Retinal blood flow in mild cognitive impairment and Alzheimer's disease.

Background: Patients with Alzheimer's disease (AD) demonstrate the narrowing of retinal veins and decreased retinal venous blood flow compared with control subjects. We assessed whether these abnormalities are present in patients with mild cognitive impairment (MCI).

Methods: After the determination of the global clinical dementia rating, 52 subjects (10 AD, 21 MCI, and 21 normal controls) underwent retinal hemodynamic profiling.

Defective Myogenic Response of Retinal Vessels Is Associated With Accelerated Onset of Retinopathy in Type 1 Diabetic Individuals.

Purpose: We seek to identify pathogenic mechanisms for diabetic retinopathy that can become therapeutic targets beyond hyperglycemia and hypertension. We investigated if a defective myogenic response of retinal arteries to increased perfusion pressure, which exposes capillaries to increased pressure and flow, is associated with the onset of clinical retinopathy.

Methods: We examined prospectively the incidence of retinopathy in type 1 diabetic individuals tested 4 years earlier for the retinal arterial myogenic response, and in a cross-sectional study the prevalence of defective myogenic response in type 1 patients who had diabetic retinopathy.

Effect of brimonidine on retinal vascular autoregulation and short-term visual function in normal tension glaucoma.

Purpose: To assess whether brimonidine 0.15% alters retinal vascular autoregulation and short-term visual function in normal tension glaucoma patients who demonstrate retinal vascular dysregulation.

Design: Nonrandomized clinical trial.

Effects of dorzolamide-timolol and brimonidine-timolol on retinal vascular autoregulation and ocular perfusion pressure in primary open angle glaucoma.

Purpose: To assess whether dorzolamide 2%-timolol 0.5% (D/T) and/or brimonidine 0.2%-timolol 0.

Multimodality animal rotation imaging system (Mars) for in vivo detection of intraperitoneal tumors.

PROBLEM Ovarian cancer stem cells (OCSCs) have been postulated as the potential source of recurrence and chemoresistance. Therefore identification of OvCSC and their complete removal is a pivotal stage for the treatment of ovarian cancer. The objective of the following study was to develop a new in vivo imaging model that allows for the detection and monitoring of OCSCs.

Effect of brimonidine on retinal blood flow autoregulation in primary open-angle glaucoma.

Purpose: To determine whether topically applied brimonidine affects the retinal hemodynamic autoregulatory response to posture change in patients with normal tension glaucoma.

Methods: Six patients with normal tension glaucoma (primary open-angle glaucoma and maximum untreated intraocular pressure <22 mmHg) in each eye were studied. We retrospectively reviewed retinal hemodynamic data acquired when the patients were off and on treatment with brimonidine 0.

Effect of aging on macular features of X-linked retinoschisis assessed with optical coherence tomography.

Purpose: X-linked retinoschisis (XLRS) is one of the most common causes of macular degeneration in young men. The purpose of this study was to use optical coherence tomography combined with ophthalmoscopy to study the effects of aging on the morphologic changes associated with XLRS.

Methods: Twenty-five eyes of 17 men with XLRS ranging in age from 3 years to 68 years were studied using ophthalmoscopy and optical coherence tomography.

Defective myogenic response to posture change in retinal vessels of well-controlled type 1 diabetic patients with no retinopathy.

Purpose: The current approach to the prevention of diabetic retinopathy relies on intensive anti-diabetes treatment and is only partially successful. A marker of retinopathy risk would enable strategies of surveillance, screening of adjunct drugs, and targeted drug interventions. The authors sought to identify early abnormalities of retinal vessels that are not prevented by the current therapeutic approach.

Analytical radiography for planar radiographic images implemented with a multi-modal system.

A radiographic system is optimized for the contrast inherent to small animals and is developed for a multi-modal imaging system devised for in-vivo studies. The range of X-ray energies utilized (generally considered "soft X-rays") enables enhanced spatial resolution and superior contrast for detailed study of the mouse anatomy and smaller specimens. Despite the difficulties presented by the complicated energy spectrum of soft X-rays, relevant system calibrations for bone measures are described in detail and applied to the mouse.

Ophthalmologic techniques to assess the severity of hyperviscosity syndrome and the effect of plasmapheresis in patients with Waldenström's macroglobulinemia.

Background: The aim of this study is to determine the serum immunoglobulin (Ig) M and serum viscosity (SV) levels at which retinal changes associated with hyperviscosity syndrome (HVS) as a result of Waldenström's macroglobulinemia (WM) occur. In addition, the effect of plasmapheresis on HVS-related retinopathy was tested.

Patients And Methods: A total of 46 patients with WM received indirect ophthalmoscopy, laser Doppler retinal blood flow measurements, serum IgM, and SV determinations.

Evaluation of macular abnormalities in Stargardt's disease using optical coherence tomography and scanning laser ophthalmoscope microperimetry.

Background: The purpose of this study is to evaluate the diagnostic value of optical coherence tomography (Stratus OCT) and scanning laser ophthalmoscope (SLO) microperimetry in patients with Stargardt's disease (STGD), and the correlation between macular morphology and visual function in these patients.

