Accuracy of an objective binocular automated phoropter for providing spectacle prescriptions

CLINICAL RELEVANCE

Currently eye examinations are usually based on autorefraction followed by subjective refraction (SR) with a phoropter. An automated phoropter that can also perform autorefraction may facilitate the optometric workflow.

BACKGROUND

The efficiency and feasibility of an objective autorefraction and correction system are assessed by comparing objective refractive measurements with SR on the same subjects and evaluating the visual acuity (VA) values obtained after the objective refractive measurement and correction.

METHODS

Objective autorefraction and correction was performed on 41 subjects using an automated binocular phoropter system. The auto-phoropter performs autorefraction by wavefront measurement and corrects the spherical and cylindrical errors with tunable fluidic lenses while the patient looks at a visual display inside the instrument. The instrument outputs are optometric constants of spherical and cylindrical aberrations. After measurement and automated correction of the refractive errors, the VA values were assessed by having the subjects look at an integrated Snellen chart. The objective measurement results were statistically compared with their SR.

RESULTS

The correlations between SR and objective autorefraction and correction spherical equivalents (M) were 0.98 (0.97-0.99) and 0.96 (0.93-0.98), the vertical Jackson cross cylinder (J0) were 0.96 (0.92-0.98) and 0.95 (0.91-0.97), and the oblique Jackson cross cylinder (J45) were 0.73 (0.55-0.85) and 0.82 (0.69-0.90), for the right and left eyes, respectively, with the 95% confidence interval (CI) values in parentheses. 89.0% of the 82 eyes had at least 6/7.5 VA.

CONCLUSIONS

A significant agreement between the SR and objective autorefraction and correction was observed. An all-objective refractive assessment with instantaneous verification may improve the precision of eye prescriptions and possibly reduce the procedure time.

Intracameral dexamethasone injection in the treatment of cataract surgery induced inflammation: design, development, and place in therapy

Cataract surgery is one of the most commonly performed surgeries worldwide, with nearly 20 million cases annually. Appropriate prophylaxis after cataract surgery can contribute to a safe and quick visual recovery with high patient satisfaction. Despite being the current standard of care, the use of multiple postoperative eye drops can create a significant burden on these patients, contributing to documented and significant non-adherence to the postoperative regimen. Over the past 25 years, there have been a few studies analyzing the use of intracameral dexamethasone (DXM) in controlling inflammation following cataract surgery. This review explores various drug delivery approaches for managing intraocular inflammation after cataract surgery, documenting the strengths and weaknesses of these options and examining the role of intracameral DXM (among these other strategies) in controlling postoperative intraocular inflammation. Intracameral DXM has a particular advantage over topical steroids in possibly decreasing postoperative inflammatory symptoms and objective anterior cell and flare scores. Compared to topical steroids, there may be a slightly less theoretical risk of significant intraocular pressure spikes and systemic absorption. In addition, surveys indicate patients prefer an intraoperative intracameral injection over a self-administered postoperative eye drop regimen. However, there are several adverse effects associated with intracameral DXM delivery that are not seen with the noninvasive topical approach. Although it is unlikely that intracameral DXM will replace topical medications as the standard management for postoperative inflammation, it is seemingly another safe and effective strategy for controlling postoperative inflammation after routine cataract surgery.

Diagnostic Vitrectomy (25-Gauge) in a Case with Intraocular Lymphoma Masquerading as Bilateral Granulomatous Panuveitis

Purpose.

To report a case of intraocular lymphoma, masquerading as bilateral granulomatous panuveitis, and diagnosed after harvesting vitreous specimen with a 25-gauge vitrectomy instrument.

Methods.

A 67-year-old woman presented with bilateral granulomatous uveitis. Visual acuity in both eyes was severely impaired because of severe concurrent cataract and vitreous organization. Sutureless phacoemulsification and posterior chamber intraocular lens implantation combined with 25-gauge diagnostic vitrectomy was performed.

Results.

Cytopathology and immunocytochemistry of the vitreous disclosed a non-Hodgkin B-cell lymphoma despite unremarkable brain MRI, lumbar puncture, bone marrow aspiration, and whole body scan. Visual acuity improved to 20/120 in both eyes.

Conclusions.

Sutureless combined 25-gauge diagnostic vitrectomy, phacoemulsification, and posterior chamber intraocular lens implantation during one-stage surgery was effective in obtaining appropriate vitreous material for cytology in a case of intraocular lymphoma.

Visual system manifestations of Alzheimer's disease

Alzheimer's disease (AD) is an increasingly common disease with massive personal and economic costs. While it has long been known that AD impacts the visual system, there has recently been an increased focus on understanding both pathophysiological mechanisms that may be shared between the eye and brain and how related biomarkers could be useful for AD diagnosis. Here, were review pertinent cellular and molecular mechanisms of AD pathophysiology, the presence of AD pathology in the visual system, associated functional changes, and potential development of diagnostic tools based on the visual system. Additionally, we discuss links between AD and visual disorders, including possible pathophysiological mechanisms and their relevance for improving our understanding of AD.

CENTRAL SEROUS CHORIORETINOPATHY IN POSTMENOPAUSAL WOMEN RECEIVING EXOGENOUS TESTOSTERONE

PURPOSE

Central serous chorioretinopathy (CSR) is a serous detachment of the neurosensory retina commonly associated with male sex, Type-A personality and corticosteroid use. Exogenous administration of androgens and development of CSR in men has been reported. Only one case of CSR in a postmenopausal woman receiving exogenous androgen therapy has been reported. The authors describe three cases of chronic CSR in postmenopausal women receiving exogenous testosterone therapy.

