Ultra-wide field imaging to assess the optic nerve and retina in Boston type I and II keratoprosthesis patients.

BACKGROUND: The ability to view the posterior segment in keratoprosthesis (Kpro) implanted patients is limited. The purpose of this retrospective, observational study was to investigate the use of ultra-wide field (UWF) scanning laser ophthalmoscopy imaging and its utility for serial evaluation of the retina and optic nerve in patients with either a Boston type I or II Kpro. METHODS: A retrospective chart review was performed for patients with a Boston type I or II Kpro seen at The Ohio State University Wexner Medical Center. Images were graded for quality by two masked observers on a defined four-point scale ("Poor", "Fair", "Good", or "Very good") and assessed for visible posterior segment anatomy. Interobserver agreement was described using the Kappa statistic coefficient (κ) with 95% confidence intervals. RESULTS: A total of 19 eyes from 17 patients were included in this study. Eighteen eyes had a type I Kpro, while one eye had a type II Kpro. UWF imaging from 41 patient visits were reviewed by two observers. Interobserver agreement between the two graders was fair for image quality (κ = 0.36), moderate for visibility of the macula with discernible details (κ = 0.59), moderate for visibility of the anterior retina with discernable details (κ = 0.60), and perfect agreement for visibility of the optic nerve with discernible details (κ = 1.0). In 6 eyes, UWF imaging was performed longitudinally (range 3-9 individual visits), allowing for long-term follow-up (range 3-46 months) of posterior segment clinical pathology. CONCLUSIONS: UWF imaging provides adequate and reliable visualization of the posterior segment in Kpro implanted patients. This imaging modality allowed for noninvasive longitudinal monitoring of retinal and optic nerve disease in this selected patient population.

Uveal Melanoma Mimicking Advanced Coats' Disease in a Young Patient.

BACKGROUND/AIMS: To report a case and the unique histopathology of a necrotic uveal melanoma mimicking advanced Coats' disease in a young adult. METHOD: A 26-year-old male presented with a blind, painful eye, total exudative retinal detachment, and bulbous aneurysms consistent with Coats' disease. No masses were visualized on ultrasound or CT scan, and the patient underwent enucleation of the eye. RESULTS: Histopathology of the involved eye confirmed a necrotic uveal melanoma with persistent spindle cells forming a collar around residual tumor vessels. CONCLUSION: Careful consideration is needed in approaching any patient with a blind, painful eye and opaque media, even in younger populations.

Histopathology of optic nerve pit-associated maculopathy.

PURPOSE: To describe the histopathologic findings of an eye bank specimen containing an optic nerve pit with associated serous elevation of the macula and cavernous atrophy of the optic nerve. METHODS: An eye bank specimen found to have an optic nerve pit with serous elevation of the macula was grossly examined and photographed. The globe was processed for both light and scanning electron microscopy. RESULTS: The scanning electron microscopic study of this eye with an optic nerve pit revealed holes in the diaphanous membrane overlying the nerve at the edge of the optic pit. Serial histopathology sections revealed a connection between the holes overlying the optic pit and the subretinal space via a schisis-like cavity in the retina. CONCLUSION: The discovery of an optic nerve pit with coexisting serous detachment of the macula in an eye bank eye and subsequent pathological evaluation provides support for current theories into the mechanism of the visual loss in this condition. Our finding supports syneretic vitreous to be the source of the subretinal fluid.

The contribution of heme propionate groups to the conformational dynamics associated with CO photodissociation from horse heart myoglobin.

Photoacoustic calorimetry and transient absorption spectroscopy were used to study conformational dynamics associated with CO photodissociation from horse heart myoglobin (Mb) reconstituted with either Fe protoporphyrin IX dimethylester (FePPDME), Fe octaethylporphyrin (FeOEP), or with native Fe protoporphyrin IX (FePPIX). The volume and enthalpy changes associated with the Fe-CO bond dissociation and formation of a transient deoxyMb intermediate for the reconstituted Mbs were found to be similar to those determined for native Mb (DeltaV1 = -2.5+/-0.6 ml mol(-1) and DeltaH1 = 8.1+/-3.0 kcal mol(-1)). The replacement of FePPIX by FeOEP significantly alters the conformational dynamics associated with CO release from protein. Ligand escape from FeOEP reconstituted Mb was determined to be roughly a factor of two faster (tau=330 ns) relative to native protein (tau=700 ns) and accompanying reaction volume and enthalpy changes were also found to be smaller (DeltaV2 = 5.4+/-2.5 ml mol(-1) and DeltaH2 = 0.7+/-2.2 kcal mol(-1)) than those for native Mb (DeltaV2 = 14.3+/-0.8 ml mol(-1) and DeltaH2 = 7.8+/-3.5 kcal mol(-1)). On the other hand, volume and enthalpy changes for CO release from FePPIX or FePPDME reconstituted Mb were nearly identical to those of the native protein. These results suggest that the hydrogen bonding network between heme propionate groups and nearby amino acid residues likely play an important role in regulating ligand diffusion through protein matrix. Disruption of this network leads to a partially open conformation of protein with less restricted ligand access to the heme binding pocket.