Korean J Ophthalmol Vol.25, No.3, 2011 conditions in an operating room. Postoperative antibiotics (ofloxacin; Tarivid, Santen, Japan) were applied four times per day for seven days. Each patient underwent a baseline screening, including slit-lamp examination and best corrected visual acuity (BCVA; logarithm of the minimum angle of resolution [logMAR]) testing, Cirrus OCT (Carl Zeiss Meditec, Dublin, CA, USA), and mfERG. One month after completion of the three in- jections, the patients were examined. All tests were per- formed on the same day. Cirrus OCT was performed with the 512 × 128 scan pattern. Research software (Research Browser ver. V.2.0.0.62, Carl Zeiss Meditec) was used to extract central macular thickness (CMT), including a circular 1-mm radius area around the fovea; total macular volume (TMV) was cal- culated from an area of 6 × 6 mm with the midpoint centered on the fovea. These calculations were based on the retinal segmentation algorithm of the Cirrus OCT prototype device. MfERG recordings were performed using VERIS ver. 4.2 (EDI, San Mateo, CA, USA). The patients’ pupils were di- lated using a mixture of 0.5% tropicamide and 0.5% phenyl- ephrine hydrochloride (Mydrin-P; Santen Pharmaceuticals, Osaka, Japan), and the eye to be tested was anesthetized us- ing proparacaine hydrochloride 0.5% (Alcaine; Alcon, Fort Worth, TX, USA). A Burian-Allen bipolar electrode was in- serted under 99% contrast and high luminance of 200 cd/m2. The stimulus matrix consisted of 103 hexagonal elements displayed on a CRT color monitor driven at 75 Hz. The filter setting band pass was 5 to 100 Hz and the duration of the data acquisition was 4 minutes divided into eight sessions of 30 seconds. The amplitude of each local response was estimated as the dot product between the normalized response template and each local response (scalar product method). The mfERG stimulus locations and anatomic areas corresponded roughly as follows: ring 1 to the fovea, ring 2 to the parafo- vea, and ring 3 to the perifovea (Fig. 1). The amplitude of each group was scaled to reflect the angular size of the stim- 50% Ring 3 Ring 2 Ring 1 ulus hexagon, which produces the response. These averages give a more accurate view of the relative response densities of each group. The recordings used the first-order kernel component of the mfERG, which is the largest mfERG re- sponse derived with a biphasic waveform characterized by an initial negative deflection (N1), followed by a positive peak (P1). This study included the amplitude and implicit time of N1 and P1 in rings 1, 2, and 3. To reduce errors by testers, on- ly one tester performed all tests and determined the peak points of responses. For the statistical analysis, the results from participants were analyzed by Wilcoxon's signed rank test in SPSS ver. 14.0 (SPSS Inc., Chicago, IL, USA). In addition, Spearman rank test and linear correlation analysis were used in order to evaluate the correlation with changes of mfERG components, the best visual acuity, and changes of OCT components. Differences and correlations were considered to be significant A Changes in best corrected visual acuity B Changes of central macular thickness C Changes of total macular volume Fig. 1. Stimulus array of 103 hexagonal elements; ring 1, ring 2, and ring 3 correspond to the fovea, parafovea, and perifovea, respectively. ILM = internal limiting membrane; RPE = retinal pig- ment epithelium. Fig. 2. Changes in best corrected visual acuity (A), central macular thickness (B), and total macular volume (C) before and after intra- vitreal injection (Wilcoxon's signed rank test, p < 0.05). logMAR = logarithm of the minimum angle of resolution. 162