Nylon Verus Polyglactin Corneal Suture in Pediatric Cataract Surgery

Comparison Between Nylon and Polyglactin Corneal Suture in Pediatric Cataract Surgery: a Randomized Controlled Clinical Trial

Pediatric cataract surgery requires the suturing of the corneal incision in order to maintain the integrity of the eyeball and to help avoid the trauma often caused by scratching in the postoperative period of pediatric surgeries. Traditionally, this suturing is performed using 10-0 nylon material. Because this material is non-absorbable, it must be removed under sedation in cases of complications such as suture loosening, late suture lysis, accumulation of secretion on the suture, corneal neovascularization, and corneal ulceration. The objetive of this study is to compare the rate of postoperative complications and the need for suture removal after pediatric cataract surgery in cases in which nylon (non-absorbable) sutures are used versus cases in which polyglactin (absorbable) sutures are used.

This is a controlled, randomized, prospective, single-center study performed on patients undergoing pediatric cataract surgery at the Clinical Hospital of the University of Campinas (UNICAMP). The volunteers for whom cataract extraction surgery has been indicated and who have signed the ICF (or whose ICF has been signed by a parent or guardian) will undergo cataract surgery and the cornea will be sutured using a polyglactin 910 suture (Vicryl® 10-0). In the control group (Group B), the cornea will be sutured using nylon 10-0 sutures (the current routine procedure). All patients will be monitored for six months and will receive complete ophthalmological evaluations in order to determine whether they experience any suture-related complications and whether sutures must be removed under sedation. A lower incidence of complications and a less frequent need for suture removal under sedation are expected in the group receiving Vicryl® sutures.

Patients who are diagnosed with cataracts and for whom surgery is indicated shall be evaluated (as much as possible based on their ability to cooperate with the assessment) in terms of their visual acuity and refractive error via biomicroscopy, automated keratometry (Auto Kerato Refractometer KR 8000® Alcon), Goldmann applanation tonometry, fundoscopy, and biometric assessment (Ocuscan RxP® Alcon or Lenstar LS900® Haag-Streit International).

Patients who choose to sign (or whose guardians choose to sign) the informed consent form after being informed of all of the aspects of the surgery and this trial shall be randomly divided into one of two groups that shall be approximately equal in size and stratified by age.

• Up to 6 months of age
• From 6 to 12 months of age
• From 1 to 3 years of age
• From 3 to 6 years of age
• Older than 6 years Patients in Group A will have their surgical incisions sutured with polyglactin 10-0 material (Vicryl®, composed of polyglactin 910, 10-0 diameter, absorbable, a 0.62 cm, 3/8 circle needle) at the end of cataract surgery followed by the use of 0.5% moxifloxacin and 0.1% dexamethasone eye drops before the bandage is applied. Patients in Group B will have their surgical incisions sutured with nylon 10-0 material (Vicryl®, composed of nylon monofilament, 10-0 diameter, absorbable, a 0.55 cm, 1/2 circle needle) at the end of cataract surgery followed by the use of 0.5% moxifloxacin and 0.1% dexamethasone eye drops before the bandage is applied.

Cataract surgery will be performed using the standardized protocol in the Ophthalmology department of UNICAMP by fourth-year ophthalmology residents with experience in pediatric cataract surgery. Preoperative pupil dilation shall be performed through the use of 2.5% phenylephrine and 1% tropicamide 3 times in five-minute increments. General anesthesia shall be performed. Skin sterilization shall be performed using an aqueous solution of 10% povidone-iodine. After the sterile surgical field is established and the eyelashes are isolated, 4 eye drops containing 5% povidone-iodine shall be administered in the conjunctival sac with subsequent irrigation using a 10% balanced salt solution. In cases of allergy to povidone-iodine, an aqueous solution of 0.05% chlorhexidine shall be used. The main incision (either a clear corneal incision or a scleral tunnel) will be 2.2 mm to 3.0 mm, and aspiration will be applied using the Infiniti® or Laureate® phacoemulsifier (Alcon) with a foldable AcrySof® intraocular lens (Alcon) and a posterior capsulotomy with an automated vitrectomy only in cases in which it is indicated.

Neither patients nor surgeons will be masked to the study treatment. The postoperative consultations will be held on the first, seventh, thirtieth, ninetieth, one hundred and twentieth, and one hundred and eightieth postoperative days and will include visual acuity assessments, refractive error assessments, keratometry , biomicroscopy, applanation tonometry, and fundoscopy, depending on the patient's age and ability to cooperate. If a necessary exam is not possible in a clinical setting, it will be performed under sedation in the surgical center.

Primary outcome: frequency of complications associated with sutures in each group.

Secondary outcome: need for suture removal under sedation in each group. The following will be defined as suture-related complications: corneal neovascularization close to the suture, loosening of the suture, accumulation of mucus on the suture, early rupture (within 2 weeks or less) of the suture, aqueous humor leakage through the incision (as determined by the Seidel test), prolapse of the iris through the incision site, infectious or traumatic keratitis, endophthalmitis and giant papillary conjunctivitis as observed in a biomicroscopy exam using a slit lamp.

Based on the frequency of suture-related complications described in the literature and using a two-tailed 95% confidence interval, 80% power, an exposed/unexposed radius of 1, and a null frequency of complications in the polyglactin suture group, approximately 40 subjects are needed for each group. UNICAMP performs an average of 75 pediatric cataract surgeries per year. Thus, there is a perspective for patient inclusion and study completion of just over one year.

Inclusion Criteria:

• Patients up to 14 years of age who are clinically qualified to undergo pediatric cataract surgery

Exclusion Criteria:

• Traumatic cataract with ocular perforation
• Cataract surgery associated with other procedures, such as glaucoma filtering surgery, vitreoretinal surgery, and cornea surgery
• Signs of ocular or periocular infection
• Advanced glaucoma