Off the Cuff: Look and Ye Shall See

Just back from a scientific symposium addressing ocular and contact lens surface interaction, where a large part of the discussion focused on corneal staining. With the current mix of new contact lens materials and older preservatives in some solutions, staining has become a huge problem, one that has gone largely unnoticed by many front-line clinicians.

Staining remains so well hidden for two primary reasons. The first is that many do not use fluorescein when examining contact lens patients. The second is even more insidious. Clinical experience and scientific research show no correlation between staining and patient discomfort. Nevertheless, solution-related staining does damage to the ocular surface, which triggers inflammation--even though both patient and practitioner frequently remain unaware.

New research may help explain why patients remain asymptomatic. Soon-to-be published data suggests that biguanide-based care products diminish corneal sensitivity. Our patients remain blissfully unaware of the discomfort caused by surface compromise, while something is driving them away in droves from wearing contact lenses.

We may not have all the answers yet, but we need to recognize that staining is a significant risk factor in lens wear--one that can be easily identified and then controlled by prescribing appropriate lens and lens care product combinations.

Arthur B. Epstein, OD, FAAO Chief Medical Editor artepstein@optometricphysician.com

Case in Point: Endogenous Endophthalmitis

A 52-year-old man presented to the eye clinic complaining of a red, painful left eye with blurred vision. He reported that the condition had begun three days prior and that it was getting progressively worse.

The patient’s medical diagnoses included Type II diabetes, chronic hepatitis C, alcohol dependence and pseudophakia OU with uncomplicated cataract extraction four years earlier. He denied any history of trauma, and he had no systemic complaints.

Visual acuity measured 20/25 OD and finger counting OS. Biomicroscopy revealed a 1.4 mm hypopyon OS with 3+ cells and flare in the anterior chamber (see photo). Posterior chamber IOLs were well positioned OU. Ultrasonography demonstrated significant vitreous debris.

An intravitreal tap was performed, and the cultures grew Streptococcus viridans. Endogenous endopthalmitis was diagnosed. Intravenous, intravitreal and topical antibiotics, in addition to topical steroids, were instituted. The hypopyon resolved within four days, and the vitritis slowly improved over one month, with acuity returning to 20/25 OS. A systemic work-up, including blood cultures, isolated methicillin-resistant Staphylococcus aureus bacteremia, which cleared in five days on intravenous therapy. Urinalysis and transesophageal echocardiogram were negative. The patient remained afebrile, having only ocular symptoms throughout the episode.

Endophthalmitis can be categorized as postoperative (acute and chronic), traumatic, bleb-related or endogenous. The organisms causing endophthalmitis usually reach the eye from the outside environment. Less frequently, they gain access hematogenously (i.e., through the blood), resulting in endogenous endophthalmitis.

A retrospective study of 22 endogenous bacterial endophthalmitis cases found that 70 percent of the patients had diabetes mellitus combined with urinary tract infection; diagnoses were made 3.5 days after the beginning of symptoms (Laube T, Akgul H, Brockmann C, et al. [Endogenous bacterial endophthalmitis: a retrospective study on 22 consecutive cases.] Klin Monatsbl Augenheilkd 2004; 221(2):101-8. German). Although this patient achieved excellent visual outcome, this is an atypical case. Most cases of endogenous endophthalmitis result in severe vision loss. Early diagnosis and therapy are crucial for a positive outcome in this ocular emergency.

-- Case study courtesy of Dianne Kowing, MS, OD, FAAO, Chief of Optometry, Daytona Beach VA Outpatient Clinic, Daytona Beach, FL.

Non-Mydriatic Digital Photography Inadequate for Diabetic Screening

One hundred consecutive diabetic patients (200 eyes) underwent 45-degree, non-mydriatic digital fundus photography and ocular examinations between June and November, 2002. One image was obtained focusing the mid-fundus between the optic disc and the macula. The fundus images were printed and graded by endocrinologists and a retinal specialist separately. The patients also underwent complete standard examinations, including dilation and slitlamp biomicroscopy as the reference method for determining diabetic retinopathy.

