Intraocular lens scaffold | |
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Other names | Intraocular lens scaffold |
Specialty | ophthalmology |
Intraocular lens scaffold, [1] or IOL scaffold technique, is a surgical procedure in ophthalmology. In cases where the posterior lens capsule is ruptured and the cataract is present, an intraocular lens (IOL) can be inserted under the cataract. The IOL acts as a scaffold, and prevents the cataract pieces from falling to the back of the eye. The cataract can then be safely removed by emulsifying it with ultrasound and aspiration. This technique is called IOL scaffold, and was initiated by Amar Agarwal at Dr. Agarwal's Eye Hospital in Chennai, India.
The technique can be used to support and protect the posterior capsule membrane during a lens swap procedure. [1]
The lens capsule may be damaged due to trauma, from birth, or by surgery. [2] [3] During cataract surgery, when half or more of the lens remains and the surgeon notices capsule damage; the IOL scaffold technique can be used to capture the lens and prevent further complications. In this technique, the artificial lens or IOL is placed in the sulcus (remaining part of the lens bag) and phacoemulsification surgery using ultrasound is performed over it. Once the entire lens is removed, the IOL is well positioned on the sulcus. As soon as the surgeon notices the capsular tear or sinking nucleus, anterior chamber infusion can be used to stabilize the chamber. Anterior vitrectomy is performed to remove the vitreous body in the pupil and anterior part of eye. Then the IOL (already planned to be placed in the lens bag) is inserted under the nucleus on the remaining capsule bag. The nucleus is positioned on the IOL and the surgery is completed.[ citation needed ]
By this method, the risk of lens fragments falling into the vitreous body or back part of the eye is reduced. The IOL acts as a barrier or scaffold preventing the lens remnants from falling back. Since separation is present in the posterior (vitreous) eye from the anterior (aqueous) part, retinal risks are reduced. Moreover, neither special instruments nor additional training required once this method is learnt.[ citation needed ]
The intraocular lens scaffold technique was introduced by Dr. Amar Agarwal in 2012. He used this technique in a case which had posterior capsular rupture during a phacoemulsification procedure. [4]
The technique can be used for intraoperative nucleus removal during cataract surgery (phacoemulsification), removal of lens dropped on the retina, Sommering ring removal, intraocular foreign body removal, and IOL explantation. [4] [5] [6] [1] [7] [8]
In an eye with total loss of bag where no capsular bag remnant is present, glued IOL scaffold is used. [5] In this a glued IOL is placed behind the cataract pieces. The glued IOL then works as a scaffold and the cataract pieces are removed with the phaco handpiece using ultrasound. Two partial thickness scleral flaps measuring 2.5 to 2.5 mm are made 180 degrees diagonally apart. Infusion is placed by anterior chamber maintainer and sclerotomies are made below the flaps with 20 gauge needle. The IOL is injected below the remaining lens particles and the remaining lens is positioned on the artificial lens or IOL (Fig 2). The haptics of the IOL are brought out under the flaps as in the glued IOL method and tucked into the scleral tunnel made with 26 gauge needle at the entry site. The phacoemulsification procedure is then continued on the IOL and the anterior chamber is formed by the end of the procedure. Scleral flaps and conjunctiva are then closed with fibrin glue.
In the IOL scaffold, the IOL is placed above the iris or above some remnant of the capsule. Otherwise, a glued IOL then acts as a scaffold.[ citation needed ]
The Soemmering ring is the ring-shaped growth of lens cells after surgical removal of cataractous lens in childhood. This is seen as a peripheral ring after pupil dilatation. Patients who undergo artificial lens implantation in an eye that had earlier cataract surgery use this technique to remove the ring remnant. [6] Here the IOL is placed with the glued IOL scaffold method, the Sommering ring is dislodged on the IOL, and is removed (Fig 3).
