560 likes | 694 Views
Preferred practice pattern. Dr . Fahad alzwaidi R2. Catract in adult. Systemic Comorbidities. diabetes mellitus, pulmonary dysfunction, cardiovascular dysfunction (e.g., poorly controlled blood pressure, heart failure),
E N D
Preferred practice pattern Dr . Fahadalzwaidi R2
Systemic Comorbidities • diabetes mellitus, • pulmonary dysfunction, • cardiovascular dysfunction (e.g., poorly controlled blood pressure, heart failure), • musculoskeletal disorders causing positional difficulties, tremor, hearing impairment, anxiety , mental retardation, dementia, and coagulopathies .
IFIS • systemic alpha-1 antagonists . • avoid the initiation of alpha-1 antagonists until their cataract surgery is completed . • Discontinuing does not typically prevent IFIS, which may occur long after drug cessation. • severe in patients taking the alpha-1A subtype specific antagonist, tamsulosin .
Discontinuation of anticoagulant , antiplatelet • Several uncontrolled case series reported minimal or no complications in patients who were maintained on (alternatives to retrobulbar ) • associated with medical morbidity. (In patients with new coronary stents , stent thrombosis )
systemic antibiotic No recommendations from AHA , AAOO to prescribe systemic antibiotic prophylaxis for patients with artificial heart valves or joint prostheses who are undergoing cataract surgery.
HIGH-RISK CHARACTERISTICS Deeply set eye : visibility , access to the limbus ,Pooling of irrigation fluid wound deformation and leakage . Dense brunescent nuclear cataract : zonular laxity and miosis , Little cortex to protect the capsule , phacoemulsification time .
High hyperopia : endothelial trauma , iris trauma and prolapse , calculating lens power , suprachoroidal effusion (particularly in nanophthalmic eyes) . High myopia : depth fluctuation due to reverse pupillary block , calculating power , decreased ocular rigidity , difficult sealing the wound , risk of retinal detachment .
Miotic pupil : capsule tear/vitreous prolapse, iris damage and prolapse Prior scleral buckling surgery : Change in axial length ,Conjunctival scarring Increased risk of sclera perforation with injection anesthesia .
Cataract Surgery and Glaucoma options include : ……………………. Glaucoma surgical options : trabeculectomy , drainage devices, and endocyclophotocoagulation
Benefits are protection against a potential postoperative IOP spike and long-term IOP control with a single operation. • potentially indicated in eyes with active uveitis, neovascularization, or multiple anterior segment problems . • Glaucoma surgery prior : anesthetic risks , inducing filtration failure as a result of subsequent cataract surgery.
Cataract surgery with IOL implantation alone • suspected or confirmed primary angle closure . • mild to moderately severe open-angle glaucoma controlled on medication. • modest reduction of IOP .
Studies have found that the degree of IOP reduction is greater with higher preoperative IOP levels and that the benefit may last for several years.
In general • Phacoemulsification combined with trabeculectomy provides good IOP control . But its not as effective as glaucoma surgery alone . • Both one-site and two-site combined procedures appear to provide similar IOP reduction .
New glaucoma technologies like : Canaloplasty , abinternotrabeculotomy , and abinternotrabecular bypass microstents may reduce the risk of hypotony and bleb complications, but they may not lower the IOP as much.
uses of antifibrotic agents (mitomycin-C and 5-fluorouracil) to reduce the potential for bleb failure remains controversial. • mitomycin-C may be effective in producing lower long-term IOPs , 5-fluorouracil is not .
Cataract Surgery and Keratoplasty • Evaluation of the corneal endothelium . microcystic edema or stromal thickening, central corneal pachymetry greater than 640 microns and/or low central endothelial cell counts by specular microscopy . History : prolonged "foggy vision" upon awakening in the morning .
reasons to consider combining cataract extraction with corneal transplantation . • Cataracts may progress more rapidly after corneal transplantation . • corticosteroids following surgery may hasten PSC cataract development . • Cataract surgery subsequent to corneal transplantation may damage the corneal graft . • Visual rehabilitation is more rapid .
With borderline endothelial reserve : A more peripheral incision, either temporal clear cornea or corneoscleral, and repeated instillation of OVD may preserve more endothelial cells .
some surgeons prefer to perform penetrating keratoplasty first, followed by cataract removal later after the corneal graft has stabilized . • this approach reducing the amount of time the eye is open during the penetrating keratoplasty surgery.
An alternative procedure : transplantation of the endothelium and posterior stroma or replacement of the endothelial layer with Descemet's membrane alone. • Can combined with phacoemulsification and foldable IOL implantation. • preserves the anterior corneal curvature .
Descemet's stripping endothelial keratoplasty : ( change posterior corneal contour) • Induce a hyperopic refractive shift . (+0.6 D after 12 months in one study,+1.47 D ) • should be considered if there is significant risk of corneal decompensation following cataract surgery.
If the indication for considering corneal transplantation is the presence of a central opacity : performing cataract surgery followed by a sphincterotomy, establishing a clear entrance pupil.
