A 36-year-old woman diagnosed with myopia presented for the evaluation of refractive surgery. She was a teacher with no history of systemic or ocular disease or surgery. The anterior segment and fundus evaluations, including slit-lamp bio-microscopy and indirect ophthalmoscopy (+ 90 D lens), were normal in both eyes. The patient’s uncorrected distance visual acuity (UDVA) was 1/20 in both eyes, with refractive error of -8.00 DS/-2.00 DC * 8° in the right eye and − 6.50 DS/-1.75 DC * 177° in the left eye. IOP was 15.9 and 15.2 mmHg in the right and left eye, respectively, measured using applanation tonometry (TX-F; Canon, Tokyo, Japan). The corneal topography was measured using a rotating Scheimpflug camera (Pentacam HR, Oculus, Germany). Keratometric values were 43.5@100/41.5@10 and 43.2@92/41.3@2, the anterior chamber depth (ACD) was 3.35 and 3.37 mm, central corneal thickness (CCT) was 505 and 501 μm for the right and left eye, respectively. White-to-white (WTW) distance was 11.9 mm for both eyes, while WTW measured using Zeiss IOL-Master 700 was 12.2 mm for both eyes. Horizontal sulcus-to-sulcus (STS) distance assessed by the UBM (Ultrasound Biomicroscope, Model SW-3200 L; Tianjin Suowei Electonic Technology Co, Ltd., Tianjin, China) were 12.28 mm and 12.13 mm for the right and left eye, respectively. The endothelial cell density (ECD), calculated by the non-contact autofocus specular microscope (EM-3000, Tomey Corp., Nagoya, Japan), was 2664 cells/mm2 in the right eye and 2557 cells/mm2 in the left eye (automatic method was used for endothelial count analysis). After a thorough discussion with the patient regarding the risks and benefits of surgery, we obtained informed consent for surgery. Toric ICL-V4Cs (Visian ICL with Centraflow; STAAR Surgical) were chosen for horizontal implantation, with a power of -10.50 DS/+ 2.00 DC * 99° and 1° clockwise rotation in the right eye and − 9.00 DS/+ 1.50 DC * 88° and 1° clockwise rotation in the left eye (VTICMO13.2 SN: T564197 for the right eye, VTICMO13.2 SN: T557998 for the left eye). Preoperatively, 0° and 180° limbus reference markings were made under a slit lamp, and the surgery was performed under pupil dilation. After administration of topical anesthesia (0.5% proparacaine hydrochloride eye drops; Ruinian Best, Nanjing, China, with no preservatives), two side-ports (1.0 mm in size) and a 3.0 mm vertical clear corneal main incision were made. One side-port incision was used for continuous infusion of balanced salt solution (BSS) [] by the patent irrigator to maintain the anterior chamber, and the other was used for tucking the footplates by the patent manipulator. The TICL was inserted through the main incision with four haptics tucked beneath the iris, and subsequently adjusted to the desired alignment axis. No ophthalmic viscosurgical devices (OVDs) were used during surgery. The patient was discharged two hours after bilateral TICLs implantation, with a clear cornea, mid-dilated pupil, and UDVA of 6/20 and 10/20. The IOP was 28 and 25 mmHg in the right and left eye, respectively; therefore, the patient was called for follow-up the next day. On the first postoperative day, both eyes achieved a UDVA of 20/16 with IOP of 16 and 19 mmHg, while the vault was 1238 and 1198 μm for the right and left eye, respectively. Anterior segment examination revealed an endothelial annular lesion of approximately 0.4 mm in diameter in the central part of the cornea, gray-white in color, in the right eye. The epithelium was intact without any damage. The anterior chamber was quiet without signs of anterior ocular chamber inflammation. Automatic specular microscopy showed that the mean ECD of the ring was significantly decreased to 1442 ± 263 cells/mm2 with abnormal endothelial cell morphology in the lesion part, whereas in the peripheral part of the cornea, it was 2852 ± 103 cells/mm2. The patient was instructed to apply tobramycin and dexamethasone eye drops (ALCON, Novartis Pharma NV, Belgium), 6 times a day, and pranoprofen (Senju, Pharmaceutical Co. Ltd., Japan), 4 times a day, postoperatively. She was also administered vitamin A palmitate eye gel (Novartis Ophthalmics AG, Switzerland), 4 times a day, and 0.3% sodium hyaluronate eye drops (Santen Pharmaceutical Co. Ltd., Japan), 6 times a day, to maintain the tear film and a regular ocular surface. At the 9th day of follow-up for the right eye (in both eyes), the UDVA was 20/16, and the cornea was clear; the mean ECD of the central part increased to 1532 ± 257 cells/mm2. In addition, a partial endothelial cell loss was still observed, but with a better endothelial cell morphology. IOP and vault for the right and left eyes were 16 and 13 mmHg and 1162 and 1083 μm, respectively. Topical dexamethasone tobramycin was replaced with 0.1% fluorometholone 10 days postoperatively and then tapered slowly over the next 3 weeks (1-day, 9-day, 40-day, 4-month, and 9-month postoperative data of the right eye are presented in Table, CCT changes measured by two different instruments are shown in Table ).