Long-term follow-up of persistent low vault after implantable collamer lens exchange.

The implantable collamer lens (ICL) is a widely used posterior chamber phakic intraocular lens that achieves excellent refractive results. Nonetheless, serious postoperative complications related to inadequate vault have been previously reported. Therefore, lens exchange is advised when the vault is out of the recommended ranges. This article presents a case with persistent low vault after lens exchange in which no clinical evidence of crystalline lens opacity or decrease in uncorrected distance visual acuity has been identified during the 6-year clinical follow-up performed to date. Therefore, this suggests that clinical follow-up could be an appropriate approach for patients presenting with low vault, especially those who are older than 40 years and have a history of lens exchange.

Anterior segment optical coherence tomography angle and vault analysis after toric and non-toric implantable collamer lens V4c implantation in patients with high myopia.

OBJECTIVE: To assess anterior segment changes, including iridocorneal angle and vault, after toric and non-toric implantable collamer lens (ICL) V4c (STAAR Surgical AG) implantation under different lighting conditions. METHODS: Longitudinal, prospective, case series. Patients with high myopia (>6 dioptres) underwent toric and non-toric ICL V4c implantation. Optical coherence tomography measurements were taken under different lighting conditions preoperatively and at 1 week and 1, 6 and 12 months of follow-up. RESULTS: Seventy-six eyes of 42 patients underwent ICL V4c implantation. Mean age was 27.4 years (±5.14 years, range 20 to 39 years). The average iridocorneal angle showed a statistically significant decrease (p<0.05) in all mesopic, scotopic and photopic conditions after 1 week of surgery compared with the preoperative measurements; in mesopic conditions, it decreased 14.1°, in photopic conditions 14.8° and scotopic conditions 13.2°. The angle measurement had a statistically significant change only in mesopic conditions (p=0.01) over the 1-year follow-up. The average vault under mesopic conditions was 0.661±0.21 mm at week 1. The vault measurement change was statistically significant over the 1-year follow-up in mesopic conditions (p=0.01). Refractive results showed a significant improvement in both uncorrected and corrected distance visual acuity (p<0.001). CONCLUSION: There is a significant reduction in the iridocorneal angle after ICL V4c implantation. Furthermore, there is a change under mesopic conditions in both the iridocorneal angle and vault during long-term follow-up.

Long-term refractive outcomes of posterior chamber phakic (spheric and toric implantable collamer lens) intraocular lens implantation.

To report the long-term refractive outcomes, safety, predictability, efficacy and complications of 349 eyes treated with posterior chamber phakic intraocular lenses (pIOLs). A retrospective review of consecutive clinical cases of patients who underwent spheric implantable collamer lens (ICL) and toric ICL (TICL) implantation. The study included 349 eyes of 216 patients with sphere between +8 to -24 diopters (D) and 0 to -6.5 D of astigmatism. Statistical analysis was performed to identify differences between preoperative and postoperative refractive outcomes. Main outcome measures were preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical and cylindrical errors and spherical equivalent and significant postoperative complications. 194 eyes were treated with TICL and 155 eyes with ICL. The mean age of the patients was 29 ± 6.7 years. The mean preoperative sphere was -10.35 ± 5.1 D (+8 to -24) and the postoperative sphere was -0.09 ± 1.06 D (+3.25 to -6.5), p < 0.001. Preoperative cylinder was -2.63 ± 1.44 (0 to -6.5 D) and postoperative cylinder was -0.97 ± 0.89 D (0 to -3.5), p < 0.001. The preoperative mean spherical equivalent was -11.6 ± 5.12 D (+7.875 to -25.625) and postoperative spherical equivalent was -0.52 ± 1.03 (+2.25 to -6.75), p < 0.001. The mean preoperative UDVA was 1.72 ± 0.49 and postoperative UDVA was 0.23 ± 0.22, p < 0.001. The mean preoperative CDVA was 0.21 ± 0.17 and postoperative CDVA was 0.12 ± 0.138, p < 0.001. The implantation of posterior chamber pIOLs is a safe, predictable and effective strategy to manage refractive errors during long-term follow-up.

DSAEK for implantable collamer lens dislocation and corneal decompensation 6 years after implantation.

A 39-year-old woman with a history of high myopia underwent uneventful implantation of phakic posterior chamber implantable collamer lenses (ICLs) 6 years earlier in both eyes with a visual acuity of 20/20 bilaterally. The patient presented as an emergency with sudden decreased vision in her right eye after blunt trauma. Slit-lamp examination showed a partially dislocated ICL in the anterior chamber, associated with ocular hypertension. It was decided to treat her with topical ocular hypotensive agents and surgical repositioning of the ICL. There was a progressive loss of endothelial cells and decreased visual acuity. Descemet stripping automated endothelial keratoplasty was needed to correct the endothelial failure. This case presents a potential complication of the ICL several years after implantation, and should be considered in these types of procedures.

Implantable collamer lenses after intracorneal ring segments for keratoconus.

To report the clinical characteristics and visual outcomes of patients with keratoconus treated with posterior chamber phakic intraocular lenses after implantation of intracorneal ring segments (ICRS). This retrospective study included 11 eyes of eight patients diagnosed with keratoconus treated with ICRS and posterior chamber phakic intraocular lenses. The preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), preoperative and postoperative keratometric data, manifest refraction and spherical equivalent were recorded. No complications were observed. At 38.18 ± 18.7 months of follow-up, the mean spherical error was -0.06 ± 0.46 D (+0.75 to -0.75 D) and cylindrical error of -1.22 ± 0.65 D (-0.25 to -1.5 D). The preoperative spherical equivalent was -10.52 ± 5.88 D (-3.12 to -22.75 D) and the postoperative spherical equivalent was -0.68 ± 0.45 D (0 to -1.25 D), p < 0.001. The preoperative and postoperative UDVA were 1.31 ± 0.37 logMAR (mean 20/400 Snellen, 0.69-1.77 logMAR) and 0.14 ± 0.04 (mean 20/30 Snellen, 0.09-0.47 logMAR), with a p value <0.001. The preoperative and postoperative CDVA were 0.289 ± 0.14 logMAR (mean 20/40 Snellen, 0-0.477 logMAR) and 0.16 ± 0.08 (mean 20/25 Snellen, 0.09-0.39 logMAR), with a p value of 0.007. Combined treatment of keratoconus with ICRS and posterior chamber phakic intraocular lenses was a safe and effective procedure for high refractive errors induced by keratoconus in these selected patients.

Spontaneous Rotation of a Toric Implantable Collamer Lens.

We present a case of toric implantable collamer lens (TICL) spontaneous rotation in a patient with myopic astigmatism. A 23-year-old female underwent TICL implantation. Preoperative uncorrected visual acuity (UCVA) was 20/800 and 20/1200, respectively, with -7.75 -4.25 × 0° and -8.25 -5.25 × 180°. The left eye achieved an UCVA of 20/30. After 3 months of successful implantation of TICL in the left eye, the patient presented with a sudden decrease in visual acuity in the left eye. UCVA was 20/100 with a refraction of +2.50 -4.50 × 165°. We observed the toric marks with a 30° rotation from the original position and decided to reposition the TICL, obtaining a final UCVA of 20/25, which remained stable at 6 months' follow-up. TICL can present a considerable rotation that compromises visual acuity. The relocation of TICL is a safe and effective procedure to recover visual acuity due to significant spontaneous TICL rotation.