Intraoperative complications of patients undergoing small-gauge and 20-gauge vitrectomy: a database study of 4,274 procedures

Early vitrectomy is indicated for both diffuse and dense vitreous haemorrhages of unknown aetiology

BACKGROUND

Early vitrectomy for complete fundus-obscuring vitreous haemorrhage (VH) allows for prompt diagnosis and treatment of the cause.

AIMS

To analyse the causes of VH of unknown aetiology, whether partially fundus-obscuring or dense, and to determine the outcomes of early vitrectomy.

METHODS

A retrospective review of patients who underwent early vitrectomy within 10 days of symptom-onset for partially fundus-obscuring or dense VH of unknown origin. Patients with evidence of proliferative diabetic retinopathy in either eye or any other preoperatively diagnosed aetiology of VH were excluded.

RESULTS

19 patients were included. Intraoperative diagnoses were: retinal tears without rhegmatogenous retinal detachment (RRD) (53%); peripheral localised RRD (32%); neovascularisation secondary to retinal vein occlusion (11%) and posterior vitreous detachment without a retinal break (5%). Patients with diffuse VH were as likely to have a retinal tear diagnosed as those with dense VH (88% vs 82%, respectively; p = 0.7). Mean VA improved from 1.26 LogMAR to 0.23 LogMAR postoperatively (p = 0.001). 1 patient (5%) developed a RRD one-year postoperatively.

CONCLUSIONS

In cases of diffuse or dense VH of unknown aetiology, an occult retinal tear should be suspected. Early vitrectomy should be strongly considered regardless of whether the fundal view is partially or completely obscured, to prevent progression to visually significant RRDs.

Trocar blade-assisted skewer technique for phacoemulsification of a dislocated lens

A posteriorly dislocated lens is often managed with a fragmatome through a pars plana approach because it is difficult to manage anteriorly. The lens often sinks to the surface of the retina or floats around in the vitreous cavity during pars plana lensectomy. Mechanical trauma can occur while removing the dislocated lens fragments. However, sometimes the lens can be confined to the anterior vitreous cavity even though the zonules are completely disrupted. It would be ideal if there was a simple way to stabilize and support the lens so that the lens could remain in the posterior chamber while phacoemulsification is performed through a corneal incision as usual. We describe a technique using a trocar blade to stabilize the lens while performing phacoemulsification through a corneal incision. We found it to be a useful and safe instrument to support the subluxated lens during phacoemulsification.

Pars Plana Vitrectomy Port Sizes: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND AND OBJECTIVE

The uptake of small-gauge (SG; ie, 23-gauge [23-G], 25-gauge [25-G], and 27-gauge [27-G]) pars plana vitrectomy (PPV) has grown. We aim to investigate the advantages and disadvantages of various PPV port sizes in a meta-analysis of randomized controlled trials (RCTs).

MATERIALS AND METHODS

A systematic literature search was performed for RCTs comparing PPV port sizes for any indication. Weighted mean differences (WMDs) and risk ratios (RRs) were calculated, and meta-analysis was performed with random-effects models.

RESULTS

A total of 1,678 eyes from 22 RCTs were included. Risk-of-bias assessment found some concerns in 13 studies. Compared with 20-gauge PPV, there was no significant difference in the final or change in best-corrected visual acuity (BCVA; five studies analyzed each) relative to that of SG PPV. SG PPV was associated with a significantly greater incidence of hypotony (RR = 3.79; 95% confidence intervals [CI], 2.02 to 7.10; P < .0001; six studies) and choroidal detachment (RR = 5.65; 95% CI, 1.01 to 31.71; P = .05; three studies). Compared with 25-G PPV, there was no significant difference in BCVA at any time point with 23-G (two studies), and significantly more frequent port suturing was required with 23-G (RR = 0.46; 95% CI, 0.25 to 0.84; P = .01; two studies). Compared with 25-G PPV, 27-G was associated with a significantly better final BCVA (WMD = -0.06 logMAR; 95% CI, -0.11 to -0.01; P = .02; five studies) and a significantly lengthened surgery (WMD = 4.11 minutes; 95% CI, 0.18 to 8.05; P = .04; three studies).

