The slider is attached to a square section metal rule. The RNPR consists of a rotating four-sided cubical drum held on a slider. (A) a reduced Snellen chart (B) section of the General Post Office (G.P.O) telephone directory (C) Times Roman typeface (D) a dot on a line. The design of RNPR Target drums ( Figure 1)įigure 1 Targets used in RAF near point rule (RNPR). The RNPR is marketed by Haag-Streit ® as RAF binocular gauge. Apart from the UK and Ireland, it is popular in Asia, including Bhutan, India, and Nepal. After the introduction, its use has widely expanded and continues as a preferred ophthalmic tool. The instrument was used to assess the visual functions like convergence and accommodation as well as to establish the correlation between distance and near visual acuity ( 12). It stated that the RNPR was originally developed in the United Kingdom (UK) in the mid-1950s to assess the visual abilities of the individuals conscripted into the US military to carry out routine clerical responsibilities. The RNPR was first mentioned in the literature by J. Considering the clinical significance of measuring NPC, understanding the design, procedure, merits and demerits of RNPR can help us in properly measuring the NPC. Most of the optometrists, however, consider NPC as the main factor in making a diagnosis of convergence insufficiency ( 11). The Convergence Insufficiency Treatment Trial (CITT) group included a receded NPC of 6 cm or more as an important criterion for diagnosis of convergence insufficiency along with an exophoria at near greater than distance by at least 4 prism diopters, and a decreased positive fusional vergence (PFV) at near ( 10). Convergence insufficiency, affecting about 5% of the global population, may have a negative impact on the health-related quality of life, potentially causing difficulties with reading and associated near work ( 8, 9). Convergence insufficiency is a non-strabismic binocular disorder and a common cause of asthenopic symptoms ( 7). It is also used as a standard tool for research purpose and to provide therapeutic home-based orthoptic exercises ( 1, 2).The assessment of NPC is an important part of a routine eye examination as it serves as the primary assessment for the diagnosis and management of convergence insufficiency ( 3- 6). RAF near point rule (RNPR) also known as Royal Air Force (RAF) rule is a routinely employed instrument in ophthalmology and optometry practices to measure near point of convergence (NPC) and near point of accommodation (NPA). Received: 22 November 2016 Accepted: 08 February 2017 Published: 15 March 2017. Keywords: Convergence insufficiency near point of convergence (NPC) RAF near point rule (RNPR) Policy of Dealing with Allegations of Research Misconduct.Policy of Screening for Plagiarism Process.
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