Cases of toxic anterior segment syndrome after primary pterygium surgery

PURPOSE

Toxic anterior segment syndrome (TASS) is an acute, sterile, inflammatory reaction of the anterior segment after intraocular surgeries. We aimed to report an outbreak of TASS which occurred following pterygium surgeries.

METHODS

A case series.

RESULTS

Four eyes of four patients developed TASS associated with formaldehyde after uneventful primary pterygium surgery with conjunctival autograft. No patients reported pain; all patients demonstrated diffuse corneal edema, epithelial defects, and anterior chamber inflammation without hypopyon, fibrin formation, and vitreous involvement on the first postoperative day. TASS diagnosis was made based on clinical findings. All patients were treated with hourly topical 1% prednisolone acetate (Pred Forte, Allergan, CA), moxifloxacin 0.5% (Vigamox, Alcon, TX), and 0.24% of hyaluronic acid (Artelac complete, Bausch & Lomb). Oral steroid (prednisolone 1 mg/kg) was added on the first week and gradually tapered over weeks. None of the affected corneas improved spontaneously. Best-corrected visual acuity ranged from 20/25000 to 20/200 in the second month after surgery. Keratoplasty was scheduled for all patients.

CONCLUSIONS

This is the first study to present TASS cases after pterygium surgery. Clinicians should be aware of TASS that can emerge after an extraocular surgery. In our analysis, since 2% formaldehyde was used by the operating room personnel for cleaning and sterilizing reusable ocular instruments, it was thought that formaldehyde was the most likely cause.

Descemet Membrane Endothelial Keratoplasty in Toxic Anterior Segment Syndrome: A Case Series

PURPOSE

To evaluate the outcomes of Descemet membrane endothelial keratoplasty (DMEK) in patients with toxic anterior segment syndrome (TASS).

METHODS

Thirteen eyes of 13 patients who underwent DMEK for endothelial decompensation secondary to TASS were retrospectively reviewed. A comprehensive ocular examination including best-corrected visual acuity (BCVA), slitlamp biomicroscopy, intraocular pressure measurement, fundus evaluation, and measurement of central corneal thickness were performed in all patients at preoperatively and postoperatively.

RESULTS

There were 8 men and 5 women, with an average age of 56 ± 19 years. The mean follow-up was 8.7 ± 3.5 months. The time interval between the onset of TASS and DMEK was 4.9.±6.6 months (range, 1.5-26 months). Twelve of 13 grafts were clear at last visit. The mean preoperative BCVA was 20/666 (range, hand motion to 20/200), and the mean BCVA was 20/36 (range, hand motion to 20/20) at the postoperative last visit (P = 0.003). The decrease in mean pachymetry from preoperative (768 ± 69 μm) to postoperative last visit (523 ± 71 μm) was statistically significant (P < 0.001).

CONCLUSIONS

DMEK seems to be a safe and an effective treatment option in eyes with TASS-related endothelial decompensation.

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.

Interface fluid syndrome secondary to endothelial failure due to toxic anterior segment syndrome after cataract surgery

Purpose:

To present a case of previous laser in situ keratomileusis with interface fluid syndrome secondary to toxic anterior segment syndrome following cataract surgery.

Case report:

A 52-year-old woman, complaining blurred vision in her right eye for 18 months after cataract surgery, was referred to our clinic. She was diagnosed with toxic anterior segment syndrome, postoperatively, which resolved in 3 days. She had a history of laser in situ keratomileusis surgery 15 years ago. Slit-lamp examination of the right eye showed corneal haze, limited to laser in situ keratomileusis flap. The patient was diagnosed with interface fluid syndrome secondary to endothelial decompensation due to toxic anterior segment syndrome. Descemet’s membrane endothelial keratoplasy was performed along with full thickness fenestrations in the laser in situ keratomileusis flap to the right eye of the patient. The fluid was resolved in 1 week and visual acuity was improved rapidly.

Conclusion:

This case shows the importance of considering the diagnosis and determining the specific etiology of interface fluid syndrome, even years after the laser in situ keratomileusis surgery, when endothelial cell function has been compromised with any factor, such as intraocular surgery and its complications.

Corneal edema after phacoemulsification

Phacoemulsification is the most commonly performed cataract surgery in this era. With all the recent advances in investigations and management of cataract through phacoemulsification, most of the patients are able to achieve excellent visual outcome. Corneal edema after phacoemulsification in the immediate postoperative period often leads to patient dissatisfaction and worsening of outcome. Delayed onset corneal edema often warrants endothelial keratoplasty. This review highlights the etiopathogenesis, risk factors, and management of corneal edema in the acute phase including descemet's membrane detachment (DMD) and toxic anterior segment syndrome. Various investigative modalities such as pachymetry, specular microscopy, anterior segment optical coherence tomography, and confocal microscopy have been discussed briefly.

Toxic Anterior Segment Syndrome Outbreak after Cataract Surgery Triggered by Viscoelastic Substance

PURPOSE:

The purpose of this study is to present toxic anterior segment syndrome (TASS) outbreak at our clinic and discuss possible causes of TASS.

MATERIALS AND METHODS:

Thirty-four eyes of 34 patients developed TASS in a consecutive 2 weeks period were included in this study. Both anterior segment and fundus examinations were performed before and after uncomplicated cataract surgery. During the follow-up period, clinical features and all possible causes were evaluated including perioperative products and processing such as sterilization technique of surgical instruments, irrigating solutions, drugs, viscoelastic substance (VES), and intraocular lens.

RESULTS:

Patients had corneal edema, anterior chamber reactions, and decreased vision. No patient had purulent secretion, chemosis, lid involvement, and pain. At first 2 postoperative days, patients treated as infectious endophthalmitis by topical and oral antibiotics and then TASS was suspected, and patients treated completely with topical steroids. Suspected cause for TASS was VES substance, 2% sodium hyaluronate which had newly been used as VES product in phacoemulsification surgery. No new case has occurred after stopped usage of this VES product.

CONCLUSION:

As far as we know, this is the largest report of TASS outbreak in the shortest period from the same clinic caused by VES. Suboptimal products of surgical materials can be the cause of TASS. Close monitoring of each surgical step and elimination of causative agent can prevent the outbreaks of TASS.

Evaluation of the retinal, choroidal, and nerve fiber layer thickness changes in patients with toxic anterior segment syndrome

Purpose

To evaluate changes in choroidal, retinal, and nerve fiber layer (NFL) thickness following toxic anterior segment syndrome (TASS).

Methods

Macular and peripapillary choroidal thickness was measured using enhanced depth imaging (EDI) optical coherence tomography (OCT) on the day of the diagnosis and on three follow-up exams (months 1 to 4). A similar OCT analysis of central retinal and NFL thickness was performed.

Results

Thirteen TASS patients were included. Average age was 72.8 ± 8.7 years. Macular choroidal thickness in the superior, subfoveal, and nasal macula in the study eye was larger than the control eye and decreased at months 2–4. This was statistically significant only for the superior macula (p = 0.004). Peripapillary choroidal thickness was larger in the study eye at baseline compared with the control eye—significantly so in the nasal (p = 0.026) and inferior (p = 0.033) locations. Peripapillary choroidal thickness peaked at the baseline or 1st month exam and decreased thereafter. Retinal thickness increased significantly with time, peaking at the 2nd month and decreasing thereafter. No changes were found in the NFL.

Conclusions

TASS may have a transient effect on the choroid. Changes in retinal thickness are probably a normal transient postoperative response and not a result of TASS.