CONCLUSIONS

There was no significant difference in visual or surgical outcomes following 20-gauge PPV relative to SG PPV (Grading of Recommendations, Assessment, Development, and Evaluation recommendation: low certainty), and there was an increased risk of postoperative complications with SG PPV (moderate certainty). Compared with 25-G PPV, 23-G required more frequent port suturing (moderate certainty), whereas 27-G may be associated with a better final BCVA but longer surgery (low and moderate certainty, respectively). [Ophthalmic Surg Lasers Imaging Retina. 2022;53:152-158.].

Pars plana vitrectomy in uveitis in the era of microincision vitreous surgery

Pars plana vitrectomy (PPV) in uveitis is indicated for various diagnostic and therapeutic indications. With the advent of microincision vitreous surgery (MIVS), the use of PPV in uveitis has increased with a wider spectrum of indications due to shorter surgical time, less patient discomfort, less conjunctival scarring, and a decreased rate of complications as compared to standard 20G vitrectomy. Because of faster post-operative recovery in terms of visual improvement and reduction of inflammation, and reduced duration of systemic corticosteroids, MIVS has gained popularity in uveitis as an adjunctive therapy to the standard of care medical therapy. The safety and efficacy of MIVS is related to the emerging vitrectomy techniques with better and newer cutters, illuminating probes, and accessory instruments. Because of the instrumentation and fluidics of MIVS, PPV is emerging as a safe and useful alternative for diagnostic challenges in uveitis, aiding in earlier diagnosis and better outcome of inflammatory disease, even in the presence of severe and active inflammation, which was once considered a relative contraindication for performing vitreous surgery. However, for surgical interventions for therapeutic indications and complications of uveitis, it is advisable to achieve an optimum control of inflammation for best results. The increasing reports of the use of MIVS in uveitis have led to its wider acceptance among clinicians practicing uveitis.

INCIDENCE AND RISK FACTORS FOR HYPOTONY AFTER 25-GAUGE PARS PLANA VITRECTOMY WITH NONEXPANSILE ENDOTAMPONADE

PURPOSE

The purpose of this study was to assess the incidence and risk factors for early postoperative hypotony after 25-gauge pars plana vitrectomy with nonexpansile endotamponade.

METHODS

A retrospective study of consecutive patients who underwent 25-G pars plana vitrectomy. Hypotony was defined as an intraocular pressure of 5 mmHg or less after surgery and ocular hypertension as an intraocular pressure greater than 21 mmHg.

RESULTS

Overall, 307 eyes of 307 patients with a mean age of 61.7 ± 14.3 of which 56.7% were males were included. Hypotony was identified in 5.2% of cases (n = 16) at Day 1 and 0.7% (n = 2) at Week 1 with no hypotony-related complications. The hypotony group had a higher number of previous vitreoretinal surgeries (1.5 ± 1.1 vs. 0.4 ± 0.7, P < 0.001) and a higher prevalence of preoperative ocular hypertension (22.2% vs. 4.8%, P = 0.02), pseudophakia (77.8% vs. 48.4%, P = 0.01), silicone oil removal (61.1% vs. 8.3%, P < 0.001), and external diathermy performed (55.6% vs. 20.1%, P = 0.001). In stepwise multivariate analysis, significant parameters were silicone oil removal (R = 16.34%, odds ratio 13.45, P < 0.001), pseudophakia (R = 5.69%, odds ratio 3.65, P = 0.03), and younger age (R = 2.68%, odds ratio 0.96, P = 0.04).

CONCLUSION

Silicone oil removal is a significant risk factor for early postoperative hypotony after 25-G pars plana vitrectomy.

Treatment-Emergent Adverse Events in Gene Therapy Trials for Inherited Retinal Diseases: A Narrative Review

Patient safety is a primary priority in the conduction of retinal gene therapy trials. An understanding of risk factors and mitigation strategies for post-procedure complications is crucial for the optimization of gene therapy clinical trial protocols. In this review, we synthesize the literature on ocular delivery methods, vector platforms, and treatment-emergent adverse effects in recent gene therapy clinical trials for inherited retinal diseases.

