Comparative study of straight vs angled incision in 27-gauge vitrectomy for epiretinal membrane

Selective ILM Staining and Safety of Two Vital Dyes During a Human-Like Pars Plana Vitrectomy Ex Vivo in Porcine Eyes

PURPOSE

An ideal dye for intraocular use should effectively stain the target tissue while being easy to apply and remove. Additionally, it should not have any adverse effects resulting from prolonged contact with the retinal tissue. Recently, concerns have been raised about the safety of some vital dyes during surgical procedures as they may cross the internal limiting membrane and deposit on the retina. In this study, we aimed to investigate whether commercially available vital dyes, VIEW-ILM® and TWIN® (AL.CHI.MI.A. S.r.l., Ponte San Nicolò, Padova, Italy), have the potential to cross the internal limiting membrane during vitreoretinal surgery and deposit on the retina. Furthermore, we evaluated their safety in vitro and in vivo.

METHODS

A human-like pars plana vitrectomy was performed on porcine eyes ex vivo, with VIEW-ILM® or TWIN® used to stain the internal limiting membrane either with or without subsequent internal limiting membrane peeling. The two dyes were then extracted from retinal punches with or without internal limiting membrane, and quantified using high performance liquid chromatography. Safety was evaluated through in vitro cytotoxicity tests and in vivo skin sensitization and irritation tests according to ISO standards.

RESULTS

High performance liquid chromatography analyses demonstrated that VIEW-ILM® and TWIN® effectively stained the internal limiting membrane without crossing the membrane. No residual dyes were found in the retinal layers after internal limiting membrane removal. Furthermore, both in vitro and in vivo safety tests confirmed the absence of cytotoxicity, skin sensitization, and irritation.

CONCLUSION

The results of this study support the safety and efficacy of VIEW-ILM® and TWIN® for internal limiting membrane staining. The experimental protocol described in this study could be utilized to gain a comprehensive understanding of the characteristics of vital dyes.

A Prospective Randomized Study Comparing 27-Gauge Vitrectomy to 23-Gauge Vitrectomy for Epiretinal Membranes and Full-Thickness Macular Holes

Purpose

To compare the surgical and clinical outcomes of 27-gauge vitrectomy and 23-gauge vitrectomy.

Methods

We conducted a single-center, prospective, randomized study. Fifty-three patients affected by vitreoretinal interface disorders (epiretinal membranes and macular holes) were randomly scheduled to undergo 27-gauge (28 patients) or 23-gauge (25 patients) pars plana vitrectomy. The presence of any potential factor of increased baseline inflammation or eye anatomy influencing the surgery was criteria for exclusion. The time of surgery, postoperative intraocular pressure (IOP), state of sclerotomy wounds, rate of complications, postoperative pain, and indicators of inflammation were studied. We also introduced a new parameter to compare intraocular inflammation after surgery, given by the change in the number of intraretinal hyperreflective foci (HRF).

Results

The 27-gauge vitrectomy was 1.28 min longer than 23-gauge vitrectomy (P < 0.05). The day after surgery, the mean IOP value was significantly higher in the 27-gauge group (16.12 mmHg versus 13.04 mmHg in the 23-gauge group,P < 0.05), but this difference disappeared in successive follow-ups and the sclerotomy wounds closed after 2 weeks in the both groups. The rate of postoperative hypotony did not significantly differ in the two groups (10.71% in the 27-gauge group and 8% in the 23-gauge group the day after the surgery,P = 0.94). Less postoperative eye redness was seen in 27-gauge eyes (value 1 on the scale) compared to 23-gauge (value 2 on the scale) (P < 0.05), but there was no significant difference in intraocular inflammation (cells, Tyndall, and number of HRF,P > 0.05 for all).

Conclusions

The 27-gauge vitrectomy may have better outcomes in terms of IOP maintenance and cause less redness after the surgery but with a slightly prolonged surgery time and no other differences under other parameters (inflammation, rate of complications, postoperative pain, visual gain, and closure of the sclerotomy wounds).

