Hubbry Logo
Eye surgeryEye surgeryMain
Open search
Eye surgery
Community hub
Eye surgery
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Eye surgery
Eye surgery
from Wikipedia
Eye surgery
Eye surgery in the Middle Ages
ICD-10-PCS08
ICD-9-CM08-16
MeSHD013508
OPS-301 code5-08...5-16
Ophthalmologic Surgeon, Ophthalmologist, Eye Surgeon
Occupation
Names
  • Physician
  • Surgeon
Occupation type
Specialty
Activity sectors
Medicine, surgery
Description
Education required
Fields of
employment
Hospitals, clinics

Eye surgery, also known as ophthalmic surgery or ocular surgery, is surgery performed on the eye or its adnexa.[1] 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.[2] It continues to be a widely practiced class of surgery, with various techniques having been developed for treating eye problems.

Preparation and precautions

[edit]

Since the eye is heavily supplied by nerves, anesthesia is essential. Local anesthesia is most commonly used. Topical anesthesia using lidocaine topical gel is often used for quick procedures. Since topical anesthesia requires cooperation from the patient, general anesthesia is often used for children, traumatic eye injuries, or major orbitotomies, and for apprehensive patients. The physician administering anesthesia, or a nurse anesthetist or anesthetist assistant with expertise in anesthesia of the eye, monitors the patient's cardiovascular status. Sterile precautions are taken to prepare the area for surgery and lower the risk of infection. These precautions include the use of antiseptics, such as povidone-iodine, and sterile drapes, gowns, and gloves.

Laser eye surgery

[edit]

Although the terms laser eye surgery and refractive surgery are commonly used as if they were interchangeable, this is not the case. Lasers may be used to treat nonrefractive conditions (e.g. to seal a retinal tear).[3] Laser eye surgery or laser corneal surgery is a medical procedure that uses a laser to reshape the surface of the eye to correct myopia (short-sightedness), hypermetropia (long-sightedness), and astigmatism (uneven curvature of the eye's surface). Importantly, refractive surgery is not compatible with everyone, and people may find on occasion that eyewear is still needed after surgery.[4]

Recent developments also include procedures that can change eye color from brown to blue.[5][6] Before proceeding with laser surgery, the eye specialist needs to certify that the patient is a suitable candidate for the surgery and there are several factors to be considered before doing laser surgery.[7]

Cataract surgery

[edit]
Cataract surgery, using a temporal approach phacoemulsification probe (in right hand) and "chopper" (in left hand) being done under operating microscope at a Navy medical center

A cataract is an opacification or cloudiness of the eye's crystalline lens due to aging, disease, or trauma that typically prevents light from forming a clear image on the retina. If visual loss is significant, surgical removal of the lens may be warranted, with lost optical power usually replaced with a plastic intraocular lens. Owing to the high prevalence of cataracts, cataract extraction is the most common eye surgery. Rest after surgery is recommended.[8]

Glaucoma surgery

[edit]

Glaucoma is a group of diseases affecting the optic nerve that results in vision loss and is frequently characterized by raised intraocular pressure. Many types of glaucoma surgery exist, and variations or combinations of those types can facilitate the escape of excess aqueous humor from the eye to lower intraocular pressure, and a few that lower it by decreasing the production of aqueous humor.

Canaloplasty

[edit]

Canaloplasty is an advanced, nonpenetrating procedure designed to enhance drainage through the eye's natural drainage system to provide sustained reduction of intraocular pressure. Canaloplasty uses microcatheter technology in a simple and minimally invasive procedure. To perform a canaloplasty, an ophthalmologist creates a tiny incision to gain access to a canal in the eye. A microcatheter circumnavigates the canal around the iris, enlarging the main drainage channel and its smaller collector channels through the injection of a sterile, gel-like material called viscoelastic.[clarification needed] The catheter is then removed and a suture is placed within the canal and tightened.[clarification needed] By opening up the canal, the pressure inside the eye can be reduced.[clarification needed][9][10][11][12]

Refractive surgery

[edit]

Refractive surgery aims to correct errors of refraction in the eye, reducing or eliminating the need for corrective lenses.

Corneal surgery

[edit]

Corneal surgery includes most refractive surgery, as well as:

Vitreoretinal surgery

[edit]
Vitrectomy

Vitreoretinal surgery includes:

  • Vitrectomy[20]
    • Anterior vitrectomy is the removal of the front portion of vitreous tissue. It is used for preventing or treating vitreous loss during cataract or corneal surgery, or to remove misplaced vitreous in conditions such as aphakia pupillary block glaucoma.
    • Pars plana vitrectomy or trans pars plana vitrectomy is a procedure to remove vitreous opacities and membranes through a pars plana incision. It is frequently combined with other intraocular procedures for the treatment of giant retinal tears, tractional retinal detachments, and posterior vitreous detachments.
  • Pan retinal photocoagulation is a type of photocoagulation therapy used in the treatment of diabetic retinopathy.[21]
  • Retinal detachment repair
    • Ignipuncture is an obsolete procedure that involves cauterization of the retina with a very hot, pointed instrument.[22]
    • A scleral buckle is used in the repair of a retinal detachment to indent or "buckle" the sclera inward, usually by sewing a piece of preserved sclera or silicone rubber to its surface.[23]
    • Laser photocoagulation, or photocoagulation therapy, is the use of a laser to seal a retinal tear.[21]
    • Pneumatic retinopexy
    • Retinal cryopexy, or retinal cryotherapy, is a procedure that uses intense cold to induce a chorioretinal scar and to destroy retinal or choroidal tissue.[24]
  • Macular hole repair
  • Partial lamellar sclerouvectomy[25]
  • Partial lamellar sclerocyclochoroidectomy
  • Partial lamellar sclerochoroidectomy
  • Posterior sclerotomy is an opening made into the vitreous through the sclera, as for detached retina or the removal of a foreign body.[26]
  • Radial optic neurotomy
  • Macular translocation surgery
    • through 360° retinotomy
    • through scleral imbrication technique

Eye muscle surgery

[edit]
Isolating the inferior rectus muscle
Disinserting the medial rectus muscle, after placing vicryl suture

With about 1.2 million procedures each year, extraocular muscle surgery is the third-most common eye surgery in the United States. [1] Archived 2016-08-18 at the Wayback Machine

  • Eye muscle surgery typically corrects strabismus and includes:[27][28]
    • Loosening or weakening procedures
      • Recession involves moving the insertion of a muscle posteriorly towards its origin.
      • Myectomy
      • Myotomy
      • Tenectomy
      • Tenotomy
    • Tightening or strengthening procedures
      • Resection
      • Tucking
      • Advancement is the movement of an eye muscle from its original place of attachment on the eyeball to a more forward position.
    • Transposition or repositioning procedures
    • Adjustable suture surgery is a method of reattaching an extraocular muscle by means of a stitch that can be shortened or lengthened within the first postoperative day, to obtain better ocular alignment.[29]

