Viscoelastic substance in prefilled syringe as an etiology of Toxic Anterior Segment Syndrome

Safety and effectiveness comparison of a new cohesive ophthalmic viscosurgical device

PURPOSE

To evaluate the safety and effectiveness of a new cohesive ophthalmic viscosurgical device (OVD) (StableVisc) compared with a marketed cohesive OVD (ProVisc) in patients undergoing cataract surgery.

SETTING

22 sites in the United States.

DESIGN

Prospective multicenter controlled double-masked and randomized 1:1 (StableVisc:ProVisc; stratified by site, age group, and cataract severity).

METHODS

Adults (≥45 years) with age-related noncomplicated cataract considered amenable to treatment with standard phacoemulsification cataract extraction and intraocular lens implantation were included. Patients were randomized to receive either StableVisc or ProVisc during standard cataract surgery. Postoperative visits occurred at 6 hours, 24 hours, 7 days, 1 month, and 3 months. The primary effectiveness outcome was the change in endothelial cell density (ECD) from baseline to 3 months. The primary safety endpoint was the proportion of patients who experienced at least 1 intraocular pressure (IOP) measurement ≥30 mm Hg at any follow-up visit. Noninferiority between the devices was tested. Inflammation and adverse events were evaluated.

RESULTS

390 patients were randomized; 187 patients with StableVisc and 193 patients with ProVisc completed the study. StableVisc was noninferior to ProVisc in mean ECD loss from baseline to 3 months (17.5% and 16.9%, respectively). StableVisc was noninferior to ProVisc in the proportion of patients with postoperative IOP ≥30 mm Hg at any follow-up visit (5.2% and 8.2%, respectively).

CONCLUSIONS

The StableVisc cohesive OVD, which provides both mechanical and chemical protection, was safe and effective when used in cataract surgery and provides surgeons with a new cohesive OVD.

The safety and efficacy of phacoemulsification surgery in uncomplicated cataracts with and without an ophthalmic-viscosurgical-device

PURPOSE

To compare and evaluate the results of phacoemulsification surgery involving and not involving an ophthalmic-viscosurgical-device (OVD).

METHODS

A prospective, randomized controlled trial included 60 eyes of 60 patients scheduled to receive phacoemulsification surgery. In order of presentation, patients were randomized into two groups to undergo different surgical techniques: the OVD-free group (n = 30) and the OVD group (n = 30). Each patient's operating time, total ultrasonography (U/S) time, cumulative dissipated energy (CDE), aspiration time, and volume of balanced salt solution (BSS) aspirated were recorded. At 1 day, 1 week, and 1 and 3 months postoperation, measurements of endothelial cell density (ECD) and intraocular pressure (IOP), were taken and compared between the groups.

RESULTS

Total U/S time (p = .567) and CDE (p = .168) were similar between the groups. In the OVD group, operating time (p = .011), aspiration time (p < .001), and volume of BSS aspirated (p < .001) were greater than in the OVD-free group. The change in ECD between the groups was not statistically significant at all visits (p = .433, p = .147, p = .379, p = .534; respectively). Although IOP increased in the OVD group at 1 day postoperation (p = .001), no difference emerged between the groups at 3 months postoperation (p = .121).

CONCLUSION

Phacoemulsification surgery without an OVD took less time than with the OVD and caused no significant loss in ECD. Surgeons concerned about elevated IOP following cataract surgery should apply the OVD-free method.

Toxic anterior segment syndrome and Urrets-Zavalia syndrome: Spectrum of the same entity?

PURPOSE

The purpose of the study was to analyze the outcomes of patients with toxic anterior segment syndrome (TASS) and Urrets-Zavalia (UZ) syndrome.

MATERIALS AND METHODS

The records of all patients with TASS and UZ syndrome were studied. Corrected distance visual acuity (CDVA), intraocular pressure (IOP), and the details of surgeries performed were recorded at 1 and 3 months. We studied the changes in CDVA and IOP using repeated-measure ANOVA and paired t -test, respectively.

