Measurement of the depths at different regions of the anterior chamber in healthy Chinese adults

Measurement of Iris Thickness at Different Regions in Healthy Chinese Adults

Purpose

To study the variation of iris thicknesses in different regions and explore the possible correlations with age and gender.

Methods

Healthy Chinese adults were recruited; the anterior segment of their eyes was imaged by swept-source optical coherence tomography (SS-OCT). The horizontal scan of the right eye was selected, and the thicknesses of both the nasal and temporal irises were measured at 199 evenly spaced points.

Results

A total of 233 subjects with an average age of 36.79 ± 10.04 years (range 19 to 62) were included in the final analysis. The mean iris thicknesses of the temporal and nasal sides were 364.79 ± 47.58 μm and 372.44 ± 43.75 μm, respectively. The mean nasal iris thickness was positively correlated with age (β = 0.9 μm/year; P = 0.002), but the temporal one was not (β = 0.077 μm/year; P = 0.806). At 139 points of the nasal iris and 146 points of the temporal iris, the iris thickness was significantly correlated with age (P < 0.05). The thicknesses of the peripheral and pupillary parts were positively correlated with age, while the middle part was negatively correlated with age. No significant difference was observed in the mean iris thickness between genders (temporal: t = 1.597, P = 0.112; nasal: t = 1.870, P = 0.063), but females had a thicker iris than males at 50 points in the temporal side and 49 points in the nasal side (P < 0.05); no point in males was observed to have thicker iris compared to females.

Conclusion

Using SS-OCT and the novel method, thicknesses of the iris at different regions were measured. The thicknesses of the peripheral and pupillary irises increase with age, while the thicknesses of the middle part decrease.

Comparison of Femtosecond Laser-Assisted Cataract Surgery and Conventional Phacoemulsification in Shallow Anterior Chambers and Glaucoma

Purpose

To compare femtosecond laser-assisted cataract surgery (FLACS) versus conventional phacoemulsification in shallow anterior chamber cataract patients with glaucoma or zonulysis.

Methods

This was a single-center retrospective review of cataract surgeries in shallow anterior chamber and glaucoma patients between January 2016 and December 2018 in which a LenSx femtosecond laser was used. The outcome measures included pre- and postoperative uncorrected and corrected distance visual acuity (UDVA and CDVA), intraocular pressure (IOP), endothelial cell density (ECD), endothelial cell loss (ECL), and object scatter index (OSI).

Results

One hundred and six eyes of 106 patients with a mean anterior chamber depth of 1.54 ± 0.51 mm were included in this study. Among them, 26 (23.2%) had zonulysis and 18 eyes had capsular tension ring implantation in general. The percentage of capsular tension ring implantation was statistically significantly lower in the FLACS group (P = 0.027). The UDVA, CDVA, ECD, and IOP were not statistically significant between the two groups at all time points. The postoperative ECL and OSI of the FLACS group was better than those of the conventional group (P < 0.01).

Conclusions

FLACS can reduce ECL and improve visual quality compared to the conventional phacoemulsification in shallow anterior chamber patients. Also, it has the trend of reducing the use of capsular tension rings in subluxated cataracts. It is an ideal choice for patients with complicated cataract such as with shallow anterior chambers, glaucoma, and zonulysis.