Effect of tropicamide on aqueous flare before and after cataract surgery

The Value of Laser Flare Photometry as a Monitoring Tool for Uveitis

Laser flare (LF) photometry (P) is used to quantify the protein concentration in the aqueous humor, and therefore assess the blood-aqueous humor barrier. LFP is more reliable than the clinical assessment of the Tyndall effect, and is thus especially useful in the follow-up of uveitis patients. In active uveitis, LFP correlates well with the anterior chamber cell grading. Various studies have shown that high LF values are associated with an increased risk of uveitic complications, such as macular edema, glaucoma, and posterior synechiae. LFP can also be used to assess the response to anti-inflammatory treatments as well as the optimal timing and selection of the surgical technique for intraocular surgeries.

Relationship Between Prolonged Intraocular Inflammation and Macular Edema After Cataract Surgery

Purpose

To assess whether aqueous flare is related to an increased risk of pseudophakic cystoid macular edema (PCME) following uneventful cataract surgery in nondiabetic and diabetic patients.

Methods

A post hoc analysis of five consecutive randomized clinical trials in the Department of Ophthalmology, Kymenlaakso Central Hospital, Finland. Aqueous flare levels were recorded in 448 eyes of 448 patients before surgery, and after the course of topical anti-inflammatory treatment 28 days and three months after cataract surgery.

Results

Aqueous flare increase of <50%, ≥50%, ≥100%, and ≥200% associated in central subfield macular thickness (CSMT) increase across the groups at 28 days and three months after surgery. Increase of aqueous flare ≥100% compared to those with <100% was associated with increased CSMT (P = 0.022 at 28 days, and P = 0.027 at three months). At three months, macular thickening (at least 10% CSMT increase) was observed in 12.7% compared to 4.6% of eyes when using a cutoff value of 100% increase in aqueous flare (P = 0.033). Although diabetic patients presented higher aqueous flare levels at baseline compared to nondiabetic patients (12.9 ± 11.8 vs. 9.8 ± 8.2 photon units/ms P < 0.001), the postoperative levels illustrated a similar profile in aqueous flare increase between the two groups.

Conclusions

At 28 days, aqueous flare increase was associated with macular thickening. A 100% cutoff value could potentially be used when studying anti-inflammatory efficacy of different treatment protocols. Flare values exceeding this cutoff value could be considered as an indication for extending anti-inflammatory therapy.

Translational Relevance

A 100% increase in aqueous flare at 28 days after cataract surgery from baseline predicted macular thickening up to three months postoperatively. Identifying a correlation between increased aqueous flare levels and pseudophakic cystoid macular edema may allow recognition of the most vulnerable patients, development of prophylactic treatment strategies and reduction of the number and severity of postoperative complications.

Bioinorganic chemistry of open-angle glaucoma: A review

At present, physical methods of chemical analysis are constantly improving providing large amount of data on elemental composition of organs and tissues. However, only few works describe the correlation (or the potential connection) between the general or local bioelemental imbalances and specific biochemical reactions that are involved in pathogenesis of certain diseases. This review describes primary open-angle glaucoma (POAG) - one of the most common ophthalmic diseases - in terms of elemental chemistry. The authors look into the impact that various subgroups of elements have on passive and active processes of homeostasis regulation and hydrodynamic balance in the eye. Alkaline metals and their analogues (K, Na, Li, Rb, Cs) influence hydrostatics and hydrodynamics by means of both K-Na pumps and osmosis. Alkaline-earth elements and their analogues (Ca, Mg, Sr, Ba, Be) are involved in biomineralization and intercellular interaction in the drainage areas. Chalcophile metals and their analogues (Zn, Cu, Hg, Co, Ni, Cd, Pb, Mo, Sb) regulate redox reactions. They are the cofactors of enzymes that support structural homeostasis of the drainage area. Siderophile metals (Fe, Mn, Cr, Rh) regulate oxidation-reduction reactions, including those associated with limited nutrition of tissues in glaucoma. The role of amphoteric metals and nonmetals (Al, Si, Ga, V, TI, Sn, Ge, Zr, W) in POAG has not been described properly, but they were noted to participate in mineralization. Structure-forming non-metals and their analogues (N, S, Se, As) are directly involved in the formation of protein and non-protein aggregates that prevent aqueous humor outflow. The specific role of phosphorus in the pathogenesis of glaucoma has not been described previously. The authors analyze the involvement of phosphorus in energy-dependent processes of cellular activity, which are aimed at the reprocessing of aggregates that cause aqueous humor retention.