METHODS

Diagnosis was based on characteristic clinical, fluorescein angiographic, and optical coherence tomography findings. The three women were being treated with exogenous testosterone and progesterone therapy for symptoms of menopause and libido loss.

RESULTS

Average age at presentation was 54.7 years (53-56 years), average duration of exogenous androgen use was 61 months (36-87 months), with average 19.7-month follow-up. Resolution of symptoms seemed correlated with cessation of androgen use despite treatment with oscillatory photodynamic therapy and intravitreal pharmacotherapy with antivascular endothelial growth factor agents.

CONCLUSION

Exogenous testosterone is increasingly prescribed for menopausal symptoms and libido loss. Treatment with oscillatory photodynamic therapy, supplemental bevacizumab intravitreal pharmacotherapy, and cessation of exogenous androgen therapy was successful in three cases of chronic, therapy-resistant CSR. Ophthalmologists should inquire about androgen usage in patients who present with CSR, especially in the setting of therapy resistance.

Two Doses of Intravitreal Ziv-Aflibercept versus Bevacizumab in Treatment of Diabetic Macular Edema: A Three-Armed, Double-Blind Randomized Trial

PURPOSE

To compare the efficacy of 2 doses of intravitreal ziv-aflibercept (IVZ) with intravitreal bevacizumab (IVB) in the treatment of center-involved diabetic macular edema (DME) at 12 weeks.

DESIGN

Three-armed, double-blind, randomized clinical trial.

PARTICIPANTS

Eyes with center-involved DME.

METHODS

In this trial, 123 eyes with DME were randomly assigned to 3 injections of 1.25 mg IVZ, 2.5 mg IVZ, and 1.25 mg IVB every 4 weeks. Complete ophthalmologic examination and central macular thickness (CMT) measurement by optical coherence tomography were performed every 4 weeks up to 12 weeks.

MAIN OUTCOME MEASURES

Change in best-corrected visual acuity (BCVA) at 12 weeks.

RESULTS

Although no significant difference was evident between the 2 ziv-aflibercept groups at 12 weeks, the BCVA change was significantly better in the ziv-aflibercept 1.25 mg group than in the IVB group at the 12-week visit (P = 0.021). In regard to CMT changes, there was no significant difference between the 2 ziv-aflibercept groups; however, a significantly greater reduction in CMT was observed in the ziv-aflibercept 2.5 mg group compared with the IVB group at 12 weeks (P = 0.037). Subgroup analysis disclosed no difference in BCVA outcomes at 12 weeks among the groups in the eyes with baseline BCVA ≥20/50. In the eyes with baseline BCVA <20/50, the improvement was significantly better at 12 weeks in the ziv-aflibercept 1.25 mg group compared with the IVB group (P = 0.011).

CONCLUSIONS

The 12-week results of this trial disclosed that both 1.25 mg and 2.5 mg doses of IVZ and IVB demonstrated BCVA improvement over baseline in the treatment of center-involved DME. However, a stronger effect of IVZ compared with IVB in terms of both visual acuity improvement and macular thickness reduction was detected in the eyes with initial BCVA <20/50. Longer-term efficacy and safety data will be needed to understand the role for this drug in practice.

Intravitreal bevacizumab injection alone or combined with triamcinolone versus macular photocoagulation in bilateral diabetic macular edema; application of bivariate generalized linear mixed model with asymmetric random effects in a subgroup of a clinical trial

PURPOSE

To compare the efficacy of intravitreal bevacizumab (IVB) injection alone or with intravitreal triamcinolone acetonide (IVB/IVT) versus macular photocoagulation (MPC) in bilateral diabetic macular edema (DME).

METHODS

In this study we revisited data from a subset of subjects previously enrolled in a randomized clinical trial. The original study included 150 eyes randomized to three treatment arms: 1.25 mg IVB alone, combined injection of 1.25 mg IVB and 2 mg IVT, and focal or modified grid MPC. To eliminate the possible effects of systemic confounders, we selected fellow eyes of bilaterally treated subjects who had undergone different treatments; eventually 30 eyes of 15 patients were re-evaluated at baseline, 6, 12, 18, and 24 months. Using mixed model analysis, we compared the treatment protocols regarding visual acuity (VA) and central macular thickness (CMT).

RESULTS

Improvement in VA in the IVB group was significantly greater compared to MPC at months 6 and 12 (P = 0.037 and P = 0.035, respectively) but this difference did not persist thereafter up to 24 months. Other levels of VA were comparable at different follow-up intervals (all P > 0.05). The only significant difference in CMT was observed in favor of the IVB group as compared to IVB/IVT group at 24 months (P = 0.048).

CONCLUSION

Overall VA was superior in IVB group as compared to MPC up to 12 months. Although the IVB group showed superiority regarding CMT reduction over 24 months as compared to IVB/IVT group, it was comparable to the MPC group through the same period of follow up.

