Scleral buckling-induced ocular parameter changes in different age group patients of rhegmatogenous retinal detachment

Evaluation of the Effect of Scleral Buckling on Anterior Segment and Refractive Changes Using Anterior Segment Optical Coherence Tomography

PURPOSE

To evaluate the changes of anterior segment and refractive parameters after scleral buckling (SB) surgery for uncomplicated rhegmatogenous retinal detachment (RRD) using anterior segment optical coherence tomography (AS-OCT).

METHODS

Thirty-six RRD eyes were consecutively enrolled. Analysis concerned the central corneal thickness (CCT), anterior chamber depth (ACD), anterior chamber volume (ACV), iris-trabecular contact (ITC), angel opening distance (AOD), angle recess area (ARA), trabecular-iris space area (TISA)，trabecular iris angle (TIA) and refractive parameters, including average keratometry (AvgK), cylindrical power (CYL), regular astigmatism, asymmetry and high order irregularity (HOI) at baseline and 1 day, 1 month, 2 months, 6 months and 12 months postoperatively. AS-OCT was performed at RRD diagnosis and day 1, week 1, month 1 and month 6 after SB to evaluate the scleral buckling.

RESULTS

A statistically significant postoperative CCT increase, ACD and ACV decrease were observed at 1 day and 1 month postoperatively. ITC analysis showed that the angle of the entire circumference narrowed at 1 month postoperatively. There was a significant decrease in all the angle parameters (AOD500/750, ARA500/750, TISA500/750, and ARA500/750) at 1 day and 1 month after SB surgery. However, all of the above parameters returned to the preoperative level at 12 months. Refractive parameters including AvgK, regular astigmatism, CYL, asymmetry, and HOI of anterior corneal surface and total corneal increased on the 1 day and 1 month after SB surgery and persisted even after 12 months follow-up. However, there was no significant difference in refractive parameters of posterior corneal surface during follow-up.

CONCLUSION

The changes in the structure of anterior segments after SB surgery were almost returned to the preoperative levels at 12 months postoperatively. However, SB surgery has a long-term effect on refractive parameters throughout a 12-month follow-up.

Long-term changes in ocular rigidity following scleral buckling for rhegmatogenous retinal detachment

PURPOSE

To investigate the long-term effect of scleral buckling on corneal biomechanics and the effect of change of scleral properties on intraocular pressure (IOP) measurements.

METHODS

This is a prospective case series, patients with rhegmatogenous retinal detachment prepared for scleral buckling were included. Goldmann applanation tonometry was used to measure IOP (GAT IOP). Ocular Response Analyzer (ORA) was used to measure corneal hysteresis (CH), corneal resistance factor (CRF), goldmann-corrected IOP (IOPg), and corneal-compensated IOP (IOPcc) preoperatively, and 1, 3, and 6 months postoperatively.

RESULTS

Thirty-three eyes included in the final analysis, with an average age 38.4 ± 16.2 years. CH and CRF decreased significantly at first, third, sixth months post-scleral buckling; however, this effect decreased with time as follows; preoperative: 8.9 ± 1.5 and 8.5 ± 2.1, first month: 6.8 ± 1.6 and 7.1 ± 1.8 (P value = 0.00, 0.002), third month: 7.8 ± 1.5 and 7.6 ± 1.6 (P value = 0.001, 0.008), and sixth month: 7.7 ± 1.3 and 7.6 ± 1.7 (P value = 0.002, 0.055). IOP cc was 19.3 ± 3.6, 17.1 ± 4, and 17.6 ± 2.9 at 1, 3, and 6 months, and these readings were significantly higher than GAT (13.6 ± 7.6, 12.4 ± 5.1, and 12.1 ± 2.9, P values = 0.00) and IOPg (14.9 ± 3.6, 13.5 ± 4.1, and 13.9 ± 3.5, P values = 0.00). The change in CH at each visit is correlated with the difference between the IOPcc and GAT measurements.

