Cataract formation following vitreoretinal procedures

Our results of the quadruple procedure in combined vitrectomy

PURPOSE

To reveal the outcomes of combined phacovitrectomy and supplementary scleral buckling (SB) surgery in patients with inferior break retinal detachment (RD) and proliferative vitreoretinopathy (PVR) ≥ Stage-C.

METHODS

In this retrospective study, 22 eyes of 22 patients who underwent surgery in Bozyaka Training and Research Hospital between 2018 and 2020 were included. The demographic data, follow-up duration, preoperative & postoperative best-corrected visual acuity (BCVA) (Snellen), intraocular pressure (IOP), final anatomic status, and the recurrence rate of RD were recorded from the files of patients.

RESULTS

The mean age of the patients was 56.9 ± 15.2 years, and follow-up duration was 16.6 ± 10.2 months. The internal tamponade was silicone oil (SO) in 16 patients (72.7%), and perfluoropropane (C3F8) in 6 patients (27.2%). The BCVA was improved from 0.0065 ± 0.014 to 0.26 ± 0.17 after surgery (p:0,0001), and IOP changed from 12.3 ± 2.5 mmHg to 15.3 ± 2.4 mmHg. During follow-up period, the recurrent RD was only found in one patient (4.50%) and following to second surgery, anatomical success was achieved in all of the patients (100%) in final visit.

CONCLUSION

The combined phacovitrectomy and SB is an effective and reliable surgical method in patients with inferior quadrant RD and advanced stage PVR.

Effect of femtosecond laser-assisted cataract surgery for cataracts after pars plana vitrectomy: a prospective randomized controlled study

OBJECTIVE

To compare the efficacy of femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification surgery (CPS) in treating postvitrectomy cataracts.

METHODS

Prospective randomized controlled study. Patients who underwent cataract surgery after pars plana vitrectomy (PPV) were randomly divided into the FLACS group and the CPS group. Preoperative data of all patients were collected to compare intraoperative complications, average phacoemulsification energy (AVE), effective phacoemulsification time (EPT), postoperative intraocular pressure, corneal endothelial cell density (ECD), and best corrected visual acuity (BCVA).

RESULTS

A total of 92 eyes were included in the analysis, with 47 eyes in the FLACS group and 45 eyes in the CPS group. The intraoperative AVEs and EPTs in the FLACS group were both lower than those in the CPS group (P < 0.05). In the FLACS group, incomplete prechopping and incomplete capsulorhexis occurred in 3 eyes (3/47, 6.38%), and incomplete lens dislocation occurred in 1 eye (1/47, 2.13%). In the CPS group, incomplete lens dislocation occurred in 2 eyes (2/45, 4.44%), and anterior capsule tears occurred in 1 eye (1/45, 2.22%). There was no statistically significant difference in intraoperative complications between the two groups (P > 0.05). Postoperatively, intraocular pressure (IOP) was lower in both groups than preoperatively, and there was no statistically significant difference in intraocular pressure between the two groups at three months postsurgery (P > 0.05). Three months postoperatively, the ECD in the FLACS group was greater than that in the CPS group, with less average endothelial cell loss (ECL) than that in the CPS group (P < 0.01). The BCVA in both groups improved to varying degrees compared with the preoperative values, with the FLACS group performing better than the CPS group on the first postoperative day (P < 0.05). There was no statistically significant difference between the two groups at one week, one month, or three months postoperatively (all P > 0.05).

CONCLUSION

FLACS is safe and effective for treating post-PPV cataracts and, compared with CPS, facilitates early postoperative recovery with no difference in final visual acuity. Residual silicone oil in the anterior chamber post-PPV may lead to certain specific outcomes for FLACS. Although it may not affect surgical results, it is still noteworthy.

Challenges and outcomes of cataract surgery after vitrectomy

PURPOSE OF REVIEW

This review examines the challenges and outcomes of cataract surgery after pars plana vitrectomy (PPV), focusing on surgical techniques, timing, and complication management.

RECENT FINDINGS

Cataract formation remains the primary complication post-PPV, affecting approximately 80-100% of patients within two years. Nuclear sclerotic cataracts are most common, occurring in 60-100% of patients over 50, followed by posterior subcapsular cataracts (4-34%), which primarily affect younger and diabetic patients. PPV disrupts the normal oxygen gradient in the vitreous, resulting in a more uniform oxygen distribution and accelerating cataract formation.Post-PPV eyes present unique surgical challenges due to anatomical alterations, including zonular instability and capsular changes characterized by increased fragility, the potential for tears, and altered elasticity. Newer intraocular lens power calculations show promise, but unexpected refractive outcomes may occur. The choice between combined phacovitrectomy and sequential surgeries remains debated, with patient-specific factors guiding the approach. Visual outcomes vary depending on preexisting vitreoretinal pathologies and baseline vision before PPV. Further randomized controlled trials are needed to establish treatment guidelines and improve predictive models.

SUMMARY

Post-PPV cataract surgery presents unique challenges, including anatomical alterations and an increased risk of capsular complications. These necessitate careful consideration of the surgical approach and highlight the need for further research to optimize outcomes and establish treatment guidelines.

In Vivo Assessment of an Antioxidant Hydrogel Vitreous Substitute

The vitreous humor undergoes liquefaction with age, resulting in complications that may require a vitrectomy, or surgical removal of the vitreous from the eye. Silicone oil, a common vitreous substitute, lacks properties similar to the natural vitreous. In particular, it lacks antioxidants that may be necessary to reduce oxidative stress in the eye. The purpose of this study was to evaluate antioxidant-loaded hydrogel vitreous substitutes in a pilot in vivo study. Ascorbic acid and glutathione were loaded into synthesized PEGDA hydrogels. Following vitrectomy, experimental antioxidant hydrogels or silicone oil were injected into one eye of rabbits, while the other eye served as untreated or sham control. Ophthalmic assessments, including electroretinography, were performed. Levels of glutathione and ascorbic acid were higher in the eyes treated with the antioxidant-loaded hydrogel vitreous substitute, although this was not found to be significant after 28 days. There were no statistically significant differences between groups with respect to clinical examination, and ocular health scores, electroretinograms, and histology were normal. These results indicate minimal concerns for the hydrogel formulation or high levels of antioxidants. Future research will assess the capability of vitreous substitutes to prolong antioxidant release, with the goal of minimizing cataract after vitrectomy.

Phacovitrectomy vs. consecutive vitrectomy for idiopathic macular holes: short and long-term outcomes and OCT image quality assessment

PURPOSE

To compare short- and long-term anatomical, functional, and refractive outcomes between combined phacovitrectomy (PVS) and consecutive vitrectomy (CVS) for idiopathic macular holes (MHs). Also, to evaluate the role of preoperative optical coherence tomography (OCT) image quality in guiding surgical selection.

METHODS

This retrospective study analyzed 183 phakic MH eyes operated between 2012 and 23, with patients divided into PVS and CVS groups. Demographic and ocular data, MH features, visual acuity (VA), refraction changes and postoperative outcomes, and follow-up details were collected. Pre- and post-operative OCT scans were evaluated for MH characteristics, OCT image quality, and surgical outcomes at short-term (≤ 3 months) and long-term (≥ 5 years) intervals.

RESULTS

The study included 144 eyes in PVS group and 39 in CVS group. Median follow-up duration was 16 months for PVS group and 72 months for CVS group (p < 0.001). Both groups showed significant VA improvements and comparable MH closure rates at short-term follow-up. However, CVS group had significantly better postoperative VA at short-term (p = 0.001) and long-term (p = 0.017) intervals. The preoperative OCT quality index did not significantly differ between groups and was ineffective in assessing cataract grade or guiding surgical decisions. Both groups experienced a myopic refractive shift, with a higher magnitude in the PVS group (p = 0.04). Postoperative complications were similar between the groups.

CONCLUSION

CVS achieves better long-term VA than PVS following MH repair, despite similar anatomical outcomes. Preoperative OCT quality index is not effective for guiding surgical decisions, and careful refractive planning is essential, especially for PVS patients, to address postoperative myopic shifts.

CLINICAL TRIAL REGISTRATION NUMBER

Not applicable.