Oculoplastic surgery

[edit]

Oculoplastic surgery, or oculoplastics, is the subspecialty of ophthalmology that deals with the reconstruction of the eye and associated structures. Oculoplastic surgeons perform procedures such as the repair of droopy eyelids (blepharoplasty),[30] repair of tear duct obstructions, orbital fracture repairs, removal of tumors in and around the eyes, and facial rejuvenation procedures including laser skin resurfacing, eye lifts, brow lifts, and even facelifts. Common procedures are:

Eyelid surgery

[edit]

Orbital surgery

[edit]
  • Orbital reconstruction or ocular prosthetics (false eyes)
  • Orbital decompression is used for Grave's disease, a condition (often associated with overactive thyroid problems) in which the eye muscles swell. Because the eye socket is bone, the swelling cannot be accommodated and as a result, the eye is pushed forward into a protruded position. In some patients, this is very pronounced. Orbitial decompression involves removing some bone from the eye socket to open up one or more sinuses and so make space for the swollen tissue and allowing the eye to move back into normal position.

Other oculoplastic surgery

[edit]

Surgery involving the lacrimal apparatus

[edit]

Eye removal

[edit]
  • An enucleation is the removal of the eye leaving the eye muscles and remaining orbital contents intact.[37]
  • An evisceration is the removal of the eye's contents, leaving the scleral shell intact. Usually performed to reduce pain in a blind eye.[38]
  • An exenteration is the removal of the entire orbital contents, including the eye, extraocular muscles, fat, and connective tissues; usually for malignant orbital tumors.[39]

Other surgery

[edit]

Many of these described procedures are historical and are not recommended due to a risk of complications. Particularly, these include operations done on ciliary body in an attempt to control glaucoma, since highly safer surgeries for glaucoma, including lasers, nonpenetrating surgery, guarded filtration surgery, and seton valve implants have been invented.

References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia
from Grokipedia
Eye surgery, also known as ophthalmic or ocular surgery, refers to any surgical procedure performed on the eye or its surrounding tissues (adnexa) to diagnose, treat, or prevent eye conditions, improve vision, or repair injuries. These operations are typically carried out by ophthalmologists, medical doctors who specialize in comprehensive eye and vision care, including surgical interventions after extensive training in both medical and surgical aspects of . Common goals include correcting refractive errors like nearsightedness or , removing diseased tissues such as clouded lenses, or addressing structural issues like glaucoma-related pressure buildup. Among the most prevalent types of eye surgery is cataract surgery, which involves removing the eye's natural lens when it becomes cloudy and replacing it with an artificial (IOL) to restore clear vision; over 25 million such procedures are performed worldwide each year and about 4 million in the United States as of 2024. Refractive surgeries, such as (laser-assisted in situ keratomileusis), use lasers to reshape the and correct vision problems without the need for or contacts; approximately 800,000 such laser refractive procedures are conducted annually in the U.S. as of 2024. Other notable procedures include glaucoma surgery to reduce and prevent optic nerve damage, corneal transplants (keratoplasty) to replace damaged corneal tissue, affecting about 85,000 patients annually in the U.S. as of 2024, and vitrectomy to remove vitreous gel and repair retinal issues. Less common but significant interventions encompass strabismus surgery to realign eye muscles, for eyelid corrections, and enucleation or evisceration in cases of severe trauma or cancer. Overall, advancements in laser technology, such as femtosecond lasers, and microsurgery, including AI-assisted techniques, have made eye surgeries safer and more precise as of 2025, significantly enhancing for millions by preserving or restoring vision.

Preoperative and Perioperative Care

Preoperative Assessment and Preparation

The preoperative assessment for eye surgery begins with a comprehensive to evaluate ocular health and determine surgical suitability. This includes to assess the eye's focusing ability, slit-lamp biomicroscopy to inspect the anterior segment for abnormalities such as corneal irregularities or lens opacities, tonometry to measure , funduscopy to examine the and for pathologies like tears or degeneration, and to map the corneal surface curvature and detect irregularities. These evaluations help identify conditions that could compromise surgical outcomes or require additional interventions. A thorough medical history review is essential to identify systemic conditions that may influence surgical risks or healing. Conditions such as , particularly insulin-dependent cases, can affect and increase complication risks, necessitating optimized glycemic control prior to surgery. Autoimmune diseases, including or , are assessed for their potential to impair corneal healing or exacerbate postoperative inflammation, though studies indicate generally favorable outcomes with careful management. is specifically evaluated, as it can distort preoperative measurements and heighten postoperative discomfort; assessments include and Schirmer testing to quantify tear production and stability. Patient education forms a critical part of preparation, focusing on lifestyle adjustments to optimize the ocular surface. Patients are advised to discontinue wear to allow corneal shape stabilization, typically 1 week for soft lenses and 3-4 weeks for rigid gas-permeable lenses. Certain medications, such as herbal supplements with anticoagulant properties (e.g., or ), may need to be paused to minimize bleeding risks, while prescription blood thinners are often continued under physician guidance due to the low-bleeding nature of most eye procedures. The informed consent process involves detailed discussion of procedure-specific expectations, potential risks, benefits, and alternatives, ensuring patients understand outcomes like visual improvement or possible limitations. For vision correction surgeries, baseline measurements include pupillometry to gauge pupil diameter under varying light conditions, aiding in aberration risk assessment, and tear film evaluation to establish preoperative stability.

Anesthesia Options and Precautions

Topical anesthesia is commonly employed for superficial eye procedures such as , utilizing agents like proparacaine drops applied directly to the and . This method provides rapid onset within 30 seconds to 1-2 minutes and a duration of 10-20 minutes, sufficient for brief interventions without inducing akinesia. It minimizes systemic risks and is particularly advantageous for patients on anticoagulants, as it avoids injection-related bleeding. Local anesthesia, administered via peribulbar or retrobulbar injections, is standard for intraocular surgeries like extraction and procedures. Peribulbar blocks involve extraconal injection using a 25-27 gauge needle (less than 1.25 inches) inserted inferotemporally or medially, with volumes of 6-12 mL to achieve analgesia and partial akinesia over 5-10 minutes. Retrobulbar techniques use a 23-25 gauge needle (up to 1.5 inches) for intraconal delivery of 2-4 mL, providing more complete akinesia (approximately 85%) but carrying higher risks of complications like globe perforation. Both require negative aspiration to avoid vascular injection and patient cooperation during transconjunctival or approaches. General anesthesia is reserved for complex cases, including pediatric surgeries, vitreoretinal interventions, or orbital procedures where patient movement must be fully controlled. It involves deep to prevent intraoperative motion, with standard monitoring including for oxygenation, for ventilation, for circulation, and assessment. Agents like and are preferred as they help lower (IOP). Precautions are essential for high-risk patients, such as those with narrow anterior chamber angles prone to angle-closure glaucoma or bleeding disorders like coagulopathies. In such cases, regional blocks may be avoided if axial length exceeds 26 mm or active infection is present, and anticoagulants can often continue within therapeutic ranges. Prophylactic measures include preoperative application of antiseptic solutions like 5% and antibiotic drops (e.g., fluoroquinolones), alongside drops to mitigate risks. Intraoperative monitoring focuses on maintaining IOP below 25 mmHg during injections to prevent complications like hemorrhage, with continuous assessment using tonometry or indirect methods.