CONCLUSION

The conventional Goldmann applanation tonometry underestimates post buckle IOP measurements due corneal biomechanics changes. ORA might be an alternative and accurate method of measurement; however, further investigation is warranted.

Choroidal vascular changes after encircling scleral buckling for rhegmatogenous retinal detachment

BACKGROUND/OBJECTIVES

There is an ongoing debate on whether encircling scleral buckling (SB) procedure for the treatment of rhegmatogenous retinal detachment (RRD) may cause an impairment in choroidal blood flow. The aim of this study was to compare choroidal vascularity index (CVI) and subfoveal choroidal thickness (CT) between eyes that had undergone encircling SB with unoperated fellow eyes (FEs).

SUBJECTS/METHODS

Thirty patients treated with encircling SB for unilateral RRD were included. Demographic and clinical characteristics as well as enhanced depth imaging-optical coherence tomography scans were retrospectively collected. Images were binarised using ImageJ software, total choroidal area along with luminal and stromal area (respectively, TCA, LA and SA) were segmented and the CVI was computed as the ratio of LA/TCA. In addition, CT was evaluated.

RESULTS

The mean follow-up interval between surgery and examination was 25.5 ± 16.8 months. Choroidal thickness, TCA, LA and SA were significantly increased in the operated eyes compared to FEs (respectively, 271.7 ± 78.0 µm vs. 238.5 ± 83.4, P = 0.001; 1.804 ± 0.491 mm² vs. 1.616 ± 0.496, P = 0.001; 1.199 ± 0.333 mm² vs. 1.067 ± 0.337, P < 0.001 and 0.605 ± 0.171 mm² vs. 0.550 ± 0.171, P = 0.001). Conversely, CVI did not significantly differ between the two groups (66.4 ± 3.6 vs. 65.9 ± 3.2, P = 0.490).

CONCLUSIONS

In conclusion, eyes treated with encircling SB for RRD presented increased LA, SA and CT compared with FEs, but showed no difference in CVI.

Corneal Biomechanical Response Alteration After Scleral Buckling Surgery for Rhegmatogenous Retinal Detachment

PURPOSE

To compare the corneal biomechanics of eyes that underwent scleral buckle (SB) for rhegmatogenous retinal detachment (RRD) with those of fellow eyes (fellow eyes) and to further investigate the effects of SB on intraocular pressure (IOP) values.

DESIGN

Retrospective, fellow-eye matched cohort study.

METHODS

A total of 18 consecutive patients (11 males and 7 females) treated with SB for RRD in 1 eye were enrolled. Goldmann applanation tonometry was used to measure IOP. Biomechanical properties of the cornea were investigated by using the Ocular Response Analyzer (ORA) (Reichert Instruments) for the calculation of corneal resistant factor (CRF), corneal hysteresis, Goldmann-correlated IOP, and corneal-compensated IOP. Customized software was used for analysis of the ORA infrared and pressure signals, and a significance threshold was set to a P value of .05.

RESULTS

Operated eyes (OEs) showed significantly lower values of corneal hysteresis and CRF than fellow eyes (9.0 ± 1.8 vs 10.1 ± 1.8 mm Hg, respectively; P < .001; 10.0 ± 2.2 vs 10.9 ± 2.2 mm Hg; P < .001). GAT was significantly lower than corneal-compensated IOP in OEs (18.1 ± 4.9 vs 19.8 ± 4.8 mm Hg, respectively; P = .022) but not in fellow eyes. The second applanation event (A2) took place earlier in time, and the cornea was moving faster during A2 in the OEs than in the fellow eyes.

CONCLUSIONS

SB for the treatment of RRD affects corneal biomechanical response, likely due to a less compliant sclera that limits corneal motion and reduces energy dissipation, reflected in a lower corneal hysteresis. This has potentially meaningful clinical implications as the accuracy of the measurement of IOP values may be affected in these eyes.

The effect of scleral buckling on accommodative amplitude

Purpose

To evaluate the effect of scleral buckling on accommodative amplitude.

