Intracameral anesthesia: a report by the American Academy of Ophthalmology

OBJECTIVE: This document describes the technique of intracameral anesthesia and examines the available evidence to address questions about its effectiveness, possible corneal endothelial and retinal toxicity, and the optimal and maximal dose. METHODS: A literature search conducted for the years 1968 to 2000 retrieved over 180 citations that matched the search criteria. Panel members and a methodologist reviewed this information, and it was evaluated for the quality of the evidence presented. RESULTS: Some studies report effectiveness of intracameral anesthesia while others report no effect. In those studies showing an effect, levels of pain in the groups that were compared were low. Short-term studies seem to indicate that preservative (methylparaben)-free lidocaine 1% is well tolerated by the corneal endothelium but that higher concentrations of lidocaine are toxic. There is some evidence of electroretinogram changes after exposure to lidocaine or bupivacaine. CONCLUSIONS: The ideal timing and placement of intracameral anesthesia has not been determined. Because topical anesthesia alone is effective, surgeons may elect to use intracameral anesthesia for incremental pain control in patients who cannot be adequately managed with topical alone. Appropriate patient selection is important when using this method of anesthesia. While short-term studies seem to indicate safety, long-term effects are unknown. Patient preferences for anesthesia are not well studied.     

Cyclophotocoagulation: a report by the American Academy of Ophthalmology.

OBJECTIVE: This document describes cyclophotocoagulation procedures for glaucoma and examines the evidence to answer key questions about patient selection, and efficacy of transscleral and endoscopic techniques. METHODS: A literature search conducted for the years 1968 to 2000 retrieved 130 citations. The author reviewed 34 of these articles and selected 19 for the panel methodologist to review and rate according to the strength of evidence. A Level I rating is assigned to properly conducted, well-designed, randomized clinical trials; a Level II rating is assigned to well-designed cohort and case-control studies; and a Level III rating is assigned to case series and poorly designed prospective and retrospective studies, including case-control studies. RESULTS: The predominant problem with all studies on cyclophotocoagulation is the lack of a uniform definition of success, which makes comparisons difficult. One randomized controlled trial (Level I evidence) compared the efficacy of transscleral cyclophotocoagulation with noncontact Nd:YAG and semiconductor diode laser. It found no significant difference between the two, although a significant problem was the variability allowed with laser parameters. Most of the literature consists of noncomparative case series that provide evidence that is limited and often not convincing. CONCLUSION: Cyclophotocoagulation is indicated for patients with refractory glaucoma who have failed trabeculectomy or tube shunt procedures, patients with minimal useful vision and elevated intraocular pressure, and patients who have no visual potential and need pain relief (based on Level III evidence). It may be useful for patients whose general medical condition precludes invasive surgery or who refuse more aggressive surgery (i.e., filter or tube). It is also useful in emergent situations, such as the acute onset of neovascular glaucoma. There is insufficient evidence to definitively compare the relative efficacy of the cyclophotocoagulation procedures for glaucoma. It is the panel's opinion, however, that semiconductor diode systems appear to possess the best combination of effectiveness (based on Level III evidence), portability, expense, and ease of use at this time.     

Confocal microscopy: a report by the American Academy of Ophthalmology

OBJECTIVE: To review the available evidence for the use of confocal microscopy in diagnosing infectious keratitis and for other applications for ophthalmic practice. METHODS: A MEDLINE search of the peer-reviewed literature for the years 1990 to 2001 yielded 94 citations. The search was limited to studies of human subjects published in English with abstracts. The Ophthalmic Technology Assessment Committee Cornea Panel evaluated these 94 articles for possible clinical relevance and selected 51 (54%) for content review by the panel members. Of these 51 articles, 24 were selected for the panel methodologist to review and rate according to the strength of evidence. RESULTS: Of the 24 articles, 21 (87.5%) were classified as case reports or case series and were rated as level III evidence. Three articles were classified as independent, masked, or objective comparisons performed in a narrow spectrum of patients or in a nonconsecutive series of patients and were rated as level II evidence. No studies were rated as level I evidence, defined as an independent masked comparison of an appropriate spectrum of consecutive patients. CONCLUSION: Confocal microscopy is a new technology with clinical applications in ophthalmology. Although confocal microscopy has been used in other fields of medicine, the optical transparency of the cornea and other structures of the eye provides a unique opportunity to apply this technology. The targeted literature review of 24 articles found no level I studies to support the use of confocal microscopy in the management of eye disorders. Three level II studies pertained to promising clinical applications of the confocal microscope and provided evidence that supports the use of confocal microscopy as an adjunctive modality for diagnosing Acanthamoeba keratitis. The remaining 21 articles, rated as level III evidence, focus on the use of confocal microscopy to facilitate the diagnosis of infectious keratitis, including amoebic and fungal, but currently there are no definitive studies of its role in the differential diagnosis of this condition. There are also level III studies that support the use of the confocal microscope in refractive surgery. Facilitating the diagnosis of infectious keratitis and applying the confocal microscope to refractive surgery may hold the greatest promise of this new technology.     

