schirmer test values without anesthesia, and tear breakup time. Results of preoperative Schirmer tests without anesthesia positively correlated with tear breakup time 9 months after surgery.

CONCLUSIONS: Preoperative tear volume may affect recovery of the ocular surface after LASIK and may increase the risk for chronic dry eye

Study: More on mucins

Well, I wish I could wave a magic wand over this to translate it to normal English. On the other hand, those of you who, like me, are interested in the mucin aspects of dry eye mostly know so much more about it than I do that I really don't have to bother :-) For those who don't know why they should care, mucin is the sticky substance on the surface of the cornea that makes tears adhere properly to the surface of the eye. With or without a good tear production or tear quality, the state of your mucin "layer" can make a big difference to your comfort and ocular surface health. That is why this area of research is so critical in the long-term.

Antiadhesive Character of Mucin O-glycans at the Apical Surface of Corneal Epithelial Cells.
Sumiyoshi M, Ricciuto J, Tisdale A, Gipson IK, Mantelli F, Argüeso P.
Invest Ophthalmol Vis Sci. 2008 Jan;49(1):197-203.

PURPOSE: Prolonged contact of opposite mucosal surfaces, which occurs on the ocular surface, oral cavity, reproductive tract, and gut, requires a specialized apical cell surface that prevents adhesion. The purpose of this study was to evaluate the contribution of mucin O-glycans to the antiadhesive character of human corneal-limbal epithelial (HCLE) cells.
METHODS: Mucin O-glycan biosynthesis in HCLE cells was disrupted by metabolic interference with benzyl-alpha-GalNAc. The cell surface mucin MUC16 and its carbohydrate epitope H185 were detected by immunofluorescence and Western blot. HCLE cell surface features were assessed by field emission scanning electron microscopy. Cell-cell adhesion assays were performed under static conditions and in a parallel plate laminar flow chamber.
RESULTS: Benzyl-alpha-GalNAc disrupted the biosynthesis of O-glycans without affecting apomucin biosynthesis or cell surface morphology. Static adhesion assays showed that the apical surface of differentiated HCLE cells expressing MUC16 and H185 was more antiadhesive than undifferentiated HCLE cells, which lacked MUC16. Abrogation of mucin O-glycosylation in differentiated cultures with benzyl-alpha-GalNAc resulted in increased adhesion of applied corneal epithelial cells and corneal fibroblasts. The antiadhesive effect of mucin O-glycans was further demonstrated by fluorescence video microscopy in dynamic flow adhesion assays. Cationized ferritin labeling of the cell surface indicated that anionic repulsion did not contribute to the antiadhesive character of the apical surface.
CONCLUSIONS: These results indicate that epithelial O-glycans contribute to the antiadhesive properties of cell surface-associated mucins in corneal epithelial cells and suggest that alterations in mucin O-glycosylation are involved in the pathology of drying mucosal diseases (e.g., dry eye).

Study: Systane (literature review)

Dr. Foulks had a review of Systane published recently. Nothing earth-shattering in the abstract, basically the easily believable notion that "It's better than several other drops out there".

Clinical evaluation of the efficacy of PEG/PG lubricant eye drops with gelling agent (HP-Guar) for the relief of the signs and symptoms of dry eye disease: A review.

Foulks GN.
Drugs Today (Barc). 2007 Dec;43(12):887-96

The objective of this review is to evaluate the efficacy of polyethylene glycol (PEG) 400/propylen glycol (PG) in-situ gellable lubricant eye drops with HP-Guar (as the gelling agent) in reducing dry eye signs and symptom. A systematic literature search utilizing MEDLINE was conducted to identify peer-reviewed articles related to dry eye disease and in-situ PEG/PG gellable lubricant eye drops. The search covered the period prior to July 2007. Articles were selected based on their direct applicability to the subject matter. A manual search was also conducted based on citations in the published literature. Additional original reports were referenced at the author's discretion if deemed applicable to the subject matter of the review. Forty-three (43) articles were identified and are reviewed here. The published literature indicated that dry eye disease is a prevalent condition in the United States, especially among women and the elderly. The biphasic mechanism of action of in-situ PEG/PG gellable lubricant eye drops, afforded by their unique structure, renders them more effective at reducing the signs and symptoms of dry eye than many commercially available over-the-counter products. (c) 2007 Prous Science. All rights reserved.

Newsblurb: Autologous serum

While autologous serum certainly can't be considered a new breakthrough, I'm encouraged to see a little popular press about it to spread the word. Also this is a heads up to folks in the midwest for another dr. with experience in using serum drops.

St. John’s doctor uses 'breakthrough' eye drops to treat severe dryness

St. John’s Clinic ophthalmologist Dr. Shachar Tauber has begun using what he calls “a breakthrough alternative” in the treatment of patients with severe dry eye.

Autologous serum drops are eye drops are made from the patient’s own blood, he said....

“We use these drops in intervals for patients who have shingles and who have had Lasik and PRK procedures,” Tauber said. “We don’t know what chemical it is exactly in blood that has the healing property; we think it’s the combination of proteins such as albumin and insulin, and the body’s stem cells. They all work in concert to promote healing in the eyes when nothing else helps.”

Tauber has treated about 50 patients who have severe dry eye with autologous serum drops. Patients often have eyes that are very swollen and inflamed most of the times and no eye drops seem to help, he said. Some are in severe pain and can’t keep their eyes open....

Study: Punctal plugs in an empty socket

I thought this was kind of interesting. People without corneas need tears too... I wonder if they get into the "cesspool effect" debate like us.