Minimizing Oxidative Stress in the Lens: Alternative Measures for Elevating Glutathione in the Lens to Protect against Cataract

Oxidative stress plays a major role in the formation of the cataract that is the result of advancing age, diabetes or which follows vitrectomy surgery. Glutathione (GSH) is the principal antioxidant in the lens, and so supplementation with GSH would seem like an intuitive strategy to counteract oxidative stress there. However, the delivery of glutathione to the lens is fraught with difficulties, including the limited bioavailability of GSH caused by its rapid degradation, anatomical barriers of the anterior eye that result in insufficient delivery of GSH to the lens, and intracellular barriers within the lens that limit delivery of GSH to its different regions. Hence, more attention should be focused on alternative methods by which to enhance GSH levels in the lens. In this review, we focus on the following three strategies, which utilize the natural molecular machinery of the lens to enhance GSH and/or antioxidant potential in its different regions: the NRF2 pathway, which regulates the transcription of genes involved in GSH homeostasis; the use of lipid permeable cysteine-based analogues to increase the availability of cysteine for GSH synthesis; and the upregulation of the lens's internal microcirculation system, which is a circulating current of Na+ ions that drives water transport in the lens and with it the potential delivery of cysteine or GSH. The first two strategies have the potential to restore GSH levels in the epithelium and cortex, while the ability to harness the lens's internal microcirculation system offers the exciting potential to deliver and elevate antioxidant levels in its nucleus. This is an important distinction, as the damage phenotypes for age-related (nuclear) and diabetic (cortical) cataract indicate that antioxidant delivery must be targeted to different regions of the lens in order to alleviate oxidative stress. Given our increasing aging and diabetic populations it has become increasingly important to consider how the natural machinery of the lens can be utilized to restore GSH levels in its different regions and to afford protection from cataract.

Assessment of Zonular Integrity in Phakic Eyes Following Pars Plana Vitrectomy Using Ultrasound Biomicroscopy: A Prospective Paired Eye Comparative Study

PURPOSE

To assess zonular integrity in phakic patients post vitrectomy using ultrasound biomicroscopy (UBM).

DESIGN

Prospective, comparative, nonrandomized, double-masked, paired eye study.

METHODS

We used ultrasound biomicroscopy (UBM) to evaluate phakic patients with a history of unilateral pars-plana vitrectomy.

INCLUSION CRITERIA

(1) phakic patients with history of pars plana vitrectomy in one eye as the only procedure; (2) normal unoperated fellow eye; and (3) complete gas or air resolution from the vitreous cavity at the time of UBM assessment.

EXCLUSION CRITERIA

(1) monocular patients; (2) history of intraoperative lenticular trauma; (3) the use of silicone oil tamponade; (4) history of trauma or pseudoexfoliation in either eye; (5) history of other ocular conditions that can affect the integrity of zonules, such as uveitis or ectopia lentis; (6) eyes with extreme myopia or long axial length (> -8.00 D or >30.0 mm); (7) history of intravitreal injection in either eye; (8) age <18 years.

TECHNIQUE

A high-frequency (50 MHz) UBM device was used by a masked technician to obtain radial section images from zonular bundles at 8 different clock positions. Image quality was assessed in real time, captured, and saved. Two experienced masked observers (H.C. and C.B.) then assessed the quality of the images and graded the zonular findings. Only patients with adequate studies have been included. A unique grading system that was specifically devised for this study was used as the following: (0) clear, well-defined zonule(s); (1) uneven, disrupted zonules or stretched zonules; and (2) extensive loss of zonules. Each clock hour was graded according to this system and the total score was then calculated for each eye. In the primary outcome, 2 main groups were analyzed: vitrectomized eyes and healthy contralateral nonvitrectomized eyes. The mean total UBM score (TUS) from each group was compared and analyzed.

RESULTS

Thirty-five patients were recruited into this study. Eleven patients were male and 24 were female. The mean age was 66.3 years. Thirty patients had vitrectomy for vitreomacular interface disorders (either macular hole or epiretinal membrane), 1 patient had vitreous hemorrhage and the remaining 4 patients had rhegmatogenous retinal detachments. With regard to tamponade agents, SF6 was used in 21 (60%) patients, air in 9 (26%) patients, and C3F8 in 5 (14%) patients. The mean TUS in the vitrectomized eyes was 2.28 (SD 1.83) vs 2.24 (SD 1.77) in the nonvitrectomized eyes (P = .9531). Overall, in the comparative analysis of mean scores based on 2 graders' assessments for each clock position in vitrectomized and nonvitrectomized eyes, there were no significant differences noted between the groups.

CONCLUSION

This study found no evidence for a difference in the mean total UBM score in eyes following vitrectomy when compared to their contralateral healthy, nonvitrectomized eyes. This likely indicates that vitrectomy may not affect the integrity of zonules in phakic patients, at least for patients with vitreomacular interface disorders undergoing uncomplicated surgery.

Ascorbic acid export from human donor lenses: Is the lens a source of ascorbic acid in the ocular humors?

In previous work, we have shown that the lens acts a reservoir of the antioxidant glutathione (GSH), capable of exporting this antioxidant into the ocular humors and potentially protecting the tissues of the eye that interface with these humors from oxidative stress. In this study, we have extended this work by examining whether the lens acts as a source of ascorbic acid (AsA) to maintain the high levels of AsA known to be present in the ocular humors either by the direct export of AsA into the humors and/or by functioning as a recycling site for AsA, via the direct uptake of oxidised ascorbate (DHA) from the humors, its regeneration to AsA in the lens and then its subsequent export back into the humors. To test this, human lenses of varying ages were cultured for 1 h under hypoxic conditions and AsA/DHA levels measured in the media and in the lens. Human lenses were also cultured in compartmentalised chambers to determine whether efflux of AsA/DHA occurs at the anterior or posterior surface. Immunohistochemistry was performed on human donor lenses and sections labelled with antibodies against GLUT1, a putative DHA uptake transporter. Vitreous humor was collected from patients undergoing vitrectomy who either had a natural clear lens, an artificial intraocular implant (IOL) or a cataractous lens, and AsA/DHA and GSH and oxidised GSH (GSSG) measured. We found that cultured human donor lenses released both AsA and DHA into the media. Culturing of lenses in a compartmentalised chamber revealed that AsA and DHA efflux occurs at both surfaces, with relatively equal amounts of AsA and DHA released from each surface. The posterior surface of the lens was shown to express the GLUT1 transporter. Analysis of vitreous samples from patients undergoing vitrectomy revealed that vitreous GSH and AsA levels were similar between the natural lens group, IOL and cataractous lens group. Taken together, while human donor lenses were shown to export AsA and DHA into the surrounding media, the amount of AsA and DHA released from donor lenses was low and not sufficient to sustain the high levels of total AsA normally present in the humors. This suggests that although the lens is not the main source for maintaining high levels of AsA in the ocular humors, the lens may help to support local AsA levels close to the lens.

Clinical features of retinal detachment treated with segmental scleral buckling

PURPOSE

Our study aims to evaluate the surgical outcomes and clinical features of retinal detachment (RD) cases treated with segmental scleral buckling (SB), elucidating the role of segmental SB as a vital option in specific situations during the current era.

METHODS

We retrospectively reviewed 128 eyes with primary rhegmatogenous RD that underwent segmental scleral buckling between November 2008 and December 2020. Clinical features and success rates were recorded and analyzed.

RESULTS

A total of 128 eyes were included. The patient's ages ranged from 12 to 72 years, with a median age of 45. Most of the eyes were phakic (97%). Regarding the type of break, 47% were holes, and flap tears were found in 68 cases (53%). The break locations were superior-temporal (54%), inferior-temporal (31%), superior-nasal (9.5%), and inferior-nasal (5.5%). The length of the SB applied ranged from 3.5 to 8.0 clock hours, with a median of 6.0. Primary success was achieved in 121 eyes, and recurrence occurred in 7 eyes. All recurrent RD cases reattached after undergoing secondary VT. The causes of failure included 2 break reopens, 1 missed break, and 4 eyes with proliferative vitreoretinopathy. The single-surgery anatomic success (SSAS) rate for segmental SB was 94.5%. The final success rate was 100%.

CONCLUSIONS

For phakic, low complexity retinal detachment in our study, segmental scleral buckling emerges as a surgical option with a high primary success rate and a lower incidence of complications.

Outcomes of Scleral Buckling After Failed Pneumatic Retinopexy

Purpose: To assess the visual and anatomic outcomes of eyes that had secondary scleral buckle (SB) surgery after unsuccessful pneumatic retinopexy (PR) for rhegmatogenous retinal detachment (RRD). Methods: A retrospective study, performed over a 12-year period, comprised patients who had secondary SB procedures after failed primary PR. Clinical parameters (eg, best-corrected visual acuity [BCVA], lens status, macula status, details of RRD and subretinal fluid) were assessed at presentation, before additional procedures, and at follow-up (6 months, 1 year, and last visit). Statistical comparisons were made using Brown-Forsythe and Welch analysis-of-variance tests, with significance levels set at P < .05. Results: Fifty-four eyes with adequate follow-up were included. Forty-four (81.5%) of 54 eyes had successful retinal reattachment with secondary SB alone. The remaining eyes had subsequent pars plana vitrectomy (PPV). Patients presenting with macula-on RRD who had successful secondary SB had no statistically significant change in BCVA from baseline (mean final, 0.23 ± 0.25 logMAR [Snellen 20/34]; P = .999). There was a statistically significant improvement in BCVA in patients presenting with macula-off RRD who had successful secondary SB (mean final, 0.32 ± 0.36 logMAR [20/42]; P < .001 and mean change, -1.06 ± 0.85 logMAR). Ten patients presenting with macula-off RRD who had failed secondary SB had a significant improvement in the final BCVA (mean final, 0.22 ± 0.28 logMAR [20/33]; P = .044), despite the need for an additional PPV to achieve reattachment. Conclusions: Secondary SB remains a good option for RRD repair after unsuccessful PR and may avoid the need for PPV.

