Pupil dilation dynamics with an intracameral fixed combination of mydriatics and anesthetic during cataract surgery

A Modular Cataract Surgery Training Model Incorporating Human Factors and a Pedagogical Theory

Synopsis

High volume cataract lists are cost-effective, reduce waiting times, and facilitate surgical teaching. We propose a stepwise training model that incorporates human factor principles and a reflective pedagogical approach, which has not been documented previously.

Background/Aims

Surgical training in ophthalmology is effective when a modular approach is utilised. High volume lists further enhance training by increasing exposure to a newer way of learning and working. We evaluated the efficiency and safety of trainee-assisted cataract surgery across a single NHS eye unit and an independent sector (IS) provider.

Methods

We examined results from audits of surgical efficiency and safety in trainee-assisted high-volume lists, including a single-centre comparative evaluation of consultant-only and trainee lists. The quantitative and qualitative information gained from these projects helped us to implement a modular, structured training programme that utilises a reflective cycle of pedagogy, suitable for any grade of trainee.

Results

Our projects included an audit following cataract surgery performed by a surgical trainee over a 5-month period, which showed excellent post-op refractive results and no cases of intra-operative and post-operative complications. A single-centre observational study demonstrated comparable surgical throughput and safety results for trainee and solo consultant high volume lists. Systemic and ocular complication rates were reported to be similar for low and medium risk cataract surgery among trainee supervised IS and NHS lists.

Conclusion

Cataract surgery outcomes and patient feedback support the effectiveness of the surgical training model. Combining Gibbs' reflective cycle of critical reflection with the International Council of Ophthalmology's principles helped us to develop the QM Model of modular teaching for cataract surgery, which we believe is suitable for utilisation in all surgical centres in the NHS and IS settings, for both low volume and high-volume surgical lists regardless of trainee experience.

Safety of an Intracameral Fixed Combination for Mydriasis and Intraocular Anaesthesia During Cataract Surgery

Purpose

To compare the safety of a standardized, commercially available intracameral combination of mydriatics and anesthetic (ICMA) with a reference topical mydriatic regimen for cataract surgery.

Patients and Methods

The safety results from two international, randomized, controlled clinical studies were combined to compare ICMA at the beginning of cataract surgery (ICMA group) to the reference topical mydriatic regimen (reference group). Data were collected on ocular and systemic adverse events, corneal and anterior chamber examination, endothelial cell density, retinal thickness and visual acuity. Analysis was performed on a pooled safety set from both studies, preoperatively and up to 1 month postoperatively.

Results

342 patients received ICMA and 318 the reference topical regimen. Ocular adverse events were reported in 17.0% of patients in the ICMA group and 18.6% in the reference group. No difference was shown between groups in endothelial cell density (2208 ± 498 cells/mm2 for ICMA group versus 2241 ± 513 cells/mm2 for the reference group; p=0.547) and retinal thickness (change from baseline less than 50 µm in 94.7% versus 95.0% of patients, respectively) at 1 month postoperatively. At 1-day post-surgery, less patients in the ICMA group had moderate or severe (Grades 2 and 3) superficial punctate corneal staining (3.9% versus 7.0% for the reference group; p=0.064). Postoperatively, some ocular symptoms were also less frequently reported in the ICMA group. Best-corrected visual acuity increased in 96.0% of patients in the ICMA group and 95.8% in the reference group at 1 month.

Conclusion

ICMA injection at the beginning of cataract surgery was demonstrated to be safe and may also provide perioperative and postoperative advantages over the standard topical mydriatic regimen.

Intracameral phenylephrine for surgical mydriasis and intraoperative floppy-iris syndrome: systemic adverse effects and optimal dose

Phenylephrine, a potent sympathomimetic, induces mydriasis via iris dilator muscle contraction. Intracameral (IC) phenylephrine has been successfully used in cataract surgery for initial mydriasis, maintaining mydriasis, and management of intraoperative floppy-iris syndrome. Serious systemic adverse events (mainly cardiovascular) have been described with topical phenylephrine drops, but we found very little evidence of such adverse events associated with IC phenylephrine use. However, we suspect under-reporting of such adverse events, as they may instead be ascribed to anxiety, positioning, anesthesia, etc. Optimal dosage/concentrations for IC phenylephrine use in different purposes have not been fully studied. In the absence of robust evidence, we suggest that lower but effective IC phenylephrine concentrations are used: a lower concentration (0.31%), in conjunction with an anticholinergic and lidocaine, may be used for initial mydriasis. For management of intraoperative floppy-iris syndrome, 0.31% may be effective, though a higher concentration (1% to 1.25%) may be required.

