A bisulfite-free intraocular epinephrine solution

Toxic anterior segment syndrome (TASS): A review and update

Toxic anterior segment syndrome (TASS) is an acute, sterile, postoperative inflammatory reaction of the anterior segment without vitreous involvement, following an uncomplicated and uneventful ocular surgery, having broad and multiple etiologies. The symptoms of decreased visual acuity and ocular discomfort generally occur within the first 12-48 h after intraocular surgery. The clinical signs include prominent limbus-to-limbus corneal edema, anterior chamber cells, aqueous flare, fibrinous inflammation, and/or keratic precipitates. There can be sight-threatening complications of TASS, such as permanent corneal decompensation, intractable glaucoma, and cystoid macular edema. The causes of TASS are emerging and being reported, so are the newer treatment options for managing the inflammation and its complications. Prevention guidelines for TASS are being updated, and a traceability system for surgical instruments and intraocular fluids used during the surgery is being perpetually developed. It is important to recognize TASS and start treatment on an immediate effect. Hereby, we review the literature on TASS, emphasizing its etiology, pathophysiology, management, prognosis, complications, and the importance of prevention as well as prompt recognition.

Phacoemulsification without preoperative topical mydriatics: induction and sustainability of mydriasis with intracameral mydriatic solution

Context:

Intracameral mydriatic solution can eliminate the disadvantages of repeated eye drop instillation regimen and provide adequate mydriasis for phacoemulsification with added advantages.

Aims:

Evaluating the role of intracameral irrigating solution (0.5% lignocaine + 0.001% epinephrine) in initiating and maintaining the pupillary mydriasis during phacoemulsification. Secondary aims were to observe the effect of surgical time, nucleus density and ultrasound time on mydriasis during the procedure.

Settings and Design:

The study is a prospective interventional case series, conducted at tertiary care institution.

Materials and Methods:

Thirty patients underwent phacoemulsification under topical anesthesia for visually significant cataract. Pupillary dilatation was achieved by intracameral irrigation of mydriatic solution alone. Pupillary diameter was measured serially during surgery and ultrasound time and total surgical time were noted.

Statistical Analysis Used:

Paired samples student–t test was done to compare means. Spearman correlation coefficient was used to study the effect of various parameters on mydriasis.

Results:

Thirty eyes completed the study. The pupil size increased from 2.1 mm (Range 2-3.5 mm SD ± 0.32) to 6.9 mm (Range 5-9 mm SD ± 1.02) in 30 seconds time after intracameral mydriatic solution delivery, and was 7.0 mm (Range 3.5 - 9 mm SD ± 0.20) at the end of surgery. Duration of surgery, grade of nucleus and ultrasound time had statistically insignificant effect on mydriasis.

Conclusions:

Intracameral solution containing 0.5% lignocaine and 0.001% epinephrine provides rapid mydriasis which is adequate for safe phacoemulsification and is unaffected by other parameters.

Effect of preoperative use of topical prednisolone acetate, ketorolac tromethamine, nepafenac and placebo, on the maintenance of intraoperative mydriasis during cataract surgery: a randomized trial

Purpose:

To compare the effects of preoperative use of topical anti-inflammatory prednisolone acetate, ketorolac tromethamine, nepafenac and placebo, on the maintenance of intraoperative mydriasis during cataract surgery.

Design:

Randomized clinical trial.

Materials and Methods:

This single-center, masked, randomized clinical study comprised 140 patients scheduled for cataract surgery. Patients (35 in each group) were randomized to receive placebo, prednisolone acetate, ketorolac tromethamine 0.4% or nepafenac. These eye drops were administered three times daily for the two days prior to surgery. The pupillary diameters were measured by the surgeon using a compass prior to the corneal section and at the end of surgery. The primary outcome was the number of patients with pupil ≥ 6mm at the end of the surgery; the secondary outcome was the number of patients with pupil ≥ 6mm at the beginning of the surgery.