Postoperative Recovery and Complications

Following eye surgery, patients typically adhere to standardized recovery protocols to promote healing and minimize risks. These include wearing a protective eye shield, particularly at night, to prevent accidental trauma during sleep. Antibiotic and steroid eye drops are commonly prescribed, with a tapering regimen over approximately four weeks to combat infection and reduce inflammation; for instance, topical antibiotics like gatifloxacin are used for one week, while corticosteroids such as prednisolone acetate may continue for up to four weeks, often combined with nonsteroidal anti-inflammatory drugs (NSAIDs) like bromfenac to manage potential cystoid macular edema. Activity restrictions are essential, such as avoiding rubbing the eyes, heavy lifting, or strenuous exercise for at least one week, and refraining from swimming or hot tubs for two weeks to reduce infection risk. Common postoperative complications are often transient and resolve with conservative management. Blurred vision and photophobia frequently occur in the initial days to weeks due to corneal or residual , affecting most patients temporarily. Subconjunctival hemorrhage, appearing as a red patch on the eye's surface, is benign and typically resolves within two weeks without intervention. Dry eyes represent another prevalent issue, particularly after refractive procedures, with symptoms like discomfort and sensation impacting 20-40% of cases in the first month, often managed with or punctal plugs. More serious complications, though rare, require prompt recognition and intervention to preserve vision. , an intraocular infection, has an incidence of 0.04-0.3% following procedures like , presenting with severe pain, vision loss, and ; diagnosis involves clinical examination and vitreous tap, with treatment entailing immediate intravitreal injection of antibiotics such as and ceftazidime, often supplemented by systemic therapy or pars plana vitrectomy. Elevated intraocular pressure (IOP) can arise from steroid use or inflammation, occurring in 1-10% of cases postoperatively, particularly those exceeding 30 mmHg, monitored via tonometry and managed with topical beta-blockers or inhibitors if needed. Corneal , characterized by hazy vision and stromal thickening, is usually self-limited but may necessitate hypertonic saline drops in persistent cases. Follow-up care is structured to monitor healing and detect issues early, typically including a day-1 visit to assess for immediate complications like or IOP spikes, a week-1 appointment for suture evaluation and drop adjustment, and a month-1 check focusing on testing via to confirm refractive stability. These visits allow for slit-lamp examination and fundus evaluation to ensure proper wound closure and . Long-term outcomes emphasize tracking refractive stability over 6-12 months, during which vision typically stabilizes as epithelial remodeling completes; for refractive surgeries, which generally remain stable beyond one year, with most patients achieving enduring correction. Ongoing monitoring helps identify late-onset issues like posterior capsule opacification, treatable with YAG capsulotomy if needed.

Refractive Surgery

Laser-Based Refractive Procedures

Laser-based refractive procedures utilize and lasers to reshape the , correcting common refractive errors such as , hyperopia, and by altering the corneal to improve focus on the . These techniques emerged as minimally invasive alternatives to or contact lenses, offering rapid visual recovery and high patient satisfaction rates, with over 90% achieving uncorrected of 20/20 or better in suitable candidates. The , which emits light to precisely ablate corneal tissue without thermal damage, forms the core of ablation-based methods, while lasers enable precise tissue cutting for flap or lenticule creation. Laser-assisted in situ () involves creating a thin l flap, typically 100-120 μm thick, using a femtosecond laser, followed by of the underlying stroma to reshape the . This procedure corrects up to -12 diopters (D), hyperopia up to +6 D, and up to 6 D, with the flap repositioned to promote quick healing and minimal discomfort. 's popularity stems from its outpatient nature, with vision stabilizing within 24 hours, though it requires sufficient corneal thickness to avoid complications like . Photorefractive keratectomy (PRK) is a surface technique that removes the mechanically or with laser assistance, followed by reshaping of the exposed and anterior stroma, without creating a flap. It is particularly suitable for patients with thin corneas or those at risk for flap-related issues, as it preserves more stromal integrity. Epithelial healing typically occurs in 3-5 days, during which patients experience moderate managed by oral analgesics, topical medications, and therapeutic bandage contact lenses to protect the surface and reduce discomfort. Visual recovery is slower than , often taking 1-2 weeks, but long-term outcomes are comparable for low to moderate refractive errors. Small incision lenticule extraction () employs a femtosecond to create an intrastromal lenticule within the , which is then extracted through a small 2-4 mm incision, avoiding flap creation and minimizing postoperative dry eye risk. Approved by the FDA in 2016 for from -1 D to -10 D and in 2018 for up to 3 D, offers a minimally invasive option with biomechanical stability benefits over traditional . This procedure gained widespread adoption post-approval due to its flapless design, which reduces higher-order aberrations and supports faster return to physical activities. Advanced variants like topography-guided and wavefront-optimized enhance customization for irregular by integrating maps or wavefront aberrometry data to generate personalized profiles. Topography-guided treatments regularize corneal irregularities through targeted , improving visual quality in eyes with prior or , while wavefront-optimized profiles preserve the cornea's natural asphericity to minimize induced spherical aberrations. These methods achieve superior contrast sensitivity and reduced halos compared to conventional . The foundation of these procedures traces to the FDA's approval of the for in 1995, with broader indications following in 1999, marking the shift from experimental to standard refractive care. By 2025, integrations of in preoperative planning have refined personalized treatments, using algorithms to analyze corneal and predict optimal patterns, thereby further reducing higher-order aberrations and enhancing outcomes for complex cases.