Endonasal dacryocystorhinostomy: a report by the American Academy of Ophthalmology.

OBJECTIVE: This document describes endonasal dacryocystorhinostomy (DCR) and examines the evidence to answer key questions about the effectiveness of the procedure compared with external DCR; the relative indications, contraindications, advantages, and limitations of the procedure; and patient selection, surgical technique, postoperative care, and complications. METHODS: A literature search conducted for the years 1968 to 2000 retrieved 93 citations. The panel members reviewed 71 of these articles and selected 64 for the panel methodologist to review and rate according to the strength of evidence. A level I rating is assigned to properly conducted, well-designed, randomized clinical trials; a level II rating is assigned to well-designed cohort and case-control studies; and a level III rating is assigned to case series and poorly designed prospective and retrospective studies, including case-control studies. RESULTS: The published literature includes two reports that describe clinical trials comparing endonasal with external DCR with a 1-year follow-up. The success rate was 91% for the external DCR group in both reports and 63% and 75% for the endonasal DCR groups, defined by patency to irrigation. A longitudinal cohort study included a control group of age-matched external DCR patients who were compared with a study group of endonasal DCR patients. The reported success rate at 9 months following surgery for the endonasal cohort was 90% and was not statistically significantly different from the 94% success rate noted in the external DCR control group. Remaining data on reported success rates of primary and revision endonasal DCR were obtained from a collection of uncontrolled observational case studies with varying periods of follow-up and success rates ranging from 59% to 100%. CONCLUSIONS: It is difficult to make definite evidence-based determinations about the relative efficacy of endonasal and external DCR because of the deficiencies in the reported literature. Based on level III evidence, the available data suggest that endonasal DCR may be a viable option for the correction of acquired nasolacrimal duct obstruction and complex forms of congenital dacryostenosis in selected patients. This procedure may be indicated on a primary basis or as revisional surgery following failed external or endonasal DCR. Some studies comparing endonasal DCR with external DCR suggested lower success rates in the endonasal group; other studies yielded success rates comparable with or exceeding those of external surgery. Reported complications of endonasal DCR do not generally appear to be greater in frequency or magnitude than those associated with external DCR. Disadvantages of endonasal DCR include the preferred use of general anesthesia by many surgeons, the high cost of expensive equipment and instrumentation, and the relatively steep learning curve for this procedure. Depending on the preference of the surgeon, more postoperative care may be required for patients undergoing endonasal DCR than external DCR. Both the advantages and the limitations of endonasal DCR relative to external DCR should be carefully discussed with patients who are contemplating endonasal surgery.     

Strabismus surgery for adults: a report by the American Academy of Ophthalmology

OBJECTIVE: To describe the effectiveness and safety of surgical treatment of adult patients with strabismus, and to review the reported functional benefits and complications of strabismus surgery for adults. METHODS: A literature search was conducted in September 2001. It was repeated and updated in April 2003, with retrieval of relevant citations. Panel members reviewed the articles and rated them according to their relevance to the topic and methodology. RESULTS: The literature search identified 49 reports that describe the surgical treatment of strabismus in adult patients and meet predetermined review criteria. Of these reports, 2 were of randomized controlled trials, and 1 addressed the primary objective of this review. In this randomized study of adults with strabismus, direct comparison of surgical correction with botulinum toxin A chemodenervation indicated that surgical treatment was superior to botulinum toxin A in realigning the eyes (76.9% vs. 29.4%, P = 0.027). Several large case series of adults with strabismus (level III evidence) with successful surgical realignment rates of 68% to 85% have been reported. Functional benefits of surgical treatment are reported in many patients. These include elimination of diplopia, development of binocular fusion, expansion of binocular visual fields, and improvement of head position. Surgical complications, including new, postoperative diplopia (1%-14%) or scleral perforation (0.8%-1.8%), occur in a minority of patients. Unplanned reoperations (subsequent strabismus procedures that were not anticipated as part of a staged treatment) were needed in up to 21% of patients in large case series of comitant strabismus, and in up to 50% of patients with thyroid ophthalmopathy. CONCLUSIONS: Despite the paucity of level I evidence from randomized controlled trials, the existing literature suggests that surgical treatment of adults with strabismus is safe and effective in improving ocular alignment. In many cases it improves visual function, based largely on level III evidence. Risks include unplanned reoperation, postoperative diplopia, and scleral perforation. Additional level I studies of surgical treatment of adult patients would help to document the effectiveness and substantiate the safety of this treatment.     

