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Neurologic Diagnosis
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
This novel handheld direct ophthalmoscope (Figure 1.18) gives a larger view of the fundus (25 vs. 5 degrees) and more magnification. Because of the patient eyecup, it is easier to see through small pupils. It is more expensive than the conventional ophthalmoscope, but some neurologists/physicians now use it exclusively.
Pathological Processes of the Eye Related to Chemical Exposure
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
The most common method of indirect ophthalmoscopy requires the use of a light source mounted on a headband (Figures 2 and 3), a binocular indirect ophthalmoscope and a hand-held condensing lens. The examiner stands about 2 to 3 ft from the animal and the light is directed through the dilated pupil. The hand-held condensing lens is then placed between the observer’s light source and the animal’s eye and is slowly moved toward the observer until the retinal image is clear and seems to fill the entire lens. Then, by gently moving the lens and the light source (keeping them in the same plane), all quadrants of the retina may be visualized. A small pupil indirect ophthalmoscope is also available for those relatively rare instances in which a fundus examination must be performed and the pupil cannot be dilated.1
Introduction
Published in Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza, Computer-Aided Glaucoma Diagnosis System, 2020
Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza
Ophthalmoscopy is a device used to examine the inside part of the eye and can be performed on a dilated or non-dilated eye. The color, shape, and overall health of the optic nerve are important signs in glaucoma diagnosis that can be checked directly or by using a digital camera to photograph the optic nerve.
A Review to Populate A Proposed Cost-Effectiveness Analysis of Glaucoma Screening in Sub-Saharan Africa
Published in Ophthalmic Epidemiology, 2022
Olusola Olawoye, Augusto Azuara-Blanco, Ving Fai Chan, Prabhath Piyasena, Grainne E. Crealey, Ciaran O’Neill, Nathan Congdon
Ophthalmoscopy (Direct): Direct ophthalmoscope is often used to examine the optic nerve head with or without dilation of the pupil. An advantage of the direct ophthalmoscope is its portability and use of batteries instead of electrical current, access to which may be problematic in remote areas. The main disadvantage, however, is its inability to give a stereoscopic view of the nerve. Harper et al.68 reported a sensitivity of 81% (95% CI 69–89%) and a specificity of 90% (95% CI 84–95%) with the use of the instrument, when compared to a gold standard of stereophotography in the evaluation of the narrowest rim width for glaucoma screening.68 Cook et al.69 reported that the use of the direct ophthalmoscope using a cut-off of 0.7 for the vertical cup to disc ratio, in addition to the testing for afferent pupil defect, could give an accuracy of up to 90% for the case detection of glaucoma.
The utility of a direct ophthalmoscope in estimating the magnitude of refractive error using a modification of the Brückner test
Published in Expert Review of Ophthalmology, 2021
Praveena S. Kumar, Yogish Subraya Kamath
Refractive errors are the second major cause of blindness in India [1]. Refractive errors in children are often missed due to challenges in evaluation, and may result in amblyopia if left untreated. Poor vision also hinders academic performance and the child’s over all development [2]. These events can be prevented by the early detection of advanced refractive errors, which can ensure timely management with spectacles. Various devices like automated refractometers and photo screeners have been developed for detection of refractive errors, but are not in widespread use as they are expensive and inaccessible in rural areas [3,4]. Simpler techniques like retinoscopy are time consuming and require personnel trained in Ophthalmology [3]. The direct ophthalmoscope is an instrument that is frequently used by Pediatricians and Internists, for viewing the ocular fundus. The utility of this device in estimation of the refractive error would help in early detection and referral of individuals with higher refractive errors.
The ocular health and visual function status of sewing professionals of garment factories of Kathmandu Valley
Published in Cogent Medicine, 2021
Sadhana Sharma, Ranju Kharel Sitaula, Sanjeeb Mishra, Gulshan Bdr Shrestha, Anand Kumar Sharma
Participants underwent detailed ocular examination; an anterior and posterior segment eye examination was carried out with a portable slit lamp and direct ophthalmoscope. Schirmer test using Whatman-41 filter paper was used to assess dry eyes; wetting of the Schirmer strip (equal to or greater than 10 mm in 5 min) was considered normal. Presenting distance and near visual acuity was assessed with a Log MAR chart at a distance of three meters and findings were recorded. Amblyopia was diagnosed when vision was 0.3 Log MAR or worse in one or both eyes after a careful eye examination including funduscopy and cycloplegic refraction. Static retinoscopy was carried out at a distance of 50 cm with the help of a retinoscope followed by subjective refraction providing optimum visual acuity. Emmetropia was considered as spherical equivalent