Cataract progression after primary pars plana vitrectomy for uncomplicated rhegmatogenous retinal detachments in young adults

BACKGROUND

Scleral buckling is typically implemented to repair rhegmatogenous retinal detachments (RRD) in young patients. Therefore, there is limited data on post-pars plana vitrectomy (PPV) cataract formation in this cohort. We report the rates and risk factors of cataract progression after PPV for RRD repair in young eyes.

METHODS

Retrospective single-center cohort study. Medical records of patients between the ages of 15 to 45 undergoing PPV for uncomplicated RRD between 2014 and 2020 were reviewed.

RESULTS

Twenty-eight eyes from 26 patients met inclusion criteria. Cataracts developed in 20/28 (71%) eyes after PPV. After PPV, nuclear sclerotic cataract (NSC) rates were higher in patients above 35 (65%) compared to below 35 years (18%) (p = 0.024). Cataracts developed more frequently after macula-off RRDs (88%) compared to macula-on RRDs (50%) (p = 0.044) with NSC more common in macula-off detachments (p = 0.020). At postoperative month 2, all eyes with C3F8 gas developed cataracts compared to 59% of eyes with no gas (p = 0.040).

CONCLUSIONS

Cataract formation was common and frequent after PPV. After PPV, young eyes and macula-on detachments developed cataracts less frequently than older eyes and macula-off detachments. If appropriate, a shorter acting gas tamponade should be considered in young eyes to minimize cataract formation.

Use of 30 gauge needle to prevent hypotony during silicone oil removal

Silicone oil (SO) is used as an intraocular tamponade after complex vitreoretinal surgeries because of its properties such as transparency, inertness, high surface tension, and interfacial tension with water. The only disadvantage of SO tamponade is the need for a second surgery for its removal. However, there is a risk of ocular hypotony soon after the removal of the infusion cannula, especially in retinal vascular conditions, such as diabetic retinopathy. We hereby present a silicone oil removal (SOR) technique using a 30 G needle that prevents intraocular hypotony during SOR.

Modification of the Suprachoroidal Buckling Technique for the Treatment of Rhegmatogenous Retinal Detachment

PURPOSE

To describe modification of the suprachoroidal buckling technique for the treatment of rhegmatogenous retinal detachment (RRD), which may improve the safety profile.

METHODS

A single-surgeon foot-pedal-controlled automated suprachoroidal injection (SCI) of sodium hyaluronate 1%, namely ProVisc (Alcon Laboratories, Fort Worth, TX) was used for the treatment of RRD. MicroDose Injection Kit (MedOne Surgical, Sarasota, FL) including a connector and a 1-mL syringe, designed for subretinal injection, was used to adapt Constellation Vision System (Alcon Laboratories) console for SCI of ProVisc from the 1-mL syringe.

RESULTS

This approach enables better surgeon control during SCI. Three highly myopic eyes of three patients with primary macula-on RRD and single superior peripheral retinal break were treated. Complete retinal reattachment was achieved in all eyes without complications.

CONCLUSION

Injecting ProVisc under foot-pedal control provides a more precise and potentially safer suprachoroidal buckling technique compared with the manual technique with more variable injection speed and pressure.

Enhancing Scleral Buckling Surgery Using an Illuminated Scleral Depressor

PURPOSE

To report a technique for scleral buckling surgery under the operating microscope with wide-field viewing.

METHODS

The identification and reliable marking of retinal breaks is one of the key steps for successful surgery in scleral buckling. For sufficient visualization of retinal breaks, some kind of indentation and illumination is necessary. In this technique, one instrument (Visible Periphery illuminated scleral indentor; Oertli Instrumente AG, Switzerland) combines scleral depression, illumination, and color marking (using a surgical marking pen) of the corresponding sclera above the retinal break.

RESULTS

The illuminated scleral depressor enables the surgeon to safely and precisely mark the retinal break while stabilizing and rotating the eye with the other hand. This technique simplifies scleral buckling surgery by improving the handling and visualization of marking retinal breaks at the corresponding scleral. Neither intraoperative indirect ophthalmoscopy nor sclerotomies for chandelier light systems or any intraocular instrument are necessary.

CONCLUSION

The illuminated scleral depressor facilitates scleral buckling surgery in a convenient way for easy and precise scleral marking of the retinal breaks even in challenging situations and positions of retinal breaks under the operating microscope with wide-field viewing. Indirect ophthalmology or other illumination sources are no longer needed.

Pars Plana Vitrectomy Alone or Combined with Phacoemulsification to Treat Rhegmatogenous Retinal Detachment: A Systematic Review of the Recent Literature

Pars plana vitrectomy is today a common first-line procedure for treatment of rhegmatogenous retinal detachment (RRD). Removal or preservation of the natural lens at the time of vitrectomy is associated with both advantages and disadvantages. The combination of cataract extraction (i.e., phacoemulsification) with pars plana vitrectomy (PPVc) enhances visualization of the peripheral retina and the surgical management of the vitreous base. However, PPVc prolongs the surgical time and is associated with iatrogenic loss of the accommodation function in younger patients, possible postoperative anisometropia, and unexpected refractive results. Performance of pars plana vitrectomy alone (PPVa) requires good technical skills to minimize the risk of lens damage, and quickens cataract development. We retrieved all recent papers that directly compared PPVc and PPVa using parameters that we consider essential when choosing between the two procedures (the success rate of anatomical RRD repair, postoperative refractive error, intra- and postoperative complications, and costs). PPVa and PPVc were generally comparable in terms of RRD anatomical repair. PPVc was associated with fewer intraoperative, but more postoperative, complications. Macula-off RRD PPVc treatment was often associated with undesirable myopic refractive error. PPVa followed by phacoemulsification was the most expensive procedure.

Impact of prior pars plana vitrectomy on development of cystoid macular edema after uneventful cataract surgery

PURPOSE

To investigate whether a history of prior pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) predisposes to the development of pseudophakic cystoid macular edema (CME).

SETTING

New York Eye and Ear Infirmary of Mount Sinai, New York, New York.

DESIGN

Retrospective cohort study.

METHODS

Records of 365 subjects who underwent PPV for RRD and subsequent cataract surgery between 2017 and 2020 were reviewed. Patients with a history of diabetic retinopathy, inflammatory retinal vascular disease, uveitis, advanced age-related macular degeneration, intraocular infection, myopic maculopathy, or significant intraoperative complications precluding posterior chamber intraocular lens placement were excluded. Age-matched subjects who underwent routine cataract surgery served as controls. Clinical data and macular optical coherence tomography (OCT) findings up to 4 years postoperatively were obtained.

RESULTS

54 eyes underwent uneventful cataract surgery by phacoemulsification and had a history of PPV with gas tamponade. 55 eyes underwent uneventful cataract surgery only. The average follow-up time after cataract surgery was 39.1 months. In eyes with a history of PPV, the incidence of OCT-detected CME was 27.8% (15/54) compared with 3.8% (2/55) in the control group ( P < .001) and the incidence of clinically significant CME was 18.5% (10/54) compared with 1.8% (1/55) in the control group ( P = .004). 80% (12/15) of CME cases were treated with topical therapy, and none required intravitreal injection.

CONCLUSIONS

Prior PPV for RRD is associated with an increased incidence of pseudophakic CME after uneventful cataract surgery. Prophylactic or prolonged postoperative anti-inflammatory topical therapy may be prudent to consider in these patients.

Outcomes and complications of primary rhegmatogenous retinal detachment repair with pars plana vitrectomy in young adults

BACKGROUND

Scleral buckling has been the standard for rhegmatogenous retinal detachment repair in young patients given the typical lack of posterior vitreous detachment, phakic status, and lower risk of proliferative vitreoretinopathy. In older patients, pars plana vitrectomy alone is typically used for rhegmatogenous retinal detachment repair. We report the outcomes and complications of pars plana vitrectomy for rhegmatogenous retinal detachment in young eyes.

METHODS

Retrospective, single-center cohort study. Medical records of patients between 15 to 45 years of age undergoing primary pars plana vitrectomy for rhegmatogenous retinal detachment repair between 2010 and 2020 were carefully reviewed. All analyses were performed using the Kruskal-Wallis tests for numeric covariates between age groups.

RESULTS

Eyes were stratified by age: 15-24 (group 1, n = 10), 25-34 (group 2, n = 14), and 35-45 (group 3, n = 38). The average number of surgeries were 1.9, 1.4, and 1.1 in groups 1, 2, and 3, respectively (p = 0.004). Single surgery success rates were 50%, 64%, and 92% in groups 1, 2 and 3, respectively (p = 0.005). Final reattachment rates were 80%, 93%, 100% in groups 1, 2, and 3, respectively (p = 0.568). Proliferative vitreoretinopathy developed in 50%, 7%, and 8% of eyes in groups 1, 2, and 3, respectively (p < 0.001).

