George J. Florakis

Confocal microscopy in Meretoja syndrome.

Purpose. To study the correlation between severity of clinical systemic symptoms and the degree of stromal haze and visibility of epithelial and stromal nerves on scanning slit confocal microscopy examination in Meretoja syndrome. Methods. Three patients with Meretoja syndrome were examined by slit-lamp microscopy and scanning slit confocal microscopy. Results. Increased symptoms and abnormal slit-lamp findings correlated positively with confocal microscopic stromal haze intensity and inversely with visibility of epithelial and stromal nerves on confocal examination. A prominent deposit, presumably amyloid, was observed contiguous to a stromal nerve of an affected cornea. In a severely affected cornea, no stromal or epithelial nerves were seen. Conclusion. The results of this study suggest that Meretoja syndrome causes corneal nerve damage and eventual degeneration that correlates with the degree of clinical involvement.

The Pathology of Posterior Amorphous Corneal Dystrophy

The youngest affected member of a family with a five-generation history of posterior amorphous corneal dystrophy underwent penetrating keratoplasty. The corneal button was studied by light and electron microscopy, representing the first pathologic description of this condition. Light microscopy demonstrated fracturing of the most posterior collagen layers of the stroma and focal attenuation of endothelial cells. Electron microscopy showed the collagen fibers in the most posterior stromal lamellae to be disorganized. Descemets layer was interrupted by a band of collagen fibers resembling stroma, and there was loss of endothelial cells. These findings suggest a developmental abnormality in the formation of the posterior stroma and Descemets membrane in posterior amorphous corneal dystrophy.

Penetrating keratoplasty in active Acanthamoeba keratitis.

Purpose: To report the results of penetrating keratoplasty (PK) in active Acanthamoeba keratitis (AK). Methods: Nine patients with deep stromal infiltrates because of AK were treated with intensive antiamoebic medical therapy followed by PK during the acute infectious phase because of poor clinical response or poor compliance. Antiamoebic therapy was tapered after PK. Results: Visual acuity ranged from 20/15 to 20/50 after an average of 17 months after PK with no signs of recurrences. Patients had rapid resolution of symptoms. Conclusion: PK is a viable option for active AK not responding to maximum medical treatment.

Corneal graft survival and intraocular pressure control in coexisting penetrating keratoplasty and pars plana Ahmed Glaucoma Valves.

Purpose To evaluate corneal graft survival and intraocular pressure (IOP) control after penetrating keratoplasty (PK) and pars plana Ahmed Glaucoma Valve (AGV) implantation among patients with coexisting glaucoma and corneal disease. Methods Retrospective chart review at an institution of 25 eyes (24 patients) that received PK and pars plana AGV. Results The mean postoperative follow-up was 23 months (range, 2–106 months). Survival of the grafts was 89% (16 of 18 eyes) at 1 year and 63% (5 of 8) at 2 years. IOP control was 78% (15 of 19) at 1 year and 44% (4 of 9) at 2 years. By Kaplan–Meier analysis, the 50% probability of sustained graft clarity occurred at 28 months and that of sustained IOP control at 24 months. By last follow-up, best-corrected visual acuity had improved by at least 1 line in 52% (13 of 25) of eyes compared with preoperative values. Preoperative factors, including peripheral anterior synechiae, were not found to be associated with graft survival, IOP control, or visual acuity at 1 year. Conclusion Pars plana AGV can successfully control IOP in PK patients in the short and intermediate terms, but graft clarity and IOP control diminish over time. Graft decompensation, when it did occur, likely reflects the associated ocular morbidity and clinical complexity of this circumscribed cohort of eyes.

Night Vision Testing in Unoperated Eyes

BACKGROUND We previously described a simple test which evaluates image degradation in post-excimer laser (PRK) patients under scotopic conditions. After refractive surgery, corneal haze, ablation zone decentration, ablation zone/pupillary diameter disparity, and under-correction each result in a characteristic pattern on the Night Vision Recording Chart. METHODS Using the same method, further studies evaluated night vision image degradation in 118 un-operated emmetropic, myopic, hyperopic, and astigmatic eyes and in 26 contact lens wearers. RESULTS Scotopic image degradation increases with myopic refractive error, image displacement increases with astigmatism, and contact lens wearers have more image degradation that with spectacle correction. CONCLUSION Our Night Vision Recording Chart offers a simple, reproducible method to characterize image degradation under scotopic conditions.

