The correlation analysis of morphological parameters and postoperative prognosis in patients with idiopathic macular hole

Abstract

Objective To evaluate the optical coherence tomograghy (OCT) morphological parameters for predicting anatomical outcomes and postoperative visual acuity in idiopathic macular hole (IMH) after pars plana vitrectomy (PPV). Methods A retrospective study. A total of 26 eyes in 23 IMH patients underwent PPV, internal limiting membrane (ILM) peeling and gas filling surgery were included in this study. The patients included 8 eyes of 7 males and 18 eyes of 16 females, with the mean age of (63.9± 9.4). All patients received the best corrected visual acuity (BCVA), slit lamp microscope, indirect ophthalmoscopy and three-dimensional optical coherence tomography (3D OCT) examinations. The BCVA was measured using the international standard visual acuity chart, and the results were converted to the logarithm of the minimum angle of resolution visual acuity. According to the standard classification system of International Vitreomacular Traction Study (IVTS) Group, 8 eyes were medium full-thickness macular hole (FTMH) and 18 eyes were large FTMH, none of which were with vitreomacular traction (VMT). The minimum diameter (MIN), base diameter (BASE), height (H), left and right arm length (LAL and RAL), diameter of ellipsoid zone absence (DEZA) were measured. Macular hole index (MHI), hole form factor (HFF), tractional hole index (THI), diameter hole index (DHI) were calculated. The average follow-up period were (9.2±9.7)months. The postoperative DEZA were measure at the last time. Anatomical outcomes were divided into 3 groups. The multiple factors related with predicting anatomical outcome and visual acuity were analyzed. Results In the 26 eyes, the hole was closed in 16 eyes of type 1, 7 eyes of type 2, 3 eyes of type 3. The mean pre- and post-operative logMAR BCVA were 0.9±0.3, 0.7± 0.3 respectively. The MIN, BASE, H were (533±176), (1 035±270), (462±138)μm respectively. The MHI, HFF, THI, DHI were 0.46±0.15, 0.72±0.19, 0.95±0.37, 0.52±0.11 respectively. The mean pre- and post-operative DEZA were (1 775±486), (960±138) μm respectively.Postoperative logMAR BCVA were correlated significantly with MHI, THI (all P 0.05). Anatomical prognosis types were significantly correlated with MHI, HFF, THI (all P 0.05). Conclusions For medium and large FTMH in IVTS classification system, MHI, THI have the best correlation with postoperative BCVA and can be considered as key indicators for predicting postoperative BCVA. MHI, HFF, THI have the best correlation with anatomical outcomes and can be considered as key indicators for predicting anatomical outcomes of IMH. Key words: Retinal perforations; Tomography, optical coherence; Vitrectomy; Retina