Orbital implants in enucleation surgery: a report by the American Academy of Ophthalmology

OBJECTIVE: To compare prosthetic and implant motility and the incidence of complications associated with porous and nonporous enucleation implants. METHODS: Literature searches conducted in January 2002 for 1985 to 2001 and May 2002 for October 2001 to 2002 retrieved relevant citations. The searches were conducted in MEDLINE and limited to articles published in English with abstracts. Panel members reviewed the articles for relevance to the assessment questions, and those considered relevant were rated according to the strength of the evidence. RESULTS: A randomized clinical trial and a longitudinal cohort study detected no difference in implant or prosthetic movement between nonpegged hydroxyapatite porous and spherical alloplastic nonporous implants. No controlled studies were retrieved that investigated whether pegging porous implants improves prosthetic movement. Several case series indicate that patients with pegged hydroxyapatite implants have some degree of improved prosthetic motility. Longitudinal cohort studies show that sclera-covered hydroxyapatite implants have higher exposure rates than sclera-covered silicone implants, and unwrapped porous polyethylene implants have higher exposure rates than unwrapped acrylic implants. There are numerous case series that document a wide range of implant exposure rates in patients with various enucleation implants. It is difficult to compare complication rates among implant types because patient populations vary, surgical techniques differ, and follow-up periods are often limited. CONCLUSIONS: Based on one randomized clinical trial, spherical alloplastic nonporous and nonpegged porous enucleation implants provide similar implant and prosthetic motility when they are implanted using similar surgical techniques. Coupling the prosthesis to a porous implant with a motility peg or post appears to improve prosthetic motility, but there are few available data in the literature that document the degree of the improvement. There is a widely variable incidence of porous implant exposure, but certain surgical techniques and the type of wrapping material seem to reduce the exposure rate. Additional research is needed to document the long-term incidence of complications related to porous enucleation implants and associated surgical techniques. This includes the use of wrapping materials and what procedural modifications, both surgical and prosthetic, are most effective in reducing these complications.     

Surgical management of macular holes: a report by the American Academy of Ophthalmology.

OBJECTIVE: The document describes macular hole surgery and examines the available evidence to address questions about the efficacy of the procedure for different stages of macular hole, complications during and after surgery, and modifications to the technique. METHODS: A literature search conducted for the years 1968 to 2000 retrieved over 400 citations that matched the search criteria. This information was reviewed by panel members and a methodologist, and it was evaluated for the quality of the evidence presented. RESULTS: There are three multicenter, controlled, randomized trials that constitute Level I evidence and compare the value of surgery versus observation for macular hole. There are three multicenter, controlled, randomized trials studying the use of adjuvant therapy in macular hole repair. Postoperative vision of 20/40 or better has been reported in 22% to 49% of patients in randomized trials. The risks of surgical complications include retinal detachment (3%), endophthalmitis (<1%), cataract (>75%), and late reopening the hole (2% to 10%). CONCLUSIONS: The evidence does not support surgery for patients with stage 1 holes. Level I evidence supports surgery for stage 2 holes to prevent progression to later stages of the disease and further visual loss. Level I evidence shows that surgery improves the vision in a majority of patients with stage 3 and stage 4 holes. There is no strong evidence that adjuvant therapy used at the time of surgery results in improved surgical outcomes. Patient inconvenience, patient preference, and quality of life issues have not been studied.     

Single-field fundus photography for diabetic retinopathy screening: a report by the American Academy of Ophthalmology

OBJECTIVE: To evaluate whether single-field fundus photography can be used as a screening tool to identify diabetic retinopathy for referral for further ophthalmic care. METHODS: A MEDLINE search of the peer-reviewed literature was conducted in June 2001 for the years 1968 to 2001 and updated in September 2003, yielding 145 articles. The search was limited to articles published in English. The Cochrane Library of clinical trials was also investigated. The authors reviewed the abstracts of these articles and selected 63 of possible clinical relevance for review by the panel. Of these 63 articles, the panel selected 32 for the panel methodologist to review and rate according to the strength of evidence. RESULTS: Three of the 32 articles reviewed were classified as level I evidence, and 4 were classified as level II evidence. Evidence from level I studies demonstrates that as a tool to detect vision-threatening retinopathy, single-field fundus photography interpreted by trained readers has sensitivity ranging from 61% to 90% and specificity ranging from 85% to 97% when compared with the gold standard reference of stereophotographs of 7 standard fields. When compared with dilated ophthalmoscopy by an ophthalmologist, single-field fundus photography has sensitivity ranging from 38% to 100% and specificity ranging from 75% to 100%. CONCLUSIONS: Single-field fundus photography is not a substitute for a comprehensive ophthalmic examination, but there is level I evidence that it can serve as a screening tool for diabetic retinopathy to identify patients with retinopathy for referral for ophthalmic evaluation and management. The advantages of single-field fundus photography interpreted by trained readers are ease of use (only one photograph is required), convenience, and ability to detect retinopathy. Further studies will be required to assess the implementation of single-field photography-based programs to confirm the clinical and cost-effectiveness of these techniques in improving population visual outcomes. Future research also should include establishing standardized protocols and satisfactory performance standards for diabetic retinopathy screening programs.     

