蕭裕泉醫師眼科筆記

Foveal contrast sensitivity affected by glaucoma by Matt Young EyeWorld Contributing Editor Could contrast sensitivity testing help detect glaucoma earlier? A scene as it might be viewed by a person with glaucoma. A new study found that central vision is significantly decreased by the disease Source: National Eye Institute, In contrast to conventional wisdom, new research finds that sharp central vision is significantly decreased by glaucoma. The research, published in January in Archives of Ophthalmology, found significantly lower foveal contrast sensitivity in both photopic and mesopic conditions in eyes with glaucoma. “The maintenance of good visual acuity until late in the disease and the absence of characteristic central visual field defects lead to the belief that the fovea remains unaffected in the early stages of the disease,” reported co-lead study author Hani Levkovitch-Verbin, M.D., Goldschleger Eye Institute, Sheba Medical Center, Tel-Hashomer, Israel. “Ho...

Phacoemulsification sleeve frequently overlooked prior to use by Matt Young EyeWorld Contributing Editor Last summer, Dr. Johansson's office noticed a problem with the phacoemulsification equipment when preparing for a coaxial micro-incision surgery. The operation staff observed that the protection chamber and one silicone sleeve were firmly attached to each other inside the package. The very thin silicone sleeve could have been easily damaged during handling and separation of the two items. In this case, the equipment was exchanged completely, and the observation was reported to the manufacturer. The surgery was uneventful Source: Bjorn Johansson, M.D. Although clinical staff must examine surgical instrumentation before use, a recent report recommends taking time to explore one element that tends to be overlooked: the phacoemulsification sleeve. “In addition to examining the irrigation and aspiration of the phacoemulsification probe, we recommend spa...

Blue light-filtering lens reduces accident risk in simulator by Maxine Lipner Senior EyeWorld Contributing Editor Testing in a driving simulator showed that patients with blue light-filtering lenses had an edge in glare conditions Source: Robert D. Gray, Ph.D. AcrySof Natural lens may help ameliorate glare problems while driving Patients who receive the AcrySof Natural SN60AT (Alcon, Fort Worth, Texas) blue light-filtering lens are not only less susceptible to glare, but also experience fewer collisions with oncoming cars than those with traditional lenses, according to Robert D. Gray, Ph.D., senior lecturer, School of Sport and Exercise Science, University of Birmingham, England. In the January issue of the Journal of Cataract and Refractive Surgery, investigators led by Dr. Gray compared the effects of glare on those who received the blue light-filtering lens to those with a comparable acrylic IOL with no blue light filter. This study was an outgrowth of an earlie...

Femtosecond phenomenon: Burgeoning alternative applications by Maxine Lipner Senior EyeWorld Contributing Editor Considering new possibilities for femtosecond technology from lenticule extraction to etching flaps with the femtosecond laser and more, this technology is making inroads in many areas of ophthalmology, according to Ginny L. Kullman, M.D., assistant professor, Ochsner Medical Center, New Orleans. In the September-November 2010 issue of Seminars in Ophthalmology, Dr. Kullman, together with Roberto Pineda, M.D., assistant professor of ophthalmology, Harvard Medical School, Boston, and director of refractive surgery, Massachusetts Eye and Ear Infirmary, Boston, reviewed the latest advances in this area. “I was doing my fellowship at Massachusetts Eye and Ear and we had a research core review project —the topic was technological advances in the field of ophthalmology,” Dr. Kullman said. “I wanted to target it more to cornea as I was doing a cornea fellowship.” Dr. Kul...

[June 2011 EyeWorld] Cataract and glaucoma don't go together like a horse and carriage by Matt Young EyeWorld Contributing Editor There are problems treating both diseases in the same patient, but modern solutions exist      A new report refers to cataract as the "silent enemy" in relation to glaucoma and trabeculectomy surgery, and it's no wonder why. In a nutshell, cataract formation is likely after trabeculectomy surgery. Subsequent cataract surgery leads to frequent bleb failure. Cataract surgery in patients requiring filtration surgery remains an issue of contention, according to the report, published online in January in the British Journal of Ophthalmology. "Cataract should not remain the silent enemy of successful trabeculectomy surgery," lead author Rashmi G. Mathew, M.R.C.Ophth., Moorfields Eye Hospital, London, said in the report. "Reviewing the literature does provide clarity on some issues surrounding this topic."    It's...

[June 2011 EyeWorld] Presbyopia-correcting IOL pearls by Faith A. Hayden EyeWorld Staff Writer  An implanted ReSTOR IOL (Alcon) Source: Richard Tipperman, M.D.     No matter which presbyopia-correcting IOL you favor, be it the ReSTOR (Alcon, Fort Worth, Texas), Tecnis (Abbott Medical Optics, AMO, Santa Ana, Calif.), or Crystalens (Bausch & Lomb, Rochester, N.Y.), experts agree that achieving the best possible outcomes begins with one critical component: the pre-op exam. EyeWorld spoke with Richard Tipperman, M.D., Wills Eye Hospital, Philadelphia; Y. Ralph Chu, M.D., adjunct associate professor of ophthalmology, University of Minnesota, Minneapolis, and clinical professor of ophthalmology, University of Utah, Salt Lake City; and William B. Trattler, M.D., cornea specialist, Center for Excellence in Eye Care, Miami, for tips on attaining spectacular outcomes with each and every patient. The feedback was largely universal. Proper patient selection and an extensive ...

