EyeNet Magazine


 
Journal Highlights
New Findings from Ophthalmology, AJO and Archives
 
 
Orbital Irradiation as a Treatment for Graves’ Ophthalmopathy

Glaucomatous and Ischemic Optic Nerve Damage After Acute Primary Angle-Closure Attack

Emotional Impact Is Minimal for Preschool Children Who Are Being Treated for Amblyopia

Dolasetron Not Equivalent Substitute to Droperidol in Controlling Postop Nausea

Factors That Contribute to the Failure of Glaucoma Detection by Eye Health Professionals

Trypan Blue–Assisted Vitrectomy for Macular Pucker

Oral Cevimeline Effective in Treatment of Dry Eye in Patients With Sjögren’s Syndrome

Super Blue-Green Algae as an Adjunct to Botox Injections

In Rabbits, Topical Prophylaxis With Moxifloxacin Can Prevent Bacterial Endophthalmitis

Cholesterol-Lowering Medication Use and Glaucoma

PDT for Subfoveal Choroidal Neovascularization in AMD

Prospective Study of Intake of Fruits, Vegetables, Vitamins and Carotenoids and the Risk of ARM

Bacterial Conjunctival Flora in Diabetic Patients

An Adjunct to Coronal Computed Tomography in Evaluating Orbital Floor Fractures


Previews

Orbital Irradiation as a Treatment for Graves’ Ophthalmopathy
August’s Ophthalmology

A study by Wakelkamp et al. found that orbital irradiation for Graves’ ophthalmopathy is a safe treatment approach in the long term—with the possible exception in individuals with diabetes.

The investigators conducted an 11-year follow-up study of 245 patients with Graves’ ophthalmopathy who were treated with retrobulbar irradiation (20 Gy in two weeks) and/or oral glucocorticoids between 1982 and 1993.

Of the 245 patients, 37 had died during the follow-up period, yet none from an intracranial tumor. Of the individuals who participated in the follow-up study (157 of 208 living patients), possible retinopathy was present in 15 percent of them—22 of the irradiated and one of the nonirradiated patients. In five patients (all had been irradiated), definite retinopathy was present. Diabetes was associated with both possible and definite retinopathy.

The researchers conclude that while orbital irradiation for Graves’ ophthalmopathy appears to be safe in the long term, diabetes mellitus is a possible contraindication.

Glaucomatous and Ischemic Optic Nerve Damage After Acute Primary Angle-Closure Attack
August’s Ophthalmology

An acute attack of primary angle-closure is not something to be taken lightly.

In a study of 90 Asians (predominantly Chinese) who experienced such an attack, Aung et al. found that within a mean interval of six years, one-fifth were blind in the attack eye, with glaucoma responsible for the blindness in 50 percent of them.

Almost half had glaucomatous optic neuropathy, and a third of those with glaucoma had severely cupped optic discs. Vision also was reduced in a large number of these individuals, mostly from unoperated cataract. According to the investigators, this group of patients—seen at Singapore hospitals—experienced high rates of glaucomatous and ischemic optic nerve damage despite access to “relatively high-quality” ophthalmic treatment.

Predicting that outcomes in less-developed settings will be worse, they emphasize the need for advances in screening and prophylactic treatment.

Emotional Impact Is Minimal for Preschool Children Who Are Being Treated for Amblyopia
August’s Ophthalmology

Hisos et al. conducted the largest survey to date quantifying the emotional impact of active amblyopia treatment for unilateral visual impairment in preschoolers.

They found that while treatment can be distressing and quite bothersome, they detected no repercussions on a child’s global well-being or behavior either during or after treatment. This study was conducted in the context of a prospective randomized controlled trial already under way. Participants, who were referred from preschool vision screening, had been assigned to receive either glasses with or without patches, glasses alone or treatment deferred for one year.

In self-completion questionnaires, most parents reported difficulty with patching their child regardless of age, with fewer reporting difficulties with glasses alone. While children were significantly more upset by patching than by glasses only, most parents thought their children were happy, cooperative and good-tempered, and behavioral scores did not differ between treatment groups.

The authors conclude that despite a degree of distress, amblyopia treatment does not lead to subsequent behavior problems.

Dolasetron Not Equivalent Substitute to Droperidol in Controlling Postop Nausea
August’s Ophthalmology

Vitreoretinal surgery is associated with a considerable incidence of postoperative nausea and vomiting, which can induce intraocular bleeding.

Droperidol (Inapsine) is an antiemetic that can be administered prophylactically during anesthesia to reduce the incidence of postop nausea and vomiting. However, the FDA has required a “black box” warning on the droperidol package insert regarding the risk of serious proarrhythmogenic effects.

