INTRAOCULAR PRESSURE INSTABILITY AFTER 23-GAUGE VITRECTOMY

Twenty-seven-gauge vitrectomy: a consecutive, single-centre case series with exclusive use over a 4-year period

BACKGROUND

To assess the safety and effectiveness of the exclusive use of 27-gauge instruments for all vitreoretinal diseases requiring vitrectomy.

METHODS

In this retrospective study, 1020 consecutive surgeries were performed on 958 eyes of 848 patients using 27-gauge instruments from March 2017 to June 2021. Patients with a minimum follow-up of 3 months were included. Surgical case-mix, best-corrected visual acuity (BCVA), intraocular pressure (IOP), intra- and post-operative complications, and surgery times were recorded.

RESULTS

The study patients were followed up for averagely 11 months. Of the 1020 vitrectomies, 958 were primary procedures. Of the 148 retinal detachment (RD) cases, 138 (93%) required a single vitrectomy. Primary macular hole closure was achieved in 143 of 145 (99%) cases. The average surgical times were 55 and 38 min for RD surgeries and for all other indications, respectively. BCVA improved significantly at the final visit (20/49) compared with the pre-operative visit (20/78) (p < 0.01). IOP was similar at the pre-operative (14.8mmHg) and final (14.3mmHg) visits. Complications recorded include transient hypotony in 39 eyes, iatrogenic retinal breaks in 2 eyes, and a vitreous bleed in 1 other eye.

CONCLUSION

This study revealed that 27-gauge vitrectomy instruments can be used for a wide range of indications, with exclusive use in certain settings. The outcomes were similar to other gauges, including for rhegmatogenous retinal detachment, with minimal complications.

The effect of multiple vitrectomies and its indications on intraocular pressure

Background

To assess the relationship between different indications for trans pars plana vitrectomies (PPV’s) and the intraocular pressure (IOP), and the effect of multiple PPV’s on the IOP. We also examined whether there were differences in the number of IOP-lowering medications or surgeries before and after PPV.

Methods

A retrospective study including all patients that underwent at least one PPV in the period from 2001 till 2014 at our clinic. Medical records of all patients were reviewed and clinically relevant data were entered in a database. Generalized estimating equations models for repeated measurements were used to examine the effect of the number of PPV’s on the IOP and on the risk of undergoing glaucoma surgery, for each of the indications for PPV.

Results

Of 1072 PPV’s 447 eyes fulfilled the inclusion criteria. The IOP increased with 3.0 mmHg after a PPV with indication retinal detachment (p < 0.001), but remained stable after PPV for epiretinal membrane (p = 0.555), macular hole (p = 0.695), and vitreous hemorrhage (p = 0.787). At the end of the follow-up period the number of IOP-lowering medications was significantly higher compared to baseline, except in the macular hole group (p = 0.103). Also, the number of eyes that underwent glaucoma surgery was significantly higher compared to the fellow (not-operated) eyes (p < 0.001). There was a significant association between the number of PPV’s and the final IOP for the indication retinal detachment (p = 0.009), and between the number of PPV’s and glaucoma surgery (odds ratio [95% confidence interval]: 2.60 [1.62–4.15]).

Conclusions

The IOP rises significantly after PPV with indication retinal detachment. This association was not found for other indications for PPV. Also, the risk of IOP-lowering surgeries was higher after PPV, but not different between the PPV indications. The IOP should be monitored carefully after PPV, since there may be a higher risk of secondary glaucoma.

Primary vitrectomy for rhegmatogenous retinal detachment in pseudophakic eyes: 20-gauge versus 25-gauge vitrectomy

PURPOSE

To report anatomical and functional outcome of 20-gauge versus 25-gauge primary pars plana vitrectomy for management of complex rhegmatogenous retinal detachment in pseudophakic eyes.

METHODS

Prospective single-centre randomized comparative pilot trial. Fifty patients with retinal detachment (RD) not complicated by proliferative vitreoretinopathy grade B or C, who cannot be treated with a single meridional sponge, were randomized (1:1) from November 2006 to January 2010 to either 20-gauge or 25-gauge vitrectomy as first surgical intervention and followed up over a 12-month period, evaluating change in best-corrected visual acuity, anatomical success and intraocular pressure dysregulation.

