Air versus fluorinated gas tamponades in pars plana vitrectomy treatment for primary rhegmatogenous retinal detachment

FUNCTIONAL AND ANATOMICAL OUTCOMES AFTER SHORT-TERM HEAVY SILICONE OIL ENDOTAMPONADE FOR INFERIOR RHEGMATOGENOUS RETINAL REDETACHMENT: A Pilot Study

PURPOSE

To assess the success of the short-term location of the heavy silicone oil (Densiron 68, HSO) as endotamponade after pars plana vitrectomy for rhegmatogenous complex retinal redetachment.

METHODS

Consecutive, retrospective, nonrandomized, pilot study was conducted. Twenty-two eyes of 22 patients with complex inferior retinal redetachment previously tamponade with gas (SF6 or C3F8) or 1000 cSt standard silicone oil (SSO) were selected. All were treated with HSO endotamponade, and its removal was performed after 1 month. The main outcomes were best-corrected visual acuity and postoperative complications after the HSO removal.

RESULTS

Of the 22 eyes, 10 were treated with SSO endotamponade, 3 with fluorinated gas 14% C3F8, and 9 with 20% SF6 at first surgery. In all eyes, a complex inferior retinal redetachment was observed after the first surgery, in 1 month to 3 months after silicone oil removal or gas endotamponade introduction. In 10 eyes, the proliferative vitreoretinopathy (Grade B or C 1-3) was found. The main best-corrected visual acuity before HSO removal was 0.55 ± 0.20 the logarithm of the minimum angle of resolution (range 0.4-0.7) and after the HSO removal, it was 0.32 ± 0.29 the logarithm of the minimum angle of resolution (0.1-0.4). Among the postoperative complications, only in four eyes the macular edema was found (medically resolved), in four eyes an increase of intraocular pressure, and none of these developed the epiretinal membrane.

CONCLUSION

The main purpose of this study is to establish a short-term HSO endotamponade in eyes with complex retinal detachment recurrences, reducing the possible postoperative complications and having a better prognosis for visual acuity outcomes.

Routine use of filtered air as endotamponade in the management of primary rhegmatogenous retinal detachment

PURPOSE

To evaluate the safety and efficacy of filtered air as endotamponade in the management of primary rhegmatogenous retinal detachment (RRD) treated with pars plana vitrectomy (PPV) and complete drainage of subretinal fluid.

METHODS

For this retrospective study, we reviewed the medical charts of 273 patients (275 eyes) who consecutively underwent PPV, subretinal fluid drainage and filtered air tamponade to treat primary RRD between 2018 and 2022. As primary outcome we evaluated the anatomical success considered as retinal reattachment after single surgery. As secondary outcomes: final mean best corrected distance visual acuity (BCDVA), complications, and mean intraocular pressure (IOP) trends.

RESULTS

The anatomical success was reached by 262 (95.6%) of cases. Mean BCDVA improved from 0.73 LogMAR at baseline, to 0.21 LogMAR at the end of follow-up. As complications we recorded: 5 cases of clinically relevant macular pucker, 1 full thickness macular hole, and 1 PFO bubble under the retina. The mean IOP remained on normal values during the overall follow-up period.

Exploring AI-chatbots' capability to suggest surgical planning in ophthalmology: ChatGPT versus Google Gemini analysis of retinal detachment cases

BACKGROUND

We aimed to define the capability of three different publicly available large language models, Chat Generative Pretrained Transformer (ChatGPT-3.5), ChatGPT-4 and Google Gemini in analysing retinal detachment cases and suggesting the best possible surgical planning.

METHODS

Analysis of 54 retinal detachments records entered into ChatGPT and Gemini's interfaces. After asking 'Specify what kind of surgical planning you would suggest and the eventual intraocular tamponade.' and collecting the given answers, we assessed the level of agreement with the common opinion of three expert vitreoretinal surgeons. Moreover, ChatGPT and Gemini answers were graded 1-5 (from poor to excellent quality), according to the Global Quality Score (GQS).