Methods: Twenty-two patients with STGD (mean age 44 years, range 11 to 71 years) and 20 age-matched healthy control subjects were included in the study. OCT imaging was performed using six radial line scans manually centered on the fovea.

Retinal blood flow and nerve fiber layer measurements in early-stage open-angle glaucoma.

Purpose: To evaluate the relationship between retinal circulatory abnormalities and retinal nerve fiber layer (RNFL) thinning in early-stage open-angle glaucoma (OAG) to help elucidate the mechanisms underlying the development of glaucomatous optic neuropathy.

Design: Prospective cross-sectional.

Methods: Twelve patients with early OAG and a known maximum untreated intraocular pressure less than 22 mm Hg (age, 61.

Effect of plasmapheresis on hyperviscosity-related retinopathy and retinal hemodynamics in patients with Waldenstrom's macroglobulinemia.

Purpose: Waldenström's macroglobulinemia (WM) is characterized by an overproduction of immunoglobulin M (IgM), which can lead to a hyperviscosity syndrome (HVS) and HVS-related retinopathy. Plasmapheresis is known to reduce serum viscosity (SV) and IgM levels. The purpose of this study was to investigate the effects of plasmapheresis on HVS-related retinopathy and retinal hemodynamic parameters in patients with WM.

Interferometric back focal plane microellipsometry.

We present a technique for ellipsometric analysis of materials with high lateral resolution. A Michelson-type phase-shifting interferometer measures the phase distribution in the back focal plane of a high numerical aperture objective. Local measurements of the ellipsometric parameter delta are performed over the entire spectrum of angles of incidence.

Retinal haemodynamics in individuals with well-controlled type 1 diabetes.

Aims/hypothesis: Abnormalities in retinal haemodynamics have been reported in patients with type 1 diabetes in advance of clinical retinopathy. These abnormalities could therefore be useful as early markers or surrogate endpoints for studying the microangiopathy. Since the DCCT, the increased focus on good glycaemic control is changing the natural history of diabetic retinopathy.

Retinal blood flow response to posture change in glaucoma patients compared with healthy subjects.

Purpose: To characterize the retinal vascular autoregulatory response to ocular perfusion pressure (OPP) changes in patients with glaucoma and in healthy control subjects.

Design: Observational cohort study.

Participants: Eighteen patients with open-angle glaucoma (OAG) and 8 control subjects, all females ages 40 to 60 years, were studied.

Retinal abnormalities in early Alzheimer's disease.

Purpose: There is evidence suggesting that visual disturbances in patients with Alzheimer's Disease (AD) are due to pathologic changes in the retina and optic nerve, as well as to higher cortical impairment. The purpose of this study was to evaluate retinal hemodynamic parameters and to characterize patterns of retinal nerve fiber layer (RNFL) loss in patients with early AD.

Methods: Nine patients with mild to moderate probable AD (mean Mini Mental State Examination score 24 of a possible 30 (age 74.

Laser Doppler instrumentation for the measurement of retinal blood flow: theory and practice.

The theory underlying the development of laser Doppler instrumentation for the measurement of retinal blood flow is framed in terms of (a) the enunciation of the Doppler principle; (b) the invention of the laser; and (c) the invention of the technique known as optical mixing spectroscopy. The features of the instrumentation, beginning with the first prototype in 1972 and culminating with the introduction of the Canon Laser Blood Flowmeter in 1998 are presented in detail. Results from seven separate studies reporting on the reproducibility of retinal blood flow measurements using the Canon instrument, as well as a review of 12 separate presentations made at the 2004 annual meeting of the Association for Research in Vision and Ophthalmology (ARVO) using the Canon instrument in studies involving retinal circulatory physiology and associated clinical research are also presented.

Hyperviscosity-related retinopathy in waldenstrom macroglobulinemia.

Objectives: To determine the earliest retinal changes associated with Waldenström macroglobulinemia (WM) and to ascertain the serum IgM and serum viscosity (SV) levels at which these changes occur.

Methods: Patients with WM were evaluated using indirect ophthalmoscopy with scleral depression, laser Doppler retinal blood flow measurements, and serum IgM and SV determinations. Hemodynamic findings were compared with those of a group of age-matched controls.

Retrobulbar haemodynamics in non-arteritic anterior ischaemic optic neuropathy.

Clinical evaluation of the optic nerve circulation in NAION remains an elusive goal yet to be fully achieved

Association between systemic arterial stiffness and age-related macular degeneration.

Background: A number of epidemiological studies suggest that age-related macular degeneration (AMD) and cardiovascular disease share the same risk factors. Systemic arterial stiffness is a clear indicator of cardiovascular disease. We investigated whether there is an association between directly measured systemic arterial stiffness and the presence of AMD.

Assessment of the effects of morphological changes related to age-related macular degeneration on optical coherence tomography retinal thickness measurements.

Background And Objective: Age-related macular degeneration (AMD) leads to morphological changes that can interfere with optical coherence tomography retinal thickness measurements. The effects of AMD on two available retinal thickness scan modes were tested.

Patients And Methods: Ninety-four scans, equally divided into Radial Line Scans (RLS) and Fast Macula Scans (FMS), of 42 patients with AMD were reviewed.