Wenbo Cheng1, Lingjia Liu2, Shasha Yu1,3, Yin Jing4, Tong Zuo4, Tong Cui1, Hui Zhang4, Jiaonan Ma1, Pinghui Wei4, Weiting Hao1, Alex Lap-Ki Ng3, George Pak-Man Cheng5, Victor Chi-Pang Woo5, Kin Chiu3,6, Yan Wang1,2,4. 1. a Clinical College of Ophthalmology , Tianjin Medical University , Tianjin , China. 2. b Medical College of Nankai University , Tianjin , China. 3. c Department of Ophthalmology, LKS Faculty of Medicine , The University of Hong Kong , Hong Kong SAR , China. 4. d Tianjin Eye Hospital & Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science , Clinical College of Ophthalmology , Tianjin , China. 5. e Hong Kong Laser Center , Hong Kong SAR , China. 6. f State Key Laboratory of Brain and Cognitive Sciences , The University of Hong Kong , Hong Kong SAR , China.
Abstract
PURPOSE: To investigate real-time intraocular pressure (IOP) during small incision lenticule extraction (SMILE) in rabbit eyes for myopia correction. METHODS: During SMILE, real-time IOP was measured in the vitreous cavity of rabbit eyes with an optic fiber pressure sensor (OFPS). Two groups (n = 6 for each) underwent surgery, one group for a -2.00 diopter (D) refractive spherical correction and the other for a -6.00 D correction. RESULTS: During surgery, the IOP increased once the glass contact attached to the cornea (Pre-suction), and peaked 83.94 mmHg (SD ± 23.87 mmHg) for the -2.00 D group and 89.17 mmHg (SD ± 22.66 mmHg) for the -6.00 D group, both average values were less than 110 mmHg when suction was initiated to fix the glass contact onto the cornea (Suction on). It then fell to 74.81 mmHg (SD ± 20.64 mmHg) and 76.94 mmHg (SD ± 27.43 mmHg), respectively, and remained stable during lenticule creation (Cutting). After suction stopped (Suction off), IOP fell steeply. During lenticule separation/extraction, the change in IOP was 32.26 mmHg (SD ± 2.91 mmHg). Notably, the average duration of elevated IOP during the surgery was 166.05 s (no longer than 3 min). CONCLUSIONS: The IOP fluctuations in the vitreous cavity using an OFPS in a rabbit model during SMILE showed that real-time IOP significantly was increased during Pre-suction, Suction on, Cutting, Suction off, and lenticule separation/extraction compared to baseline IOP, although, peaked at Suction on. Neither the degree of myopic correction nor central corneal thickness significantly affected these changes in IOP.
PURPOSE: To investigate real-time intraocular pressure (IOP) during small incision lenticule extraction (SMILE) in rabbit eyes for myopia correction. METHODS: During SMILE, real-time IOP was measured in the vitreous cavity of rabbit eyes with an optic fiber pressure sensor (OFPS). Two groups (n = 6 for each) underwent surgery, one group for a -2.00 diopter (D) refractive spherical correction and the other for a -6.00 D correction. RESULTS: During surgery, the IOP increased once the glass contact attached to the cornea (Pre-suction), and peaked 83.94 mmHg (SD ± 23.87 mmHg) for the -2.00 D group and 89.17 mmHg (SD ± 22.66 mmHg) for the -6.00 D group, both average values were less than 110 mmHg when suction was initiated to fix the glass contact onto the cornea (Suction on). It then fell to 74.81 mmHg (SD ± 20.64 mmHg) and 76.94 mmHg (SD ± 27.43 mmHg), respectively, and remained stable during lenticule creation (Cutting). After suction stopped (Suction off), IOP fell steeply. During lenticule separation/extraction, the change in IOP was 32.26 mmHg (SD ± 2.91 mmHg). Notably, the average duration of elevated IOP during the surgery was 166.05 s (no longer than 3 min). CONCLUSIONS: The IOP fluctuations in the vitreous cavity using an OFPS in a rabbit model during SMILE showed that real-time IOP significantly was increased during Pre-suction, Suction on, Cutting, Suction off, and lenticule separation/extraction compared to baseline IOP, although, peaked at Suction on. Neither the degree of myopic correction nor central corneal thickness significantly affected these changes in IOP.
Entities:
Keywords:
Intraocular pressure; cornea; in vivo; myopia; refractive surgery