CONCLUSION

While the final reattachment rates were excellent in all groups, the higher rates of proliferative vitreoretinopathy and lower single surgery success rate in younger patients may suggest that primary pars plana vitrectomy may not be the optimal repair method in these age groups.

Rhegmatogenous retinal detachment surgery: A review

Rhegmatogenous retinal detachment (RRD) is a serious surgical condition with significant ocular morbidity if not managed properly. Once untreatable, approaches to the repair of RRD have greatly evolved over the years, leading to outstanding primary surgical success rates. The management of RRD is often a topic of great debate. Scleral buckling, vitrectomy and pneumatic retinopexy have been used successfully for the treatment of RRD. Several factors may affect surgical success and dictate a surgeon's preference for the technique employed. In this review, we provide an overview and supporting literature on the options for RRD repair and their respective preoperative and postoperative considerations in order to guide surgical management.

Cataract progression following lens-sparing pars plana vitrectomy for rhegmatogenous retinal detachment

Lens-sparing pars plana vitrectomy (PPV) is often followed by cataract development. However, there have been few prospective studies evaluating the timing of cataract progression and potential associated factors. This was an observational study conducted at the Ophthalmology Unit of the University Hospital of Parma (Parma, Italy). Patients presenting with rhegmatogenous retinal detachment (RRD), who underwent PPV with preservation of the lens, were examined according to a scheduled follow-up (3, 6 and 12 months after PPV) and then preoperatively when cataract extraction surgery (CES) was indicated, or at the end of the study follow-up period (May 2021). The primary outcome was the interval between PPV and CES indication (based on predefined refractive criteria). A total of 36 eyes of 36 patients (mean age: 52 ± 10 years) were included in the study. Nineteen eyes (53%) were indicated for CES a median of 14.5 months (IQR: 12.0-24.8) after PPV. The nuclear and posterior subcapsular forms of cataract progressed significantly starting at 6 months after PPV. Older age at the time of PPV, silicone oil tamponade and RRD without macular involvement were significantly and independently associated with an earlier indication for CES. Patient age and the use of silicone oil tamponade must be taken into consideration when evaluating the risk of cataract development after PPV.

Impact of Race and Ethnicity on Presentation and Surgical Outcomes of Idiopathic Macular Holes

There is limited data on the presentation and surgical outcomes of idiopathic macular holes (IMH) for different ethnic and racial groups. Recognition of distinct, clinically-relevant patient subgroups may provide opportunities to identify specific unmet needs including possible barriers to optimal healthcare delivery. Medical records of patients who underwent surgery for IMH (between 2016 and 2022) at a large, urban retina practice were reviewed and self-reported ethnicity (Hispanic and non-Hispanic) and race (Asian, Black, White, and Other) were captured. The primary variables included (1) mean minimum linear diameter (MLD) at presentation and (2) surgical outcome (IMH closure status). Overall, mean MLD for all study eyes (515) was 366.1 μm, and surgical success was achieved in 489 (95.0%) eyes. Hispanic eyes presented with larger mean MLD (p = 0.002) compared to non-Hispanic eyes. Asian, Black, and Other eyes presented with larger mean MLD (p = 0.033, p < 0.001, p < 0.001) when compared to White eyes. The presentation of IMH varied in severity among different ethnic and racial groups. Hispanic patients were found to have worse preoperative visual acuity (VA), longer time to surgery, and larger mean MLD and BD compared to non-Hispanic participants. Black and Other patients were found to have worse VA, time to surgery, and larger mean MLD and BD when compared to White participants.

Refractive Outcomes of Combined Cataract Surgery and Vitrectomy Compared to Cataract Surgery Alone

PURPOSE

The aim of the study was to evaluate the refractive outcomes of combined cataract surgery and vitrectomy compared to cataract surgery alone.

METHODS

This retrospective chart review study included two groups: (1) combined surgery in 103 eyes (101 patients) who underwent cataract surgery with posterior chamber intraocular lens (PCIOL) placement by a single cataract surgeon and vitrectomy by a single vitreoretinal surgeon at the same surgical setting; (2) cataract surgery alone by the same surgeon in 107 eyes (84 patients). Refractive outcomes and complications between the combined and cataract surgery alone group were compared. The predicted refractive error was compared to postoperative refractive outcomes in both groups, surgically induced astigmatism (SIA), intraoperative or postoperative complications of either cataract surgery or vitrectomy, and cystoid macular edema.

RESULTS

There was no statistically significant difference between predicted and actual postoperative refractive outcomes between the combined and cataract surgery alone groups (within ±0.5 diopters [D], p = 0.099; within ±1.0 D, p = 0.721). There was no difference in SIA refractive outcomes between the two groups (p = 0.509). The use of intraoperative gas for retina tamponade did not significantly affect postoperative refractive outcomes. Both cataract surgery and vitrectomy were successfully performed without unexpected complications from either procedure affecting the other.

DISCUSSION/CONCLUSION

Combined cataract surgery and vitrectomy allows excellent refractive outcomes equal to cataract surgery alone, allowing each procedure to be performed independently by separate anterior and posterior segment surgeons. Combined procedures can be performed in eyes with a variety of retinal indications and can include fluid-gas exchange with minimal risk of PCIOL malposition or change in targeted refraction.

The Postvitrectomy Cataract

To review the recent literature regarding risk factors for cataract formation after vitrectomy, the challenges and management strategies for anterior segment surgeons when facing post-vitrectomy cataract surgery, and the visual outcomes of patients undergoing post-vitrectomy cataract surgery. Cataract surgery after vitrectomy can be safely performed to significantly improve the visual outcome in most post-vitrectomy patients, although final visual acuity is primarily limited by the patient’s underlying vitreoretinal pathology.

Predicting speed of progression of lens opacification after pars plana vitrectomy with silicone oil

Purpose

An increasing number of posterior segment disorders is routinely managed with pars plana vitrectomy (PPV). In older, phakic patients cataract formation is expected within the first two years after surgery. For younger patients its progression is individually fluctuating. This study uses an objective quantitative measurement for lens-status-monitoring after PPV with silicone oil to derive predictions for progression and severity of post-operative lens opacification evaluated in patients with rhegmatogenous retinal detachment (RRD).

Methods

Data acquisition was performed prospectively between March 2018 and March 2021. PentacamHR® Nucleus Staging mode (PNS) was used to objectively gather data about nuclear cataracts after PPV at different time points. Data was grouped into training and test sets for a mathematical prediction model. Via backward variable selection method a mathematical formula was set up by means of which predictions about lens densitometry (LD) can be calculated.

Results

20 males [58.8%] and 14 females [41.2%] matched the inclusion criteria (mean age 50.6 years [23–75; ±12.3]). Average follow-up was 8.1 months (3,4–17.4; ±3.4). Mean baseline LD of the treated and fellow eye before surgery was 11.1% (7.7%-17.6%; ±2.0) and 11.2% (7.7%-14.8%; ±1.5), respectively. Predicted LD values by the model for five pre-selected patients closely match the observed data with an average deviation of 1.06%.

Conclusions

Using an objective parameter like LD delivered by the PentacamHR® PNS mode additionally to the patient’s age allows us to make an individual prediction for any time after PPV with silicone oil due to RRD for all ages. The accuracy of the model was stronger influenced by baseline LD as cofactor in the equation than patient’s age. The application for the prediction lens opacification [which can be accessed for free under the following link (https://statisticarium.com/apps/sample-apps/LensDensityOil/)] can help vitreoretinal surgeons for patient consultation on the possibility to combine PPV with cataract surgery.

Rhegmatogenous retinal detachment repair-does age, sex, and lens status make a difference?

PURPOSE

To analyze the correlation between lens status, age, and sex in the epidemiology and success rates of rhegmatogenous retinal detachment (RRD) surgery.

METHODS

The files of all consecutive patients undergoing vitreoretinal surgery for uncomplicated RRD between Jan 2005 und Dec 2020 were retrospectively reviewed. Successful outcome was defined as no retinal redetachment occurring within 3 months after surgery.

RESULTS

5502 eyes with uncomplicated primary RRD were included. Mean age of the patients was 61.1 years (± 13.6 SD). In the age group over 40 years, a male predominance was found. The percentage of pseudophakic RRD increased from 25 to 40% during the 15 years observation period. In the age group 50 to 69 years, patients with pseudophakic detachments were male in 786 out of 1079 cases (72.9%). In the same age group, 1285 of 2110 (60.9%) patients with phakic RRD were male. Overall, primary success rate after one procedure was 91.2% (5018 of 5502). In the phakic eyes, the primary success rate was higher in those eyes that underwent combined phacovitrectomy (93.0%), compared to those without simultaneous cataract surgery (88.7%; p = 0.002).

