Earl R. Crouch

Management of posterior lenticonus complicated by unilateral cataract.

We studied 21 patients with 23 eyes with posterior lenticonus. Twenty-one of the eyes developed progressive cataractous changes that required lens aspiration in 19 eyes when vision reduction was 6/30 (20/100) or less. The inherent weakness of the diaphanous portion of the posterior lens capsule contributed to disruption of the normal lamellar arrangement of the lens fibers resulting in cataractous changes. Amblyopia was the most significant visual problem associated with posterior lenticonus. Fifteen of the 19 operated eyes in this study were amblyopic and nine of the 15 were improved to 6/15 (20/50) or better vision with occlusion therapy, after surgical aspiration of the cataractous lens and contact lens therapy.

Bilateral hypermetropic amblyopia

A retrospective analysis was performed on the records of 184 children who had hyperopia of at least 4.0 diopters in each eye to see if bilateral amblyopia was more than just a rare occurrence and to evaluate how well it responded to treatment. Twelve patients were found to have bilateral amblyopia of 20/50 or worse. The mean age at diagnosis was four and a half years (two and a half to six and a half) and mean follow-up was 22 months (five months to seven years, four months). Ten of 12 patients showed improvement of vision to 20/40 or better in both eyes. Treatment consisted of full cycloplegic correction in all cases. Six patients had accommodative esotropia but this did not account for the bilateral nature of the amblyopia. Bilateral amblyopia should be considered in patients with large amounts of hyperopia. It responds well to treatment with standard amblyopia therapy.

Management of traumatic hyphema : Therapeutic options

1. To review the characteristics, ocular findings, and complications of traumatic hyphema. 2. To examine the preferred therapeutic options in traumatic hyphema, especially as they relate to prevention of secondary hemorrhage, and final visual acuity. 3. To examine the indications for surgical intervention in traumatic hyphema.

Finite element model of cornea deformation

Cornea surgeons have observed that changes in cornea curvature can follow cataract surgery and cause astigmatism. The placement of surgical incisions has been shown to influence these curvature changes. Though empirical data has been collected about this phenomenon, a biomechanical model has not been employed in predicting post-surgical outcomes. This work implemented an incised finite element model of the eye to investigate factors influencing corneal shape after surgery. In particular, the effects of eye muscle forces and intra-ocular pressure were simulated. Cornea shape change was computed via finite element analysis, and the resulting change in cornea curvature was measured by fitting quadratic curves to the horizontal and vertical meridians of the cornea. Results suggest that these two sources of deforming force counteract each other and contribute to astigmatism in perpendicular directions.

Cyclosporin as an adjunct to glaucoma filtration surgery.

Purpose:Current adjunctive therapies to glaucoma surgery have unreliable effects, are toxic, and have numerous late complications associated with their use. This study examined whether topical cyclosporin (CsA) prolongs bleb survival after glaucoma filtration surgery. Methods:Anesthetized white New Zealand rabbits underwent glaucoma filtration surgery with a drainage tube. Cyclosporin (2%), applied intraoperatively or as topical treatment following glaucoma filtration surgery, was compared with intraoperative mitomycin C (MMC) and an untreated control group. Results:The bleb remained elevated for 15.1 ± 3.2 days in the untreated control group, 12.2 ± 2.1 days after intraoperative cyclosporin, and 27.5 ± 1.7 days after intraoperative mitomycin C (P< 0.001). When topical treatment with cyclosporin followed intraoperative mitomycin C, bleb survival significantly decreased to 19.2 ± 4.6 days (P= 0.003). Intraocular pressure (IOP) remained significantly reduced in the mitomycin C-treated group longer than in either the control or cyclosporine-treated groups. Conclusions:In comparison with mitomycin C, neither intraoperative nor postoperative treatment with cyclosporin was associated with a decrease in intraocular pressure or prolonged bleb survival. Contrary to the initial hypothesis, topical treatment with cyclosporin actually mitigated the beneficial effects of mitomycin C on bleb survival. Clinical implications of these findings for patients with functioning blebs deserve further study.

