Macular hole is a full thickness retinal defect in the very centre of the retina that gives the sharpest vision. The condition causes a substantial deterioration of visual acuity, and operative measures are necessary in order to close the defect and improve the visual function. A macular hole has varying degrees of retinal oedema surrounding the hole edges. The oedema is maintained by continuous of liquid into the tissue and effectively prevents spontaneous closure. For that reason it is essential for macular hole closure that the macula has minimal contact with intraocular fluid in the very early postoperative phase. This is why the treatment included a long-lasting intraocular gas tamponade and typically, one week of face-down positioning (FDP) after surgery.Our aim is to investigate the impact of diurnal, orthostatic, and gravitational variations on macular hole morphology before and after surgery. The participants will be examinated with optical coherence tomography 8-10 am, 1 pm, and 3 pm. Between 8 am and 1 pm ,the patient is encouraged to an upright position. After the 1 pm examination, the patient will be positioned flat on the side of the eye with macular hole until the 3 pm examination. The surgery will be performed before 10 am. Postoperatively a randomization to face down positioning or no positioning until 3 am. Optical coherence tomography images through gas tamponade is made at 3 am.

Inclusion Criteria:

• Primary macular hole
• Able to sign informed consent
• Signed informed consent

Exclusion Criteria:

• Previous vitreoretinal surgery in the study eye
• Secondary macular holes caused by other conditions than vitreomacular traction
• Myopic macular hole, i.e. excessive myopia (more than -6 dioptres)
• Posttraumatic macular hole
• Macular holes secondary to retinal detachment or other retinal diseases