Changes in ocular biometric measurements after vitrectomy with silicone oil tamponade for rhegmatogenous retinal detachment repair

A Comparison of Adjustable Positioning and Free Positioning After Pars Plana Vitrectomy for Rhegmatogenous Retinal Detachment: A Prospective Randomized Controlled Study

Purpose

To compare the effectiveness and safety of adjustable and free postoperative positioning after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD).

Design

Prospective, randomized controlled study.

Methods

A total of 94 eyes with RRD were enrolled from April 2020 to April 2023 and monitored postoperatively for at least 3 months. All patients underwent PPV combined with silicone oil injection or gas tamponade and were randomly divided postoperatively into two groups: an adjustable positioning group and a free positioning group. The success of the outcome was based on the retinal reattachment rate, best corrected visual acuity (BCVA), postoperative complications, and ocular biometric parameters such as anterior chamber depth (ACD) and lens thickness (LT).

Results

The initial retinal reattachment rate was 97.9% in the adjustable positioning group and 95.7% in the free positioning group, manifesting no statistical difference between the two groups. Similarly, no statistical difference was observed between the two groups in the final BCVA, which was significantly improved compared to the preoperative BCVA. The comparison of the 1-month postoperative ACD and LT with the preoperative values showed no statistically significant differences in the two groups. The rates of complications were not statistically different in the two groups.

Conclusion

After treating RRD using PPV, neither the adjustable nor the free postoperative positioning affected the retinal reattachment rate or the incidence of complications. Therefore, our study showed that it is safe and effective to adopt free positioning postoperatively, which may provide more options for patients with RRD undergoing PPV.

Intraocular lens power calculation for silicone oil-dependent eyes

Background

Silicone oil tamponade is widely used in vitreoretinal surgery. In some cases, silicone oil may not be extracted for a long time or even permanently and is referred to as silicone oil-dependent eyes. In this study, we aimed to deduce a theoretical formula for calculating intraocular lens power for silicone oil-dependent eyes and compare it with clinical findings.

Methods

A theoretical formula was deduced using strict geometric optical principles and the Gullstrand simplified eye model. The preoperative and postoperative refractive statuses of patients with silicone oil-dependent eyes who underwent intraocular lens implantation were studied (Group A, n = 13). To further test our derived theoretical formula, patients with silicone oil tamponade and first-stage intraocular lens implantation were included (Group B, n = 19). In total, 32 patients (32 eyes) were included in the study.

Results

In group A, the calculated intraocular lens power based on our formula was 24.96 ± 3.29 diopters (D), and the actual refraction of the patients was 24.02 ± 4.14D. In group B, the theoretical intraocular lens power was 23.10 ± 3.08D, and the clinical intraocular lens power was 22.84 ± 3.42D. There was no significant difference between the theoretical and clinical refractive powers, and the intraclass correlation coefficient was 0.771 for group A and 0.811 for group B (both p ≤ 0.001). The mean absolute error for silicone oil-dependent eyes of the formula was 1.66 ± 2.09D. After excluding data for two patients with a flat cornea (corneal refractive power < 42D), the mean absolute error decreased to 0.83 ± 0.62D.

Conclusion

A strong correlation between the theoretical and clinical intraocular lens powers was observed, and the formula we deduced can be used to calculate the intraocular lens power for silicone oil-dependent eyes. This formula will help clinicians select a more appropriate intraocular lens for patients with silicone oil-dependent eyes, especially when the corneal refractive power is ≥42D.

How should we report the foveal status in eyes with "macula-off" retinal detachment?

Whilst pre- and postoperative multimodal imaging technologies including optical coherence tomography (OCT) have investigated the morphological correlates of worsened visual outcomes in rhegmatogenous retinal detachment (RRD) with foveal involvement, the nomenclature has adhered to the traditional ophthalmoscopy-based and rather vague term "macula-off". This article appraises the current literature with regard to the preoperative assessment and nomenclature of the foveal status in macula involving retinal detachment (MIRD). A literature review of recent publications assessing functional or morphological outcomes in MIRD was conducted, using the search terms "fovea-off" or "macula-off". The search date was April 28^th, 2021. Original studies in English language were included. Case reports, review articles or letters were excluded. Forty relevant articles (range of publication dates: July 29^th, 2020 - April 18^th, 2021) were reviewed to assess the diagnostic modalities used, morphological parameters assessed, and any specific nomenclature introduced to specify the extent of macular detachment. The results suggest widespread variability and inconsistencies with regard to the preoperative assessment, diagnostic modalities and nomenclature used to describe the foveal status in eyes with RRD termed "macula-off". The extent of macular detachment may be classified by a wide range of morphological parameters, including the height of foveal detachment and the ETDRS grid as overlay tool in OCT devices. There is a scientific and clinical need for an updated nomenclature for eyes with "macula-off" RRD. Preoperative OCT findings should be reported on a regular and standardized basis in order to establish a consensus how to report the foveal status in eyes with MIRD.

Intralenticular Ozurdex injection in an eye with thicker lens and the therapeutic effect maintained for 15 months

Introduction

To report a case of accidental intralenticular Ozurdex injection in an eye with thicker lens. During the follow-up period of 15 months, the therapeutic effect of intralenticular Ozurdex was maintained.

Case description

Ozurdex was accidently injected into the lens of an eye with uveitis, and the lens thickness was measured to be 5.70 mm. The uveitis was under good control, and no significant development of cataract was observed until 7 months after the intralenticular Ozurdex injection. Then due to the outbreak of COVID-19, follow-up was suspended. Fifteen months after the injection, the patient returned to the doctor. At this time, significant cataract development was observed, whereas uveitis was still under good control. Accordingly, cataract surgery and Ozurdex extraction were performed. Two months after surgery, a mild recurrence of uveitis occurred.