RESULTS

Mean visual acuity improved by 0.88 (SD 0.67) from 1.22 logMAR (SD 0.63) to 0.34 logMAR (SD 0.31) in the 20-gauge group and by 0.53 (SD 0.91) from 0.86 logMAR (SD 0.73) to 0.34 logMAR (SD 0.46) in the 25-gauge group. Final anatomical success rate was 100% and primary success rate was 69% at 6 months of follow-up. In the 20-gauge group, the retina was attached after one single procedure in 18 eyes (72%) and in 21 eyes (84%) of the 25-gauge group. Two patients in the 25-gauge group had hypotony at the first postoperative day which normalized within 6 weeks.

CONCLUSION

In our series, transconjunctival sutureless 25-gauge and 20-gauge vitrectomy showed comparable results in pseudophakic RD not suitable for single sponge surgery with respect to visual outcome and retinal reattachment. Postoperative hypotony does not seem to be a significant problem of transconjunctival sutureless vitrectomy.

Changes in day 1 post-operative intraocular pressure following sutureless 23-gauge and conventional 20-gauge pars plana vitrectomy

Background/Aims:

The benefits associated with transconjunctival sutureless vitrectomy techniques are continuing to be defined. The purpose of this study was to compare the incidence of extreme changes in day 1 intraocular pressure (IOP) following 23-gauge sutureless vitrectomy compared with conventional 20-gauge vitrectomy.

Methods:

Fifty consecutive 23-gauge and 50 consecutive 20-gauge cases were included; eyes with a history of previous vitreoretinal surgery were excluded. 23-gauge surgery was completed with passive fluid air exchange where no long acting tamponade was indicated. The surgery remained sutureless unless a leak was visible at the end of the procedure. Data were collected by retrospective case note review. Statistical analysis was carried out using Fisher’s exact and chi-square tests.

Results:

Twenty-two percent (11/50) of 23-gauge vitrectomies required suturing of one or more ports. On the first post-operative day hypotony (IOP<5mmHg) occurred in 1/50 eyes in the 20- and 23-gauge groups. Raised pressure (IOP>21mmHg) occurred in 30% (15/50) of eyes in the 20-gauge group and 8% (4/50) of eyes in the 23-gauge group; IOP>30mmHg only occurred in the 20-gauge group (3/50).

Conclusion:

Fluid air exchange following 23-gauge vitrectomy is associated with very low risk of day 1 hypotony. This predominantly sutureless technique appears to reduce the incidence and magnitude of early post-operative IOP elevation compared with conventional 20-gauge vitrectomy.

Comparison of 23-gauge sutureless sclerotomy architecture and clinical outcomes in macular and non-macular surgery using spectral-domain optical coherence tomography

PURPOSE

To compare the 23-gauge (23-G) sutureless vitrectomy incision architecture in macular and non-macular surgery, using anterior segment spectral-domain optical coherence tomography (SD-OCT), and to evaluated its influence on clinical outcomes.

METHODS

A prospective, observational case series of 43 patients who underwent primary transconjunctival 23-G pars plana vitrectomy (PPV) for macular and non-macular diseases. All sclerotomy wounds were imaged 1 day after surgery using the anterior segment module of SD-OCT (OCT Spectralis; Heidelberg Engineering, Heidelberg, Germany). Sclerotomy architecture, including good wound apposition, presence of gaping and misalignment of the roof and floor of the incisions were evaluated. Preoperative, intraoperative and postoperative medical record data were also prospectively collected.

RESULTS

  Incision gaping and misalignment of the roof and floor occurred more frequently in the superotemporal and superonasal quadrants than in the inferotemporal quadrant (p < 0.05) and was more frequent in the non-macular group than in the macular group (p < 0.05). The incidence of incision gaping increased significantly as the incision angle increased. In the macular group, the mean postoperative intraocular pressure (IOP) did not change from the preoperative value, whereas in the non-macular group, the mean IOP decreased significantly from 15.09 ± 2.58 mmHg preoperatively to 12.18 ± 3.25 mmHg on the first postoperative day (p < 0.005). The mean IOP did not differ significantly between the two groups of surgery at 1 week, and at 1 month postoperatively.

CONCLUSIONS

  In 23-G PPV, non-macular surgery is associated with a significant postoperative IOP decrease in comparison with macular surgery, which could be explained by the most remodelled wound architecture.

Intraocular pressure changes following 20G pars-plana vitrectomy

PURPOSE

To observe the excursions of short-term intraocular pressure (IOP) after 20-G pars-plana vitrectomy (ppV).

