William H Morgan

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PURPOSE To quantify the distribution and morphometric characteristics of capillary networks in the human perifovea. To determine correlations between the location of neuronal subcellular compartments and the morphometric features of regional capillary networks in the layered retina. METHODS The perifoveal region, located 2 mm nasal to the fovea, was(More)
PURPOSE To determine whether changes in central retinal vein pulsation characteristics occur in glaucoma, and how these are related to indices of glaucoma severity. DESIGN A large, consecutive, prospective, case-controlled study. PARTICIPANTS Ninety-four consecutive glaucoma patients and 105 glaucoma suspects seen in a tertiary referral clinic were(More)
PURPOSE To study the time-dependent effects of elevated intraocular pressure (IOP) on axonal transport and cytoskeleton proteins in the porcine optic nerve head. METHODS Fifteen pigs were used for this study. Rhodamine-beta-isothiocyanate was injected into the vitreous of each eye to study axonal transport. IOP in the left eye was elevated to 40 to 45 mm(More)
PURPOSE To investigate the axonal cytoskeleton changes occurring in the prelaminar region, lamina cribrosa, and postlaminar region of the porcine optic nerve after an acute increase in intraocular pressure (IOP) and whether this corresponds with axonal transport abnormalities. METHODS Six white Landrace pigs were used. The left eye IOP was elevated to 40(More)
Retinal ganglion cells (RGCs) are specialized projection neurons that relay an immense amount of visual information from the retina to the brain. RGC signal inputs are collected by dendrites and output is distributed from the cell body via very thin (0.5-1 μm) and long (∼50 mm) axons. The RGC cell body is larger than other retinal neurons, but is still only(More)
It is generally accepted that glaucoma occurs when intraocular pressure (IOP) is raised above atmospheric pressure beyond tolerable limits for the optic disc. However, the other, unseen side of the optic disc is not air but a set of pressure compartments dominated by the cerebrospinal fluid (CSF) within the subarachnoid space. This invisibility has made(More)
BACKGROUND The aim of the present study was to assess the relative effectiveness of tube surgery and cyclodiode laser in terms of achieving intraocular pressure control. METHODS A retrospective study was undertaken to compare patients undergoing double plate Molteno tube implantation with patients undergoing diode cyclophotocoagulation. Intraocular(More)
PURPOSE To measure the effects of cerebrospinal fluid pressure (CSFp) on retrolaminar tissue pressure (RLTp) and the translaminar pressure gradient (TLPG), particularly at low CSFp, which is the normal situation in erect posture. METHODS Micropipettes coupled to a servonull pressure system were passed into eyes of anesthetized dogs to the optic disc and(More)
AIM Retinal vein ophthalmodynamometric force (ODF) is predictive of future optic disc excavation in glaucoma, but it is not known if variation in ODF affects prognosis. We aimed to assess whether a change in ODF provides additional prognostic information. METHODS 135 eyes of 75 patients with glaucoma or being glaucoma suspects had intraocular pressure(More)
Oligodendrocyte-derived myelin retards the ability of CNS axons to regenerate following transection. The intrinsic response of CNS axons to an axotomy insult may be vastly different in the absence of myelin. However, the paucity of adequate experimental models has limited detailed investigation of cellular behaviour following axon transection in an(More)