CONCLUSION

The ratio of male and female patients with RRD varies between age groups. The proportion of pseudophakic RRD has increased within 15 years. The male predominance in RRD is stronger in pseudophakic than in phakic eyes. In phakic eyes with RRD, a combined phacovitrectomy yielded better anatomical results.

Return to the Operating Room After Repair of Rhegmatogenous Retinal Detachment

Purpose

To report the rate of all-cause returns to the operating room (OR) after surgery for rhegmatogenous retinal detachment (RRD).

Patients and Methods

This was a retrospective consecutive case series; 1278 eyes underwent RRD repair from 1/1/2014 to 12/31/2016 at a tertiary care center. A total of 507 eyes returned to the OR. Surgical indication, procedure, number of reoperations, and final vision were recorded.

Results

At least one secondary procedure was performed in 24.9% at 6 months, 34.7% at 1 year, and 39.7% as of last follow-up. The most common indications for reoperation were cataract (43.9%) and recurrent RRD (12.8%). Cornea, glaucoma, and oculoplastic issues were rare (each <1.1%). There was no association between final visual outcome and number of reoperations (p > 0.05). SB/PPV had the highest rate of return to OR (p < 0.001) but lowest rate of recurrent RRD (p = 0.007).

Conclusion

To our knowledge, there are no other large studies that examine all-cause returns to the OR after primary RRD repair. This study provides important risk-benefit and prognostic information to patients undergoing RRD repair.

An objective evaluation of lens transparency after vitrectomy surgery with different intravitreal tamponades

PURPOSE

To evaluate and compare the effects of different intraocular tamponade agents on lens density after vitrectomy.

METHODS

The participating patients were divided into four groups according to the tamponade agent used: a sulfur hexafluoride (SF6) group, a perfluoropropane (C3F8) group, a silicone oil group, and a no tamponade group. Lens density measurements were performed preoperatively and two weeks, one month, and three months postoperatively using a Pentacam HR device with a Scheimpflug camera. The postoperative values were compared with the preoperative baseline values, also the values were compared between the four groups.

RESULTS

The study included 82 eyes (82 patients). In the SF6 group, lens density significantly increased in all zones two weeks and one and three months postoperatively (all P < .05). In the C3F8 group, lens density significantly increased in all zones three months postoperatively (all P < .01). In the silicone oil group, the zone 1, zone 2, and average lens density (ALD) value significantly increased one and three months postoperatively (all P < .05). In the no tamponade group, the zone 1, zone 2, and ALD values significantly increased three months postoperatively (all P < .05). There were no significant differences between the four groups in any zone either preoperatively or postoperatively (all P > .05).

CONCLUSIONS

Although increases in lens density were observed earlier in the tamponade groups than in the no tamponade group, between the groups over the follow-up period were no differences. We need the development of new surgical methods and materials to prevent post-vitrectomy lens damage in the future.

Outcomes of Combined Scleral Buckling Plus Pneumatic Retinopexy Vs. Scleral Buckling for Primary Rhegmatogenous Retinal Detachment

PURPOSE

To evaluate the outcomes and complications of scleral buckle surgery alone or combined with pneumatic retinopexy (pneumatic buckle) for the treatment of primary rhegmatogenous retinal detachment.

DESIGN

Retrospective chart review.

PARTICIPANTS

Two hundred thirteen patients with rhegmatogenous retinal detachment of whom 101 underwent primary scleral buckle surgery at Rabin Medical Center in 2005-2015 (SB group) and 112 underwent pneumatic buckle surgery at Royal Alexandra Hospital in 2013-2015 (PB group).

METHODS

All patients were followed for ≥12 months. Data on clinical and surgical parameters, outcome, and complications were collected from the medical files.

MAIN OUTCOME MEASURES

Best corrected visual acuity and anatomical outcomes.

RESULTS

At 12 months, average best corrected visual acuity was 0.3 logMar in the SB group and 0.42 logMar in the PB group (P < 0.05). Rates of anatomical reattachment were high and similar in the two groups (99% and 97%, respectively, P = 0.623). The SB group had a higher percentage of patients requiring additional laser applications (21% vs. 7%; P < 0.01) and buckle readjustment surgery (6% vs. 0; P = 0.01), and the PB group had a higher percentage of patients who required postoperative pars plana vitrectomy (30% vs. 17%; P = 0.03).

CONCLUSION

Scleral buckle surgery alone is efficient for the treatment of rhegmatogenous retinal detachment. Its combination with pneumatic retinopexy usually has no significant added value in terms of anatomical reattachment rate. Outcomes of Pneumatic buckling vs Scleral Buckling for RRD.

Hyperbaric oxygen as a model of lens aging in the bovine lens: The effects on lens biochemistry, physiology and optics

Age related nuclear (ARN) cataracts in humans take years to form and so experimental models have been developed to mimic the process in animals as a means of better understanding the etiology of nuclear cataracts in humans. A major limitation with these animal models is that many of the biochemical and physiological changes are not typical of that seen in human ARN cataract. In this review, we highlight the work of Frank Giblin and colleagues who established an in vivo animal model that replicates many of the changes observed in human ARN cataract. This model involves exposing aged guinea pigs to hyperbaric oxygen (HBO), which by causing the depletion of the antioxidant glutathione (GSH) specifically in the lens nucleus, produces oxidative changes to nuclear proteins, nuclear light scattering and a myopic shift in lens power that mimics the change that often precedes cataract development in humans. However, this model involves multiple HBO treatments per week, with sometimes up to a total of 100 treatments, spanning up to eight months, which is both costly and time consuming. To address these issues, Giblin developed an in vitro model that used rabbit lenses exposed to HBO for several hours which was subsequently shown to replicate many of the changes observed in human ARN cataract. These experiments suggest that HBO treatment of in vitro animal lenses may serve as a more economical and efficient model to study the development of cataract. Inspired by these experiments, we investigated whether exposure of young bovine lenses to HBO for 15 h could also serve as a suitable acute model of ARN cataract. We found that while this model is able to exhibit some of the biochemical and physiological changes associated with ARN cataract, the decrease in lens power we observed was more characteristic of the hyperopic shift in refraction associated with ageing. Future work will investigate whether HBO treatment to age the bovine lens in combination with an oxidative stressor such as UV light will induce refractive changes more closely associated with human ARN cataract. This will be important as developing an animal model that replicates the changes to lens biochemistry, physiology and optics observed in human ARN cataracts is urgently required to facilitate the identification and testing of anti-cataract therapies that are effective in humans.

Biocompatibility of intraocular liquid tamponade agents: an update

Intraocular liquids tamponade agents, such as perfluorocarbon liquids (PFCLs), semifluorinated alkanes (SFAs), silicone oils (SOs) and heavy silicone oils (HSOs), are a crucial intraoperative and/or postoperative tool in vitreoretinal surgery, in particular for the management of complex vitreoretinal diseases. However, their use is not without complications, which are potentially severe. Consequently, a growing interest has been devoted to the biocompatibility of these compounds and the adequacy of current regulations that should guarantee their safety. Obviously, an updated knowledge on research findings and potential risks associated to the use of intraocular liquid compounds is essential, not only for vitreoretinal surgeons, but also for any ophthalmologist involved in the management of patients receiving intraocular liquid tamponades. In light of this, the review provides a comprehensive characterisation of intraocular liquid tamponades, in terms of physical and chemical properties, current clinical use and possible complications. Moreover, this review focuses on the safety profile of these compounds, summarising the existing regulation and the available evidence on their biocompatibility.

OUTCOMES OF COMBINED PHACOEMULSIFICATION AND PARS PLANA VITRECTOMY FOR RHEGMATOGENOUS RETINAL DETACHMENT: A Comparative Study

PURPOSE

To evaluate and to compare the anatomical and functional results of phacovitrectomy and pars plana vitrectomy (PPV) alone for phakic rhegmatogenous retinal detachment.

METHODS

Retrospective, comparative case series of 266 phakic eyes that underwent either combined phacovitrectomy or PPV alone for primary retinal detachment. The primary anatomical success rate, the final best-corrected visual acuity, and the refractive outcomes were analyzed.

RESULTS

One hundred and twenty-seven eyes were included in the combined group and 139 in the PPV group. The primary anatomical success rate was 84.3% in the combined group and 89.2% in the PPV group (P = 0.311). One hundred and nine (78.4%) eyes of the PPV group required cataract removal for visual rehabilitation during the follow-up period. There was no significant difference between the two groups in terms of the mean final best-corrected visual acuity (P = 0.185) and mean visual changes (P = 0.470). Overall, combined cataract extraction resulted in a significant myopic shift compared with delayed cataract surgery (P = 0.047).

CONCLUSION

Combined phacoemulsification and PPV is a safe and effective procedure to treat retinal detachment. The anatomical and functional results were comparable with those obtained with PPV and delayed cataract surgery. However, the refractive outcomes were less favorable and shifted toward myopia, especially in macula-off cases.