RESULTS

After excluding 4 controversial cases, 50 cases were included. Overall, ChatGPT-3.5, ChatGPT-4 and Google Gemini surgical choices agreed with those of vitreoretinal surgeons in 40/50 (80%), 42/50 (84%) and 35/50 (70%) of cases. Google Gemini was not able to respond in five cases. Contingency analysis showed significant differences between ChatGPT-4 and Gemini (p=0.03). ChatGPT's GQS were 3.9±0.8 and 4.2±0.7 for versions 3.5 and 4, while Gemini scored 3.5±1.1. There was no statistical difference between the two ChatGPTs (p=0.22), while both outperformed Gemini scores (p=0.03 and p=0.002, respectively). The main source of error was endotamponade choice (14% for ChatGPT-3.5 and 4, and 12% for Google Gemini). Only ChatGPT-4 was able to suggest a combined phacovitrectomy approach.

CONCLUSION

In conclusion, Google Gemini and ChatGPT evaluated vitreoretinal patients' records in a coherent manner, showing a good level of agreement with expert surgeons. According to the GQS, ChatGPT's recommendations were much more accurate and precise.

Outcomes of short- versus long-acting gas tamponades in vitrectomy for rhegmatogenous retinal detachment

BACKGROUND

In vitrectomy for rhegmatogenous retinal detachment, long-acting gas tamponades (LGT) such as C3F8 or C2F6 may improve surgical success rate due to their prolonged effect compared to a short-acting gas tamponade (SGT) with SF6. On the other hand, SGT allow a significantly faster visual rehabilitation after surgery and may reduce the risk of gas-related complications. As comparative data in retinal detachment surgery is limited, we assessed the outcomes of vitrectomies using either LGT or SGT.

METHODS

We retrospectively analyzed 533 eyes of 524 consecutive patients diagnosed with primary rhegmatogenous retinal detachment not complicated by proliferative vitreoretinopathy (PVR) and treated by vitrectomy at two clinical sites. Depending on the site the patients presented at, they received either preferentially LGT (study site 1) or SGT (study site 2). Retinal re-detachment rates during a period of 6 months following surgery were analyzed.

RESULTS

At study site 1, 254 of 278 eyes (91.4%) were treated by LGT (C3F8 72.3%; C2F6 19.1%), whereas at study site 2, 246 of 255 eyes (96.5%) received SGT (SF6). Rates of retinal re-detachment in the LGT- and SGT-treated groups were similar with 23 of 254 eyes (9.1%) and 24 of 246 eyes (9.8%), respectively (p = 0.9). Median time to re-detachment was 5.7 weeks in the LGT-treated group and 4.4 weeks in the SGT-treated group (p = 0.4).

CONCLUSION

In rhegmatogenous retinal detachment repair by vitrectomy, the use of SGT results in comparable rates of successful retinal re-attachment as LGT. Given the faster visual rehabilitation with SGT, these results suggest SGT as a sensible alternative to LGT in surgery of retinal detachment without PVR.

DO DAILY ACTIVITIES AFFECT GAS TAMPONADE‒RETINA CONTACT AFTER PARS PLANA VITRECTOMY?: A Computational Fluid Dynamics Study

PURPOSE

To calculate the retinal surface alternatively in contact with gas and aqueous because of fluid sloshing during daily activities such as ocular saccade, turning the head, standing up, and being a passenger of a braking car.

METHODS

Fluid dynamics of aqueous and gas tamponade was reproduced using computational methods using the OpenFOAM open-source library. The double-fluid dynamics was simulated by the volume of fluid method and setting the contact angle at the aqueous-gas-retina interface.

