This study examines the connection between glaucoma and the optic disc, cup, and neuroretinal rim size. The use of a slit-lamp and funduscopy lens as a technique for determining and estimating the optic disc size is particularly emphasized. Through this study, a clinical manual for working clinicians will be developed by summarizing this information and making it easily accessible for in-office use. PubMed, Science Direct, Ovid, Medline journals, and inter-library journals were used to find papers and abstracts of relevant studies for this review. The most common search terms were: procedures for assessing optic disc size, variance in optic disc size between populations, and ophthalmoscopic methods for measuring optic discs. The search period spanned 2020 to 2022. The following criteria were used to determine whether an article should be included or excluded: a critical evaluation of the various methods used to measure the optic disc, the significance of including population-specific variations in the size of the optic disc, and justifications for the relative risk of glaucoma associated with the size of both the optic disc and the optic cup. According to numerous studies, a slit lamp and funduscopy lens can be used to estimate the size of the optic disc. Additionally, this review discovered a weak association between measures taken at a slit lamp and those taken with more exact office tools, including fundus photography. Using fundoscopic technologies is an effective and affordable method for measuring the optic nerve head while retaining a high level of accuracy. These dimensions can be used to divide the sizes of optic discs into three groups: small, average, and large.