Implant and Lens-Based Refractive Procedures

Implant and lens-based refractive procedures involve the surgical placement of artificial lenses or modification of the eye's natural lens to correct refractive errors, offering alternatives to corneal laser surgeries for patients with high degrees of , hyperopia, or who may not be ideal candidates for surface techniques. These methods preserve the natural lens in phakic procedures or replace it in aphakic exchanges, providing reversible or customizable options that can achieve spectacle independence in suitable cases. Unlike laser-based approaches, which reshape the and are often preferred for mild refractive errors, these intraocular interventions target deeper optical structures for more profound corrections. The Implantable Collamer Lens (ICL), such as the EVO Visian ICL, is a (IOL) made of a biocompatible copolymer, surgically inserted into the posterior chamber behind the iris to correct moderate to high ranging from -3 to -20 diopters (D), including associated up to 4 D. Approved by the U.S. in its EVO configuration in March 2022, this lens features a central aquaport to facilitate aqueous humor flow, reducing the need for peripheral iridotomies and minimizing risks like pupillary block. The procedure is reversible, as the lens can be explanted if necessary, and postoperative vault—the space between the lens and natural crystalline lens—is monitored using anterior segment ultrasound or to ensure safety and prevent complications such as formation or elevated . Refractive lens exchange (RLE) entails the removal of the eye's clear crystalline lens and implantation of a custom to address or extreme hyperopia exceeding +4 D, mimicking techniques but in non-cataractous eyes. This approach is particularly beneficial for older patients seeking multifocal or extended-depth-of-focus IOLs to reduce dependence on reading glasses, with studies reporting high rates of uncorrected near and distance improvement. However, RLE carries risks including , with an incidence of approximately 1-2%, roughly double that observed after standard cataract extraction due to vitreous changes and . Intracorneal ring segments, such as Intacs, consist of biocompatible polymethylmethacrylate segments implanted into channels within the mid-peripheral corneal stroma to flatten the central and regularize its shape in mild cases of , thereby improving and without tissue ablation. FDA-approved for in 2004, these segments act as supportive arcs that enhance corneal stability, delaying or avoiding the need for in early-stage disease, with visual gains often evident within months and minimal complications like segment extrusion. Light-adjustable lenses (LAL) represent an innovative IOL implanted during surgery and subsequently refined through non-invasive (UV) light treatments to fine-tune refractive outcomes, allowing adjustments in spherical power and by up to 2 in 0.25 increments over a period of up to 3 months postoperatively. FDA-approved in November 2017, the uses photosensitive material that polymerizes under controlled UV exposure in an office setting, followed by a final "lock-in" treatment to stabilize the lens, enabling personalized correction for residual errors and reducing enhancement surgeries. Clinical data indicate that over 80% of patients achieve 20/20 or better uncorrected distance vision after adjustments, particularly advantageous for those with irregular corneas or unpredictable healing. Patient selection for these procedures emphasizes anatomical and ocular health criteria to minimize risks. Contraindications include a shallow anterior chamber depth of less than 3 mm, which increases the likelihood of endothelial touch and corneal , and an endothelial cell count below 2000 cells/mm², as implantation can accelerate cell loss over time. Additional evaluations involve comprehensive biometry, , and dilated fundus exams to exclude conditions like or retinal pathology that could exacerbate postoperative complications.

Anterior Segment Surgery

Cataract Surgery

Cataract surgery involves the removal of the opaque natural lens of the eye and its replacement with an artificial intraocular lens (IOL) to restore clear vision, representing the most frequently performed surgical procedure globally. This intervention addresses age-related clouding of the lens, which scatters light and impairs visual acuity. The standard approach preserves the lens capsule to support the IOL, minimizing trauma and promoting rapid recovery. Performed under local or topical anesthesia, the surgery typically lasts 15-30 minutes per eye and boasts high success rates, with over 95% of patients achieving improved vision postoperatively. Epidemiologically, cataracts affect more than 50% of individuals over age 80 , with similar prevalence patterns observed globally due to aging populations. Worldwide, approximately 28 million procedures are conducted annually as of 2025, driven by increasing and improved surgical access in developing regions. The condition disproportionately impacts older adults, with risk factors including ultraviolet exposure, , and , underscoring the procedure's role in preventing vision loss among the elderly. The predominant technique, , employs ultrasonic energy to emulsify and aspirate the lens nucleus through a small clear corneal incision of 2.2-2.8 mm. This method begins with a continuous curvilinear capsulorhexis, creating a 5-6 mm opening in the anterior lens capsule to allow safe lens removal while maintaining capsular integrity. Hydrodissection follows, injecting to separate the lens nucleus from the capsule, facilitating rotation and extraction with minimal zonular stress. This micro-incision approach enables self-sealing wounds, reduces induction, and supports outpatient recovery. For dense or brunescent s where risks thermal injury or incomplete fragmentation, extracapsular extraction (ECCE) serves as an alternative. In ECCE, a larger 10-12 mm scleral or corneal incision allows manual expression of the intact nucleus after capsulotomy and cortical cleavage, preserving the posterior capsule for IOL placement. Though requiring sutures and longer healing than , ECCE remains valuable in resource-limited settings or complicated cases, with comparable visual outcomes when performed by experienced surgeons. Following lens removal, an IOL is implanted into the capsular bag to replace the focusing power of the natural lens. Monofocal IOLs provide sharp vision at a single distance, typically optimized for distance to reduce reliance on glasses for far tasks. Multifocal IOLs address by offering multiple focal points for near, intermediate, and distance vision, while toric IOLs correct through asymmetric optics, improving uncorrected acuity in irregular corneas. By 2025, extended-depth-of-focus (EDOF) IOLs have advanced with diffractive or refractive designs that elongate the focal range, significantly reducing dysphotopsia such as halos and glare compared to traditional multifocals, enhancing patient satisfaction in low-light conditions. A key complication is posterior capsule opacification (PCO), occurring in 20-50% of cases due to proliferation of lens epithelial cells on the posterior capsule, leading to months to years postoperatively. PCO manifests as fibrous or pearl-like opacities, with higher rates in younger patients or those with . It is effectively treated via neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy, a non-invasive outpatient procedure that creates a central opening in the opacified capsule, restoring clarity in over 90% of cases with minimal risk. Postoperative care may include and drops to prevent and .

