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Purpose: To document with spectral domain optical coherence tomography the formation and spontaneous closure of small full‐thickness macular holes and to propose the active role of Müller cells in macular hole closure. Methods: A retrospective case series of five patients with spontaneous closure of macular holes is reviewed. In one patient, foveal images were recorded over a period of 18 months. Results: In a 66‐year‐old man, vitreofoveal traction caused a detachment of the inner Müller cell layer of the foveola from the outer nuclear layer (ONL) which was associated with a large pseudocyst and a horizontal gap in the central ONL. The traction caused an elongation and subsequent disruption of the stalk of the Müller cell cone in the foveola. A small full‐thickness macular hole developed when a portion of the inner Müller cell layer of the foveola was pulled out. After phacoemulsification and shortly before the subsequent spontaneous closure of the hole, there were rapid increases in the number and size of the cystic cavities in the foveal walls resulting in a narrowing of the hole. The hole closed by bridging the gap in the inner part of the central ONL; a new inner Müller cell layer of the foveola was formed, and the gap of the external limiting membrane (ELM) was closed. The cystic cavities in the foveal walls rapidly disappeared within 2 weeks after the closure of the hole. One to 2.5 months after hole closure, the thickness of the central ONL increased which decreased the distance between the central ELM and retinal pigment epithelium. In three of the four other patients, the hole also closed by bridging the gap in the inner part of the ONL. Conclusion: It is suggested that the spontaneous closure of small macular holes and the subsequent reconstruction of the normal foveal structure are mediated by active mechanisms of Müller cells which resemble those involved in ontogenetic foveal development. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the ploughing mechanism associated with tractional force formation on the temporomandibular joint (TMJ) disc surface.Setting and Sample Population: Ten left TMJ discs were harvested from 6- to 8-month-old male Yorkshire pigs.Materials and Methods: Confined compression tests characterized mechanical TMJ disc properties, which were incorporated into a biphasic finite element model (FEM). The FEM was established to investigate load carriage within the extracellular matrix (ECM) and the ploughing mechanism during tractional force formation by simulating previous in vitro plough experiments.Results: Biphasic mechanical properties were determined in five TMJ disc regions (average±standard deviation for aggregate modulus: 0.077±0.040 MPa; hydraulic permeability: 0.88±0.37×10-3 mm4 /Ns). FE simulation results demonstrated that interstitial fluid pressurization is a dominant loading support mechanism in the TMJ disc. Increased contact load and duration led to increased solid ECM strain and stress within, and increased ploughing force on the surface of the disc.Conclusion: Sustained mechanical loading may play a role in load carriage within the ECM and ploughing force formation during stress-field translation at the condyle-disc interface. This study further elucidated the mechanism of ploughing on tractional force formation and provided a baseline for future analysis of TMJ mechanics, cartilage fatigue and early TMJ degeneration. [ABSTRACT FROM AUTHOR]