Favorable effects of lacrimal plugs in patients with an anophthalmic socket.
Vardizer Y, Lang Y, Mourits MP, Briscoe MD.
Orbit. 2007 Dec;26(4):263-6

Background: The use of punctal plugs in the treatment of dry eyes is well established. Anophthalmic patients have less tears in the anophthalmic socket in comparison to their normal side, due to an absent corneal reflex.... Many of those patients complain of dry eye symptoms, even when they are treated with tear replacement therapy. The authors wished to examine whether they could improve their dry socket complaints with punctal plugs.
Purpose: To evaluate the clinical efficacy and tolerability of punctal plug (Smart Plugs(R)) insertion in anophthalmic patients with symptoms of dry eye.
Patients and methods: Interventional case series. Fifteen anophthalmic patients with dry eye symptoms, a Schirmer test of less than 3 mm and an open lacrimal passage were examined before and after insertion of punctal plugs. The patients were asked for their subjective evaluation of the treatment and were examined to evaluate the change. Schirmer tests were compared. Bacterial cultures were taken at both visits.
Results: Schirmer results of less than 3 mm in the anophthalmic socket were obtained in 75% of patients with dry eyes symptoms; 87% of patients in whom punctal plugs were inserted reported an improvement in dry eye sensation. More than half of the patients demonstrated less discharge.... Schirmer tests improved from 1.4 mm to 1.9 mm.... Patients with a Schirmer outcome of 2 mm or more tended to have less pathogenic bacterial cultures....
Conclusion: Punctal plugs improve the symptoms and signs of dry socket. Punctal plugs seem to reduce the pathogenic bacterial growth in the anophthalmic socket.

Study: Post lasik woe referrals

Any LASIK patient out there who has felt like they got the big brush-off about their postop complaints may find this interesting study validating. I don't think it needs commentary - the facts are pretty straightforward.

Referrals to the Wills Eye Institute Cornea Service after laser in situ keratomileusis: Reasons for patient dissatisfaction.
Levinson BA, Rapuano CJ, Cohen EJ, Hammersmith KM, Ayres BD, Laibson PR.
J Cataract Refract Surg. 2008 Jan;34(1):32-9

PURPOSE: To review the symptoms, findings, and management options in patients referred to the Cornea Service who were unsatisfied with results after laser in situ keratomileusis (LASIK).
SETTING: Cornea Service, Wills Eye Institute, Philadelphia, Pennsylvania, USA.
METHODS: A retrospective chart review was conducted of all patients seen for consultation between January 1, 2004, and December 31, 2006, who had LASIK performed elsewhere. The parameters extracted were demographic data, history, symptoms, postoperative best corrected and uncorrected visual acuities, surgical complications, examination findings, and treatment recommendations. The data were also compared with previously unpublished data collected at Wills Eye from 1998 to 2003.
RESULTS: One hundred fifty-seven eyes of 109 patients seen in consultation after LASIK were identified. Twenty-eight percent were referred by the LASIK surgeon and 54%, by another eye doctor; 17% were self-referred. The most common chief complaints were poor distance vision (63%), dry eyes (19%), redness/pain (7%), and glare and halos (5%). Forty-four eyes (28%) had surgical complications or enhancements. The most common diagnoses were dry eye or blepharitis (27.8%), irregular astigmatism (12.1%), and epithelial ingrowth (9.1%). Eleven percent were referred in the first month after LASIK; 23% and 10% were referred between 1 and 6 months and 7 and 12 months, respectively. Medical management (eg, artificial tears, steroids, other dry-eye treatment) was offered in 39% of cases, surgical intervention in 27%, and observation only in 7%. Nonsurgical therapy was offered in 73% of cases.
CONCLUSIONS: Most patients who came for consultation were referred by a doctor other than their LASIK surgeon. Poor distance vision, dry eye, redness/pain, and glare and halos were the most common chief complaints and dry eye or blepharitis, irregular astigmatism, and epithelial ingrowth, the most common diagnoses.

Study: What's different about MGD

This study is no less welcome for having results that are kind of self-evident, i.e. if you've got MGD, your oil composition will be different. If it helps lead to a better diagnostic methodology that picks up on MGD, so much the better, though I still say, docs really oughtta get more hands-on teaching about the physical signs of lid margin disease in school.

Differences in meibomian fatty acid composition in patients with meibomian gland dysfunction and aqueous-deficient dry eye.
Joffre C, Souchier M, Grégoire S, Viau S, Bretillon L, Acar N, Bron AM, Creuzot-Garcher C.
Br J Ophthalmol. 2008 Jan;92(1):116-9

AIMS: To evaluate the differences in meibomian fatty acid composition in healthy subjects and in patients suffering from meibomian gland dysfunction or aqueous-deficient dry eye.
METHODS: We collected meibomian oil using a sterile Schirmer paper in healthy individuals (n = 20), dry eye patients (aqueous-deficient) (n = 32) and meibomian gland dysfunction (MGD) patients (n = 25) after gentle massage of the lid margin. Meibomian fatty acids were directly transmethylated and analysed using gas chromatography (GC) and GC mass spectrometry.
RESULTS: Meibomian fatty acids were similar in healthy individuals and in dry eye patients but were different in MGD patients, who showed significantly higher levels of branched-chain fatty acids (29.8% vs 20.2%) (p<0.0001) and lower levels of saturated fatty acids (9.3 vs 24.6%) (p<0.0001), in particular lower levels of palmitic (C16) and stearic (C18) acids.
CONCLUSION: The increase in branched-chain fatty acids may reflect greater quantities of wax and cholesterol esters and triglycerides in meibomian gland excreta. Since wax and cholesterol esters are the main lipids of meibum, these differences may have physical consequences for tear-film lipid-layer fluidity and stability. Meibomian fatty acid composition and particularly the increase in branched chains could be a marker for meibomian gland dysfunction.