The sensitivity and specificity of the retinal specialist’s diabetic retinopathy grades were 53.8 percent and 89.0 percent, respectively. The sensitivity and specificity of the endocrinologists’ grades were 45 percent and 75.3 percent, respectively. The false negative rates were 22 percent and 21.5 percent for endocrinologists and the retinal specialist, respectively. The results suggest that screening for diabetic retinopathy using one-field, non-mydriatic, 45-degree digital photography is inadequate.

SOURCE: Kuo HK, Hsieh HH, Liu RT. Screening for diabetic retinopathy by one-field, non-mydriatic, 45 degrees digital photography is inadequate. Ophthalmologica 2005;219(5):292-6.

Effect of Hinge Position on Dry Eye After LASIK

In this prospective clinical trial, 212 consecutive eyes of 106 myopic patients underwent LASIK. In each patient, one eye was randomly assigned to the superior hinge and the other eye to the nasal hinge procedure. The patients were examined pre-operatively and one week, one month, three months and six months after surgery for visual acuity, fluorescein tear film breakup time and Schirmer's baseline tear secretion test. A subjective evaluation of dry eye symptoms was accomplished by the Ocular Surface Disease Index questionnaire at the one-month, three-month and six-month postoperative visits.

Tear film breakup time was not significantly different with the nasal or superior hinge flap technique at the preoperative, one-week, one-month, three-month and six-month visits. No significant difference between the two groups was found for the Schirmer's test at pre- and postoperative visits. Subjective evaluation of symptoms also showed no significant difference at the one-month, three-month and six-month postoperative visits.

The nasal and superior hinge flap methods do not affect signs and symptoms of dry eye after LASIK.

SOURCE: Ghoreishi M, Aidenloo NS, Peyman A, et al. Does hinge position affect dry eye after laser in situ keratomileusis? Ophthalmologica 2005;219(5):276-80.

Visual Acuity and Central Retinal Thickness in Retinitis Pigmentosa

Visual acuities were measured with Early Treatment Diabetic Retinopathy Study (ETDRS) charts, and optical coherence tomography (OCT3) was used to calculate retinal thicknesses and grade third high-reflectance bands in 162 patients with retinitis pigmentosa who had Snellen visual acuities of 20/20 to 20/200, minimal to no cataracts and no visible macular cysts. Sixty-five patients were retested within two months to estimate the intervisit variability of retinal thickness measurements.

ETDRS acuity was best related to retinal thickness measured at fixation and as the average value over the central 1 mm. Acuity was maximal for intermediate retinal thickness and appeared to decline for lesser and greater retinal thicknesses. The decline in acuity for decreasing retinal thickness was steeper in eyes with an absent third high-reflectance band than for eyes with a partially distinct band. No decline was noted in eyes with an intact band.

Both retinal thinning (due to cell loss) and retinal thickening (due to presumed edema) appear to be associated with lower visual acuity in patients with retinitis pigmentosa. The definition of the OCT third high-reflectance band may help to predict which patients are more likely to lose visual acuity as retinal thickness declines.

SOURCE: Sandberg MA, Brockhurst RJ, Gaudio AR, Berson EL. The association between visual acuity and central retinal thickness in retinitis pigmentosa. Invest Ophthalmol Vis Sci 2005;46(9):3349-54.

Factors Influencing the Outcome of Amblyopia Treatment

This intervention study consisting of three non-overlapping phases: "Baseline," "refractive adaptation" (18 weeks of full-time spectacle wear) and "occlusion" (six hours of patching per day, objectively monitored) assessed factors such as type of amblyopia, age, initial severity of amblyopia and fixation on visual outcome. Visual outcome was expressed in three ways: logMAR change, residual amblyopia and proportion of the deficit corrected. The study included 85 amblyopics associated with strabismus (32 patients) or anisometropia (20 patients), or associated with both anisometropia and strabismus (33 patients).

Cumulative occlusion dose exceeding 50 hours, and dose rates one hour per day or longer resulted in lower residual amblyopia and a greater proportion of the deficit corrected. High residual amblyopia were present in patients with eccentric fixation, severe initial amblyopia and no binocular vision.