Spectral-domain optical coherence tomography appearance of a retinal nematode

A 65-year-old man presented with decreased visual acuity in his left eye of 10 days' duration. Ocular examination revealed visual acuity of 20/200 in the left eye caused by a visible retinal nematode (roundworm) located close to the fovea. Spectral-domain optical coherence tomography imaging showed the nematode in the retinal nerve fiber layer. The patient was followed up without treatment, and the nematode disappeared spontaneously after 5 weeks. Visual acuity in the affected eye improved to 20/25.

A minimally invasive jet injector for intravitreal and subconjunctival injection

BACKGROUND AND OBJECTIVE

To evaluate a minimally invasive injector for intravitreal and subconjunctival administration of medications.

MATERIALS AND METHODS

The device has a microneedle that communicates with an internal formulation chamber. A piercing depth-limiting flange restricts microneedle penetration to a depth of less than 1 mm and defines the location of the pars plana from the limbus. The jet injector creates a force of up to 1,000 psi, forcing the medication through the remaining sclera/choroid thickness. The device was tested in 28 enucleated rabbit eyes and 9 experimental and 4 control rabbit eyes to define jet pressure for subconjunctival and intravitreal injection.

RESULTS

Injection pressures of 76 to 156 psi were needed for subconjunctival injection and 974 psi for intravitreal injection. Clinical and histologic examinations did not reveal damage to intraocular structures.

CONCLUSION

The semi-automated jet injector facilitated intravitreal/subconjunctival injection. The microneedle-assisted jet injector minimized the risk of wet injection by anchoring the microneedle in the sclera.

SD-OCT features of laser pointer maculopathy before and after systemic corticosteroid therapy

The authors report spectral-domain optical coherence tomography findings of laser pointer-induced maculopathy in a 25-year-old man after accidental laser pointer exposure of less than 1 second. The Class 3R laser pointer (output wavelength 532 nm and output power 3.5 to 4.5 mW [continuous wave]) had U.S. Food and Drug Administration certification. One day after exposure, he had visual blurring and metamorphopsia of his right eye. He was treated with a systemic high-dose corticosteroid. Spectral-domain optical coherence tomography disclosed a hyperreflective band in the foveal region. After 1 week of treatment, disappearance of hyperreflectivity was observed on spectral-domain optical coherence tomography. At 6 months, residual disruption of the outer retinal layer at the fovea remained unchanged. Spectral-domain optical coherence tomography was a useful and sensitive tool for evaluating retinal damage and subsequent resolution after treatment.

Spectral-domain optical coherence tomography features of mild and severe acute solar retinopathy

Photochemical/thermal retinal damage that results from unprotected solar eclipse viewing has vague presentations and sometimes misleading diagnosis, especially in cases with unclear history. Spectral-domain optical coherence tomography (SD-OCT) is a non-invasive imaging technique useful in differential diagnosis that can reveal characteristic foveal alterations in solar retinopathy to an unprecedented quasi histologic level. The authors present high-resolution SD-OCT findings correlated with clinical findings in three eyes of two cases with acute solar retinopathy. SD-OCT can precisely define the site and extent of damage in acute solar retinopathy. In mild forms, damage may be limited to the outer retina with inner segment/outer segment disruption. In severe forms, full thickness macular damage may be seen. Advances in retinal imaging have improved our ability to provide precise correlation with clinical presentation and prognosis.

Oscillatory photodynamic therapy for choroidal neovascularization and central serous retinopathy; a pilot study

PURPOSE

To report the preliminary results of oscillatory photodynamic therapy (OPDT) for choroidal neovascularization (CNV) and central serous retinopathy (CSR).

METHODS

This study included 7 eyes of 6 patients with CSR (2 eyes), idiopathic CNV (2 eyes), CNV due to age-related macular degeneration (AMD) (2 eyes), and peripapillary CNV secondary to presumed ocular histoplasmosis syndrome (1 eye). Intravenous verteporfin (6 mg/m(2) body surface area) was infused over 10 minutes followed by oscillating laser (wavelength 689 nm) covering slightly beyond the entire lesion. An Area Centralis lens was applied and laser was delivered (600 mW/cm(2) fluence rate and 50 J/cm(2) dose). Intravitreal bevacizumab and dexamethasone combination therapy was used with OPDT in 4 eyes with CNV; intravitreal dexamethasone and triamcinolone acetonide were injected in the other eye with CNV. Clinical examination, funduscopy, fluorescein angiography, and optical coherence tomography (OCT) were performed at baseline and after treatment.

RESULTS

After mean follow-up of 7.1±5.1 months, visual acuity improved from 0.87±0.69 logMAR (20/160) to 0.60±0.65 logMAR (20/80) (P = 0.027); central foveal thickness decreased from 322±62.1 to 240.7±34.8 microns as measured by OCT (P = 0.018). Fluorescein angiography and OCT demonstrated cessation of vascular leakage, and resolution of hemorrhage and subretinal fluid in all eyes. No adverse events or recurrence were noted.

CONCLUSION

OPDT was effective in treating CNV lesions and CSR. OPDT may be an improvement on standard PDT due to reduced side effects, thermal damage and scarring.

Globe-fixation system for animal eye practice

We designed a globe-fixation system for use with animal eyes for surgical skills training. The system core is a cup with an adjustable aperture. Vacuum is exerted through the cup to capture the globe at the preequatorial region. The cup rides over a hollow base, sliding on its opening spurs. A ballast is screwed to the end of the thread of the cup to create tactile feedback and create a tendency to return to the primary position. The system provides optimum versatility for the practice of anterior segment procedures, namely stability, rotation, a tendency to return to the primary position, globe pressure adjustability, and a modifiable orbit size.

