Table 1. Recommendation Grading
|I||High-quality meta-analyses, systematic reviews of randomized controlled trials (RCTs), or RCTs with a very low risk of bias|
|I||Well-conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias|
|I-||Meta-analyses, systematic reviews of RCTs, or RCTs with a high risk of bias|
|II||High-quality systematic reviews of case-control or cohort studies High-quality case-control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal|
|II||Well-conducted case-control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal|
|II-||Case-control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship is not causal|
|III||Nonanalytic studies (e.g., case reports, case series)|
|G - Good quality||Further research is very unlikely to change our confidence in the estimate of effect|
|M - Moderate quality||Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate|
|In - Insufficient quality||Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate Any estimate of effect is very uncertain|
|S - Strong recommendation||Used when the desirable effects of an intervention clearly outweigh the undesirable effects or clearly do not|
|D - Discretionary recommendation||Used when the trade-offs are less certain—either because of low-quality evidence or because evidence suggests that desirable and undesirable effects are closely balanced|
- To rate individual studies, a scale based on Scottish Intercollegiate Guideline Network (SIGN) is used.
- The body of evidence quality ratings is defined by Grading of Recommendations Assessment, Development and Evaluation (GRADE). GRADE is a systematic approach to grading the strength of the total body of evidence that is available to support recommendations on a specific clinical management issue.
- Key recommendations for care are defined by GRADE.
- Understanding the current disease definition is important in the management of primary angle closure (PAC). Modern classification includes:
- Primary angle-closure suspect (≥180° iridotrabecular contact (ITC), normal intraocular pressure [IOP], and no optic nerve damage)
- Primary angle closure (≥180° ITC with peripheral anterior synechiae [PAS] or elevated IOP, but no optic neuropathy)
- Primary angle-closure glaucoma (≥180° ITC with PAS, elevated IOP, and optic neuropathy)
- Acute angle-closure crisis (AACC; occluded angle with symptomatic high IOP)
- Plateau iris configuration (any ITC persisting after a patent laser peripheral iridotomy [LPI]) or syndrome (any ITC persisting after a patent LPI with pressure elevation after dilation)
(The management of other secondary forms of angle closure (e.g., iris bombé) is not discussed in this pocket card.)
- Common risk factors for PAC include Asian descent; hyperopia; older age; female gender; short axial length; and the size, shape, or position of the crystalline lens.
- The prevalence of angle closure varies from ≤0.6% in European and European-derived populations to 3.8% in one study of Alaskan Inuits.
- The clinical signs and symptoms of AACC include pressure-induced corneal edema (experienced as blurred vision and occasionally as multicolored haloes around lights), a mid-dilated pupil, vascular (i.e., conjunctival and episcleral) congestion, eye pain, headache, nausea, and/or vomiting.
- Dark-room dynamic gonioscopy (as described in the subsection Gonioscopy in the Diagnosis section) should be performed to diagnose angle-closure disease and to verify improvement in angle configuration following treatment.
- Patients experiencing AACC should receive aqueous suppressants to lower the IOP acutely and laser iridotomy or iridectomy. After addressing the episode of AACC, it is important to perform LPI in the fellow eye when indicated.
- The patient should be asked about symptoms that may suggest previous episodes of intermittent angle closure (e.g., blurred vision, haloes around lights, eye pain, headache, eye redness, symptoms following stress or dilated eye examination). (G, S)
- Specific questioning should address the use of oral medications that may cause ciliary body edema (e.g., sulfonamides, topiramate) and topical, inhaled, or oral drugs with adrenergic or anticholinergic effects (e.g., ipratropium bromide and salbutamol-containing inhalers, phenothiazines, or other drugs with anticholinergic activity) that may induce angle narrowing and potentially precipitate an angle-closure attack. (G, S)
- Hyperopic eyes, especially in older phakic patients, have narrower anterior chamber angles and are at increased risk of PAC. Assessment of actual refractive status by retinoscopy or manifest refraction in the AACC eye may be postponed until a subsequent visit. It is appropriate to determine the presence of hyperopia by measuring the eyeglass power or refracting the fellow eye.
- For patients with suspected occludable angles, pupil dilation should be done with caution. As appropriate, these patients should be warned about signs and symptoms until an iridotomy has been performed, since dilation can precipitate AACCs. (G, S)
- Size and shape (may be mid-dilated, asymmetric, or oval in the involved eye during or following an AACC)
- Reactivity (may be poor during an AACC or nonreactive following an AACC)
- Relative afferent pupillary defect (may be present with asymmetric optic nerve damage or be due to elevated IOP)
- Conjunctival hyperemia (in acute cases)
- Central and peripheral anterior chamber depth narrowing
- Anterior chamber inflammation suggestive of a recent or current attack
- Corneal swelling. (Microcystic edema and stromal edema are common in acute cases.)
- Iris abnormalities, including diffuse or focal atrophy, posterior synechiae, abnormal pupillary function, irregular pupil shape, and a mid-dilated pupil (suggestive of a recent or current attack)
- Lens changes, including cataract and glaukomflecken (patchy, localized, anterior subcapsular lens opacities) (see Figures 1 and 2)
- Corneal endothelial cell loss
- Gonioscopy of both eyes should be performed on all patients in whom angle closure is suspected to evaluate the angle anatomy, presence of ITC and/or PAS, and plateau iris configuration. Compression (indentation) gonioscopy with a four-mirror or similar lens is particularly helpful to determine if visible appositional closure is actually permanent synechial closure and, if so, the extent of such PAS.
- Dark-room gonioscopy and IOP measurements should be performed pre- and post-dilation to ensure a non-occludable angle following the LPI. (G, S)
Anterior Segment Imaging
- Anterior segment imaging should be considered when angle anatomy is difficult to assess on gonioscopy.
Table 2. Clinical Findings That Define Patients Seen With Angle-Closure Disease
|Primary Angle-Closure Suspect||Primary Angle Closure||Primary Angle-Closure Glaucoma|
|Elevated IOP or PAS||Absent||Present||Present|
|Optic nerve damage||Absent||Absent||Present|