[The observation on detachment of posterior hyaloid membrane in idiopathic macular holes by optical coherence tomography].

OBJECTIVE

To investigate the relationship of the detachment of posterior hyaloid membrane and idiopathic macular hole by optical coherence tomography (OCT).

METHODS

Fundus examination after dilatation of pupil and OCT were performed on 223 eyes of 193 patients with idiopathic macular hole. All macular holes were graded according to the classification proposed by Gass.

RESULTS

According to Gass classification, there were 21 eyes of stage I macular hole, 74 eyes of stage II, 97 eyes of stage III and 31 eyes of stage IV. OCT showed the detachment of posterior hyaloid membrane in 15 eyes (71.4%) in stage I, 38 eyes (51.4%) in stage II and 46 eyes (47.4%) in stage III. There were three kinds of imaging characteristics: (1) Perifoveal detachment of posterior hyaloid membrane (hyporeflective band) with a cyst (hyporeflective cavity) in the center of fovea and the elevating or flattening of fovea by the traction of posterior hyaloid. (2) The posterior hyaloid (hyporeflective band) adhered to the partially detached operculum (hyporeflective band) that was pulled forward. (3) The complete detachment of posterior hyaloid from the retina was seen. In some cases, the OCT image showed the development of macular hole from stage I to stage III. A scan along the papillomacular axis showed that the posterior vitreous detachment was dome shaped with the adhesion to fovea and disc.

CONCLUSIONS

The occurrence of posterior hyaloid detachment at the fovea is in accordance with the formation of macular hole.