Standardized Three-Dimensional Lateral Distraction Test: Its Reliability to Assess Medial Canthal Tendon Laxity

Abstract

Background Assessment of MCT laxity is critical to the surgery options. Our study aimed to analyze the reliability of measuring medial canthal tendon (MCT) laxity by using a novel standardized three-dimensional lateral distraction test (3D-LDT). Methods Forty-eight Caucasian volunteers (25 males and 23 females, 96 eyes) between 22 and 84 years of age (55.6 ± 18.6 years old) were included in our study. From a neutral position, the lower eyelid was gently pulled laterally along a horizontal line to define the most distracted position of the lower punctum. Both in the neutral and distracted position, standardized 3D images were acquired for each subject by two observers, and each image were measured twice by two raters. Four landmarks and six corresponding linear measurements were evaluated for intra-rater, inter-rater, and inter-method reliability. Results Intra-rater, inter-rater and inter-method reliability analyses of 3D-LDT revealed an intraclass correlation of more than 95%, a mean absolute difference of less than 1 mm, and a technical error of measurement of less than 1 mm. Measurements of relative error (2.59–12.04%) and relative technical error (1.83–16.05%) for the inter-landmarks distance from pupil center to the lower punctum were higher than those from limbus nasal center to the lower punctum (6.13–30.39 and 4.34–26.85%, respectively). Conclusions This study provided high reliability of the three-dimensional lateral distraction test (3D-LDT) for assessing medial canthal tendon (MCT) laxity, which were never evaluated by digital imaging system. Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Grand Challenges and Opportunities in Surgical Ophthalmology: Together for a Shared Future

“…A number of recent papers have used AI for eyelid and periorbital measurements (91,92). A similar approach could be used to classify periorbital lesions with 3D stereophotogrammetry and apply AI analysis to aid in diagnosis and triage (93)(94)(95)(96)(97)(98).…”

Validation of the Portable Next-Generation VECTRA H2 3D Imaging System for Periocular Anthropometry

“…Most of the existing 3D photogrammetry systems are static devices, which prominently feature in capturing photos of participants from three different angles at a single time point and composing a 3D photo using a computer. Previous studies have proposed the first standardized periocular anthropometric protocol ( 17 , 18 ) and showed potential clinical applications, including a novel standardized lower eyelid tension distraction test and a lateral distraction test ( 19 , 20 ). The reliability (repeatability) and accuracy of the VECTRA M3 static device is very high for linear, curvilinear, angular, area, and volume measurements ( 21 – 25 ).…”

A modified 3D stereophotogrammetry-based distraction test for assessing lower eyelid tension

“…With the dramatic development of high-resolution threedimensional (3D) stereophotogrammetry, the digital system has been utilized in the measurement of the normal anthropometric parameters of the cranial, facial, and periocular regions and in the planning of the optimal procedure for reconstructive eyelid surgeries [14][15] . However, only a few studies have investigated the application of 3D imaging systems in functional eyelid tests [16][17] . A digital imaging system was first utilized in a study by Stuchi et al [18] to investigate the reliability of using the DT to assess LET.…”