In trying to find a suitable alternative, Eberhart et al. conducted a placebo-controlled, double-blinded trial comparing droperidol with dolasetron —or the combination of both drugs— to saline.

The reduction of the incidence and severity of postop nausea and vomiting was statistically significant in the droperidol group and the combination group relative to the placebo. However, dolasetron alone failed to reduce the incidence of postop nausea and vomiting. The combination of the two drugs revealed an additive antiemetic efficacy.

The authors conclude that dolasetron is not an equivalent substitute for droperidol in preventing postop nausea and vomiting but can be used for supplementation in high-risk patients.

Factors That Contribute to the Failure of Glaucoma Detection by Eye Health Professionals
August’s Ophthalmology

Wong et al. determined factors that may contribute to the failure by eye health professionals to detect glaucoma in their patients.

In this study, the investigators examined clinical features of undiagnosed primary open-angle glaucoma in people who visited an eye care provider within the previous 12 months.

In the sample of 4,744 participants, 35 undiagnosed and 43 diagnosed participants had visited an optometrist or ophthalmologist or both in the previous 12 months. The only statistically significant variables between the diagnosed and undiagnosed glaucoma groups were the presence of visual field defects and the type of eye care provider seen. In addition to raised vertical cup-to-disc ratio and IOP, Humphrey visual field abnormalities were the important clinical factors when comparing participants.

They conclude that raised IOP should not be relied on as the only sign of possible glaucoma, and alternatives to Humphrey visual field testing (which can be expensive and time-consuming) should be explored to improve glaucoma detection.

_______________________________
Ophthalmology previews are written by Lori Baker Schena and edited by John Kerrison, MD.

Reviews

Trypan Blue–Assisted Vitrectomy for Macular Pucker
American Journal of Ophthalmology
2004;138:1-5

Haritoglou et al. have expanded their studies on safe products that assist in visualizing structures for macular surgery.

They evaluated the functional outcome after the intraoperative application of 0.06 percent trypan blue during vitrectomy for macular pucker in a prospective randomized comparative study of 43 eyes.

Patients were randomized into two groups: Group 1 with trypan blue and Group 2 without trypan blue staining. Functional outcome (BCVA, Goldman perimetry) was evaluated one day before surgery and at six-week, three-month, six-month and 12-or-more month intervals postoperatively. Only patients with an idiopathic macular pucker were included, and all patients received a standard three-port pars plana vitrectomy with peeling of an epiretinal membrane and the internal limiting membrane.

Median BCVA was 20/63 in both groups (range 20/200 to 20/40; P > 0.5) before surgery. Mean follow-up time was 5.8 months in Group 1 and 5.3 months in Group 2. After surgery, median visual acuity had increased to 20/40 in both groups (range 20/500 to 20/20 in Group 1 and 20/100 to 20/20 in Group 2; P < 0.001 for both groups). The difference between both groups was not statistically significant (P > 0.5). An improvement of visual acuity (gain of two or more lines) was seen in 16 patients of both groups. No postoperative visual field defects were noted.

Trypan blue–assisted vitrectomy for macular pucker led to good functional results with no dye-related adverse effects after short follow-up. Trypan blue might be especially applicable in cases where the borders of the epiretinal membrane are difficult to define. Hypothetical advantages, such as less recurrence of epiretinal membranes after trypan blue staining, will have to be evaluated during further follow-up of patients.

Oral Cevimeline Effective in Treatment of Dry Eye in Patients With Sjögren’s Syndrome
American Journal of Ophthalmology
2004;138:6-17

Sjögren’s syndrome is a systemic autoimmune disease characterized by salivary and lacrimal glandular destruction leading to symptoms of dry mouth and dry eye. Patients with this syndrome have autoantibodies that bind to muscarinic acetylcholine receptors in the exocrine glands. A muscarinic acetylcholine receptor agonist, cevimeline, has been approved for treatment of symptoms of dry mouth in patients with Sjögren’s syndrome. Ono et al. evaluated the efficacy of cevimeline in improving symptoms of dry eye in a retrospective, randomized, double-blind, multicenter clinical study.

The researchers randomly assigned 60 patients to three groups—placebo; cevimeline, 20 milligrams three times a day; or cevimeline, 30 mg three times a day—and received treatment for four weeks. Patients were evaluated before treatment, at week two, at the end of treatment and at the end of a two- to four-week follow-up period.