Intrastromal corneal ring segments for low myopia: a report by the American Academy of Ophthalmology

OBJECTIVE: This document describes intrastromal corneal ring segments (Intacs) inserts technology and examines the evidence to answer the key question about whether the treatment is safe and effective in correcting low myopia. METHODS: A literature search that was conducted in September 2000 retrieved 13 relevant citations, and the reference lists of these articles were consulted for additional citations. Panel members reviewed this information and articles were rated according to the strength of evidence. RESULTS: Prospective multicenter phase II and III clinical trials (Level II evidence rating) of Intacs inserts for myopia of -1.00 to -3.00 diopters (D), with a maximum of +1.00 D of astigmatism, enrolled a total of 452 subjects, with a total of 454 surgical attempts. The results from phase II and phase III were pooled for much of the analysis. At 1 year, 97% of patients who completed follow-up had 20/40 or better uncorrected visual acuity (UCVA). Seventy-four percent of patients had 20/20 or better UCVA. Ninety-two percent of eyes were within +/-1 D of intended refractive correction, and 69% were within 0.5 D of intended refractive correction. At 3 months, 90% of patients had less than 1.0 D of change from the previous examination performed at 1 month. The ocular complication rate, which was defined as clinically significant events but not resulting in permanent sequelae, was 11% at 12 months. The adverse event rate was 1.1%, defined as a serious event if untreated. Nearly 9% of patients requested to have their inserts removed and a total of 3.8% of patients required a secondary surgical intervention. CONCLUSIONS: To date, evidence suggests that low myopia (-1 to -3 D) in a well-defined group of patients who have a stable manifest refraction and less than +1.0 D of astigmatism can be treated with Intacs inserts with a reasonable assurance of safety and effectiveness. Additional clinical research is needed to determine the long-term effectiveness of treatment and the comparative safety, effectiveness, and costs with other treatment modalities, including laser-assisted in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).     

Intraocular lens implantation in the absence of capsular support: a report by the American Academy of Ophthalmology

OBJECTIVE: This review was conducted to determine the safety and efficacy of open-loop anterior chamber, scleral-sutured posterior chamber, and iris-sutured posterior chamber intraocular lenses (IOLs) in eyes with inadequate capsular support for posterior chamber implantation in the capsular bag or ciliary sulcus. It also attempted to determine whether there is a preferred IOL or fixation site of choice in eyes with inadequate capsular support. METHODS: A literature search conducted for the years 1980 to 2001 yielded 189 citations related to IOL implantation in the absence of capsular support. An update search, conducted in March 2002, yielded an additional 28 articles. The Anterior Segment Panel members reviewed these abstracts and selected 148 articles of possible clinical relevance for review. Of these, 89 were considered sufficiently clinically relevant for the panel methodologist to review and rate according to the strength of evidence. A level I rating was assigned to properly conducted, well-designed, randomized clinical trials; a level II rating was assigned to well-designed cohort and case-control studies; and a level III rating was assigned to case series. Articles comparing the safety and efficacy of the IOL type and fixation site were further evaluated for the quality of the statistical methods used in the study. Studies with a rating of A or B were considered acceptable, C was borderline, and D and F were considered unacceptable as medical evidence. RESULTS: Forty-three articles with data concerning outcome of IOL insertion in eyes with inadequate capsular support had an evidence rating of level III or higher and were used in the final review of the safety and efficacy of one or more lens types and/or fixation sites. Seven articles had data about more than one lens type. Six had a statistical method rating of C or higher and were used to evaluate differences in visual outcomes and complication rates between lens types and fixation sites. CONCLUSIONS: The literature supports the safe and effective use of open-loop anterior chamber, scleral-sutured posterior chamber, and iris-sutured posterior chamber IOLs for the correction of aphakia in eyes without adequate capsular support for placement of a posterior chamber lens in the capsular bag or ciliary sulcus. At this time, there is insufficient evidence to demonstrate the superiority of one lens type or fixation site. Precise determination of small differences in visual outcome or complication rates will require a large prospective, randomized clinical trial.