The role of Müller cells in tractional macular disorders: an optical coherence tomography study and physical model of mechanical force transmission. Issue 4 (20th July 2019)

• Record Type: Journal Article
• Authors: Govetto, Andrea; Hubschman, Jean-Pierre; Sarraf, David; Figueroa, Marta S; Bottoni, Ferdinando; dell'Omo, Roberto; Curcio, Christine A; Seidenari, Patrizio; Delledonne, Giulia; Gunzenhauser, Robert; Ferrara, Mariantonia; Au, Adrian; Virgili, Gianni; Scialdone, Antonio; Repetto, Rodolfo; Romano, Mario R
• Is Part Of: British journal of ophthalmology. Volume 104:Issue 4(2020)
• Page Start: 466
• Page End: 472
• Publication Date: 2019-07-20
• Subjects: anatomy -- macula -- retina -- imaging; Ophthalmology -- Periodicals; 617.7
• DOI: 10.1136/bjophthalmol-2019-314245
• Languages: English
• ISSNs: 0007-1161

Abstract

Abstract : Background: To explore the role of foveal and parafoveal Müller cells in the morphology and pathophysiology of tractional macular disorders with a mathematical model of mechanical force transmission. Methods: In this retrospective observational study, spectral-domain optical coherence tomography images of tractional lamellar macular holes and patients with myopic foveoschisis were reviewed and analysed with a mathematical model of force transmission. Parafoveal z-shaped Müller cells were modelled as a structure composed of three rigid rods, named R1, R2 and R3. The angle formed between the rods was referred to as θ . R1, R2 and R3 lengths as well as the variation of the angle θ were measured and correlated with best corrected visual acuity (BCVA). Results: In tractional lamellar macular holes, there was a significant reduction of the angle θ towards the foveal centre (p<0.001). By contrast, there were no significant differences in θ in myopic foveoschisis (p=0.570). R2 segments were more vertical in myopic foveoschisis. There was a significant association between lower θ angles at 200 µm temporal and nasal to the fovea and lower BCVA (p<0.001 and p=0.005, respectively). The stiffness of parafoveal Müller cells was predicted to be function of the angle θ, and it grew very rapidly as the θ decreased. Conclusion: Parafoveal Müller cells in the Henle fibre layer may guarantee structural stability of the parafovea by increasing retinal compliance and resistance to mechanical stress. Small values of the angle θ were related to worse BCVA possibly due to damage to Müller cell processes and photoreceptor's axons.