PHACOVITRECTOMY VERSUS LENS-SPARING VITRECTOMY FOR RHEGMATOGENOUS RETINAL DETACHMENT REPAIR ACCORDING TO THE SURGICAL EXPERIENCE

PURPOSE

To compare the efficacy and safety between lens-sparing vitrectomy and phacovitrectomy for primary rhegmatogenous retinal detachment treatment according to surgical experience.

METHODS

We retrospectively reviewed the medical records of 193 patients with primary rhegmatogenous retinal detachment who underwent either lens-sparing vitrectomy (n = 111) or phacovitrectomy (n = 82). Patients were operated by two experienced surgeons or eight vitreoretinal fellows and had a minimum follow-up of 6 months. Anatomical success rate, postoperative complications, and functional outcomes were compared.

RESULTS

Primary anatomical success rate was 92.8% (103/111) for lens-sparing vitrectomy and 91.5% (75/82) for phacovitrectomy (P = 0.733). The fellows had lower success rate after phacovitrectomy compared with the experts, but not statistically significant (85% [34/40] vs. 97.6% [41/42], P = 0.054). During phacovitrectomy, one zonulysis case in the experts group and four posterior capsular rupture cases in the fellows group were noted. Cystoid macular edema was found only after phacovitrectomy (12.2% [10/82]), and epiretinal membrane occurred more after phacovitrectomy than after lens-sparing vitrectomy (28% [23/82] vs. 8.1% [9/111], P < 0.001). There was no difference in the occurrence of cystoid macular edema and epiretinal membrane after phacovitrectomy between two surgeon groups (P = 0.514, 0.701, respectively).

CONCLUSION

Combined phacoemulsification and vitrectomy has no additional benefit in improving the surgical outcome of primary rhegmatogenous retinal detachment management. Considering the intraoperative and postoperative complications and the relatively low success rate, phacovitrectomy may not be a desirable option in inexperienced surgeons.

Lens densitometry for assessment and prediction of cataract progression after pars plana vitrectomy with C3F8-gas for retinal detachment

Purpose

Lens opacification is a common complication after pars plana vitrectomy (PPV) and knowing its progression would facilitate consulting patients. The purpose of this study was to evaluate a quantitative model for lens-status-monitoring after PPV with C3F8 gas. Our model was evaluated in rhegmatogenous retinal detachment (RRD) patients of various age and lens densitometry (LD).

Methods

Data between March 2018 and March 2020 were evaluated retrospectively. LD measurements of the PentacamHR® Nucleus Staging mode (PNS) were used to quantify lens opacification over time. A mixed-effect regression model was designed, to enable LD predictions at any time postoperatively. Calculations were based on patient’s age and baseline LD as dependent variables. Six patients were randomly excluded during model development, to be used for testing its power afterwards.

Results

34 patients (male 19 [55.9%], female 15 [44.1%]) matched the inclusion criteria. Average age was 58.5 years (32–77;±4.3) and average follow-up was 7.2 months (3,4–23.1;±1,8). Mean baseline LD of the treated and fellow eye before surgery were 10.9% (8.7%-14.8%;±0.8) and 10.7% (8.5%-14.1%;±0.6), respectively. Using our prediction model, LD values for the six pre-selected patients closely match the observed data with an average deviation of 1.07%.

Conclusions

Evaluation of age and baseline LD using a mixed-effect regression model might predict cataract progression in RRD patients treated with PPV and C3F8-gas. Such a tool could be considered during cataract surgery consultation in these patients.

Clinical Outcomes of Rhegmatogenous Retinal Detachment Treated With Pneumatic Retinopexy

IMPORTANCE

Pneumatic retinopexy (PR) is the only clinic-based method of rhegmatogenous retinal detachment (RRD) repair. Registry-acquired clinical practice setting outcomes data with this procedure have not yet been reported.

OBJECTIVE

To describe the clinical outcomes associated with RRD treated primarily with PR.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective cohort study, data from patients 19 years and older with noncomplex RRD treated at academic and private ophthalmology practices participating in the American Academy of Ophthalmology IRIS Registry (Intelligent Research in Sight) were analyzed. Data were collected from January 1, 2013, to December 31, 2019, and data were analyzed from January to December 2020.

EXPOSURES

Data from the IRIS Registry were queried for eyes that underwent PR for noncomplex RRD and had at least 3 months of follow-up. Cases were identified by a combination of diagnosis code for RRD and a Current Procedural Terminology code for PR.

MAIN OUTCOMES AND MEASURES

The number of eyes that achieved single-operation success (SOS), defined as retinal reattachment without a subsequent retinal detachment surgery or repeated PR.

RESULTS

Of 9553 included patients, 5827 (61.0%) were male, and the mean (SD) age was 62 (10) years. A total of 9659 eyes were identified. SOS was achieved in 6613 eyes (68.5%). Best-corrected visual acuity significantly differed 9 to 12 months after treatment between the SOS group, with a mean of 0.24 logMAR (95% CI, 0.23-0.25; approximate Snellen equivalent, 20/35), and the single-operation failure group, with a mean of 0.43 logMAR (95% CI, 0.40-0.46; approximate Snellen equivalent, 20/54). Among all patients, the mean time to maximal visual recovery was 268 days (95% CI, 260-276). Endophthalmitis was observed in 3 eyes (0.03%). SOS was associated with female sex (odds ratio, 1.51; 95% CI, 1.38-1.65), while current smoking status was associated single-operation failure (odds ratio, 0.78; 95% CI, 0.68-0.91).

CONCLUSIONS AND RELEVANCE

In this registry-based study, which encompasses a large number of eyes drawn from multiple, heterogenous electronic health record systems, SOS was achieved in 68.5% of eyes with noncomplex RRD treated by primary PR. It is unknown how these outcomes would have compared with other methods of RRD repair in this cohort.

Cataract Following Pars Plana Vitrectomy: A Review

Introduction: The indications for pars plana vitrectomy (PPV) have increased over the years. The vitreous is no longer considered an inert ocular structure and it is well known that its removal has anatomical and physiological consequences. The vitreous is no longer considered an inert ocular structure. The vitreous plays a key role as an intraocular physiologic oxygen regulator. In order to maintain its transparency, the crystalline lens needs protection from an excessive oxygen exposure. PPV leads to progression of nuclear sclerosis in most eyes.Methods: A systematic review of the literature was conducted using Embase and Medline databases. Articles studying the physiology, pathogenesis and surgical treatment of cataract after PPV were included in this review.Results: The pathogenesis of cataract formation after PPV remains unclear. Predisposing factors include advanced patient age, preexisting nuclear sclerosis, light toxicity, intraoperative oxidation of lens proteins, use of silicone oil or intravitreal gas, mechanical trauma and the duration of exposure to an irrigating solution.Conclusion: Cataract surgery in vitrectomized eyes presents with more technical difficulties, is more challenging and often has a higher risk of intraoperative and postoperative complications than in non vitrectomized eyes. There is no standardized technique or management in these cases; therefore, it requires more precautions during surgery.

Parsplana vitrectomy alone versus parsplana vitrectomy combined with phacoemulsification for the treatment of rhegmatogenous retinal detachment: a randomized study

BACKGROUND

To compare parsplana vitrectomy (PPV) with and without phacoemulsification to treat rhegmatogenous retinal detachment (RRD).

METHODS

Subjects aged 48-65 years with RRD in a phakic eye due to superior retinal tears with an overall extension of retinal breaks < 90° underwent to PPV alone (group A); or PPV plus phacoemulsification (phacovitrectomy, PCV, group B). Post-operative follow-up visits occurred at 1 week, 1 month (m1), 3 months (m3), and 6 months (m6) after surgery. The main outcome was the rate of retinal reattachment. Secondary outcomes included best-corrected visual acuity (BCVA), intraocular pressure (IOP), central macular thickness (CMT), and cataract progression (in the lens-sparing [PPV-alone] group).

RESULTS

In this initial phase of the study a total of 59 patients (mean age: 55 years, 59 eyes) were enrolled: 29 eyes in group A and 30 eyes in group B. Both groups had similar gas tamponade. During the follow-up there were three cases of RRD recurrence in group A and one in group B. The relative risk of recurrence in group A was 3.22 times higher but the difference was not significant (p = 0.3). The two groups were also similar in terms of BCVA and IOP variation. At m3, CMT was significantly higher in group B (p = 0.014). In group A, cataract progression was significant at m6 (p = 0.003).

CONCLUSIONS

In a cohort of RRD patients selected according to their preoperative clinical characteristics, PPV was comparable to PCV in terms of the rate of retinal reattachment after 6 months.

TRIAL REGISTRATION

ISRCTN15940019 . Date registered: 15/01/2021 (retrospectively registered).