RESULTS

Four patients (44.4%) developed refractory UZ syndrome, and five (55.6%) patients had TASS. At the end of 3 months of follow-up, all nine patients had concentric rings of iris atrophy and corneal edema. None of the cases had hypopyon or vitritis. Peripheral anterior synechiae (PAS) with secondary glaucoma was present only in cases of UZ syndrome. Among the four cases of UZ syndrome, goniosynechialysis was performed for 2 cases and trabeculectomy for one case. Despite these interventions, IOP could not be controlled. Patients in the TASS group did not exhibit PAS formation, and IOP was normal, but corneal edema and concentric rings of iris atrophy persisted. Descemet's stripping endothelial keratoplasty was performed for all the TASS cases. There was a statistically significant drop in CDVA (P = 0.028) and an increase in IOP (P = 0.029) at 3-month postcataract surgery.

CONCLUSION

TASS and UZ syndrome could result in sight-threatening complications. They may be considered diseases of the same entity as both the conditions were found in the same cluster. TASS could be considered as an abortive attack of UZ syndrome.

Report of a Cluster of Cases of Toxic Anterior-segment Syndrome After Implantation of a Specific Intraocular Lens Model

PURPOSE

To report a cluster of cases of toxic anterior-segment syndrome (TASS) in eyes implanted with a specific foldable acrylic intraocular lens (IOL) model.

DESIGN

Retrospective case series.

METHODS

The medical records were reviewed for 7 eyes of 4 patients diagnosed with TASS after cataract surgery at Shimane University and Matsue Red Cross Hospital between July and November 2020.

RESULTS

Among the 162 eyes implanted with the Lentis Comfort/LS-313 MF15 IOL, acute anterior chamber (AC) inflammation with fibrin formation developed 1-15 days after uneventful surgeries in 7 (4.3%) eyes (cataract surgery alone, n=4 eyes; combined cataract and minimally invasive glaucoma surgery, n=3 eyes). Other than local steroid use, fibrin membrane removal, YAG laser membranotomy, pars plana vitrectomy, and AC washout were performed to treat inflammation and/or secondary angle closure due to pupillary obstruction.

CONCLUSION

We experienced a cluster of TASS cases in eyes implanted with the Lentis Comfort/LS-313 MF15 IOL in a short period of time. To our knowledge, this is the first report of TASS associated with this IOL.

Pars-plana vitrectomy with phacofragmentation for hyperdense cataracts in eyes with severe microcornea and chorio-retinal coloboma: A novel approach

Purpose:

To report the outcomes of pars-plana approach for the management of brunescent cataract in eyes with severe microcornea and associated chorio-retinal coloboma.

Methods:

This was a retrospective, single center, interventional case series performed in a tertiary eyecare center in central Medical records of consecutive cases of microcornea with coloboma who underwent pars-plana vitrectomy with phacofragmentation (PF) between January 2015 and December 2017 were reviewed.

Results:

The study group comprised of 30 eyes of 30 patients, of which 18 (60%) were males and 12 (40%) were females. The mean age of the patients was 41.9 years (range of 17–70 years). The mean corneal diameter was 6.7 mm with a range of 4–8 mm and all the eyes had dense cataract with nuclear sclerosis of grade 4 or more. The mean preoperative visual acuity was 1.97 (+/-0.067) Log MAR and the mean postoperative vision at 1 month was 1.6 (+/-0.39) Log MAR. Postoperatively, 21 patients (70%) gained ambulatory vision. The visual gain in all the patients was maintained over a mean follow-up period of 15.5 months.

Conclusion:

Pars-plana vitrectomy with PF can be considered in eyes with severe microcornea and brunescent cataracts, where cataract surgery through the limbal (anterior) approach is not only difficult but at times impossible due to anatomical restraints.

Postoperative Endophthalmitis and Toxic Anterior Segment Syndrome Prophylaxis: 2020 Update

Improved surgical techniques have led to an increase in the number of outpatient ophthalmic procedures. In spite of decreased surgical times and overall improved outcomes, endophthalmitis remains one of the most severe complications of ophthalmic surgery. Although there are well known risk factors for postoperative endophthalmitis, some prophylaxis strategies remain controversial. A category of noninfectious postoperative inflammation, known as toxic anterior segment syndrome (TASS), is a rare but important complication of cataract surgery. While several worldwide outbreaks of TASS have occurred, it is challenging to identify an etiology in order to reduce the risk of further cases. Endophthalmitis and TASS cannot be prevented completely, but their rates may be decreased through risk reduction strategies supported by peer-reviewed evidence. This review highlights the current evidence in the prevention strategies for postoperative endophthalmitis and TASS.