FINANCIAL DISCLOSURE

Disclosures are found in the footnotes.

Visual outcomes in five different approaches for treatment of central retinal vein occlusion

BACKGROUND AND OBJECTIVE

Four treatment methods for central retinal vein occlusion were compared with its natural course.

PATIENTS AND METHODS

In this partially prospective, comparative, interventional case series on 63 eyes with central retinal vein occlusion, five approaches were compared: intravitreal triamcinolone injection; radial optic neurotomy; combined radial optic neurotomy and intraocular triamcinolone injection; combined internal limiting membrane peeling, radial optic neurotomy, and intraocular triamcinolone; and observation.

RESULTS

Final visual acuity in the intravitreal triamcinolone group was better compared with the observation (P = .025), radial optic neurotomy (P = .037), combined radial optic neurotomy/intraocular triamcinolone injection (P = .401), and combined internal limiting membrane peeling, radial optic neurotomy, and intraocular triamcinolone injection (P = .023) groups. However, after adjustment for baseline visual acuity, the only treatment method with significant visual acuity improvement in relation to the observation group was the combined radial optic neurotomy/intraocular triamcinolone injection (P = .025, .023, and .054 at 1, 3, and 6 months, respectively).

CONCLUSION

Among the five different approaches analyzed in this study, combined radial optic neurotomy and intraocular triamcinolone injection may provide a better visual outcome in the management of central retinal vein occlusion.

Three-Dimensional OCT Features of Perfluorocarbon Liquid Trapped Under the Fovea

Two patients with perfluorocarbon liquid (PFCL) trapped under the fovea after vitreoretinal surgery for repair of rhegmatogenous retinal detachment were reported. PFCL was used to flatten the retina intraoperatively. Postoperatively, a bubble of PFCL was trapped under the fovea and was removed surgically in both patients. Three-dimensional and orthogonal optical coherence tomography (OCT) features in both cases are reported. Three-dimensional OCT features in our two cases were retinal pigment epithelium (RPE) pigment disorganization, disruption of both external limiting membrane backreflection line and reflectivity of the photoreceptor inner and outer segment junction, and hyperreflectivity at the base of the PFCL bubble corresponding to the zone of interface of PFCL and damaged RPE. Trapped subfoveal PFCL should be removed surgically as soon as possible to prevent structural retinal damage. Spectral domain OCT is a useful tool to demonstrate subclinical structural damage of the neurosensory retina and RPE.

Interaction of intravitreal combination drugs and the effect on the targeted site

BACKGROUND

After evaluating experimentally the diffusion processes in the retina using peroxidase as a tracer material (previously published work), we found that junctional complexes of the retinal pigment epithelium and retinal capillaries were the major impediment to free diffusion between the retina and choroidal-retinal blood vessels. These experiments indicated that to achieve high therapeutic concentrations of medications inside the eye, it was necessary to administer them by intravitreal injection. Soon after initial experimental work the necessity of combining antibiotics or antibiotics with steroids became obvious. As the use of intravitreal injection grew over the last 2 decades, so did the concept of combination therapy.

METHODS

This review describes potential causes of drug-drug interaction and the rationale for combination therapy when injected into the vitreous cavity, encompassing publications between 1971 and 2008.

RESULTS

We describe the conditions that can cause physical-chemical interactions between the medications and the need for combination therapy for treatment of various intraocular disease processes.

CONCLUSIONS

The intravitreal injection of medication and their combinations has become a part of standard care for many diseases of the retina and choroid. This article reviews the potential interaction of nontoxic doses of medications when injected simultaneously in the vitreous cavity, and disease processes that are now treated with these combination therapies.

Intravitreal injection of therapeutic agents

BACKGROUND

Intravitreal injection (IVI) with administration of various pharmacological agents is a mainstay of treatment in ophthalmology for endopthalmitis, viral retinitis, age-related macular degeneration, cystoid macular edema, diabetic retinopathy, uveitis, vascular occlusions, and retinal detachment. The indications and therapeutic agents are reviewed in this study.

METHODS

A search of the English, German, and Spanish language MEDLINE database was conducted. A total of 654 references spanning the period through early 2008 were individually evaluated.

RESULTS

The advantage of the IVI technique is the ability to maximize intraocular levels of medications and to avoid the toxicities associated with systemic treatment. Intravitreal injection has been used to deliver several types of pharmacological agents into the vitreous cavity: antiinfective and antiinflammatory medications, immunomodulators, anticancer agents, gas, antivascular endothelial growth factor, and several others. The goal of this review is to provide a detailed description of the properties of numerous therapeutic agents that can be delivered through IVI, potential complications of the technique, and recommendations to avoid side effects.

CONCLUSION

The IVI technique is a valuable tool that can be tailored to the disease process of interest based on the pharmacological agent selected. This review provides the reader with a comprehensive summary of the IVI technique and its multitude of uses.

Management of Pediatric Vogt-Koyanagi- Harada (VKH)-Associated Panuveitis

PURPOSE

To assess the clinical course, determine the efficacy and safety of oral methotrexate in the control of intraocular inflammation, and evaluate the outcomes of lensectomy-vitrectomy and goniosynechiolysis on pediatric VKH-associated panuveitis.