     Cataract Surgery may Benefit Alzheimer’s patients A group of French researchers presented findings that patients with mild Alzheimer's disease whose vision improved after cataract surgery also showed improvement in cognitive ability, mood, sleep patterns, and other behaviors. Presenting last week at the American Academy of Ophthalmology meeting, Brigitte Girard, M.D. , said hers is the first study to specifically assess whether cataract surgery could benefit Alzheimer's patients, although earlier research had shown that poor vision is related to impaired mood and thinking skills in older people and that cataract surgery could improve their quality of life. She enrolled 38 patients (average age: 85 years) who all exhibited mild dementia due to Alzheimer's disease. All participants had a debilitating catara...

Retinoic acid may be key to dry, wet AMD treatments by Michelle Dalton EyeWorld Contributing Editor ------------------------------------------------------------ Patients receiving the 300 mg dose of fenretinide showed significant reduction of retinol binding protein and reduced lesion growth from baseline when compared to placebo Source: ReVision Therapeutics A synthetic retinoid derivative has been able to slow lesion growth and preserve visual acuity in patients with geographic atrophy (GA). Further, when the patients were able to achieve sustained reductions in retinol binding protein (RBP) levels of 60-75% (indicating a positive response to fenretinide), these same patients had a lesion growth rate of about half what those receiving placebo experienced when the RBP reduction threshold was met. "Fenretinide may improve clinical outcomes for patients with both dry and wet forms of age-related macular degeneration," said Jason Slakter, M.D., clinical professor of ophth...

Steroid reliance too common in treating uveitis by Jena Passut EyeWorld Staff Writer -------------------------------------------------------------------------------- Although steroids are useful in treating uveitis (pictured here), long-term use results in side effects, such as cataracts Source: Manolette Roque, M.D. More training with uveitis experts is needed; disease is curable with immunosuppressive therapy Despite major inroads in the treatment of many ocular diseases, uveitis rates have remained nearly the same for the past 35 years. The disease has an estimated prevalence of 38 in 100,000. Of that, 10% of patients will become blind. "The reason that there has been no significant progress in driving down the prevalence in developed countries around the world is because of the exclusive reliance on steroid therapy by the bulk of ophthalmologists who care for patients with uveitis," said C. Stephen Foster, M.D., clinical professor of ophthalmology, Harva...

Deciphering dry eye therapies by Faith A. Hayden EyeWorld Staff Writer -------------------------------------------------------------------------------- Dry eye syndrome (DES) is one of the most common reasons a patient presents to an ophthalmologist's office. It affects 10-15% of U.S. adults, or about 80 million people. DES usually affects post-menopausal women, adults over the age of 65, and younger individuals who wear contacts for extended periods of time. Other diseases such as diabetes, rheumatoid arthritis, lupus, and Sjogren's syndrome can also bring on DES. There is no perfect or agreed-upon solution for the disease, and every doctor seems to have his or her own preferred management method. Treatment for this condition varies wildly, often depending on the cause of the disease, severity of the symptoms, and lifestyle of the patient. When deciding which therapy to prescribe to a patient suffering from the itchiness, redness, and pain associated with this cond...

Treating dry eye by Vanessa Caceres EyeWorld Contributing Editor Telangiectasia of the lid margin; inspissated gland orifices and a large glob of meibum plugging the duct in a patient with significant blepharitis A patient with significant dry eye from blepharitis. Inferior corneal staining with fluorescein and rapid tear film break-up, particularly in the peripheral cornea in a vertical streak fashion, are indicative of evaporative dry eye syndrome from blepharitis Source: Esen K. Akpek, M.D. Multifaceted approach often needed Even though dry eye disease has become more of an ophthalmic superstar in recent years—garnering attention both from ophthalmologists and the general public—the condition is still underdiagnosed and undertreated, said John D. Sheppard, M.D., professor of ophthalmology, microbiology, and immunology, Eastern Virginia Medical School, Norfolk. Add to this the consideration that FDA drug approvals have weakened, and practitioners have a smaller nu...

Diagnosing dry eye by Michelle Dalton EyeWorld Contributing Editor Clinical signs and patient-reported symptoms may not correlate; patient symptoms must take precedence An eye with a poor tear film surface Source: Gary Foulks, M.D. Lissamine green staining helps clarify the severity of the ocular surface Poor tear break-up time is also indicative of increased dry eye severity Source: Gary Foulks, M.D. One of the most common reasons people visit eyecare specialists is due to complaints of dry eye, yet specialists and those in general practice believe the numbers are wildly underestimated. "In my practice, 40-50% will have some form or complaint of ocular surface dysfunction," said Christopher E. Starr, M.D., assistant professor of ophthalmology, and director, cornea, cataract, and refractive surgery fellowship and service, Weill Cornell Medical College, New York. According to Caroline Blackie, O.D., Ph.D., clinical research scientist, Korb Associates,...