The effects of tropicamide and cyclopentolate hydrochloride on laser flare meter measurements in uveitis patients: a comparative study

PURPOSE

To investigate the effects of 1% cyclopentolate hydrochloride and 1% tropicamide eye drops on aqueous flare measurements by using the laser flare meter.

METHODS

One hundred forty eight eyes of 83 patients with inactive uveitis were enrolled. The patients were randomly assigned to receive either 1% tropicamide (Group 1) or 1% cyclopentolate hydrochloride (Group 2) as the mydriatic agent. Best corrected visual acuity (BCVA), intraocular pressure (IOP), aqueous flare reaction levels measured by laser flare meter device (FM 600, Kowa, Kowa Company Ltd, Nagoya, Japan) before and post dilatation agents were evaluated.

RESULTS

Group 1 consisted of 75 eyes and Group 2 consisted of 77 eyes. The mean age of Group 1 patients was 34.85 ± 12.60 (range, 12-64) years; the mean age of Group 2 was 36.92 ± 13.30 (range, 12-70) years (p > 0.05). The mean BCVAs of two groups were 0.16 ± 0.43 (range, 0.00-3.10) logMAR and 0.17 ± 0.42 (range, 0.00-3.10) logMAR, respectively. There were no statistically significant differences between Groups 1 and 2 regarding gender or clinical characteristics (p > 0.05). No significant differences were detected in pre- or post-dilatation values between two groups (p = 0.470, p = 0.998).

CONCLUSIONS

As a result, anterior chamber flare values in uveitis patients do not differ significantly between 1% tropicamide and 1% cyclopentolate hydrochloride, and both agents can be safely used for dilatation during examination of patients with uveitis.

A Case of Bilateral Delayed-onset Hyphema Following Pupil Dilation after Gonioscopy-assisted Transluminal Trabeculotomy

Aim and objective

To present a case of bilateral delayed-onset hyphema following the administration of a 1% tropicamide and 2.5% phenylephrine fixed combination ophthalmic agent, in the late follow-up period of a gonioscopy-assisted transluminal trabeculotomy (GATT) combined with cataract extraction.

Background

Gonioscopy-assisted transluminal trabeculotomy consists on a 360° trabeculotomy through an ab interno approach that may also be combined with cataract surgery. Delayed-onset hyphema has been reported with trabecular minimally invasive glaucoma surgery (MIGS) procedures. Some proposed mechanisms are ocular compression and decompression during sleeping on the surgical side and episcleral venous pressure rise after physical activity.

Case description

We describe the case of a 68-year-old female patient with ocular hypertension (OHT) and bilateral cataracts who underwent uncomplicated combined GATT and cataract extraction surgery. Postoperatively, 8 months after the left eye (OS) surgery and 3 months after the right eye (OD) surgery, patient came for routine evaluation. After induced mydriasis, slit-lamp evaluation revealed the presence of 3+ OD and 4+ OS erythrocytes in the anterior chamber (AC). Prednisolone acetate was prescribed q.i.d. and remission of hyphema was achieved after 2 weeks. Subsequently, 4 months later, the pupil dilation was again induced showing 4+ erythrocytes in both eyes (OU), layered hyphema in the inferior quadrant OS, and intraocular pressure (IOP) spike OU. The intraocular pressure was controlled after oral acetazolamide was prescribed. Topic prednisolone was initiated, and after 1 week, the hyphema was resolved in OU.