DESIGN

Retrospective non-comparative interventional case series.

PARTICIPANTS

Ten patients (20 eyes) with pediatric VKH-associated panuveitis (onset of disease at age 14 years or younger).

INTERVENTION

Stepwise medical treatment consisted of oral prednisolone (0.5-1 mg/kg), supplemented by oral methotrexate (5-7.5 mg/wk) in refractory cases. Surgical intervention was performed for complications such as visually significant cataracts and secondary glaucoma and included pars plana lensectomy-vitrectomy and peripheral anterior synechiolysis in a one-stage procedure.

MAIN OUTCOME MEASURES

Control of inflammation, corticosteroid requirement, visual acuity, and intraocular pressure (IOP).

RESULTS

Ten consecutive patients with a minimum follow-up duration of six months were analyzed. All patients were initially treated with oral corticosteroids; methotrexate was additionally required in six subjects. In all eyes, inflammation decreased and vision was preserved or improved. Side effects of methotrexate were mild and transient. Nine eyes of five patients underwent combined lensectomy and vitrectomy. The procedure was successful in all eyes without any exacerbation of inflammation. Eight eyes had elevated IOP, six of which underwent peripheral anterior synechiolysis at the time of lensectomy-vitrectomy. IOP was controlled after the procedure in all eyes with timolol only. Overall, final visual acuity was=20/40 in 30% of the eyes and<20/200 in only 20%.

CONCLUSIONS

Pediatric VKH-associated panuveitis seems to follow an aggressive course; the development rate of cataracts and secondary glaucoma seems to be high. Oral methotrexate is a safe and effective adjunct and displays steroid-sparing properties in the control of inflammation. Surgical interventions including peripheral anterior synechiolysis in addition to pars plana lensectomy and vitrectomy may be effective in controlling IOP in eyes with cataract and glaucoma.

PRECIS

Vision may be preserved in pediatric VKH panuveitis using steroids and methotrexate for the control of inflammation, lensectomy-vitrectomy for visual improvement, and synechiolysis for IOP control.

Simultaneous multiple branch retinal artery occlusions after diagnostic cardiac catheterization

PURPOSE

We describe a 53-year-old man with a decrease in visual acuity in the left eye 2 weeks after diagnostic cardiac catheterization.

DESIGN

Interventional case report.

METHODS

A 53-year-old man with a decrease in visual acuity in the left eye 2 weeks after diagnostic cardiac catheterization underwent ophthalmoscopic, angiographic, and laboratory evaluations. Both funduscopy and fluorescein angiography confirmed the diagnosis of simultaneous multiple branch retinal artery occlusions in the left eye.

RESULTS

The left eye had a mildly positive (1+) relative afferent pupillary defect. Slit-lamp biomicroscopy was unremarkable except for 2+ nuclear cataract bilaterally. Intraocular pressure was 12 mmHg in the right eye and 11 mmHg in the left eye by applanation tonometry. Funduscopy revealed a normal right eye.

CONCLUSION

This case report of multiple branch retinal artery occlusions due to cholesterol embolus after diagnostic cardiac catheterization is extremely rare. Visual symptoms after cardiac catheterization should alert both ophthalmologists and cardiologists to this potential post-cardiac catheterization complication.

Histopathologic evaluation of optic neurotomy with microvitreoretinal blade or excimer laser in cadaver eyes

BACKGROUND AND OBJECTIVE

To evaluate histopathologic features of optic neurotomy with microvitreoretinal (MVR) blade or excimer laser.

MATERIALS AND METHODS

Optic neurotomy was performed in 11 cadaver eyes using a 20-gauge MVR blade and 3 cadaver eyes with pulsed xenon chloride excimer laser. Hematoxylin-eosin stained slides were used to evaluate the posterior segments of the globes, including the optic nerve head.

RESULTS

No eyes in the MVR group had scleral macroscopic or microscopic perforation and there was no injury to the central retinal vein or artery. The distance between the neurotomy site and the central retinal vessels ranged from 50 to 500 microm at all histologic levels in 10 eyes and was approximately 10 microm in two histologic sections and 200 microm in a third section in 1 eye. Intraneural hemorrhage was found in 11% of eyes. Neurotomy was successful in 2 of 3 eyes with the excimer laser and no neurotomy was evident on sectioning in the third eye due to cloudy media.

CONCLUSIONS

Optic neurotomy with an MVR blade was an effective procedure for scleral outlet relaxation in cadaver eyes, with no significant surgical complications. This preliminary study also demonstrates that the excimer laser can make non-mechanical cuts with relative ease and reliability.

Triamcinolone acetonide in ocular therapeutics

Triamcinolone acetonide has been effectively used in ocular therapeutics for over 50 years. Its use has increased dramatically in recent years for periocular and intraocular treatment of retinal vasculature disease and uveitis. This comprehensive review discusses the pharmacokinetics of triamcinolone acetonide and summarizes its uses in a number of diseases, both intraocular and extraocular. It discusses side effects and their management. Finally, it discusses the controversy over its use.

[Retinal toxicity of intravitreal doxycycline. A pilot study]

OBJECTIVE

To assess the retinal toxicity of varying concentrations of intravitreally administered doxycycline, a member of tetracycline family.