Compared with the placebo, statistically significant differences were seen with cevimeline, 20 mg three times a day, in subjective symptoms, tear dynamics, condition of the corneoconjunctival epithelium and global improvement rating. There were no adverse effects of the drug.

These results suggest that cevimeline, 20 mg three times a day, is safe and effective in improving symptoms of dry eye in patients with Sjögren’s syndrome.

Super Blue-Green Algae as an Adjunct to Botox Injections
American Journal of Ophthalmology
2004;138:18-32

Vitale et al. evaluated the effectiveness of super blue-green algae supplements on the severity of essential blepharospasm treated with botulinum toxin A (Botox) injections in a double-masked, placebo-controlled, two-period crossover randomized trial.

Patients with essential blepharospasm or Meige syndrome undergoing routine treatment with Botox injections were randomized to either placebo or super blue-green algae capsules. After six months of treatment, patients underwent a six-month washout period with no treatment, then were administered the alternate treatment for an additional six months, thus serving as their own controls. Video documentation of blink rate and involuntary facial movements, time between Botox injections, and patients’ subjective assessments of the impact of blepharospasm on functioning were obtained at the beginning and end of the first and second (crossover) treatment periods.

A total of 24 patients completed both treatment periods. Mean within-patient difference in blink rate and mean within-patient difference in time between injections between super blue-green algae and placebo periods was not statistically different from zero. The lack of statistical significance may have been due to small sample size. There were no significant differences in severity of involuntary movement between super blue-green algae and placebo treatment periods. However, patients were more likely to report limitation in function during the period they took super blue-green algae than during the period in which they took placebo (odds ratio = 0.2; p = 0.03).

The authors found no evidence of a beneficial effect of super blue-green algae as an adjunct to Botox injections; however, a few patients, all of whom were younger than 60 years of age, did appear to benefit from the capsules. Thus, in selected patients with blepharospasm, super blue-green algae may be useful in reducing the severity of spasms and increasing the duration between injections of Botox.

In Rabbits, Topical Prophylaxis With Moxifloxacin Can Prevent Bacterial Endophthalmitis
American Journal of Ophthalmology
2004;138:33-37

Kowalski et al. evaluated the prophylaxis potential of the topical antibiotic moxifloxacin 0.5 percent to prevent endophthalmitis following bacterial anterior chamber challenge in a rabbit model.

In this in vivo lab investigation, three regimens of topical 0.5 percent moxifloxacin were tested for prophylaxis to prevent endophthalmitis in a rabbit model. In Group 1 (full prophylaxis), moxifloxacin drops were administered every 15 minutes for one hour (five drops); anterior chamber challenge was performed with 5 x 104 colony forming units of Staphylococcus aureus, and one drop immediately and four more drops of moxifloxacin applied over the next 24 hours. Group 2 (preprophylaxis) received the same regimen minus the postchallenge prophylaxis. Group 3 (postprophylaxis) received no prechallenge prophylaxis, but did receive the S. aureus challenge, and postchallenge prophylaxis. A saline control was tested concurrently in all three experiments.

At 24 hours postinjection, the eyes were evaluated by slit lamp in a masked fashion for clinical signs of endophthalmitis, and the anterior and posterior chambers were cultured for bacteria.

The median clinical scores for the moxifloxacin group were significantly lower than the saline group for all three treatment regimens. The median clinical score for the full prophylaxis regimen was significantly lower than the pre- and postprophylaxis regimens alone. The anterior and posterior chambers were negative for S. aureus in all three moxifloxacin treatment regimens.

The authors conclude that in a rabbit model, a “proof of principle” was demonstrated that topical antibiotic therapy pre- and postintraocular bacterial challenge could prevent bacterial endophthalmitis.

Cholesterol-Lowering Medication Use and Glaucoma
Archives of Ophthalmology
2004;122:822–826

The presence of open-angle glaucoma among patients receiving statins and other cholesterol-lowering medications at the Birmingham, Ala., Veterans Affairs Medical Center was compared with age-matched controls not using statins.

McGwin et al. found that longer duration of use of statins was associated with a lower risk of open-angle glaucoma (p for trend = 0.04), primarily among patients with 24 or more months of use (odds ratio = 0.60; confidence interval = 0.39–0.92). A similar protective association was also found among those who used cholesterol-lowering agents other than statins (odds ratio = 0.59; confidence interval = 0.37–0.97).

In summary, initial examination of an administrative database suggests that chronic use of oral statins or other cholesterol-lowering drugs may be associated with a reduced risk of open-angle glaucoma.