Toxic anterior segment syndrome: A review

Toxic anterior segment syndrome is a surgical complication characterized by a noninfectious anterior chamber inflammatory reaction having multiple etiologies. The clinical signs (prominent limbus-to-limbus corneal edema, anterior chamber inflammation) and symptoms (decreased visual acuity, discomfort) generally occur within the first 12-48 hours after intraocular surgery. Most patients achieve good clinical and visual outcomes when there is a prompt clinical diagnosis and adequate treatment. We review the literature on toxic anterior segment syndrome, emphasizing its etiology, pathophysiology, and clinical and surgical management, as well as prognosis and sequelae. Our goal is to reduce the frequency of toxic anterior segment syndrome by highlighting the importance of prevention, early recognition, and distinguishing toxic anterior segment syndrome from infectious endophthalmitis.

Toxic anterior segment syndrome following phakic posterior chamber IOL: a rarity

Implantable collamer lenses (ICL) have gained popularity for correction of myopia where kerato-refractive procedures are not indicated as in cases of high myopic refractive errors. Toxic anterior segment syndrome (TASS) is a very uncommonly reported postoperative complication following ICL implantation. A young patient developed severe corneal oedema and anterior segment inflammation on the first day after ICL implantation. Analysing retrospectively, possible idiosyncratic response to intracameral pilocarpine was considered as a cause for TASS. Prompt and intensive therapy with oral and topical potent steroids was visually rewarding. TASS, though a sterile inflammation can have catastrophic sequelae such as corneal decompensation and secondary glaucoma. Hence, timely identification and management is important.

Toxic anterior segment syndrome-an updated review

Background

Toxic anterior segment syndrome (TASS) can be a rare complication of anterior segment surgery. Here we reviewed the most recent advances in the understanding of TASS.

Methods

English articles related to TASS were retrieved from “PubMed” using the following keywords; “toxic anterior segment syndrome” or “TASS”. The authors of this paper reviewed all the retrieved literature and critical findings were summarized.

Results

The onset of TASS can vary from hours to months. The clinical manifestations are also variable. The causes of TASS are broad and continue to expand and could not be elucidated in over half of the reported cases. Prompt and thorough investigation to explore the causes of TASS is critical. Surgeons should be fully aware and updated regarding possible etiologies and make ceaseless efforts to prevent TASS. This effort begins with establishing TASS prevention protocols and regularly training surgical staff. Proper cleaning of surgical instruments is critical and should follow the guidelines set by The American Society of Cataract and Refractive Surgery TASS Task Force. When TASS occurs, sharing information with other ophthalmologists and reporting new causes is crucial for the prevention of outbreaks.

Conclusions

Anterior segment surgeons should be reminded that TASS is mostly preventable by the establishment of TASS prevention protocols, regular surgical staff training and thorough adherence to recommendations for cleaning and sterilizing intraocular surgical instruments.

Intracameral Use of Nepafenac: Safety and Efficacy Study

PURPOSE

To test the intracameral safety of nepafenac and its efficacy in inhibiting prostaglandin synthesis during phacoemulsification surgery.

METHODS

The safety evaluation was conducted in normal eyes of rabbits, 0.1ml of 0.3% and 1% nepafenac was injected intracamerally. Extensive studies to detect adverse response ranged from a gross examination of eyes under slit lamp biomicroscope, fluorescein dye test, Schirmer tear test, test for corneal sensitivity, intraocular pressure measurement (IOP), specular microscopy, electroretinography(ERG), and histopathological examination of intraocular tissues. Efficacy of nepafenac was studied by intracameral injection of 0.1%, 0.3% nepafenac, nepafenac 0.3%+1% lignocaine, and 1% lignocaine alone, before phacoemulsification surgery and intraoperative mydriasis along with PGE2(ProstaglandinE2) secretion were recorded.

RESULTS

Single 0.1ml of 0.3% or 1% nepafenac did not significantly (p > 0.05) alter physiological parameters and histology of cornea, iris, and retina. Nepafenac 0.3% effectively inhibited PGE2 secretion. No significant (p > 0.05) prevention of miosis was recorded with 0.1% or 0.3% nepafenac. However, a combination of 0.3% nepafenac + 1% lignocaine and 1% lignocaine alone significantly (p < 0.05) arrested miosis during the intraoperative period.

CONCLUSION

An intracameral concentration of up to 1% nepafenac does not adversely affect the rabbit eye. Nepafenac fails to prevent miosis but inhibits prostaglandin release during phacoemulsification surgery.