Reflective meniscometry: a non-invasive method to measure tear meniscus curvature

Abstract

Aims-To devise a method to measure tear meniscus curvature by a non-invasive specular technique. Methods-A photographic system was devised. The system consisted of a camera and an illuminated target with a series of black and white stripes oriented parallel to the axis of the lower tear meniscus. The target was mounted on a flash gun close to the objective of a Brown macrocamera and calibrated using a graduated series of glass capillaries of known diameter, ground down to expose the inner wall. It was then applied to normal human eyes (n=45) to measure the tear meniscus curvature. A video system was also assessed which provided qualitative online information about the tear meniscus. Conclusions-Reflective meniscometry is a non-invasive technique providing quantitative information about tear meniscus shape and volume and of potential value in the study of ocular surface disease. (Br J Ophthalmol 1999;83:92-97) Results-Using

Effect of non‐invasive tear stability assessment on tear meniscus height

“…Several methods are available to assess tear quantity, including slit-lamp evaluation with a graticule scale, optical pachymetry, video meniscometery and optical coherence tomography (OCT), which have all been used to quantify the tear meniscus (Mainstone et al 1996;Yokoi et al 1999;Doughty et al 2001;Johnson & Murphy 2005;Savini et al 2006;Wang et al 2006). Several non-invasive tear break-up time tests have been developed to evaluate tear film stability.…”

The increase of aqueous tear volume by diquafosol sodium in dry-eye patients with Sjögren’s syndrome: a pilot study

“…13 On the ocular surface of healthy subjects evaluated by meniscometry, an AT reportedly increased fluid volume for~2 min after instillation, and sodium hyaluronate increased the fluid volume for 5 min. 18 The fluid volume at 15 min after instillation of DQS was increased in the SS patients with dry eye and decreased lacrimal gland function. This longer mode of action may contribute to protect the ocular surface from the desiccation and ameliorate the epithelial damage.…”

“…8 Although the ΔTMR value is appropriate for evaluation of an increase in aqueous tear volume over time on the same ocular surface, it is impossible to compare the change in radius values of different eyes. 18 Nonetheless, it is very interesting that the increase in aqueous tear volume after instillation of DQS was similar in healthy subjects and SS patients with decreased lacrimal gland function. Moreover, the results of this present study showed that there was no significant correlation between the ΔTMR and Schirmer 1 test values, which reflect reflex tear secretion from the lacrimal glands, and no significant difference from those in the AT-treated eyes, even in patients with ocular irritation considered to be the trigger of reflex tear secretion.…”

“…6 Reflective meniscometry is a method used to optically measure the tear meniscus radius (TMR). [18][19][20][21] In a previous study, we measured the changes in TMR over time in normal human eyes after instillation of DQS using meniscometry, and reported that there was a significant increase in the fluid volume up until 30 min after the instillation. 8 In this pilot study, we used meniscometry to evaluate the changes in aqueous tear volume after instillation of DQS in patients for whom a definitive diagnosis of SS with dry eye (determined by a Schirmer 1 test value of o10 mm) had been provided, and compared the results with those obtained after instillation of an artificial tear (AT) solution.…”

Methods of Screening for Meibomian Gland Dysfunction

“…К ним относят: определение времени разрыва слез-ной пленки (ВРСП), определение симптоматического времени разрыва слезной пленки (СВРСП), компрес-сионную пробу, которая предполагает выдавливание секрета из устьев протоков мейбомиевых желез при их компрессии [5]. Кроме того, дефицит липидов, возник-ший как следствие ДМЖ, приводит к повышенному ис-парению водной фазы слезы, поэтому для определения тяжести процесса проводят тест Ширмера и биометрию слезного мениска [6,7].…”