Effectiveness of a Standardized Combination of Intracameral Mydriatics and Anaesthetic on Mydriasis during Cataract Surgery with Coexisting Diseases

PURPOSE

To examine the effectiveness of a standardized combination of intracameral mydriatics and anesthetic (SCIMA) on mydriasis in patients with coexisting diseases such as diabetes mellitus (DM) and pseudoexfoliation syndrome (PXF) during phacoemulsification.

METHODS

Patients with cataract were included in the study if they achieved pupil dilation diameter ≥ 6.0 mm after the administration of mydriatic eyedrops (ME) during the first visit (V1). During the second visit (V2), pupil size measurements were obtained for phacoemulsification surgery with SCIMA. Effective mydriasis was defined as a pupil diameter ≥ 6.0 mm just prior to capsulorhexis without the use of additional pupil dilating agents. The measurements after ME administration during V1 and after SCIMA use during V2 were compared.

RESULTS

103 patients (103 eyes) were divided into 3 groups: cataract and DM (n = 35), cataract and PXF (n = 32), and cataract without DM or PXF (n = 36). SCIMA administration allowed the achievement of effective mydriasis (≥6.0 mm) in all groups (n = 103; 100%). Mydriasis was significantly larger (p ≤ 0.001) after ME (7.3 mm) than after SCIMA (6.8 mm) administration.

CONCLUSIONS

Patients with cataract and such comorbidities as DM or PXF are likely to achieve effective pharmacological mydriasis during cataract phacoemulsification after SCIMA application. Mydriasis after ME is slower and larger, while SCIMA is faster.

Pharmacological management of intra-operative miosis during cataract surgery

Cataract surgery requires a well-dilated and stable pupil for a good outcome. Unexpected pupillary constriction during surgery increases the risk of complication. This problem is more pronounced in children. There are now pharmacological interventions that help tackle this unforeseen happening. Our review discusses the simple and quick options available to a cataract surgeon when faced with this dilemma. As cataract surgical techniques continue to improvise and get faster, an adequate pupil size is of paramount importance. Various topical and intra-cameral drugs are used in combination to achieve mydriasis. Despite good pre-operative dilation, the pupil can be quite unpredictable during surgery. Intra-operative miosis limits the field of surgery and increases the risk of complications. For example, if the pupil size decreases from 7 mm to 6 mm, this 1 mm change in pupil diameter will lead to a decrease of 10.2 mm2 in the area of surgical field. Making a good capsulorhexis with a small pupil can be a challenge, even for an experienced surgeon. Repeated touching of the iris increases the risk of fibrinous complications. Removal of cataract and the cortical matter becomes increasingly difficult. Intra-ocular lens implantation in the bag also requires adequate dilation. When dealing with challenging cases like lens subluxation, pseudo-exfoliation, and zonular dehiscence, a small pupil further increases the risk and adversely affects the surgical outcome. Hence, achieving and maintaining adequate mydriasis throughout surgery is essential. This review highlights the risk factors for small pupils during surgery and current management strategies.

Pupil diameter during cataract surgery after intracameral injection of the first ready-to-use combination of mydriatics and anaesthetic at the beginning of surgery in patients with a preoperative pupil diameter <6 mm

PURPOSE

We evaluated, in a real-life setting, the effect of Mydrane® (ready-to-use combination of tropicamide, phenylephrine hydrochloride and lidocaine, injected into the anterior chamber at the beginning of cataract surgery to induce mydriasis and intraocular anaesthesia) on the pupil diameter during cataract surgery in patients with a preoperative pupil diameter <6 mm after the use of topical mydriatics.

METHODS

We collected and analysed the data of 59 consecutive patients whose pupils dilated to a diameter <6 mm after the administration of mydriatic eye drops during the preoperative visit and who received Mydrane® during cataract surgery.