Design

Non-randomized, prospective, double masked clinical trial in which the fellow eye of patients undergoing scleral buckling served as a control.

Methods

Patients who underwent scleral bucking for the management of retinal detachment in at least one eye were enrolled. Accommodative amplitude was measured monocularly 1 month and 3 months post operatively by two masked optometrists using a near-point "push" technique and minus-to-blur technique. Accommodative amplitude in eyes that underwent scleral buckle surgery were compared to their fellow eyes. Buckle type, buckle location, lens status and age were analyzed. Generalized Estimation Equations (GEE) were used to compare means and percentages between two groups.

Results

Seventy-four eyes of 37 patients were included in the study. Median age was 44 years old (range: 31-67 years old) and 68.4% of patients were male (n = 24). Two patients required bilateral surgery. Thirty-six of 39 operated eyes (92.3%) were phakic and three were pseudophakic. In phakic eyes there was a significantly higher amplitude of accommodation in operated eyes compared to their fellow eyes at post-operative month one (0.99 diopters, p value = 0.002) and three (1.17 diopters, p value = 0.001). The difference in accommodative amplitude in post-operative eyes compared to control eyes did not reach statistical significance in pseudophakic eyes nor did it differ between those who had an encircling band and those with a segmental buckle at both one and 3 months after surgery (p value = 0.37 and 0.38, respectively). In those with a segmental buckle, inferior fixation resulted in a larger difference in accommodative amplitude compared to control eyes than any other location fixation. Age under 40 years old and better post-operative best corrected visual acuity (BCVA) both correlated with greater difference in accommodative amplitude compared to fellow eyes.

Conclusion

Compared to fellow eyes not undergoing surgery, those eyes that underwent scleral buckling had a greater accommodative amplitude with larger differences correlating with better post-operative BCVA and younger age.

Refractive and Visual Outcomes and Rotational Stability of Toric Intraocular Lenses in Eyes With and Without Previous Ocular Surgeries: A Longitudinal Study

PURPOSE

To evaluate visual and refractive outcomes and rotational stability of toric intraocular lens (IOL) implantation in eyes with previous ocular surgeries.

METHODS

This controlled, longitudinal cohort study included a total of 133 eyes (59 study cases with a history of corneal, vitreoretinal, and/or glaucoma surgery and 74 randomly selected controls without a history of ocular surgery) that had cataract and corneal astigmatism treated with toric IOL implantation. Postoperative outcomes were recorded at postoperative 1 month and 3 to 12 months.

RESULTS

Refractive prediction errors were within ±1.00 diopter (D) of target in 93.5% and 88.4% of the study cases at postoperative 1 month and 3 to 12 months, respectively. They were within ±0.50 D of target in 56.5% and 60.5% of the cases during the same follow-up intervals, respectively. Study cases showed statistically significantly inferior uncorrected distance visual acuity (UDVA) compared to controls at 1 month postoperatively (0.27 ± 0.24 and 0.17 ± 0.21 logMAR, respectively, P = .027) but not during the later follow-up (0.19 ± 0.19 and 0.16 ± 0.19 logMAR, respectively, P = .431). Corrected distance visual acuity (CDVA) was slightly lower in the study cases than in controls at 1 month postoperatively (0.13 ± 0.16 and 0.07 ± 0.14, respectively, P = .005) and subsequent follow-up months (0.10 ± 0.13 and 0.03 ± 0.10, respectively, P < .001). Of the examined study cases, 93.9% and 88.4% had IOL axes within 5° of intended axis at postoperative 1 month and 3 to 12 months, respectively.

CONCLUSIONS

Toric IOLs provided significant and sustained improvement in visual acuity and refraction in eyes with a history of prior ophthalmic surgery. Refractive outcomes achieved postoperatively were comparable to those in eyes without a prior history of ophthalmic surgery, although the rate of visual recovery may be different. [J Refract Surg. 2019;35(12):781-788.].