No abstract

ABSTRACT.Purpose: To examine the definition, evaluation methodology, association to ocular blood flow and potential clinical value of contrast sensitivity (CS) testing in clinical and research settings, focusing in patients with ischemic retinal disease. Methods: A review of the medical literature focusing on CS and ocular blood flow in ischemic retinal disease. Results: CS may be more sensitive than other methods at detecting subtle defects or improvements in primarily central retinal ganglion cell function early on in a disease process. CS testing attempts to provide spatial detection differences which are not directly assessed with standard visual acuity chart testing. Analyzing all studies that have assessed both CS change and ocular blood flow, it is apparent that both choroidal circulation and retinal circulation may have an important role in influencing CS. Conclusion: The concept that CS is directly influenced by ocular blood flow is supported by reviewing the studies involving both. Although the studies in the literature have not established a direct cause and effect relationship per se, the literature review makes it logical to assume that changes in retinal and choroidal blood flow influence CS. This raises the possibility that a subjective visual characteristic, specifically CS, may be able to be evaluated more objectively by studying blood flow. It appears appropriate to study the relationship between blood flow and CS more extensively to develop improved ways of measuring various aspects of blood flow to the eye and to best quantify early changes in visual function.

Colour Doppler imaging (CDI) is a frequently cited methodology for quantifying ocular blood flow velocities. This investigation reviews the feasibility of creating a normative database of CDI parameters in glaucoma patients and controls. A literature search was conducted for CDI studies involving glaucomatous eyes. Using data from these studies, a weighted mean was derived for the peak systolic velocity, end diastolic velocity and Pourcelot's resistive index in the ophthalmic, central retinal and posterior ciliary arteries. A multivariate analysis was performed to identify whether methodological characteristics contributed to the inter-study variance in CDI values. Data from 3061 glaucoma patients and 1072 controls were included. The mean values for glaucomatous eyes were within one standard deviation of the values for controls for most CDI parameters. Gender mix (p=0.043), intraocular pressure status (p=0.017), frequency of the ultrasound transducer (p=0.02) and whether the patients were on antihypertensive therapy (p=0.004) contributed to the variance. Methodological differences create inter-study variance in CDI values, complicating the construction of a normative database and limiting its utility. Because the mean values for glaucomatous and normal eyes have overlapping ranges, caution should be used when classifying glaucoma status based on a single CDI measurement.

Introduction: To examine the comparative

Patient: Female, 60Final Diagnosis: Necrotizing fasciitis of the eyeSymptoms: Eye painMedication: —Clinical Procedure: —Specialty: Infectious DiseasesObjective:Unusual clinical courseBackground:Necrotizing fasciitis (NF) of the orbit is a rare and deadly condition that requires prompt surgical and medical management to decrease morbidity and mortality.Case Report:Here we present an interesting case of an individual who developed fulminant NF of the left orbit requiring emergent surgical intervention, antibiotics, and subsequent hyperbaric oxygen therapy in an attempt to save the eye.Conclusions:With an early and aggressive multifaceted approach using antibiotics, surgery, and hyperbaric oxygen it may be possible to preserve eye structure and function. Without treatment NF is a rapidly progressive condition and can result in significant morbidity.