RESULTS

In the group of 59 patients with a preoperative pupil diameter <6 mm after topical mydriatics, cataract surgery was performed in 36 patients (61.0%) using only Mydrane® to obtain mydriasis, with no additional drug or medical device. The mean pupil diameters in this group (36 of 59) during the preoperative assessment after topical mydriatics and just before capsulorhexis when Mydrane® was injected during surgery were 5.1 ± 0.74 and 6.15 ± 1.14 mm. Additional drugs were used in 23 patients (39%). In this group, the mean pupil diameters after topical mydriatics and just before capsulorhexis using Mydrane® were 4.58 ± 1.06 and 5.6 ± 1.26 mm, respectively.

CONCLUSION

In a real-life setting, the mean pupil diameter achieved during cataract surgery after the intracameral injection of Mydrane® in patients with a preoperative pupil diameter <6 mm was over 1 mm larger than the mean pupil diameter after topical mydriatics, despite the trauma caused by the operation.

Perioperative time and economic impact of an intracameral combination of mydriatics and anaesthetics in routine cataract surgery

PURPOSE

The aim of this study was to compare the perioperative time and economic impact of a licensed intracameral anaesthetic/mydriatic combination (Mydrane) during routine cataract surgery.

METHODS

A real-life, prospective, comparative study was performed in 3 clinical centres in France. Preoperative, surgical, and post-operative times were determined for two mydriasis strategies using conventional preoperative mydriatics/anaesthetics eye drops (control regimen) or Mydrane administered at time of surgery. Staff, surgery schedules and drugs utilisation were collected over 12 surgery half-days. The total cost of each strategy was estimated based on treatment cost and nursing costs.

RESULTS

The analysis included 112 routine cataract surgeries (57 surgeries using Mydrane and 55 using the topical regimen) without protocol deviations or complicated surgery. Overall, the mean time between administration of the first mydriatic eye drops or Mydrane and the end of the surgery was 27.4 ± 21.1 min in the Mydrane group vs. 90.3 ± 30.4 min in the control group (P < 0.0001). The total time of the procedure (from admission to discharge) was not significantly different between groups (P = 0.1611). On average, the extra cost of drugs per patient in the Mydrane group (€5.81) was almost balanced by the reduced nursing time (€5.57) with some variations between centres, due to different organisation including staff resource and consumable.

CONCLUSIONS

The Mydrane strategy produced perioperative nursing time saving and cost reduction provided that adaptation and reorganisation of routine cataract surgery are implemented.

Efficacy of the intracamerally administered mydriatics for cataract surgery in patients with primary open-angle glaucoma

PURPOSE

To compare Mydrane®, mydriatic eye drops, and Mydriasert® in terms of pupil site stability, surgical time, visual field, and anterior chamber configuration modifications among patients with primary open-angle glaucoma (POAG) during cataract extraction surgery.

METHODS

Retrospective analysis of sixty patients with POAG and cataract who underwent elective cataract extraction. All patients underwent routine ophthalmic examinations, including automatic visual field examination, anterior chamber configuration, specular microscopy, and arterial blood pressure measurement prior to surgery, and 24 h and 30 days postoperatively. All cataract surgeries were video-recorded and all measurements were performed using a media player. Patients divided into groups 1, 2, and 3 (n = 20 in each group) received topical mydriatic eye drops, Mydriasert®, and an intracameral injection of Mydrane®, respectively, immediately after the first incision.

RESULTS

The mean change in pupil size from just before capsulorhexis to the end of surgery was 0.43 ± 0.09, 0.42 ± 0.08, and 0.36 ± 0.02 mm in groups 1, 2, and 3, respectively. The mean surgery duration was similar among all the groups. The baseline main cell density slightly decreased at 24 h and remained stable for 30 days postoperatively. The mean deviation and pattern standard deviation remained stable at 1 month after surgery. At 24 h after surgery, the nasal irido-corneal angle, temporal-iridocorneal angle, and anterior chamber depth increased compared with the baseline, remaining stable for 30 days after surgery.

CONCLUSIONS

Mydrane® produced adequate and stable mydriasis as effectively as produced by Mydriasert® and topical eye drops.

Efficacy of a hinged pupil expansion device in small pupil cataract surgery

Purpose:

To evaluate the efficacy and safety of a hinged pupil expansion device (PED) in eyes with small pupils undergoing phacoemulsification.