MATERIAL AND METHODS

In a prospective study, 851 patients (age: mean 63 ± 15 years) underwent unilateral ppV for various vitreoretinal diseases using different endotamponades [Balanced Salt Solution (BSS) 33.1%, Air 7.2%, SF(6) 33.6%, silicon oil 5000 cst 26.1%]. Intraocular pressure was measured in all patients before and at 3, 6, 24 and 48 hr after surgery. Survival analysis was performed to determine the cumulative hazard of IOP changes depending on endotamponade and time point after ppV (Log-Rang - Mantel Cox; p < 0.0001).

RESULTS

  At baseline, IOP ranged from 0 to 50 mmHg (mean IOP: 15.3 ± 5.3 mmHg). Mean IOP after surgery revealed a slight elevation (3 hr: 16.5 ± 11.0 mmHg; 6 hr 16.9 ± 9.8 mmHg; 24 hr 19.7 ± 8.0 mmHg; 48 hr 17.3 ± 6.2 mmHg; range: 0-64 mmHg). Silicon oil filling revealed highest mean values at already 3 hr after surgery (21.8 mmHg). Also, BSS filling showed a peak after 3 hr; however, mean values were lower. Equivalent high IOP values as for silicon oil tamponade were found for gas filling; however, maximal peak was reached after 24 hr but not after 3 hr post-treatment. The cumulative hazard in all patients to reach IOP ≥ 30 mmHg after 24 hr was 23.9%; (IOP ≥ 40 mmHg = 8.2%). Herein, oil filling revealed highest risk at all time points after surgery. The risk of suffering from IOP < 5 mmHg lasting longer than 6 hr was only 1.2% after 20 G vitrectomy.

CONCLUSION

Intraocular pressure measurements after ppV are important to prevent unintentional high IOP, especially within the early phase (3 hr post-treatment) in eyes with silicon oil filling. Gas filling leads to prolonged IOP increase (24 hr post-treatment). Long-lasting hypotony (≥ 6 hr) is very rare after 20G vitrectomy.

Clinical presentation of a mixed 23-gauge infusion and 20-gauge pars plana technique for active silicone oil removal

AIM

To present with a clinical case series of a mixed 23-gauge infusion and 20-gauge pars plana technique for 5,700-centipoise silicone oil removal (SOR), and to discuss its efficacy and safety.

METHODS

This is a retrospective, non-randomized controlled study. We performed SOR with 23-gauge infusion and 20-gauge active suction technique on 29 patients 29 eyes from April to October, 2011 (mixed group). During the surgeries, a 23-gauge sclerotomy was made for infusion and a 20-gauge sclerotomy was used for active silicone oil suction. Anterior segment optical coherence tomography (OCT) was applied for 23-gauge sclerotomy analysis 1 day post-operation. Traditional 20-gauge SOR was performed on another consecutive 29 patients 29 eyes, the control group (20G group).

RESULTS

There were 2 eyes (6.9%) in mixed group and 5 eyes (17.2%) in 20G group which had recurrent retinal detachment after surgery. Hopytony (IOP≤6mmHg) occurred in 8 eyes (27.6%) of mixed group and in 10 eyes (34.5%) of 20G group post-operation, but all of them recovered to the normal level finally. There were no statistical significant differences. Final visual acuity was significantly increased after surgery in both groups. Anterior segment OCT images were acquired from 13 eyes of mixed group, and all of them had a proper wound apposition. But local ciliary detachment was found in 9 eyes (69%). It was hard to define the OCT image of the sclerotomies and ciliary body because of the serious conjunctival hemorrhages and chemosis in 20G group.

CONCLUSION

This mixed technique is a convenient and effective way to remove high viscosity silicone oil. Compared with traditional 20-gauge SOR, it does not increase the risk of post-operative complications and has less conjunctival reactions.. Transient postoperative hypotony is common for this procedure and subclinical ciliochoroidal detachment is a probable cause.

Primary 23-gauge vitreoretinal surgery for rhegmatogenous retinal detachment

AIM

To report the effectiveness and safety of primary 23-Gauge (G) vitreoretinal surgery for rhegmatogenous retinal detachment (RRD).

METHODS

In this retrospective study, 49 eyes of 49 consecutive patients who underwent primary 23-G transconjunctival sutureless vitrectomy (TSV) for RRD between January 2007 and July 2009 at our institution were evaluated.

