Management of Intraoperative Miosis during Pediatric Cataract Surgery using Healon 5

Cataract surgery in children using intracameral mydriatic

PURPOSE

To study the pupil dynamics with premixed intracameral anesthetic mydriatic combination of phenylephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) in pediatric cataract surgery.

METHODS

Consecutive children aged ≤12 years planned for cataract surgery were recruited. A commercially available premixed combination of phenylephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) was injected at the beginning of surgery without any topical/infusion drugs for mydriasis. Pupil sizes at various points of surgery were studied.

RESULTS

We recruited 75 patients with a mean age of 24.3 ± 33.4 months (range: 1 month-11 years). Adequate mydriasis with a single injection was achieved in 93.5% (n = 73 eyes of 70 patients) without additional pharmacotherapy or intervention. The mean pupillary diameter increased from 1.8 ± 0.79 to 6.1 ± 1.4 mm after injection (mean change of 4.2 ± 1.25 mm from baseline). The mean variability in pupillary diameter was 0.73 ± 1.3 mm. In five eyes, good dilatation was not possible even after repeat injection.

CONCLUSION

Fixed-dose premixed intracameral injection is effective in pupil dilatation. It alleviates the need for any topical dilators or additional intraoperative supplementation for pediatric cataract surgery.

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.

Dilation devices in cataract surgery

PURPOSE OF REVIEW

Cataract surgery in the setting of small pupil represent a major challenge and it is associated with a higher risk of complications. When pharmacologic pupil dilation fails, mechanical pupil expansion devices are needed to obtain and maintain sufficient intraoperative mydriasis. The purpose of this review is to assess the pupil expansion devices currently available.

RECENT FINDINGS

A variety of pupil expansion devices are offered on the market. They differ for design, material, shape, size, cost, and easiness of insertion/removal, nonetheless they all seem to be effective in improving the pupil size and easing the cataract surgery.

SUMMARY

Mechanical pupil expansion can be effectively achieved with a variety of devices, which are well tolerated and can facilitate cataract surgery in the setting of poor mydriasis.

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.

Intraoperative Evaluation of Phacoemulsification Cataract Surgery with and without the Use of Ophthalmic Viscosurgical Devices

PURPOSE:

The purpose of this study was to compare the efficacy and safety of cataract surgery by the phacoemulsification technique with and without the use of ophthalmic viscosurgical devices (OVDs).

SETTING:

This study was conducted at a tertiary eye care center in a rural area of Central India.

DESIGN:

This was a prospective, randomized, observational study.

METHODS:

In this study, 220 patients underwent phacoemulsification for cataract surgery with OVDs (OVD group) or without OVDs (BSS group) (n = 110 in each group). Patients with operable, nuclear Grade 2–4 cataracts were included in the study. The study was conducted from June 2017 to September 2018. The frequency of intraoperative complications, surgical time, and ease of the surgical procedure (easy, difficult, or very difficult) were recorded.

RESULTS:

There was no statistically significant difference in the nuclear opalescence, axial length, and intraocular lens (IOL) power between the two groups. Capsulorhexis extension was seen in two eyes in the OVD group and none of the eyes in the BSS group. The problems that occurred during IOL implantation included flip (OVD group, 2; BSS group, 1), haptic breakage (OVD group, 1; BSS group, 1), sulcus implantation (OVD group, 0; BSS group, 2), and stuck haptic (OVD group, 1; BSS group, 3). The total surgical time was almost equal in the two groups (OVD group, 9.2 min ± 3; BSS group, 9.5 min ± 3.5; P = 0.521). None of the patients had iris trauma or posterior capsular rupture.

CONCLUSIONS:

OVD-less phacoemulsification surgery is a safe and effective technique for treating age-related cataracts that requires no additional instrumentation and saves the cost of the OVD.

