Active clinical trials for "Cataract"

Pterygium is known to induce with-the-rule astigmatism. The corneal curvature along the long axis of the pterygium body is flattened. The excision of pterygium will result in steepening of the cornea and reduction of astigmatism. Therefore, the effect of pterygium excision on intraocular lens (IOL) power calculation has been examined in our previous study. The study confirmed that pterygium can cause alteration of IOL power. The determination of IOL power for cataract surgery is usually calculated from IOL formula called SRK II formula. IOL power = A - (2.5 x AL)-(0.9 x K). Variable A denotes the A-constant of the intraocular lens which is dependent on the IOL material and refractive index. Other variables for input include axial length (AL) and keratometry (K). A larger K reading will result in a lower estimated IOL power and vice versa. Previous studies have documented simultaneous cataract and pterygium operation resulted in reasonable visual outcome without adjustment of IOL power. With the presence of a pterygium, the cornea is flattened and lead to a reduction of K value and over-estimation of calculated IOL power. This randomized controlled trial is designed to compare the refractive outcomes of sequential and simultaneous pterygium and cataract operation. Pterygium excision should be done with various adjuvant therapies to minimize recurrence. Our previous studies reliably demonstrated limbal conjunctival graft and mitomycin C were effective methods to achieve low pterygium recurrence. We use limbal conjunctival autograft as the adjuvant therapy in the current study because this method is safer to be performed either alone or in combination with phacoemulsification. We avoid using mitomycin C as the adjuvant therapy in order to minimize the possibility of intraocular toxicity due to seepage.

The LensAR Laser System is used to create an opening in the anterior capsule of the lens and fragments the cataractous lens. The study will evaluate clinical outcomes compared to the contra-lateral eye treated with conventional phacoemulsification surgery.

To study the efficacy of an ocular bandage contact lens for the treatment of dry eye after complicated and combined cataract surgery

Previously, the investigators have developed a surgical technique to reduce inflammatory response after congenital cataract surgery. This prospective, randomized controlled study aims to compare the prognosis of traditional cataract surgery with traditional surgery combined triamcinolone staining of the anterior vitreous in treating congenital cataracts.

To compare the safety and efficacy of a new multi-functional cataract-assisted surgical instrument with that of traditional cataract-assisted surgical instrument in cataract surgery with subluxation of lens.

CleaRing is intended to reduce posterior capsular opacification in cataract patients. The device is intended to be implanted together with standard posterior chamber IOL during cataract surgery.

It is a comparative study of Safety and Efficacy of Three Variants of Canaloplasty: ab-externo, ab-interno and minicanaloplasty. Combined With Phacoemulsification to Treat Glaucoma and Cataract. It is a Randomised, Prospective Study.

This study evaluates the association between surgery of the cataract and posterior vitreous detachment, in the emmetropic patient, by comparing eyes operated with eyes not operated in the same group of patients

Cataract surgery is one of the most frequently performed surgeries worldwide and complications are rare. However, there are factors that increase the risk of complications, such as poor pupil dilation and intra-operative floppy iris syndrome (IFIS). Reasons for a small pupil size are pseudoexfoliation syndrome (PXF) syndrome, uveitis or synechia and the use of pilocarpin drops. IFIS is a syndrome usually caused by systemic alpha1-blockers (foremost tamsulosin) used to treat benign prostatic hyperplasia.1,2 As described by Chang and Campbell3 IFIS is characterized by billowing of a flaccid iris stroma, a propensity for iris prolapse towards the phacoemulsification tip as well as towards the incisions and progressive intra-operative pupil constriction. Stopping tamsulosin pre-operatively did not show to effectively prevent IFIS.4,5 However, it is of high importance to identify patients prior to surgery, who are treated with alpha1-blockers, or patients with a small pupil size and poor pharmacological pupil dilation. Some methods, such as intracameral injection of phenylephrine is only sufficient in a few cases 6, and a disadvantage is the risk of a hypertensive episode.7 Another pharmacological method is the use of atropine drops pre-operatively, but this method did not show to sufficiently reduce IFIS.4 Different methods were shown to reduce intra-operative problems due to IFIS/small pupil size: The use of highly cohesive ophthalmic viscosurgical devices (OVD), also called viscoadaptives, such as sodium hyaluronate (e.g. AMO Healon5 or Croma Eyefill H.D.) help to viscodilate the pupil and by resting on the iris during the entire phacoemulsification procedure reduce the risk of iris prolapsing towards the incisions. This method is more dependent on a central phacoemulsification technique and low fluidic parameters to allow the OVD to stay on the iris during the entire procedure.8 In case of a small pupil, pupil stretching with 2 instruments can be used additively. Another option to stabilize the pupil size is the use of mechanical pupil expansion devices, such as Iris retractors - these devices are routinely used to dilate the pupil intra-operatively. Typically, 4 or 5 iris retractors, also called iris hooks, are inserted through 4-5 incisions. Usually, the IFIS pupil is very elastic and the risk of overstretching is small.8 Pupil expansion rings, such as the Malyugin ring. This ring is placed on the pupil margin with an injector through the main incision. It eliminates the need of additional incisions and saves time.9 Rationale To compare different methods to manage IFIS and poor pupil dilation in cataract surgery: a pupil expansion ring (Malyugin Ring), iris retractors (iris hooks) and a viscoadaptive OVD.

The primary purpose of the protocol is to evaluate whether Trientine Hydrochloride, a copper chelator which is an agent that binds with and removes copper, will be effective in minimizing macular edema after cataract surgery in individuals with type 2 diabetes. It is our hypothesis that there will be a reduction in copper-attributed inflammation after surgery resulting a decrease in edema.