Objective To observe the macular structure changes and its relationship with visual function in patients with idiopathic macular hole (IMH).Methods Forty-seven patients (47 eyes) with IMH who underwent pars plana vitrectomy were enrolled in this study.All patients were examined including best corrected visual acuity ( BCVA ), slit-lamp microscopy, indirect ophthalmoscopy, B-scan ultrasonography,optical coherence tomography (OCT) and MP-1.All the patients underwent a standard three-port pars plana vitrectomy.The BCVA,mean light sensitivity (MS) in macular area,macular hole diameter,the photoreceptor inner and outer segment (IS/OS) junction defect,external limiting membrane (ELM) defect were observed on the 1st,3rd and 6th months after surgery,and then the relationship of IS/OS junction defect,ELM defect,sensitive and BCVA were analyzed.Results The 1st,3rd and 6th months after surgery,the logarithm of minimal angle of resolution (logMAR) BCVA (t=16.4,35.7,20.7; P<0.05) and MS (t=-13.8,-17.9,-2.5; P<0.05) were improved significantly; the macular hole diameter (t=7.7,7.7,7.7; P<0.05),IS/OS junction defect (t=24.1,19.3,27.4; P<0.05) and ELM (t=20.5,6.7,15.8; P<0.05) defect were decreased significantly.Preoperative IS/OS junction defect and ELM defect were both related to sensitive (r=-0.55,-0.53; P<0.05),but uncorrelated with BCVA (r=0.13,0.13; P>0.05).IS/OS junction defect and ELM defect 1st,3rd and 6th months after surgery were both related to MS and BCVA (P < 0.05). Conclusions The logMAR BCVA and MS increase,while IS/OS junction and defect ELM defect decrease after surgery in IMH patients. IS/OS junction defect and ELM defect after surgery were both related to sensitive and BCVA. Key words: Retinal perforations/surgery; Vitrectomy; Treatment outcome