Methods:

In this prospective, multicenter, interventional case series of 57 eyes with suboptimal pharmacologic pupil dilation (<5 mm diameter), a hinged PED (I-Ring, Beaver-Visitec International, Waltham, MA) was applied to facilitate surgical visualization during cataract surgery. The pupil diameters (PD) were measured at different stages of the procedure and at the 1-month follow-up visit. Rate of successful intraoperative PED deployment, pupil size, and shape were assessed.

Results:

The mean patient age was 70.5 ± 12.1 years. The I-Ring PED was successfully applied in all eyes. The mean PD at various stages were 4.1 ± 1.1 mm (dilation with eye drops only preoperatively), 4.3 ± 1.1 mm (dilation after intracameral epinephrine and ophthalmic viscoelastic device), 6.80 ± 0.00 mm (with PED applied), and 5.7 ± 1.1 mm (end of surgery). A statistically significant difference (P < 0.001) was observed between the mean PD with intracameral medications and with PED application. Postoperative circular pupil was observed in 54 of 57 eyes (94.7%) and the mean eccentricity index (n = 57 eyes) was 0.11 ± 0.22. No significant adverse events were observed.

Conclusion:

The I-Ring PED safely and effectively provided and maintained adequate pupil expansion and surgical visualization in eyes with small pupils undergoing cataract surgery. Postoperatively 95% of eyes attained circular pupils. This hinged PED is an additional instrumentation option for the safe and effective expansion of inadequately sized pupils during cataract surgery.

Cost analysis of mydriasis strategies in cataract surgery care in the Netherlands

PURPOSE

To investigate the economic impact of an intracameral mydriatics and anesthetic agent (ICMA), topical mydriatics, and a mydriatic ocular insert in cataract patients.

SETTING

One public hospital in the Netherlands.

DESIGN

Prospective cohort study.

METHODS

Resource use data were collected from a healthcare and societal perspective on the day of surgery. Other outcome parameters included pupil size, surgeon satisfaction, postoperative pain, and Catquest-9SF scores.

RESULTS

A total of 368 patients were included, the mean costs per patient were €506 in the ICMA group (n = 122), €474 in the ocular insert group (n = 115), and €451 in the topical group (n = 131). The acquisition cost of ICMA was highest and resulted in longer surgical time. After correction for an imbalance in the distribution of fast and slow surgeons, the mean costs in the ocular insert and topical groups were comparable (€450 vs €444). There was no statistically significant difference in the use of additional mydriatics intraoperatively (P = .521). The mean ratio of pupil size to white-to-white distance was lower in the ICMA group during all intraoperative measurements (P < .001) but similar between the topical and ocular insert groups (P range .11-.82).

CONCLUSIONS

In the investigated setting in the Netherlands, ICMA was the most costly strategy. In addition, pupil size was lowest in the ICMA group but did not result in more additional mydriasis measures intraoperatively. The ocular insert was comparable with topical mydriatics in costs and pupil size. Implementation of ICMA could be considered when availability of nurses or physical space for perioperative care is limited.

Intracameral anesthetic mydriatic (ICAM) assisted pediatric cataract surgery

PURPOSE

To assess the efficacy and safety of intracameral mydriatic and anesthetic combination for pupillary dilation in pediatric cataract surgery.

METHODS

This prospective series included children <12 years, with visually significant unilateral or bilateral cataracts planned for cataract surgery with/without intraocular lens implantation. At the beginning of surgery, 0.025 ml of a combination of phenylephrine hydrochloride (0.31%), tropicamide (0.02%), and lidocaine hydrochloride (1%) was injected intracamerally. The efficacy of the combination was tested by achieving capsulorhexis and intraocular lens implantation without additional mydriatics.

RESULTS

We recruited 13 patients (16 eyes) with a mean age of 4.1 ± 3.9 years. The mean pupillary diameter changed increased from 1.92 to 5.68 mm after injection of one unit (0.025 ml) of drug (p < 0.0001). There was a strong positive correlation of the pupillary dilation with axial length (R = 0.86) and horizontal corneal diameter (R = 0.81). Seventy-five percent patients had a pupillary diameter >6 mm and surgery could be completed successfully in all cases without additional mydriatics. In all cases, pupil dilated as the surgery progressed. No adverse event to the drug was noted.