RESULTS

Sloshing increased the retinal surface in contact with aqueous by 13% to 16% regardless of fill rate and standing up determined the largest area of wet retina, followed by car braking, head rotation, and ocular saccade ( P < 0.001). All activities except the ocular saccade determined a significant increase in the surface of retina in contact with the aqueous ( P < 0.005). Car braking induced the highest shear stress (6.06 Pa); standing up determined the highest specific impulse and saccade the lowest.

CONCLUSION

Daily activities instantaneously reduce the amount of retina consistently in contact with gas tamponade and increase shear stress giving aqueous a potential access to the subretinal space regardless of patients' compliance.

Anti-vascular endothelial growth factors in combination with vitrectomy for complications of proliferative diabetic retinopathy

BACKGROUND

Vitrectomy is an established treatment for the complications of proliferative diabetic retinopathy (PDR). However, a number of complications can occur during and after vitrectomy for PDR. These include bleeding and the creation of retinal holes during surgery, and bleeding, retinal detachment and scar tissue on the retina after surgery. These complications can limit vision, require further surgery and delay recovery. The use of anti-vascular endothelial growth factor (anti-VEGF) agents injected into the eye before surgery has been proposed to reduce the occurrence of these complications. Anti-VEGF agents can reduce the amount and vascularity of abnormal new vessels associated with PDR, facilitating their dissection during surgery, reducing intra- and postoperative bleeding, and potentially improving outcomes.

OBJECTIVES

To assess the effects of perioperative anti-VEGF use on the outcomes of vitrectomy for the treatment of complications for proliferative diabetic retinopathy (PDR).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 6); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; ClinicalTrials.gov and the WHO ICTRP. The date of the search was 22 June 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that looked at the use of anti-VEGFs and the incidence of complications in people undergoing vitrectomy for PDR.   DATA COLLECTION AND ANALYSIS: Two review authors independently assessed and extracted the data. We used the standard methodological procedures expected by Cochrane. The critical outcomes of the review were the mean difference in best corrected visual acuity (BCVA) between study arms at six (± three) months after the primary vitrectomy, the incidence of early postoperative vitreous cavity haemorrhage (POVCH, within four weeks postoperatively), the incidence of late POVCH (occurring more than four weeks postoperatively), the incidence of revision surgery for POVCH within six months, the incidence of revision surgery for recurrent traction/macular pucker of any type and/or rhegmatogenous retinal detachment within six months and vision-related quality of life (VRQOL) measures. Important outcomes included the proportion of people with a visual acuity of counting fingers (1.8 logMAR or worse), the number of operative retinal breaks reported and the frequency of silicone oil tamponade required at time of surgery.

MAIN RESULTS

The current review includes 28 RCTs that looked at the pre- or intraoperative use of intravitreal anti-VEGFs to improve the outcomes of pars plana vitrectomy for complications of PDR. The studies were conducted in a variety of countries (11 from China, three from Iran, two from Italy, two from Mexico and the remaining studies from South Korea, the UK, Egypt, Brazil, Japan, Canada, the USA, Indonesia and Pakistan). The inclusion criteria for entry into the studies were the well-recognised complications of proliferative retinopathy: non-clearing vitreous haemorrhage, tractional retinal detachment involving the macula or combined tractional rhegmatogenous detachment. The included studies randomised a total of 1914 eyes.  We identified methodological issues in all of the included studies. Risk of bias was highest for masking of participants and investigators, and a number of studies were unclear when describing randomisation methods and sequence allocation. Participants receiving intravitreal anti-VEGF in addition to pars plana vitrectomy achieved better BCVA at six months compared to people undergoing vitrectomy alone (mean difference (MD) -0.25 logMAR, 95% confidence interval (CI) -0.39 to -0.11; 13 studies, 699 eyes; low-certainty evidence). Pre- or intraoperative anti-VEGF reduced the incidence of early POVCH (12% versus 31%, risk ratio (RR) 0.44, 95% CI 0.34 to 0.58; 14 studies, 1038 eyes; moderate-certainty evidence). Perioperative anti-VEGF use was also associated with a reduction in the incidence of late POVCH (10% versus 23%, RR 0.47, 95% CI 0.30 to 0.74; 11 studies, 579 eyes; high-certainty evidence). The need for revision surgery for POVCH occurred less frequently in the anti-VEGF group compared with control, but the confidence intervals were wide and compatible with no effect (4% versus 13%, RR 0.44, 95% CI 0.15 to 1.28; 4 studies 207 eyes; moderate-certainty evidence). Similar imprecisely measured effects were seen for revision surgery for rhegmatogenous retinal detachment (5% versus 11%, RR 0.50, 95% CI 0.15 to 1.66; 4 studies, 145 eyes; low-certainty evidence).  Anti-VEGFs reduce the incidence of intraoperative retinal breaks (12% versus 31%, RR 0.37, 95% CI 0.24 to 0.59; 12 studies, 915 eyes; high-certainty evidence) and the need for silicone oil (19% versus 41%, RR 0.46, 95% CI 0.27 to 0.80; 10 studies, 591 eyes; very low-certainty evidence). No data were available on quality of life outcomes or the proportion of participants with visual acuity of counting fingers or worse.