PDT for Subfoveal Choroidal Neovascularization in AMD
Archives of Ophthalmology
2004;122:853–856

Sharma et al. compared patients with wet AMD who received verteporfin (Visudyne) therapy (n = 45) with a natural history group in order to evaluate the “real-world” effectiveness of this treatment.

Both groups were followed for the development of significant visual loss, visual stability or visual improvement. Through the use of multivariate logistic regression, patients who received verteporfin treatment were found to be 15 times more likely to develop a visual improvement of at least one line (relative risk = 15; 95 percent confidence interval = 1.5–153.5). No significant differences were noted between the two groups with respect to important covariates.

In summary, this study found that the vision outcomes reported by the Treatment of Age-Related Macular Degeneration With Photodynamic Therapy (TAP) investigators can be reproduced under real-world conditions.

Prospective Study of Intake of Fruits, Vegetables, Vitamins and Carotenoids and the Risk of ARM
Archives of Ophthalmology
2004;122:883–892

Intake of antioxidant vitamins and carotenoids as well as fruits and vegetables was examined in relation to the development of age-related maculopathy in a prospective follow-up study of women in the Nurses’ Health Study and men in the Health Professionals Follow-up Study.

Cho et al. found that fruit intake was inversely associated with the risk of neovascular ARM.

Participants who consumed at least three servings per day of fruits had a pooled multivariate relative risk of 0.64 (95 percent confidence interval = 0.44–0.93, P-value, test for trend = 0.004) compared with those who consumed less than 1.5 servings per day. The results were similar in women and men. However, intakes of vegetables, antioxidant vitamins or carotenoids were not strongly related to either early or neovascular ARM.

In summary, the data from this study suggest a protective role for fruit intake with regard to risk of neovascular ARM.

_______________________________
American Journal of Ophthalmology summaries are written by Thomas J. Liesegang, MD. Archives summaries are written by the lead authors.

To read the full articles, visit www.ajo.com and www.archopht.ama-assn.org.



Round-Up of Other Journals

Bacterial Conjunctival Flora in Diabetic Patients
Cornea
2004;23:136–142

Martins et al. have shown that the presence of diabetic retinopathy signals a higher prevalence of potentially pathogenic bacteria in the conjunctival flora, a finding that may help explain the higher susceptibility in this population to postoperative infection.

The study involved 103 patients from a diabetic retinopathy screening program, and 60 individuals who did not have diabetes.

All participants underwent slit-lamp evaluation, conjunctival scrapings and indirect ophthalmoscopy.

The diabetic group experienced a significantly higher frequency of positive conjunctival cultures (94.18 percent) than those without diabetes (73.33 percent).

Additionally, in the diabetic patient population, those with diabetic retinopathy had a significantly higher frequency of positive cultures than those without retinopathy.

The most common microorganism isolated was the coagulase-negative Staphylococcus, and it was identified more frequently in patients with retinopathy than in those without diabetic retinopathy.

The researchers conclude that if the presence of diabetic retinopathy is, in fact, correlated with a higher prevalence of coagulase-negative Staphylococcus on the conjunctival surface, then retinopathy may serve as a warning sign for an increased risk of endophthalmitis.

An Adjunct to Coronal Computed Tomography in Evaluating Orbital Floor Fractures
Journal of Oral and Maxillofacial Surgery
2004;62:456–459

Can including a single reformatted oblique sagittal view as an adjunct to coronal computer tomography enhance the surgeon’s ability to evaluate and treat orbital floor fractures in patients with orbital trauma? According to a retrospective study conducted by Rake et al., the answer is yes.

The investigators randomly selected 12 midface CT scans of patients with an orbital fracture.

Five surgeons evaluated the CT scans without receiving benefit of a clinical history.

They were asked a series of questions about the fracture, and then asked the same questions after reviewing the adjunct single reformatted oblique sagittal views. They also answered these two questions: “Do you think the oblique view gave you additional information?” and “Would it change your treatment plan?”

Results indicated that the single reformatted oblique sagittal view offered additional information in determining the size and location of the fracture in an anterior-posterior dimension, and also offered help in ascertaining the overall amount of soft tissue displaced from the orbit into the maxillary sinus and status of the inferior rectus muscle. In 18 percent of the responses, the surgeons said that the additional information changed their treatment plan.

The authors conclude that routinely obtaining an adjunct single reformatted oblique sagittal view provides valuable information without subjecting patients to additional radiation and cost.

_______________________________
Round-up is written by Lori Baker Schena and edited by Jose S. Pulido, MD, MS, MBA.

About Us Academy Jobs Privacy Policy Contact Us Terms of Service Medical Disclaimer Site Index