27-gauge trocar-assisted sutureless intraocular lens fixation

Backgrounds

However there have been numerous investigations of intrascleral intraocular lens (IOL) fixation techniques, there is room for improvement in terms of simplifying complicated techniques and reducing the high levels of skill required. This study aimed to report a novel technique for sutureless intrascleral fixation of the IOL using retinal forceps with a 27-gauge trocar.

Methods

Nineteen eyes of 18 patients underwent intrascleral fixation of the IOL from July 2018 to September 2019 were enrolled in this study. A 27-gauge trocar formed 3-mm scleral tunnels positioned at 4 and 10 o’clock, 2 mm from the corneal limbus. We used a 3-piece IOL haptic grasped by a 27-gauge retinal forceps and pulled from the 27-gauge trocar. The IOL was fixed by making a flange. Main outcome measures were visual acuity, corneal endothelial cell density, IOL tilt, decentration, predicted error of refraction and complications.

Results

The 19 eyes were followed up for 1 month. The mean pre- and postoperative logMAR uncorrected visual acuity (UCVA) was 1.06 ± 0.63 and 0.40 ± 0.26, respectively (p < 0.01), while the mean pre- and postoperative logMAR best corrected visual acuity (BCVA) was 0.27 ± 0.51 and 0.06 ± 0.15, respectively (p = 0.09). The mean corneal endothelial cell density was 2406 ± 625 to 2004 ± 759 cells/mm² at 1 month (p = 0.13). The mean IOL tilt was 3.52 ± 3.00°, and the mean IOL decentration was 0.39 ± 0.39 mm. There was no correlation among IOL tilt, decentration and BCVA (p > 0.05). The mean prediction error of the target refraction was − 0.03 ± 0.93 D. The complications were vitreous hemorrhage (3 eyes), hyphema (1 eye), IOP elevation (1 eye), iris capture of the IOL (1 eye) and hypotony (2 eyes). No IOL dislocation occurred.

Conclusions

IOL intrascleral fixation with a flange achieved good IOL fixation and visual outcome in the scleral tunnels created with the 27-gauge trocar.

Multicenter survey of sutureless 27-gauge vitrectomy for primary rhegmatogenous retinal detachment: a consecutive series of 410 cases

PURPOSE

To evaluate the surgical outcomes of the 27-gauge (G) vitrectomy system for the treatment of primary rhegmatogenous retinal detachment (RRD).

METHODS

This retrospective consecutive series multicenter study involved a total of 410 eyes of 406 patients who underwent 3-port transconjunctival 27G pars plana vitrectomy (PPV) for RRD between November 2014 and December 2016 and who were followed for a minimum of 3 months postoperative. The main outcome measure was primary reattachment, with the secondary outcome measures being final reattachment, improvement of visual acuity (VA), intraocular pressure (IOP), intraoperative and postoperative complications, and surgery time.

RESULTS

Of the 410 treated eyes, primary reattachment was achieved in 392 (95.6%) and final reattachment was achieved in 410 (100%). In 226 eyes (55.1%) with macula-on RRD, the mean logarithm of the minimum angle of resolution (logMAR) VA improved from 0.16 ± 0.51 pre-surgery to 0.02 ± 0.14 post-surgery (P = 0.11). In 184 eyes (44.9%) with macula-off RRD, logMAR VA improved from 1.06 ± 0.77 pre-surgery to 0.26 ± 0.35 post-surgery (P < 0.001). Following surgery, the mean IOP was highest at 1 day (15.7 ± 7.0 mmHg) postoperative. In all eyes, surgery was concluded without the use of sutures or the need of conversion to a larger-gauge instrument. Although hypotony was observed in 14 (3.4%) of the 410 treated eyes at 1 day postoperative, it spontaneously resolved within 1 week without additional surgical intervention. No postoperative complications such as infectious endophthalmitis were observed throughout the follow-up period.

CONCLUSION

Our findings show that 27G PPV is both safe and effective for the treatment of primary RRD.