Subthreshold micropulse yellow laser for the management of refractory cystoid macular edema consequent to complicated cataract surgery

PURPOSE

To report the safety and efficacy of subthreshold micropulse yellow laser of 577 nm for a complex case of refractory pseudophakic cystoid macular edema.

METHODS

A retrospective chart review of an interventional case report of three subthreshold micropulse yellow laser interventions for refractory pseudophakic cystoid macular edema.

PATIENT

A 77-year-old healthy female underwent pseudoexfoliative cataract surgery complicated by posterior capsule rupture and sulcus intraocular lens implantation. After 3 months, she required a scleral fixation of the same lens, due to a lack of capsular support and decentration of the intraocular lens. One month later, she experienced a severe pseudophakic cystoid macular edema (foveal thickness of 399 µm and best-corrected visual acuity of 20/80 Snellen). The condition was refractory to conventional treatments prior to subthreshold micropulse yellow laser interventions, including non-steroidal anti-inflammatory eye drops, topical steroids, oral indomethacin and three sub-Tenon's triamcinolone injections, attempted over a 14-month period.

RESULTS

Subthreshold micropulse yellow laser treatment was performed and immediate resolution was achieved and maintained for 2 months. Two cases of edema relapse were observed at 3 months from initial laser treatment and again at 4 months from the second laser treatment. Final patient's follow-up at 6 months from the third laser treatment evidenced the absence of edema, improved visual acuity (foveal thickness of 265 µm/best-corrected visual acuity of 20/30 Snellen) and the absence of complications.

CONCLUSIONS

Subthreshold micropulse yellow laser seems to be a safe and effective treatment for short-term resolution of refractory pseudophakic cystoid macular edema after complicated cataract surgery and represents a useful alternative to expensive and invasive therapies. A trend towards a longer duration of edema resolution with every subthreshold micropulse yellow laser repetition was observed.

The Role of Subthreshold Micropulse Yellow Laser as an Alternative Option for the Treatment of Refractory Postoperative Cystoid Macular Edema

BACKGROUND

To evaluate the efficacy and the safety of subthreshold micropulse yellow laser (SMYL) in the treatment of chronic postoperative cystoid macular edema (PCME), which is refractory to standard therapies.

METHODS

A retrospective chart review of ten eyes of ten patients affected by refractory PCME who underwent SMYL was performed. Five PCME cases were subsequent to uncomplicated cataract surgery (CS), two cases to complicated CS (CCS) with posterior capsule rupture and three cases occurred after retinal detachment surgery (RD). All conditions were refractory to conventional treatments prior to SMYL interventions for at least 4 months, including nonsteroidal anti-inflammatory eyedrops, topical steroids, oral indomethacin, sub-Tenon's triamcinolone injections and Dexamethasone intravitreal implants. All patients underwent one or more treatments with 577 nm SMYL photo-stimulation, with 7 × 7 grids with confluent spots and a 5% duty cycle covering the whole edematous retina, including the foveal center. Best corrected visual acuity (BCVA) and central macular thickness (CMT) were obtained using OCT, and evaluated before and after the treatment at 1, 2, 3 and 6-month follow-ups.

RESULTS

A complete subfoveal macular edema resolution was observed in all of the eyes, with statistically significant improvements in terms of BCVA and CMT in all of the follow-up timelines (at 6 months, p = 0.002 and p = 0.005, respectively). The mean number of laser treatments was 1.3. At the final follow-up, a complete subfoveal edema reabsorption was observed in all patients with visual acuity improvement. No complications were observed in any case.

CONCLUSIONS

SMYL seems to be a safe and effective treatment for the long-term resolution of refractory PCME and may be a useful alternative to expensive and invasive therapeutic options.

Prophylactic Circumferential Laser Retinopexy in Macular Hole and Epiretinal Membrane Surgeries

Background:

The role of PCLR in vitrectomy surgeries for macular diseases is controversial. Several studies report a reduction in post-operative RD rates, while other studies do not show such reduction. reducing complications stemming from intra- and post- operative retinal tears, especially at sclerotomy sites, are suggested as reasons for PCLR use.

Objective:

To investigate the effect of PCLR on the rate of post-operative RD in patients undergoing pars plana vitrectomy for either Macular Hole (MH) or epiretinal membrane (ERM).

