{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,23]],"date-time":"2026-08-23T15:10:10Z","timestamp":1787497810480,"version":"build-2736575974"},"reference-count":32,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"3","license":[{"start":{"date-parts":[[2024,12,27]],"date-time":"2024-12-27T00:00:00Z","timestamp":1735257600000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,3]]},"abstract":"<jats:p>The pupillary direct and consensual reflex is an important non-invasive quick assessment of the neurological state of the eye. Currently, there is no cheap and affordable recording tool for screening and documentation of a relative afferent pupillary defect. We describe how to construct a frugal, do-it-yourself handheld scotopic binocular pupillometer device called Pupilmate. Two simple Wi-Fi-enabled board cameras fitted on both sides of the back of a rectangular cardboard box separated by a central paper divider, one side of the rectangular box was left open. An infrared red (IR) light source in the form of light-emitting diodes (LEDs) was fitted around each of the cameras. Two white light LEDs were fitted on either side of the box controlled by a two-way switch. A simultaneous video stream of both pupils could then be tuned in on any chosen device using the internet. Each pupil is manually illuminated for a desired time allowing recording of direct as well as consensual reflexes, which are objectively observed. Pupil reaction was easily recorded and repeatable using Pupilmate. It served as a good medium for initial screening in an outpatient department (OPD) setting, outreach programs, clinics, etc.<\/jats:p>","DOI":"10.4103\/ijo.ijo_859_24","type":"journal-article","created":{"date-parts":[[2024,12,27]],"date-time":"2024-12-27T10:00:32Z","timestamp":1735293632000},"page":"437-441","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":1,"title":["Pupilmate: A do-it-yourself frugal pupilometer"],"prefix":"10.4103","volume":"73","author":[{"given":"Ruhel K","family":"Chacko","sequence":"first","affiliation":[{"name":"Department of General Ophthalmology, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Coimbatore, Tamil Nadu, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prithvi","family":"Chandrakanth","sequence":"additional","affiliation":[{"name":"Department of Vitreoretinal Services, Dr. Chandrakanth Nethralaya, Kozhikode, Kerala, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aniket","family":"Roy","sequence":"additional","affiliation":[{"name":"Vellore Institute of Technology, School of Electronics Engineering (SENSE), Hyderabad, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hirika","family":"Gosalia","sequence":"additional","affiliation":[{"name":"Department of Cornea and Refractive Surgery, LVPEI Institute, Hyderabad, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gargi","family":"Aggarwal","sequence":"additional","affiliation":[{"name":"Vellore Institute of Technology, School of Civil Engineering (SCE), Hyderabad, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V","family":"Narendran","sequence":"additional","affiliation":[{"name":"Department of Retina and Vitreous Services, Aravind Eye Hospital and Post Graduate Institute of Ophthalmology, Coimbatore, Tamil Nadu, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2024,12,27]]},"reference":[{"key":"R1-20260422","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1186\/s13054-016-1239-z","article-title":"Reliability of standard pupillometry practice in neurocritical care: An observational, double-blinded study","volume":"20","author":"Couret","year":"2016","journal-title":"Crit Care"},{"key":"R2-20260422","first-page":"41","article-title":"Infrared pupillometry. 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