Time Course and Predictors of Amblyopia Improvement With 2 Hours of Daily Patching

For children with amblyopia secondary to strabismus and/or anisometropia, many clinicians initiate treatment with spectacles alone, if needed.2, 3 When amblyopic-eye improvement stops after a period with spectacles wear only, prescribing 2 hours of daily patching is often the next step.3, 4 Our purpose was to evaluate the amount and time course of amblyopia improvement with 2 hours of prescribed daily patching in children age 3 to <8 years, and to determine predictors of visual acuity (VA) improvement and amblyopia resolution.

The Birth of Ocular Pharmacology in the 20th Century

Nineteenth century ophthalmology, characterized by significant gains in diagnostic techniques, provided the basis for great advancements in treatment during the 20th century. Drug therapy at the turn of the century was empiric, palliative, and often toxic. The development of ocular pharmacology during the 20th century provided the basis for a rational therapeutic approach to ocular disease. Foremost among the therapeutic developments were antibiotics, due to their potential to cure conditions that frequently resulted in blindness. Second, other therapeutic classes provided palliative therapy for chronic diseases, and thus decreased morbidity. For example, drugs specifically targeting many different aspects of glaucoma have had remarkable success controlling intraocular pressure and forestalling development of blindness. In addition, other new approaches provided palliative therapy for nonblinding conditions and effective adjuncts to surgical procedures. Antiallergy and anti‐inflammatory drugs greatly increased patient comfort and facilitated treatment of allergic and inflammatory reactions. Local anesthetics and analgesia reduced patient discomfort during surgery. Other adjunct drugs improved surgical outcomes by reducing inflammation and infectious complications. The 21st century will undoubtedly provide novel approaches to address many of todays therapeutic dilemmas. Photodynamic therapy, growth factors, antisense technology, and genetic‐based therapies all show great promise. Many of the conditions that are only treated palliatively today will be curable in the next century using many of these pharmacological advances.

Cyclosporin-augmented laser peripheral iridoplasty.

BACKGROUND AND OBJECTIVE Almost all patients develop iritis following argon laser peripheral iridoplasty. Numerous adverse effects, particularly elevated intraocular pressure (IOP) and reduced microbial resistance, complicate therapy with topical corticosteroids. An immunomodulator, such as cyclosporin A (CsA), avoids these undesirable effects, yet may suppress ocular inflammation. MATERIALS AND METHODS Argon laser peripheral iridoplasty was performed on anesthetized rabbits with pigmented iris epithelium. Rabbits were randomly assigned to the untreated control, CsA (2%), or dexamethasone (0.1%) groups. Postoperative inflammation was documented by digital photography, IOP, and protein in aqueous humor. RESULTS Iris injection, aqueous flare, and fibrin decreased most rapidly in the control group, as did protein in aqueous humor. Decreases in IOP of 49% to 58% were similar in all three groups. There were no differences in conjunctival congestion between the CONCLUSION Neither treatment with antiinflammatory drugs that inhibit phagocytosis (e.g., topical steroids) nor treatment with anti-inflammatory drugs that suppress T-lymphocytes (e.g., topical sA) significantly attenuated inflammation following iridoplasty.

Acute Orbital Pseudotumor With Iatrogenic Intraorbital Air: A Diagnostic Dilemma

A 13-year-old black female was referred with unilateral granulomatous uveitis and orbital inflammation of sudden onset. Hematologic, serologic, bacteriologic, and ultrasonographic studies along with high resolution CT scans of the orbits were employed to determine the diagnosis and appropriate treatment. Subconjunctival corticosteroid injection containing air prior to referral obfuscated the ultimate diagnosis of pseudotumor. The Pediatric Infectious Disease service delayed definitive treatment with systemic steroids. Differential diagnosis of granulomatous uveitis with orbital inflammation are discussed. CT scan has significantly advanced the diagnosis and management of orbital pseudotumor.