Methods:

This retrospective study included 179 eyes of 170 patients who underwent vitrectomy for either MH or ERM between 2006-2012. Recorded parameters included demographic information, diagnosis, lens status, use and type of tamponade, whether PCLR was performed, follow-up period, the occurrence of RD, the cause and time of RD. Outcome and complication rates were compared between patients who received PCLR (PCLR group) and those who did not (Control group).

Results:

The study included 179 eyes of 170 patients. 126 eyes had PCLR while 53 eyes did not. Pre-operative demographics data, best-corrected visual acuity, lens status and indication for macular surgery were similar between the two groups. Post-operative RD was diagnosed in one eye (1.8%) in the control group and 5 eyes (3.9%) in the PCLR group (Kaplan-Meier survival analysis, log-rank p = 0.28).

Conclusion:

PCLR was not correlated with a decrease in RD in MH and ERM surgeries in our cohort. Intra-operative and post-operative examination for small retinal breaks is essential in all surgeries. PCLR might be unnecessary in small gauge vitrectomies.

International multi-center study of iatrogenic retinal tears in pars plana vitrectomy

AIM

To study and compare the effect of different surgical settings on the development of iatrogenic retinal tears (IRT) in conventional (20-gauge) and microincisional vitrectomy.

METHODS

An international retrospective comparative study of 394 patients who had simple vitrectomy at three tertiary centers. Surgeries were performed by four retina surgeons using different viewing systems. Two groups of eyes were compared: microincisional vitrectomy (327 eyes) and conventional (67 eyes) vitrectomy. An iatrogenic tear was defined as the occurrence of one or more peripheral retinal tears during surgery or at any visit in the first 6wk postoperatively.

RESULTS

Mean age was 67±12y and 55% were female. Iatrogenic tears occurred in 11/394 (2.8%) of eyes. The rate of tears was similar among different surgeons and viewing systems (P=0.93 and P=0.76, respectively). Surgical indication, preexisting pseudophakia/aphakia, induction of posterior vitreous detachment (PVD) during surgery, and the use triamcinolone acetonide didn't significantly affect the rate of tears (P>0.1 for all factors). A higher rate of tears was found in the conventional group compared to the microincisional group (respectively, 7.5%, 1.8%, P=0.02).

CONCLUSION

The rate of IRT in vitrectomy is not significantly affected by surgical indication, preexisting PVD or pseudophakia, or use of triamcinolone or different viewing systems but is significantly higher in conventional vitrectomy. Microincisional platforms improve the safety of vitrectomy regardless of the viewing system used.

Iatrogenic retinal breaks and postoperative retinal detachments in microincision vitrectomy surgery compared with conventional 20-gauge vitrectomy: a meta-analysis

PURPOSE

To assess the incidence of iatrogenic retinal breaks (IRBs) and postoperative retinal detachments (RDs) in microincision vitrectomy surgery (MIVS) compared with 20-gauge (20 G) vitrectomy.

METHODS

A comprehensive literature search was performed to find relevant studies and a meta-analysis of the IRBs and postoperative RDs rates after 20 G vitrectomy versus MIVS was conducted.

RESULTS

Thirty-two studies were selected, including 14,373 eyes (6932 eyes in the 20 G group, 7441 eyes in the MIVS group). The meta-analysis demonstrated that the incidence of IRBs was significantly higher in 20 G vitrectomy vs. MIVS (OR = 2.22, 95% CI, 1.93-2.57, P < 0.00001) and in a subanalysis vs. 23 G MIVS (OR = 2.19, 95% CI, 1.87-2.56, P < 0.00001) and vs. 25 G MIVS (OR = 2.27, 95% CI, 1.62-3.18, P < 0.00001). Similar result was obtained in a subanalysis for macular surgery (OR = 2.44, 95% CI, 1.99-2.99, P < 0.00001), and also for sclerotomy-related IRBs (OR = 3.73, 95% CI, 2.55-5.44, P < 0.00001), but not for surgically induced posterior vitreous detachment-related IRBs (OR = 1.59, 95% CI, 0.89-2.84, P = 0.12). The incidence of postoperative RDs in 20 G vitrectomy was significantly higher compared to MIVS (OR = 1.72, 95% CI, 1.21-2.46, P = 0.003) and in a subanalysis vs. 23 G MIVS (OR = 2.45, 95% CI, 1.50-4.00, P = 0.0003), but not for 25 G MIVS (OR = 1.01, 95% CI, 0.63-1.64, P = 0.96). Similar result was obtained in a subanalysis for macular surgery (OR = 1.89, 95% CI, 1.26-2.85, P = 0.002).

