Evaluation of posturing in macular hole surgery

Aim To objectively evaluate the postoperative face down posturing in macular hole surgery. Materials and Methods An electronic device called 'Maculog' was developed consisting of three basic components, a mercury switch triggered by the angle of tilt placed inside an earpiece, a data-recording device connected to the earpiece with cables and a windows based software program, specially written to analyse the recorded data in the form of tables and graphs. Ten patients undergoing macular hole surgery were fitted with the device on the first postoperative day before discharge. They were also asked for a subjective record of their posturing times. Four patients were given a posturing chair to take home. The device was retrieved after the first week and the data were downloaded to a PC for analysis. The actual posturing times recorded on the device were compared to the patients' own recollections. Results In all ten patients the actual posturing time was less than the time they had recorded themselves. The average actual posturing time was 48% of the perceived posturing time. The worst time for posturing, as expected, was between midnight and early morning. The compliance was better in patients who used the posturing chair. Conclusions It is feasible to quantify the time of posturing using an electronic device and computer analysis. The study has shown that the actual posturing time is significantly less than the perceived posturing time. A further large study using 'Maculog' is now planned to correlate actual posturing time to the results of macular hole surgery.