Glaucoma Surgery

Glaucoma surgery encompasses a range of procedures designed to reduce (IOP) by enhancing the outflow of aqueous humor through the eye's natural or augmented drainage pathways, thereby slowing the progression of damage in patients with open-angle or other forms of . These interventions target structures such as the , , or subconjunctival space, often as a step beyond medical or laser therapies when IOP remains uncontrolled. Traditional approaches involve creating new filtration routes, while newer techniques prioritize minimal tissue disruption to lower complication risks and preserve options for future treatments. Success is typically measured by achieving target IOP levels, such as below 21 mmHg, with reduced need for medications. Trabeculectomy remains a cornerstone incisional procedure for moderate to advanced , involving the creation of a partial-thickness scleral flap to form a filtering bleb under the , allowing aqueous humor to drain from the anterior chamber into the subconjunctival space. To mitigate postoperative scarring that could obstruct , antimetabolites like mitomycin-C are applied intraoperatively, typically at concentrations of 0.2-0.4 mg/mL for 2-3 minutes, which inhibits proliferation and enhances long-term patency. Clinical outcomes demonstrate qualified success rates of 70-90% in maintaining IOP below 21 mmHg at 1-5 years post-surgery, though rates decline over time due to bleb or encapsulation, with adjunctive needling revisions often required in 20-30% of cases. This procedure is particularly effective for primary open-angle but carries risks of hypotony, infection, or bleb leaks if scarring is inadequately controlled. For refractory cases where prior has failed or in eyes with conjunctival scarring, tube shunt implantation offers an alternative by diverting aqueous humor via a tube inserted into the anterior chamber and connected to a valved (e.g., Ahmed) or non-valved (e.g., Baerveldt) episcleral plate that promotes posterior drainage. The Ahmed valve provides immediate flow regulation to prevent early hypotony, while the Baerveldt requires temporary tube ligation with an absorbable suture, which is released 4-6 weeks postoperatively to initiate drainage and avoid excessive pressure drops. Long-term success rates reach 70-80% for IOP control under 21 mmHg at 2-5 years, with the Baerveldt often showing superior pressure reduction in multicenter trials, though higher rates of disturbances and tube erosion necessitate careful patient selection. These devices are ideal for neovascular or uveitic but may require anticoagulation management perioperatively.00365-5/abstract) Minimally invasive glaucoma surgery (MIGS) represents a toward ab interno procedures performed concurrently with extraction, utilizing microstents to bypass or enhance trabecular outflow with minimal conjunctival disruption. The iStent inject, a pair of heparin-coated spurs, is inserted into the to facilitate direct access to , achieving an average IOP reduction of 20-25% and medication decrease from 1-2 drops at 12-24 months. Similarly, the Microstent, a nitinol scaffold spanning 90 degrees of the canal, extends outflow pathways and yields 25-30% IOP lowering with up to 60% medication reduction, as evidenced in randomized trials, alongside low complication rates of 1-5% for transient or IOP spikes. These devices suit mild to moderate , offering rapid recovery and conjunctival preservation for potential future filtering surgery.00853-3/fulltext) Canaloplasty provides a non-perforating alternative that restores physiologic outflow by viscodilating using a microcatheter to inject viscoelastic material circumferentially, followed by tensioning a 10-0 suture looped 360 degrees within the canal to maintain dilation and collector channel patency. This ab externo approach avoids full-thickness penetration of the trabeculo-Descemet's membrane, reducing risks of hypotony or choroidal effusion compared to , while preserving overlying for subsequent interventions. Postoperative IOP reductions average 25-35% at 1-2 years, with success rates of 70-80% in primary open-angle , and minimal complications such as microhyphema in under 10% of cases, making it suitable for patients seeking suture-tensioned enhancement without bleb formation. As of 2025, endocyclophotocoagulation (ECP) has gained prominence as an endoscopic technique for mild to moderate , delivering via a probe inserted through a clear corneal incision to selectively ablate 120-180 degrees of the processes, thereby reducing aqueous humor production while visualizing treatment to spare non-target tissue. Integrated with , ECP achieves 20-30% IOP lowering and medication reduction in 70-85% of cases at 1-5 years, with low rates of persistent or hypotony (under 5%), positioning it as a versatile option for combined procedures in refractory or pediatric . Recent studies highlight its efficacy in malignant management post-trabeculectomy, underscoring evolving applications in precision outflow modulation.

Corneal Surgery

Corneal surgery encompasses a range of procedures aimed at treating diseases affecting the , the transparent outer layer of the eye, to restore its clarity, structure, and function. These interventions are primarily indicated for conditions such as corneal dystrophies, , trauma, and infections that lead to opacity or irregularity. Unlike procedures targeting the lens or aqueous humor outflow, corneal surgery focuses on replacing or reshaping corneal tissue to improve vision and prevent complications like . The most common approaches involve transplantation techniques, which have evolved from full-thickness replacements to more selective partial-thickness methods to minimize risks and enhance recovery. Penetrating keratoplasty (PK), also known as full-thickness , involves the complete removal and replacement of the diseased host with a donor . The procedure typically uses a to create a circular incision in the host , with diameters ranging from 7.5 to 8.5 mm, followed by suturing the donor graft using 16 interrupted 10-0 sutures or a continuous suture to secure alignment and reduce . These sutures are usually left in place for 12 to 18 months to allow , after which selective removal may be performed to adjust . Rejection risk in low-risk cases stands at 10-20%, primarily managed with topical corticosteroids, though higher in vascularized or previously rejected grafts. Endothelial keratoplasty techniques, such as Descemet stripping endothelial keratoplasty (DSEK) or Descemet stripping automated endothelial keratoplasty (DSAEK), address in conditions like by replacing only the inner layers of the , including and , while preserving the patient's anterior stroma. Performed through a small 2.8-3.2 mm incision, the procedure involves stripping the diseased and injecting a pre-cut donor lenticule, which is then unfolded and attached using an air or gas . Visual recovery is faster than with PK, typically achieving functional vision within 3-6 months, with endothelial cell loss around 25-40% in the first year. Descemet membrane endothelial keratoplasty (DMEK), a thinner variant, replaces only the and via a similar small incision, offering even quicker recovery—often 1-3 months to reach 20/25 or better vision in 60-80% of cases—and lower long-term endothelial loss (around 30-40% at 5 years) compared to DSEK/DSAEK. Lamellar keratoplasty includes anterior lamellar keratoplasty (ALK), which replaces the superficial corneal layers for stromal opacities or scars while preserving the deeper , and deep anterior lamellar keratoplasty (DALK), a preferred option for advanced . In DALK, the anterior stroma is dissected and removed down to using techniques like manual air dissection or visco-dissection, followed by overlaying a donor stroma; the endothelium remains intact, reducing rejection risk to under 5% and eliminating the need for intraocular manipulation. ALK is less commonly used today but suits superficial pathologies, maintaining endothelial health to support graft longevity exceeding 10-15 years in keratoconus cases. These partial-thickness methods lower intraoperative open-sky time and postoperative complications compared to PK. Keratotomy procedures involve precise incisions to reshape the without transplantation. Radial keratotomy (RK), a historical refractive technique introduced in the and popularized in the U.S. in 1978, corrected by making 4-8 radial incisions (extending 90% of corneal depth) from a central optical zone of 3-4 mm to the periphery, flattening the central ; it is now rarely performed due to diurnal fluctuations and hyperopic shifts over time. Astigmatic keratotomy (AK) employs paired arcuate or transverse incisions, often at a 7-8 mm optical zone, to reduce post-transplant or post-cataract greater than 2 diopters, with nomograms guiding incision length and axis for targeted correction. These incision-based methods have largely been supplanted by procedures but remain useful adjuncts in select cases. In the United States, approximately 87,000 corneal transplants are performed annually as of 2023, with projections indicating sustained or slightly increased volume by 2025 due to rising demand from aging populations and conditions like . Tissue selection often incorporates (HLA) typing, particularly for high-risk recipients with vascularization or prior rejections, to minimize immune mismatch, though routine matching shows limited benefit in low-risk first-time grafts.