Methodological Challenges in the Economic Evaluation of a Gene Therapy for RPE65-Mediated Inherited Retinal Disease: The Value of Vision

The emergence of gene therapies challenge health economists to evaluate interventions that are often provided to a small patient population with a specific gene mutation in a single dose with high upfront costs and uncertain long-term benefits. The objective of this study was to illustrate the methodological challenges of evaluating gene therapies and their implications by discussing four economic evaluations of voretigene neparvovec (VN) for the treatment of RPE65-mediated inherited retinal disease. The checklist for economic evaluations of gene therapies of Drummond et al. was applied to the economic evaluations of VN performed by US Institute for Clinical and Economic Review, two country adaptations of the company model in the UK and the Netherlands, and another US publication. The main differences in methodological choices and their impact on cost-effectiveness results were assessed and further explored with sensitivity analyses using the Dutch model. To enable comparison between the economic evaluations, costs were converted to US dollars. Different methodological choices were made in the economic evaluations of VN resulting in large differences in the incremental cost-effectiveness ratio varying from US$79,618 to US$643,813 per QALY. The chosen duration of treatment effect, source of utility values, discount rate and model structure had the largest impact on the cost-effectiveness. This study underlines the findings from Drummond et al. that standard methods can be used to evaluate gene therapies. However, given uncertainty about (particularly long-term) outcomes of gene therapies, guidance is required on the acceptable extrapolation of treatment effect of gene therapies and on how to handle the uncertainty around this extrapolation in scenario and sensitivity analyses to aid health technology assessment research and align submissions of future gene therapies.

Phacoemulsification outcomes and complications in vitrectomised versus non-vitrectomised eyes

Clinical relevance: Pars plana vitrectomy techniques have evolved in the recent years and the number of patients undergoing phacoemulsification for post-vitrectomy cataract has increased. Eye-care practitioners need to be aware of intraoperative complications and post-operative outcomes in previously vitrectomised eyes.Background: The aim of the present study is to compare the outcomes and related complications of phacoemulsification in previously vitrectomised versus non-vitrectomised eyes.Methods: This is a retrospective case-control study. Visual acuity, refractive outcomes, intra- and post-operative complications were analysed in consecutive phacoemulsification patients between January 2015 and August 2017. Patients with no post-operative data were excluded.Results: One hundred and forty-nine previously vitrectomised eyes and 608 non-vitrectomised eyes were included in the analysis. Previous pars plana vitrectomy was associated with worse logMAR visual acuity pre-operatively (0.75 ± 0.54 vs. 0.40 ± 0.33, p < 0.0001) and post-operatively (0.15 ± 0.29 vs. 0.09 ± 0.22, p = 0.014). There were no statistically significant differences between the two groups regarding refractive outcomes (p = 0.393) or posterior capsule rupture rate (p = 0.223). Previous pars plana vitrectomy was associated with a higher risk of post-operative macular oedema (p = 0.046) and posterior capsule opacification (p < 0.0001).Conclusions: Previous pars plana vitrectomy was not associated with a higher risk of intraoperative complications. However, a higher incidence of cystoid macular oedema and posterior capsule opacification were identified in the present study. Further research can provide insight into the mechanisms involved and any appropriate prevention strategies for these conditions.

Long-term outcomes of vitrectomy for proliferative diabetic retinopathy

PURPOSE

To investigate the long-term outcomes of patients who underwent vitrectomy for proliferative diabetic retinopathy.

METHODS

Cumulative incidences were calculated for low vision (<0.3), re-vitrectomy in the study eye and fellow eye vitrectomy. To identify potential prognostic factors that associate with these outcomes, we used multivariable Cox regression models.

RESULTS

In a total of 217 patients, we found 1-, 5- and 10-year cumulative incidences of low vision in the study eye of 24%, 31% and 39%, respectively. For both eyes, these rates were, respectively, 10%, 14% and 14%. Low vision in both eyes was associated with higher age and worse contralateral visual acuity. The 1-, 5- and 10-year cumulative incidences for re-vitrectomy in the study eye were 16%, 27% and 27%, respectively, and for a vitrectomy in the fellow eye 24%, 40% and 54%, respectively. Re-vitrectomy of the study eye was associated with worse contralateral visual acuity, while vitrectomy of the fellow eye was associated with shorter diabetes duration, worse contralateral visual acuity, higher HbA1c level and worse diabetic retinopathy severity stage of the fellow eye.

CONCLUSION

Functional visual acuity in at least one eye was achieved or preserved in most patients. After 10 years, about a quarter of all patients underwent a re-vitrectomy, while more than half of the patients needed a vitrectomy of the fellow eye. Knowledge of these long-term outcomes is essential when counselling patients for a vitrectomy.

Epiretinal membrane vitrectomy: outcomes with or without cataract surgery and a novel prognostic factor for cystoid macular edema

PURPOSE

To assess the outcomes of vitrectomy with or without cataract surgery for the treatment of idiopathic ERM in phakic eyes and evaluate predictors of functional and anatomical outcomes.

METHODS

Retrospective cohort of consecutive phakic ERM eyes distributed in three groups: a) combined (phacovitrectomy) group, b) PPV-only group, and c) consecutive group (PPV followed by cataract surgery). Main outcomes were final visual acuity (VA) and cystoid macular edema (CME) occurrence. Potential predictors of VA or CME included clinical variables and SD-OCT parameters.

RESULTS

A total of 108 eyes were included in this study. There were no differences in the final VA between consecutive and combined groups (0.22 vs 0.10 logMAR, p = 0.851). Twelve eyes from the combined group (23%) and one eye from the PPV-only group presented CME (p = 0.001). There were no differences between postoperative CME occurrence in combined versus consecutive group (12 vs 7, p = 0.38). The presence of cotton-ball sign predicted the development of CME [OR 2.86 (95%CI 1.01-8.18), p = 0.049] while separated ERM-ILM complex was found to be protective [OR 0.25 (95%CI 0.08-0.77), p = 0.015].

CONCLUSIONS

Functional and anatomical results of PPV with ERM and ILM peeling combined with cataract surgery was equivalent to the consecutive procedure, with both strategies being effective. Separated ERM-ILM complex has prognostic value in these patients, as its presence at baseline was found to be protective for postoperative CME.

Combined versus Sequential Phacoemulsification and Pars Plana Vitrectomy: A Meta-Analysis

TOPIC

It is unclear whether differences exist in efficacy and safety between combined versus sequentially performed phacoemulsification and pars plana vitrectomy (phaco-PPV).

CLINICAL RELEVANCE

This meta-analysis aimed to compare the efficacy and incidence of complications between these surgical methods.

METHODS

Ovid MEDLINE, EMBASE, and Cochrane CENTRAL were searched for articles reporting the efficacy and safety of combined versus sequential phaco-PPV for any indication. The primary outcomes were postoperative best-corrected visual acuity (BCVA) and mean absolute refractive error from target (RET). Secondary outcomes included efficacy outcomes and postoperative complications. Meta-analysis was conducted using a random effects model in all cases. Risk of bias assessment was performed using the Cochrane risk of bias assessment tool for randomized trials and ROBINS-I tool for observational studies.

RESULTS

Of the 5410 articles identified, 1 randomized controlled trial and 14 comparative studies were included, with 1407 and 951 eyes in the combined and sequential surgery groups, respectively. Mean age was 62.71 ± 6.16 years and 44% (range, 32.1%-70%) of eyes were from men. The mean baseline BCVA was 0.88 ± 0.59 logarithm of the minimum angle of resolution units (Snellen equivalent, 20/152). The meta-analysis showed no significance between groups in postoperative mean BCVA (P = 0.76) and mean absolute RET (P = 0.46). The risks of synechiae formation (risk ratio [RR], 2.74; 95% confidence interval [CI], 1.83-4.11; P < 0.001), fibrin formation (RR, 2.81; 95% CI, 1.84-4.30; P < 0.001), and intraoperative or postoperative retinal detachment (RR, 2.65; 95% CI, 1.08-6.47; P = 0.03) were significantly higher after combined surgery. However, the risks of posterior capsular tear (RR, 0.43; 95% CI, 0.25-0.73; P = 0.002) and macular hole nonclosure or reopening (RR, 0.18; 95% CI, 0.03-0.93; P = 0.04) were significantly lower in the combined group.

DISCUSSION

No significant differences were found in visual and refractive outcomes between combined and sequential phaco-PPV, whereas differences existed in certain safety outcomes. These conclusions remain preliminary, as most evidence is derived from low- to moderate-quality retrospective studies. Given the variability in outcome reporting and associated heterogeneity, future randomized controlled trials are needed.

Vitrectomy with air tamponade and cryotherapy for retinal detachment repair without perfluorocarbon use: A UK 12-month prospective case series

INTRODUCTION

Rhegmatogenous retinal detachment (RRD) is commonly managed by pars plana vitrectomy (PPV). Gas tamponade has significant clinical and quality of life factors that affect the patient. Using shorter acting air tamponade, intuitively leads to surgical concern for higher rate of primary detachment. To circumvent this, surgeons advocate the use of perfluorocarbon to maximise sub-retinal-fluid drainage when using air tamponade and/or avoid using cryotherapy due to longer duration for scar formation relative to laser. These steps are a deviation from traditional technique for otherwise routine primary RRD repair and discourages popularisation of using air tamponade despite the benefits to patients.