Refractive surprise can happen after IOL implantation; incorrect lens or power is the probable cause for this. In that situation, the IOL is removed and an IOL of correct power is placed. IOL scaffold is used where the new IOL is placed into the lens bag below the old IOL. The new IOL acts as scaffold or barrier and helps as a platform for the removal of the old lens. [1]
External foreign bodies can enter the eye and become lodged on the retina or vitreous. This is often removed through the open method of opening through the sclera (white coat of the eye). While removing intraocular foreign bodies (IOFB), it may drop or slip onto the back of the eye (Fig 4). This will prevent the accidental slippage of IOFB into the eye.[ citation needed ]
No increased risk of postoperative complications such as endothelial decompensation or post-operative uveitis has been reported. [7] [8] Good visual outcomes are obtained. IOL has been reported to be stable without de-centering in both eyes.[ citation needed ]
A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision of the eye. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colours, blurry or double vision, halos around light, trouble with bright lights, and difficulty seeing at night. This may result in trouble driving, reading, or recognizing faces. Poor vision caused by cataracts may also result in an increased risk of falling and depression. Cataracts cause 51% of all cases of blindness and 33% of visual impairment worldwide.
Eye surgery, also known as ophthalmic surgery or ocular surgery, is surgery performed on the eye or its adnexa. Eye surgery is part of ophthalmology and is performed by an ophthalmologist or eye surgeon. The eye is a fragile organ, and requires due care before, during, and after a surgical procedure to minimize or prevent further damage. An eye surgeon is responsible for selecting the appropriate surgical procedure for the patient, and for taking the necessary safety precautions. Mentions of eye surgery can be found in several ancient texts dating back as early as 1800 BC, with cataract treatment starting in the fifth century BC. It continues to be a widely practiced class of surgery, with various techniques having been developed for treating eye problems.
Phacoemulsification is a cataract surgery method in which the internal lens of the eye which has developed a cataract is emulsified with the tip of an ultrasonic handpiece and aspirated from the eye. Aspirated fluids are replaced with irrigation of balanced salt solution to maintain the volume of the anterior chamber during the procedure. This procedure minimises the incision size and reduces the recovery time and risk of surgery induced astigmatism.
An Intraocular lens (IOL) is a lens implanted in the eye usually as part of a treatment for cataracts or for correcting other vision problems such as short sightedness and long sightedness, a form of refractive surgery. If the natural lens is left in the eye, the IOL is known as phakic, otherwise it is a pseudophakic lens. Both kinds of IOLs are designed to provide the same light-focusing function as the natural crystalline lens. This can be an alternative to LASIK, but LASIK is not an alternative to an IOL for treatment of cataracts.
A phakic intraocular lens (PIOL) is a special kind of intraocular lens that is implanted surgically into the eye to correct myopia (nearsightedness). It is called "phakic" because the eye's natural lens is left untouched. Intraocular lenses that are implanted into eyes after the eye's natural lens has been removed during cataract surgery are known as pseudophakic.
Cataract surgery, also called lens replacement surgery, is the removal of the natural lens of the eye that has developed a cataract, an opaque or cloudy area. The eye's natural lens is usually replaced with an artificial intraocular lens (IOL) implant.
Aphakia is the absence of the lens of the eye, due to surgical removal, such as in cataract surgery, a perforating wound or ulcer, or congenital anomaly. It causes a loss of ability to maintain focus (accommodation), high degree of farsightedness (hyperopia), and a deep anterior chamber. Complications include detachment of the vitreous or retina, and glaucoma.
Capsulorhexis or capsulorrhexis, and the commonly used technique known as continuous curvilinear capsulorhexis (CCC), is a surgical technique used to remove the central anterior part of the capsule of the lens from the eye during cataract surgery by shear and tensile forces. It generally refers to removal of the central part of the anterior lens capsule, but in situations like a developmental cataract a part of the posterior capsule is also removed by a similar technique.
Howard V. Gimbel FRCSC, AOE, FACS, CABES, is a Canadian ophthalmologist, university professor, senior editor, and amateur musician. He is better known for his invention, along with Thomas Neuhann, of the continuous curvilinear capsulorhexis (CCC), a technique employed in modern cataract surgery.
Eric John Arnott, MA, FRCS, FRCOphth was a British ophthalmologist and surgeon who specialized in cataracts, a condition which in many parts of the world still remains the principal cause of blindness. He is known for inventing new surgical techniques for treatment of various ophthalmological disorders, and received professional awards for his contributions.
Capsulotomy is a type of eye surgery in which an incision is made into the capsule of the crystalline lens of the eye. In modern cataract operations, the lens capsule is usually not removed. The most common forms of cataract surgery remove nearly all of the crystalline lens but do not remove the crystalline lens capsule. The crystalline lens capsule is retained and used to contain and position the intraocular lens implant (IOL).