Posterior Segment Surgery

Vitreoretinal Surgery

Vitreoretinal surgery focuses on the management of pathologies involving the vitreous humor and in the posterior segment of the eye, utilizing minimally invasive techniques to restore visual function. The cornerstone procedure is vitrectomy (PPV), which allows surgeons to access and remove the vitreous gel through small incisions in the region of the , minimizing trauma to the lens and anterior structures. Common indications for PPV include , where fibrovascular proliferation pulls the away from the underlying tissue, and vitreous hemorrhage, often resulting from neovascularization in proliferative that obscures vision. Anatomic success rates for retinal reattachment following PPV in these cases typically range from 85% to 95%, with primary success (single surgery) around 94% in systematic reviews of tractional detachments. The PPV procedure employs 23- to 27-gauge trocars and cannulas for instrument insertion, enabling sutureless surgery with reduced operative time and postoperative inflammation compared to larger 20-gauge systems. Vitreous removal is achieved using a vitrectomy probe that cuts and aspirates the gel, often followed by tamponade to support retinal reattachment: expansile gases like sulfur hexafluoride (SF₆) provide support for 2 to 3 weeks, while silicone oil offers longer-term tamponade, typically maintained for 2 to 6 months until removal. During PPV for proliferative diabetic retinopathy, endolaser photocoagulation is commonly applied intraoperatively to seal retinal leaks, ablate neovascularization, and prevent further hemorrhage, using curved or straight probes to target peripheral retina. For conditions involving macular distortion, such as s or macular holes, PPV includes membrane peeling to relieve traction on the . Surgeons use fine or scrapers to elevate the epiretinal membrane or internal limiting membrane (ILM), often after staining with dye at low concentrations (0.06% to 0.15%) to enhance visibility of these transparent tissues. Instrumentation has evolved significantly, with wide-angle viewing systems, chandelier lighting for bimanual techniques, and 3D visualization platforms—such as those integrated with heads-up displays—improving surgical precision and ergonomics by 2025. These advancements facilitate safer removal of vitreous opacities and precise retinal interventions, contributing to the high success rates observed in contemporary practice.

Retinal Detachment and Macular Surgery

Retinal detachment surgery primarily addresses rhegmatogenous (RRD), where fluid passes through retinal breaks into the subretinal space, separating the neurosensory from the , while macular surgery targets disorders like macular holes and historical submacular pathology. These procedures aim to reattach the and restore macular function, often combining external support, gas , or membrane peeling with adjunctive techniques such as or photocoagulation. Success is evaluated by anatomical reattachment and functional outcomes via (OCT) and assessments. The incidence of RRD is approximately 12-14 cases per 100,000 individuals annually, with a lifetime of about 1 in 300, predominantly affecting myopic patients, males, and those aged 40-60 years. increases post-, with rates of 0.5-2% in the first year, particularly in eyes with or prior trauma. Macular holes, often idiopathic and affecting individuals over 60, have an incidence of about 7.8 per 100,000, leading to central vision loss if untreated. Scleral buckling involves placing a encircling band or segmental around the globe to indent the , supporting retinal breaks and closing them via or , thereby relieving vitreous traction in RRD. This external approach is particularly effective for phakic, uncomplicated detachments without proliferative vitreoretinopathy, achieving single-surgery anatomical success rates of 85-95%. Complications include extrusion or induced , but it preserves the lens and avoids intraocular manipulation in suitable cases. Pneumatic retinopexy is an outpatient procedure for superior RRD with limited breaks, involving intravitreal injection of an expandable gas bubble, such as perfluoropropane (C3F8), to tamponade the against the buckle while or seals the break. The gas bubble, lasting 55-70 days, allows natural resorption of subretinal fluid, with single-procedure success rates of 60-80% and overall reattachment exceeding 90% upon adjunctive interventions. It offers rapid recovery and lower cost compared to more invasive methods but requires patient positioning and is contraindicated in inferior detachments. may serve as an adjunct for complex cases. Macular hole surgery typically employs pars plana vitrectomy followed by internal limiting membrane (ILM) peeling to relieve tangential traction, with C3F8 gas tamponade to appose hole edges and promote gliosis-mediated closure, confirmed by OCT. For stage 3-4 full-thickness macular holes (diameter >250 μm), closure rates reach 90-100%, with visual improvement in 70-80% of cases, though larger holes (>400 μm) benefit more from peeling. Face-down positioning is often advised postoperatively for 3-7 days to optimize outcomes. Submacular surgery, historically used to excise (CNV) membranes in via retinotomy and membrane removal, achieved variable visual stabilization but carried risks of retinal damage and hemorrhage. Its use has declined since the advent of (anti-VEGF) injections in the early 2000s, which offer non-invasive CNV regression with better safety profiles. By 2025, robotic assistance enhances precision in related subretinal procedures, such as delivery or membrane manipulation, reducing and improving stability in vitreoretinal interventions.

Oculoplastic and Adnexal Surgery

Eyelid and Orbital Surgery

Eyelid and orbital surgery encompasses a range of procedures aimed at correcting functional impairments, restoring , and addressing pathological conditions of the s and the bony surrounding the eye. These interventions are crucial for managing issues such as lid malpositions that threaten ocular surface integrity, orbital crowding from inflammatory diseases, and neoplastic growths that compromise tissue structure. Performed by oculoplastic surgeons, these operations prioritize preservation of visual function while minimizing complications like scarring or . Blepharoplasty is a common procedure for addressing excess skin and fat in the , often indicated for ptosis or , which can obstruct vision or cause discomfort. In upper eyelid blepharoplasty, an incision along the natural eyelid crease, typically 2 to 3 cm in , is made to remove redundant skin and orbicularis muscle, along with protruding fat, thereby elevating the lid and improving the . For lower eyelid cases, a transconjunctival approach accesses the orbital fat through the inner conjunctival surface, avoiding external scarring and reducing risks of . This technique is particularly effective for functional restoration in patients with significant , as supported by guidelines from the American Academy of Ophthalmology. Repairs for malpositions, such as and , focus on realigning the margin to protect the from exposure keratopathy. repair often involves tarsal fracture techniques or wedge resection of the tarsus to evert the lashes and tighten the posterior lamella, preventing and ulceration. For , the lateral tarsal strip procedure shortens the eyelid by excising a lateral wedge and reattaching the tarsus to the orbital rim, restoring support and apposition to the . These methods, including combined wedge resections, yield high success rates in involutional cases by addressing horizontal laxity and vertical vector imbalances. Orbital decompression surgery is primarily employed for thyroid eye disease, where inflammatory expansion of and fat causes proptosis and compressive . The procedure involves removing sections of the orbital walls, typically the medial wall (ethmoidal lamina papyracea) and inferior floor (adjacent to the and sphenoid), to expand the orbital volume and alleviate pressure. This results in an average proptosis reduction of 3-4 mm, improving eye position and reducing risks of exposure or vision loss. Balanced approaches, combining bony and fat removal, optimize outcomes while limiting . Tumor excision in the eyelid region, particularly for —the most prevalent malignancy—relies on Mohs micrographic surgery to achieve clear margins with maximal tissue sparing. This layered excision technique examines 100% of the tumor periphery under microscopy, ideal for the anatomically sensitive periocular area where recurrence risks are high. Post-excision reconstruction employs local flaps, such as the Hughes tarsoconjunctival flap, which advances upper lid tarsus and conjunctiva to rebuild the posterior lamella of full-thickness lower lid defects, ensuring structural integrity and lid function. Recent advancements as of 2025 emphasize endoscopic techniques in orbital to enhance precision and reduce morbidity. Transorbital neuroendoscopic approaches allow minimally invasive access to deep orbital structures, minimizing external incisions and scarring while facilitating decompression or . Innovations like periosteal suturing during endoscopic decompression further stabilize tissues and improve proptosis correction with lower complication rates. These methods represent a shift toward outpatient, scar-minimizing interventions for complex orbital pathologies.

