Ophthalmoscopy, also called funduscopy, is a test that allows a health professional to see inside the fundus of the eye and other structures using an ophthalmoscope (or funduscope). It is done as part of an eye examination and may be done as part of a routine physical examination. It is crucial in determining the health of the retina, optic disc, and vitreous humor. The pupil is a hole through which the eye's interior will be viewed. Opening the pupil wider (dilating it) is a simple and effective way to better see the structures behind it. Therefore, dilation of the pupil (mydriasis) is often accomplished with medicated eye drops before funduscopy. However, although dilated fundus examination is ideal, undilated examination is more convenient and is also helpful (albeit not as comprehensive), and it is the most common type in primary care. An alternative or complement to ophthalmoscopy is to perform a fundus photography, where the image can be analysed later by a professional. Types It is of two major types: 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. Each type of ophthalmoscopy has a special type of ophthalmoscope: The direct ophthalmoscope is an instrument about the size of a small flashlight (torch) with several lenses that can magnify up to about 15 times. This type of ophthalmoscope is most commonly used during a routine physical examination. The pan-ophthalmoscope has a larger primary lens with a variable focusing, allowing for a wider field-of-view. An indirect ophthalmoscope, on the other hand, constitutes a light attached to a headband, in addition to a small handheld lens. It provides a wider view of the inside of the eye. Furthermore, it allows a better view of the fundus of the eye, even if the lens is clouded by cataracts. An indirect ophthalmoscope can be either monocular or binocular. It is used for peripheral viewing of the retina. Medical uses Ophthalmoscopy is done as part of a routine physical or complete eye examination, mainly done by optometrists and ophthalmologists. It is used to detect and evaluate symptoms of various retinal vascular diseases or eye diseases such as glaucoma. In patients with headaches, the finding of swollen optic discs, or papilledema, on ophthalmoscopy is a key sign, as this indicates raised intracranial pressure (which could