Techniques of anterior capsulotomy in cataract surgery

Optimal outcomes of a cataract surgery largely depend on the successful performance of an anterior capsulotomy. It is one of the most important steps of modern cataract surgery which reduces the risk of capsular tears and ensures postoperative stable intraocular lens (IOL). Anterior capsulotomy is considered ideal if it is round, continuous, well-centered, and overlaps the implanted IOL around its circumference. If any of these features is missing, it can be a cause of impedance for desired surgical and visual outcomes. Manual can opener and manual capsulorhexis are the routine standard techniques employed for manual extracapsular cataract extraction and phacoemulsification, respectively. Recent increasing use of femtosecond laser cataract surgery has allowed cataract surgeons to obviate inherent inaccuracies of manual anterior capsulotomy techniques. There is an ongoing quest to find an ideal, risk free, and surgeon-friendly technique of anterior capsulotomy that can be employed for surgery in all types of cataracts.

Cataract surgery in small pupils

This paper presents the review of historical aspects and the current state-of-the-art in various pupil dilatation methods to be used in cataract surgery. The surgical algorithm in managing small pupil cases should include topical and intraocular mydriatics, appropriately selected viscosurgical device and mechanical dilatation with instruments, iris hooks, and/or pupil expanders.

Recent advances in small pupil cataract surgery

PURPOSE OF REVIEW

To highlight the existing and emerging cataract surgery trends in patients with insufficient mydriasis. Discuss the latest pharmacological approaches for pre and intraoperative pupil dilatation. Present the variety of newest pupil expansion devices; critically review their advantages and possible limitations to be considered by the surgeon.

RECENT FINDINGS

The intracameral use of various mydriatic combinations augmenting the preoperative mydriatic instillations is currently gaining popularity in cataract surgery. Two main options are available: bolus injection of pharmacological agent or its constant irrigation during the phacoemulsification procedure. The former is aimed to expand the pupil, whereas the latter is mostly preventing the pupil from constriction. Introduction of femtosecond-assisted cataract surgery, apart from some benefits was followed by a variety of adverse effects including prostaglandin release into the aqueous humor causing pupil constriction. Preoperative administration of nonsteroidal anti-inflammatory drugs at least 1 day prior to surgery significantly decreases the chance of pupil constriction after laser energy is applied to the eye. However, pupil expansion devices may be needed in up to 10% of cases. Following the success of the Malyugin ring (MicroSurgical Technology Inc., Redmond, Washington, USA) several manufacturers introduced pupil expansion devices of various designs. They are differing with materials, pupillary margin fixation mechanisms, and easiness of manipulations during implantation and removal.

SUMMARY

Combination of proper use of pre and intraoperative pharmacological pupil dilatation protocols combined with pupil expander rings allow for well tolerated and effective cataract surgery in the vast majority of patients with insufficient mydriasis.

Small pupil and cataract surgery

PURPOSE OF REVIEW

Presence of a small pupil is still considered a major challenge for cataract surgeons. Appropriate mydriasis and maintaining it is of paramount importance to prevent potential serious complications. Recently, more interventions and instruments are available for the cataract surgeons to deal with these challenging cases. The intention of this review is to discuss the preoperative and intraoperative considerations and techniques for cataract surgery in small pupil and related conditions and to discuss new developments in management of small pupil in femtosecond laser-assisted cataract surgery.

RECENT FINDINGS

There are new techniques and pharmaceuticals available to cataract surgeons in the setting of small pupil. Intracameral ketorolac may soon be available to maintain mydriasis and to control pain and inflammation. Malyugin ring has been added to pupil expansion rings and has already been used for small pupil in different settings. In femtosecond laser-assisted cataract surgery, presence of a small pupil can now be managed by applying intracameral mydriatics and intraocular devices successfully.

SUMMARY

Accurate preoperative examinations adjunct with intraoperative use of appropriate pharmacologic and mechanical devices can yield favorable outcomes in cataract surgery with a small pupil.

Capsulorhexis: Pearls and pitfalls

A critical step in phacoemulsification (as well as extracapsular cataract extraction) is making a window in anterior capsule wall (i.e. anterior capsulotomy). Continuous Curvilinear Capsulorhexis (CCC) has become recognized as the standard method of anterior capsulectomy. Techniques employed for CCC have undergone sustained evolution. The present review evaluates elementary principles of CCC. Management of CCC in the presence of small pupil and pseudoexfoliation syndrome is discussed. Main differences of pediatric CCC from its adult-style counterpart and finally several techniques of rescue of an extending capsulorhexis are also reviewed.