METHODS: A total of 39 patients with myopia(74 eyes)who underwent SMILE surgery in our hospital during December 2018 to January 2019 were selected. They were divided into two groups: 23 patients(44 eyes)in low and medium myopia group(≤-6.00D)and 16 patients(30 eyes)in the high myopia group(>-6.00D). Changes of central anterior chamber depth(ACD), anterior chamber volume(ACV), anterior chamber angle(ACA), posterior central elevation(PCE), and accommodation amplitude(AMP)were observed in the two groups before the surgery and 1d, 1wk, and 1mo after surgery. The related data were statistically analyzed, and the changes before and after the surgery were compared. The causes of the morphological changes of the anterior chamber in the early stage after the SMILE were discussed.

RESULTS: The ACD before and 1d, 1wk, 1mo after surgery were 3.18±0.21, 3.10±0.21, 3.11±0.21 and 3.12±0.2mm, respectively, the ACV were 201.1±29.3, 187.9±27.1, 187±26.4 and 187.7±24.9mm3, respectively, the AMP were 8.4±2.6, 6.5±1.6, 7±1.7 and 8.3±1.9D, respectively, the ACD in the high myopia group before and 1d, 1wk, 1mo after surgery were 3.25±0.2, 3.18±0.19, 3.16±0.19 and 3.23±0.24mm, respectively, the ACV were 204.1±31mm3, 194.5±27mm3, 194.5±28.6mm3 and 196.5±31.7mm3, respectively, the AMP were 8.9±2D, 6.8±1.9D, 7.9±1.4D and 8.9±1.5D, respectively, the PCE 2.4±2.7μm, 1.4±2.7μm, 1.1±2.8μm and 1.4±2.9μm, respectively, the ACA were 42.40°±3.1°, 42.30°±3.6°, 42.10°±4.6°and 40.70°±4.5°, respectively. Pearson correlation analysis showed that postoperative ACD was positively correlated with ACA and ACV in both groups(P<0.01). ACD in the low myopia group was positively correlated with AMP(r=0.301, P<0.01), but weakly with PCE(r=0.161,P<0.05). ACD was not correlated with AMP and PCE in the high myopia group(r=0.069, 0.103, P>0.05).

CONCLUSION: In the early stage after SMILE, the diopter is different and the morphology of the anterior chamber is different. We believe that the change of ACD in the early stage after SMILE is related to changes of the corneal posterior elevation and postoperative accommodation.