METHODS

Fourteen New Zealand albino rabbits, divided into 5 groups, were used for this study. The initial concentration of doxycycline (100 mg) was titrated using 5% dextrose solution to the following concentrations in a volume of 0.1 ml: 2000 microg, 1000 microg, 500 microg, 250 microg, 125 microg, and 62.5 microg. Each concentration was injected into 2 rabbit eyes. Two control eyes received 0.1 ml of 5% dextrose solution. All animals were examined before and after injection using indirect ophthalmoscopy and slit-lamp biomicroscopy. Electroretinography (ERG) was performed on all animals prior to the intravitreal injection and 2 weeks post-injection. The animals were re-examined at this time by indirect ophthalmoscopy and slit-lamp biomicroscopy and were then subjected to euthanasia. Their eyes were enucleated and examined using light microscopy.

RESULTS

The doxycycline injected group exhibited significant decreases in ERG of the eyes injected with 2000 microg, 1000 microg, 500 microg, and 250 microg/0.1 ml. No significant changes in the ERG were observed following the injection of lesser concentration levels. There were no signs of retinal toxicity on slit-lamp examination, indirect ophthalmoscopy, or light microscopy in all the eyes injected with doxycycline concentrations of 125 microg or lower.

CONCLUSIONS

Doxycycline injected intravitreally appeared safe at concentrations of 125 microg/0.1 ml or less in albino rabbits. Intravitreal doxycycline may be beneficial, and is an inexpensive alternative drug which could be used in the treatment of bacterial endophthalmitis particularly against resistant Staphylococcus aureus organisms.

Pars plana Ahmed valve implant and vitrectomy in the management of neovascular glaucoma

BACKGROUND AND OBJECTIVE

To evaluate the efficacy and safety of the pars plana Ahmed glaucoma valve (New World Medical, Inc., Rancho Cucamonga, CA) implant combined with pars plana vitrectomy and panretinal photocoagulation for the management of neovascular glaucoma in patients with vitreous hemorrhage.

PATIENTS AND METHODS

The records of 18 eyes of 17 consecutive patients with neovascular glaucoma who had undergone pars plana vitrectomy and pars plana Ahmed valve implant were evaluated. The patients were observed for a mean time of 14.2 months (range, 6 to 28 months).

RESULTS

Mean preoperative intraocular pressure with oral and two or three topical antiglaucoma medications was 53.3 +/- 10 mm Hg, and mean postoperative intraocular pressure without oral antiglaucoma medications was 16.3 +/- 7.1 mm Hg (P < .0001) at the final visit. Overall success rate was 72.2%, defined as an intraocular pressure of 5 to 21 mm Hg with or without antiglaucoma medication. A postoperative hypertensive phase occurred in 7 patients (38.8%), of which all but one responded to medical therapy. Visual acuity was stabilized or improved in 77.7% of the eyes. There was one case of each of the following adverse events: mild vitreous cavity hemorrhage, hypotony, choroidal effusion, epiretinal membrane, corneal edema, and corneal ulcer. Two cases developed phthisis bulbi and lost light perception.

CONCLUSIONS

Pars plana vitrectomy and Ahmed valve implantation seems to be a viable surgical modality in the management of neovascular glaucoma and coexisting posterior segment pathology with a relatively low rate of serious permanent postoperative complications.

Medulloepithelioma masquerading as chronic anterior granulomatous uveitis

CASE REPORT

We report a rare clinical case of unilateral ciliary body teratoid medulloepithelioma presented first with infantile cataract, subsequently masquerading as chronic granulomatous anterior uveitis, followed by appearance of a tumour over the iris surface.

COMMENTS

Diagnosis of the tumour in the early stages allows proper management and avoids enucleation.

The effect of intravitreally injected povidone-iodine on Staphylococcus epidermidis in rabbit eyes

PURPOSE

Firstly, the aim of this study was to determine the maximally tolerated dose of intravitreally injected povidone-iodine (PVP-I). A second aim was to test the efficacy of PVP-I on rabbit eyes infected intravitreally with Staphylococcus epidermidis.

METHODS

Phase I of the study used 16 New Zealand albino rabbits, divided into 4 groups (n=4 each). Animals were anesthetized and intravitreally injected with 0.1 mL of 50, 100, 200, or 400 micrograms (microg) of PVP-I in 1 eye, and with saline in the other. The animals were examined at days 1, 7, and 14, using indirect ophthalmoscopy and slit-lamp biomicroscopy; electroretinography (ERG) was performed before treatment and prior to euthanization. Histological preparations were examined to determine retinal damage. Phase II of the study divided 20 New Zealand albino rabbits into 4 groups (n=5 each). Animals were anesthetized and injected with 0.1 mL of S. epidermidis containing 3030 colony forming units (CFU) in 1 eye and saline in the other. Seven (7) h later, animals were treated with 0.1 mL of 20, 50, and 100 microg of PVP-I, or no treatment. Bacterial concentrations from extracted vitreous were determined 2 days following infection. Results were analyzed for statistical significance, using the Student t test and analysis of variance, and histologic preparations assessed the presence of endophthalmitis.

RESULTS

Phase I of the study observed no retinal damage at any of the concentrations studied, as noted by indirect ophthalmoscopy, slit-lamp biomicroscopy, ERG, and histologic exam. Phase II of the study showed no statistical difference in bacterial counts between treatment and control groups. All infected eyes went on to develop endophthalmitis, as observed by indirect ophthalmoscopy and histologic preparations.