Evaluation of Night Vision Disturbances

BACKGROUND Evaluation of night vision disturbances has relied on subjective responses. We designed a test to more objectively measure night vision disturbances. METHODS The test consisted of projecting a small circle onto a visual acuity screen. The patient is asked to draw exactly what he sees on an Amsler grid. We evaluated 118 eyes in photopic and scotopic conditions and under different conditions of refractive correction. RESULTS Image degradation increased in scotopic conditions for myopes (p = .0001), hyperopes (p = .005), and emmetropes (p = .01). Myopic refractive error correlated with size of glare response (p = .001). Astigmatism correlated with decentration of glare response (p = .0001). Decentration increased in scotopic compared to photopic conditions (p = .002). CONCLUSION Our test offers a simple, convenient way to evaluate night vision disturbances and may offer a means of assessing night vision disturbances in patients considering refractive surgery.

Posterior Amorphous Corneal Dystrophy Associated With Keratoglobus: A Case Report

Purpose: Posterior amorphous corneal dystrophy (PACD) is a rare disorder characterized by sheet-like opacification of the posterior corneal stroma, corneal thinning, and decreased corneal curvature. It is not known to be associated with progressive corneal ectasia. In this report, we examine the course of a patient with PACD who developed bilateral keratoglobus-type corneal ectasia. Methods: The clinical history of a single patient is reviewed from birth through age 15. Visual acuity, refraction, ultrasound pachymetry, anterior segment optical coherence tomography, corneal topography, and corneal tomography are presented. Results: The patient was noted to have bilateral cloudy corneas at birth. Congenital infection, metabolic disease, and glaucoma were ruled out. Anterior segment optical coherence tomography demonstrated posterior stromal opacification typical of PACD. Over time, the patient progressed from best uncorrected visual acuity of 20/20-2 OD and 20/25-3 OS to PROSE lens-corrected visual acuity of 20/30-3 OD and 20/30-3 OS. Central corneal thinness progressed from 491 to 408 &mgr;m in the right eye and from 505 to 389 &mgr;m in the left eye. Steepening in corneal axial/sagittal curvature developed in both eyes beginning inferiorly then involving the corneas diffusely. Conclusions: In this case report, we illustrate progressive corneal ectasia in a patient with PACD. Although both conditions may represent changes in the structure and integrity of corneal collagen, whether an association exists between the 2 conditions is unknown.

Ocular Manifestations of Inherited Phospholipase-Cγ2-Associated Antibody Deficiency and Immune Dysregulation.

Purpose: To report the ocular manifestations of phospholipase-C&ggr;2–associated antibody deficiency and immune dysregulation (PLAID). Methods: Case report and literature review. Results: A 21-year-old woman diagnosed with PLAID was referred for evaluation of repeated episodes of ocular inflammation resulting in bilateral peripheral corneal pannus with episcleritis and corneal scarring accompanied by systemic manifestations including epidermolysis bullosa and interstitial lung disease. Systemic immunosuppression with corticosteroids and interleukin-1 (IL-1) receptor antagonist (anakinra) was supplemented with topical anakinra to avoid systemic side effects, which resulted in partial improvement of the ocular symptoms. Oral prednisone was restarted to treat active lesions during bouts of inflammation. Conclusions: Ocular PLAID is a bilateral chronic or recurrent inflammatory disease of the ocular surface leading to severe and early cicatricial ocular surface and corneal involvement because of high IL-1 production. Management of PLAID may require both topical and systemic immunomodulatory treatments, potentially including targeted local anti–IL-1 therapy.

A New Scleral Suction Trephine for Retrieval of Corneoscleral Donor Tissue

BACKGROUND Removal of donor corneo-scleral shell from a cadaver, leaving the remainder of the eye in place, has become a popular technique. Manual removal can result in excessive trauma to the corneal endothelium or an uneven scleral rim. METHODS We describe a new technique for corneal retrieval using a sceral suction trephine. RESULTS The scleral suction trephine was cut evenly in our eyebank study. There was no additional trauma to the endothelium and the scleral rim was regular. CONCLUSION Suction trephination of the sclera in retrieval of corneal donor tissue appears to be safe and effective.

Iowa PK Press for donor corneas--a comparative study of donor corneal shape.

BACKGROUND A new cornea press for cutting donor corneal buttons from the endothelial side, the Iowa PK Press, is described. Major modifications of the Bourne Press include a spring-activated piston without lateral sway, a centering device for a Teflon cutting pad, and the ability to accommodate a wider range of trephine sizes (6.2 mm to 10.0 mm). METHODS The Iowa PK Press was compared with the Bourne Corneal Press and trephination by hand in a series of 15 donor cornea trephinations. Measurements taken from photographs of the buttons included endothelial diameter, epithelial diameter, and edge angles. RESULTS The Iowa PK press cut buttons that had a slightly larger epithelial and endothelial diameter when compared to hand trephination (p < .05, analysis of variance) with less undercutting of the endothelial surface. There was no statistically significant difference in epithelial and endothelial diameters, eccentricity, or edge angles between the two presses. CONCLUSIONS The Iowa PK Press is more versatile than the Bourne Press in terms of the potential range of diameter of corneal buttons that can be created.