Conclusion

Delayed-onset microhyphema may occur following induced mydriasis even months after the uncomplicated GATT procedure. Ophthalmologists should be aware of the possibility of microhyphema after induced mydriasis and the risks that this might represent with noteworthy and repeated IOP spikes which may eventually require treatment.

Clinical significance

Delayed-onset hyphema and IOP spikes may occur following the pupil dilation with fixed combination of phenylephrine and tropicamide ophthalmic agent after the uncomplicated GATT procedure.

How to cite this article

Espinoza G, Rodriguez-Una I, Pedraza-Concha A. A Case of Bilateral Delayed-onset Hyphema Following Pupil Dilation after Gonioscopy-assisted Transluminal Trabeculotomy. J Curr Glaucoma Pract 2020;14(2):72-75.

Incidence of pseudophakic cystoid macular edema in eyes with and without pupil expansion device

PURPOSE

Novel pupil expansion devices are widely recognized for their intraoperative feasibility in safe small pupil cataract surgeries. To assess whether the use of pupil expansion devices affects recovery from cataract surgery.

METHODS

A post hoc analysis of five consecutive prospective randomized clinical trials. 536 eyes of 536 patients undergoing routine cataract surgery were analysed according to the use of pupil expansion device. Thirty-four eyes were operated with pupil expansion device and 502 eyes without. Clinical outcome parameters were recorded at 28 days and 3 months.

RESULTS

Patient age and gender distribution, and baseline clinical outcome parameters were comparable between study groups. Pseudoexfoliation syndrome, glaucoma and medication for benign prostatic hyperplasia were more frequently present; phacoemulsification energy was higher and operation time longer in eyes with pupil expansion device. At 28 days, aqueous flare increased by 12.0 ± 25.1 pu/mseconds and mean central subfield macular thickness by 16.2 ± 24.4 μm in eyes with pupil expansion device, when compared to 4.6 ± 14.8 pu/mseconds (p = 0.015) and 7.0 ± 33.9 μm (p = 0.064) in eyes without the device. At 3-month follow-up, clinically significant pseudophakic cystoid macular edema (PCME) was reported in 12% of eyes with pupil expansion device and in 2% of eyes without (p = 0.006). After adjusting for the presence of confounding factors, hazard for clinically significant PCME was greater in eyes with pupil expansion device than in those without (HR 5.41, 95% CI 1.35-21.71, p = 0.017).

CONCLUSIONS

The use of pupil expansion device may predispose eyes to increased risk of clinically significant PCME. Effective anti-inflammatory treatment and follow-up are warranted in eyes with pupil expansion device.

Effect of Tropicamide on Laser Flare Meter Measurements in Patients with Pseudoexfoliation

PURPOSE

To investigate the effect of 1% tropicamide on anterior chamber aqueous flare (ACAF) measurements acquired with laser flare meter in patients with pseudoexfoliation.

METHODS

Thirty-three eyes of 33 patients with pseudoexfoliation were enrolled. Patients with the history of other ocular diseases, intraocular surgeries, and the presence of severe posterior synechia were excluded. Besides routine ophthalmological examination, ACAF levels were measured by laser flare meter device (Kowa FM 600) before and after instillation of 1% tropicamide.

RESULTS

The mean age of 33 patients was 67.3±7.1 (53-85) years. Patients had a mean best corrected visual acuity of 0.25±0.41 (1.80-0.00) logMAR, cup-to-disc ratio of 0.45±0.22 (0.2-1), and IOP of 15.33±2.82 (9-20) mmHg. Although the mean ACAF value increased from 14.68±8.40 (3.4-40.4) photon/ms predilation to 15.41±10.74 (3.8-46.8) photon/ms post-dilation, the difference was not statistically significant (p=0.835).

CONCLUSIONS

ACAF values in patients with pseudoexfoliation did not significantly differ after instillation of 1% tropicamide.