The aim of an accurate intraocular lens power calculation is to provide an intraocular lens (IOL) that fits the specific needs and desires of the individual patient. The development of better instrumentation for measuring the eye's axial length (AL) and the use of more precise mathematical formulas to perform the appropriate calculations have significantly improved the accuracy with which the surgeon determines the IOL power.
David J. Apple was an ophthalmic pathologist who conducted research on the pathology of intraocular lens complications as well as ophthalmic surgery in general. He was a medical historian and biographer of Sir Harold Ridley, the inventor of the intraocular lens (IOL).
He often stated that Harold Ridley changed the world. What we can say about David Apple is that he vastly improved the world that Harold Ridley changed
Dr Amar Agarwal M.S., FRCS, F.R.C.Ophth is an Indian ophthalmologist and chairman and managing director of Dr. Agarwal's Eye Hospital and Eye Research Centre in India, which includes 140+ eye hospitals. He is the recipient of the Best Doctor award of the State government from then Chief Minister of Tamil Nadu J Jayalalithaa on 15 August 2014. He is also the past President of the International Society of Refractive Surgery (ISRS) and Secretary General of the Intraocular Implant and Refractive Society of India (IIRSI).
In ophthalmology, glued intraocular lens or glued IOL is a surgical technique for implantation, with the use of biological glue, of a posterior chamber IOL in eyes with deficient or absent posterior capsules. A quick-acting surgical fibrin sealant derived from human blood plasma, with both hemostatic and adhesive properties, is used.
Uveitis–glaucoma–hyphaema (UGH) syndrome, also known as Ellingson syndrome, is a complication of cataract surgery, caused by intraocular lens subluxation or dislocation. The chafing of mispositioned intraocular lens over iris, ciliary body or iridocorneal angle cause elevated intraocular pressure (IOP) anterior uveitis and hyphema. It is most commonly caused by anterior chamber IOLs and sulcus IOLs but, the condition can be seen with any type of IOL, including posterior chamber lenses and cosmetic iris implants.
Ophthalmic viscosurgical devices (OVDs) are a class of clear gel-like material used in eye surgery to maintain the volume and shape of the anterior chamber of the eye, and protect the intraocular tissues during the procedure. They were originally called viscoelastic substances, or just viscoelastics. Their consistency allows the surgical instruments to move through them, but when there is low shear stress they do not flow, and retain their shape, preventing collapse of the anterior chamber. OVDs are available in several formulations which may be combined or used individually as best suits the procedure, and are introduced into the anterior chamber at the start of the procedure, and removed at the end. Their tendency to remain coherent helps with removal, as the cohesive variants tend to be drawn into the aspiration orifice without breaking up.
Manual small incision cataract surgery (MSICS) is an evolution of extracapsular cataract extraction (ECCE); the lens is removed from the eye through a self-sealing scleral tunnel wound. A well-constructed scleral tunnel is held closed by internal pressure, is watertight, and does not require suturing. The wound is relatively smaller than that in ECCE but is still markedly larger than a phacoemulsification wound. Comparative trials of MSICS against phaco in dense cataracts have found no difference in outcomes but MSICS had shorter operating times and significantly lower costs. MSICS has become the method of choice in the developing world because it provides high-quality outcomes with less surgically induced astigmatism than ECCE, no suture-related problems, quick rehabilitation, and fewer post-operative visits. MSICS is easy and fast to learn for the surgeon, cost effective, simple, and applicable to almost all types of cataract.
Clear lens extraction (CLE), also known as refractive lensectomy or refractive lens exchange (RLE) is a surgical procedure in which clear lens of the human eye is removed. Unlike cataract surgery, where cloudy lens is removed to treat cataract, clear lens extraction is done to surgically correct refractive errors such as high myopia. It can also be done in hyperopic or presbyopic patients who wish to have a multifocal IOL implanted to avoid wearing glasses. It is also used as a treatment for diseases such as angle closure glaucoma.
Cataract surgery has a long history in Europe, Asia, and Africa. It is one of the most common and successful surgical procedures in worldwide use, thanks to improvements in techniques for cataract removal and developments in intraocular lens (IOL) replacement technology, in implantation techniques, and in IOL design, construction, and selection. Surgical techniques that have contributed to this success include microsurgery, viscoelastics, and phacoemulsification.