CONCLUSION

This meta-analysis demonstrated that MIVS is associated with a lower risk of IRBs and postoperative RDs compared to 20 G vitrectomy.

Influence of Surgical Procedures and Instruments on the Incidence of Suprachoroidal Hemorrhage during 25-gauge Pars Plana Vitrectomy

PURPOSE

To evaluate the influence of surgical procedures and instruments that are associated with intraocular pressure (IOP) fluctuations on the incidence of suprachoroidal hemorrhage (SCH) during 25-gauge pars plana vitrectomy (25G-PPV), and to investigate the clinical features of SCH during 25G-PPV.

DESIGN

Retrospective, comparative case series.

PARTICIPANTS

A total of 3034 cases that underwent initial 25G-PPV at a single surgical center.

METHODS

Univariate analysis was performed to evaluate the relationships between the incidence of SCH during 25G-PPV and the surgical procedures and instruments that were associated with IOP fluctuations. The participants were divided into 4 groups that underwent the following procedures: neither fluid-air exchange nor vitreous shaving under scleral depression (group 1, n = 1144); fluid-air exchange alone (group 2, n = 463); vitreous shaving under scleral depression alone (group 3, n = 639); and both procedures (group 4, n = 788). The incidence of SCH in each group was compared. The clinical features and surgical outcomes of SCH during 25G-PPV were also investigated.

MAIN OUTCOME MEASURES

The incidence of SCH during 25G-PPV and the clinical features and surgical outcomes of SCH during 25G-PPV.

RESULTS

The incidence of SCH was significantly higher in cases that underwent fluid-air exchange (P = 0.0047) or vitreous shaving under scleral depression (P = 0.0157). There were no significant relationships between the incidence of SCH and the use of surgical instruments. The incidence of SCH in group 4 (8/788, 1.02%) was significantly higher than that in groups 1 (1/1144, 0.09%), 2 (0/463, 0%), and 3 (0/639, 0%) (P = 0.01). Almost all SCH cases were localized, and there were no cases of SCH involving the posterior pole. Of all the SCH cases, only one case required reoperation for retinal redetachment. No cases required secondary surgical management for SCH.

CONCLUSIONS

There remains a slight risk of SCH during 25G-PPV in cases that require both fluid-air exchange and vitreous shaving under scleral depression. Even if SCH occurs during 25G-PPV, the surgical outcomes after SCH may not be substantially worse.

Assessment of diagnostic and therapeutic vitrectomy for vitreous opacity associated with uveitis with various etiologies

Vitreous opacity (VO) is a common feature of intermediate uveitis, posterior uveitis, and panuveitis. Fundus observation is critical for determining the etiology of uveitis, however, is often interfered with VO. In these clinical settings, vitrectomy contributes to a correct diagnosis and guides alternative management strategies. The purpose of this study was to evaluate the diagnostic yield and surgical outcome of vitrectomy in uveitic patients with VO and compare the visual outcome between infectious and noninfectious uveitis. Forty-five eyes with uveitis-associated VO underwent diagnostic and therapeutic vitrectomy, and etiological diagnosis of uveitis was confirmed in 34 of 45 eyes (75.6%). The diagnoses were infectious uveitis in 13 eyes (28.9%), noninfectious uveitis in 21 eyes (46.7%), and unidentified uveitis in 11 eyes (24.4%). Visual acuity (VA) improvement rates at 6 months after surgery were 69.2%, 76.2%, and 90.9% in the infectious, noninfectious, and unidentified uveitis groups, with no significant difference among 3 groups. Significant decrease in inflammation score after vitrectomy was observed only in the infectious uveitis group. This study demonstrated that diagnostic vitrectomy for inflammatory eyes with VO of unknown etiology was effective in infectious and noninfectious uveitis, and the therapeutic effect of VA improvement was observed in both types of uveitis.