RESULTS

Mean follow-up time was 8.9±7.7 months (1-28 months). Retinal reattachment was achieved with a single operation in 47(95.9%) of 49 eyes. In two eyes (4.1%), retinal redetachment due to new breaks was successfully treated with reoperation using the 23-G TSV system. Mean logMAR visual acuity was 2.01±0.47 preoperatively and 1.3±0.5 postoperatively (P<0.001, Paired t-test). Mean preoperative intraocular pressure (IOP) was 14.1±2.8mmHg. Mean postoperative IOP was 12.3±3.6mmHg at 1 day, 13.1±2.1mmHg at 1 week, 14.3±2.2mmHg at 1 month. Iatrogenic peripheral retinal break was observed in 1 eye (2.0%) intraoperatively. No sutures were required to close the scleral or conjunctival openings, and no eyes required convertion of surgery to 20-G vitrectomy.

CONCLUSION

Primary 23-G TSV system was observed to be effective and safe in the treatment of RRD.

Comparison of postoperative intraocular pressure changes between 23-gauge transconjunctival sutureless vitrectomy and conventional 20-gauge vitrectomy

PURPOSE

To compare the intraocular pressure (IOP) after 23-gauge transconjunctival sutureless vitrectomy (TSV) and conventional 20-gauge vitrectomy for various vitreoretinal diseases.

METHODS

This was a retrospective interventional case series including 338 cases of 23-gauge TSV and 476 cases of 20-gauge vitrectomy with minimum follow-up period of 1 month. Postoperative 1 day, 1 week and 1 month IOPs were compared. Multiple regression analysis to assess the actual effect of gauge of vitrectomy on postoperative IOP was performed including intraoperative and postoperative factors influencing postoperative IOP as covariates.

RESULTS

The mean IOP of 20-gauge vitrectomy was significantly higher than that of 23-gauge TSV (20.6 ± 8.02 mm Hg vs 12.8 ± 4.48 mm Hg, P<0.001) at postoperative day 1, but the differences were not significant at postoperative 1 week and 1 month. The IOP pattern of 23-gauge TSV demonstrated more stable course than that of 20-gauge vitrectomy. At 1 day post vitrectomy, the incidence of hypertony was higher in 20-gauge, whereas that of hypotony was higher in 23-gauge. Among risk factors, the 20-gauge vitrectomy showed the strongest association with postoperative 1 day IOP rise.

CONCLUSION

Twenty-three-gauge TSV has stable and lower IOP in the early postoperative period than the 20-gauge vitrectomy. In patients whose retina and optic nerves are vulnerable to higher or fluctuating IOP, 23-gauge TSV may be more beneficial.

Study of intraocular pressure after 23-gauge and 25-gauge pars plana vitrectomy randomized to fluid versus air fill

PURPOSE

To determine if a difference in intraocular pressure (IOP) exists after small-gauge pars plana vitrectomy randomized to fluid versus 80% sterile air fill.

METHODS

Ninety-two eyes undergoing 23-gauge and 25-gauge transconjunctival pars plana vitrectomy were randomized to fluid versus air fill, and IOP was measured at 5 different time points.

RESULTS

There is no difference in the mean IOP for eyes undergoing small-gauge pars plana vitrectomy randomized to fluid versus air fill after vitrectomy. Using 23-gauge instrumentation, the mean immediate and 2-hour postoperative IOPs were statistically lower than the mean preoperative IOP. The mean Postoperative Day 1 and Week 1 IOPs were statistically higher than the mean immediate postoperative IOP. Using 25-gauge instrumentation, the mean IOP was not statistically different at any time points in the 2 groups. When comparing 23-gauge with 25-gauge instrumentation, the immediate postoperative IOP was statistically lower and the rate of suture closure for sclerotomies was higher for 23-gauge vitrectomy.

CONCLUSION

When performing 23-gauge or 25-gauge pars plana vitrectomy, there was no difference in mean IOP for fluid- versus air-filled eyes. However, the mean IOP in the immediate postoperative period was statistically lower, and there was a higher rate of suture closure for 23-gauge compared with 25-gauge instrumentation.

Advantages and limitations of small gauge vitrectomy

Small gauge vitrectomy utilizing 23- and 25-gauge instrumentation has definite advantages, but also limitations, due to the physics of smaller instruments and sutureless surgery. Higher infusion and aspiration pressures are needed to remove the vitreous using 23- and 25-gauge probes. The advantages include decreased surgical times, less tissue manipulation, reduced inflammation and pain postoperatively with more rapid visual recovery. A disadvantage is greater instrument flexion than 20-gauge probes, making small gauge vitrectomy more appropriate for indications such as vitreous opacities, epiretinal membranes, macular holes, and simple retinal detachments. There are also some increased complications related to small gauge vitrectomy, including dislocation of cannulas intraoperatively, early postoperative hypotony, choroidal detachment, and possibly an increased risk of infectious endophthalmitis.