Ocular Spot Fluorometer Equipped With a Lock-In Amplifier for Measurement of Aqueous Flare

Purpose

To evaluate a custom-made ocular fluorometer for detection of intensity of light scatter (ILS) from the anterior chamber (A/C) as an objective measure of aqueous flare.

Methods

The fluorometer, equipped with a lock-in amplifier, was employed in the scatter mode to detect ILS from A/C. Measurements were performed with two illumination slit widths of 0.5 and 0.25 mm. The axial resolution at these slit widths were 80 and 200 μm, respectively. Healthy and pseudophakic eyes, with grade 0 Standardization of Uveitis Nomenclature (SUN) score, were employed as control subjects. ILS was also recorded in a cohort of patients who had undergone phacoemulsification and showed grades 1+ or 2+ on postoperative days 1 and 4.

Results

The inter- and intraobserver variabilities in the measurement of ILS were not significant. In cataract patients, ILS was significantly higher on postoperative day 1 relative to healthy eyes. By day 4, ILS decreased significantly and was only marginally different from ILS in quiet pseudophakic eyes or healthy eyes. Eyes with higher SUN scores showed proportionately increased ILS. The receiver-operator characteristic analysis indicated no advantage in using the smaller slit width in discriminating ILS at different SUN scores although it provided higher axial resolution.

Conclusions

The lock-in–based spot fluorometer is reliable for measurement of ILS with high precision and accuracy.The measured ILS correlates linearly with SUN scores and can be used to provide a higher granularity for recording aqueous flare.

Translational Relevance

The instrument can be used in the clinical management of uveitis and drug development toward uveitis.

Preoperative aqueous humour flare values do not predict proliferative vitreoretinopathy in patients with rhegmatogenous retinal detachment

BACKGROUND/AIMS

Patients with rhegmatogenous retinal detachment (RRD) who develop postoperative proliferative vitreoretinopathy (PVR) have been found to have higher preoperative laser flare values than patients with RRD who do not develop this complication. Measurement of laser flare has therefore been proposed as an objective, rapid and non-invasive method for identifying high-risk patients. The purpose of our study was to validate the use of preoperative flare values as a predictor of PVR risk in two additional patient cohorts, and to confirm the sensitivity and specificity of this method for identifying high-risk patients.

METHODS

We combined data from two independent prospective studies: centre 1 (120 patients) and centre 2 (194 patients). Preoperative aqueous humour flare was measured with a Kowa FM-500 Laser Flare Meter. PVR was defined as redetachment due to the formation of traction membranes that required reoperation within 6 months of initial surgery. Logistic regression and receiver operating characteristic analysis determined whether higher preoperative flare values were associated with an increased risk of postoperative PVR.

RESULTS

PVR redetachment developed in 21/314 patients (6.7%). Median flare values differed significantly between centres, therefore analyses were done separately. Logistic regression showed a small but statistically significant increase in odds with increasing flare only for centre 2 (OR 1.014; p=0.005). Areas under the receiver operating characteristic showed low sensitivity and specificity: centre 1, 0.634 (95% CI 0.440 to 0.829) and centre 2, 0.731 (95% CI 0.598 to 0.865).

CONCLUSIONS

Preoperative laser flare measurements are inaccurate in discriminating between those patients with RRD at high and low risk of developing PVR.

Laser flare-cell photometer: principle and significance in clinical and basic ophthalmology

A slit-lamp examination is an indispensable and essential clinical evaluation method in ophthalmology, but, it is qualitative subjective. To complement its weaknesses in making a quantitative evaluation of flare intensity and number of cells in the aqueous humor in the eye, we invented the laser flare-cell photometer in 1988. The instrument enables a non-invasive quantitative evaluation of flare intensity and number of cells in the aqueous with good accuracy and repeatability as well as maneuverability equal to slit-lamp microscopy. The instrument can elucidate the pathophysiology in the blood-aqueous barrier (BAB) function in a variety of ocular disorders. The accuracy of the instrument makes it possible to investigate not only the pathophysiology of intraocular disorders but also the effects of various drugs and surgical procedures in BAB. The instrument does not only lighten the burden on patients in clinical examinations and study but it also helps minimize the sacrifice of experimental animals and improves the reliability of the results by minimizing inter-individual variations through its good repeatability. Here I shall relate how the instrument has been applied to clinical and basic studies in ophthalmology and what novel knowledge its application contributed to pathophysiology in ophthalmology.