CONCLUSIONS

These results suggest that 400_g of PVP-I can be tolerated intravitreally in rabbit eyes with no noticeable damage over a 14-day period. Results further showed that 100 microg of intravitreally injected PVP-I has no statistically significant effect on rabbit eyes injected intravitreally with 3030 CFU of S. epidermidis.

Prophylaxis of acute posttraumatic bacterial endophthalmitis: a multicenter, randomized clinical trial of intraocular antibiotic injection, report 2

OBJECTIVE

To evaluate the efficacy of intraocular gentamicin sulfate and clindamycin in the prevention of acute posttraumatic bacterial endophthalmitis following penetrating eye injuries.

METHOD

We conducted a multicenter, randomized, double-masked controlled trial of 346 eyes with penetrating eye injury. Following primary repair, eyes were randomized to intracameral or intravitreal injection of 40 microg of gentamicin sulfate and 45 microg of clindamycin (cases) vs balanced salt solution (controls).

MAIN OUTCOME MEASURE

Occurrence of endophthalmitis within 2 weeks.

RESULTS

Endophthalmitis occurred in 8 (2.3%) of 167 eyes in the control group and only in 1 (0.3%) of 179 eyes in the case group (P = .04; odds ratio, 8.93 [95% confidence interval, 1.11-71.43]). In eyes with an intraocular foreign body, endophthalmitis developed in 7 of 25 control eyes and in none of 27 eyes receiving antibiotics. However, in eyes without an intraocular foreign body, endophthalmitis developed in 1 of 142 eyes and 1 of 152 eyes in the 2 groups, respectively (P value for interaction = .04). Intravitreal injection was superior to intracameral injection in preventing endophthalmitis (P value for interaction = .01). Vitreous culture results were positive in 6 (67%) of 9 eyes with endophthalmitis.

CONCLUSION

Intraocular gentamicin and clindamycin are effective in the prevention of acute posttraumatic bacterial endophthalmitis in eyes with retained intraocular foreign body.

APPLICATION TO CLINICAL PRACTICE

Prophylaxis of traumatic endophthalmitis.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00398658.

Identification of intraretinal neovascularization by high-speed indocyanine green angiography in idiopathic perifoveal telangiectasia

Rapid advances in imaging technology have dramatically improved our understanding of the flow patterns of intraretinal circulation in normal and diseased states. To identify the angiographic features and flow pattern of retinal circulation in a patient with type 2 idiopathic perifoveal telangiectasia, dynamic simultaneous high-speed videoangiography using confocal scanning laser ophthalmoscopy was performed. This diagnostic tool provides enhanced anatomic resolution of retinal arterioles otherwise poorly defined by regular fluorescein and static indocyanine green angiography. High-speed indocyanine green angiography demonstrated dynamic flow abnormalities such as intraretinal neovascular complex and retino-retinal anastomosis in idiopathic perifoveal telangiectasia.

Threshold parameters for choroidal vessel closure with the photosensitizer, lambda 27

OBJECTIVE

To determine the threshold photodynamic therapy parameters, required for choroidal vessel closure, with the photosensitizer, Lambda 27, in Dutch belted rabbits, using fluorescein angiography and histopathology.

DESIGN

A pre-clinical experiment.

PLACE AND DURATION OF STUDY

Department of Ophthalmology at the Tulane University Health Sciences Center, between June 2001 - July 2002.

PATIENTS AND METHODS

Dutch belted rabbits were divided into two groups. The first group was injected intravenously with an aqueous solution of Lambda 27 at 1mg/kg. Saline was injected intravenously into the second group (controls). Approximately 5 minutes after injection of Lambda 27, a diode laser, mounted on Zeiss 30 SL-M slit lamp, emitting light at a wavelength of 719 nm was used to apply photodynamic therapy to the fundus. Lesions were placed on the choroid of the rabbits at a fixed spot size of 1.5 mm, using powers ranging from 50 to 120 mW, for a duration of 5 to 80 seconds. Choroidal vessel closure was documented by fluorescein angiography, the following day, and by light microscopy, after the animals were sacrificed.

RESULTS

Choroidal vessel closure was documented using fluorescein angiography for all of the lesions placed at fluence of 22.7 J/cm2 and above. Histopathology also confirmed this finding. No choroidal vessel closure was seen in the rabbits treated with fluences less than 22.7 J/cm2 or in the control group.

CONCLUSION

This experiment establishes threshold parameters for choroidal vessel closure using the photosensitizer, Lambda 27.

Surgical management of retinal detachment in highly myopic eyes with macular hole

BACKGROUND AND OBJECTIVES

To evaluate the visual and anatomical outcomes of surgery for retinal detachment due to macular hole in highly myopic eyes with pronounced posterior staphyloma.

PATIENTS AND METHODS

Data for all patients with high myopia who underwent surgery for retinal detachment resulting from macular hole from 1993 to 2002 in one hospital were evaluated. Patient characteristics, best-corrected visual acuity preoperatively and at last examination, surgical technique, anatomical success, and follow-up period were extracted and analyzed statistically.