Conclusions

A thicker lens might be an important risk factor for accidental intralenticular Ozurdex injections. However, after intralenticular Ozurdex injection, the development of cataract was slow, and Ozurdex could still have a therapeutic effect on uveitis in this case. Thus, immediate surgery might be unnecessary for certain accidental intralenticular Ozurdex injection cases, and a follow-up strategy could be chosen to maintain the effect of Ozurdex.

Change in axial length after vitrectomy with silicone oil tamponade for rhegmatogenous retinal detachment

Background

We aimed to explore the changes in the axial length and related factors after vitrectomy for rhegmatogenous retinal detachment (RRD).

Methods

This study retrospectively evaluated patients who underwent vitrectomy with silicone oil (SO) tamponade for RRD and subsequent silicone oil removal at our clinic. Using a Zeiss IOLMaster 700, axial length was measured before vitrectomy for RRD and SO removal. The change in axial length (ΔAL) was calculated, and multivariate binary logistic regression analysis was performed to investigate the potential correlation between ΔAL and clinical factors, such as preoperative hypotony, extreme myopia, age, macular involvement, choroidal detachment, operation duration, and operation history.

Results

In total, 213 eyes from 213 patients were included. The mean axial length changed significantly pre- and post-vitrectomy (25.98 ± 2.87 mm and 26.25 ± 3.07 mm, respectively, P < 0.001); the mean ΔAL was 0.37 ± 0.62 mm. Multivariate binary logistic regression analysis showed that preoperative hypotony and extreme myopia were significantly correlated with the ΔAL (P = 0.001 and P = 0.001, respectively). A higher proportion of hypotonic eyes had ΔAL ≥ 0.3 mm (33/76 in hypotony eyes and 32/137 in others; P = 0.003). A higher proportion of extremely myopic eyes also had a ΔAL ≥ 0.3 mm (23/46 in extremely myopic eyes and 42/167 in others; P = 0.002).

Conclusion

For patients with RRD and cataracts, as axial length changed significantly after vitrectomy in those with hypotony or extreme myopia, secondary lOL implantation should be considered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02433-8.

Differences in Axial Length and IOL Power Based on Alternative A-Scan or Fellow-Eye Biometry in Macula-Off Rhegmatogenous Retinal Detachment Eyes

INTRODUCTION

This study was performed to observe the potential refractive prediction error based on alternative A-scan ultrasound and fellow-eye biometry for phacovitrectomy in macula-off rhegmatogenous retinal detachment (RRD) eyes.

METHODS

Phakic macula-off RRD eyes without axial length (AL) measurements obtained using IOLMaster were included. Vitrectomy without lens extraction was performed for RRD repair. Preoperative AL was measured using alternative A-scan ultrasound (AL-US). Postoperative AL was obtained in eyes with silicone oil tamponade (AL-SO) and preoperative fellow-eye biometry (AL-FE) using IOLMaster. Other eyes that faced the same preoperative situation but underwent phacovitrectomy based on fellow-eye biometry were recruited as controls.

RESULTS

AL-US, AL-FE, and AL-SO were 25.39 ± 2.14 mm, 25.85 ± 2.16 mm and 26.08 ± 2.53 mm, respectively. The Bland-Altman agreement among AL-US, AL-FE and AL-SO was good (95.5%, 21/22 of cases were in the LoA). The mean IOL power calculated using AL-US (Power-US), AL-FE (Power-FE) and AL-SO (Power-SO) was 16.81 ± 7.19 D, 14.74 ± 6.95 D and 13.54 ± 8.32 D, respectively. The difference between AL-US and AL-SO was significant (P < 0.05), while that between AL-FE and AL-SO was not (P > 0.05). The difference between Power-US and Power-SO was significant (P < 0.05), while that between Power-FE and Power-SO was not (P > 0.05). Nine eyes underwent phacovitrectomy based on fellow-eye biometry and had a final postoperative myopic shift of 0.64 ± 0.78 D.

CONCLUSIONS

Alternative A-scan ultrasound led to a significant difference in AL and a prediction error in IOL power, while fellow-eye biometry provided similar results to silicone oil-filled eyes after RRD repair.

Development and Verification of an Adjustment Factor for Determining the Axial Length Using Optical Biometry in Silicone Oil-Filled Eyes

The aim of this prospective clinical study was to establish and verify an adaptation for axial length (AL) measurement in silicone oil (SO)-filled pseudophakic eyes with a Scheimpflug and partial coherence interferometry (PCI)-based biometer. The AL was measured with a Pentacam AXL (OCULUS Optikgeräte GmbH, Wetzler, Germany) and IOLMaster 700 (Carl Zeiss Meditec, Jena, Germany). The coefficients of variation (CoV) and the mean systematic difference (95% confidence interval (CI)) between the devices were calculated. After implementing a setting for measuring AL in tamponaded eyes with a Pentacam based on data of 29 eyes, another 12 eyes were examined for verification. The mean AL obtained with the Pentacam was 25.53 ± 1.94 mm (range: 21.70 to 30.76 mm), and with IOLMaster, 24.73 ± 1.97 mm (ranged 20.84 to 29.92 mm), resulting in a mean offset of 0.80 ± 0.08 mm (95% CI: 0.77, 0.83 mm), p < 0.001. The AL values of both devices showed a strong linear correlation (r = 0.999). Verification data confirmed good agreement, with a statistically and clinically non-significant mean difference of 0.02 ± 0.04 (95% CI: −0.01, 0.05) mm, p = 0.134. We implemented a specific adaptation for obtaining reliable AL values in SO-filled eyes with the Pentacam AXL.