Effect of heparin coating of a foldable intraocular lens on inflammation and capsular bag performance after cataract surgery

PURPOSE

To evaluate the effect of a heparin-coated foldable intraocular lens (IOL) on postoperative flare in high-risk patients.

SETTING

Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN

Randomized clinical trial.

METHODS

This study included patients with diabetes mellitus (DM), pseudoexfoliation syndrome (PXF), or both scheduled for cataract surgery in both eyes. One eye received a coated IOL (Polylens EC-1YH PAL) and the other eye, an uncoated control IOL (Polylens EC-1Y PAL). Aqueous flare measurements were taken using a laser flare meter (FM-600, Kowa) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively. Visual acuity and anterior (ACO) and posterior (PCO) capsule opacification were assessed, and IOL centration and tilt were measured with a Purkinje meter.

RESULTS

Eighty eyes of 40 patients were included in the study; 64 eyes of 32 patients completed the study. The mean flare values (photons/ms) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively were 6.98 ± 3.71 (SD), 19.14 ± 18.90, 16.62 ± 25.33, 10.33 ± 9.70, 8.74 ± 4.64, respectively, with the coated IOL and 8.65 ± 5.73, 22.08 ± 16.23, 13.44 ± 13.71, 7.50 ± 4.11, and 7.03 ± 3.70, respectively, with the control IOL. No significant differences were found in flare, visual acuity, ACO, PCO, tilt, or centration between the coated IOL and the control IOL at any timepoint.

CONCLUSION

No significant differences in flare or capsule performance were found between the coated IOL and control IOL.

Efficacy and tolerability of preservative-free and preserved diclofenac and preserved ketorolac eyedrops after cataract surgery

PURPOSE

To compare the anti-inflammatory efficacy and subjective tolerability of preservative-free and preserved diclofenac 0.1% and preserved ketorolac 0.5% eye drops for prophylaxis and management of inflammation after cataract surgery.

DESIGN

Prospective, randomized, investigator-masked, parallel-group, comparative clinical trial.

METHODS

One hundred two patients who underwent small-incision phacoemulsification cataract surgery in an institutional setting were assigned randomly to receive preservative-free diclofenac sodium 0.1% (Voltaren ophtha SDU; Novartis Pharma), preserved diclofenac sodium 0.1% (Voltaren ophtha; Novartis Pharma), or preserved ketorolac tromethamine 0.5% (Acular; Pharm Allergan) eyedrops 4 times daily for 4 weeks after surgery. During the 1-month follow-up, anterior chamber flare and mean foveal thickness were evaluated for objective comparison of the anti-inflammatory effect. Ocular tolerability was assessed by observer-based grading of conjunctival hyperemia and ocular discomfort, as well as obtaining subjective ratings of ocular tolerability on a visual analog scale. Distance and near visual acuity and intraocular pressure served as safety measures.

RESULTS

All 3 formulations demonstrated equal anti-inflammatory efficacy as measured by reduction of anterior chamber flare after surgery and prevention of postoperative macular edema. Patients treated with preservative-free diclofenac eyedrops reported significantly better subjective tolerability values (P = .001), were classified as having less ocular discomfort (P < .001), and experienced earlier reduction of postoperative conjunctival hyperemia (P = .029).

CONCLUSIONS

Anti-inflammatory efficacy was comparable for all 3 agents. However, preservative-free diclofenac 0.1% eyedrops exhibited a significantly better postoperative subjective and objective tolerability when compared with preserved eyedrops containing ketorolac or diclofenac.