CONCLUSIONS

Intracameral mydriatic-anesthetic combination is an effective and safe way to obtain stable mydriasis in pediatric cataract surgery.

Safety and efficacy of a standardized intracameral combination of mydriatics and anesthetic for cataract surgery in type-2 diabetic patients

Background

Cataract surgery in diabetics is more technically challenging due to a number of factors including poor intraoperative pupil dilation and a higher risk of vision threatening complications. This study evaluates the safety and efficacy of an intracameral combination of 2 mydriatics and 1 anesthetic (ICMA, Mydrane) for cataract surgery in patients with well-controlled type-2 diabetes.

Methods

Post-hoc subgroup analysis of a phase 3 randomized study, comparing ICMA to a conventional topical regimen. Data were collected from 68 centers in Europe and Algeria. Only well-controlled type-2 diabetics, free of pre-proliferative retinopathy, were included. The results for non-diabetics are also reported. The primary efficacy variable was successful capsulorhexis without additional mydriatic treatment. Postoperative safety included adverse events, endothelial cell density and vision.

Results

Among 591 randomized patients, 57 (9.6%) had controlled type 2 diabetes [24 (42.1%) in the ICMA Group and 33 (57.9%) in the Topical Group; intention-to-treat (ITT) set]. Among diabetics, capsulorhexis was successfully performed without additional mydriatics in 24 (96.0%; modified-ITT set) patients in the ICMA Group and 26 (89.7%) in the Topical Group. These proportions were similar in non-diabetics. No diabetic patient [1 (0.5%) non-diabetics] in the ICMA Group had a significant decrease in pupil size (≥3 mm) intraoperatively compared to 4 (16.0%; modified-ITT set) diabetics [16 (7.3%) non-diabetics] in the Topical group. Ocular AE among diabetics occurred in 2 (8.0%; Safety set) patients in the ICMA Group and 5 (16.7%) in the Topical Group. Endothelial cell density at 1 month postoperatively was similar between groups in diabetics (P = 0.627) and non-diabetics (P = 0.368).

Conclusions

ICMA is effective and can be safely used in patients with well-controlled diabetes, with potential advantages compared to a topical regimen including reduced systemic risk, better corneal integrity and reduced risk of ocular complications.

Trial registration

The trial was registered at (reference # NCT02101359) on April 2, 2014.

Tropicamide/Phenylephrine/Lidocaine Intracameral Injection: A Review in Cataract Surgery

Tropicamide 0.02%/phenylephrine 0.31%/lidocaine 1% injectable solution (Mydrane^®) is the first fixed-dose mydriatic/anaesthetic combination approved for intracameral use in adults undergoing cataract surgery. In a phase 3 trial in this setting, intracameral tropicamide/phenylephrine/lidocaine was at least as effective as a standard topical regimen of tropicamide plus phenylephrine in enabling successful capsulorhexis without the use of additional mydriatics. The intracameral preparation, which is administered via a single injection, provides rapid and sustained mydriasis through to the end of surgery, with recipients spending around half as long in preoperative/surgery rooms as standard topical regimen recipients in the phase 3 study. Moreover, significantly more of the intracameral than topical regimen recipients were free from pain or pressure in the eye/orbit before intraocular lens (IOL) implantation and had an IOL implanted without complications. Intracameral tropicamide/phenylephrine/lidocaine also displayed mydriatic efficacy in patients with diabetes in this trial. Overall, the preparation was generally well tolerated, with no serious adverse events leading to hospitalization or permanent vision loss. Thus, tropicamide/phenylephrine/lidocaine injectable solution is an emerging option for mydriasis/anaesthesia in adults undergoing cataract surgery.

Drop-free approaches for cataract surgery

PURPOSE OF REVIEW

Routine prophylaxis for adverse events following cataract surgery is evolving. Prior reliance on topical eyedrop instillation by patients is giving way to surgeon directed injections at the time of cataract surgery. The benefit of this new approach is assured delivery of drugs in standardized doses which should optimize the healing process and reduce the incidence of untoward events with higher confidence.

RECENT FINDINGS

Adoption rates of intracameral antibiotic injection amongst European and American cataract surgeons is increasing. Techniques to inject periocular corticosteroid for routine inflammation prophylaxis are also in development. In combination with intraoperative pharmacologic dilation, a drop-free modality can be achieved.