Lacrimal Apparatus Surgery

Lacrimal apparatus surgery encompasses a range of procedures aimed at addressing disorders of tear production and drainage, primarily involving the , puncta, canaliculi, , and . These interventions treat conditions such as epiphora (excessive tearing), , and infections resulting from obstruction or inflammation in the lacrimal system. Common indications include congenital (CNLDO), which affects approximately 5-20% of newborns and often resolves spontaneously but requires intervention in persistent cases, and acquired obstructions leading to epiphora in adults, with an incidence of about 20 per 100,000 population. Post-surgical complications, such as epiphora occurring in 5-10% of cases following due to iatrogenic canalicular damage, also necessitate these procedures. Eyelid malpositions can contribute to secondary lacrimal obstruction by altering tear flow dynamics. Probing and is a minimally invasive first-line treatment for CNLDO in infants, typically performed under between 6 and 12 months of age if conservative measures like fail. The procedure involves dilating the punctum, passing a probe through the canaliculi to the to disrupt any membranous obstruction (often at the valve of Hasner), and irrigating with saline to clear debris and confirm patency. Success rates exceed 90% with the initial probing, rising to 96% after a second attempt if needed, making it highly effective for simple distal obstructions. For more complex or acquired obstructions causing chronic epiphora or , (DCR) creates a surgical bypass between the and . External DCR involves a incision medial to the medial to access the lacrimal sac and bone, followed by and mucosal , often with silicone maintained for 3-6 months to prevent scarring. Endoscopic DCR, performed transnasally under general or , avoids external scarring and achieves comparable outcomes. Both approaches yield success rates of 90-95% in symptom resolution, with endoscopic variants showing 82-98% efficacy in recent studies, though external DCR remains the gold standard for severe cases. Interventions for canalicular and punctal disorders include punctal plugs and canalicular repair. Silicone punctal plugs are inserted into the puncta to occlude tear drainage partially or fully, providing relief for aqueous-deficient dry eye, such as in Sjögren's syndrome, where dysfunction leads to reduced tear production affecting up to 95% of patients. Temporary plugs can be removed if over-drainage occurs, while permanent options suit chronic cases. For traumatic or iatrogenic canalicular lacerations or stenosis, microsurgical repair reapproximates the severed ends using fine sutures under magnification, often with silicone stenting to maintain lumen patency during healing; success depends on timely intervention within hours of injury. In severe, irreparable canalicular stenosis, a Jones tube—a glass or conduit—is implanted to bypass the upper lacrimal system, connecting the conjunctival fornix directly to the , with aiding initial stabilization. Lacrimal gland procedures, such as or dacryoadenectomy, target tumors, inflammatory conditions, or severe dry eye. involves an anterior orbitotomy to sample tissue for histopathological diagnosis, essential for distinguishing benign from malignant lesions like or , while preserving gland function through superficial excision when possible. In Sjögren's syndrome, confirms lymphocytic infiltration but is less common than minor due to lower morbidity; it aids in diagnosing autoimmune dry eye affecting tear secretion. Dacryoadenectomy, partial or total removal, is reserved for irreparable tumors or chronic inflammation unresponsive to , with efforts to minimize postoperative by sparing viable tissue.

Eye Muscle Surgery

Eye muscle surgery adjusts the to realign the eyes, primarily treating —a condition where the eyes fail to work together due to muscle imbalance—and occasionally , an involuntary eye oscillation. These procedures enhance eye coordination, reduce double vision, and support visual development by promoting binocular fusion. In cases, surgery targets the six to correct deviations like (inward turn) or (outward turn), while for , techniques like the Kestenbaum-Anderson procedure recess and resect horizontal muscles to shift the null point—the gaze position of minimal oscillation—to primary gaze, thereby correcting associated head postures greater than 20 degrees. A standard approach for is the recession-resection procedure, performed under general anesthesia on one or both eyes. The medial rectus muscle is detached from its insertion and reattached 4-6 mm posteriorly on the (recession) to weaken its inward pull, while the antagonist lateral rectus is shortened by resecting 3-5 mm of its and reattaching it to its original site (resection) to enhance outward movement. This combined adjustment typically corrects 15-25 prism diopters of deviation per operated eye, with dosing tailored to preoperative measurements using standardized surgical tables. To optimize outcomes, adjustable suture techniques are often incorporated, especially in adults or complex cases. The extraocular muscle is secured to the with a temporary or bow-tie suture, allowing postoperative repositioning. Once the patient recovers from (typically 2-4 hours post-surgery), eye alignment is assessed, and adjustments are made by sliding the suture under topical in a setting, usually within 24 hours to fine-tune alignment and minimize residual deviation. Transposition surgeries address paralytic strabismus, such as in or , where vertical rectus muscles (superior and/or inferior) are detached and reattached adjacent to the lateral rectus insertion to redirect their force and augment abduction, correcting 20-50 prism diopters of while preserving anterior ciliary circulation. In children, eye muscle surgery is recommended before age 7 to prevent , as untreated misalignment during the critical visual development period can lead to permanent vision loss in the deviating eye. Success rates for horizontal correction range from 70-80%, defined as alignment within 10 prism diopters of orthotropia at long-term follow-up, though reoperations may be needed in 20-30% of cases. Complications are uncommon but include overcorrection in approximately 10% of patients, often resolving spontaneously or requiring revision, and anterior segment ischemia—a rare vascular issue (incidence ~1 in 13,000)—which is more likely with surgeries involving three or more rectus muscles due to disruption of , presenting as corneal or hypotony within 24 hours.