Laser flare-cell photometry: methodology and clinical applications

Diagnosis and management of intraocular inflammation involves the assessment of cells and protein levels ("flare") in the aqueous humor. These factors are difficult to quantify precisely on clinical examination alone. Laser flare-cell photometry provides an automated technique to quantify these factors objectively, and it has been used in a variety of research and clinical situations to assess anterior segment inflammation. Any new technique requires evaluation to determine accuracy and reproducibility of measured values, and initial applications require critical appraisal to assess the value of the technique. Both in vitro and in vivo studies of laser flare-cell photometry have been performed to determine its validity and utility as a research and clinical tool. This article reviews published studies that describe the technique of laser flare-cell photometry; it provides new in vitro data that supplements information on the capabilities of this technique and factors that influence photometry results, and it reviews representative publications that have used laser flare-cell photometry for study of specific disease entities. This information can help clinicians and researchers to become familiar with the strengths and limitations of laser flare-cell photometry, to identify appropriate future uses for this technique, and to use it and interpret its results appropriately. Laser flare-cell photometry offers an opportunity to improve upon current techniques of inflammation assessment and should not be considered simply an objective surrogate for clinical grading of cells and flare at the slit-lamp biomicroscope. Its research applications and utility for monitoring patients with uveitis have not yet been fully explored.

Early objective assessment of intraocular inflammation after phacoemulsification cataract surgery

PURPOSE

To evaluate the time course of blood-aqueous barrier (BAB) disturbance in the early period after small-incision cataract surgery.

SETTING

Department of Ophthalmology, Vienna University, Vienna, Austria.

METHODS

In a prospective study, 15 eyes of 15 patients with age-related cataract had small-incision cataract surgery by phacoemulsification with intraocular lens implantation. Care was taken to minimize trauma to the uvea during surgery. Postoperative inflammation was assessed by measuring aqueous flare and cell count with a laser flare-cell meter. Postoperative measurements were performed hourly for the first 6 hours, every 2 hours until 12 hours, every 4 hours until 40 hours, and every 8 hours until 56 hours.

RESULTS

The time course of aqueous flare and cell count differed significantly among patients. The peak inflammatory response in most cases was 1 hour after surgery, with the response decreasing thereafter. The pattern of the time course was classified into subgroups defined by the presence and size of an initial spike immediately after surgery and the intensity of the subsequent inflammatory reaction. A slight increase in flare and cells was seen in the morning hours of the first postoperative day.

CONCLUSIONS

Acute BAB disturbance within the first 48 hours after small-incision cataract surgery showed high interpatient variability. However, many differences were not detectable 1 day after surgery.

Postoperative inflammation after lens epithelial cell removal: 2 year results

PURPOSE

To evaluate the influence on postoperative inflammation of lens epithelial cell (LEC) removal after phacoemulsification.

SETTING

Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS

This randomized prospective single-surgeon study comprised 60 patients with senile cataract only. After a temporal clear corneal incision was made and phacoemulsification performed, no LECs were removed in Group A, LECs in the nasal half were removed in Group B, and LECs were removed from the entire anterior capsule in Group C. The LECs were removed with a Rentsch capsule curette (Geuder). In all eyes, a foldable hydrogel intraocular lens (Hydroview, Bausch & Lomb) was implanted. Anterior chamber flare was evaluated through dilated pupils in a double-masked fashion using a Kowa FC-1000 laser flare-cell meter (LFCM). Measurements were done preoperatively as well as 1, 3, 7, 14, and 28 days and 3, 6, 12, and 24 months postoperatively.

RESULTS

In all 3 groups, the flare and cell values increased on the first postoperative day followed by a successive decrease thereafter. One month after surgery, the blood-aqueous barrier (BAB) was nearly restored in all groups. Between the first and fourth week, the flare values in Groups B and C were slightly lower than in Group A; however, mean flare and cell values among groups were not statistically significantly different at any measurement.

CONCLUSION

The removal of LECs from the anterior capsule with a Rentsch curette did not influence postoperative BAB changes detected using an LFCM.