Results:

All the patients achieved pupil ≥ 6mm at the beginning of the surgery. The number of patients in the prednisolone (29/35), nepafenac (31/35) and ketorolac (30/35) groups with pupil ≥ 6mm was greater than in the placebo group in the maintenance of intraoperative mydriasis (19/35 – P =0.003). There was no statistical difference among the prednisolone, nepafenac and ketorolac groups in the maintenance of intraoperative mydriasis (P =.791). There were no complications during surgery or related to the preoperative use of the eye drops.

Conclusion:

Preoperative use of ketorolac, prednisolone and nepafenac was effective in maintaining intraoperative mydriasis when compared with placebo.

Intraoperative floppy iris syndrome (IFIS): a practical approach to medical and surgical considerations in cataract extractions

Intraoperative floppy iris syndrome (IFIS) during cataract surgery is characterized by iris fluttering, iris prolapse towards the incisions, and a progressive pupillary constriction leading to high rates of complications. The syndrome has been reported following the treatment of benign prostatic hyperplasia with α-1(a) adrenergic receptor inhibitors, especially tamsulosin. The present paper describes the syndrome and discusses its pharmacological background. Several techniques to prevent and to deal with the syndrome are presented.

Intracameral mydriatics in phacoemulsification surgery obviate the need for epinephrine irrigation

PURPOSE

To evaluate the possibility of removing epinephrine from the irrigating solution in phacoemulsification surgery when using intracameral mydriatics (ICMs).

METHODS

We carried out a prospective, randomized, double-blinded study of 140 patients with age-related cataracts, scheduled for unilateral phacoemulsification. The first part of the study involved 90 patients divided into two groups. Patients in both groups were given 150 microl ICMs at the beginning of the procedure. In group 1, 0.6 microg/ml epinephrine was added to the irrigating balanced salt solution. No epinephrine was added to the irrigation solution used in group 2. The second part of the study involved 50 patients, all of whom were given topical mydriatics (TMs) and then similarly divided into two groups and treated as in the first study setting.

RESULTS

With ICMs, pupil sizes generally increased during the procedures. Remarkably, this increase was significantly greater without epinephrine (13 +/- 19% versus 4 +/- 14%; p = 0.02). In the TMs setting, pupil sizes decreased intraoperatively in both groups; significantly more without epinephrine (- 5 +/- 4% versus - 12 +/- 7%; p < 0.001).

CONCLUSIONS

An irrigating solution without epinephrine can safely be used with ICMs. The increase in pupil size during the procedure is greater without epinephrine. This study also confirms earlier findings that epinephrine is beneficial when using TMs.

Cytotoxicity of Lidocaine or Bupivacaine on Corneal Endothelial Cells in a Rabbit Model

PURPOSE

To investigate the corneal endothelial cytotoxicity of commercial formulations of agents used for intracameral anesthesia in cataract and other ocular surgery.

METHODS

Cultured corneal endothelial cells (CECs) of New Zealand White rabbits were exposed for 1 minute to balanced salt solution (control); Xylocaine (lidocaine) 1% E (with epinephrine), 2% E, 2%, or 4%; or Marcaine (bupivacaine) 0.5% or 0.5% spinal heavy. The degree of cytotoxicity was determined by in vitro staining with trypan blue and light microscopic evaluation of cell morphology. The effect of longer exposure (up to 16 minutes) to lidocaine 1% E was also investigated.

RESULTS

CECs were not significantly damaged by 1-minute exposure to lidocaine 1% E or 2% E; however, significant cytotoxicity was seen after 1-minute exposure to lidocaine 2% or 4% or bupivacaine 0.5% or 0.5% spinal heavy. Exposure to lidocaine 1% E showed a trend toward time-dependent cytotoxicity that reached significance at 16 minutes.

CONCLUSIONS

One-minute exposure to lidocaine 1% E or 2% E appears to be safe for cultured rabbit CECs, although longer exposures could cause time-dependent cytotoxicity, which should be considered in planning cataract or other ocular surgery. Because bupivacaine 0.5% and 0.5% spinal heavy cause cytotoxic effects within the first minute of contact with CECs, they should be used with great caution, if at all, in the anterior chamber of human eyes.