Cataract Surgery and Uveitis • postoperative problems : adhesions between the iris and lens capsule , membrane formation, IOL deposits, zonular problems, and CME.
specialissues When patients with uveitis undergo cataract surgery • Inactive or at its best level of control . • Even if the patient is on chronic anti-inflammatory therapy, additional topical or oral corticosteroids . • In one study pre op oral sreroid : > decrease the risk of postoperative CME.
medical regimen should be individualized . (the severity and sequelae of past episodes ) • Surgical planning should take into account the possible need for other procedures . • Prcedure modify bec. pre-existing posterior synechiae, pupillary membranes, and fibrotic scarring of the pupillary margin.
lens material does not seem to be a major influence on the course of postoperative inflammation. • IOL haptics into the capsular bag is preferred. ( large diameter capsulorhexis ) • Aphakic . Complications • inflammatory deposits, • surface membrane formation, and • inflammatory capsular complications capable of causing IOL subluxation .
excessive iris manipulation should be avoided . • Postoperative use of topical mydriatic agents . ( short-acting ) • Adjunctive corticosteroids at the time of surgery(intravenous, periocular, or intraocular) Postoperatively • frequency and duration of corticosteroid . • should be monitored closely .
Cataract Surgery and Vitreoretinal Surgery • it is often necessary . • Vitreoretinal procedures may cause pre-existing cataracts to progress . so Management of such cataracts may be more complex, because capsular defects or weakened zonules may be present.
A wide range of vitreoretinal disorders may be dealt with concomitantly including : vitreous hemorrhage, diabetic retinopathy, epiretinal membrane, macular hole, and retinal detachment. • in-the-bag placement of a foldable IOL is a good option . • Myopic shift .
complex cases : • pars plana lens fragmentation with simultaneous or later sulcus placement of a posterior chamber IOL . • Secure wound closure is important to permit safe vitreoretinal maneuvers . • nature of the posterior segment pathology for visualization ( ie . silicone optic )
Disadvantages : • prolonged surgical time, • cataract-wound dehiscence during subsequent vitreoretinal surgery, • Intraoperativemiosis after cataract extraction, • IOL decentration or optic capture .
Cataract Surgery Following Refractive Surgery • challenges : in addtion to IOL calculation . IOL formulas predict the effective lens position based on the corneal steepness this will introduces a formula artifact.
Following radial keratotomy : • Need to avoid the new incision cross pre-existing incisions . ( leak, delayed healing, and irregular astigmatism) • Induced central corneal flattening automated computerized videokeratography (topography or tomography) .
Following excimer laser refractive surgery : all corneal power readings incorrect as result • surgical alteration of the anterior corneal curvature and , • the changed relationship between anterior and posterior corneal powers. myopic photoablation ---- hyperopic refractive errors So , beneficial to utilize the Aramberri Double-K method to refine IOL power determination .
Cataract in the Functionally Monocular Patient • indications for surgery same as for other patients . • delaying surgery until the cataract is very advanced may increase surgical risk and slow visual recovery .
Second-Eye Surgery • Clinical studies have providedthat binocular summation occurs in similar visual acuities in the two eyes and at low illuminance levels. • with dissimilar acuitiesin the two eyes may exhibit binocular inhibition. • that stereoacuity increased from 32% to 90% after second-eye surgery.
Determining the appropriate interval : • the patient's visual needs and preferences, • visual acuity and function of the second eye, • the medical and refractive stability of the first eye, and • degree of anisometropia .
Immediate Sequential (Same Day) Bilateral Cataract Surgery • need for general anesthesia . • when the health of the patient may limit surgery to one surgical encounter. • rare occasions where travel for surgery is hardship for pt .
Discharge from Surgical Facility Criteria : • Vital signs are stable . • Preoperative mental state is restored . • Nausea and vomiting are controlled . • Pain is absent or minimal . • Postsurgical care has been reviewed follow up .
hospitalization include • hyphema, uncontrolled • elevated IOP, • threatened or actual expulsive suprachoroidal hemorrhage, • retrobulbar hemorrhage, • severe pain,
Postoperative Management follow up • The ophthalmologist has an obligation to inform patients about signs and symptoms of possible complications, eye protection, activities, medications, required visits, and details for access to emergency care. • In the absence of complications, postoperative visits depend largely on the size of incision R/O suture , refraction .
Interval history, including use of postoperative medications, new symptoms, and self-assessment of vision . • Visual acuity, including P.H testing or refraction . • Measurement of IOP • SLE • Counseling/education for the patient or patient's caretaker .
fundus examination if there is a reasonable suspicion or higher risk of posterior segment problems. • visual improvement is less than anticipated : diagnostic test ie. if maculopathy is suspected, OCT or fluorescein angiography . • Optical correction : 1 and 4 wks small-incision 12 wks large-incision .
Posterior Capsular Opacification • evidence supports a lower PCO rate when the anterior capsulorrhexis completely overlaps the entire optic. • Polishing of the anterior capsule has a variable effect on reducing PCO rates . But it do in --- anterior capsule fibrosis and contracture reduce this phenomena .