Factors influencing outcome of amblyopia treatment are occlusion dose (the rate of delivery and cumulative dose worn), initial severity of the amblyopia, binocular vision status, fixation of the amblyopic eye and the age of the subject at the start of treatment.

SOURCE: Stewart CE, Fielder AR, Stephens DA, Moseley MJ. Treatment of unilateral amblyopia: factors influencing visual outcome. Invest Ophthalmol Vis Sci 2005;46(9):3152-60.

NEWS & NOTES

	CONTACT LENS PROFESSIONAL ADVERTISING ACTIVITY INCREASES EIGHT PERCENT IN FIRST HALF OF 2005. Manufacturers of soft and rigid contact lens and lens care products increased their investments in professional advertising by 8 percent during the first half of 2005 to $2.0 million, according to the Eyecare Competition Monitor, a service of Gerber Communications. The Eyecare Competition Monitor measures spending for advertising pages, advertorials, continuing education sponsorships and other paid promotional messages in 10 leading journals that reach contact lens fitters. The service also tracks news coverage received by each company in professional print and electronic media. Spending data show that soft lens companies increased spending by three percent during the first half, while RGP companies raised spending by eight percent and lens care companies by 29 percent. The most heavily advertised lens category during the first six months of this year was silicone hydrogel lenses, accounting for 53 percent of total soft contact lens spending. Spending by ophthalmic pharmaceutical companies increased 23 percent during the first half and totaled $2.3 million, greater than combined lens and lens care spending. For more information on the Eyecare Competition Monitor, contact Access Media Group, LLC, at (610) 492-1004 or (610) 492-1033.
	PHARMACEUTICAL COMPANY SIGNS AGREEMENT TO LICENSE NANOTECHNOLOGY TO DEVELOP ALLERGY PRODUCTS. Illinois-based BioSante Pharmaceuticals, Inc. announced that it has signed a Material Transfer and Option Agreement with an undisclosed European pharmaceutical company for an option to obtain an exclusive, worldwide license to use BioSante's calcium phosphate nanotechnology (CaP) to develop a series of allergy products. The partner company will fund its development of potential products for the treatment of conditions including rhinitis, asthma, conjunctivitis and dermatitis. Under the terms of the option agreement, BioSante will receive a $250,000 upfront option payment. If the option is exercised and the parties enter into an exclusive license agreement, BioSante will receive a one-time license fee, annual maintenance payments, milestone payments upon the achievement of regulatory milestones and royalties on commercial sales of any allergy product that is developed using CaP. For more information, go to www.biosantepharma.com.
	TRANSPLANT REJECTION DRUG LOOKS PROMISING FOR TREATING INFLAMMATORY EYE DISEASE. Mycophenolate mofetil, an immunosuppresive drug used to prevent rejection of transplanted hearts, kidneys and livers, may also be effective in controlling inflammatory eye diseases, according to researchers at Johns Hopkins. Investigators said that the drug seemed to be effective even in patients who had failed treatment from other immunosuppressants. Eighty-four patients received the drug, of whom 61 percent had uveitis, 17 percent had scleritis, 11 percent had mucous membrane pemphigoid and 11 percent had inflammation behind the eye or in other areas. Patients took two pills each morning and two each evening, for a total dose of 2 grams daily. Thirty-six patients (43 percent) already had been treated with at least one other immunosuppressive drug. The results of the study, published in the August 2005 issue of Ophthalmology, showed that 81 patients (97 percent) had control of their ocular inflammation after one month of treatment. Eighty-two percent of patients had control of their inflammation and were able to taper their dose of the steroid prednisone to 10 or fewer mg daily. Seven patients discontinued the drug because of adverse effects such as stomach upset or mild diarrhea. In most cases, said the chief investigator, lowering the dose of medication reduced side effects. The drug dosage can then be increased without the side effects returning.

	It’s only been up and running a few short weeks. Yet, it’s already clear that the Check Yearly. See Clearly.(SM) marketing campaign is opening consumers’ eyes to the benefits of regular eye exams. Call the Vision Council of America at 800-424-8422 today or visit checkyearly.com for your free promotional materials.