RESULTS

Twenty-six of the 27 patients (28 eyes) were female (96%) with a mean age of 59.8 years; mean follow-up was 17.3 months. Mean axial length was 29.1+/-2.74 mm; mean myopia was -16.4 +/- 3.1 diopters. Marked posterior staphyloma was detected in 71%. Seven eyes had undergone failed scleral buckling as the primary procedure; intravitreal SF6 injection was the primary procedure in 12 eyes. Twenty-three eyes underwent deep vitrectomy with use of high viscosity silicone oil. Overall anatomical success was achieved in 92.9% (26 of 28 eyes); 78.6% had visual improvement.

CONCLUSIONS

Vitreous surgery combined with other necessary adjunct procedures such as membrane peeling and use of retinal tamponade, as a primary or a secondary procedure, seems to be successful in achieving retinal reattachment in eyes with macular hole and posterior staphyloma.

Inhibition of corneal angiogenesis by ascorbic acid in the rat model

PURPOSE

To evaluate the effect of topically administered ascorbic acid on experimentally induced corneal neovascularization in the rat model.

MATERIALS AND METHODS

Corneal chemical cauterization of 72 eyes in Long-Evans male rats was performed using silver nitrate/potassium nitrate sticks. Nine groups of eight eyes were used to evaluate eight concentrations of ascorbic acid with one group of eight eyes serving as a control. Topical instillation of 100 mg/ml non-pH-neutralized ascorbic acid was performed in one group while the remaining seven groups were evaluated using pH-neutralized ascorbic acid in concentrations of 100 mg/ml, 50 mg/ml, 10 mg/ml, 5 mg/ml, 1 mg/ml, 500 microg/ml, and 250 microg/ml.

RESULTS

The percentage of corneal neovascularization and burn stimulus score was determined for all the eyes. The means of percent of corneal neovascularization in ascorbic acid 100 mg/ml (non-neutralized), 100 mg/ml, 50 mg/ml, 10 mg/ml, 5 mg/ml, 1 mg/ml, 500 microg/ml, 250 microg/ml, and control group were 17.50 +/- 12.80 (p = 0.001), 17.00 +/- 19.30 (p = 0.001), 15.25 +/- 13.26 (p = 0.001), 17.62 +/- 11.89 (p = 0.001), 28.87 +/- 23.08 (p = 0.001), 29.62 +/- 16.91 (p = 0.001), 60.12 +/- 8.50 (p = 0.04), 65.62 +/- 2.26 (p = 0.185), and 68.25 +/- 4.06, respectively (Tables 1 and 2). All animals had a burn score of 2+ or higher (Table 1).

CONCLUSION

Ascorbic acid applied in a topical solution appears to inhibit corneal neovascularization in the rat model of inflammatory neovascularization in concentrations in a dose-dependent manner. The optimal dose-effect relation was in our model found in concentrations between 1 mg and 500 microg/ml. At concentrations below 500 microg/ml there was no statistically significant inhibition in the degree of corneal neovascularization compared to control.

Intravitreal Toxicity of High-Dose Etanercept

PURPOSE

The aim of this study was to evaluate the retinal toxicity of high-dose intravitreal etanercept, a U.S. Food and Drug Administration-approved anti-inflammatory drug, in the rabbit model.

METHODS

Twenty (20) New Zealand albino rabbits were divided into 5 groups (n=4); eyes in each group were intravitreally injected with one of the following doses of etanercept: 125 microg, 250 microg, 500 microg, 1 mg, or 2.5 mg. One (1) eye in each animal was used for the study dose; the fellow eye was injected with buffered sterile saline as a control. All animals were examined using indirect ophthalmoscopy and slit-lamp biomicroscopy before and after intravitreal injection and at days 1, 7, and 14. Electroretinography (ERG) was performed on all animals before intravitreal injection and 14 days after injection. The animals were euthanized on day 14. Histological preparations of the enucleated eyes were examined with light microscopy for retinal toxicity.

RESULTS

Clinical examination, histological evaluation, and ERG results of all 5 groups demonstrated no signs of retinal toxicity.

CONCLUSIONS

Intravitreal doses as high as 2.5 mg of etanercept did not cause retinal toxicity. Intravitreal doses of up to 2.5 mg of etanercept may provide a more potent, prolonged effect than the lower doses previously recommended.

Intraocular Biodistribution of Mono-L-aspartyl Chlorin e6 in a Primate Choroidal Neovascularization Model

BACKGROUND AND OBJECTIVE

To describe the biodistribution of a hydrophilic sensitizer, mono-L-aspartyl chlorin e6 (NPe6), in a primate model of choroidal neovascularization (CNV).

MATERIALS AND METHODS

NPe6 (25 mg/kg) and indocyanine green (ICG, 15 mg/kg) were intravenously administered simultaneously in monkeys with laser-induced CNVs. Eyes were enucleated and examined by fluorescence microscopy immediately, 20 minutes, and 1, 4, and 24 hours after dye injection.

RESULTS

Fluorescence peaked in retinal vessels immediately after dye administration; rapid washout began 1 hour postinjection. In contrast, experimental CNV demonstrated little fluorescence immediately after injection, with increased intensity at later time points. Peak dye fluorescence in CNV occurred 1 hour following dye injection. NPe6 fluorescence diminished rapidly and washed out completely by 24 hours. The dye accumulation and retention pattern of ICG dye resembled that of NPe6.

CONCLUSIONS

This study demonstrated the selective accumulation of NPe6 photosensitizer and ICG dye within experimental CNV and rapid clearance from the circulation and retinochoroidal tissue.