Reconstructive and Ablative Procedures

Eye Removal and Prosthetics

Eye removal, also known as enucleation or evisceration, is a surgical intervention performed to address severe ocular conditions such as malignancies, in blind eyes, or extensive trauma, allowing for subsequent prosthetic rehabilitation to restore and psychological well-being. These procedures preserve orbital structures to facilitate and volume replacement, with enucleation involving complete globe excision and evisceration focusing on intraocular content removal while retaining the scleral shell. Postoperatively, orbital implants and custom prosthetics are integrated to mimic natural eye appearance and function, supporting patient adaptation through multidisciplinary care including psychological counseling. Enucleation entails the surgical removal of the entire ocular while preserving the to maintain orbital motility. The procedure begins with a 360-degree conjunctival peritomy at the limbus, followed by blunt dissection in the sub-Tenon's space to isolate the rectus and oblique muscles, which are then secured with sutures before being severed close to their insertions. The is isolated and sectioned approximately 5-10 mm behind the globe, ensuring throughout. This approach is particularly indicated for intraocular malignancies like , where histologic examination of the intact globe and is essential for staging and . Evisceration, in contrast, involves excising the intraocular contents through an incision in the or while preserving the corneoscleral shell and attached , which enhances prosthetic compared to enucleation. The surgical steps include a 360-degree conjunctival peritomy, evisceration of uveal tissue and vitreous via a scleral or limbal incision, thorough to remove residual intraocular material, and closure of the with nonabsorbable sutures. It is preferred for cases of or painful blind eyes without suspected malignancy, as it reduces operative time and infection risk while providing superior cosmetic outcomes due to better muscle-sclera attachment. Following removal, an orbital implant is placed in the intraconal space to restore volume and support prosthetic movement, typically wrapped in donor or synthetic material to prevent exposure. Common implants include , which promotes fibrovascular ingrowth for pegged prosthetic attachment, and porous , valued for its , lower cost, and direct muscle suturing capability without wrapping; sizes range from 18 to 22 mm in diameter, selected based on the patient's axial length minus 2 mm to achieve symmetry. These implants are secured by suturing the directly or to the wrapping, with the socket closed in layers using absorbable sutures. Prosthetic ocular fitting occurs 6-8 weeks postoperatively, once conjunctival is confirmed, involving the creation of a custom acrylic shell matched to the fellow eye's volume and iris via impression molding, painting, and polishing for natural appearance. may guide volume assessment for precise fitting, with the pegged to for enhanced if fibrovascularization is adequate. Regular follow-ups with an ocularist ensure , often spanning decades with proper , while psychological support addresses concerns integral to rehabilitation. Indications for these procedures include trauma, accounting for approximately 30-40% of cases in various studies, and tumors such as in children, comprising 16-28% of enucleations, alongside and painful blind eyes to alleviate suffering and prevent complications.

Keratoprosthesis and Artificial

Keratoprosthesis refers to artificial designed for patients with severe corneal blindness who are not candidates for traditional donor tissue transplants due to repeated graft failures or underlying conditions like autoimmune diseases. These devices aim to restore vision by replacing the opaque or damaged with a synthetic optical component, often integrated with biological skirts to promote stability and reduce rejection risks. Unlike standard corneal transplants, keratoprostheses bypass the need for viable donor but require meticulous postoperative care to manage complications such as and tissue melting. The Boston Keratoprosthesis (KPro) is the most commonly implanted artificial worldwide, with two primary variants tailored to specific indications. Type I KPro is indicated for eyes with multiple failed penetrating keratoplasties or corneal opacities where further donor grafts are unlikely to succeed, such as in cases of limbal deficiency. It consists of an optical polymethylmethacrylate (PMMA) cylinder embedded in a donor corneal skirt, secured between front and back plates for fixation. Type II KPro, reserved for more severe ocular surface disorders like chemical burns or Stevens-Johnson syndrome, features a longer stem that protrudes through a ( fusion) to protect the device from the external environment.00306-1/fulltext) Osteo-odonto-keratoprosthesis (OOKP) represents an autologous alternative for patients with end-stage dry eye or bilateral corneal blindness unsuitable for other procedures, utilizing the patient's own and adjacent to minimize rejection. In this two-stage , a canine or is harvested along with its alveolar (lamina) to form a biological skirt around a PMMA optic cylinder; the first stage involves subcutaneous implantation in the cheek for bio-integration, followed by the second stage where the construct is transplanted into the eye after trephination of the damaged . This approach is particularly beneficial for autoimmune conditions causing severe ocular surface damage, as the autologous tissue supports long-term stability without systemic . Implantation of both Boston KPro and OOKP typically begins with trephination—a precise circular excision of the host using a blade—to create a bed for the device. The prosthesis is then assembled: for Type I KPro, the donor skirt is sandwiched between plates and sutured or bolted into the recipient bed with 10-0 nylon sutures; Type II involves passing the stem through the eyelid before fixation. OOKP fixation relies on the bone-tooth lamina's natural integration, secured with periosteal flaps and sutures. Postoperatively, patients require lifelong topical , primarily cyclosporine 0.05% drops four times daily, combined with steroids to prevent sterile and , alongside bandage contact lenses to maintain hydration. Clinical outcomes for keratoprostheses demonstrate significant vision restoration, though tempered by complication rates. In KPro series, 50-70% of patients achieve and retain of 20/200 or better at 2-5 years postoperatively, with Type I showing higher retention rates than Type II due to better surface protection. For OOKP, anatomical success exceeds 90% at 10 years, with over 60% attaining functional vision (20/200 or better), attributed to the autologous design. The most prevalent complication across devices is retroprosthetic formation, affecting 50-60% of cases, which obscures the but is often managed with neodymium:yttrium-aluminum-garnet (YAG) laser membranectomy. Other risks include (20-40%), (5-15%), and device extrusion (10-20%), necessitating vigilant monitoring.30660-1/fulltext)00213-6/fulltext)00306-1/fulltext) As of 2025, advancements in bioengineered corneal scaffolds are emerging to complement traditional keratoprostheses by promoting partial tissue integration and reducing long-term complications. These scaffolds, often composed of or decellularized matrices seeded with limbal stem cells or induced pluripotent stem cell-derived corneal cells, facilitate endogenous regeneration in partial-thickness defects, potentially serving as hybrid alternatives for early-stage failures. Preclinical and early clinical trials report improved and vascularization, with reduced rejection rates compared to fully synthetic devices, though full adoption awaits larger studies.

References

Add your contribution
Related Hubs
User Avatar
No comments yet.