The Montreal Experience: A Retrospective Study Part I—Basic Principles and Treatment Algorithm

Abstract

CONTEXT: Authors have refined myopia control strategies (MCS) from their experience treating more than 800 children who were followed at the Montreal School of Optometry Clinic (CUV). They developed a treatment algorithm known as the Montreal Experience (ME). Contrary to many other MCS, treatment modalities are selected after careful evaluation of a patient’s parameters (rate of progression, age of myopia onset, corneal parameters, pupil area), the risk factors for ocular pathology (growth charts), and taking into account the patient’s lifestyle and potential compliance. This represents a customized approach for each patient. PURPOSE: To evaluate the efficacy of MCS used following ME algorithm; the primary outcome relates to axial length progression over 24 months. METHODS: This is a retrospective study, conducted after approval of University IRB. Data were extracted from the file of each patient who: (1) consulted CUV between January 2017 and December 2018 and (2) were kept under the same MCS (same design/concentration). Clinical population is composed of 298 patients (35% Caucasian; 45% Asian; 20% others), with a median age of 11 (range 5–18). The treatment options were orthokeratology (OK-4 designs; N = 140), multifocal soft contact lenses (SMCL; 5 designs; N = 128), and low-dose atropine (LDA 0.01% to 0.25%; N = 42). RESULTS: Results are analyzed through sophisticated statistical models, designed for this purpose. At the end of a stepwise selection process that sequentially removed model terms that were not statistically significant, nine model terms remained: month, modality, the interaction of month and modality, refraction (SEQ), the interaction of SEQ and modality, gender, age, the interaction of age and month, and the interaction of age and modality. A total of 298 files were kept for analysis. Participant age varied from 9.7 to 12.5 years old. Baseline AL varied from 24.9 to 25.3 mm and SE refraction was −3.7 + 1.7 D on average. This study population was divided between Caucasian (34%), Asian (44%), and other ethnic origins (22%). Overall results indicate that results vary according to modality and months only. There is no statistical difference based on age, gender, and SEQ. All methods used were effective to slow the natural AL growth. Evolution was the lowest when using smaller treatment zones OK lenses (0.249 mm) and the highest (0.376 mm) for those treated with LDA. This OK advantage was statistically significant versus other modalities at 1 and 2 years. CONCLUSION: The Montreal Experience reveals that personalized MCS may be effective to manage myopia efficiently. It shows AL evolution comparable to the documented natural evolution of emmetropes, especially when using customized or smaller treatment zone OK lens design. Future work on other populations will confirm this tendency.

Reduction of Myopic Progression Using a Multifocal Soft Contact Lens: A Retrospective Cohort Study

“…Although before and after treatment comparisons have limitations, they have been used to evaluate other myopia control interventions, as they are the only method of evaluating the efficacy of treatment in individual patients. [35][36][37][38] Comparisons to data in control groups 17,18,25,[39][40][41] and to the average progression of refractive error and axial length in virtual control groups of age and ethnicity matched patients from meta-analyses [30][31][32][33][34] can help gauge the success of…”

“…This approach of using an age and/or ethnicity matched virtual control group has been used in other studies to evaluate myopia control. [37][38][39][40][41] The mean refractive error and axial length progression for each child in the age and ethnicity matched virtual control group were calculated based on the data in the meta-analyses. [30][31][32][33][34] Both refractive error progression (P < 0.0001; Figure 2) and axial length elongation (P < 0.0001; Figure 3) were significantly lower throughout 3 years of wear of NVMF lenses compared with a virtual control group of age and ethnicity matched myopic children from published meta-analyses.…”

Retrospective Analysis of a Clinical Algorithm for Managing Childhood Myopia Progression

“…Observed changes in both cycloplegic spherical equivalent autorefraction and axial length were significantly lower than those predicted by virtual control data at 3 years, with projected CARE values of 0.11, 0.20, and 0.29 mm at 1, 2, and 3 years, respectively. Other researchers have used virtual control group comparisons to analyze the expected effectiveness of treatments for myopia control, including Chamberlain et al, 25 Lam et al, 29 and recently Michaud et al, 14 who retrospectively analyzed a myopia treatment protocol using multiple therapeutic modalities in 140 children.…”

“…Few studies have evaluated the success of defined treatment algorithms incorporating multiple therapeutic modalities customized to individual patients. Michaud et al 14 recently published data on the Montreal Experience, which presents one such algorithm. In this current study, we aimed to analyze the effectiveness of a unique myopia treatment protocol, referred to as the clinical treatment algorithm for myopic progression, over a period of up to 3 years.…”

Active illumination spectacle device slows childhood myopia progression

“…axial elongation between MiSight contact lens wearers and two virtual control groups aged 8-15 years,21 Lam et al compared efficacy of a passive spectacle myopia control design to historical control subjects,22 and Michaud et. al compared results with a custom myopia treatment protocol to a virtual control group of 140 children 23. Furthermore, available models for expected myopia progression in untreated myopic patients report annual…”