<p>Inter-Eye Vault Differences of Implantable Collamer Lens Measured Using Anterior Segment Optical Coherence Tomography</p>

Abstract

Purpose The distance between an implantable collamer lens (ICL) and the crystalline lens, namely vault, is a space regulated by the interaction of the ICL and the anatomical structures of the eye. This study analysed the differences in vault size between fellow eyes with similar anterior segment biometry. Patients and Methods A retrospective case series analysed 109 cases of patients bilaterally implanted with EVO-V4c. Patients were analysed pre- and postoperatively using anterior segment optical coherence tomography. The range of vault inter-eye differences was defined as the 95% confidence interval of the differences. Bivariate correlation was applied to seek for associations between vault inter-eye differences with biometric and lens parameters (angle-to-angle, anterior chamber depth, crystalline lens rise, central corneal thickness, central keratometry, ICL spherical equivalent, horizontal compression, postoperative pupil diameter and vault). Results Mean vault inter-eye differences were similar between fellow eyes (26.0 ± 122.5 µm). The 95% confidence interval range of the differences was ±240.1 µm, nearly 50% of the cases presented vault inter-eye differences higher than 100 µm. The vault of the first operated eye explained 81% of the variance in the second eye vault. Vault inter-eye differences were positively correlated with the level of horizontal compression and with vault magnitude. Conclusion Vaults measured in fellow eyes may present considerable differences, which can reach 25% of the common vault range. This reflects some degree of baseline variability in the vault. Clinically, these differences assume special relevance in cases where low or high vaults are expected.

Characteristics and factors associated with the position of the haptic after ICL V4C implantation

“…10 Manito et al compared the differences of clinical vault between the bilateral eyes, of which nearly 50% of eyes showed the differences higher than 100 μm. 11 They explained that the different intereye clinical vault may be due to the different position of ICL haptic which created different ICL arc. We think the formation mechanism of the clinical vault can be multifactorial, combining the ICL haptic-related parameters may be conducive to our understanding of clinical vault.…”

Vault differences in eyes implanted with spherical and toric implantable collamer lenses: an inter-eye analysis

“…In the present study, the limited number of eyes implanted with 12.6 and 13.7 mm ICLs may have restricted the ability for detecting the influence of ICL size on the vault. Nonetheless, the inter-eye comparisons showed no statistical and no clinical difference (repeatability for vault measurement ∼60 µm [ 38 ]) between sICL and tICL, with the inter-eye differences similar to those observed in fellow eyes implanted with the same ICL geometry [ 16 ]. The current results allow us advancing that the vault prediction for an ICL size is independent of the ICL optical geometry.…”

“…The ICL size and power were selected according to the manufacturer recommendations using the online calculator (OCOS™). The preoperative, postoperative and surgical protocol has been described elsewhere by our group [ 16 ]. This research followed the tenets of the Declaration of Helsinki and ethical approval was conceded by the local ethics committee (Comité Ético de Investigación Clínica de Badajoz).…”

“…The independent variables used in the GEE were selected based on the following criteria, (1) a single variable was chosen to describe a particular mechanism for the vault and (2) the variable chosen was the one presenting the highest association with the vault in the bivariate analysis. This study had a power of 0.951 to detect a difference of 80 µm (average of the differences between sICL and tICL reported in previous studies [ 12 , 13 , 15 ] and assuming a standard deviation of the differences equal to 120 µm [ 16 ]. Statistical analysis was performed using IBM SPSS Statistics V23.0.…”

Immediate or Delayed Sequential Bilateral ICL Surgery: a Survey of Chinese Ophthalmologists

“…This was another common concern for those who had never performed ISBICLS. Previous studies proposed that DSBICLS can be used to adjust the size of the second eye based on vault of the first eye 1 day after surgery, thus decreasing the risk of bilateral ICL size exchange [ 21 , 22 , 30 ]. According to our results, although the percentage of such cases was negatively associated with performing ISBICLS, most surgeons reported that it occurred less than 25% of the time.…”