AUTHORS' CONCLUSIONS

The perioperative use of anti-VEGF reduces the risk of late POVCH, probably results in lower early POVCH risk and may improve visual outcomes. It also reduces the incidence of intraoperative retinal breaks. The evidence is very uncertain about its effect on the need for silicone oil tamponade. The reported complications from its use appear to be low. Agreement on variables included and outcome standardisation is required in trials studying vitrectomy for PDR.

Air versus Gas Tamponade for Primary Rhegmatogenous Retinal Detachment: A Systematic Review and Meta-Analysis

BACKGROUND

Air tamponade's effectiveness in treatment of rhegmatogenous retinal detachment (RRD) remains unclear.

OBJECTIVE

We aimed to review the surgical outcomes between air and gas tamponade after vitrectomy for RRD.

METHOD

PubMed, Cochrane Library, EMBASE, and Web of Science were reviewed. The study protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO CRD42022342284). The primary outcome was the primary anatomical success after vitrectomy. The secondary outcome was the prevalence of postoperative ocular hypertension. Certainty of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation system.

RESULTS

Ten studies involving 2,677 eyes were included. One study was randomized, and the others were non-randomized. The primary anatomical success after vitrectomy was not significantly different between the air and gas groups (odds ratio [OR], 1.00; 95% confidence interval [CI], 0.68-1.48). The risk of ocular hypertension was significantly lower in the air group (OR: 0.14; 95% CI: 0.09-0.24). The certainty of evidence regarding air tamponade having a comparable anatomical outcome and lower frequency of postoperative ocular hypertension in treatment of RRD were low.

DISCUSSION

The current evidence base for tamponade selection in treatment of RRD has several major limitations. Further appropriately designed studies are needed to guide tamponade selection.

Vitreous Substitutes from Bench to the Operating Room in a Translational Approach: Review and Future Endeavors in Vitreoretinal Surgery

Vitreous substitutes are indispensable tools in vitreoretinal surgery. The two crucial functions of these substitutes are their ability to displace intravitreal fluid from the retinal surface and to allow the retina to adhere to the retinal pigment epithelium. Today, vitreoretinal surgeons can choose among a plethora of vitreous tamponades, and the tamponade of choice might be difficult to determine in the ever-expanding range of possibilities for a favorable outcome. The currently available vitreous substitutes have disadvantages that need to be addressed to improve the surgical outcome achievable today. Herein, the fundamental physical and chemical proprieties of all vitreous substitutes are reported, and their use and clinical applications are described alongside some surgical techniques of intra-operative manipulation. The major upcoming developments in vitreous substitutes are extensively discussed, keeping a translational perspective throughout. Conclusions on future perspectives are derived through an in-depth analysis of what is lacking today in terms of desired outcomes and biomaterials technology.