SUMMARY

Intraoperative injections offer the patient and surgeon assured drug delivery and hold promise to avoid the pitfalls of patient adherence, incorrect topical instillation, and topical drop-associated corneal issues.

[Same-eye comparison of pupillary dilation with an intraoperative standardized intracameral combination of mydriatics (Mydrane®) versus a preoperative ophthalmic (Mydriasert®) in standard cataract surgery in non-diabetic patients (French translation of the article)]

INTRODUCTION

Cataract surgery is the most commonly performed surgery in the world, and its success depends in part on the quality of mydriasis.

PURPOSE

To compare, for the same eye, the pupillary dilation obtained with Mydrane® (standardized intracameral solution of 0.02% tropicamide, combined with 0.31% phenylephrine and 1% lidocaine) intraoperatively versus Mydriasert® (0.28mg tropicamide insert and 5.4mg phenylephrine) with a contact time between 45 and 60 minutes in the preoperative period.

METHODS

Single center prospective study from November 2016 to January 2018 at the Laveran Army Instructional Hospital in Marseille. Patients referred for surgery were dilated at the preoperative consultation with Mydriasert®. The pupillary diameter after 45-60 minutes of contact with the insert was manually measured, by two different examiners, through the "iris image" tab of the Pentacam® elevation topography. Patients were dilated on the day of their cataract surgery with 0.2cc of Mydrane® injected in the anterior chamber through a paracentesis. Thirty seconds later, prior to injection of viscoelastic, an eye photograph was taken by screen capture. The pupillary diameter was evaluated by two different examiners with to the Piximeter 5.9 metrology software. The difference in pupil dilation between Mydriasert® and Mydrane® was tested with the paired series Student t-test.

RESULTS

In total, 111 eyes of 82 patients were included. Mydriasert® achieved a mean pupillary dilation of 7.21±0.79mm. The mydriasis obtained with Mydrane® averaged 6.35±0.8mm. This difference of 0.86mm was statistically significant (P<0.001) with a confidence interval of 95% [-0.97; -0.74].

CONCLUSION

On average, Mydrane® dilates the pupil less than Mydriasert®. However, the mydriasis obtained with Mydrane® remains comfortable for the performance of the capsulorhexis. It helps save preoperative time and affords additional anesthetic to the cataract surgery. Nevertheless, the use of Mydriasert® is beneficial when extra mydriasis is required.

Systemic exposure to intracameral vs topical mydriatic agents: in cataract surgery

Objective

The objective of this study was to compare systemic exposure to tropicamide/phenylephrine following intracameral or topical administration before cataract surgery.

Patients and methods

Mydriatics exposure was calculated in patients randomized to intracameral fixed combination of mydriatics and anesthetic ([ICMA]: tropicamide 0.02%, phenylephrine 0.31%, and lidocaine 1%, N=271) or mydriatic eye drops ([EDs]: tropicamide 0.5% and phenylephrine 10%, N=283). Additional doses were permitted if required. Mydriatic plasma levels were determined by mass spectrometric HPLC in 15 patients per group before and after administration.

Results

Most ICMA patients (73.6%) received a single dose (200 µL) representing an exposure to tropicamide of 0.04 mg and phenylephrine of 0.62 mg. None of these patients received additional mydriatics. In the control group (three administrations), the exposure was 0.45 (11.3-fold higher than ICMA) and 10.2 (16.5-fold higher) mg. When additional ED was used in this group (9.2% of patients), it was 37.5-fold higher for tropicamide (10 drops, 1.5 mg) and 54.8-fold higher for phenylephrine (10 drops, 34 mg) than the recommended ICMA dose. Tropicamide plasma levels were not detectable at any time point in ICMA patients while it was detectable in all ED patients at 12 and 30 minutes. Phenylephrine was detectable in 14.3% of ICMA patients compared to all ED patients at least at one time point. More ED patients experienced a meaningful increase in blood pressure and/or heart rate (11.2% vs 6.0% of ICMA patients; P=0.03).

Conclusion

Systemic exposure to tropicamide/phenylephrine was lower and cardiovascular (CV) effects were less frequent with ICMA. This could be of particular significance in patients at CV risk.