What is indirect ophthalmoscopy?
The binocular indirect ophthalmoscope, or indirect ophthalmoscope, is an optical instrument worn on the examiner’s head, and sometimes attached to spectacles, that is used to inspect the fundus or back of the eye. It produces an stereoscopic image with between 2x and 5x magnification.
What is the difference between direct and indirect ophthalmoscopy?
Direct ophthalmoscopy one that produces an upright, or unreversed, image of approximately 15 times magnification. Indirect ophthalmoscopy one that produces an inverted, or reversed, image of 2 to 5 times magnification.
Why is it called indirect ophthalmoscopy?
Ophthalmoscopy is a routine exam done by ophthalmologists to examine the inside of the back of the eye, also known as the fundus or the posterior segment. The process is “indirect” because the fundus is viewed through a hand held condensing lens.
Why is indirect ophthalmoscopy preferred over direct ophthalmoscopy?
In comparing direct vs indirect ophthalmoscope, the indirect ophthalmoscope delivers a stronger source of light, greater opportunity for stereoscopic inspection of the eyeball interior, and a specifically designed objective lens.
How do you perform an indirect ophthalmoscopy?
Indirect Ophthalmoscopy 101
- Dilate properly. To conduct a good peripheral exam, the patient’s eyes must be well dilated.
- Position the patient for optimal viewing.
- Choose the right lens.
- Minimize lens distortion.
- Adjust the indirect headset.
- Depress the sclera.
- Ask for help when you need it.
What is the principle of indirect ophthalmoscope?
The principle of indirect ophthalmoscopy is to make the observer’s eye myopic by placing a strong convex lens in front of it. When both the illuminating and reflected beam pass through the pupil, that area of fundus is seen. 9. A pencil of rays can be traced from the patient’s fundus to the observer’s retina.
How do you practice indirect ophthalmoscopy?
Is Volk indirect ophthalmoscopy?
The volk lens is of paramount importance when carrying out a technique that is clinically known as slit lamp binocular indirect ophthalmoscopy (BIO). However, many of us simply refer to this procedure as ‘volk’ due to the popularity of these biomicroscopy lenses that are produced by Volk Optical.
What is laser indirect ophthalmoscopy?
Binocular laser indirect ophthalmoscopy (LIO), introduced in the early 1980s,1 is an essential tool for retinal specialists. For patients under general anesthesia, including pediatric or uncooperative patients, standard laser treatments using a slit lamp may be difficult and sometimes impossible.
Which is better indirect or direct ophthalmoscopy?
In indirect ophthalmoscopy, a real and inverted image is formed between the condensing lens and the observer. The advantage of stereopsis (depth perception) and a larger field of view makes indirect ophthalmoscope (IDO) more useful both in retina clinics and during posterior segment surgeries.
How does a binocular indirect ophthalmoscope work?
Binocular indirect ophthalmoscope. The light source mounted above and between the examiner’s eyes illuminates the condenser, which images the source at the periphery of the patient’s pupil. The illumination does not overlap the observation beam. The condenser lens is handheld; it forms an inverted aerial image of the retina.
Who was the first person to use indirect ophthalmoscopy?
This was followed by series of innovations and methods of examination including the indirect method of ophthalmoscopy developed by Reute in 1852 (Fig:1b), binocular model by Marc-Antoine Giraud-Teulon (Fig:1c) and more practical hand-held reflex-free binocular ophthalmoscope by Allvar Gullstrand (Fig:1d).
Can a slit lamp exam help with indirect ophthalmoscopy?
A slit-lamp exam with a 90-diopter (D) lens or an improved digital lens can help identify areas of concern, but it does not replace the dynamic interrogation of the retina with indirect ophthalmoscopy and scleral depression. 2. Position the patient for optimal viewing Successful indirect ophthalmoscopy depends on proper positioning.