METHOD

Prospective 12-month, single centre, single surgeon, consecutive study from January to December 2019. Inclusion criteria was as per based on the pneumatic retinopexy versus vitrectomy for retinal detachment: (i) single retinal break or group of breaks, no larger than 1-clock-hour (30°), in detached retina; (ii) all breaks in detached retina lie above the 8 to 4 o'clock meridian; and (iii) breaks or lattice degeneration in attached retina at any location. We excluded PVR formation and RRD in the inferior 4 o'clock hours.

RESULTS

We report primary and final success rate of 96% and 100%, respectively in 23 eyes (22 macular-on and one macular-off) with RRD eyes in a 12-month period. Cryopexy was utilised in 65% patients and in isolation in 23% with no perfluorocarbon use in all eyes.

CONCLUSION

We show cryotherapy can be used safely in AT-RRD without PFCL in RRD fulfilling PIVOT trial criteria with minimal cataract formation and IOP spikes and faster post-operative visual rehabilitation.

Intravitreal ranibizumab for persistent diabetic vitreous haemorrhage: a randomised, double-masked, placebo-controlled feasibility study

PURPOSE

To determine the feasibility of a definitive study of intravitreal ranibizumab to promote the clearance of persistent diabetic vitreous haemorrhage and thereby avoid vitrectomy.

METHODS

This randomised, double-masked, placebo-controlled feasibility study recruited 24 participants with persistent diabetic vitreous haemorrhage listed for pars plana vitrectomy. Participants were randomised to a single 0.5-mg intravitreal ranibizumab injection or a single subconjunctival saline injection. The primary outcome measure was the number of participants requiring pars plana vitrectomy at week 7.

RESULTS

Eight of 12 participants (66.7%) in the ranibizumab group required vitrectomy at week 7 versus 12 of 12 (100%) in the placebo group (absolute risk reduction 33.3%, 95% confidence interval 2.1-70.7%; p = 0.09). One additional eye in the ranibizumab group required vitrectomy by 12 months. Mean visual acuity letter score at 12 months was 72.7 ± 12.3 in the ranibizumab group and 75.1 ± 10.1 in the placebo group. Safety was similar across groups.

CONCLUSION

Intravitreal ranibizumab may reduce the likelihood of proceeding to vitrectomy in patients with persistent, dense diabetic vitreous haemorrhage. Further studies appear feasible and justified.

Local dry vitrectomy combined with segmental scleral buckling and viscoelastic tamponade for rhegmatogenous retinal detachment with vitreous traction

AIM

To demonstrate local dry vitrectomy combined with segmental scleral buckling and viscoelastic tamponade for the treatment of partial rhegmatogenous retinal detachment (RRD) with local vitreous traction in patients at high-risk for proliferative vitreoretinopathy (PVR).

METHODS

Eleven eyes of 11 patients were retrospectively studied, including 5 retinal dialysis and 6 retinal detachment (RD; 5 eyes with peripheral retinal hole and 1 eye with giant tear). All patients exhibited partial RD and local vitreous traction. Combined local dry vitrectomy without conventional infusion and segmental scleral buckling was performed. Viscoelastic fluid was injected into the vitreous cavity if needed. Demographic information, preoperative and post-operative complications, and outcomes were recorded.

RESULTS

The mean age of the patients at presentation was 26.55±13.52y. All 11 patients obtained retinal reattachment after a single surgical intervention. Postoperative visual acuities were improved or remained stable in all patients. None of them developed complications, except for temporary mildly increased intraocular pressure in 3 cases.

CONCLUSION

Combined local dry vitrectomy and segmental scleral buckling are effective for patients of RRD with local vitreous traction. The technique avoids many complications associated with regular surgery and was minimally invasive to both the external and internal eye.

Glutathione Improves the Antioxidant Activity of Vitamin C in Human Lens and Retinal Epithelial Cells: Implications for Vitreous Substitutes

PURPOSE

Tissues in the eye are particularly susceptible to oxidative damage due to light exposure. While vitamin C (ascorbic acid) has been noted as a vital antioxidant in the vitreous humor, its physiological concentration (1-2 mM) has been shown to be toxic to retinal and lens epithelial cells in in vitro cell culture. We have explored adding vitamin C to hydrogel vitreous substitutes as a potential therapeutic to prevent oxidative damage to intraocular tissues after vitrectomy. However, vitamin C degrades rapidly even when loaded at high concentrations, limiting its long-term effectiveness. Glutathione, another antioxidant found abundantly in the lens at concentrations of 2-10 mM, was proposed to be used in conjunction with vitamin C.

METHODS

Cell viability and reactive oxygen species activity of human retinal and lens epithelial cells treated with various combinations of vitamin C, glutathione, hydrogen peroxide, and a hydrogel vitreous substitute were determined using CellTiter-Glo luminescent cell viability assay and dichlorofluorescein assay, respectively. The vitamin C remaining in hydrogel vitreous substitute or glutathione-vitamin C solutions was determined using a microplate reader at 265 nm wavelength, compared against standard solutions with known concentrations.

RESULTS

Glutathione protected the lens and retinal cells from the negative effect of vitamin C on cell viability and prolonged the antioxidant effect of vitamin C in vitro. While the detected reading of pure vitamin C solution decreased rapidly from 100% to 10% by 3 days, glutathione provided a significant extension to vitamin C stability, with 70% remaining after 14 days when the glutathione was used at physiological concentrations found in the lens (2-10 mM).

CONCLUSIONS

These results indicate glutathione might be an effective addition to vitamin C in intraocular implants, including potential vitreous substitutes, and warrants additional studies on the effectiveness of the vitamin C - glutathione combination in preventing oxidative stress post-vitrectomy.

Characteristics, fates and complications of long-term silicone oil tamponade after pars plana vitrectomy

BACKGROUND

Silicone oil tamponade has become a mainstay in treatment of advanced retinal detachment due to multiple etiologies. The aim of this study is to assess the characteristics, fates and complications of long-term silicone oil tamponade after par plana vitrectomy (PPV), and to compare the outcomes of different silicone oil viscosities used in a cohort of consecutive patients.

METHODS

This is a retrospective comparative case series of eyes undergoing vitrectomy with silicone oil tamponade for retinal detachment by a single surgeon using different oil viscosities that were followed for one year with the silicone oil in situ. Visual acuity (VA), intraocular pressure (IOP) and complications associated with the follow up period were analyzed and compared.

RESULTS

Eighty-five eyes of 85 patients were included in this study. Forty three patients had 1000 centistoke (cs) oil injected and 42 patients had 5000cs oil utilized. Demographic, cause of retinal detachment and preoperative ocular characteristics were similar in both groups. Long term complications in both groups included ocular hypertension (67.4% vs 66.7%), keratopathy due to silicone oil emulsification and migration to the anterior chamber (7.0% vs 11.9%), recurrent retinal detachment (4.7% vs 19%) and epiretinal membrane formation (7% vs 19%). In the 1000cs oil group, there was no significant difference between baseline IOP and any subsequent visit. There was a significant difference between baseline IOP and visits at day 1 (with IOP difference of 2.61 mmHg (±6.5)) (p = 0.028), 1 month (with IOP difference of 3.52 mmHg (±8.1)) (p = 0.026), 4 months (with IOP difference of 6.38 mmHg (±9.3)) (p = 0.005), and one year (with IOP difference of 4.24 mmHg (±11.1)) (p = 0.048), all higher in the post-operative period in the 5000cs oil group. Excluding the first post-operative day, no significant difference was found for VA between baseline visits and subsequent visits for either silicone oil groups.

CONCLUSION

In this cohort of patients with long-term silicone oil tamponade after PPV to treat retinal detachment, IOP increased significantly in patients who received 5000cs silicone oil. There was no significant difference between other complication rates in patients receiving either oil viscosities. Long term silicone oil tamponade remains a viable option in certain cases, and a vigilant follow up for complications is necessary to limit any adverse effects and improve visual and surgical outcomes.

Phacoemulsification in vitrectomized eyes: Maintaining the stability of the anterior chamber via a new technique

Fluctuating anterior chamber depth and reverse pupillary block are the most common problems encountered during phacoemulsification following pars plana vitrectomy in cases of cataracts. The sudden deepening of the anterior chamber makes the surgical procedure more cumbersome and increases the risk of intraoperative complications. To solve this problem, we describe a method of balancing the pressure of the anterior and posterior chamber by using a syringe with a flushing needle to inject balanced salt solution into the posterior chamber via the gap between the iris and the anterior capsule of the lens. This technique is especially suitable for complicated cataracts following previous pars plana vitrectomy and high myopia-complicated cataracts. This technique yielded promising results in reducing the difficulties that occur during surgical procedures, reduced the risk of intraoperative complications and simplified the intraocular lens implantation.